Technical Field
[0001] The invention relates to a method for crimping a crimp element to a conductor, a
crimp device configured to perform that method, a respective control unit and machine-readable
program code.
[0002] The present invention is mainly described in connection with data cables. It is understood
that the present invention can be used for any type of cable.
State of the art
[0003] When manufacturing data cables, the cables are usually processed in an automated
processing plant and, for example, assembled, i.e., cut to the appropriate length
and provided with appropriate electrical contacts and/or connectors.
[0004] The invention relates specifically to crimp devices and a respective crimping process,
especially for such cables. During such a crimping process a crimp element, typically
a crimp barrel or a crimp sleeve, which can have a variety of embodiments, is connected
to a conductor of a cable, especially to strands, by crimping.
[0005] Crimping is as process of joining two pieces of metal or other materials by cold
deformation of one or both of these pieces to create a mechanical connection between
them. Crimping is realized by using a crimp device comprising a crimping tool and
a crimp anvil. The two pieces to be connected are pressed or squeeze together between
the crimping tool and the crimp anvil to create a secure mechanical connection. In
case of cables often crimping is not only used to establish a mechanical connection
but also an electrical connection between the two pieces.
[0006] To control the crimping process in a better way typically crimping dies are used
by the crimping tool and/or the crimp anvil, which shall provide defined conditions
during the actual crimping process. The crimping dies may provide a specific shape
or pattern in the material, such as a series of ridges or grooves, which helps to
lock the pieces together and prevent them from separating.
[0007] Crimping is commonly used in a wide range of applications, especially in electrical
wiring. In electrical wiring, for example, crimping is used to attach connectors to
wires, creating a secure and reliable connection.
[0008] To maintain a continuous quality for the crimping process the crimping process needs
to be controlled. In the past this was often realized by an offline manual monitoring
of the crimping process by analysing the manufactured crimped connection. Especially
grinding images have been used to acquire knowledge if a crimped connection satisfies
the desired quality requirements.
[0009] In addition, crimping parameter are regularly checked, e.g. like crimping height,
are regularly checked during the manufacturing process, especially when the crimping
conditions were changed in a controlled manner, e.g. from the processing of a first
set of crimp elements to a second set of crimp elements or the crimping dies have
been exchanged.
[0010] However, such manual monitoring of the crimping process is burdensome and the reaction
time from defectively manufactured crimped connections to actively improve the manufacturing
process is high.
[0011] Attempts have been made to improve such monitoring of the crimping process e.g. by
applying automatic crimp force monitoring comparing detected time-based crimp force
signals with a reference signal curve for time-based crimp force signals. Further
attempts utilize e.g. image based analysis methods.
[0012] Such image-based analysis method for manufactured crimped connections is e.g. known
from
DE 102019107687 A1 disclosing a method for ensuring and/or checking the quality of a crimping using
a crimping machine for crimping a cable with a contact sleeve and using a first optical
sensor for detecting and/or recording first image data of the contact sleeve and using
an evaluation electronics system, comprising the following steps: the first image
data of the contact sleeve are detected by the first optical sensor; the evaluation
electronics system carries out a first comparison of the first image data of the first
optical sensor with first reference data of a predetermined contact sleeve, and the
first comparison is checked for the presence of a predetermined first criterion; if
the predetermined first criterion is satisfied, a first signal is output; wherein
the detection of the first image data and the first comparison and the checking of
the first criterion and the output of the first signal are carried out before the
cable is crimped with the contact sleeve.
[0013] Firstly, image processing programs based on classic rule-based object recognition
are often inflexible and complex, and in some cases very difficult to implement reliably.
[0014] Secondly, in manufacturing environments creating a significant amount of dust and
dirt, image-based solutions lead to challenges in terms of maintaining reliable image
acquisition conditions to enable a reliable analysis of crimp results.
Description of the invention
[0015] It is the object of the invention to provide a solution for a reliable, efficient,
and robust assessment of a crimping process, especially of a crimping result, during
the operation of a crimp device, especially in real-time.
[0016] The object is solved by the features of the independent claims. Advantageous further
embodiments of the invention are indicated in the dependent claims, the description,
and the accompanying figures. In particular, the independent claims of one claim category
may also be further developed analogously to the dependent claims of another claim
category. Further embodiments and further embodiments are provided by the independent
claims as well as by the description with reference to the figures.
[0017] The present invention relates especially to a method for crimping a crimp element
to a conductor by a crimp device comprising a crimping tool and a crimp anvil, whereas
at least one time-based signal is detected relating to a crimping process performed
by the crimp device, whereas the at least one time-based signal is analysed by applying
the at least one time-based signal to a trained neural network, whereas the trained
neural network is configured to classify a result of a crimping process based on the
received at least one time-based signal, whereas a classification result comprising
at least a class corresponding to a non-defective crimp result and a class corresponding
to a defective crimp result is determined, especially by the trained neural network,
based on the classification performed by the trained neural network, whereas a control
signal is generated and provided as output based on the determined classification
result.
[0018] This method provides a robust and reliable way to assess a result of a crimping process.
Especially, this method can be utilized for real-time monitoring of the crimping process.
The method is especially robust, as an image-based monitoring and/or analysis can
be avoided.
[0019] The crimping tool can comprise a crimping tool front end. The crimping tool front
end can be partly modified by exchangeable crimping dies adapted to a special crimping
task or special crimp element. Further the crimping tool may comprise a crimp press,
which presses the crimping tool front end on the crimp element, which is typically
arranged on a crimp anvil during the crimping process. Further a conductor is present,
which shall be connected to the crimp element by crimping. The conductor is typically
part of cable. The cable, the crimp element, as well as the conductor may have different
configurations.
[0020] The crimping tool front end and the crimp anvil may interact such that by pressing
the crimping tool front end to the crimp anvil, a crimp element and the conductor
positioned between the crimping tool and the crimp anvil are connected by cold deformation
of the crimp element. This deformation is suitable to connect the crimp element to
the conductor mechanically, but also electrically.
[0021] Crimp elements are the elements that shall be attached to a certain structure, e.g.
a conductor, by crimping. Crimp elements may especially comprise crimp barrels or
crimp sleeves. There is a high variety of different crimp elements e.g. dependent
on the configuration of the conductor they shall be attached to, on the configuration
of the cable and its purpose and on the manufacturing process following the crimping
process.
[0022] According to the method at least one time-based signal is detected relating to the
crimping process. The crimping process comprises especially the time period in which
a crimp element is crimped by the crimp device. As a 'time-based signal', a temporal
course of a signal shall be understood.
[0023] In context of the invention the signal is a detected signal for a defined period
of time by a specific detecting unit, typically a sensor enabled to detect time-based
signal, i.e. a temporal course of a signal.
[0024] The method is suitable to be performed with more than one time-based signal, especially
with time-based signals detected by different sensors, wherein the sensors may be
of the same or of different type. Time-based signals may be of different type. Respectively,
the sensors for time-based signals of different type are considered to be of different
type. This means time-based signals of different types correspond typically to different
physical variables. This applies correspondingly to the different types of sensors.
E.g. a time-based position signal is a different signal type compared to a time-based
force signal or compared to a structure-borne sound signal. For detecting such different
types of time-based signals, typically different types of sensors are used.
[0025] By considering a plurality of time-based signals, especially of different types,
the accuracy of the assessment of the crimping result can be increased.
[0026] It has shown that one time-based signal is already sufficient to determine a sufficiently
reliable classification result for connection of the crimp element and the conductor
based on the time-based signal captured during its production. Such classification
result provides at least the information, if a result of a crimping process is assessed
to be defective or non-defective.
[0027] As such at least one time-based signal generated by a specific crimping process,
which especially comprises the contact phase of the crimping tool and the crimp element,
is closely related to the underlying crimping process, such time-based signal is a
suitable basis for determining a classification result of a crimping process generating
such at least one time-based signal.
[0028] It has shown that such at least one time-based signal related to the crimping process
can be used to assess the crimping result derived by the crimping process to which
the time-based signal is related.
[0029] This is achieved by applying the at least one time-based signal to a trained neural
network, whereas the trained neural network is configured to classify a result of
a crimping process based on the received at least one time-based signal, whereas a
classification result comprising at least a class corresponding to a non-defective
crimp result and a class corresponding to a defective crimp result is determined,
especially by the trained neural network, based on the classification performed by
the trained neural network, whereas a control signal is generated and provided as
output based on the determined classification result.
[0030] Conventional signal analysis of at least one time-based signal of the crimping process
is not successful in relating an assessment of a crimp result to the at least one
conventionally analysed time-based signal. Therefore, the invention envisages to make
use of a respectively trained neural network, especially a deep neural network (Deep
Neural Network, DNN), especially a deep recurrent neural network (Deep Recurrent Neural
Network, DRNN) or a deep convolutional neural network (Deep Convolutional Neural Network,
DCNN), which is applied to the at least one time-based structure-borne sound signal
or to the at least one time-based force signal, respectively.
[0031] The trained neural network is configured to classify a result of the crimping process,
especially a crimped connection, on basis of the provided at least one time-based
signal. Based on that at least one time-based signal trained neural network performs
a plurality of classification tasks. Based on the results of these classification
tasks, a classification result comprising at least a class corresponding to a non-defective
crimp result and a class corresponding to a defective crimp result is provided.
[0032] Such classification result can also be provided by the trained neural network; however
such classification result may also be generated outside of the trained neural network,
e.g. by rule-based and/or logic approach. In any way the determined classification
result of being a defective crimp result or a non-defective crimp result is based
on the classification performed by the trained neural network.
[0033] The term crimp result is not restricted to the actual connection of the crimped crimp
element and the conductor, but it can further comprise other results of the crimping
process that do not specifically relate to the properties of the crimped connection.
E.g. the term crimp result further comprises the assessment in terms of the situation,
if a crimping process can be performed or not due to presence or absence of a conductor
or a crimp element. The term defective or non-defective may therefore also be used
as classification term for the crimp process and not only to the crimped connection
of connector and crimp element.
[0034] The trained neural network may utilize a recurrent neural network, as such recurrent
neural network is of advantage for time-based signal analysis as such a recurrent
neural network is enabled to consider signals of the past. Also, a convolutional neural
network may be used advantageously, as the convolutional kernels can be configured
such to detect certain structures of interest in a time-based signal. A combination
of recurrent und convolution neural network may also be considered, especially of
a deep recurrent und convolution neural network, to combine the advantages of both
neural network approaches. It is understood that also other kind of neural networks
may be used for the classification.
[0035] The trained neural network is configured by training to classify the time-based signal
provided to the trained neural network and to provide a respective classification
result based on the classified time-based signal. Such trained neural network showed
reliable and robust classification results in terms of the at least one time-based
signal provided to the trained neural network.
[0036] The classification result provided by trained neural network at least comprises the
information, based on the analysis of the time-based signal, that a connection of
the crimp element and the conductor is classified as non-defective or defective. The
classification result can comprise further information related to the crimping process,
respectively to the associated crimping result. Especially, an output vector can be
provided by the neural network providing additional information on the crimping process.
[0037] Thus, the present invention makes use of a specially trained artificial neural network
performing a fault pattern recognition based on the at least one time-based signal
using the appropriately trained neural network.
[0038] The neural network is trained by means of corresponding training data sets. Such
training data sets are at least a plurality of time-based structure-borne sound signals,
whereas an associated crimp result is known. Dependent on the intended use, also other
types of time-based sensor signals may be used for training.
[0039] In the course of such training, the trainable neural network may be presented with
corresponding training data which has already been divided in advance into positive
training examples, e.g. a time-based signal resulting in a non-defective crimp result,
and negative training examples, e.g. a time-based signal resulting in a defective
crimp result. Further, the training data also comprises a corresponding classification
result. As mentioned, the classification result may comprise an information, if a
crimp result based on the associated at least one time-based signal is a defect or
non-defect crimp result.
[0040] Further the classification result may comprise more detailed information regarding
the crimping process, e.g. information to the quality of the crimp result, a certain
defect or other information. The information that shall be output by the trained neural
network when analysing a time-based signal needs to be provided to the neural network
in the training phase.
[0041] Such a training dataset may, for example, be generated manually from historical data,
for which the time-based signal was detected and the crimp result, especially defective
or non-defective, but e.g. also the error pattern of a defective connection of crimp
element and conductor, is known. The time-based signals required for training can
be derived easily as the crimping process can be monitored and the respective data
is normally stored. Further, the result of the crimping process is known.
[0042] In the following, an exemplary embodiment for the creation of a training data set
and the training of the neural network is described. It is understood that the described
creation and training of the neural network may also be performed independently, especially
offline at a separate computer that is not related to any manufacturing or crimping
process. The present disclosure therefore explicitly discloses such creation and corresponding
training as separate subject matter.
[0043] For an exemplary training of a neural network, at least 500 to 2000 time-based signals
for single crimp processes are used to train a specific classification result.
[0044] If a plurality of different time-based signals, e.g. from different sensors, especially
different types of sensors for detecting different types of time-based signals, the
number of training data sets increases accordingly.
[0045] I.e. the size of the training data set is typically dependent on the number of classification
results that shall be provided by the trained neural network as well as on the number
and types of time-based signals that shall be used by the neural network to determine
the classification result.
[0046] Respectively, a training providing a low level of training effort is e.g. based on
a time-based force signal and/or on a time-based structure-borne sound signal and
a classification result relating to the crimp result which shall only comprise the
information "defective" or "non-defective".
[0047] The analysis of time-based signals, especially of time-based force signals and/or
structure-borne sound signals, by a trained neural network is dependent from different
factors, e.g. the type of the time-based signal, number of data points comprised by
the time-based signal, the desired accuracy and the computational resources.
[0048] It is advantageous to pre-process the time-based signal, e.g. the time-based force
signal and/or the structure-borne sound signal or a plurality or combination of different
time-based signals, before they can be analysed by the neural network. Such pre-processing
may comprise normalization, scaling, and filtering data, especially to remove noise
and/or artefacts. The pre-processing of the time-based signals to be analysed by the
neural network may be performed by the neural network or may be performed conventionally,
i.e. without applying a neural network for the pre-processing.
[0049] Further the data should preferably made available to the neural network in such way
that they can be processed by the neural network. This is valid for applying the trained
neural network to at least one time-based signal related to the crimping process,
but as well for the training of an untrained or partially trained neural network with
respective training data.
[0050] Normally, the time-based signals are windowed in different time windows to capture
the time dependency of the time-based signal. This can be implemented e.g. by so called
rolling windows, which provide a fixed time window to capture a time-based signal
step by step.
[0051] The determined signal windows may then be organized in a respective matrix. Typically,
each line of the matrix corresponds to a signal window, whereas each column corresponds
to a point of time in this respective window. The size of the window and the overlap
of the time windows can vary.
[0052] Out of this matrix, vectors can be generated to provide input data for the neural
network. E.g. each vector can comprise the signal of each window in one line of the
matrix. In such case each line of the matrix would be an input vector for the neural
network.
[0053] If a recurrent neural network is used, the rolling windows is typically provided
as sequence of vectors. Each vector corresponds to one signal window. The signal windows
are then provided subsequently to the neural network, whereas the neural network generates
an output which is used as input for the next signal window.
[0054] Further the training data may comprise further data beyond at least one time-based
signal, especially beyond a plurality of time-based signals of different types. For
example such further data to be included in the analysis by the neural network may
related to the technical specification of the crimp device, the used material of the
crimp element, if known, the used crimping tool and, and other, especially technical,
parameters associated with the crimping process.
[0055] Further it may be considered for training of the neural network to manipulate the
measured time-based signals in such way that a classification result is not changed
but the parameter room for which the neural network is trained is increased. This
allows more reliable, robust, and stable operation of the trained network when applied
to at least one to time-based signals relating to the crimping process as the network
is enabled to handle variations, which were not contained in the unmanipulated training
data.
[0056] After respective preparation of the time-based signal or plurality of time-based
signals, the neural network is trained with a share of the training data sets, e.g.
66%. The remaining training data sets, e.g. 34%, are used to later check the performance
of the neural network, i.e. the time-based signal of these training data sets is provided
to the trained neural network and the classification result is checked versus the
known crimp result. This share of training data may also be denoted as test data or
verification data. This approach is used to avoid overfitting.
[0057] After the training is finalized the quality of the training may be determined by
feeding the test data to the trained neural network. In case the quality of the classification
results is sufficiently accurate, the training is stopped. In case the classification
results do not reach the desired accuracy level the training can be continued with
respective training data and/or be started with amended parameters.
[0058] It needs to be understood that the training can be implemented in different ways
dependent on the utilized neural network. Basically, each kind of training of the
neural network adapts the internal weights of the neural network in such way, that
the deviation of the classification result to the known result from the training data
is minimized. This is typically implemented by the so-called backpropagation optimization
of the neural network.
[0059] For the training, a so-called epoch number can be determined as well as an abortion
criterion. The epoch number reflects the number of training cycles. For each training
cycle a defined number of training data can be used, e.g. the entire training data
or a subset of the training data. The abortion criterion determines the acceptable
deviation of the classification result from the ideal, respectively known, result.
In case the abortion criterion is reached, the training is stopped, and the neural
network is considered as sufficiently well trained.
[0060] The usable trained neural network, especially a deep recurrent neural network, may
comprise an input layer, a plurality of hidden layers and an output layer. The hidden
layers may comprise at least partly identical layers or repeating layer structures.
Especially the neural network may comprise several processing blocks dedicated to
a specific task.
[0061] In the following a schematic layout of the neural network is described.
[0062] In the input layer, the time-based signal or plurality of time-based signals are
provided to the input layer of the neural network. Furthermore, other data or parameters
that influence the crimping process may be provided to the input layer in combination
with the time-based signal or the plurality of time-based signals, especially of different
types.
[0063] The other data provided to the neural network can be machine parameter, providing
e.g. positions, velocities, used die for a crimping tool front end, known material
parameters of the crimp element. In addition, further parameters might be considered
as input for the neural network that are e.g. of importance for subsequent manufacturing
steps of the crimped connection.
[0064] After the input, several processing blocks can be considered for processing the input
data. Such blocks can comprise a pre-processing of input data for the respective block,
e.g. the input data can be pre-processed in terms of time-wise normalization or amplitude.
The windowing of the time-based signal can be varied; further a sub-sampling of the
time-based signal can be provided to reduce the signal without losing information,
e.g. to cancel noise or other defined frequency ranges. It is further possible to
determine a root mean square, especially without filtering, which is a measure for
the amplitude over a certain time period. Also, a principal component analysis can
be provided to reduce the dimensions of the data, but to keep characteristic information
in the data set. E.g. also zero padding layer can be provided, a layer for convolutional
operations, a layer for normalization, layers for activation via a so-called ReLU
function, also denoted as rectified linear unit, can be utilized and others.
[0065] The pre-processing can be provided by the neural network, if specifically trained
for that task. However, the pre-processing of data may also be performed outside the
neural network with a conventional method.
[0066] For the classification task itself different tools can be utilized, whereas the use
of the respective tool can depend on the actual task that shall be performed on the
data.
[0067] For example, HDBSCAN, which is an abbreviation for hierarchical density-based spatial
clustering of applications with Noise, can be used. This is a clustering algorithm,
which is used to identify clusters in a data set comprising complex data structures.
Such identified clusters can be used for further analysis by other processing blocks.
[0068] A one-class support vector machine, abbreviated OCSVM, can be used to identify anomalies
from the operation data, i.e. based on the at least one time-based signal, of the
crimp device. The anomaly detection is based on the training data which is defined
as non-anomaly data. An anomaly is detected, if analysed data is sufficiently distant
in the data room from the training data. This approach allows to detect anomaly events,
especially heavy or severe anomalies in the crimping process, without having information
or training data on a respective anomaly. This can also be provided by HDBSCAN in
isolation or by a combination of OCSVM and HDBSCAN, whereas the combination of OCSVM
and HDBSCAN further improves an anomaly detection. Especially, anomalies are typically
rare and normally not sufficient training data is present to detect anomalies by training
with anomaly data. With this tool, it is possible to detect heavy or severe anomalies
in the operation of the crimp device without training data for the anomaly itself.
[0069] Another suitable tool that can be applied is a traditional support vector machine.
By means of a support vector machine the classification in a plurality of classes
can take place as given by the training data. Such tool can be used for a processing
block which classifies certain defects within a group of defects trained to the neural
network.
[0070] Another helpful approach can be a forest of randomized decision tree, also called
random forest. This is an ensemble model in the field of machine learning that combines
multiple decision trees, each trained on a different subset of the training data and
makes predictions based on the collective output of these trees. Each decision tree
is trained randomly. The decision trees in a random forest are constructed using a
random subset of features and a random subset of the training data. This helps to
reduce overfitting and increase the diversity of the trees in the forest. This leads
to model which is more robust and generalizes in a better way on unlearned data. During
training, the algorithm constructs a large number of decision trees and aggregates
their outputs to make the final prediction. The random forest approach is of advantage
in case of missing training data. It provides a high accuracy and is easy to implement.
[0071] Another advantageous approach is using an extreme learning machine, abbreviated ELM,
within the processing blocks of the neural network. ELM is a supervised machine learning
model to generate an output based on a certain input and belongs to the family of
feedforward neural networks. ELMs have the special configuration that neurones of
a hidden layer are randomly initialized, followed by a linear regression to adapt
the output of the hidden layer to the desired output vector. In contrast to traditional
neural networks, whose weights are optimized in an iterative way, the weights of an
ELM are adapted much faster, typically in one step. ELMs are typically easer to implement
and to train than traditional feed forward neural networks.
[0072] An exemplary ELM to implement the invention used one hidden layer of tanh (tangens
hyperbolicus)-activated ELM neurons and further neurons copying the input. The input
layer comprised 500 neurons, the hidden layer comprised 256 neurons with tanh-activation
and copying neurons. The output layer comprised one neuron.
[0073] Another approach that can be used in context of the invention is the use of a multilayer
perceptron, abbreviated MLP, which is also a supervised-machine learning model, typically
utilized for classification and regression problems. An MLP is a specific embodiment
of a feed forward neural network. An MLP comprises at least an input layer, an output
layer and at least one hidden layer, typically a plurality of hidden layers, arranged
between input layer and output layer. Each neuron in one layer is connected to all
neurons of a following layer, however not with neurons of the same layer.
[0074] In an MLP the input values are guided from the input layer to the at least one hidden
layer to the output layer. Each neuron in a hidden layer uses a weighted sum of its
inputs and outputs a value dependent on the sum of inputs and the applied activation
function. By training on the training data, the weights of the connected neurons are
adapted such that the deviation from the known result and the result provided by the
MLP is minimized. Typically, this is implemented via a backpropagation algorithm.
[0075] It has shown that the invention can be realized by using several processing blocks
comprising an input layer of more than 500 neurons, 4 hidden layers, whereas the first
layer comprises 256 neurons with a ReLU activation, the second hidden layer comprises
64 neurons with a ReLU activation, the third hidden layer comprises 16 neurons with
a ReLU activation and a fourth hidden layer of 4 neurons with ReLU activation and
an output layer comprising 1 neuron.
[0076] The approaches and tools described above can be used single or in combination to
implement specific functionalities of a processing block, respectively to implement
an embodiment of the invention.
[0077] The trained neural network may be configured such that following process is realized.
[0078] After the input of the data, an analysis of machine and sensor parameters can be
provided to identify heavy failures in the process.
[0079] The provided input data can then be processed by the trained neural network to classify
the crimp result on the provided input data. The neural network may comprise different
functional blocks to perform different tasks on the input data.
[0080] A first functional block may concern an anomaly detection. There may also be a plurality
of functional blocks for anomalies, e.g. a first block concerned with the detection
of heavy anomalies and second block concerned with the detection of light anomalies.
These can e.g. be implemented by utilizing the one-class support vector machine.
[0081] Another functional processing block may assess the feed adjustment for the element
to which the crimp element shall be crimped. A further functional processing block
may assess the presence of the cable, respectively the conductor, in the crimp device.
Another functional processing block may assess the cable feeding position based on
the input signal. Another functional processing block may assess the complete capture
of the strands during the crimping process based on the input signal. A further functional
processing block may assess a crimp height adjustment. Another functional processing
block may assess the crimp height and/or crimp width.
[0082] The results of these functional processing blocks may then be assembled to the classification
result of a defective crimp result or a non-defective crimp result. This can e.g.
be done via another processing block of the neural network or by logical combination
of the results provided by the respective previous functional processing blocks of
the neural network.
[0083] Further an output vector can be provided with additional information, e.g. regarding
the kind of the determined defect. This output vector may also comprise the reporting
of the functional blocks from which results were provided, especially the respective
results of these functional blocks.
[0084] The outputs of the pre-processing processing blocks and the classification processing
blocks may be combined as linear combination with weights from the input and/or can
be processed by other functional blocks comprising machine learning algorithms to
generate the output.
[0085] Based on the result of the classification a control signal is generated and provided
as output. Such control signal can be used to provide information on the classification
result to user interface, e.g. a display or monitor. Further the control signal can
be used as input signal for a control unit to control the crimp device based on the
provided control signal.
[0086] In an embodiment the at least one time-based signal comprises a time-based force
signal related to the force applied to a crimp element by the crimping tool, whereas
the at least one time-based force signal is detected for a defined time period comprising
a contact phase of the crimping tool and the crimp element. By monitoring the temporal
course of a force signal related to the crimping force another valuable parameter
is utilized highly relevant for the crimping process and the crimping result. Especially
the force signal provides a temporal course of the force during the contact phase
of the crimping tool and the crimp element. The phase of contact of the crimping tool
and the crimp element is especially critical for the crimping process and its result.
For this reason, time-based signals covering this period are especially valuable for
the determination of the crimp result. It has shown that the crimping process can
be assessed sufficiently reliable in case the at least one time-based signal is configured
as at least one time-based force signal.
[0087] In an advantageous embodiment, the force sensor, e.g. a load cell, is arranged at
the crimping tool, especially between the crimp press and the crimping tool front
end. The force sensor may also be arranged at a different position suitable to detect
a time-based force signal related to the crimping force. It has shown that the use
of a time-based force signal shows good results for determining a crimp result based
on such time-based force-signal analysed via a respectively trained neural network.
[0088] In a further embodiment at least one time-based structure-borne sound signal detected
at the crimping tool and/or at the crimp anvil and/or at the crimp anvil support,
whereas the at least one time-based signal of structure-borne sound is detected during
a relative movement of the crimping tool and the crimp anvil for a defined time period
comprising a contact phase of the crimping tool and the crimp element.
[0089] It has shown that the crimping process can be assessed sufficiently reliable in case
if the at least one time-based signal is configured to be a at least one time-based
structure-borne sound signal. Such at least one time-based structure-borne sound signal
may be detected at the crimping tool and/or the crimp anvil and/or the crimp anvil
support.
[0090] The time-based signal of structure-borne sound is preferably detected during a relative
movement of the crimping tool and the crimp anvil for a defined time period comprising
a contact phase of the crimping tool and the crimp element. This means the time-based
signal of structure-borne sound is directly related to the crimping process as the
time period in which this signal is detected covers the actual crimping of the crimp
element. The temporal course of the structure-borne sound signal is directly related
to the interaction of the crimping tool and the crimp anvil as well as to the crimp
element/conductor configuration arranged between the crimping tool and the crimp anvil.
[0091] The at least one time-based signal of structure-borne sound can be detected at the
group selected from the crimping tool, the crimp anvil, and the crimp anvil support.
The crimp anvil support is the support structure supporting the crimp anvil. As the
crimp anvil support is also arranged closely to the actual deformation process of
the crimp element, the crimp anvil support is also suitable for arranging at least
one sensor configured to detect a time-based structure-borne sound signal.
[0092] At least one respective sensor to detect a time-based structure-borne sound signal
can be arranged at the crimping tool, especially at the crimping tool front end, e.g.
in the environment of the non-exchangeable part, i.e. preferably not at a crimping
die. As alternative or in addition, the respective sensor to detect a time-based structure-borne
sound signal can be arranged at the crimp anvil and/or at the crimp anvil support.
[0093] It is advantageous to arrange a respective sensor to detect a time-based structure-borne
sound signal as close as possible to the spatial area, in which the actual crimping
of the crimp element takes place. This provides a low degree of relay of the signal;
further the signal is only influenced negligibly from other sources than the actual
crimping process, and the amplitudes of the detected signal associated with the crimping
process are comparably high.
[0094] The accuracy can be improved, in case the crimping tool front end and the crimp anvil,
or instead of the crimp anvil the crimp anvil support, comprise both at least one
respective sensor to detect a time-based structure-borne sound signal. It is further
advantageous, if such at least one first and at least one second sensor are configured
to detect a structure-borne sound signal in differing frequency ranges, e.g. for a
high frequency range and for a low frequency range of structure-borne sound signals.
This further improves the accuracy of the determined crimp result, as additional information
on the crimping process is provided by monitoring differing frequency ranges.
[0095] In a preferred embodiment a combination of two types of time-based signals, which
is at least one time-based structure-borne sound signal and at least one time-based
force signal, are used for the classification of the crimp result by the respectively
trained neural network.
[0096] By utilizing such combination of at least one time-based structure-borne sound signal
and at least one time-based force signal, the accuracy of the classification result
can be significantly increased. For this specific configuration, the trained neural
network is trained accordingly at least on the basis of the combination of these two
types of time-based signals.
[0097] In a further embodiment the at least one time-based signal comprises a time-based
position signal for the crimping tool relative to the crimp anvil, whereas the at
least one time-based position signal is detected for a defined time period comprising
a contact phase of the crimping tool and the crimp element. Such temporal course of
the position signal of the crimping tool, especially of the crimping tool front end,
relative to the crimp anvil provides further information on the crimping process.
A relative position of the crimping tool to the crimp anvil shall be understood broadly.
In a known spatial configuration of the position of the crimping tool and the crimp
anvil no position difference needs to be given. It is sufficient to measure an absolute
position of the crimping tool if the absolute position of the crimp anvil is known
in the same reference system.
[0098] Such time-based position signal of the crimping tool relative to the crimp anvil
may be determined directly or indirectly. A direct way would be a position sensor
that determines the position of a reference point of the crimping tool, especially
the crimping tool front end, relative to a known and spatially fix reference point.
E.g. a distance sensor can be used that measures the distance of the crimping tool
to a fix reference point, e.g. arranged at a support frame for the crimping tool supporting
the crimping tool.
[0099] Also an indirect way of measuring the position of the crimping tool to the crimp
anvil may implemented e.g. by measuring parameters of the motor moving the crimping
tool. E.g. angles, motor positions and/or the motor load of the crimp press can be
used to determine the position of the crimping tool relative to the crimp anvil. Also,
other parameters may be utilized for an indirect determination of the position of
the crimping tool to the crimp anvil.
[0100] In case the time-based position signal is utilized in combination with the time-based
force signal and/or time-based structure-borne sound signal and/or in combination
with at least one of the other types of time-based signals the accuracy of the classification
result based on such combination of different types of time-based signals is improved.
[0101] Especially the detection period, i.e. the time-period over a which a time-based signal,
especially the at least one structure-borne sound signal and/or the at least one time-based
force signal, is captured or detected by a respective sensor, can be controlled on
basis of the time-based position signal. This allows to focus the detection period
on a time-period of the crimping process relevant to characterize the crimping result.
In such case the trained neural network is trained to determine a classification and
the respective result based on such combination of different types of time-based signals,
which may also include the time-based position signal.
[0102] In a further embodiment the at least one time-based signal comprises a time-based
acceleration signal detected at the crimping tool and/or the crimp anvil, whereas
the at least one time-based acceleration signal is detected for a defined time-period
comprising a contact phase of the crimping tool and the crimp element. It is understood
that a structure-borne sound signal is a specific embodiment of an acceleration signal.
However, also other time-based acceleration signals that are no time-based structure-borne
sound signals, can be used to further improve the monitoring of the crimp process.
Such acceleration signals may be related e.g. to vibrations of the crimping tool,
e.g. originating from the motor-driven movement, or may be associated with a gear,
which may influence the crimping process.
[0103] The consideration of such time-based accelerations signal, especially a time-based
accelerations signal, which is not a time-based structure-borne sound signal, by the
trained neural network may further improve the accuracy of the classification result.
[0104] Such time-based acceleration signal may be used in combination with the time-based
force signal and/or the time-based structure-borne sound signal alone and/or in combination
with one of the other types of time-based signals described above.
[0105] In a further embodiment the at least one time-based signal comprises at least one
time-based elongation signal detected at a support frame supporting the crimping tool,
whereas the at least one time-based elongation signal is detected for a defined time-period
comprising a contact phase of the crimping tool and the crimp element. The elongation
as well as a compression, which is a negative elongation, of the support frame to
which the crimping tool is mounted, may have influence on the crimping result as well.
By applying the respective crimping forces to the crimp element, the support frame
may change its physical configuration leading to varying crimp results. It is therefore
advantages to provide at least one sensor at the support frame to detect a time-based
elongation signal of the support frame during the crimping process.
[0106] It may be advantageous to detect a plurality of time-based elongation signals, whereas
each time-based elongation signal of the plurality of time-based elongation signals
is detected at a different position at the support frame. This allows to better consider
the influence of the support frame to the crimping process, especially to the crimp
results, as the support frame may react differently for different crimping process
configurations.
[0107] Considering such at least one time-based elongation signal for the classification
by the respectively trained neural network further improves the accuracy of the classification
result.
[0108] Such at least one time-based elongation signal of the support frame may be used in
conjunction with a time-based structure-borne sound signal and/or a time-based force
signal alone and/or in combination with at least one of the other types of time-based
signals specified above, e.g. the at least one time-based position signal and/or the
at least one time-based accelerations signal. Dependent on the specific use of the
combinations the neural network is trained correspondingly to determine a classification
and a classification result on provided time-based signals.
[0109] In another embodiment at least one temperature signal is detected during the crimping
process, especially for a defined time-period comprising a contact phase of the crimping
tool and the crimp element, and provided to the trained neural network, whereas the
trained neural network is configured to consider the at least one temperature signal
for classifying a result of a crimping process based on the received at least one
time-based signal and the at least one temperature signal.
[0110] The temperature may have an influence on the crimp result as the properties of the
used materials, e.g. the crimp element, may have temperature-dependent properties.
It is therefore also of advantage to take the temperature during the crimping process
into consideration and base the classification of the respectively trained neural
network also on the temperature. Especially, due to a slow temperature change or temperature
drift over a plurality of cycles of crimping processes the crimping result may be
affected by the temperature change, although the other parameters may be maintained.
[0111] Temperature changes during a single crimping process have shown to be less relevant;
this is related to the fact that the time period of a single crimping process, especially
of the contact phase of the crimping tool and the crimp element, is comparably short
to the time scales of thermodynamic processes in the environment affecting a temperature
change. However, temperature changes over a plurality of crimping processes have shown
to be a relevant parameter. In a specific embodiment the at least one time-based signal
comprises a temperature signal, i.e. the temperature signal is configured to be a
time-based temperature signal, detected during the crimping process, especially for
a defined time-period comprising a contact phase of the crimping tool and the crimp
element. In this case a temporal course of a temperature signal detect during the
crimping process is provided to the trained neural network. In another embodiment
only one temperature detected during the crimping process is provided to the trained
neural network and used for determining the classification result.
[0112] Also, such temperature signal, especially time-based temperature signal may be used
with the time-based force signal and/or time-based structure-borne sound signal alone
and/or in combination with at least one of the other types of time-based signals specified
above, e.g. the at least one time-based position signal, the at least one elongation
signal and/or the at least one time-based acceleration signal. Dependent on the specific
use of the combinations the neural network is trained correspondingly to determine
a classification and a classification result on the provided data basis.
[0113] In a further embodiment the detection of at least one time-based signal is triggered
by a triggering signal detected by a trigger sensor, especially whereas the trigger
signal is generated dependent on a predefined position of the crimping tool relative
to the crimp anvil. The trigger signal can be applied to any type of the detected
time-based signals. The trigger signal may define a measurement window for the detection
of time-based signals. Especially a starting point can be provided by the trigger
signal, as well as an endpoint. Alternatively, a specified period of time for the
detection of a time-based signal can be used.
[0114] The use of such trigger signal provides a focus on the relevant data for the crimping
process and therefore avoids the capture of data not valuable for the classification
of a crimp result. E.g. such measurement window for at least one of the types of time-based
signals is started shortly before the contact phase of the crimping tool with the
crimp element and stopped short after the crimping tool has been removed from the
crimping tool. In total such measurement window may be between 10ms and 500ms.
[0115] In an advantageous embodiment all utilized time-based signals, especially also the
time-based temperature signal, have the same measurement window initialized by the
triggering signal. Especially the position signal of the crimping tool can be utilized
as triggering signal for the group of time-based signals selected from the time-based
structure-borne sound signal, the time-based force signal, the time-based position
signal, the time-based acceleration signal, the time-based elongation signal, a time-based
temperature signal. E.g. the detection period for all time-based signals referenced
before can be started as soon as the position signal reaches a trigger position initiating
a measurement cycle for all relevant sensors.
[0116] In a further embodiment the control signal is provided with a repetition rate of
2 seconds or less, especially of one second to 0,5 seconds. With such repetition rate
a real-time monitoring of the crimp result can be provided based on such control signals
as well as a real-time control of the crimp device based on such control signal.
[0117] In an embodiment the classification result further comprises a crimp quality indicator,
e.g. the crimp height or the crimp width, related to the quality of a crimped connection
of the crimp element and the conductor, especially in case the crimp connection is
classified as non-defective.
[0118] The crimp quality indicator gives a more specific information to the crimp result,
especially for every manufactured and monitored crimped connections. Especially in
case the crimped connection is classified as defective the crimp quality indicator
can be used to determine if the crimped connection can be corrected or not. In case
the crimped connection is non-defective, the crimp quality indicator can be monitored
for non-defective crimp results and information is provided on mean values and the
root mean square deviation can be determined for non-defective crimp results. Such
crimp quality indicator may be displayed on a monitor or may be used as input for
a control unit of the crimp device.
[0119] Such crimp quality indicator, e.g. the crimp height and/or the crimp width, allows
especially to continuously monitor the output of the crimping process for every crimped
connection.
[0120] Conventionally, the quality of a crimped connection is checked only by taking random
or regular samples from the manufacturing process. E.g. for every 100 or 1000 manufactured
crimped connections one crimped connection is analysed conventionally, i.e. outside
of the manufacturing process, for checking the crimp quality, e.g. crimp height and/or
crimp width, generated by the crimping process. During the analysis of the crimped
connection, typically supported by a test facility, the manufacturing process for
other crimped connections continues. In case the crimp quality is not sufficiently
high for the test sample, further crimped connections not satisfying the desired quality
standard are manufactured while the analysis of the test sample takes place. This
is disadvantageous for the manufacturing efficiency. Further, it is impossible by
the conventional approach to monitor the crimp quality indicator for each and every
crimped connection without significant disadvantages regarding the manufacturing process,
especially regarding throughput.
[0121] Therefore, in a further embodiment, the crimp quality indicator is determined for
a plurality of subsequently manufactured crimped connections, whereas between each
crimped connection from the plurality of subsequently manufactured crimped connections
less than 100, especially less than 50, especially less than 10, especially less than
1, crimped connections are manufactured for which no crimp quality indicator is determined.
The limitation less than 1 equals to the fact that for every crimped connection of
the plurality of crimped connections a crimp quality indicator is determined.
[0122] By utilizing an embodiment of the presented method to determine as classification
result for a crimp quality indicator based on at least one time-based signal related
to the crimping process, the throughput of the manufacturing line is not affected
although the crimp quality can be determined for every crimped connection.
[0123] By providing a respectively trained neural network utilizing at least one time-based
signal, a crimp quality indicator can be provided e.g. for each crimped connection
providing much more close monitoring on manufactured crimp connections and the crimping
process. This enables a real-time control of the manufacturing process for crimped
connections.
[0124] In a further embodiment, the crimp quality indicator is detected over time, i.e.
a temporal course of the crimp quality indicator is captured, and analysed, whereas
based on such analysis a crimp quality control signal, especially in case the quality
control indicator decreases below a defined minimum quality indicator threshold, is
generated on which the operation of the crimp device is controlled such by means of
the quality control signal that the crimp quality indicator increases for a crimped
connection to be crimped by the crimp device. Such minimum quality indicator threshold
can be determined such that the respective a classification result for a crimp result
having such minimum quality indicator threshold is not determined to be "defective".
This allows to influence the crimping process before a crimp result is determined
to be defective.
[0125] Influencing a crimping process on basis of such crimp quality control signal assures
that the crimp quality indicator remains comparably constant within a desired range
providing high quality crimped connections.
[0126] The control signal generated on basis of the classification result may comprise such
crimp quality control signal.
[0127] In a further embodiment the classification result further comprises a failure indicator
allowing the identification of a certain defect from a plurality of defects identifiable
by the trained neural network for the crimped connection of the crimp element and
the conductor in case the crimped connection is classified as defective. Such failure
indicator may relate to the crimping process or to the crimped connection itself.
Especially, such failure indicator provides information on the kind of defect as classified
by the trained neural network, especially of the crimped connection. Such crimp failure
indicator can be descriptive for a user and/or can be the basis of a specific control
signal dependent on the failure indicator. Such failure indicator provides the possibility
to control the crimp device individually based on the detected failure. Therefore,
a control signal corresponding to the failure indicator may be used as input for a
control unit of the crimp device. Such failure indicator may also be displayed on
a monitor to be perceivable by respective personal.
[0128] In a further embodiment the classification result further comprises a data anomaly
indicator in case no identification of a certain defect from a plurality of defects
identifiable by the trained neural network for the crimped connection of the crimp
element and the conductor can be determined in case the crimp connection is classified
as defective. Such data anomaly indicator allows to capture crimp results classified
as defective, whereas the defect cannot be identified. Such anomaly indicator allows
to collect data on defects that are not yet part of the training data of the neural
network. Especially, such kind of defects may be monitored or investigated manually
by respective personal.
[0129] In a further embodiment plurality of identified anomalies and/or a plurality of identified
data anomaly indicators are clustered in clusters of anomalies. Such clusters of anomalies
can be used to further train the trained neural network for a new type of defect associated
with the identified anomalies and/or the identified anomaly indicators. Especially,
such training can be provided if the number of anomalies within a certain cluster
exceeds a certain threshold, meaning that a certain defect is detected sufficiently
often to justify and/or enable a re-training of the neural network on such anomaly,
respectively on that new kind of defect.
[0130] In a further embodiment the crimp device is controlled based on the control signal
in such way that the crimping process, especially at least one control parameter to
influence the operation of the crimp device, is changed such that a non-defective
crimp connection comprising a crimp element and a conductor to be processed is created.
Such at least one parameter of the crimping process is a parameter influencing the
crimping process and its result. Typically, such at least one parameter is at least
one actuating parameter of the crimp device, e.g. the crimping force applied by the
crimping tool, the motor speed, motor torque, speed and/or acceleration of the crimping
tool, spatial adjustments, etc.
[0131] Using the control signal in such way allows a control, especially a closed-loop real-time
control, of the crimp device. This can be used to achieve a stable operation of the
crimp device and a stable production of crimp connections with such crimp device.
[0132] The present invention relates further to a machine readable program code comprising
control commands, which initiate in case of their execution a method according to
one of the method claims. Such machine readable program code can be accessed via a
remote storage or a local storage, e.g. comprised by a control unit of the crimp device.
[0133] Another embodiment of machine readable program code may comprise control commands,
which are configured to provide a detected time-based signal to a trained neural network,
whereas the trained neural network is configured to classify a result of a crimping
process based on the received at least one time-based signal, whereas the classification
result comprises at least a class of a non-defective and a class of a defective crimp
result, and to provide a corresponding classification result, whereas a control signal
is generated and provided as output based on the determined classification result.
This machine-readable program code can be provided locally or may be accessed on a
remote server, e.g. accessible via an interface to a cloud infrastructure.
[0134] The invention further relates to a control unit comprising machine readable program
code, whereas the program code comprises control commands, which initiate in case
of their execution a method according one of the method claims.
[0135] The invention may further relate to a control unit comprising machine readable program
code, whereas the machine readable program code comprises control commands configured
to provide a detected time-based signal, e.g. at least one time-based force signal
and/or at least one structure-borne sound signal, to a trained neural network, whereas
the trained neural network is configured to classify a result of a crimping process
based on the received at least one time-based signal, whereas the classification result
comprises at least a class of a non-defective and class of a defective crimp result,
and whereas the trained neural network is configured to provide a corresponding classification
result and to provide a control signal as output based on the determined classification
result, whereas the control unit is configured to receive such control signal from
the trained neural network. The trained neural network can be configured to provide
as classification result the respective indicators, especially a crimp quality indicator,
a failure indicator, etc., as described above.
[0136] The trained neural network can be utilized via a cloud infrastructure. In this case
the control unit provides the time-based signal to and only an input signal is provided
based on the detected time-based signal, e.g. a time-based force signal and/or time-based
structure-borne sound signal, to an interface to provide it to the neural network.
The neural network then provides back the respective control signal via the interface
to and can use this control signal e.g. controlling the crimp device or displaying
the classification result. However, the trained neural network may also be provided
locally, especially in a storage of the control unit.
[0137] The invention further relates to a crimp device comprising a crimping tool and a
crimp anvil, further comprising at least one sensor to detect at least one time-based
signal during a crimping process, further comprising a control unit according to claim
15 and whereas the at least one sensor is connected to the control device. The crimp
device may especially comprise at least one sensor of the group of sensors: sensor
for detecting a structure-borne sound signal, sensor for detecting a time-based force
signal, sensor for detecting a time-based position signal of the crimping tool relative
to the crimp anvil, sensor for detecting a time-based acceleration signal, sensor
for detecting a time-based elongation signal, sensor for detecting a time-based temperature
signal, sensor for triggering a sensor for detecting a time-based signal. The presence
of the specific sensor types comprised by the crimp device shall correspond to the
types of time-based signals used for the analysis of the crimp process by the trained
neural network.
Brief description of the drawings
[0138] For a more complete understanding of the present disclosure and advantages thereof,
reference is now made to the following description taken in conjunction with the accompanying
drawings. The disclosure is explained in more detail below using exemplary embodiments
which are specified in the schematic figures of the drawings, in which:
- Figure 1
- a schematic illustration of a crimp device according to the invention in a first exemplary
configuration,
- Figure 2
- a schematic illustration of a crimp device according to the invention in a second
exemplary configuration,
- Figure 3
- a schematic illustration of a crimp device according to the invention in a third exemplary
configuration,
- Figure 4
- an aggregation of time-based signals usable by the trained neural network to determine
a classification result,
- Figure 5
- a flowchart showing a flow of method steps according to an exemplary embodiment of
the method.
[0139] In the figures like reference signs denote like elements unless stated otherwise.
Detailed Description of the drawings
[0140] Figure 1 shows a first embodiment of a crimp device 100, which is enabled to implement
an embodiment of the invention, especially to classify a crimp result based on a time-based
signal captured during the crimping process.
[0141] The crimp device 100 comprises a crimping tool 110 and a crimp anvil 120. The crimping
tool 110 further comprises a crimping tool front end 111 and a crimp press 112. The
crimping tool 110, or at least a part of the crimping tool front end 111, is movable
relative the crimp anvil 120, typically with a motor, not shown.
[0142] To crimp a contact C to a crimp element CE the crimping tool front end 111 is pressed
on the crimp anvil while the overlapping part of the contact C and the crimp element
CE are arranged between the crimping tool front end 111 and the crimp anvil 112.
[0143] By applying sufficiently high pressure to the contact C and the crimp element CE,
these components C and CE are attached to each other by cold forging. The crimping
tool front end 111 may have exchangeable tool attachments, also called dies, to be
adapted for the processing of different crimp process configuration, e.g. due to different
diameters, different materials, different crimp configurations, etc.
[0144] The relative movability of the crimping tool 110 relative to the crimp anvil via
a motor of the crimp press is shown in Figures 1 to 3 by a respective arrow AR.
[0145] According to Figure 1 the crimping tool 111 and the crimp anvil 120 are supported
at a support frame 300. It is not necessary that the crimping tool 111 and the crimp
anvil 120 are supported at the same frame 300. However, as the crimping process is
sensitive to the lateral relative position, i.e. in the direction in the sheet level
perpendicular to the shown arrow, of the crimping tool front end 111 and the crimp
anvil 120, supporting and adjusting the crimping tool 110 and the crimp anvil 120
at the same support frame 300 may have advantages.
[0146] Further, the crimp device 100 of Figure 1 comprises several sensor types. According
to Figure 1 two sensors are provided to capture a time-based signal of the crimping
process.
[0147] As a first sensor the crimp device 100 comprises a sensor 200 configured detect a
time-based structure-borne sound signal. This sensor 200 configured to detect a time-based
structure-borne sound signal is attached to the crimping tool front end 111, especially
within the last third of the crimping tool front end 111. This allows a good capture
of the structure-borne sound generated by the crimping process, especially during
the contact phase of crimping tool front end 111 with the crimp element CE, especially
in the deformation phase of the crimp element CE, via the sensor 200.
[0148] In addition or as alternative, such sensor configured to detect a time-based structure-borne
sound signal may be arranged at the crimp anvil 120. Such arrangement at the crimp
anvil 120 or in its vicinity, e.g. at the crimp anvil support, also provides a low
spatial distance to the actual crimping process of the crimp element CE and allows
a good capture of a time-based structure-borne sound signal related to the crimping
process.
[0149] It shall be noted that at least two sensors configured to detect a time-based structure-borne
sound signal can be present, where each of these sensors detects a different frequency
spectrum. This can be an overlapping frequency range or may be not-overlapping frequency
ranges, i.e. distinct frequency ranges. The at least two sensors may be arranged at
different positions at the crimp device 100, especially at different components of
the crimp device 100, e.g. the crimping tool 110, especially the crimping tool front
end 111, the crimp anvil 120 and/or the crimp anvil support 121.
[0150] E.g. a first sensor configured to detect a time-based structure-borne sound signal
may be configured to detect only frequencies above a certain threshold frequency,
whereas a second sensor configured to detect a time-based structure-borne sound signal
may be configured to detect only frequencies below a certain threshold frequency.
Different frequency ranges may provide additional information in terms of the course
of the crimping process and therefore can be advantageous for determining a crimp
result based on such signals relating to different frequency bands.
[0151] The crimp anvil 120 provides a counter pressure to the force applied by the crimping
tool 111 to realize a deformation of the crimp element CE, when force is applied on
the crimp element CE positioned on the crimp anvil 120, and therefore a secure connection
of the crimp element CE with the conductor C is created.
[0152] As a second sensor the crimp device 100 comprises a sensor 210 configured to detect
a time-based force signal. The time-based force signal shall advantageously be related
as close as possible to the crimping force. The sensor 210 configured to detect a
time-based force signal may be realized as load cell, especially piezo load cell.
The sensor 210 configured to detect a time-based force signal is arranged such that
a time-based force signal can be detected that is related to the temporal course of
the crimping force applied to the crimp element CE.
[0153] Especially, such sensor 210 configured to detect a time-based force signal is arranged
between the crimping tool front end 111 and the crimp press 112 generating the crimp
force. Preferably, the time-based force signal related to the crimping force is the
time-based crimping force signal itself. Such force sensor 210 might also be arranged,
in addition or as alternative, at the crimp anvil 120.
[0154] During the crimping process both time-based signals of the respective sensors 200
and 210 are detected. Both time-based signals are captured during a time window comprising
at least the contact phase of the crimping tool 110 and the crimp element CE.
[0155] The contact phase starts when the crimping tool front end 111 gets in contact with
the crimp element CE, further comprises the period of deformation of the crimp element
CE and ends, when the crimper tool front end 111 is no longer in contact with the
crimped crimp element CE.
[0156] The sensor 200 configured to detect a structure-borne sound signal and the sensor
210 configured detect a time-based force signal are each connected to a control unit
500. The detected time-based signals are respectively provided to the control unit
500.
[0157] The control unit 500 is configured to analyse the crimping process based on the provided
time-based signals captured during the crimping process. For this purpose, the control
unit 500 comprises machine readable program code 400 to receive and/or retrieve the
time-based signals from the connected sensors.
[0158] Further the control unit 500 is enabled by the machine readable program code 400
to process the time-based signals from the respective sensors and to analyse these
by providing the time-based signals to a trained neural network. The trained neural
network is configured to classify a crimp result based on the time-based signals fed
to the trained neural network and is implemented correspondingly via the machine readable
program code 400.
[0159] Accordingly, a control signal is provided based on a determined crimp result when
the control commands comprised by the machine readable program code 400 are executed.
Such control signal can be used to control the crimp device and/or to provide an illustration
of the crimp result on a control display for respective personal.
[0160] The control signal may load the machine readable program code 400 in a local storage,
e.g. comprised by the control unit 500, or may provide the time-based signal to a
cloud infrastructure via a respective interface, whereas the analysis may then be
executed in the cloud. A classification result and/or a respective control signal
may be provided via an interface of the control unit 500 from the cloud.
[0161] However, as high reliability regarding the availability of the classification result
and the respective control signal as well as real-time monitoring capability is of
importance, a local set-up for accessing the machine readable program code 400 might
be preferable.
[0162] According to Figure 1 the crimping process is analysed on basis of the time-based
structure-borne sound signal and the time-based force signal captured during the crimping
process. Both signals are captured during at time window comprising at least the contact
phase of the crimping tool 110 and the crimp element CE.
[0163] It has shown that the combination of the temporal course of the structure-borne sound
signal and of the temporal course of the force signal provide very accurate classification
result and high reliability regarding the crimp result achieved by the crimping process
to which the respective signals are detected.
[0164] The detection period, i.e. a defined time period in which a respective time-based
signal is detected, comprises preferably the entire contact phase of the crimping
tool and the crimp element. The single values detected in the defined time period
shall be detected with a timely distance from each other that allows a reliable monitoring
of the crimping process. Preferably, the detection period for the two sensors 200
and 210 according to Figure 1 is configured as time window of 300ms to 500ms, whereas
subsequent measurement values of the respective sensors 200, 210 are detected with
a sampling rate of 1ms or less.
[0165] The detection of the time-based structure-borne sound signal and the time-based force
signal is constantly repeated such that it captures subsequently the consecutive single
crimping processes for the crimp elements over time. The control signal based on these
captured time-based signals is generated with repetition rate of less than 1s to allow
a real-time control of the crimping process, respectively the crimp device 100.
[0166] Figure 2 shows another embodiment of a crimp device 100 enabled to execute an embodiment
of the method according to the invention. The crimp device 100 is comparably similar
to the crimp device 100 according to Figure 1. However, the crimp device 100 according
to Figure 2 further comprises additional types of sensors configured to detect additional
types of time-based signals.
[0167] E.g. the crimp device 100 further comprises two sensors 230 configured to detect
a time-based elongation signal, also denoted as elongation sensor in the following,
of the support frame 300 during the crimping process. The elongation sensor 230 detect
a temporal course of an elongation signal of the support frame 300, especially during
the time when the crimping tool front end 111 contacts the crimp element CE. A deformation,
also only a slight deformation, of the support frame 300 during the crimping process
can influence the result of the crimping process. For this reason, including such
time-based signal into the analysis of the control unit is advantageous. The two sensors
230 configured to detect a time-based elongation signal are located at different positions
at the support frame 300.
[0168] Further the crimp device 100 according to Figure 2 comprises a first sensor 200 configured
to detect a time-based structure-borne sound signal and a second sensor 201 to detect
a time-based structure-borne sound signal. The first sensor 200 is arranged at the
crimping tool front end 111. The second sensor 201 is arranged in the vicinity, especially
at the crimp anvil support 121, of the crimp anvil 120. It may also be arranged at
the crimp anvil 120 itself.
[0169] In this configuration two independent time-based signals providing structure-borne
sound signals are available to be provided to the control unit 500, which can improve
the accuracy of the classification result, as additional information on the crimping
process from distinct parts of the crimp device 100 can be utilized. Further the first
and second sensor 200, 201 are configured to the detect structure-borne sound in different
frequency ranges.
[0170] Instead of the first or second sensor 200, 201 a sensor configured to detect a time-based
acceleration signal, which is not a structure-borne sound signal, may be provided
at the crimping tool 111 or at the vicinity of the crimp anvil 120, especially at
the crimp anvil support 121, or at the crimp anvil 120.
[0171] Further a sensor 220 configured to detect the relative position of the crimping tool
110 relative to the crimp anvil 120 is provided, which is denoted also as position
sensor 220 in the following. The position sensor 220 can be implemented as distance
measuring sensor.
[0172] Such sensor 220 can be arranged at the support frame 300. In terms of position measurement
the support frame 300 has a constant spatial position, whereas the crimping tool 110,
especially the crimping tool front end 111, moves relatively to that support frame
300. For that reason, it is suitable to arrange a position sensor 220 configured as
distance measuring sensor at the support frame 300.
[0173] Such sensor 220 can work optically or otherwise and determine the distance of a position
reference element 221 arranged at the crimping tool 110, especially at the crimping
tool front end 111. As sensor configured to detect a relative position of the crimping
tool 11 to the crimp anvil 120, also a motor parameter, e.g. its power load, angle,
or other parameter, of the crimping tool 111, especially of the crimp press 112, can
be used.
[0174] The relative position of the crimping tool 111 relative to the crimp anvil 120 can
advantageously be used as trigger to start a detection period of the other types of
sensors, e.g. the first and second sensor 200 and 201 configured the detect a time-based
structure-borne sound signal, the sensor 210 configured to detect a time-based force
signal, and other sensors for detecting a time-based signal related to the crimping
process. This can also apply to a temperature sensor 240, which is also present in
the crimp device 100 according to Figure 2 and detects a time-based temperature signal.
Such triggering of a detection period for several types of sensors 200, 201, 210,
230, 240 can be controlled by the control unit 500.
[0175] All sensors 200, 201, 210, 220, 230, 240 configured to detect time-based signals
related to the crimping process are connected to the control unit and the respective
time-based signals are provided to the control unit 500.
[0176] The trained network, to which the time-based signals are provided for classification
purposes is trained to determine a classification result based on all time-based signals
provided to the trained neural network. Such broad basis of time-based signal related
to the crimping process increases the accuracy of the determined crimp result determined
by the neural network.
[0177] Figure 3 shows another embodiment of the crimp device 100 suitable to determine crimp
results on time-based signals captured via different sensors 200, 201, 210, 220, 240.
[0178] The crimp device 100 according to Figure 3 comprises a first and a second sensor
200, 201, each configured to detect a time-based structure-borne sound signal during
the crimping process. The first sensor 200 and the second sensor 201 are configured
to detect time-based structure-borne sound signals, whereas the first sensor 200 detects
time-based structure-borne sound signals of a first frequency range and the second
sensor 201 detects time-based structure-borne sound signals of a second frequency
range. This allows e.g. to monitor a high frequency band for a time-based structure-borne
sound signal and at the same time a low frequency band for a time-based structure-borne
sound signal during the crimping phase, especially during a contact phase of the crimping
tool 111 with the crimp element CE. Such configuration provides additional information
on the crimping process.
[0179] Further the crimp device 100 according to Figure 3 comprises a sensor 210 configured
to detect a time-based force signal related to the crimping force, a temperature sensor
240 configured to detect a time-based temperature signal and a sensor 220 configured
to detect a time-based position signal of the crimping tool 111 comprising a position
reference element 221.
[0180] It has been shown that such configuration of plurality of sensors is especially advantageous
to determine an accurate classification result during the crimp manufacturing process.
[0181] Figure 4 shows a plurality of time-based signals, which can be acquired with a sensor
configuration of Figure 3. Two temporal courses of structure-borne sound signals are
shown in Figure 4 over time. A temporal course of the first structure-borne-sound
signal is denoted as SBS1, whereas a temporal course of the second structure-borne-sound
signal is denoted as SBS2.
[0182] SBS1 shows a temporal course of high frequency structure-borne sound, whereas SBS2
shows a temporal course of low frequency structure-borne sound. A further type of
time-based signal is provided, which is configured as temporal course of a force signal
F. Another type of time-based signal is provided, which is configured as temporal
course of a position signal P of the crimping tool. A further type of time-based signal
is shown, being a temporal course of the temperature signal T. The signals have an
amplitude A which is applied on the y-axis, whereas the time t is applied on the x-axis.
[0183] In Figure 4 further a frame FR is shown. The frame FR shows exemplarily the relevant
time period suitable to determine a classification result based on time-based signals
contained in this frame FR by providing these to the respectively trained neural network.
[0184] Further, it becomes visible from Figure 4 that reaching a certain position PT of
the crimping tool can be used to define a starting time T to start a detection period
delta t for several types of sensors, i.e. to start a detection period delta t for
each crimping process for all utilized sensors. The position signal P is especially
suitable to provide such trigger function. It is understood that such trigger function
is independent of the types of sensors to be triggered, i.e. all combinations of different
types and numbers for sensors or single sensors can be triggered via such trigger
function to start and/or end the detection period, respectively the measurement window.
[0185] The detection period delta t can end, when a predefined position of the crimping
tool is reached, e.g. when the trigger position PT is reached again after the crimping
process, i.e. when the crimping tool is moved back from the crimp anvil. The detection
period delta t may also be configured to have a fixed period, especially a fixed period
for all time-based signals. The detection period delta t for some or all the different
time-based signals can also be different and does not need to be necessarily the same.
[0186] Figure 5 shows a schematic flow diagram illustrating an exemplary embodiment of a
method according to the invention.
[0187] In a first step S0 a plurality of time-based signals is detected and provided to
the control unit. Based on Figure 4 such time-based signals can be a first and a second
structure-borne sound signal whereas the corresponding sensors focus on different
frequency ranges. Further a time-based force signal may be detected and provided to
the control unit.
[0188] In second step S1 the received data is checked by the control unit in terms of thresholds
relating to the provided sensor signals and other machine data. This check is supposed
to identify machine and sensor failures which do not allow a reasonable analysis.
This step can be provided in a conventional way or via the respectively trained neural
network.
[0189] In a third step S2 a further check of the provided is made regarding the presence
of a severe respectively heavy anomaly in the crimping process. Such heavy anomaly
detection is implemented via a respective machine learning algorithm which is part
of the trained neural network. In case a heavy anomaly is determined a respective
failure indicator is provided and the process is stopped. Such heavy anomaly detection
can e.g. be implemented via a one-class support vector machine.
[0190] In case no heavy failure anomaly is determined, a further check is made in a step
S3 regarding the presence of light anomalies. Light anomalies are known anomalies
in the crimping process which concern the crimp result comprising typical error patterns
or failure patterns. Such light anomaly detection can be implemented by a respective
machine learning algorithm, e.g., a support vector machine. In parallel the presence
of a conductor can be determined by the trained neural network based on the provided
data in a step S3'.
[0191] Subsequently, a several classification tasks may be performed in parallel by the
respectively trained neural network. These can also be performed subsequently. However,
due to the real-time control capability of the method a parallel process might be
preferred.
[0192] E.g. in a step S4 the crimp height adjustment of the crimping tool can be determined
by the respectively trained neural network. In parallel, in a step S4', the crimp
height of the crimped crimp element can be determined via the respectively trained
neural network. In addition, the respectively trained neural network also determines
the completeness of strands for the crimping process in step S4", i.e. it is checked
if all strands are inserted in the crimp element. Further, in a step S4‴ the position
of the conductor is determined by the respectively trained neural network.
[0193] In a step S5 the classification result is determined, which at least comprises a
class for a defective crimp result and or class for a non-defective crimp result.
Further, a vector can be provided with the classification result of the different
checks of steps S1 to S4'". The classification result of being at least a defective
crimp result or a non-defective crimp result can be derived via the trained neural
network or may derived outside the neural network e.g. by combining the classification
results of the previous step S1 to S4‴ according to valuation logic. This valuation
logic may then determine based on the provided classification results of the previous
steps, if a non-defective or a defective-crimp result is given.
[0194] In a step S6 a control signal is provided that can be used for displaying the classification
result and/or controlling the crimp device by utilizing the control signal by the
control unit, e.g. especially based on a crimp quality control signal associated with
determined crimp height.
[0195] Although specific embodiments have been illustrated and described herein, it will
be appreciated by those of ordinary skill in the art that a variety of alternate and/or
equivalent implementations exist. It should be appreciated that the exemplary embodiment
or exemplary embodiments are only examples, and are not intended to limit the scope,
applicability, or configuration in any way. Rather, the foregoing summary and detailed
description will provide those skilled in the art with a convenient road map for implementing
at least one exemplary embodiment, it being understood that various changes may be
made in the function and arrangement of elements described in an exemplary embodiment
without departing from the scope as set forth in the appended claims and their legal
equivalents. Generally, this application is intended to cover any adaptations or variations
of the specific embodiments discussed herein.
List of reference signs
[0196]
- 100
- crimp device
- 110
- crimping tool
- 111
- crimping tool front end
- 112
- crimp press
- 120
- crimp anvil
- 121
- crimp anvil support
- 200
- sensor for detection of a time-based structure-borne sound signal, first
- 201
- sensor for detection of a time-based structure-borne sound signal, second
- 210
- sensor for detection of a time-based force signal
- 220
- sensor for detection of a time-based position signal
- 221
- position reference element of the crimping tool
- 230
- sensor for detection of a time-based elongation signal
- 240
- sensor for detection of a time-based temperature signal
- 250
- sensor for detection of a time-based acceleration signal
- 300
- support frame
- 400
- machine readable program code
- 500
- control unit
- SBS1
- time-based structure-borne sound signal, first
- SBS2
- time-based structure-borne sound signal, second
- F
- time-based force signal
- P
- time-based position signal
- E
- time-based elongation signal
- T
- time-based temperature signal
- PT
- Trigger position
- To
- Starting time for detection period
- delta t
- detection period
- C
- conductor
- CE
- crimp element
- t
- time
- AR
- moving direction of the crimping tool relative to the crimp anvil caused by the crimp
press
- S0
- Detection and Provision of a plurality of time-based signals
- S1
- Examination of thresholds of sensor and machine data
- S2
- Detection on severe anomalies
- S3
- Detection of light anomalies
- S3`
- Detection of presence of conductor
- S4
- Assessment of crimp height adjustment
- S4'
- Assessment of crimp height
- S4"
- Assessment of completeness of strands
- S4‴
- Assessment of position of conductor
- S5
- Determination of classification result
- S6
- Provision of classification results as control signal
1. Method for crimping a crimp element (CE) to a conductor (C) by a crimp device (100)
comprising a crimping tool (110) and a crimp anvil (120),
- whereas at least one time-based signal (SBS1, SBS2, F, P, E, T) is detected (S0)
relating to the crimping process performed by the crimp device (100),
- whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) is analysed
(S3, S3', S4, S4', S4", S4‴) by applying the at least one time-based signal (SBS1,
SBS2, F, P, E, T) to a trained neural network, whereas the trained neural network
is configured to classify a result of a crimping process based on the received at
least one time-based signal (SBS1, SBS2, F, P, E, T),
- whereas a classification result comprising at least a class corresponding to a non-defective
crimp result and a class corresponding to a defective crimp result is provided (S5),
especially by the trained neural network, based on the classification performed by
the trained neural network,
- whereas a control signal is generated and provided as output based on the determined
classification result (S6).
2. Method according to claim 1,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based force signal (F) related to the force applied to a crimp element (CE)
by the crimping tool (110), whereas the at least one time-based force signal (F) is
detected for a defined time period (delta t) comprising a contact phase of the crimping
tool (110) and the crimp element (120).
3. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based structure-borne sound signal (SBS1, SBS2) detected at the crimping
tool (110) and/or at the crimp anvil (120) and/or at the crimp anvil support (121),
whereas the at least one time-based signal of structure-borne sound (SBS1, SBS2) is
detected during a relative movement of the crimping tool (110) and the crimp anvil
(120) for a defined time period (delta t) comprising a contact phase of the crimping
tool (110) and the crimp element (CE).
4. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based position signal (P) for the crimping tool (110) relative to the crimp
anvil (120), whereas the at least one time-based position signal (P) is detected for
a defined time period (delta t) comprising a contact phase of the crimping tool (110)
and the crimp element (CE).
5. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based acceleration signal (SBS2) detected at the crimping tool (110) and/or
the crimp anvil (120), whereas the at least one time-based acceleration signal (SBS2)
is detected for a defined time-period (delta t) comprising a contact phase of the
crimping tool (110) and the crimp element (CE).
6. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based elongation signal (E) detected at a support frame (300) supporting
the crimping tool (110), whereas the at least one time-based elongation signal (E)
is detected for a defined time-period (delta t) comprising a contact phase of the
crimping tool (110) and the crimp element (CE).
7. Method according to one of the claims 2 to 6,
whereas at least one temperature signal (T) is detected during the crimping process,
especially within and/or for a defined time-period comprising a contact phase (delta
T) of the crimping tool (110) and the crimp element (CE), and provided to the trained
neural network, whereas the trained neural network is configured to consider the at
least one temperature signal (T) for classifying a result of a crimping process based
on the received at least one time-based signal (SBS1, SBS2, F, P, E, T) and the at
least one temperature signal (T).
8. Method according to one of the precedent claims,
whereas the detection of at least one time-based signal (SBS1, SBS2, F, P, E, T) is
triggered by a triggering signal (P) detected by a trigger sensor (220), especially
whereas the trigger signal is generated dependent on a predefined position (PT) of
the crimping tool (110) relative to the crimp anvil (120)
9. Method according to one of the precedent claims,
whereas the control signal is provided with a repetition rate of 2 seconds or less,
especially of 1 second to 0,5 seconds.
10. Method according to one of the precedent claims,
whereas the classification result further comprises a crimp quality indicator, e.g.
the crimp height, which is related to the quality of a crimped connection of the crimp
element (CE) and the conductor (C), especially in case the crimped connection is classified
as non-defective.
11. Method according to one of the precedent claims,
whereas in case a crimped connection of the crimp element (CE) and the conductor (C)
is classified as defective, the classification result further comprises a failure
indicator allowing the identification of a certain defect from a plurality of defects
identifiable by the trained neural network for the crimped connection of the crimp
element (CE) and the conductor (C).
12. Method according to one of the precedent claims,
whereas in case a crimped connection of the crimp element (CE) and the conductor (C)
is classified as defective the classification result further comprises a data anomaly
indicator in case no identification of a certain defect from a plurality of defects
identifiable by the trained neural network for the crimped connection of the crimp
element (CE) and the conductor (C) can be determined.
13. Method according to one of the precedent claims
whereas the crimp device (100) is controlled based on the control signal in such way
that the crimping process, especially at least one control parameter of the crimp
device 100, is changed such that a non-defective crimp connection comprising a crimp
element (CE) and a conductor (C) to be processed by the crimp device (100) is created.
14. Machine readable program code (400) comprising control commands, which initiate in
case of their execution a method according one of the preceding claims.
15. Control unit (500) comprising machine readable program code (400) comprising control
commands, which initiate in case of their execution a method according one of the
preceding method claims.
16. Crimp device (100) comprising a crimping tool (110) and a crimp anvil (120), further
comprising at least one sensor (201, 201, 210, 220, 230, 240) to detect at least one
time-based signal (SBS1, SBS2, F, P, E, T) during a crimping process, further comprising
a control unit according to claim 15 connected to the at least one sensor (SBS1, SBS2,
F, P, E, T).
Amended claims in accordance with Rule 137(2) EPC.
1. Method for crimping a crimp element (CE) to a conductor (C) by a crimp device (100)
comprising a crimping tool (110) and a crimp anvil (120),
- whereas at least one time-based signal (SBS1, SBS2, F, P, E, T) is detected (S0)
relating to the crimping process performed by the crimp device (100),
- whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) is analysed
(S3, S3', S4, S4', S4", S4‴) by applying the at least one time-based signal (SBS1,
SBS2, F, P, E, T) to a trained neural network, whereas the trained neural network
is configured to classify a result of a crimping process based on the received at
least one time-based signal (SBS1, SBS2, F, P, E, T),
- whereas a classification result comprising at least a class corresponding to a non-defective
crimp result and a class corresponding to a defective crimp result is provided (S5),
especially by the trained neural network, based on the classification performed by
the trained neural network, - whereas the classification result is configured as output
vector comprising information regarding the kind of a determined defect,
- whereas a control signal is generated and provided as output based on the determined
classification result (S6).
2. Method according to claim 1,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based force signal (F) related to the force applied to a crimp element (CE)
by the crimping tool (110), whereas the at least one time-based force signal (F) is
detected for a defined time period (delta t) comprising a contact phase of the crimping
tool (110) and the crimp element (120).
3. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based structure-borne sound signal (SBS1, SBS2) detected at the crimping
tool (110) and/or at the crimp anvil (120) and/or at the crimp anvil support (121),
whereas the at least one time-based signal of structure-borne sound (SBS1, SBS2) is
detected during a relative movement of the crimping tool (110) and the crimp anvil
(120) for a defined time period (delta t) comprising a contact phase of the crimping
tool (110) and the crimp element (CE).
4. Method according to one of the claims 2 or 3,
whereas at least one temperature signal (T) is detected during the crimping process,
especially within and/or for a defined time-period comprising a contact phase (delta
T) of the crimping tool (110) and the crimp element (CE), and provided to the trained
neural network, whereas the trained neural network is configured to consider the at
least one temperature signal (T) for classifying a result of a crimping process based
on the received at least one time-based signal (SBS1, SBS2, F, P, E, T) and the at
least one temperature signal (T).
5. Method for crimping a crimp element (CE) to a conductor (C) by a crimp device (100)
comprising a crimping tool (110) and a crimp anvil (120),
- whereas at least one time-based signal (SBS1, SBS2, F, P, E, T) is detected (S0)
relating to the crimping process performed by the crimp device (100),
- whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises
- at least one time-based force signal (F) related to the force applied to a crimp
element (CE) by the crimping tool (110), whereas the at least one time-based force
signal (F) is detected for a defined time period (delta t) comprising a contact phase
of the crimping tool (110) and the crimp element (120) and/or
- at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least one time-based
structure-borne sound signal (SBS1, SBS2) detected at the crimping tool (110) and/or
at the crimp anvil (120) and/or at the crimp anvil support (121), whereas the at least
one time-based signal of structure-borne sound (SBS1, SBS2) is detected during a relative
movement of the crimping tool (110) and the crimp anvil (120) for a defined time period
(delta t) comprising a contact phase of the crimping tool (110) and the crimp element
(CE), and
- additionally at least one temperature signal (T) detected during the crimping process,
especially within and/or for a defined time-period comprising a contact phase (delta
T) of the crimping tool (110) and the crimp element (CE), and provided to the trained
neural network, whereas the trained neural network is configured to consider the at
least one temperature signal (T) for classifying a result of a crimping process based
on the received at least one time-based signal (SBS1, SBS2, F, P, E, T) and the at
least one temperature signal (T),
- whereas the at least one time-based temperature signal (T) and the at least one
time-based force signal (F) or the at least one time-based temperature signal (T)
and the at least one time-based signal of structure-borne sound (SBS1, SBS2) or the
at least one time-based temperature signal (T) and the at least one time-based force
signal (F) and the at least one time-based signal of structure-borne sound (SBS1,
SBS2) are analysed (S3, S3', S4, S4', S4", S4‴) by applying these to a trained neural
network, whereas the trained neural network is configured to classify a result of
a crimping process based on the received at least one time-based signals (SBS1, SBS2,
F, P, E, T),
- whereas a classification result comprising at least a class corresponding to a non-defective
crimp result and a class corresponding to a defective crimp result is provided (S5),
especially by the trained neural network, based on the classification performed by
the trained neural network,
- whereas a control signal is generated and provided as output based on the determined
classification result (S6).
6. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based position signal (P) for the crimping tool (110) relative to the crimp
anvil (120), whereas the at least one time-based position signal (P) is detected for
a defined time period (delta t) comprising a contact phase of the crimping tool (110)
and the crimp element (CE).
7. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based acceleration signal (SBS2) detected at the crimping tool (110) and/or
the crimp anvil (120), whereas the at least one time-based acceleration signal (SBS2)
is detected for a defined time-period (delta t) comprising a contact phase of the
crimping tool (110) and the crimp element (CE).
8. Method according to one of the precedent claims,
whereas the at least one time-based signal (SBS1, SBS2, F, P, E, T) comprises at least
one time-based elongation signal (E) detected at a support frame (300) supporting
the crimping tool (110), whereas the at least one time-based elongation signal (E)
is detected for a defined time-period (delta t) comprising a contact phase of the
crimping tool (110) and the crimp element (CE).
9. Method according to one of the precedent claims,
whereas the detection of at least one time-based signal (SBS1, SBS2, F, P, E, T) is
triggered by a triggering signal (P) detected by a trigger sensor (220), especially
whereas the trigger signal is generated dependent on a predefined position (PT) of
the crimping tool (110) relative to the crimp anvil (120)
10. Method according to one of the precedent claims,
whereas the control signal is provided with a repetition rate of 2 seconds or less,
especially of 1 second to 0,5 seconds.
11. Method according to one of the precedent claims,
whereas the classification result further comprises a crimp quality indicator, e.g.
the crimp height, which is related to the quality of a crimped connection of the crimp
element (CE) and the conductor (C), especially in case the crimped connection is classified
as non-defective.
12. Method according to one of the precedent claims,
whereas in case a crimped connection of the crimp element (CE) and the conductor (C)
is classified as defective, the classification result further comprises a failure
indicator allowing the identification of a certain defect from a plurality of defects
identifiable by the trained neural network for the crimped connection of the crimp
element (CE) and the conductor (C).
13. Method according to one of the precedent claims,
whereas in case a crimped connection of the crimp element (CE) and the conductor (C)
is classified as defective the classification result further comprises a data anomaly
indicator in case no identification of a certain defect from a plurality of defects
identifiable by the trained neural network for the crimped connection of the crimp
element (CE) and the conductor (C) can be determined.
14. Method according to one of the precedent claims
whereas the crimp device (100) is controlled based on the control signal in such way
that the crimping process, especially at least one control parameter of the crimp
device (100), is changed such that a non-defective crimp connection comprising a crimp
element (CE) and a conductor (C) to be processed by the crimp device (100) is created.
15. Machine readable program code (400) comprising control commands, which initiate in
case of their execution the execution of a method according one of the preceding claims.
16. Control unit (500) comprising machine readable program code (400) comprising control
commands, which initiate in case of their execution the execution of a method according
one of the preceding method claims.
17. Crimp device (100) comprising a crimping tool (110) and a crimp anvil (120), further
comprising at least one sensor (201, 201, 210, 220, 230, 240) to detect at least one
time-based signal (SBS1, SBS2, F, P, E, T) during a crimping process, further comprising
a control unit according to claim 16 connected to the at least one sensor (SBS1, SBS2,
F, P, E, T).