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(11) | EP 3 378 828 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | CONTAINER FILLING MACHINE, HAVING IMPROVED DATA COMMUNICATION AND STORING CAPABILITY |
| (57) A filling machine (1) has: a number of filling units (10) designed to engage at least
one container (2) to carry out filling thereof with a filling product, each filling
unit (10) provided with a respective decentralized control unit (12) configured to
control filling operations thereof; a central control unit (20) to control execution
of the processing operations by the filling units (10); and a digital data communication
bus (16), communicatively coupling the decentralized control units (12) of the filling
units (10) to the central control unit (20), to carry control signals from the central
control unit (20) to the filling units (10) and feedback detection signals from the
filling units (10) to the central control unit (20). The central control unit (20)
is provided with a buffer memory (30), to store, for each filling unit (10) a buffer
(31) of detection data associated to the feedback detection signals during the filling
operations.
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[0001] The present invention relates to a filling machine, designed for filling containers with a product. In particular, the present disclosure relates to a filling unit with improved data communication and storing capability for improved monitoring and analysis with respect to the filling operations being performed.
[0002] In the field of container processing machines, in particular of filling machines for filling containers, like glass bottles, a system is known comprising a feed line for feeding a succession of empty containers to a processing machine, comprising a rotating part, or wheel (so called "carousel"), carrying a number of functional units or stations, arranged on the periphery of the rotating wheel.
[0003] The functional units, in particular filling units, are configured to perform, during the rotation, a desired processing sequence including processing steps, such as: engaging the empty containers; feeding pressurized gas into the containers, if required; filling the containers with the product; decompressing the filled containers, again if required; and then feeding the containers to a capping machine, which is connected to the filling machine by at least one transfer wheel and closes the containers with respective caps.
[0004] Each filling unit includes one or more actuators and feedback sensors. Actuators include e.g. motors, fluidic conduits and flow regulators, including valves that are designed to selectively couple the container to one or more feed devices, or product tanks of the filling machine. Feedback sensors include e.g. pressure sensors, temperature sensors, flowmeters or similar, configured to detect operating values relating to operation of the filling unit.
[0005] Moreover, filling machines are known, wherein filling units are provided with decentralized control units (decentralized controllers) designed to receive control signals from a central control unit to control actuation of the corresponding actuators, and to provide feedback signals to the same central control unit.
[0006] Central control unit (in general a PLC, Programmable Logic Controller, or another suitable digital processing unit), is designed to control general operation of the filling machine according to a desired processing recipe, e.g. providing suitable control signals to the decentralized controllers to cause execution of the desired processing sequence.
[0007] Data communication between the central control unit and the decentralized controllers of the filling units is usually performed through cable wiring.
[0008] A drawback of this solution lies in that the heavy wiring required to connect the plurality of sensors/actuators increases the constructional complexity of the filling machine and decreases the hygiene thereof.
[0009] Another, more recent, solution envisages use of a digital data communication bus, e.g. a fieldbus, for data communication between the central control unit and the decentralized controllers.
[0011] In particular, in order to keep under control the cost of the individual decentralized controllers, a low performance bus using a serial communication protocol (e.g. RS485 at 115,2 bps) is generally implemented.
[0012] This low performance bus does not allow to collect a sufficient amount of data from the feedback sensors allocated on the various filling units, during the processing operations.
[0013] The Applicant has thus realized that known filling machines may suffer from some drawbacks concerning the accuracy and generally the quality and safety of the filling operations.
[0014] Indeed, it may prove difficult to ensure that the correct filling parameters are satisfied during each step of the processing recipe; in this regard, controls and checks performed after the filling process has been completed may not be sufficient to guarantee quality.
[0015] The aim of the present invention is consequently to solve, at least in part, the problem previously highlighted, and in general to provide an improved solution for a filling machine, particularly with respect to control and monitoring of its operation.
[0016] According to the present invention, a filling machine is thus provided, as defined in the appended claims.
[0017] For a better understanding of the present invention, preferred embodiments thereof are now described, purely by way of a non-limiting example, with reference to the attached drawings, wherein:
- Figure 1 is a schematic view of a container processing machine, particularly a filling machine;
- Figure 2 is a schematic block diagram of an electronic control and digital communication system of the filling machine, according to an embodiment of the present solution;
- Figure 3 is a schematic depiction of a buffer memory in the system of Figure 2;
- Figure 4 is an exemplary plot of quantities related to operation of the filling machine; and
- Figure 5 is a schematic block diagram of an electronic control and digital communication system of the filling machine, according to a different embodiment of the present solution.
[0018] Figure 1 schematically shows a processing machine, in particular a filling machine, denoted as a whole with 1, for filling containers 2, for example bottles, with a liquid, such as a food product.
[0019] In a manner that is not shown, filling machine 1 is part of a processing plant (including several machines, e.g. a container blowing machine, the same filling machine 1, a labelling machine, a capping machine and so on, all cooperating in processing of containers), which is provided with a supervising unit (e.g. a PLC or another suitable digital computing apparatus) that supervise and manages operation of the same processing plant.
[0020] Filling machine 1 comprises a conveying device, including a carousel 4, which is mounted to rotate continuously (for example, anticlockwise in Figure 1) about a substantially vertical longitudinal axis A.
[0021] The carousel 4 receives a succession of empty containers 2 from an input wheel 5, which is coupled to carousel 4 at a first transfer station 6 and is mounted to rotate continuously about a respective vertical longitudinal axis B, parallel to axis A.
[0022] The carousel 4 releases a succession of filled containers 2 to an output wheel 8, which is coupled to carousel 4 at a second transfer station 9 and is mounted to rotate continuously about a respective vertical longitudinal axis C, parallel to axes A and B.
[0023] Filling machine 1 comprises a number N of filling stations or units 10, which are equally spaced about axis A, are mounted along a peripheral edge of carousel 4, and are moved by the same carousel 4 along a path P extending about axis A and through transfer stations 6 and 9.
[0024] Each filling unit 10 is designed to receive at least one container 2 to be filled, and to perform, during its rotation along path P, a number of filling operations according to a filling "recipe", in order to fill the container 2 with a fluid (e.g. a carbonated liquid).
[0025] The filling unit 10 is configured to engage the container 2, at an opening of a neck 2' thereof, and includes one or more fluidic conduits, actuators and valves, which are designed to selectively couple the container 2 to one or more feeding devices.
[0026] As schematically shown in Figure 2, according to an aspect of the present solution, each filling unit 10 of filling machine 1 is provided with electronic intelligence, having a respective decentralized control unit (or controller) 12, controlling filling operation performed by the same filling unit 10.
[0027] In particular, the decentralized control unit 12, including a microcontroller or any other suitable digital computing unit, is configured to acquire electrical feedback detection signals from sensor elements 14, e.g. pressure sensors, temperature sensors, flowmeters, or others; the detection signals are related to the processing operations being performed.
[0028] The decentralized control unit 12 is moreover configured to provide electrical control signals to electromechanical actuator elements 15, such as valves, electric motors, pumps or others, in order to control the processing operations being performed.
[0029] According to a particular aspect of the present solution, each decentralized control unit 12 is communicatively coupled to a data communication bus 16, in particular a real-time bus.
[0030] Data communication bus 16 may be an Ethernet-based real-time communication bus, such as the Powerlink bus, Ethercat, Ethernet Realtime, or Profinet, or any other bus capable to offer real-time communication capability (e.g. an optical-fiber based bus). In the context of the present application, real time data communication denotes the possibility to obtain very fast data refresh values, e.g. lower than five milliseconds.
[0031] According to a further aspect of the present solution, data communication bus 16 is coupled to a central control unit 20 of filling machine 1, which, as in the shown embodiment, may be located externally to the carousel 4. In particular, a slip-ring connection element 18 is provided, in order to couple the central control unit 20 to the data communication bus 16.
[0032] The central control unit 20 includes an industrial programmable controller (PLC), or any other suitable digital processing unit, for example a computer running a PLC software application, and represents the central automation core of the filling machine 1, controlling execution of the processing operations by the various filling units 10, according to the desired filling recipe.
[0033] The central control unit 20 may be coupled to a main supervising unit 25, e.g. located remotely with respect to the filling machine 1, via a cabled or remote wireless link 26; main supervising unit 25 may supervise and manage operation of various processing machines in the processing plant, in addition to filling machine 1 (e.g. a container blowing machine, a labelling machine, a capping machine and so on, all cooperating in processing of containers).
[0034] Moreover, the central control unit 20 is operatively coupled to a HMI (Human Machine Interface) unit 28, via a communication link, e.g. including an Ethernet connection.
[0035] HMI unit 28 includes a display device, in order to display data, plots and other information relating to the processing operations being performed, for visualization by a user; HMI unit 28 also includes suitable input devices (not shown), to allow the user to input data and perform actions in the interface.
[0036] According to a particular aspect of the present solution, central control unit 20 is provided with a buffer memory 30, for example of the RAM type; as in the shown embodiment, buffer memory 30 is located internally in the central control unit 20.
[0037] Moreover, a storage database 32 is coupled to the central control unit 20, and may be data-populated by the same central control unit 20 during the filling operations. The storage database 32 may be located internally of, or externally of the control unit 20; e.g. a flash memory, or hard disk, or other data storage means may be provided.
[0038] Storage database 32 may also be accessed by a post-processing computing unit 34, configured to perform post processing operations on the stored data; as shown in the example, post-processing computing unit 34 may access the storage database 32 via an internet connection to cloud storage 35.
[0039] In detail, during operation of the filling machine 1, digital data are continuously transferred in real-time between the central control unit 20 and the decentralized control units 12 via the data communication bus 16, in order to perform the filling operations according to the desired recipe.
[0040] In particular, detection data related to the detection signals acquired by the sensor elements 14 of the respective filling units 10 are communicated by the decentralized control units 12 to the central control unit 20, over the fast data communication bus 16, in real time during the processing operations.
[0041] According to an aspect of the present solution, the central control unit 20 is configured to receive in real time the detection data over the data communication bus 16 and to temporarily store the same detection data in the buffer memory 30; in particular, for each filling unit 10, data relating to a current detection time interval T (for example of 14,4 s) are acquired and stored in the buffer memory 30, each time replacing the data stored for a previous detection time interval.
[0042] In particular, detection data relating to a number n (e.g. equal to 21) of operating parameters relating to the operation of each filling unit 10 are received by the central control unit 20, in real time over the data communication bus 16; the detection data are sampled at a sampling time (e.g. equal to 2,4 ms) and are stored in the buffer memory 30, at each current detection time interval replacing those that had been stored in a previous detection time interval (the most updated sample readings, in the example in a number m equal to 6000, are continuously stored in the buffer memory 30).
[0043] Detection data stored in the buffer memory 30 therefore represent a depiction of the operating state of the filling units 10, in a most recent detection time interval.
[0044] Figure 3 shows a schematic representation of the buffer memory 30, including a data buffer 31 for each filling unit 10, wherein each data buffer 31 stores the detection data relating to the n operating parameters of the respective filling unit 10, acquired during the detection time interval (m samples being acquired during this detection time interval). For example, one of the parameters may be a valve filling pressure for the particular filling unit 10, and the detection data may be the pressure values acquired at each sampling time.
[0045] According to a further aspect of the present solution, data stored in the buffer memory 30 may be transferred into the storage database 32 by the central control unit 20, thus populating the storage database 32.
[0046] In particular, one or more data buffers associated to one or more of the filling units 10 may be transferred into storage database 32.
[0047] Transfer of the stored data may occur, for example, in response to a user command, or a command received from the supervising unit 25, or following generation of an alarm (or occurrence of any other suitable triggering event) in the filling machine 1 (or, generally, in the processing plant), the alarm being indicative of an anomaly or a fault that has been detected (in a per se known manner, here not discussed in detail).
[0048] In particular, the one or more data buffers transferred into the storage database 32 (e.g. for further data analysis and processing) may be associated to the filling unit 10 (or filling units 10) involved in the generation of the alarm (or triggering event).
[0049] Post processing of the data stored in the storage database 32 may advantageously include data comparison between stored detection data relating to operation of different filling units 10, e.g. in order to perform comparative and statistical analysis (in particular, comparison of the detection data relating to a same detection time interval may be performed). For example, the average performance of the filling units 10 may be computed and a deviation from the computed average may be evaluated. Any suitable data analysis or data mining algorithm may also be used.
[0050] In general, the real time data collection allows any suitable diagnostic (descriptive, analytics or predictive) and also auto-tuning of the filling machine 1.
[0051] Moreover, when an alarm is generated (or the triggering event occurs), the HMI unit 28 may be controlled by the central control unit 20 to implement a digital oscilloscope on the display device, i.e. to generate a graphical plot of the detection data stored in the buffer(s) of the one or more filling units 10.
[0052] As previously discussed, these detection data represent the "history" of the filling operations in the detection time interval, spanning up-to and after the alarm or triggering event; this feature thus facilitates trouble shooting and elimination of the cause that generated the alarm.
[0053] Figure 4 shows exemplary plots generated by the above discussed digital oscilloscope implemented by the HMI unit 28, relating to one of the filling units 10 and to exemplary operating parameters, namely the valve flow rate, valve sensor pressure, and the pressure in the product tank acquired during the related detection time interval.
[0054] As shown in Figure 5, a further embodiment of the present solution may envisage the presence of a dedicated control unit 40, operating in parallel to the central control unit 20, coupled to the same data communication bus 16 and configured to acquire and store the detection data.
[0055] Dedicated control unit 40, that may include a PLC or any suitable computing unit (for example a computer running a soft PLC application stored in an associated data storage, e.g. in the form of a Hard Disk), may in this case be configured to store at each filling cycle all data buffers 31 of all filling units 10, to enable full traceability, for each filling unit 10 and each operating parameter. In other words, the whole "film" of the filling operations may thus be stored in storage database 32, for later processing and analysis.
[0056] Dedicated control unit 40 may advantageously be solely dedicated to acquisition and storing of the detection data transferred over the data communication bus 16; the dedicated control unit 40 may also be configured to perform analysis of the acquired detection data.
[0057] In this embodiment, storage database 32 may be populated by the dedicated control unit 40, in addition to, or as an alternative to, the central control unit 20. Moreover, the storage database 32 may be located internally of, or externally of the dedicated control unit 40.
[0058] The advantages that the described solution allows to achieve are clear from the foregoing description.
[0059] In particular, it is again underlined that an improved analysis capability and control on the quality of the filling operations are achieved in the filling machine 1.
[0060] Indeed, the solution enables, for each filling unit 10, capture and buffering of a data history spanning a time up to and beyond an alarm (or triggering event), facilitating troubleshooting, thereby reducing downtime and improving efficiency of the filling machine 1.
[0061] In particular, the provision of a buffer memory 30 storing detection data relating to all the filling units 10 allows to perform combined and comparative analysis, thus further increasing the amount of information that may be used for diagnostic, monitoring and/or predictive analysis.
[0062] Moreover, by adding the dedicated control unit 40 connected to the same real-time digital data communication bus 16, every operating parameters of all filling units 10 may be monitored and stored, to provide complete traceability of each filling cycle thus enabling complete process monitoring and "certification" for the customer of the operations performed.
[0064] Finally it is clear that modifications and variations may be applied to the solution described and shown, without departing from the scope of the appended claims.
1. A filling machine (1), comprising:
a number of filling units (10) designed to engage at least one container (2) to carry out filling thereof with a filling product, each filling unit (10) provided with a respective decentralized control unit (12) configured to control filling operations thereof;
a central control unit (20) configured to control execution of the processing operations by the filling units (10); and
a digital data communication bus (16), communicatively coupling the decentralized control units (12) of the filling units (10) to the central control unit (20), to transfer control signals from the central control unit (20) to the filling units (10) and feedback detection signals from the filling units (10) to the central control unit (20),
wherein the central control unit (20) is provided with a buffer memory (30), configured to store, for each filling unit (10) a data buffer (31) of detection data associated to the feedback detection signals during the filling operations.
2. The filling machine according to claim 1, wherein each data buffer (31) is configured
to store detection data for the respective filling unit (10) during a detection time
interval (T), the detection data in the data buffer (31) being continuously stored
during the filling operations, the detection data of a current detection time interval
being designed to replace in the data buffer (31) the detection data of a previous
detection time interval.
3. The filling machine according to claim 2, wherein the detection data relate to a number
of filling parameters of the respective filling unit (10), and to a number of samples
of the filling parameters in the detection time interval (T).
4. The filling machine according to any of the preceding claims, wherein the digital
data communication bus (16) is a real-time communication bus.
5. The filling machine according to claim 4, wherein the digital data communication bus
(16) is an Ethernet based communication bus.
6. The filling machine according to any of the preceding claims, further comprising a
storage database (32) operatively coupled to the central control unit (20), configured
to receive from the buffer memory (30) a number of the stored data buffers (31) associated
to a respective number of filling units (10) and to store said data buffers for later
analysis and processing.
7. The filling machine according to claim 6, wherein the central control unit (20) is
configured to populate the storage database (32) with the stored data buffers (31)
upon generation of an alarm, or occurrence of a triggering event, relating to the
filling operation being performed.
8. The filling machine according to claim 8, wherein the stored data buffers (31) are
associated to filling units (10) related to the alarm, or triggering event.
9. The filling machine according to any of the preceding claims, further comprising a
Human Machine Interface - HMI - unit (28) operatively coupled to the central control
unit (20), and controlled to display a graphic depiction of the detection data contained
in one or more of the stored data buffers (31).
10. The filling machine according to claim 9, wherein the central control unit (20) is
configured to cause display of the graphic depiction of the detection data contained
in one or more of the stored data buffers (31) upon generation of an alarm, or occurrence
of a triggering event, relating to the filling operation being performed by the respective
filling units (10).
11. The filling machine according to any of the preceding claims, comprising a conveyor
element (4), which is mounted to rotate about a longitudinal axis (A), and carries
the filling units (10) at its periphery, the filling units (10) being designed to
be moved along a path (P) by the rotation of the conveyor element (4); wherein the
decentralized control units (12) are mounted on the conveyor element (4) at the respective
filling units (10), and the central control unit (20) is mounted outside the conveyor
element (4), at a distance therefrom.
12. The filling machine according to claim 11, further comprising a a slip-ring connection
element (18) configured to couple the central control unit (20) to the data communication
bus (16).
13. The filling machine according to any of the preceding claims, wherein each filling
unit (10) is provided with sensor elements (14), configured to generate the feedback
detection signals, and with actuator elements (15) configured to be controlled by
the control signals to perform the filling operations.
14. The filling machine according to any of the preceding claims, further comprising a
dedicated control unit (40), coupled to the data communication bus (16) and configured
to acquire and store the detection data, operating in parallel to the central control
unit (20).
15. The filling machine according to claim 14, wherein each data buffer (31) is configured
to store detection data for the respective filling unit (10) during a detection time
interval (T); and wherein the dedicated control unit (40) is configured to store,
at each detection time interval (T), all data buffers of all filling units (10), for
later processing and analysis to enable full traceability of the filling operations.