BACKGROUND OF THE INVENTION
Technical Field
[0001] The invention relates to a device for recognizing characteristic features of an empty
container having at least one planar support element on which the empty container
can be placed on a contact surface of the support element with a lateral surface of
said container, having a carrier to carry the empty container and having at least
one optical sensor to detect at least one characteristic feature of an empty container
and having a transport/sorting apparatus that removes and sorts the empty containers
following detection of the at least one feature.
[0002] The invention further relates to a method for recognizing characteristic features
of an empty container, wherein a lateral surface of the empty container is scanned
by means of an optical sensor and wherein the empty container is guided during the
scanning with a lateral surface on a supporting element while rotating about its longitudinal
axis.
Discussion
[0003] Standard automated reverse vending machines have an input module to accept empty
containers, for example bottles and/or beverage cans. The empty container inserted
is transported to an identification module by a transport module. The empty container
is rotated in the identification module with the aid of additional drives so that
any identifying features applied to the empty container, e.g. barcode, deposit symbol
and/or other special features, can be ascertained by means of an optical sensor. At
least one sensor, for instance a barcode reader and/or a camera, is mounted on the
device to determine the identifying features. Several sensors can be provided for
determining different features. The empty container is taken to a sorting module from
the identification module by a further transport module. In the sorting module, the
empty container is taken to one of several possible conveyor elements that guide the
empty to collecting stations, depending on the identifying features determined by
the sensors. Optional provision can be made in addition for the empty containers to
be fed to a compacting module to reduce volume. Devices of this type are also described
as crushers.
[0004] An input module and a transport module for a reverse vending system are known from
DE 101 44 518C1. The input module has a drop channel formed from two curved rods via which the empty
container inserted through an input opening in an outer wall of the reverse vending
machine is taken to the transport module located below the input opening. At the end
of the drop channel facing the transport module, the input module has guide means
that ensure that the empty container is placed in a standing position on the adjacent
transport module. The transport module is configured in essence as a horizontally
oriented endless conveyor belt.
[0005] An identification module for reverse vending machines is known from
DE 10 2008 018 796 A1 in which empty containers conveyed in a standing position on a transport belt are
scanned by an optical sensor. For this purpose, a stationary plate-shaped support
element is provided above the transport belt that is aligned perpendicular to the
section of the transport belt receiving the empty container and forms an acute angle
to the direction of transportation. The standing empty containers being conveyed on
the transport belt bear against the stationary plate as they are being transported.
Because of the frictional force created between the plate and the empty container,
the container is set rotating in the direction of transportation as it is being carried
on the transport belt. The optical sensor is located and aligned in such a manner
that it scans the empty container during its rotation at the plate and thus the complete
circumference of the lateral surface of the empty container is detected. In this way
it can be ensured that the barcode, the deposit symbol and/or any other characteristic
feature of the empty container can be identified reliably regardless of its original
position relative to the optical sensor.
[0006] A device for sorting empty containers that are taken to the device by way of a transport
module is known from
DE 101 17 451 A1. The sorting device has a drive shaft extending essentially parallel to the transport
direction of the empty containers above an endless conveyor belt of the transport
module. Sorting arms fixed against rotation are connected to the drive shaft that
encompass spaced apart on both sides an empty container entering the effective area
of the sorting device. By driving the drive shaft in one direction or the other, the
sorting arms convey the empty container to one side or the other of the transport
belt. The empty container can thus be directed to one of two specified conveyor elements.
If more than two conveyor elements are to be implemented, several sorting devices
can be arranged one after the other.
[0007] The disadvantage of the solutions known from the prior art is that the input, transport,
identification and sorting functions are realized by means of separate functional
modules. The functional modules represent separate structural units that are arranged
one after the other and are linked to each other by means of information technology.
As a result of this restriction, current reverse vending machines for empty containers
are relatively large. Furthermore, because of the multiplicity of functional modules,
they are expensive to manufacture and maintain and are relatively prone to breakdowns.
SUMMARY OF THE INVENTION
[0008] It is, therefore, the object of the present invention to provide an especially simple,
compactly constructed and cost-effective device and a simplified method for returning
empty containers.
[0009] To achieve this object, an embodiment of the invention is characterized in that the
carrier is formed by the at least one support element and in that the at least one
support element is carried to be rotatable about an essentially horizontal drive shaft
in such manner that the empty container can be brought from an input position, in
which the empty container can be placed on the at least one support element, into
at least one transfer position from which the empty container can be passed on to
a downstream functional module.
[0010] An advantage of the invention is that the support element supports the empty container
and simultaneously acts as carrier for the empty container. A separate transport module
to carry and transport the empty container is not necessary.
[0011] The input module, the identification module and the transport module connecting the
input module and the identification module are preferably implemented as one functional
and structural unit. As a result, the size of the reverse vending machine is reduced.
Secondly, the entire device can be operated using a single drive so that substantial
cost benefits result. In addition, the risk of malfunctions and breakdowns diminishes
since the number of components is reduced, and the data link for separate functional
modules for input, transport and identification of the empty container can be dispensed
with.
[0012] In accordance with a preferred embodiment of the invention, the empty container is
carried so that it can roll on the support element with its lateral surface and be
scanned by the optical sensor as it rotates about its longitudinal axis. As an advantageous
consequence, the lateral surface of the empty container can be detected around its
entire circumference by the optical sensor. The characteristic features of the empty
container, its geometry, the nature of its surface and its visual material properties
can be read just like a barcode and/or a deposit symbol regardless of the orientation
of the empty container when it is inserted. The rotation of the empty container about
its longitudinal axis can take place without providing an additional drive simply
on the basis of the rotational movement of the support element, against which the
empty container is guided with its lateral surface so that it can roll, around the
drive shaft.
[0013] If the characteristic feature is not recognized during a rotation of the support
elements in one direction, the support elements can be rotated in the opposite direction.
[0014] In accordance with a further development of the invention, the longitudinal axis
of the empty container in the input position and/or in the transfer position is oriented
parallel to the drive shaft. As a result of the parallel positioning of the longitudinal
axis and the drive shaft, the empty container rolls over its lateral surface as the
support elements rotate about the drive shaft. This prevents the empty container from
slipping or sliding along the support elements. The drive shaft of the support elements
can be oriented in the direction of the user at an angle between 0 and 180 degrees.
The preferred orientation of the drive shaft is dependent on the downstream sorting
paths, the construction and the positioning of the motor.
[0015] In accordance with a further development of the invention, the support element carrying
the empty container is located at an acute angle rotated downward in the input position
and/or the transfer position. The acute angle is greater than 0° and less than 45°.
Preferably the acute angle is greater than 0° and less than 15°. The empty container,
in its input position and/or the transfer position, is advantageously brought into
a defined stationary position as a result of the force of weight acting thereon. The
stationary position can be brought about mechanically, for example, by a support element
itself and by a fixed retaining element. Inserting the empty container is simplified
to the extent that the customer does not have to position the empty container precisely.
Instead, the empty container assumes its stationary position by itself. Transferring
the empty container to a downstream functional module is also simplified since the
position of the empty container is known exactly after it has been identified by the
optical sensor. Since the empty container is brought into the input position and/or
the transfer position solely due to the effect of weight, a separate drive is also
not necessary so that the construction of the device can be further simplified and
costs reduced.
[0016] In accordance with a further advantageous embodiment of the invention, the empty
container in the input position and/or the transfer position can be brought into a
defined stationary position as a result of the force of weight acting on it through
a special geometry and alignment of the support element even without a fixed retaining
element.
[0017] In accordance with a further advantageous embodiment of the invention, the support
arms of the support element in the input position to receive an empty container are
aligned symmetrically to a vertical plane running through the drive shaft. This embodiment
possesses the same advantages as the embodiment previously described. The design,
however, is considerably simplified by the symmetrical construction.
[0018] The support elements can have different geometries.
[0019] In accordance with a further development of the invention, the support element has
a planar and/or curved and/or angled shape, at least in sections. A planar support
element is advantageous if the empty container is to roll on the support element at
a predetermined rotational speed and brought from the input position into the transfer
position. A planar support element is additionally simple and cost-effective to produce.
[0020] A curved and/or angled support element provides the advantage that the empty container
in the input position and/or in the transfer position and/or when bringing said container
from the input position into the transfer position can be immobilized at specified
locations on the support element. This geometry offers at least one possible stationary
position in the input position and/or transfer position without requiring additional
components.
[0021] An angled support element makes it possible to tip an empty container that is not
round in cross-section, but rectangular for example, through the rotation of the support
element about its longitudinal axis and to detect an initially concealed part of the
surface not detectable by the optical sensor.
[0022] In accordance with a further development of the invention, the support element has
at least two structurally identical support arms disposed offset around the drive
shaft. The support arms project radially from the drive shaft. A support angle of
180° or less is included between adjacent support arms. For example, three structurally
identical support arms can be preferably arranged offset to each other around the
drive shaft at the same support angle. The three support arms can have the identical
radial length. The support element is advantageously given the form of a rotor. For
each rotation of the rotor, a number of empty containers corresponding to the number
of support arms can be placed in the device, scanned in said device and moved into
the transfer position. This increases the throughput of the device. In addition, the
support arms form an angled support element with the advantages described.
[0023] The dimensions of the support elements are advantageously selected such that as the
empty container rotates about its longitudinal axis its entire lateral surface can
be scanned using at least one, preferably fixed, optical sensor.
[0024] In accordance with a further development of the invention, the empty container, after
being optically scanned, can be taken to a specified functional module, for example
for collection, compacting, further transportation, return or additional processing.
Depending on the specified functional module, the support element is rotated about
the drive shaft clockwise or counter-clockwise at an individually selectable speed
of rotation. When determining the direction of rotation and the speed of rotation
of the support element, the location of the functional module in particular and the
size and weight of the empty containers must be taken into account. The sorting function
is thereby advantageously integrated into the inventive device. As a result, provision
of a separate sorting module can be dispensed with, as can a second transport module
connecting the sorting module and the identification module. This measure benefits
the compact size of the device. By dispensing with additional drives, guides or the
like, the cost and the proneness of the device to break down are similarly reduced.
In accordance with a further development of the invention, the dimensions of the support
arms of the support element are selected such that the empty container can be scanned
around its entire circumference as the empty container rolls on the contact surface
of the support element.
[0025] In accordance with a further development of the invention, two optical sensors located
offset to each other are provided. As a result, the area of the surface of an empty
container detected by the sensors is increased. The rolling of the empty container
for detecting the lateral surface, in particular the characteristic features on the
lateral surface, can thus take place in a smaller area. Empty containers lying or
rolling on the support elements are optically scanned from different directions by
the two sensors. In addition, the two sensors can be aligned with their optical axes
in such a way that at least a first sensor detects the empty containers specifically
in the input position and at least one second sensor detects the empty containers
as they roll on the support elements and/or in the transfer position. The angle of
rotation of the empty container for complete detection of the lateral surface is advantageously
reduced compared with a previous solution by the size of the angle between the optical
axes of the sensors. Since the angle of rotation is proportional to the distance covered
by the empty container as it rolls, the radial length of the support arms, or the
dimensions of the support element, are simultaneously reduced.
[0026] In accordance with a further development of the invention, the device is equipped
with a reflector unit which reflects light in the direction of the at least one sensor.
Without the reflector unit, this light would not reach the sensor. The reflector unit
thus contributes to the sensor not only detecting light reflected directly from the
surface of an empty container towards the sensor, but also light reflected outside
an acceptance angle of the sensor centered around the optical axis of the sensor.
Thus the sensor can detect, for example, not only the surface of an empty container
facing it, but also the areas aligned laterally. The reflector unit makes it possible
to use only a single sensor. The reflector unit is mounted in such a way in the detection
zone or the measurement beam of the at least one optical sensor that the detection
zone can be divided into partial detection zones or the measurement beam can be divided
into partial measurement beams and such that the empty container can be scanned by
at least two detection zones or measurement beams offset by a measurement angle with
individual acceptance angles. Preferably the at least one optical sensor and the reflector
unit can be positioned in such a way that the detection zone or the measurement beam
and/or the partial detection zones or partial measurement beams from the sensor are
disposed symmetrically with respect to a plane running vertically through the drive
shaft. The reflector unit can have a first reflector located symmetrically with respect
to this plane with two reflector segments located at an angle to each other that divide
the detection zone emanating from the sensor or divide the measurement beam into two
partial detection zones or partial measurement beams. The reflector unit can further
have two second reflectors located spaced apart and symmetrical to the center plane
and the drive shaft to reflect the two partial detection zones or partial measurement
beams generated at the first reflector towards the support elements. As a result,
an empty container can advantageously be located in two different detection zones
or be scanned optically from two different directions using a single sensor. This
reduces the angle of rotation of the empty container for complete detection of the
lateral surface by the size of the angle between the two directions of observation
or partial measurement beams. Since the angle of rotation is proportional to the distance
covered by the empty container as it rolls, the radial length of the support elements,
or the dimensions of the support elements, are simultaneously reduced as a result.
[0027] The dimensions of the support elements can be further reduced if there is no requirement
for scanning the entire surface or if there is a requirement for the user to align
the empty container, for example in the way that the empty container is to be placed
with the barcode facing up in the direction of the sensor. It is also possible to
reduce the dimensions of the support element if the empty container does not have
a barcode but only recognition of the shape is undertaken. In this case, the empty
container is not rotated at all on account of its rotational symmetry. The dimensions
of the support element can consequently be reduced to the diameter of the empty container.
[0028] In accordance with a further development of the invention, a distance for the at
least one optical sensor from the drive shaft is selected such that the measurement
beam in the area of the drive shaft has a scanning field width perpendicular to the
center plane that is at least twice as large as the radial length of the at least
one support arm. The empty container can advantageously be detected by a single, preferably
fixed, optical sensor as it rotates about its longitudinal axis. As long as the scanning
field width of the optical sensor corresponds to twice the radial length of the support
arm and the empty container is supported in the input position at an open end of a
first support arm and in the transfer position at an open end of the second support
arm, the support element has the necessary minimum diameter for complete detection
of the empty container. The empty container is detected by the optical sensor in the
input position and the transfer position.
[0029] In accordance with a further development of the invention, the position of the empty
container, or the position of the support element, is continuously analyzed during
the movement for identification or sorting. If all necessary features have been detected,
the rotary motion, depending on the downstream sorting process, is continued for sorting,
if necessary with a correction of rotational speed, or immediately discontinued. In
this case, at least one change of direction is required for continued movement for
sorting. This sequence considerably increases the throughput of the device.
[0030] In accordance with a further development of the invention, the support element can
be rotated back and forth or tilted in order to detect the features of the empty container.
This is particularly advantageous in a device in which the stationary position is
ensured by the geometry of the support element in the input and/or transfer position.
The scanning field of the sensor extends to both sides of the axis of the stationary
position. If the features cannot be detected as the support element is rotated in
one direction, the direction of rotation can be changed. This rolls the empty container
into the other part of the scanning field relative to the axis of the stationary position
and the previously concealed part of the surface is scanned.
[0031] The invention can be further characterized as a method where the empty container,
as the result of a rotation of the support element about an essentially horizontal
drive shaft, moves by itself from an input position in which the empty container is
placed on the at least one support element into one or more transfer positions in
which the empty container is delivered to a downstream functional module.
[0032] A particular advantage of the invention is that the rotation of the empty container
around its longitudinal axis takes place automatically, that is without additional
drives, solely on the basis of the force of weight acting on the empty container.
As a result of rotation, a different partial area of the lateral surface of the empty
container constantly moves into the detection zone of the optical sensor. As a result,
partial areas of the surface of the empty container that were initially concealed
in the input position and not detected by the optical sensor are optically detected
as said container rolls from the input position into the transfer position. A barcode
or a deposit symbol is consequently detected by the optical sensor during rotation
along the support element regardless of the original orientation of the empty container
in the input position. The detection process is considerably simplified by dispensing
with separate drives.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Embodiments of the invention are explained in greater detail using the Figures.
Figures 1a - 1d show a schematic drawing of a device to recognize empty containers
in a first embodiment,
Figures 2a - 2b show a second embodiment of the invention,
Figures 3a - 3e show a schematic drawing for the detection of empty containers that
are rectangular in cross-section by means of the device in accordance with Figures
2a and 2b.
Figure 4 shows a third embodiment of the device,
Figure 5 shows a schematic drawing of the device with sorting function in a first
embodiment,
Figure 6 shows a schematic drawing of the device with sorting function in a second
embodiment,
Figure 7 shows a schematic drawing of the device with sorting function in a third
embodiment,
Figure 8 shows a fourth embodiment of the device,
Figure 9 shows a fifth embodiment of the device,
Figure 10 shows a sixth embodiment of the device.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] A device 1 for recognizing characteristic features of an empty container 2 that is
circular in cross-section in accordance with Figures 1 a to 1 d consists essentially
of a support element 4 carried rotatably on a drive shaft 3 and an optical sensor
5 located at a radial distance from the drive shaft 3. A measurement beam 6 emanating
from the optical sensor 5 serves to detect the empty container 2 lying against the
support element 4 by means of a measurement beam 6 expanding from the optical sensor
5 towards the support element 4.
[0035] The device 1 is used, for example, in reverse vending machines that are set up by
the retail trade to allow customers to automatically return empty containers 2 having
a radius r. In reverse vending machines of this type, after the the empty containers
2 are inserted by the customer, they first have to be taken to an identification unit.
A determination is made in this identification unit whether it is a returnable empty
container 2, for example a non-returnable or returnable bottle or can with a deposit,
and the deposit to be paid to the customer upon the return of the empty container.
After the empty container 2 has been detected in the identification module, the empty
container 2 can be taken in a downstream sorting module to one of several transport
elements and/or reduced in volume in a compacter, for example crushed or shredded.
As a result of the automation process, the process of returning empties is particularly
efficient and the sales staff is relieved of a significant burden.
[0036] The support element 4 is constructed in the shape of a rotor and possesses three
essentially structurally identical support arms 7.1, 7.2, 7.3. The support arms 7.1,
7.2, 7.3 extend radially from the drive shaft 3 and have the same radial length I
so that the open ends 8.1, 8.2, 8.3 of the support arms 7.1, 7.2, 7.3 lie on a common
circular path 9 oriented coaxially to the drive shaft 3. The support arms 7.1, 7.2,
7.3 are disposed offset at an identical support angle y of 120°. A V-shaped trough
10 is formed between two adjacent support arms 7.1, 7.2, 7.3. The support arms 7.1,
7.2, 7.3 have in addition a planar contact surface 11 in the radial direction to guide
the empty container 2. To this extent, the support element 4 forms planar contact
surfaces 11 in the area of the support arms 7.1, 7.2, 7.3. The support element 4 is
configured angled down in the area of the V-shaped troughs 10.
[0037] The optical sensor 5 is configured, as an example, as an image-transmitting sensor
(camera) or as a laser scanner. The optical sensor 5, together with the essentially
horizontally oriented drive shaft 3 of the support element 4, defines a center plane
M of the device 1. The measurement beam 6 of the optical sensor 5 is configured symmetrically
with respect to this center plane M. The measurement beam 6 of the optical sensor
5 spreads out starting from the optical sensor 5 in the direction of the support element
4. At the level of the drive shaft 3, the measurement beam 6 has a scanning field
width w perpendicular to the center plane M that is twice as large as the radial length
I of the support arms 7.1, 7.2, 7.3. As free design parameters for selecting the scanning
field width w, firstly the distance a of the optical sensor 5 from the drive shaft,
secondly an acceptance angle δ of the measurement beam 6 are available. It generally
holds that with a smaller acceptance angle δ, the distance a from sensor 5 to drive
shaft 3 has to be increased. With an increasing acceptance angle δ, the distance a
can be reduced. Typical acceptance angles δ of commercial optical sensors lie in the
range between 0° and 120°, for example 30° or 60°.
[0038] The method for ascertaining the characteristic features of the empty container 2
is as follows: The empty container 2 is placed in a basic position of the device 1
in accordance with Figure 1 with an lateral surface 12 of said container on the contact
surface 11 of a first support arm 7.1, 7.2, 7.3 of the support element 4 facing the
optical sensor 5. The support element 4 is positioned so that the first support arm
7.1 is located rotated down at an acute angle α from the horizontal. Acute angle α
is greater than 0° and smaller than 45°. Preferably acute angle α is greater than
0° and smaller than 15°. The empty container 2 can be placed manually by a customer
at any position on first support arm 7.1 through a recess in a housing of the device
1, which is not shown. Because of the force of weight (gravity) acting on the empty
container 2, the empty container 2 is moved automatically in the direction of the
open end 8.1 of the first support arm 7.1 until the empty container 2 is stopped stationary
in an input position (first stationary position) against a first fixed retaining element
13.1 of the reverse vending machine. The lateral surface 12 of the empty container
2 is lying on the contact surface 11 of the first support arm 7.1 facing the optical
sensor 5 and against the first fixed retaining element 13.1. A longitudinal axis 14
of the empty container 2 is arranged oriented parallel to the drive shaft 3.
[0039] After the empty container 2 has been inserted, the support element 4 is rotated counter-clockwise
around the drive shaft 3 by a drive (not shown). As soon as the first support arm
7.1 - as shown in Figure 1a - passes the horizontal, the empty container 2 moves automatically
and while rotating about its longitudinal axis 14 from the open end 8.1 of the first
support element 7.1 in the direction of the drive shaft 3. In accordance with Figure
1c, the empty container 2 reaches the V-shaped trough 10 between the first support
arm 7.1 and a second support arm 7.2 at a time when both the first support arm 7.1
and the second support arm 7.2 are positioned above the drive shaft 3. Support element
4 is rotated further in a counter-clockwise direction until the second support arm
7.2 in accordance with Figure 1d is positioned below the drive shaft 3 and includes
an acute angle β with the horizontal. The acute angle β is greater than 0° and smaller
than 45°, preferably greater than 0° and smaller than 15°. Acute angle α and acute
angle β can be chosen to be equal.
[0040] As soon as second support arm 7.2 passes the horizontal, the empty container 2 moves
out of the V-shaped trough 10 in the direction of the open end 8.2 of second support
arm 7.2. As it does so, it rotates about its longitudinal axis 14 and reaches a transfer
position (second stationary position) as soon as it is lying with its lateral surface
12 against the second, similarly fixed retaining element 13.2. To bring the empty
container 2 from the input position into the transfer position, support element 4
is required to rotate through less than 90°. From the transfer position, the empty
container 2 can be taken to a downstream functional module (not shown), for example,
a transport module having at least one conveyor element 27 or a compacter or at least
one collection bin 23, 24,25, 26. (see, Figures 5-7)
[0041] The rotational speed of the empty container 2 about its longitudinal axis 14 matches
the angular velocity of support element 4 rotating about drive shaft 3 for as long
as the empty container 2 is immobile against the open ends 8.1, 8.2 of support arms
7.1, 7.2 or in the V-shaped trough 10 and there is no relative motion with respect
to support element 4. As soon as the empty container 2 rolls on the support arms 7.1,
7.2 of support element 4, the rotation of the empty container 2 about its longitudinal
axis 14 is added to the rotary motion of support element 4 about the drive shaft 3.
Consequently, the rotational speed of the empty container 2 is greater than the angular
velocity of support element 4.
[0042] The support element 4 has a dual function when an empty container 2 is detected.
First, it acts as a support surface on which the empty container 2 lies while rotating
about its longitudinal axis 14. In addition, the support element 4 carries the empty
container 2 so that a separate carrier, for example a transport belt is not required.
[0043] If the scanning field width w of the measurement beam 6 corresponds to at least twice
the length I of the support arms 7.1, 7.2, 7.3, the empty container 2 is detected
by the optical sensor 5 regardless of its position on support element 4. The radial
length I of the support arms 7.1, 7.2, 7.3 can be selected such that the surface 12
of the empty container 2 is detected by the optical sensor 5 around its full circumference.
The minimum required radial length of the support arm 7.1, 7.2, 7.3 is defined by
the ratio of the product of Pi (Π) to the maximum radius r of the largest empty container
2 accepted and to the angular rotation required to detect the complete circumference
of the lateral surface 12 of the empty container 2 on the one hand, and to 360° on
the other. This ensures that the characteristic features of the empty container 2,
for instance, its external shape, its surface quality and/or its visual material properties
as well as a barcode or deposit symbol applied to the surface of the empty container
2 can be detected using the optical sensor 5 regardless of the orientation of the
empty container when inserted by the customer.
[0044] In accordance with an alternative embodiment of the device 1 as shown in Figures
2a and 2b, the empty container 2 being carried on the support element 4 can be scanned
by two optical sensors 5, 15. The optical sensors 5, 15 are located symmetrically
with regard to the center plane M on both sides of said plane. The optical sensors
5, 15 and the partial measurement beams 16.1, 16.2 emanating from the sensors 5, 15
are located offset by a measurement angle ε. The measurement angle ε is greater than
0° and smaller than 180°, preferably greater than 20° and smaller than 150°, and in
a particularly preferred embodiment greater than 60° and smaller than 120°.
[0045] Identical components and component functions are given identical reference numerals.
[0046] In a known way, the empty container 2 is brought along first support arm 7.1 and
second support arm 7.2 from the input position to the transfer position as said container
rotates about its longitudinal axis. The lateral surface 12 of the empty container
2 is detected in the area of the open end 8.1 of first support arm 7.1 by partial
measurement beam 16.1 of first optical sensor 5 and in the area of the open end 8.2
of second support arm 7.2 by partial measurement beam 16.2 of second optical sensor
15. In the area of the V-shaped trough 10 between first support arm 7.1 and second
support arm 7.2 the surface 12 of the empty container 2 is detected by the two partial
measurement beams 16.1, 16.2 of optical sensors 5, 15.
[0047] By providing two optical sensors 5, 15, the empty container 2 can be scanned particularly
advantageously and in a simple manner by the two partial measurement beams 16.1, 16.2.
In comparison to the single-sensor solution, a greater part of the surface 12 can
be registered because of the measurement angle ε between the sensors 5, 15 without
any rotation. As a result, the angle of rotation of the empty container 2 needed for
complete detection of the lateral surface 12 is reduced by the measurement angle ε
between the two partial measurement beams 16.1, 16.2. Since the angle of rotation
is proportional to the distance covered by the empty container 2 rolling on support
element 4, the radial length I of support arms 7.1, 7.2, 7.3, or the dimensions of
support element 4, are reduced at the same time.
[0048] The dual-sensor embodiment of Figures 2a and 2b offers a further advantage in the
detection of non-rolling empty containers 17, which are quadratic in cross-section,
for example. In accordance with Figures 3a to 3e, in which only the support arms 7.1
and 7.2 necessary for operation are illustrated, the empty container 17, which is
square in cross-section, slides from the input position in the direction of the V-shaped
trough 10 between first support arm 7.1 and second support arm 7.2 placing a first
lateral face 18 against the contact surface 11 of the first support arm 7.1. In the
input position from Figure 3a, a second lateral face 18.2 of the empty container 17
can be scanned by first sensor 5 alone. With increasing rotation of the support element
in the counter-clockwise direction in accordance with Figure 3b, a third lateral face
18.3 of the empty container 17 is rotated into partial measurement beam 16.1 of first
sensor 5 such that a third lateral face of the empty container 17 can be scanned by
first sensor 5.
[0049] With continuing rotation of support element 4, the empty container 17 reaches the
V-shaped trough 10 (Figure 3c) and tilts in the direction of second support arm 7.2
as a result of the force of weight acting upon it as soon a center of gravity of the
empty container 17 passes the center plane M (Figure 3d). As a result of the empty
container 17 sliding in the direction of the V-shaped trough 10 and said container
tilting in the direction of second support arm 7.2, a fourth lateral face 18.4 of
the empty container 17 comes into the effective range of partial measurement beam
16.2 of second sensor 15.
[0050] As soon as second support arm 7.2 has rotated beyond the horizontal and is below
the drive shaft 3, the empty container 17, placing its second lateral face 18.2 against
the contact surface 11 of the second support arm 7.2, slides from the V-shaped trough
10 towards the open end 8.2 of second support arm 7.2. At the latest when reaching
the transfer position according to Figure 3e, first lateral face 18.1, which initially
lay against contact surface 11 of first support arm 7.1 and could not be detected
optically, comes into the detection zone of second partial measurement beam 18.2 of
second optical sensor 15.
[0051] An alternative embodiment of the invention as shown in Figure 4 provides for a reflector
unit 19 to be mounted in the partial measurement beam 6 of optical sensor 5. The reflector
unit 19 consists of a first reflector 20 and two second reflectors 21.1, 21.2. First
reflector 20 is located like sensor 5 in the center plane M and is made up of two
reflector segments 20.1, 20.2 arranged angled towards one another. The angled reflector
segments 20.1, 20.2 of first reflector 20 serve to divide the measurement beam 6 emanating
from optical sensor 5 into two partial measurement beams 22.1, 22.2 which, like the
original measurement beam 6, spread out symmetrically with respect to center plane
M. The two partial measurement beams 22.1, 22.2 strike the second reflectors 21.1,
21.2 and are reflected from there towards support element 4. The partial measurement
beams 22.1, 22.2 include the measurement angle ε'. Second reflectors 21.1, 21.2 are
located in such a way between the sensor and the support element and laterally spaced
apart from the center plane M that at least first partial measurement beam 22.1 scans
the empty container 2 in the input position and at least second partial measurement
beam 22.2 scans the empty container 2 in the transfer position.
[0052] With respect to the advantages and the reduction of the dimension of support element
4, the reflector solution in accordance with Figure 4 corresponds to the dual-sensor
solution in accordance with Figures 2a and 2b. Since, however, only one sensor 5 is
provided that is located in the center plane M, the dimensions of the device 1 can
be further reduced compared with the dual-sensor solution. For example, it has been
possible to reduce a width b to less than 300 mm and a height t to less than 600 mm
by using the reflector solution.
[0053] Compared with the embodiment of the invention of Figure 1, the radial length of support
arms 7.1, 7.2, 7.3 in the dual-sensor solution from Figures 2a and 2b and the reflector
solution from Figure 4 can be reduced by the ratio of the product of Pi to the measurement
angle ε, ε' and the radial length I on the one hand, and 360° on the other. For example,
the length I of support arms 7.1, 7.2, 7.3 at the measurement angle ε, ε' of 120°
is reduced by one third and at the measurement angle ε, ε' of 60° by one sixth.
[0054] In accordance with a further embodiment of the invention as shown in Figure 5, the
device 1 can implement a sorting function. Depending on the direction of rotation
and the rotational speed of support element 4, the empty container 2 is taken from
the transfer position to the specified collection bin 23, there is a total number
of four collection bins 23, 24, 25, 26. If support element 4 is rotated slowly from
the transfer position in a counter-clockwise direction around the drive shaft 3, the
empty container 2 goes to the first collection bin 23. With a fast rotational movement
of support element 4 in a counter-clockwise direction, second support arm 7.2 acting
as a carrier for the empty container 2 is rotated away under the empty container 2
so that the empty container 2 is no longer carried by support element 4 and falls
into the second collection bin 24 as a result of the force of weight acting on said
container. As long as support element 4 is rotated in a clockwise direction and second
support arm 7.2 passes the horizontal, the empty container 2 rolls from the open end
8.2 of second support arm 7.2 towards the V-shaped trough 10 and is finally stopped
there. If support element 4 is rotated further slowly in a clockwise direction, the
empty container 2 goes to the third collection bin 25, which can be configured, for
example, as a return tray for non-returnable empty containers 2 and can be located
facing the customer. If support element 4 is rotated quickly in a clockwise direction
instead after reaching the V-shaped trough 10, the empty container 2 goes into the
fourth collection bin 26.
[0055] Figure 6 shows a further possibility of implementing the sorting function. After
reaching the transfer position, support element 4, of which only support arm 7.2 relevant
to operation is drawn in here, is initially rotated in a clockwise direction. The
empty container rolls from the open end 8.2 of support arm 7.2 towards the V-shaped
trough 10 and is retained here. Then support element 4 is rotated counter-clockwise
such that the empty container 2, depending on the rotational speed of support element
4 and the final angular position of said element, is taken to a predetermined collection
bin, one of the three bins 23, 24, 25 located on a common side of center plane M.
As an option, the weight and size of the empty container 2 can be determined and used
to set the rotational speed.
[0056] Instead of providing collection bins 23, 24, 25, 26, the scanned empty container
2 can be taken to a conveyor element 27 represented by a conveyor belt, a conveyor
slide or similar, in accordance with Figure 7. As an alternative, of course, a different
number of conveyor elements 27 and/or collection bins 23, 24, 25, 26 can be provided.
Similarly, collection bins 23, 24, 25, 26 and conveyor elements 27 can be combined
in a common array.
[0057] In accordance with an alternative embodiment of the invention shown in Figure 8,
the input position can be assumed in the V-shaped trough 10 instead of at an open
edge 8.1 of first support arm 7.1. The empty container 2 is positioned in the device
1 by the customer in such a way that its barcode and/or deposit symbol is turned towards
optical sensor 28. Optical sensor 28 is designed so that it detects the part of the
lateral surface 12 of the empty container 2 with a small scanning field. After the
empty container 2 has been scanned, support element 4 is rotated counter-clockwise
in a known way. The empty container 2 detaches itself from the V-shaped trough 10
as soon as second support arm 7.2 has passed the horizontal and is located below the
drive shaft 3. The container moves while rotating about its longitudinal axis towards
the open end 8.2 of second support arm 7.2 and reaches the transfer position in a
known way. In this alternative embodiment, a particularly cost-effective optical sensor
28 with a limited scanning field width w can be used advantageously. Because of the
high integration density and the small number of components, particularly the drives,
the already cost-effective device 1 can be further reduced in terms of cost by the
low-priced sensor 28. Since no rotation of the bottle is required, the support elements
and thus all the equipment can be dimensionally smaller.
[0058] In accordance with a further alternative embodiment of the invention as shown in
Figure 9, support element 4 is configured completely planar. In contrast to the previous
embodiments of Figures 1 to 8, no V-shaped trough is formed. As support element 4
rotates counter-clockwise, the empty container 2 moves continuously from the input
position into the transfer position. Consequently, the empty container 2 arrives advantageously
in the transfer position with a rotation of a few degrees counter-clockwise of support
element 4. In addition, support element 4 is particularly simply shaped and thus cost-effective
to produce.
[0059] The planar support element 4 can, of course, be combined with the dual-sensor solution
of Figures 2 and 3 and with the reflector solution of Figure 4.
[0060] In accordance with an alternative embodiment of the invention (not shown), the contact
surface 11 of support element 4 can have any contour, in particular have a concave
or convex curvature.
[0061] In accordance with a further alternative embodiment of the invention as shown in
Figure 10, support element 4 is angled. This angled configuration provides a stationary
position between the support arms of the support element. The scanning field of the
sensor spreads out on both sides of the drive shaft and the stationary position, respectively.
The empty container is manually placed by a customer through a recess in a housing
of the device 1 (not shown) at any place on the support element. Because of the force
of weight acting on the empty container, the empty container is retained in the stationary
position in its input position. If the characteristic distinguishing feature is not
recognized by the optical sensor, the support element is rotated first in a clockwise
direction as can be seen in Figure 10a and Figure 10b. The empty container rolls down
one support arm of the support element. If the radial length I of the support arm
or the width of the scanning field of the sensor positioned on the right next to the
drive shaft is not sufficient to detect the features, the support element is rotated
back counter-clockwise past the input position (Figure 10c and Figure 10d) until the
characteristic feature has been detected.
[0062] All features of the invention can be essential to the invention both individually
and in any combination with each other.
List of reference numerals
[0064]
- 1
- Device
- 2
- Empty container
- 3
- Drive shaft
- 4
- Support element
- 5
- Optical sensor
- 6
- Measurement beam
- 7.1, 7.2, 7.3
- Support arms
- 8.1, 8.2, 8.3
- Open ends
- 9
- Circular path
- 10
- V-shaped trough
- 11
- Contact surface
- 12
- Lateral surface
- 13.1, 13.2
- 1st/2nd retaining elements
- 14
- Longitudinal axis
- 15
- Optical sensor
- 16.1, 16.2
- Partial measurement beam
- 17
- Rectangular empty container
- 18.1, 18.2, 18.3, 18.4
- Lateral face
- 19
- Reflector unit
- 20
- First reflector
- 20.1, 20.2
- Reflector segments
- 21.1, 21.2
- Second reflector
- 22.1, 22.2
- Partial measurement beam
- 23
- First collection bin
- 24
- Second collection bin
- 25
- Third collection bin
- 26
- Fourth collection bin
- 27
- Conveyor element
- 28
- Optical sensor
- a
- Distance
- b
- Width
- I
- Radial length
- r
- Radius
- t
- Height
- w
- Scanning field width
- M
- Center plane
- α, β
- Acute angle
- δ
- Acceptance angle
- Y
- Support angle
- ε, ε'
- Measurement angle
1. A device for recognizing characteristic features of an empty container having at least
one flat support element on which the empty container can be placed with a lateral
surface of said container on a contact surface of the support element, having a carrier
to carry the empty container and having at least one optical sensor for optically
scanning the empty container, comprising wherein the carrier is formed by the at least
one support element (4) and that the at least one support element (4) is carried rotatable
about an essentially horizontal drive shaft (3) in such a way that the empty container
(2, 17) can be brought from an input position in which the empty container (2, 17)
can be placed on the at least one support element (4) to another location on the support
element, and after being scanned can be transferred to a downstream functional module
(23, 24, 25, 26, 27).
2. The device of claim 1, wherein the drive shaft of the support element is oriented
to the user at an angle between 0 and 180 degrees.
3. The device of claim 1, wherein the empty container (2, 17) is guided so that it can
roll with its lateral surface on the support element (4) and can be scanned by the
optical sensor while rotating about its longitudinal axis (14).
4. The device of claim 1, wherein a longitudinal axis (14) of the empty container (2,
17) in the input position and/or in the transfer position is located oriented parallel
to the drive shaft (3).
5. The device of claim 1, wherein the support element (4) carrying the empty container
(2, 17) is aligned in the input position and/or in the transfer position in such a
way that its support arms form at least one stationary position that the empty container
(2, 17) can assume as a result of the force of its weight acting thereon.
6. The device of claim 1, wherein the contact surface (11) of the support element (4)
is configured at least in sections planar and/or curved and/or angled.
7. The device of claim 1, wherein the support element (4) has at least two structurally
identical support arms (7.1, 7.2, 7.3) disposed offset at an angle around the drive
shaft (3), where the support arms (7.1, 7.2, 7.3) project radially from the drive
shaft (3) and where a support angle (Y) of less than or equal to 180° is included
between adjacent support arms (7.1, 7.2, 7.3).
8. The device of claim 1, wherein at least three structurally identical support arms
(7.1, 7.2, 7.3) are located offset to each other at the same support angle (Y) around
the drive shaft (3) and wherein the support arms (7.1, 7.2, 7.3) have an identical
radial length (I).
9. The device of claim 1, wherein the empty container (2, 17) is supported in the input
position by means of a fixed first retaining element (13.1) at one open end (8.1)
of the first support arm (7.1) and/or in the transfer position by way of a fixed second
retaining element (13.2) at an open end (8.2) of the second support arm (7.2).
10. The device of claim 1, wherein the empty container (2, 17), after being scanned and
depending on the rotational direction of the support element (4) and the rotational
speed of said support element, can be taken to a specified functional module (23,
24, 25, 26, 27).
11. The device of claim 1, wherein the position of the support element (4) is continuously
analyzed during the movement for scanning or sorting to optimize the further movement
for sorting.
12. The device of claim 1, wherein the dimensions of the support arms (7.1, 7.2, 7.3)
of the support element (4) are selected such that the empty container (2, 17) can
be scanned around its complete circumference as said container rolls on the contact
surface (11) of the support element (4).
13. The device of claim 1, wherein the lateral surface (12) of the empty container (2,
17) is optically scanned from different directions by two or more sensors (5, 15).
14. The device of claim 1, wherein the lateral surface (12) of the empty container (2,
17) is optically scanned by one sensor (5) with the aid of a reflector unit (19).
15. The device of claim 1 in a reverse vending machine for the automated return of empty
containers (2, 17).
16. A method for ascertaining characteristic features of an empty container, wherein a
lateral surface of the empty container is scanned by means of at least one optical
sensor and wherein the empty container is guided on a support element while rotating
about its longitudinal axis, comprising wherein the empty container (2, 17), as the
result of a rotation of the support element (4) about an essentially horizontal drive
shaft (3), is transferred automatically from an input position in which the empty
container (2) is placed on the at least one support element (4), and after being scanned,
is transferred to a downstream functional module (23, 24, 25, 26, 27).
17. The method of claim 17, wherein the rolling of the empty container (2, 17) during
the scanning of the lateral surface to ascertain the characteristic feature is subject
to a change of direction.