Note: Descriptions are shown in the official language in which they were submitted.
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ANIMAL CARCASS ACTIVE CUT SYSTEM AND METHOD
FIELD OF THE INVENTION
The present invention relates to a system and a method
for cutting parts of an animal carcass, like the primary cuts
of an animal carcass, and more particularly to a system
having a cutting tool actively positioned, at any time and at
will, with a joystick or a similar manual control, and
optionally with a concurrent or alternate automated control,
and a method thereof.
BACKGROUND
In the meat products industry, the animals (e. g. bovine,
ovine, hog) are generally transformed in two principal
stages, namely the slaughtering and the cutting of the
carcasses.
In the slaughtering process, the animals are killed and
then usually hanged vertically by the hind legs onto wheeled
hooks running along a horizontal rail mounted at the ceiling.
The vertically laid carcasses are thereby carried and passed
through various working stations such as for the evisceration
and the longitudinal separation at the middle of the
backbone. Once separated, there are in fact two half-
carcasses that are hanged with the hooks. Once the operations
related to the slaughtering process are completed, the half-
carcasses are sent to refrigeration rooms for cooling
purposes.
When leaving the refrigeration rooms, the half-carcasses
are still vertically hanged on the wheeled hooks and are
carried toward the primary cut department, where they are
unhooked and laid down on a horizontal conveyor which is a
part of what is called the main break-up table in the
slaughtering industry. The half-carcasses are positioned in
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such a way that the fore and hind legs are directed toward
the conveyor sides, and such that the inner part of the
carcass is upward and the outer part (with the skin) is
downward. The half-carcasses are thereby laid horizontally
and transversely on the conveyor. On each side of the
conveyor, saws sever the legs, the hindquarter and the
shoulder as the carcasses move forward on the conveyor. The
parts thereby severed are swerved towards other conveyors
that carry them to their next respective transformation
stages. The flank (belly) and loin, forming the center or
middle part of the half-carcasses goes on another horizontal
conveyor which is a part of what is called the middle table
in the slaughtering industry, in order to be turned
longitudinally with the conveyor and passed to another saw
for separating the loin from the flank, or separating only
the back ribs from the flank ribs keeping the loin and the
flank attached toward the next step where the loin is pulled
and separated from the flank. In this type of operation
(American method), a circular scribe saw is used in place of
a band saw. Other conveyors then carry the loins and the
flanks to their next respective transformation stages.
Thus, each half-carcass is separated in parts like legs,
hindquarter, shoulders, loins, flanks. This corresponds to
the most widely used organization for the primary cut of
carcasses in high production plants. However, this layout
requires a lot of difficult and laborious handlings from the
operators. Indeed, as the cutting is performed when the meat
parts move through the saw, they must nevertheless be aligned
so that they pass in the saw at the proper location. The
operator must then move entire half-carcasses on the running
conveyor to position them at the proper location with respect
to the position of the saw.
Known in the art is US patent no. 4,557,014 (Vogt)
showing an example of an automated system for cutting
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carcasses by means of an arrangement of three successive cut
stations through which the carcasses pass while being hanged
vertically to a single and same conveyor. Each cut station
comprises a cutting tool whose position is set as a function
of the cutting points identified with the assistance of a
vision system.
Also known in the art is US patent no. 4,662,029
(Helsene et al.) showing an example of an automated system
for cutting carcasses carried on by a conveyor provided with
side-installed cutting tools. An optical scanner produces an
image of the carcasses, and a computer controls the
positioning of the cutting tools as a function of a
comparison of the carcass image with a programmed cutting
conf igurat ion .
The carcass primary cut systems known in the art are
unable to achieve cuts following paths other than a straight
line during the cutting operation, i.e. from the moment the
cutting tool engages the animal carcass up to when the
cutting operation is finished, which represents potentially
considerable losses for the industry since the different
parts of a carcass do not have the same market value and a
straight cut in the parts is often not the most profitable
one. It would therefore be highly desirable to be capable of
changing the cutting path instantaneously at will during the
cutting operation. Furthermore, a failure of one of the
equipment like an electronic board or a sensor in automated
cut systems may be the cause of costly breakdowns, during
which the workers must rely again on traditional arduous
manual carcass positioning methods to prevent the
interruption of the whole production line.
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SUMMARY
An object of the invention is to provide an animal
carcass active cut system which does not involve the
difficult and arduous operation of manually positioning the
animal carcasses on the conveyor, while being adapted for
complete automation of the cutting process.
A subsidiary object of the invention is to provide an
animal carcass active cut system capable of doing specific
cut profiles, i.e. wherein the cutting tool is controllably
moveable at any time and at will so that the cutting may
follow any desired cutting path, thereby increasing the
efficiency and the accuracy of the cutting operation in
accordance with the standards of cutting.
Another subsidiary object of the invention is to provide
such an active cut system that can be used in bovine, ovine,
hog and other types of slaughter and butcher applications,
and which requires no or almost no direct manual force
intervention from the operator.
Another subsidiary object of the invention is to provide
such an active cut system, which can process left and right
carcasses on the same line.
Another subsidiary object of the invention is to provide
such an active cut system, which may be used as a part of
main and middle tables in carcass processing plants.
Another subsidiary object of the invention is to provide
such an active cut system, which may be used as a back-up
alternative or an overriding control unit for automated cut
systems.
Another subsidiary object of the invention is to provide
such an active cut system in which the cutting path is
adaptive to the morphology of the piece of meat, the system
being configurable to the customer's specifications.
According to the present invention, there is provided an
animal carcass active cut system, comprising:
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a conveyor for transporting animal carcasses from front
to rear sections thereof;
a mobile cutting tool positioned between the front and
rear sections, and adapted to successively cut the carcasses
transported by the conveyor;
motion means for moving, at any time, the cutting tool
along a transversal course relative to the conveyor, in
response to a drive signal;
a manual control producing a motion control signal in
response to a user action indicating a displacement of the
cutting tool in a desired direction across the course; and
motion control circuit means for driving the motion
means by generating the drive signal as a function of the
motion control signal.
Preferably, the manual control is formed of a joystick
that generates the motion control signal as a function of a
thrust on the joystick with respect to a central position.
According to the present invention, there is also
provided an animal carcass active cut method, comprising the
steps of:
transporting animal carcasses along a course passing by
a cutting tool operatively positioned to successively cut the
carcasses; and
actively displacing the cutting tool transversely to the
course using a manual control in operative control of a
transverse position of the cutting tool relative to the
course, the manual control being responsive to a user action
indicating a displacement of the cutting tool in a desired
direction across the course.
BRIEF DESCRIPTION OF THE DRAWINGS
A detailed description of preferred embodiments will be
given herein below with reference to the following drawings:
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Figure 1 is a perspective view of a main table provided
with animal carcass active cut systems according to the
present invention;
Figure 2 is a perspective view of a middle table
provided with animal carcass active cut systems according to
the present invention;
Figure 3 is a functional block diagram of a control
circuit of an animal carcass active cut system according to
the present invention;
Figure 4 is a functional block diagram of a detector/
sensor block in the control circuit shown in Figure 3;
Figure 5 is a functional block diagram of a vision block
in the control circuit shown in Figure 3; and
Figure 6 is a schematic diagram of a motion block in the
control circuit shown in Figure 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to Figures 1 and 2, there are shown possible
embodiments of active cut systems according to the invention
in relation with a main table (Figure 1) and a middle table
(Figure 2) for primary cuts of animal carcasses like left and
right hog carcasses 1,2 in the Figures.
The system has a conveyor 3 onto which the half
carcasses 1,2 are transversely laid down (automatically or
manually) at a front section thereof. The conveyor 3
transports the half-carcasses 1,2 from the front section to
the rear section thereof. The conveyor 3 may be of a
multiple-belt type if desired, as illustrated. Mobile cutting
tools like band saws 4A-E having moving courses
perpendicularly to the conveyor 3 are provided along the
conveyor 3 (e.g. with their blade extending between two
adjacent belts) at positions determined by the parts of the
half-carcasses 1,2 to be cut during their displacement from
the front to the rear sections of the conveyor 3. Scribe saws
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or other types of cutting tools can be used depending on the
needs.
Referring to Figure 1, the conveyor 3 carries the half-
carcasses 1,2 horizontally and transversely. The orientation
of the half-carcasses 1,2 mainly depends on the nature of the
cut to be done and will vary accordingly. The half-carcasses
1,2 on the conveyor 3 pass by a first cut system provided
with a band saw 4A for cutting the hind foot of each half-
carcass 1,2. The band saw 4A can be mounted on guides or
rails like the rails 14C of the saw 4C, extending on a side
of the conveyor 3, guiding the band saw 4A along a
transversal course relative to the conveyor 3. An electric,
hydraulic or pneumatic actuator 5A or any suitable motion
device is operatively associated with the band saw 4A to
position it along the course, at any time. It should be noted
that a circular saw or any other cutting tool capable to
perform the desired cut can be equally used instead of the
illustrated band saw 4A.
Depending on the position and the morphology of each
half-carcass 1, 2 on the conveyor 3, the saw 4A will have to
be displaced to adjust from one piece to the next. The
displacement of the saw 4A can be controlled by an operator
who, by means of a joystick 8A or any other suitable manual
control like buttons, switches, etc., analog or digital,
actively controls the displacement direction and optionally
the displacement speed of the saw 4A to perform the cutting
along the best cutting path. A light beam produced for
example by a laser 7A may be used to show the position of the
blade of the saw 4A in order to guide the operator during the
displacement of the saw 4A.
The displacement of the saw 4A can also be automated as
it will be described hereinafter.
The half-carcasses 1,2 (now short of the hind foots)
keep on moving on the conveyor 3 towards the hindquarter cut
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system provided with the saw 4B and the shoulder cut system
provided with the saw 4C. These systems are similar to the
hind foot cut system described above. The saws 4B-C can be
inserted between the side and central belts of the conveyor
3. Motorized rollers 13B-C or motorized cylindrical brushes,
attached to the saws 4B-C may be used to fill in the opening
between the belts during displacements of the saws 4B-C, if
desired. Spiked chains 12 projecting between the belts can be
used for stabilization of the half-carcasses 1,2 during the
cutting operations.
Referring to Figure 2, the half-carcasses 1,2 (now
further short of the hind quarters and the shoulders so being
formed of the remaining bellies) keep on moving on the same
conveyor 3 or are transferred on another conveyor 3 adapted
to further process them.
A pick and place system 15 or an operator rotates the
bellies 37 in order to lay them longitudinally in the
direction of their displacement. Opposite cutting systems
similar to those described above can be installed for left
and right bellies, or the bellies can be all cut at the same
cutting system. A runner guide 16 and pusher 17 arrangement
or any other suitable alignment system may be provided to
align properly the bellies. For this kind of pieces, each saw
4D-E is preferably 15° slanted from the vertical as depicted
by the arrow 20, to provide a more profitable cut at the
level of the flank. Other angles can be selected by suitable
adjustments if desired. Each saw 4D-E can be inserted between
the side and center belts of the conveyor 3.
Referring to Figure 3, there is shown a functional block
diagram of a control circuit for the system according to the
invention. In one of its simplest configuration, the control
of the cutting tool (e.g. saw 4A-E) is performed with the
joystick 8A-E (or other suitable manual control) which
produces a motion control signal in response to a user action
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indicating a displacement of the cutting tool in a desired
direction along the transversal course of the conveyor 3. The
motion control signal is transmitted to a motion block 25
causing the effective displacement of the cutting tool.
Referring to Figure 6, there is shown a functional block
diagram of a possible embodiment of the motion block 25 shown
in Figure 3. A motion controller 31 receives the motion
control signal from the joystick 8A-E (shown in Figure 3),
and generates a drive signal as a function of the motion
control signal, the drive signal driving the actuator 5 which
moves the selected saw 4. Conveyor encoders 10,11 may be used
to provide the motion controller 31 with information on the
current positional state of the conveyor 3. Likewise, a saw
encoder 32 may be used to provide the motion controller 31
with a feedback on the actuator's current position.
Referring back to Figure 3, the control of the cutting
tool can also be automated or semi-automated. In such a case,
a switch 26 can be inserted between the joystick 8A-E and the
motion block 25. The switch 26 has a first input for
receiving the motion control signal from the joystick 8A-E, a
second input for receiving an additional motion control
signal from an automatization circuit, and an output for
selectively transmitting the motion control signals. The
switch 26 may have one of its inputs prevailing on the other,
for example for manual control overriding if desired. The
automatization circuit may take various configurations. It
can be, for example, vision-based or detector/sensor-based or
a combination of both.
The evaluation of the best cutting path and the
positioning of the saws 4A-E can be achieved through a data
acquisition system like the vision block 22 and a data
processor 24 formed for example of a computer 27 with a
screen interface 28 for user interaction and programmation.
Using cutting parameters entered by an operator depending on
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different types of cuts to achieve, the computer 27 can
determine a cutting path to be followed by each saw 4A-E.
Referring to Figure 5 showing an embodiment of the
vision block 22, the operations of evaluating and monitoring
the position and length of the piece of meat 1, 2 during its
passage in the saws 4A-E can be triggered by a photocell 9 ,
and a rotary encoder 10,11 (as shown in Figure 4) may provide
the frame grabber 30 with the position of the piece of meat
1,2. As an alternative, the half-carcasses 1,2 can be evenly
spaced on the conveyor 3, either manually or automatically,
in which case no photocell is needed as the positions of the
half-carcasses 1,2 on the conveyor 3 can be easily determined
if the rotary encoder 10, 11 is adapted for example to cover
exactly one spacing, which means that a zero of the encoder
10,11 corresponds to the beginning of a new processing zone.
The positions can also be determined as a function of the
speed of the conveyor 3 provided that the half-carcasses 1,2
are all laid down on the conveyor 3 at evenly spaced
positions. Other ways of providing the positions of the half-
carcasses 1,2 on the conveyor 3 can be used as well.
The evaluation of the best cutting path and the
positioning of the saws 4A-E is then achieved through a
suitable algorithm running on the computer 27. The algorithm
processes data provided by the data acquisition devices such
as the vision block 22 and/or a detector/sensor block 23
which, as shown in Figure 4, may comprise the conveyor
encoders 10,11, the photocells 9 at various strategic
locations, and even an ultrasonic sensor 19 or any technology
which senses the height (for thickness related data). These
devices can be connected to a programmable logic controller
(P.L.C.) 29 performing a pre-processing of the sensed
information, prior to its transmission to the data processor
24 (shown in Figure 3). The triggering of the data
acquisition operation for example by means of the photocells
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9 causes the system to start to grab information in
conjunction with the rotary encoder 10,11 which monitors the
position and length of the pieces of meat 1,2. The computer
27 can thereby calculate and effect a displacement of the
selected saw 4A-E even while the piece 1, 2 is being cut . So
much that it is possible to follow a cutting profile
according to the requirements of the product or to compensate
for the angle of a half-carcass 1, 2 should it be improperly
positioned.
Thus, whether the displacement of the saws 4A-E is
controlled by an automatic control or by an operator, the
results of the cutting are optimized by the possibility of
following any cutting profile whereas all the cutting systems
heretofore installed on conveyors only provided for straight
line cuts.
Referring to Figures 3-5, to sum up, the semi or fully
automating control of the system fulfils three purposes:
1. Data acquisition, involving the operation of
collecting the information provided by the photocells 9, the
pulse counts of the encoders 10,11, the video signals
provided by the vision block 22 and/or the thickness
information provided by the ultrasonic detector 19, etc.
2. Data processing, involving the operation of deciding
where to perform the cut or determining the cutting path to
be followed as a result of calculations carried out by the
data processor 24 from the collected information.
3. Motion control, involving the operation of
controlling the displacement of the saws 4A-E through the
motion block 25 in order to obtain the physical results
corresponding to the calculations.
The computer 27 may have a control output connected to a
lighting device 21 that can be positioned over the conveyor 3
and may be used in conjunction with the vision block 22 for
the purpose of applying lighting techniques if desired.
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Referring to Figure 5, the vision block 22 (shown in
Figure 3) may be embodied using the photocells 9 producing in
this case triggering information, and a camera/laser 18 or
any suitable camera device, connected to a frame grabber 30
providing image data to the computer 27 (shown in Figure 3).
Referring to Figures 2 and 3, one or several presence
sensors detectors 9 may be used to provide the P.L.C. 29 with
signals corresponding to the thickness or the width of the
piece of meat 1,2 at different points thereof. The P.L.C. 29
then transmits processed data to the computer 27 for further
processing. By combining or by using exclusively the
information received from the vision block 22, the sensors 9
and the encoders 10,11, the computer 27 then determines, in
regards to cutting specifications, the spot where the cut
must be made or alternatively the cutting profile to be
followed and thereby determines the displacements of the
selected saw 4A-E as a function of the speed and displacement
of the conveyor 3. The computer 27 transmits the motion
control signal to the motion block 25.
Referring to Figures 3-6, the frame grabber 30 can be
advantageously embodied by a frame grabber model GENESIS-LC
manufactured by the company MATROX. The camera/laser 18 can
be advantageously embodied by a CCD camera model CV-M30
manufactured by the company JAI, and by an optical lens
manufactured by the company COMPUTAR. An interferential
filter manufactured by the company MELLES GRIOT is placed in
front of the optical lens to filter out the ambient light and
to keep only the reflected laser light. The lighting device
21 can be advantageously embodied by a laser model SNF-501-L
manufactured by the company LASIRIS. The computer 27 can be
advantageously embodied by an industrial computer. The
photocells 9 can be advantageously embodied by cylindrical
photocells #E3F2-R2B4-P1 manufactured by the company OMRON.
The encoders 10, 11 can be advantageously embodied by 320
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pulse incremental encoders #IS581-ABO1R33-0320, and 5000
pulse incremental encoders #IS581-AB01R33-5000 manufactured
by the company INDUSTRIAL ENCODER CORPORATION. The ultrasonic
sensor 19 can be advantageously embodied by an analog
ultrasonic sensor #Q45ULIU64ACRQ manufactured by the company
BANNER. The motion controller 31 can be advantageously
embodied by a motion controller #dmc-1510 manufactured by the
company GALIL MOTION CONTROL INC. The actuators 5 can be
advantageously embodied by electric cylinders #TB32-104B-
24MS2-FC2 manufactured by the company IDC. The manual control
8A-E can be advantageously embodied by a joystick #CSOER
manufactured by the company JR MERRIT.
With the above mentioned components, the joystick 14
will produce a signal varying between t10 V depending on the
right or left position of the joystick's control handle, the
central position providing 0 V. The signal of the joystick 14
is transmitted to the motion controller 31, which drives the
actuator 5. A 10 V signal derived from the joystick 8 will
cause a displacement of the actuator 5 at a maximum speed of
10 inches/s in the direction determined by the sign of the
voltage of the signal produced by the joystick 8, depending
on whether the control handle is pushed on the left or the
right with respect to its central position.
While embodiments of this invention have been
illustrated in the accompanying drawings and described above,
it will be evident to those skilled in the art that changes
and modifications may be made therein without departing from
the essence of this invention. All such modifications or
variations are believed to be within the scope of the
invention as defined by the claims appended hereto.
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