Note: Descriptions are shown in the official language in which they were submitted.
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LIVESTOCK HEAD SPLITTING APPARATUS AND OPERATING METHOD OF
SAME
FIELD OF THE INVENTION
The present invention relates generally to an apparatus for splitting the
heads of livestock for organ recovery therefrom, and more particularly to a
rotary
head splitting apparatus simultaneously moving multiple heads through loading,
splitting and discharge stations disposed around the drive shaft of the
apparatus.
BACKGROUND OF THE INVENTION
Different apparatuses have previously been developed for the purpose
of splitting open the heads of livestock animals in order to extract contents
from the
skull, for example the brain or other head organ.
U.S. Patent Numbers 3,105,993 and 4,052,769 teach devices of a type
featuring a vertically reciprocal knife or blade that descends downwardly
toward a
stand on which the head is positioned to effect the splitting operation.
Another type shown in U.S. Patent Number 3,890,673 features a
movable bed or head support means indexed through a head-splitting cabinet
that
features gates that close off the cabinet during the splitting operation.
U.S. Patent Number 4,414,708 teaches another prior art apparatus
using a rotary blade positioned over a conveyer which moves multiple heads
past
the blade on platens that are synchronized to the blade rotation so that the
brain and
pituitary gland are left intact at notches in the blade periphery.
U.S. Patent Number 4,653,145 teaches a rotary head splitter in which
head trays rotatably move around a hydraulically rotated shaft through
loading,
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head-splitting and discharge stations. A vertically reciprocal blade is
respectively
carried over each tray and is hydraulically driven toward the tray as it moves
through
the head-splitting station. Multiple heads are thus moving through the
apparatus at
any given time, each being loaded by an operator at the loading station and
automatically discharged from the machine after splitting.
Applicant has developed an improved rotary head splitter having
unique and advantageous features and operational aspects not shown or
suggested
by the aforementioned prior art.
SUMMARY OF THE INVENTION
According to a first aspect of the invention there is provided a livestock
head splitting apparatus for splitting livestock heads, the apparatus
comprising:
a frame;
a vertical shaft supported on the frame and rotatable about a vertical
longitudinal axis of the shaft;
a plurality of head trays positioned circumferentially about the shaft
and extending horizontally away therefrom, each head tray being connected to
the
shaft for movement about the axis sequentially through loading, head-splitting
and
discharge stations circumferentially spaced around the shaft under rotation of
the
vertical shaft in a predetermined direction;
a plurality of head splitting blades disposed above the head trays in
positions lying respectively thereover and arranged to move with the head
trays
about the axis through the loading, head-splitting and discharge stations
under
rotation of the vertical shaft in the predetermined direction;
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a head splitting actuation system operable in cooperation with the head
trays and the head splitting blades under rotation of the shaft to drive each
head tray
and the respective head splitting blade relatively toward one another from
spaced
apart positions during passage through the head-splitting station and
subsequently
draw the head tray and respective head splitting blade relatively away from
one
another back to the spaced apart positions while approaching the discharge
station;
and
a control system cooperatively linked with the head splitting actuation
system and operable to switch into and out of a head splitting mode of
operation in
which the shaft is driven to carry the head trays through full revolutions
around the
vertical axis and the head splitting actuation system forces together and
draws apart
each head tray and the respective head splitting blade during passage through
the
head splitting station, and a cleaning mode of operation in which the shaft is
driven
to carry the head trays through full revolutions around the vertical axis and
each
head tray and the respective head splitting blade are not driven toward one
another
at any time during said full revolutions around the vertical axis.
Preferably the control system is arranged to remove a source of power
from the actuation system under switching into the cleaning mode and apply
said
source of power to the actuation system under switching into the head
splitting
mode.
Preferably the source of power for the actuation system is provided by
a hydraulic pump for actuating hydraulic actuators of the actuation system,
and a
rotational drive system coupled to the shaft to effect the rotation thereof is
operable
separately from the hydraulic pump.
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Preferably the rotational drive system comprises an electric motor
linked to the shaft to effect the rotation thereof.
Preferably the head splitting actuation system are arranged to effect
lifting of each head tray toward the respective blade in the head splitting
mode of
operation.
Preferably there is provided an enclosure closing around the shaft and
the loading, head-splitting and discharge stations disposed circumferentially
around
the shaft, the enclosure comprising at least one access opening through which
fluid
can be sprayed to clean an interior of the enclosure, whereby operation in the
cleaning mode effects rotation of the head trays past the access opening and
maintains the head trays and the blades in the spaced apart positions
throughout
said rotation to maximize exposure of said trays to sprayed fluid.
Preferably the control system comprises a computerized control
system.
Preferably the control system is arranged to perform confirmation of
successful drawing apart of each head tray and respective head splitting blade
back
to the spaced apart positions, and to stop rotation of the shaft under a lack
of said
confirmation for any tray.
Preferably there is provided a discharge device operable in the head
splitting mode to displace a split head from off each head tray as said head
tray
moves through the discharge station, wherein the control system comprises a
sensor operable to provide confirmation of successful head displacement
operation
of the discharge device for each tray passing through the discharge station in
the
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head splitting mode and is arranged to stop rotation of the electric motor
under a
lack of said confirmation for any tray.
According to a second aspect of the invention there is provided a
method of operating a livestock head splitting apparatus comprising a vertical
shaft
5
rotatable about an axis; a plurality of head trays positioned
circumferentially about
the shaft and extending horizontally away therefrom in connection therewith
for
movement about the axis sequentially through loading, head-splitting and
discharge
stations circumferentially spaced around the shaft under rotation of the
vertical shaft
in a predetermined direction; and a head splitting actuation system operable
to drive
each head tray and a respective splitting blade situated thereabove relatively
toward
one another from spaced apart positions during passage of said head tray
through
the head-splitting station and subsequently draw said head tray and said
respective
head splitting blade relatively away from one another back to the spaced apart
positions while approaching the discharge station; the method comprising:
operating the apparatus in a cleaning mode in which the vertical shaft
is driven for rotation about the axis to convey the head trays sequentially
through the
loading, head-splitting and discharge stations without driving each blade and
the
respective head splitting blade relatively toward one another during passage
through
the head-splitting station; and
during operation of the apparatus in the cleaning mode, directing a
fluid spray toward the head trays rotating about the axis of the vertical
shaft to clean
off surfaces of said head trays with said fluid spray.
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According to a third aspect of the invention there is provided a
livestock head splitting apparatus for splitting livestock heads, the
apparatus
comprising:
a frame;
a vertical shaft supported on the frame and rotatable about a vertical
longitudinal axis of the shaft;
a plurality of head trays positioned circumferentially about the shaft
and extending horizontally away therefrom, each head tray being connected to
the
shaft for movement about the axis sequentially through loading, head-splitting
and
discharge stations circumferentially spaced around the shaft under rotation of
the
vertical shaft in a predetermined direction;
a plurality of head splitting blades disposed above the head trays in
positions lying respectively thereover and arranged to move with the head
trays
about the axis through the loading, head-splitting and discharge stations
under
rotation of the vertical shaft in the predetermined direction;
a head splitting actuation system operable in cooperation with the head
trays and the head splitting blades under rotation of the shaft to drive each
head tray
and the respective head splitting blade relatively toward one another from
spaced
apart positions during passage through the head-splitting station and
subsequently
draw the head tray and respective head splitting blade relatively away from
one
another back to the spaced apart positions while approaching the discharge
station;
an electric motor linked to the shaft to effect the rotation thereof; and
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a computerized control system linked to the motor and comprising an
input device arranged to receive input from an operator for controlling at
least one
operational parameter of said electric motor;
wherein the computerized control system is arranged to receive
separate user inputs for respectively carrying out ongoing rotation of the
shaft for
head splitting operations and incremental rotation of the shaft between such
operations for jogging of the head trays into a desired position around the
axis.
Preferably the computerized control system is arranged to change a
rotational running speed of the motor in response to user run speed input at
the
input device.
Preferably the computerized control system is arranged to change a
rotational jogging speed of the motor in response to user jog speed input at
the input
device.
Preferably there is provided a discharge device operable to displace a
split head from off each head tray as said head tray moves through the
discharge
station, wherein the control system is arranged to change an operational
parameter
of the discharge device according to the change of the rotational running
speed
based on the user run speed input.
Preferably the control system is arranged to change a point in rotation
of the shaft at which the discharge device is actuated.
Preferably there is provided a rotary encoder arranged to monitor
rotation of the shaft.
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Preferably the computerized control system comprises a sensor
operable to provide confirmation of successful displacement operation of the
discharge device for each tray passing through the discharge station, the
computerized control system being arranged to stop rotation of the electric
motor
under a lack of said confirmation for any tray.
Preferably the computerized control system comprises a sensor
operable to provide confirmation of successful drawing apart of each head tray
and
respective head splitting blade back to the spaced apart positions while
approaching
the discharge station, the computerized control system being arranged to stop
rotation of the electric motor under a lack of said confirmation for any tray.
Preferably the computerized control system presents operation mode
input options by which the operator can select to operate the apparatus in a
head
splitting mode in which the head splitting actuation system forces together
and
draws apart each head tray and the respective head splitting blade during
passage
through the head splitting station, and a cleaning mode in which each head
tray and
the respective head splitting blade are not driven toward one another during
rotation
about the axis.
Preferably the computerized control comprises a processor, memory
linked to the processor, and a program stored on the memory, the program
including
program code executable by the processor to display prompts to the operator at
a
display device for input from an input device on the operational parameter of
said
electric motor, to store data reflective of said input, and to use said data
to adjust an
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output signal to be sent to the motor for control of the operational parameter
thereof
during operation of the motor.
Preferably the program includes further program code executable by
the processor to prompt the operator at the display device for an authorized
password, and verify an entered password against the authorized password
before
prompting the operator for the input on the operational parameter of said
electric
motor.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, which illustrate an exemplary
embodiment of the present invention:
Figure 1 is a schematic overhead plan view of a rotary head splitting
apparatus of the present invention.
Figure 2 is a schematic cross-sectional view of the rotary head splitting
apparatus of Figure 1 as taken along line A ¨ A thereof.
Figure 3 is a schematic exploded view of the rotary head splitting
apparatus of Figure 2 with enclosure panels thereof omitted for illustration.
Figure 4 is a schematic isometric view of an assembled frame and
enclosure of the rotary head splitting apparatus.
Figure 5 is a screenshot of a selection screen of a control panel of the
rotary head splitting apparatus.
Figure 6 is a screenshot of a main screen of the control panel of the
rotary head splitting apparatus.
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Figure 7 is a screenshot of a device screen of the control panel of the
rotary head splitting apparatus.
Figure 8 is a screenshot of a setpoint adjustment screen of the control
panel of the rotary head splitting apparatus.
5 Figure
9 is a screenshot of a login screen of the control panel of the
rotary head splitting apparatus.
Figure 10 is a screenshot of an alarm summary screen of the control
panel of the rotary head splitting apparatus.
DETAILED DESCRIPTION
10
Referring now to the drawings, and particularly to Figures 1 to 3, the
head-splitting apparatus of the illustrated embodiment includes a frame 10
rotatably
supporting a vertical shaft 12. Positioned at proximate an upper end of the
shaft are
a plurality of head-splitting units 14, 16, 18 and 20. The head-splitting
units are
rotatably driven through loading, head splitting and discharge stations
situated
circumferentially around the shaft 12. At the loading station, heads are
individually
loaded onto respective trays 22 that lie beneath blades of the head splitting
units.
Rotating around the shaft, each head is then split in the head-splitting
station by
driving of the tray toward the head splitting station, and discharged from the
device
at the discharge station in split condition so that the internal organs may
easily be
removed. A protective enclosure 24 is formed of a number of panels that
cooperate
to close around the stations of the apparatus.
The frame includes four upstanding legs 26 spaced ninety degrees
apart around the axis of the shaft 12 at equal radial distances outward
therefrom,
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and upper and lower reinforcing bars 28 and 30 crossing diagonally at right
angles to
interconnect the upstanding legs 26 to provide a rigid frame or stand for
supporting
the vertical shaft 12 and the head-splitting units. The vertical shaft 12 is
rotatably
received in upper bearing members 32, 34 suitably secured atop and beneath to
the
upper reinforcing bars 28 and a rotating union valve 36 suitably secured to
the lower
reinforcing bars 30.
Between the lower of the two upper bearings 34 near the top of the
shaft 12 and the rotating union valve 36 coupled to the bottom of the shaft, a
square-
in-cross-section hub 38 is carried by the shaft 12 and carries the head-
splitting units
14, 16, 18 and 20. Each head-splitting unit is identical, and while four are
illustrated
in Figure 1, it may be appreciated that the number of units may be varied. For
purposes of simplicity, only one of the head-splitting units is shown in the
exploded
view of Figure 3, to which specific reference and description is now made as
follows.
Each head-splitting unit includes a radially extending lower support
bracket 40 mounting at its outer end a vertically disposed mounting plate 42,
which
in turn carries a vertically oriented double-acting hydraulic cylinder 44
having a
movable piston 46 rod projecting from the top end of the cylinder. Suitably
attached
to the top end of the piston 46, for example by an alignment coupling 48, is a
head
tray holder 50 featuring a horizontally planar base plate 52 atop which a head
tray
22 is seated in turn. At the top end of the mounting plate 42, a block 54 is
carried on
the inner face of this plate in a position over the support bracket 40 and
features a
vertical through bore equipped with bearings 56 that are held in place by a
bearing
retainer 56a. This bore aligns with a respective vertical bore through the
support
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bracket 40 and a guide shaft 58 is slidingly received in these aligned
vertical bores.
The top end of the guide shaft 56 is coupled to the base 52 of the tray holder
50 that
overlies the support bracket 40 in the assembled apparatus. The guide shaft
lies in
the same radial plane of the main rotating shaft 12 as the piston rod 46 of
the
cylinder 44, and thus acts to maintain the assembled head tray holder 50 and
head
tray 22 in a radial orientation relative to the main rotating shaft 12 during
lifting and
lowering of the cylinder piston 46. Such alignment is further maintained by
engagement of a vertical rib 60 jutting radially from the hub 38 over the
respective
support bracket 48 into aligned notches or slots in the tray holder base 52
and the
tray 22 at the ends thereof sitting adjacent the hub 38.
Each head-splitting unit further includes a radially extending upper
support bracket 62 aligned with the lower support bracket 40 at a distance
upward
therefrom. A pair of parallel vertical walls 64 depend a short distance
downward
from the support bracket along the lengthwise dimension thereof (i.e. in the
same
radial direction relative to the main rotational axis 12). The thin slot left
between
these walls 64 is of suitable width to receive therein a knife or blade 66 of
the type
for splitting an animal head of the type for which the device is intended.
Aligned
holes in the in the blade 66 and the blade supporting walls 64 are spaced
along the
upper edge of the blade for receiving fasteners through the aligned holes to
secure
the blade in place for use. As shown in Figure 2, additional support walls 68
may
extend partly down the vertical rib 60 on the opposite sides thereof and
similarly be
equipped with aligned holes for fastening the blade in place at spaced apart
positions along its inner end nearest the hub 38.
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The shaft 12 and head-splitting units are rotatably driven by an electric
gear motor 70 mounted in a housing 72 fixed atop the upper reinforcing bars
28. The
gear motor has an output shaft 74 coupled to the main shaft 12 of the
apparatus, for
example by a pair of coupling hubs 76, 78 engaged together via a spider 80
above a
collar 81 of the main shaft 12. A shaft collar 82 of the gear motor 70 is
equipped
with an industrial rotary encoder 84 to monitor the output shaft's rotation by
measuring the angular position thereof about the shaft's longitudinal axis.
Turning to Figures 1 and 4, arcuate panel sections 86, 88, 90, 92 curve
around the main shaft at a radial distance outwardly past the outer ends of
the head
splitting units 14, 16, 18, 20, and span vertically from the upper
reinforcement 28 to
the lower reinforcement 30, thereby forming the outer protective shield or
cover of an
enclosure containing all the moving parts of the apparatus. At the loading
station, an
access opening 94 is provided for purposes of loading heads onto the trays as
the
head-splitting units pass the loading station. To create this opening, the
panel
section 86 at the loading station may be formed by separate upper and lower
guard
panels 86a, 86b having vertical space between them to form the access opening
94.
The only other opening in the enclosure cover during operation of the machine
is
provided at the discharge station where the split livestock heads
automatically exit
the interior of the enclosure in a manner describe herein further below. This
limited
number of openings to the interior space of the enclosure guards against
inadvertent
contact with the moving splitting units during use of the apparatus.
As In the illustrated embodiment, further access to the interior of the
enclosure for cleaning or service when the machine is not in use can be
achieved by
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swinging opening one or both of two hinged panels 88, 90 on one side of the
machine. In the illustrated embodiment, loading panel section 86 covers the
manual
loading station and spans about ninety degrees around the central shaft of the
machine, discharging panel section 92 covers the automatic discharge station
and
spans about ninety degrees around the shaft from one end of panel section 86,
retracting panel section 90 spans about ninety degrees from the other end of
discharge panel section 92, and extending panel section 88 spans about forty-
five
degrees from the other end of the retracting panel section 90. The
approximately
forty-five degrees remaining between the loading panel section 86 and the
extending
panel section 88 is occupied by a control panel mounting plate 96, as shown in
Figure 4. The extending and retracting panel sections 88, 90 are referred to
as such
because they cover the head splitting station when closed, and more
particularly
respectively cover the sections of the head splitting station where the
cylinder piston
46 of each head splitting unit is extended upward and then retracted downward.
The hydraulic drive for the splitter device of the invention includes a
pump 98 electrically powered by a suitable power pack or source 100. The pump
98
supplies high pressure hydraulic fluid to the stationary input of the rotating
union 36
at the lower reinforcement 30 of the frame, and the output of the rotating
union 36 in
turn provides both high pressure and low pressure lines to the hydraulic
cylinders 44
through hydraulic manifolds 102 that rotate with the shaft and cylinder
control valves
104 that are each carried on the mounting plate of the respective cylinder 44
at a
position therebeneath. A flow control valve 106 is provided between the pump
98
and the rotating union valve 36 for opening and closing high pressure (send)
and low
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pressure (return) hydraulic paths between the pump and the control valves 104
of
the hydraulic cylinders.
The control valve 104 of each head splitting unit is a two-position four-
way cam-operated valve, and thus includes a movable control rod with a cam
5 follower 104a. The control rod is biased to return to a default position
after having
been depressed by a cam and thereafter released. As shown in Figures 1 and 3,
a
horizontal bar or plate 108 arcuately spans ninety degrees about the axis of
the main
shaft 12 between adjacent perpendicular legs of the lower reinforcement 30
over
approximately half of the head splitting station. A cam track 110 following
the same
10 arcuate path is fastened to the arcuate plate 108 in a position lying
directly thereover
to span between the adjacent legs of the lower reinforcement 30, but instead
of
being horizontally flat like the support plate 108 beneath it, features a flat
central
portion and two inclined ramp portions sloping upward to the horizontal
central
portion at opposite ends thereof. As shown in Figure 2, the cam follower 104a
of
15 each control valve depends downward therefrom at a distance spaced above
the
lower reinforcement 30. The cam follower 104a, biased into its default lowered
position, is only elevated from this position as it travels over the cam track
110
during passage through the head splitting station.
Therefore, when the electric motor is operated to drive the main shaft
of the apparatus in the predetermined direction in which the loading,
splitting and
discharge stations are sequentially positioned in this order around the shaft
axis (i.e.
counterclockwise, as viewed from above, in the illustrated embodiment; Fig.
1), the
cam follower 104a remains in its default position until the control valve
reaches the
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entry ramp of the cam track at the beginning of the head splitting station.
The
default position of the cam follower 104a corresponds to the position of the
valve in
which the high pressure fluid conduit from the pump is communicated with the
top
port of the cylinder, thereby maintaining the cylinder's piston in a lowered
position in
which the respective head tray 22 is at a maximum distance below the
corresponding blade 66. Only when the cam follower rides up onto the cam track
110 does the position of the valve switch from this default position, and
instead
communicate the high pressure fluid conduit with the bottom port of the
cylinder to
drive the cylinder's piston upward and carry the respective head tray up to
the blade
66, thereby driving the animal head on the tray upwardly against the cutting
edge at
the bottom of the blade to split the head in two thereacross. As the cam
follower
completes its travel over the cam track 110 and thus returns to its lowered
default
position as it rides down the track's exit ramp, the valve returns to its
normal state,
pressurizing the top of the cylinder and driving the piston back downward to
lower
the head tray to its default lowered position. In Figure 2, the head tray on
the right is
lifted up against the blade since the respective cam follower is riding on the
cam
track in the first half of the cutting station, while the head tray on the
left is lowered
since the respective cam follower is hanging in its default position at the
cam-
trackless discharge station.
A discharge or unloading device 112 is mounted to the enclosure
discharge panel 92 at the discharge station of the enclosure and is operable
to
withdraw an animal head that has been split at the splitting station out of
the
enclosure interior from atop the head tray 22. A bracket 114 features two
horizontal
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members 116 diverging away from one another at oblique angles and a
horizontally
elongated plate 118 interconnecting the two members 116 in a vertical plane.
The
members extending in generally tangential directions relative to the circular
horizontal section of the apparatus enclosure and are fixed to the enclosure's
discharge panel or the upstanding frame legs at opposite ends thereof. A
horizontally oriented two-way pneumatic cylinder 120 is carried by the plate
118
interconnecting the two tangential members 116 so that its piston rod 122
extends
perpendicularly from the plate 118 between the tangential members on the side
of
the plate facing into the interior of the enclosure. At a distal end furthest
from the
cylinder 120, the piston rod 122 carries another vertically oriented plate,
the bottom
edge of which resides at an elevation slightly above the uppermost extent of
the
head trays of the head splitting units. This plate forms a plow 124 for
drawing the
split animal head outwardly off the head tray and through the discharge
opening in
the enclosure panel. A four-way two-position pneumatic solenoid valve 126 is
operable to selectively communicate a source of compressed supply air with
either
one of the cylinder's two ports depending on the position of the solenoid.
Figure 2 shows the extended position of the plow plate 124, which
corresponds to the cylinder rod 122 being extended to its maximum reach from
the
cylinder into the enclosure by actuating the solenoid of the valve to move out
of its
default state communicating the supply air with the inner end of the cylinder
to its
extended state communicating the supply air with the outer end of the
cylinder. This
extension of the cylinder positions the plow plate or blade 124 near the inner
end of
the head tray nearest the rotatable hub 38. The piston rod 122 and the upper
edge
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of the plow blade 124 are disposed at an elevation a short distance below the
lower
edge of the head splitting blades 66. The plow blade 124 is deployed to this
extended position near the hub 38 as a split animal head approaches the
discharge
device while transitioning between the head splitting and discharge stations
after
lowering of the head tray from the blade in the second part of the head
splitting
station. The rotation of the head tray and respective splitting blade toward
the now-
extended plow blade positions the plow blade between them near the hub, and
thus
behind the animal head. At this point, the solenoid actuating signal to the
pneumatic
valve 126 is removed, thereby returning the solenoid to its default retracted
position
opening the inner end of the pneumatic cylinder to the supply air to retract
the
cylinder's piston rod 122, thus pulling the plow blade 124, and the animal
head in
front of it, toward the discharge opening in the enclosure panel 92 beneath
the
discharge device 112, where the head is thus ejected. To maintain a fixed
orientation of the plow blade 124, additional guide rods or bars 128 are fixed
to the
plate at one end and slidably extend through holes in the bracket plate 118 in
directions parallel to the piston rod 122.
In operation of the apparatus, an operator stands at the loading station
and loads heads one at a time, each onto a tray positioned at or moving
through the
loading station. These trays are provided with suitable blocks or wedges for
supporting the heads in the desired position, as seen particularly in Figure
3. For
example, a hog's head inserted or loaded nose first into the enclosure and
forehead
down to the position where it is exposed centrally below the knife blade so
that when
the head tray is lifted up to the blade, the blade will split the head into
two
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substantially equal halves in the head-splitting station. The blades are
formed with a
recess in the splitting edge at the blade's bottom in a conventional manner to
avoid
cutting the organs.
Each head tray is in the default lowered position at all times except
when moving through the head-splitting station, and therefore it is in the
down
position when the head is loaded at the loading station. As a loaded tray
moves
through its rotational path around the shaft, the head tray remains in its
default
position spaced well below the respective blade until the head-splitting unit
enters
the head-splitting station. At that point, the control valve for the hydraulic
cylinder of
that head-splitting unit is triggered by engagement of its cam follower with
the cam
track, thereby causing the double-acting cylinder to drive the head tray
upwardly
through a head-splitting stroke. By the time the tray reaches its uppermost
position,
the head-splitting unit has advanced to a point in the head-splitting station
where the
cam follower defaults to its normal lowered position to cause the head tray to
go
through the return stroke and back to its default or home position. Two
identical and
parallel L-shaped wiper bars 130, as seen in Figure 1, extend upwardly from
the
base 52 of each head tray support 50 at the inner end thereof and then bend to
extend parallel to the base 52 a distance thereabove toward the outer end
thereof.
The horizontal spacing of these bars 130 accommodates the blade 66
therebetween
during the head splitting and retracting stroke, so that the bars will wipe
the head
from the blade as the tray is lowered should the head have a tendency to stick
to the
blade.
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=
Following the head-splitting operation, the head-splitting unit then
transitions into the discharge station, during which the pneumatic cylinder of
the
discharge device is extended so that continued rotation of the head tray
further into
the discharge station situates the plow blade of the discharge device in
position
5 behind the split head. The plow blade and the piston rod fit below the
wiper bars
when the head tray is properly seated in its fully lowered position. The
piston rod of
the pneumatic cylinder retracts, pulling the plow blade and the head outwardly
along
the head tray until the head falls from the outer end thereof through the
discharge
opening in the enclosure panel.
10 With reference to Figure 1, an electronic control panel 132 is
provided
to control operation of the system in view of user input on same. Preferably
the
control panel features a programmable logic controller (PLC) or other
computerized
control to monitor operating conditions of the apparatus and receive input
from the
operator, and set output signals to the appropriate equipment accordingly. The
15 preferred embodiment employs a graphical display screen to provide visual
feedback to the operator on the operational status of the machine and provide
prompts or options for user input. The user input may be implemented through
the
same display unit by using a touch screen device, or may be implemented
through
L
other controls such as a touch pad or physical button panel, or a combination
of
20 multiple input device types.
Further description of operation and control of the apparatus will now
be described with reference to an exemplary touch-screen PLC-based
implementation of the control system for which display screenshots are shown
in
CA 02732862 2011-02-18
21
Figures 5 to 9. In the illustrated screenshots, selectable onscreen buttons
have
rectangular shapes, while indicators reflecting the status of apparatus
components
or operation are circular to distinguish them from user-operable buttons.
From a selection screen shown in Figure 5, an operator has the option
to select from a "main screen", a "device screen", a "setpoint adjustment
screen" or
an "alarm summary screen". "Login" and "LogOut" options are also presented on
the main screen, as the preferred embodiment places password protection on the
availability of certain options in the control system, as will be described
herein further
below.
The main screen shown in Figure 6 presents the operator with several
options concerning operation of the machine. An onscreen button labeled
"Cleaning
Mode" is switchable between an "on" and "off' state. Cleaning mode is an
operational state of the apparatus in which the main shaft and the head
splitting
units carried thereon can be rotated together in the same manner as they are
for
performing head splitting operations, but in which the functionality of the
hydraulic
cylinders to lift and lower the head trays as they move through the head
splitting
station is disabled. This way, each head tray and its respective head
splitting blade
remain stationary relative to one another through each and every full or
partial
rotation of the shaft. Therefore, under cleaning of the machine by directing a
pressurized spray of water or other cleaning liquid or solution into the
interior of the
1
enclosure through the loading or discharge access openings in order to wash
down
the machine, the cleaning process is more effective as all of the head trays
remain
CA 02732862 2011-02-18
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at the same elevation throughout the machine's rotation, thereby maximizing
the
number of trays exposed to the spray at any given moment in time.
Referring again to Figure 6, pressing the "Cleaning Mode" button to
switch it from its normal "off' state to the "on" state changes the state of
an input on
the PLC controller, which in response to this change sends an output signal to
the
solenoid of the main hydraulic flow control valve 106, causing the valve to
move into
a closed position cutting off the supply of pressurized fluid from the pump to
the
hydraulic cylinders of the head splitting units. As a result, in subsequent
rotation of
the shaft and the head splitting units carried thereon, actuation of the
respective
cylinder control valve 104 as its cam follower 104a rides up onto the cam tack
110
will not act the raise the respective cylinder piston due to the lack of a
pressurized
fluid source available to flow through the valve 104 to the lifting-side lower
port of the
two-way cylinder 44. Any cylinder found in an extended/raised state in the
first
portion of the head splitting station when the cleaning mode is activated to
cut of the
hydraulic fluid supply will automatically return to the retracted/lowered
state when it
descends off the cam track 110 under subsequent shaft rotation, as the
switching of
the cylinder's control valve 104 back to its normal condition when its cam
follower
104a leaves the track 110 will open the previously pressurized portion of the
cylinder
below the piston to the previously, and still, unpressurized hydraulic return
path,
allowing the weight of the piston, head tray and head tray support to displace
the
fluid beneath the piston out of the cylinder. The pneumatic cylinder of the
discharge
device is also deactivated for cleaning mode operation by not sending any
solenoid
actuating signals to the pneumatic control valve 126 during such operation,
thereby
CA 02732862 2011-02-18
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maintaining the default retracted state of the plow blade throughout rotation
of the
head splitting stations around the axis.
Even in an alternate embodiment where the blades are lowered down
toward the head trays for the splitting operation, like in U.S. Patent Number
4,653,145, instead of lifting the head trays up to the blades as described
above for
the preferred embodiment of the present invention, there is still be an
advantage to a
cleaning mode where each tray and blade remain spaced apart through the
rotation,
as maintaining the raised position of the blade away from the tray would
improve
access of the spray to the full topside of each tray, as blocking of fluid by
the head
splitting blade is avoided as the head tray passes through the head splitting
station,
as the blade and head tray are left at their maximum separation from one
another at
all points in the rotation. Thus flow of fluid toward, onto, over or across
the topside
of the blade is not subject to interference by the blade that would otherwise
occur if
spraying was conducted while the blades moved through their normal head
splitting
cycles. However, the preferred embodiment uses the tray lifting configuration
described and illustrated herein so that any leakage of hydraulic fluid that
might
occur takes place beneath the trays so as not to contaminate the animal heads,
and
to simplify the cleaning mode operation by relying on gravity to keep the
cylinders
retracted, thereby making use of a simple "pump off signal to put the system
into
cleaning mode. Moving blade embodiments with overhead hydraulic actuators
could
still have a cleaning mode option where the blades remain in the retracted
positions
far from the trays, for example by using spring-return cylinders which will
automatically retract upward under spring force when fluid pressure is
removed,
CA 02732862 2011-02-18
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whereby disconnection between the pressurized fluid supply and the cylinders
for
cleaning mode operation would cause the blades to occupy and remain in their
spring-biased raised positions retracted upwardly from the head trays.
The main screen of Figure 6 also features onscreen "Jog Forward" and
"Jog Reverse" buttons, which when touched by the operator will send an output
signal from the PLC to the gear motor to rotate the motor for the duration of
the
button contact (i.e. run the motor until the operator "releases" the button).
The
"forward" direction jogs the motor in this manner in the predetermined
rotational
direction corresponding to the sequence of the loading, head splitting and
discharge
stations in this order around the shaft (i.e. counterclockwise in the
illustrated
embodiment), with the "reverse" direction thus being the opposite (i.e.
clockwise).
The jog function allows the operator to reposition the head trays around the
shaft
axis from a stopped condition of the shaft. For example, should an operator
fail to
properly seat an animal head at a head tray passing by the loading station
during
operation of the apparatus for head splitting, the rotation of the shaft can
be stopped
(in any of a number of manners described herein further below) and the "Jog
Reverse" button used to move the missed tray back to a suitable angular
position
about the shaft axis for access through the load access opening. Of course
this is
only one exemplary use of the jog function, and it may also be used to adjust
the
shaft's angular position for any other reason or purpose.
The main screen of Figure 6 also includes a number of indicators
switchable between "lit" and "unlit" or "highlighted" and "unhighlighted"
display
states, including "Hydraulics Off", "Air Off', "Table Forward" and "Table
Reverse"
CA 02732862 2011-02-18
indicators. The "Hydraulics Off' and "Air Off" indicators are respectively
highlighted
or lit up only when the supply of pressurized fluid for the hydraulic
cylinders of the
head splitting units is off and when the electrical supply for the solenoid of
the
pneumatic valve 126 is off (i.e. when the PLC program dictates that no
solenoid-
5 actuating output signal is to be sent to the pneumatic valve in rotation of
the
machine, such as in cleaning mode operation). One of the "Table Forward" and
"Table Reverse" indicators is highlighted or lit up when the shaft and
attached head
splitting units are rotating, the highlighted indicator reflecting the
particular rotational
direction of that motion.
10 An onscreen "Screen Select" button in Figure 6, also present in the
screenshots of Figures 6 to 8, returns the display to the "Screen Selection"
screen of
Figure 5 when pressed by the operator.
Still referring to Figure 6, an onscreen "Home Command" button
causes the PLC to send an output signal to the motor to rotate the shaft from
15 whatever it's current angular position to a default "home position",
which the PLC
determines has been reached upon receipt of an input signal from a proximity
switch
142 or sensor positioned to be triggered by contact with or detection of one
of the
head trays when the head tray is in the predetermined "home position". Figure
2
shows one of the head trays being located in the "home position" contacting
the
20 proximity switch 142 in the second half of the head-splitting
station at a location
aligning two other head trays with the discharge opening and loading opening
respectively. The ability to set the angular position of the main shaft into a
predetermined "home position" allows the rotary encoder to be of an
incremental
CA 02732862 2011-02-18
26
type that does not retain position or memory when powered down, as setting the
machine to the home positioning upon initial powering up of the control system
is
used to mark a fixed angular location around the shaft axis from which angular
movement of the shaft can be measured so that measured relative values from
the
encoder can be correlated to absolute locations of the head trays around the
shaft.
The home position need not necessarily align any tray with the loading or
access
openings in the enclosure panels.
Finally, the main screen of Figure 6 also features a "System Enable"
onscreen button, which when pressed switches the control system into an
enabled
state ready to operate the apparatus in either a head splitting mode or
cleaning
mode, depending on whether the "Cleaning Mode" button was set to "on" or
"off'.
When enabled, the PLC monitors for an input signal from a foot pedal
controller 134
(Fig. 1) that, in a conventional manner, has a button activated by foot
pressure to
close a normally-open momentary switch that maintains the closed condition of
the
switch only while the button remains depressed, and then automatically reopens
under release of the button by removal of the foot pressure. Receipt of the
input
signal at the PLC from the foot controller 134 causes an output signal from
the PLC
to the gear motor to drive rotation of the motor in the predetermined
direction, and so
holding down the footswitch causes continual rotation of the head splitting
units
around the shaft sequentially through the loading, head-splitting and
discharge
stations until the footswitch is released. In the head splitting mode (i.e.
with the
clean mode option "off"), the PLC has output signals to maintain the hydraulic
pump
in an active state so that the head splitting operation takes place as each
tray moves
CA 02732862 2011-02-18
27
through the head splitting station, and to switch the position of the
pneumatic valve
126 as each head moves through the discharge station to first retract the
pneumatic
cylinder as the tray passes the discharge opening and subsequently re-extend
the
pneumatic cylinder before the next tray reaches the discharge opening at the
discharge station. In cleaning mode, the cylinders (hydraulic and pneumatic)
are not
used, and so the PLC output is change to deactivate the pump and effectively
disconnect the compressed air source from the pneumatic cylinder.
The apparatus employs a number of safety devices connected to the
PLC controller to monitor conditions or receive input from the operator and
stop
operation of the apparatus should such conditions or input reflect a situation
warranting such action. With reference to Figure 4, an optical proximity
switch 136
is mounted on a guard plate 137 beside the access opening 94 at the loading
station
and positioned such that If the operator reaches too far into the machine
(i.e. past a
predetermined threshold distance) he or she will break the beam on the optical
sensor and cause the machine to stop operating, and a pull cord emergency shut
off
138 is suspended below the loading station access opening 94 and spans around
the enclosure from one side of the a control panel mounting plate 96 to the
other. In
a conventional manner, pulling the cord will withdraw a plug at one end
thereof from
a mating socket, breaking a current path to an input of the PLC, which
responds to
such signal loss by shutting down the motor to stop rotation of the head
splitting
units. A proximity switch 140 in Figure 2 detects retraction of the plow blade
at the
discharge station, with the PLC monitoring one of its inputs for a signal from
this
sensor after passage of sufficient time or shaft rotation to suggest that the
retraction
CA 02732862 2011-02-18
28
should be complete. The other proximity switch 142, the same as described
above
for use in determining the home position, is positioned late in the head
splitting
station (see Fig. 1) or early in the discharge station and similarly detects
successful
retraction of each hydraulic cylinder to lower the respective head tray to its
default
position before reaching the discharge device after the head splitting
operation, and
provides a corresponding signal to the PLC. A lack of "cylinder retracted"
signal
from either cylinder-monitoring proximity switch at a time or rotational
position at
which such a signal is expected based on the number of head splitting stations
equally spaced apart around the axis causes the PLC to interrupt the drive
signal to
the motor and thus cease operation of the apparatus. Magnetic switches are
used to
detect that each of the openable panels of the enclosure are in their closed
positions, and are wired together in a relay circuit connected to the control
panel to
interrupt or prevent operation of the electric motor if any one or more of the
switches
are open, indicating one or more panels are in the open position.
Figure 7 shows a "Device Screen" that can be selected from the
"Screen Selection" screen of Figure 5 for visual feedback on the status of
various
safety devices and inputs, for example to aid in trouble shooting the machine
when
the apparatus either automatically stops rotation during an operation, or
won't start
rotation in response to a "jog" input from the control screen or in response
to a
combination of a "system enable" input from the control screen and subsequent
foot
controller input. On this screen, the "Safety Photo Eye" indicator will be
highlighted if
the optical sensor 136 has been triggered, the "Plate Down" indicator will be
highlighted if one of the head trays failed to descend after the head
splitting station,
CA 02732862 2011-02-18
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the "Eject Retract" indicator will be highlighted if the discharge/eject
cylinder failed to
retract at the discharge station, the "E-stop relay in panel" indicator will
be
highlighted in response to detection by the PLC that the relay in the control
panel
has been tripped by unseating of one or more of the protective enclosure
panels
from its fully closed position, and a "Pull Cord Switch" indicator will
illuminate if the
emergency shut off cord has been pulled. A "Foot Switch" indicator illuminates
whenever no signal is received from the foot switch 134, an "E-stop local"
indicator
illuminates if depression of an emergency stop button 144 on the control panel
has
taken place to deactivate the motor output, a "Hydraulic Power indicator
illuminates
if a "stop pump" switch 146 or button on the control panel is pressed to
deactivate
the pump by disconnecting power to the drive motor thereof, and an E-Stop
Remote"
indicator illuminates if an emergency stop button 148 mounted remote from the
panel, for example near the access opening of the loading station on a support
leg of
the frame as shown in Figure 4, is pressed to stop the motor.
Figure 8 shows a "Setpoint Adjustment Screen" that can be accessed
from the "Screen Selection Screen" of Figure 5 if the user has logged in via
the
"Login Screen" of Figure 9, also accessed from the "Screen Selection Screen".
The
"Setpoint Adjustment Screen" provides selectable input fields for setting
different
operational parameters of the apparatus, particularly relating to operational
speeds
of the electric gear motor. The operator can change the "Running Speed" of the
machine, which refers to the rotational speed of the motor/shaft/splitting-
units
assembly under actuation of the footswitch, or the "Jogging Speed" which
refers to
the rotational speed of the motor while either of the "Jog" buttons is held
down for
CA 02732862 2011-02-18
manual positioning or fine-tuning of the angular position. In
the illustrated
embodiment, the speeds are expressed on the display screen in "Head/Hour to
reflect the number of animal heads that would be split under continuous
rotation at
the operator-set speed for one hour. In the illustrated embodiment having four
head-
5 splitting stations, four heads are split per full revolution of the
shaft, so the number of
heads per hour equals the revolution per minute of the shaft multiplied by 240
(Heads/Hr = Rev/Minute x Min/Hr x Heads/Rev = RPM x 60 x 4 = RPM x 240). The
control system may be configured to limit the range of user selectable speeds,
for
example from 800 to 1200 heads/hour (3-1/3 to 5 RPM) for the running speed and
10 200 to 800 heads/hour for the jogging speed. Changes in the different
speed values
affect the PLC's output signal to the motor running of the machine in foot-
pedal
operation (i.e. head-splitting or cleaning) and during manual jogging of the
machine
between such foot-pedal operations.
At higher rotational speeds of the shaft, the pneumatic cylinder should
15 be extended earlier in the shaft rotation than for lower rotational
speeds in order to
ensure that the plow blade reaches the extended position before the head tray
reaches the plow blade, otherwise the split head on the head tray will
interfere with
the extension of the plow blade, preventing it from getting behind the head as
required to then pull the head off the tray during the subsequent retraction
stroke. .
20 In one embodiment, when the PLC detects that user input has been received
to
change the running speed of the machine, and accordingly changes the output
signal that is output to the motor when the footswitch is depressed, it
automatically
changes the values of the angular positions of the shaft at which the
pneumatic
CA 02732862 2011-02-18
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cylinder of the discharge device is to be extended. Similarly, the system may
adjust
the values of the angular positions of the shaft at which the pneumatic
cylinder of the
discharge device is to be subsequently retracted after each extension in order
to
adjust the overall timing of the full discharge/ejection cycle relative to the
rotational
running speed of the shaft-carried head splitting stations for optimum
performance
using predetermined settings.
In other embodiments, the system may be configured to additionally or
alternatively give user-control over the timing of the ejection device
operation. For
example, Figure 8 shows two user-input "eject at" fields on the setpoint
adjustment
screen, one field being labeled with the embodiment's minimum selectable
running
speed (800 heads/hour) and the other labeled with the maximum selectable
running
speed (1200 heads/hour). The system stores data on an angular quantity, for
example a predetermined number of degrees, which represents a maximum offset
value that can be added to or subtracted from each default angular position of
the
shaft at which the pneumatic cylinder is to be extended as a head tray
approaches it.
Each of the two fields is labeled with a percentage symbol ( /0), to convey to
the
operator that they can enter an integer value between 0 and 100. A zero value
entered (zero offset) in either field means that, when the machine is set to
run at the
respective one of the minimum or maximum allowable running speed) the PLC, in
the head splitting mode, will send an actuation signal to the pneumatic
cylinder
control valve 126 every time the input from the encoder matches up to one of
the
predetermined angular positions (of which there are four, one for each head
tray). A
value of "100" entered in the minimum speed "eject at" field means that, with
the
CA 02732862 2011-02-18
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running speed set at the minimum selectable value of the predetermined range
(e.g.
800 heads/hour), 100% of the offset value will be added to the default
"cylinder
extension" angular position so that the pneumatic cylinder will extend when
the shaft
has reached the maximum offset number of degrees past the default position in
the
head splitting mode. A value of "100" entered in the maximum speed "eject at"
field
means that, with the running speed set at the minimum selectable value of the
predetermined range (e.g. 1200 heads/hour), 100% of the offset value will be
subtracted from the default "cylinder extension" angular position so that the
pneumatic cylinder will extend when the shaft the maximum offset number of
degrees before the default position. Should the user enter a running speed
having a
value between the minimum and maximum values of the allowable range, the PLC
can use the maximum and minimum allowable running speeds and their two offset
percentages together with this input running speed to interpolate an offset
percentage to use to calculate the user-adjusted "cylinder extend" angular
positions
of the shaft. Giving user-control over the relationship between the rotational
speed
of the machine and the ejection cycle allows an operator to fine tune
performance at
the discharge station to better ensure proper ejection of split heads from the
machine to minimize machine downtime.
Figure 9 shows the "Login Screen". Selecting the "Name" or
"Password" field brings up the keyboard screen to enable the operator to enter
characters into the corresponding field. An onscreen "Home" button takes the
user
back to the "Screen Selection" screen, an onscreen "Arrow" button takes to the
user
to the "Setpoint Adjustment Screen", and an onscreen "Lock/Key" button logs
the
CA 02732862 2011-02-18
33
user in after having entered a valid usemame and password combination. Using
password protected access to the "Setpoint Adjustment Screen" is useful, for
example, to limit speed adjustment to only authorized personnel (e.g. plant
management), for example to use lower speeds for training new operators and
allow
higher speeds for experienced operators capable of handling greater throughput
at
the machine in a safe and effective manner.
Figure 10 shows an "Alarm Summary Screen" selectable from the
"Screen Selection" screen of Figure 5. Here, information on alarm events that
previously prevented or ceased operation of the apparatus is summarized based
on
data recorded by the control system when such alarm events took place. The
information in the illustrated embodiment includes a message indicating the
type of
alarm event (emergency cord pull, open enclosure panel, emergency stop relay
button actuation, etc.) and the date and time at which the event occurred,
organized
in a table layout. User-selectable buttons are presented to allow operator-
controlled
sorting of the listed events based on different criteria.
The preferred embodiment of the present invention benefits not only
from the from the unique "cleaning mode" operation, in which efficient and
thorough
spray down of the machine can be performed by maximizing exposure of the head
trays to a cleaning fluid being sprayed into the machine from a stationary
point by
rotating the head splitting stations around the machine with the trays and
blades
maintained in a spaced apart condition throughout the rotation, but
additionally offers
advantages over prior art machines employing hydraulic rotational drives. The
combined use of an electric motor and PLC, or other computerized control
system
CA 02732862 2016-02-10
34
trays to a cleaning fluid being sprayed into the machine from a stationary
point by
rotating the head splitting stations around the machine with the trays and
blades
maintained in a spaced apart condition throughout the rotation, but
additionally offers
advantages over prior art machines employing hydraulic rotational drives. The
combined use of an electric motor and PLC, or other computerized control
system
employing a processor to execute a machine readable program instructions
stored in
computer readable memory to monitor incoming signals and accordingly adjust
output signals to the equipment being controlled, allows owners, operators or
other
personnel to easily modify operational aspects of the machine through a
computerized user interface, thus avoiding having to swap out or manually
adjust
hydraulic control components. It also gives the option of being able to
password-
protect access to these settings to limit who is able to change operational
parameters of the machine.
Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same made
within the scope of the claims without departure from such scope, it is
intended that
all matter contained in the accompanying specification shall be interpreted as
illustrative only and not in a limiting sense.
