AU768408B2 - Animal head removal - Google Patents

Description

P/00/0oII Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION Invention Title: ANIMAL HEAD REMOVAL The following statement is a full description of this invention, including the best method of performing it known to me: -2- ANIMAL HEAD REMOVAL FIELD OF THE INVENTION This invention relates to the removal of animal heads from carcasses of slaughtered animals in an abattoir. In particular, but not solely the invention relates to the removal of heads from slaughtered sheep transported on a conveyor chain in a freezing works.

BACKGROUND

By way of example, in New Zealand, after the animal is stunned and slaughtered, the removal of sheep heads has generally been a two operator job. The first operator twists the neck to loosen or break the cartilage between the atlas and the skull and the second operator uses a knife to sever the cartilage and the head is released from the carcass. Both operations have a high incidence of Repetitive Strain Injury (RSI/OUS) associated with them.

The process for the removal of cattle heads is carried out by one operator, with the operator using a knife to sever the cartilage between the skull and the atlas. However this too is subject of injury.

It is an object of this invention to provide an improved method and/or apparatus for the removal of animal heads or that will at least provide the industry with a useful choice.

BRIEF DESCRIPTION OF INVENTION In accordance with the invention there is provided an apparatus for the removal of a head from the carcass of a slaughtered animal, the apparatus able to be positioned alongside a chain in a freezing works and to sever the head as the carcass moves along the chain, the apparatus including: a linearly moveable blade which is operated with a substantially linear driving force and velocity, means for detecting the position of the head of the animal relative to the blade, means for loosely retaining the animal's head within a confined area, and means for applying sufficient substantially linear driving force and velocity to move the blade to sever the animals head at or in the direction of the atlas joint of the carcass, whereby in use the apparatus can provide a combination of the applied linear driving force r4 -3and velocity sufficient such that, even if the blade misses the preferred spot, it will still sever the head from the carcass.

The means for detecting the position of the carcass includes a movement detector that senses the presence of the carcass moving along the chain towards the apparatus.

The apparatus is adapted to work with the animals in the inverted dressing system in which animals are hung upside down from the chain and suspended from their legs with the head hanging down below the body, and wherein the means for detecting the position of the carcass includes a head sensor to detect the position or height of the animal's head relative to the blade or the ground.

The head sensor can have a moveable nose plate.

The nose plate is designed to come into contact with the head of the animal to detect its height above the ground and is adapted to move quickly out of the way after detecting the position of the animal's head. The nose plate is pivotally connected to a frame which supports the movable blade.

S. The means for positioning and holding the animal's head can include a rear head arm capable of moving onto and out of contact with the rear of the animal's neck during the cutting operation.

S The means for driving the blade is an hydraulic ram.

The invention also provides a method for the removal of a head from the carcass of a slaughtered animal, wherein the method involves locating a carcass relative to a movable blade, locating the position of the head of the carcass relative to the blade, aiming the S movable blade at or in the direction of the atlas joint of the carcass, and moving the blade at a high speed and with sufficient applied pressure to remove the animal head at the atlas 2 ,5 joint or through the bone (if the motion of the carcass relative to the machine results in the blade missing the atlas joint).

The blade can be moved by means of a hydraulic ram at a pressure in excess of 1000psi.

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DRAWINGS

In order that the invention can be more readily understood an embodiment will be described by way of illustration only with reference to the drawings, in which: Figure 1 is a front perspective view of a head removal apparatus in accordance with a first embodiment of the invention with protective housing removed; Figure 2 is a rear perspective view of the head removal apparatus of Figure 1 with protective housing removed; Figure 3 is a top plan view of the apparatus shown in Figure 1 with protective housing; Figure 4 is a front elevation of the apparatus shown in Figure 1 with protective housing; Figure 5 is a side elevation of the apparatus shown in Figure 1 with protective housing; Figure 6 is a top plan view of the cutting blade of the apparatus shown in Figure 1; Figure 7 is a front elevation of the cutting blade shown in Figure 6; S Figure 8 is a top perspective view of the cutting blade shown in Figure 6.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to the drawings there is shown an apparatus for the removal of a head from the carcass of a slaughtered animal, the apparatus is able to be positioned alongside a chain in a 2.0 freezing works and to sever the head as the carcass moves along the chain.

o*o* The apparatus has a central pedestal mount 2 with a mounting plate 1 bolted to the floor.

From this central mount there is attached by means of a single pivoting arm 20, a frame 13 providing a skeleton for the attachment of cutting means 30, washing means 33, 34 and powering means 31 for the blade of the cutting means 30. The apparatus includes a i L I moveable blade as part of the cutting means 30 which is operated with a substantially linear driving force and velocity by the powering means 32.

The frame 13 is substantially U-shaped being comprised of two parallel longitudinal members connected at one respective end by a cross member 15. The frame 13 is connected to the central mount by an elongated cylindrical pivoting arm 20 which extends across the U-shaped frame 13 and which pivotally connects with downward extending plates attached from the two parallel longitudinal members such that the frame 13 is able to pivot from an idling position in which the frame 13 is angled at approximately 40 degrees to the horizontal with the end supporting the cutting means 30 lower-most to an operating position in which the frame is substantially horizontal. Adjacent to the central support 2 attached at ground level 4 to the ground plate and to the downward extending plates attached from the two parallel longitudinal members there is provided a ram 5 which is capable of driving the frame 13 from an idling position to an operating position.

At four spaced points on the two parallel longitudinal members of the frame 13 there are brackets 14 for the attachment of a substantially rectangular frusto-pyramidal safety cover 29. Two groups of the points are each equidistant from the cross member 15 on the superior surface of the frame 13 but with the groups spaced relative to each other. At a central outer point on the rear edge of the cross member 15 of the frame is a guide 16 for

O

o the alignment of the safety cover 29 so that it substantially coextends with the U-shaped 0 frame and covers the mechanisms below.

The apparatus further includes means for detecting the advance of the carcass relative to the blade, means for detecting the position of the head of the animal relative to the blade, being a head sensor 18, means for steadying the animal's head including rear head bar 8, 9, and means for applying sufficient substantially linear driving force and velocity being the 0-24 powering means 32 to move the blade to sever the animals head, whereby in use the combination of the applied driving force and velocity is sufficient such that, even if the blade misses the preferred spot, it will still sever the head from the carcass.

One of the two parallel longitudinal members 13 of the U shape frame is longer than the other. The head sensor 18 is attached to the shorter of the two parallel longitudinal -6members of the frame 13 and a rear head bar 8, 9 is attached to the longer member to provide a closing of the U shape frame 13 with the head sensor 18. The rear head bar 8, 9 is made up of two different length overlapping elongated members with both mounted on a U-shaped bracket 10 extending from the longest elongated member 13 and partially inwards but in the plane of the U-shaped frame 13. A pivoting arm 11 in the form of a pin extends across the U-shaped bracket and normal to the plane of the U shaped frame 13 such that the rear head bar 8, 9 extends and rotates in the plane of the frame 13. The first member 8 is the longest and is attached along a middle section to the pivoting arm 11. The second member 9 is shorter and coextends above the first member from the pivoting arm 11 to an end of the portion of the first member 8 that assists closing off the open end of the Ushaped frame. The first and second members are maintained at a distance from each other by their connection to the pivoting arm 11 and by a spacer 12 at the respective distal ends of the first and second members thus leaving a slot like opening therebetween. There is sufficient distance between the two members 8, 9 such that the blade of the cutting means 30 can pass between.

A ram 6 which drives the rear head bar 8, 9 is attached to the outer side of the longer longitudinal member 13 two thirds of the distance along the said member from the rear edge 15 of the frame. The ram 6 is attached to the rear head bar at the overhang end 7 of the longer member 8 and thereby causes the rear head bar 8, 9 to pivot around the pivoting .2Q arm 11.

The means for detecting the advance of the carcass relative to the blade is an optical sensor switch (not shown) which is located on the chain carrying the carcass. This switch senses the passage of carcass past a point along the chain at which a cut cycle should be initiated.

At the initiation of the cut cycle the frame 13 rotates under the power of ram 5 from the °245 o idling position towards the operating position. Rotation of the frame 13 continues until the 0000 head sensor 18 contacts the nose of the carcass. The head sensor 18 is located on the opposite longitudinal section of the frame 13 to the attachment of the rear head bar, and lays on the outer side of the frame 13 and supported at right angles by two supporting members 19. The head sensor comprises a scooped nose plate 18 connected by the two parallel supporting members 19 attached at their proximal end to a pivoting arm 22 which is e D -7suspended from a bar 21 by two brackets 27, one at each end of the pivoting arm 22.. The scooped nose plate 18 is thereby alongside but beyond the end of the shorter elongated member 13 of the frame.

A bracket 23 is rigidly attached to the inner most supporting member 19 and extends away from the nose plate 18, and at a point distal from the nose plate 18 supports a target for a proximity switch. The mating proximity switch is supported on a bracket secured to frame 13. A ram 28 is connected at one end to a bracket 26 supported on frame 13, and at the other end to bracket 23.

At the beginning of a cut cycle, as the frame 13 begins to rotate from the idle position the nose plate 18 is designed to come into contact with the nose of the animal supported on the chain and in this way provide an input to the apparatus via the proximity switch to indicate the vertical position of the head of the animal. This enables the apparatus to determine the preferred angle of the frame 13 in which to carry out the cutting operation for the particular animal. In a preferred embodiment, once contact is made with the head of the animal, the ram 28 can be used to rotate the nose plate 18 downwards to move it out of the way of the animal during the remainder of the cut cycle.

The nose plate 18 has a flat central section with parallel outer upwardly extending flaps.

The nose plate is designed to prevent the nose from slipping from the vertical as the nose plate pivots upwards to make contact with the nose. Figure 1 shows the sensor 18 with parallel outer flaps 17 at 30 degrees approximately extending from the flat central section of the nose plate to thereby prevent the nose from slipping from the vertical as the nose plate pivots upwards to make contact with the nose.

Whilst the pivoting nose plate works another advantageous variation is a two part movement which would drop the arm down and bring it up to the nose at an angle parallel to the floor ensuring that the first contact with the nose will give an accurate reading of the position of the head. Preferably a two part movement will enable the nose plate to consist of a substantially flat plate sensor.

The conversion of the distance from the floor to the nose of the animal to the position of the blade at the atlas bone is achieved using a rotary encoder (1 revolution 2000 pulses). The nose to floor distance is translated into degrees of movement that the blade must turn through to achieve the preset distance which ensures the severing of the head at the atlas bone. This is based on the fact that the distance from the nose to atlas bone is relatively constant in each species/breed/line/age group of animals being slaughtered and that this distance may be preset so that once the nose plate has taken a reading of where the nose is relative to the floor the machine then moves to the preset distance and the blade is in place.

The head sensor is also fitted with a trim switch which enables an operator to manually trim the preset distance should the blade consistently appear to require an adjustment so that the atlas bone is severed; which may occur when a line of animals, that are consistently greater or lesser than the preset distance allowed for, enters the chain.

Preferably the cutting means 30 is comprised of hardened steel, weighing approximately kg, with dimensions of 300mm x 200mm with a 200 chamfer on both asides of the cutting edge. On the back edge of the blade there is a cutaway section 42 which allows for position of the clevis 24 of the ram and one or more attachment points 41 for the blade to a mounting plate 25 which is attached at each side to the guide shafts 32. The ram achieves a speed of approximately 1 metre power second through the pressure created by a 1 I kWatt power pack driving a 50mm piston and a 400 mm stroke to result in a pressure of approximately 2000psi.

o: Once the cut cycle has been completed the blade is retracted and hot water is dispensed over the blade from hot water pipes 33, 34. The hot water pipes 33, 34 originate just past the pivot point of the frame and extend forwards towards and around but clear of the cutting blade 30. They are supported from within the inside edge of the frame and have outlets 36 which are directed onto the blade..

In use, as shown particularly in Figure 4 the incoming sheep carcass is suspended on all 2 four points (using the inverted dressing system) in a supine position with the shoulders slightly lower than the hips presenting the head hanging down and the throat foremost to the blade. The pelt is well pared back from the throat and neck region so that contamination from the fleece is minimised. The presence of the sheep is detected by a photo switch attached to the chain which activates the movement of the frame 13 away from the idling position towards the operating position such that the head sensor 18 is carried up so that the nose plate of the head sensor makes contact with the animal's nose and provides a measurement from which the angle at which the blade should operate is determined.

The head sensor being a trough shape nose plate pivots about one or more points so that the nose plate is presented to the nose of the animal at right angles. The trough shape of the nose plate encourages the nose to return to the vertical position, thus ensuring an accurate measurement of the height of the nose to the floor and consequently an accurate positioning of the blade to the atlas.

The rear head bars 8, 9 pivot about a single point powered by a ram to swing forward and rest on the back of the animal's head simultaneously as the axe blade 30 comes forward and severs the head.

A switch attached to the chain detects that the sheep is on the centre line of the blade and the cut cycle is initiated. The blade retracts into the wash cabinet and the machine lowers and resets ready for the next animal.

All of this happens quickly with the carcass moving along the chain without stopping. The apparatus can be fixed to the floor and does not need to move with the chain.

e* It should be understood that the above embodiment is by way of illustration only. Clearly variations which are readily understood by a person skilled in the art without any 100 inventiveness are included within this invention as defined in the following claims.

Claims (12)

1. Apparatus for the removal of a head from the carcass of a slaughtered animal, the apparatus able to be positioned alongside a chain in a freezing works and to sever the head as the carcass moves along the chain, the apparatus including: a linearly moveable blade which is operated with a substantially linear driving force and velocity, means for detecting the position of the head of the animal relative to the blade, means for loosely retaining the animal's head within a confined area, and means for applying sufficient substantially linear driving force and velocity to move the blade to sever the animals head at or in the direction of the atlas joint of the carcass, whereby in use the apparatus can provide a combination of the applied linear driving force and velocity sufficient such that, even if the blade misses the preferred spot, it will still sever the head from the carcass.

2. Apparatus as claimed in claim 1, wherein the means for detecting the position of the carcass includes a movement detector that senses the presence of the carcass moving along the chain towards the apparatus.

3. Apparatus as claimed in any one of the preceding claims, wherein the apparatus is adapted to work with the animals in the inverted dressing system in which animals are 20 hung upside down from the chain and suspended from their legs with the head hanging down below the body, and wherein the means for detecting the position of the carcass includes a head sensor to detect the position or height of the animal's head relative to the blade or the ground.

4. Apparatus as claimed in claim 3, wherein the head sensor has a moveable nose plate.

5. Apparatus as claimed in claim 4, wherein the nose plate is designed to come into contact with the head of the animal to detect its height above the ground and is adapted to move quickly out of the way after detecting the position of the animal's head. -11

6. Apparatus as claimed in claim 4 or 5, wherein the nose plate is pivotally connected to a frame which supports the movable blade.

7. Apparatus as claimed in any one of the preceding claims, wherein the means for positioning and holding the animal's head includes a rear head arm capable of moving onto and out of contact with the rear of the animal's neck during the cutting operation.

8. Apparatus as claimed in any one of the preceding claims, wherein the means for driving the blade is a hydraulic ram.

9. A method for the removal of a head from the carcass of a slaughtered animal, wherein the method involves locating a carcass relative to a movable blade, locating the position of the head of the carcass relative to the blade, aiming the movable blade at or in the direction of the atlas joint of the carcass, and moving the blade at a high speed and with sufficient applied pressure to remove the animal head at the atlas joint or through the bone even if the motion of the carcass relative to the machine results in the blade missing the atlas joint.

10. A method as claimed in claim 9, wherein the blade is moved by means of a hydraulic ram at a pressure in excess of l00psi.

11. A method substantially as herein described with reference to any one of the S accompanying drawings. •*ooo

12. Apparatus substantially as herein described with reference to any one of the accompanying drawings. ooo•.