AU2018203246A1 - Tunnel boning apparatus and method of tunnel boning - Google Patents

Abstract

A tunnel boning apparatus and an associated method are described to automate the process of tunnel boning a leg meat cut, particularly a lamb leg.

Description

TUNNEL BONING APPARATUS AND METHOD OF TUNNEL BONING

TECHNICAL FIELD

Described herein are tunnel boning apparatus and a method of tunnel boning. More specifically, apparatus and an associated method are described to automate the process of tunnel boning a leg meat cut, particularly a lamb leg.

BACKGROUND ART

In general, automation of meat processing steps is a common trend as demands increase for great worker safety, higher meat yields, lack of labour on hand especially in remote locations to perform meat processing and so on.

One meat processing step is that termed 'tunnel boning'. For lamb, this is the step of removing the leg bone from the meat whilst retaining the various muscles together. Reference is made to lamb processing hereafter however, the same device may be used to tunnel bone other meat pieces having a centrally located bone encircled by meat and reference to lamb or a lamb leg should not be seen as limiting.

Traditionally, when tunnel boning of a lamb leg is completed by hand, the first step required is to remove the aitch bone at the wide end (hip end) of the leg. This is done manually by following the contour of the bone with the point of a knife and cutting through the cup joint. Next it is necessary to remove the meat from around the end of the leg bone that was connected to the cup joint. This may be done with the top of a knife in a scraping action, pushing the meat back down to expose the bone. Cutting then shifts to the other end of the leg and cutting is completed on either side of the leg bone (following the edge of the shank or shin) down to the knee joint. Care needs to be taken at this point to avoid cutting through the knee joint. Then the meat is scrapped off the bone as before. Finally the leg bone is removed by laying the leg flat on a bench, grasping one end of the leg bone and twisting the leg bone until the meat releases and then pulling the leg bone clear of the leg. Once this is completed, the fat kernel may be removed which is located between the topside and the silverside muscle. A skilled processor may take approximately 2-5 minutes to complete this process before moving on to the next lamb leg for processing.

Besides the fact that the above processing requires significant skill, labour and time, the process described may have other unwanted drawbacks such as:

- Risk of contamination through poor handling procedures;

- Risk of unnecessary or unwanted meat cutting leading to product downgrades;

- Risk of bone breakage when the bone is removed.

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Providing an apparatus to automate parts of the process described and in doing so addressing at least one of the drawbacks of manual processing may be helpful.

One art reference¹ reiterates some of the advantages and issues noted above. On a positive note, the art reference states that automation of, or mechanical assistance with, boning tasks promises big advantages in terms of process efficiency and employee health and safety. Also as noted in this reference, automated apparatus may be expected to:

- Enhance process and product versatility;

- Be safe and simple to operate:

- Be robust, hygienic and functional in design and construction;

- Be easy to clean; and

- Be modular - each machine standing alone yet complementary in a system.

The art reference describes a device used to remove the leg bone from a meat cut, the device developed primarily for the mutton boning industry, to bone either chilled or pre- rigor legs. As noted in the above reference 'product comes off the machine as a tunnel-boned leg with the patella still in the meat. The leg 15 deboner is a compact stand-alone unit reguiring air and electrical services. It [the meat piece and bone inside] is loaded from the front with automatic ejection of product and bones. Boning is performed by the scraping and cutting action of two chucks, which simultaneously separate the meat and bone from both ends until the chucks meet in the middle. The bone is then ejected through the hollow lower chuck'.

Despite some promising calculations in the art reference around increased yield and return on investment, the reference notes that the first sale in Australia did not eventuate until almost 10 years later and, when the reference was written, only 13 units had been sold, sales being static since 2002. The reference notes that the experience was 'less than desired'.

Aspects of the leg deboner of the above reference that the inventors have noted in their own work as being undesirable are:

- The end of the chucks that engage the bone ends are regular and flat in shape whilst the ends of a leg bone are irregular. The chucks shown would inherently have trouble engaging and/or remaining engaged with the leg bone ends.

- As noted, one of the chucks is hollow and the leg bone is pushed through the hollow chuck. Leg bones are irregular in shape and hence would in the inventors experience jam up about the chuck opening unless a large tolerance opening is provided that would lead to poor yields due to cutting not being at the bone/meat interface.

- The meat around the bone would potentially slip and move about the chucks since there is no bearing face as removal occurs hence resulting in a lower yield than desired;

- The chucks do not have a variable radius jaw face and do not move eccentrically hence could ¹ Meat Technology Update - 4/06 August 2006 - Towards Automated Boning - A Case Study: Sheep Boning Eguipment

2018203246 10 May 2018 not cater for variations in shape along the bone longitudinal axis as the chuck travels along the bone. The chucks would either need to be oversized relative to the leg bone (in order to fit over a range of bone diameters) or would struggle to meet the variability needed to confirm to the wide variety of natural variation in leg bone diameter;

- The chucks are also fixed along the common shaft so as to meet together about a central point.

This means they inherently cannot address eccentricity in bone shape along the leg bone length - leg bones are rarely straight and have a bend or bends hence a fixed position jaw would not confirm to the leg bone shape during cutting.

Further aspects and advantages of the tunnel boning apparatus and method of tunnel boning will become apparent from the ensuing description that is given by way of example only.

SUMMARY

Described herein are apparatus and an associated method to automate the process of tunnel boning a leg meat cut, particularly a lamb leg.

Tunnel Boning Apparatus - Pushing Action

In a first aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends; and;

when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face while the meat bears against the bearing face surrounding at least part of the opening and is removed from the bone as the bone is pushed through the bearing face opening.

Tunnel Boning Apparatus - Jaw Shape

In a second aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the

2018203246 10 May 2018 shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the opening, meat on the meat piece is cut and subsequently lifted from the bone by the cutting assembly or a part thereof.

Tunnel Boning Apparatus-Jaws Move Eccentrically

In a third aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the 15 opening, the cutting assembly or a part thereof moves at least partly about a plane eccentric to the shaft longitudinal movement axis.

Tunnel Boning Apparatus - Clamp Shape

In a fourth aspect, there is provided a tunnel boning apparatus comprising:

An axially aligned stem shaft and clamp shaft, the shafts configured to retain opposing ends of a 20 bone in a meat piece between the first ends;

wherein the stem shaft comprises a first end with a dual prong shape, the prongs configured to accept and conform to a hip end of a leg bone so that the region between a head and a greater trochanter of the leg bone nests between the prongs; and wherein the clamp shaft comprises a first end with a dual prong shape, the prongs configured to 25 accept and conform to the knee end of a leg bone so that a patellar surface between a medial condyle and a lateral condyle of the leg bone nests between the prongs.

Method

In a fifth aspect, there is provided a method of tunnel boning a meat piece, the method comprising the steps of:

selecting an apparatus substantially as hereinbefore described;

positioning the meat piece and bone therein between each shaft first end;

actuating synchronised shaft movement so that the meat piece bone is pushed from the meat piece meat.

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Advantages

The apparatus described has a variety of advantages over both manual and art automated apparatus and methods of tunnel boning. Selected advantages may comprise:

- The shaft first ends are configured to engage and conform to the bone end shapes hence provide a strong retaining force to hold the bone during meat removal.

- Leg bone shape irregularities are addressed through movement of the cutting assembly or a part thereof during bone removal;

- A consistent singular load force may be applied to the meat piece bone during bone removal leading to lower risk of apparatus damage or meat contamination;

- Bone pushing in one direction as opposed to bone pulling leads to reduced risk of bone fracture;

- The apparatus has a high and consistent meat yield and low/no risk of contamination or meat downgrade through incomplete bone removal;

- The apparatus may cater for varying bone length and diameter.

The embodiments described above may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features.

Further, where specific integers are mentioned herein which have known equivalents in the art to which the embodiments relate, such known equivalents are deemed to be incorporated herein as of individually set forth.

BRIEF DESCRIPTION OF THE DRAWINGS

Further aspects of the tunnel boning apparatus and method of tunnel boning will become apparent from the following description that is given by way of example only and with reference to the accompanying drawings in which:

Figure 1 illustrates a diagram of a lamb leg;

Figure 2 illustrates an embodiment of a tunnel boning apparatus;

Figure 3 illustrates a diagram from above of the apparatus;

Figure 4 illustrates a detail view of a lamb bone retained by compression force between the stem shaft and clamp shaft;

Figure 5 illustrates a detail view of a meat piece including meat on a bone retained by compression force between the stem shaft and clamp shaft;

Figure 6 illustrates a detail view of a first head of a clamp shaft and a surrounding cutting assembly;

Figure 7 illustrates diagram of the cutting assembly in a jaws closed position;

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Figure 8 illustrates a side view of the cutting assembly and its bearing face interaction with the frame;

Figure 9 illustrates an example of removable jaw parts;

Figure 10 illustrates a diagram of one half of a removable jaw part;

Figure 11 illustrates a diagram side view of one half of a jaw part;

Figure 12 illustrates a top view of a stem shaft and bush;

Figure 13 illustrates a diagram in side and top view of a stem shaft;

Figure 14 illustrates diagram in top and end on view of the stem shaft end prong detail;

Figure 15 illustrates the stem shaft end prong detail;

Figure 16 illustrates the clamp shaft end prong detail;

Figure 17 illustrates the apparatus in use, in this view with the meat piece loaded and leftward axial movement commenced with the meat piece having been moved to bear against the cutting assembly;

Figure 18 illustrates a next removal step with the bone beginning to be pushed from the meat, the bone starting to protrude into the secondary area;

Figure 19 illustrates a next removal step with the bone pushed from the meat, the bone in the secondary area and the meat separated and resting on the stem shaft;

Figure 20 illustrates a next removal step with the bone dropping away from the shafts as the stem shaft returns to a right side home position, the meat travelling with stem shaft rightwards;

Figure 21 illustrates a next removal step with the stem shaft retracting through the right frame and the 20 meat bearing against the right frame; and

Figure 22 illustrates a next removal step with the meat falling away from the stem shaft as the stem shaft mostly retracted through the right frame to a home position.

DETAILED DESCRIPTION

As noted above, described herein are apparatus and an associated method to automate the process of tunnel boning a leg meat cut, particularly a lamb leg.

For the purposes of this specification, the term 'about' or 'approximately' and grammatical variations thereof mean a quantity, level, degree, value, number, frequency, percentage, dimension, size, amount, weight or length that varies by as much as 30, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1% to a reference quantity, level, degree, value, number, frequency, percentage, dimension, size, amount, weight or length.

The term 'substantially' or grammatical variations thereof refers to at least about 50%, for example 75%,

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85%, 95% or 98%.

The term 'comprise' and grammatical variations thereof shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements.

For the purposes of this specification, the term 'meat piece' or grammatical variations thereof, prior to processing, refers to a mass of meat (termed 'meat' hereafter) with at least one bone extending substantially longitudinally through the meat.

For ease of description and understanding herein, reference is made herein to lateral movement of the shafts and optionally a meat piece if in the apparatus and with movement being in a substantially horizontal plane left or right. As should be appreciated, the shaft longitudinal axis need not be in a horizontal plane and references to left or right movement could instead be up or down or side to side. Further, reference t right or left may be swapped, for example by swapping the part orientation and reference to 'right' or 'left' herein should not be seen as limiting in terms of the apparatus operation.

Tunnel Boning Apparatus - Pushing Action

In a first aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends; and;

when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face while the meat bears against the bearing face surrounding at least part of the opening and is removed from the bone as the bone is pushed through the bearing face opening.

Tunnel Boning Apparatus - Jaw Shape

In a second aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so

2018203246 10 May 2018 that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the opening, meat on the meat piece is cut and subsequently lifted from the bone by the cutting assembly or a part thereof.

Tunnel Boning Apparatus-Jaws Move Eccentrically

In a third aspect, there is provided a tunnel boning apparatus comprising:

a bearing face;

an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the opening, the cutting assembly or a part thereof moves at least partly about a plane eccentric to the shaft 15 longitudinal movement axis.

Tunnel Boning Apparatus - Clamp Shape

In a fourth aspect, there is provided a tunnel boning apparatus comprising:

An axially aligned stem shaft and clamp shaft, the shafts configured to retain opposing ends of a bone in a meat piece between the first ends;

wherein the stem shaft comprises a first end with a dual prong shape, the prongs configured to accept and conform to a hip end of a leg bone so that the region between a head and a greater trochanter of the leg bone nests between the prongs; and wherein the clamp shaft comprises a first end with a dual prong shape, the prongs configured to accept and conform to the knee end of a leg bone so that a patellar surface between a medial condyle 25 and a lateral condyle of the leg bone nests between the prongs.

Method

In a fifth aspect, there is provided a method of tunnel boning a meat piece, the method comprising the steps of:

selecting an apparatus substantially as hereinbefore described;

positioning the meat piece and bone therein between each shaft first end;

actuating synchronised shaft movement so that the meat piece bone is pushed from the meat piece meat.

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Tunnel Boning

As may be appreciated, tunnel boning refers to a process in meat production whereby a longitudinal bone is removed from a meat piece, leaving the meat intact and, once the bone is removed, leaving a 'tunnel' through the meat corresponding to the original bone location prior to bone removal. Using a leg 5 of lamb as a specific example, the leg bone is removed from the leg of lamb leaving the muscles (meat) including the knuckle, the topside and the silverside intact and connected. Tunnel boning is a common manual processing step however, in the inventors experience, it is rarely automated.

Bearing Face

The term 'bearing face' as used herein refers to a frame, face, plate or other structural element that meat from a meat piece bears against when relative movement occurs between the shafts/meat piece and the bearing face or part thereof. As should be appreciated, the bearing face obstructs meat movement with the bone. The bearing face may not be itself fixed in place although could be fixed if desired. For ease of description hereafter, movement of the shafts is described relative to a fixed bearing face. This should not be seen as limiting since the bearing face may move relative to fix shafts without departing from the scope of the apparatus and method described herein.

The apparatus may be defined by a central area framed on either side by first and second frames, this central area being where the meat piece is loaded between the shafts and, post bone removal, where the meat piece may drop from. The bearing face (or multiple bearing faces) may be located in this central area.

To one side of the central area may be a secondary area where the bone is pushed to and which lies behind a first frame. This secondary area may be partitioned from the meat on the meat piece during all stages of meat piece processing by the first frame.

A further tertiary area may be positioned opposite the first plate defining the opposing side of the central area. A stem shaft actuator and subassembly may be located in the tertiary area. The tertiary 25 area may again be partitioned from the meat on the meat piece during processing by the second frame.

Stem Shaft

The stem shaft may be mounted on a sub-assembly that urges stem shaft lateral / translational movement along the stem shaft longitudinal length.

The stem shaft may be easily removed from the sub-assembly for cleaning. For example, the sub30 assembly may have a quick release mechanism to allow for tooless assembly and disassembly of the stem shaft in the apparatus.

The stem shaft may have a first end that engages an end of a bone in a meat piece. This stem shaft first end may be configured to have a special feature or features that encourage bone end and stem shaft mating and retention. This is described in further detail below.

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The stem shaft may have a second end that engages the sub-assembly. Engagement may be driving engagement to allow the sub-assembly to drive stem shaft movement.

The stem shaft may move reciprocally along stem shaft longitudinal axis. Reciprocal movement may be cyclic. For example, in one embodiment where the stem shaft longitudinal axis lies in a substantially 5 horizontal alignment, stem shaft movement may be leftwards along the shaft longitudinal axis during bone removal from a meat piece and subsequently rightwards to a home position. As rightward movement occurs, meat from the meat piece may be conveyed post bone removal from the bearing face in the central area to the second frame and, as the stem shaft moves into the tertiary area, the meat bears on the second frame and the stem shaft is withdraws from the meat.

The extent of leftward or rightward movement of the stem shaft may be governed by a stop or stops and/or governed by the stem shaft length.

Stem Shaft Rotation

The stem shaft may at least partly rotate about the stem shaft longitudinal axis during bone removal (leftward movement in the example above). Rotation may be governed by the sub-assembly that 15 controls axial movement of the stem shaft, for example by using a rotary actuator on the sub-assembly driving rotational movement. Rotation may be about a 90, or 120, or 150, or 180, or 210, or 240, or 270, or 300, or 330, or 360 degree rotation range. The rotation force may be up to 10, or 15, or 20, or 25, or 30, or 35, or 40, or 45, or 50Nm of torque.

Clamp Shaft

As noted above, the longitudinal axis of the clamp shaft may be axially aligned with the longitudinal axis of the stem shaft and may move laterally or translate along the clamp shaft longitudinal axis.

Optionally, the clamp shaft may rotate. Clamp shaft rotation may occur when driven by stem shaft rotation when the clamp shaft and stem shaft mate about a bone in a meat piece. Alternatively, rotational movement may be independently urged for example, via a rotational motor or driver acting on 25 the clamp shaft.

The clamp shaft may move reciprocally along clamp shaft longitudinal axis. The reciprocal movement may be cyclic for example, in one embodiment, where the clamp shaft longitudinal axis lies in a substantially horizontal alignment, the clamp shaft may move rightwards when actuated to engage a meat piece bone end. Once the meat piece bone ends are engaged between the clamp shaft and stem 30 shaft, the shafts together move leftwards during bone removal and, when the bone has been separated from the meat, the clamp shaft remains stationary in a home, left most position, while the stem shaft as noted earlier moves rightwards away from the clamp shaft. Clamp shaft movement rightwards to allow clamping of the meat piece bone and leftwards during bone removal may only commence when operator actuated - the clamp shaft may otherwise remain stationary in a home position fully leftwards 35 or in a stationary bone clamped position prior to bone removal.

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The extent of leftward or rightward movement of the clamp shaft may be governed by a stop or stops and/or governed by the clamp shaft length itself.

Shafts Axially Aligned and Shaft Movement

The shafts as noted may be axially aligned so that a first end of the clamp shaft and a first end of the stem shaft when moved laterally together along the common shaft axis could theoretically strike one another. The shafts share the same longitudinal axis. In reality, a stop or limit to movement may prevent the two ends from striking each other although prevention of striking is not essential.

The stem shaft and clamp shaft may have a substantially common cross-section diameter. The only variation in shape between the stem shaft and clamp shaft may be at the first ends of the stem shaft and clamp shaft. The common cross-section diameter may for example be approximately 30, or 35, or 40, or 45, or 50mm. Reference is made herein to 'diameter' and round shaped shafts however, as should be appreciated, the shafts need not have a round cross-section and could having semi-circular shapes, polygonal shapes or other specific protrusions.

Opening

One or both shafts may move through the at least one opening in the bearing face (in one embodiment, the bearing face being the first or second frames described above). In one embodiment, an opening may be located on a first left side of the central area corresponding to the first frame and/or bearing face that is configured to receive a bone and the clamp shaft therethrough to a secondary area. In a further embodiment, an opening may be located on a second or right side of the central area corresponding to the second frame that is configured to receive a stem shaft therethrough. At least one of the openings may act to guide and help align the shafts together.

The first frame opening may be sized to fit a meat piece bone and shaft diameter through the opening as the shaft(s) and bone are pushed from the meat and into the secondary area.

The second frame opening surrounds may have a bush that the stem shaft passes through. The bush may be a nylon bush. The bush may fully surround the stem shaft as it moves through the opening, the bush extending around the second frame opening circumference. The bush may be removed toolessly. Tooless removal may be useful to allow for easy servicing and cleaning of the apparatus and bush itself. The bush may further comprise at least one seal that abuts the stem shaft as the stem shaft moves through the bush (and aperture in the frame). The bush may substantially seal the central area of the apparats from the secondary or tertiary areas of the apparatus so that meat piece and meat movement is bound within the central area.

Shaft First Endings

The stem shaft first end may have a dual prong shape, the prongs configured to accept and conform in one embodiment to the hip end of a leg bone so that the region between a head and a greater trochanter of the leg bone nests between the prongs.

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The clamp shaft first end may have a dual prong shape, the prongs configured to accept and conform in one embodiment to the knee end of a leg bone so that a patellar surface between a medial condyle and a lateral condyle of the leg bone nests between the prongs.

The prongs may act as guides to help seat and retain the bone ends with the shafts.

The stem shaft and clamp shaft may initially be round in cross-section shape and transition to a flat prong shape.

The transition from a round shaft cross-section to the clamp shaft flat prong shape may be relatively sharp, defined by a shoulder. The shoulder or step may be approximately 90 degrees or orthogonal to the shaft longitudinal axis. That is, the shoulder transition of the clamp shaft is abrupt being at right angles to or very nearly at right angles to the clamp shaft longitudinal axis.

By contrast, for the stem shaft, the transition from a round shaft cross-section to the stem shaft flat prong shape may be comparatively gradual with no distinct shoulder like the clamp shaft, instead having a gradual tapering from the round stem shaft cross-section to the flat prong shape. The gradual tapering may be an angle (continuous or varying) of approximately 10, or 15, or 20, or 25, or 30, or 35, or 40, or

45 degrees relative to the shaft longitudinal axis.

The clamp shaft prongs may be relatively short. The opening between the clamp shaft prongs may be defined by a radius. The clamp shaft prong length may for example be approximately equivalent to around 10, or 15, or 20, or 25, or 30% of the overall clamp shaft diameter. In one embodiment, the clamp shaft prongs may be around 5, or 6, or 7, or 8, or 9, or 10, or 11, or 12, or 13, or 14, or 15mm long 20 and around 1, or 2, or 3, or 4, or 5, or 6, or 7, or 8mm wide. The radius between the prongs may be circular defining part of an arc and forming webbing between the prongs. The width of the webbing may be same as the width of the prongs or around 1, or 2, or 3, or 4, or 5, or 6, or 7, or 8mm wide. The webbing may step on each side immediately down towards to the clamp shaft with minimal if any chamfering or transition from the webbing external face to the webbing sides. As may be appreciated, this shape may be at least in part configured to conform with and retain at least part of a bone ending in the meat piece.

The prongs for the stem shaft may be relatively longer and thicker than the clamp shaft prongs. The opening between the prongs may also be defined by a radius. The stem shaft prong length may for example be approximately equivalent to around 20, or 25, or 30, or 35, or 40, or 45, or 50% of the overall 30 stem shaft diameter. In one embodiment, the stem shaft prongs may be around 10, or 15, or 20, or

25mm long and around 5, or 6, or 7, or 8, or 9, or 10, or 11, or 12, or 13, or 14, or 15mm wide. The radius between the prongs may be circular, defining part of an arc, and forming webbing between the stem shaft prongs. The radius may be around 15, or 20, or 25, or 30mm in diameter. The stem shaft prongs may be further defined by having a chamfer on one side of the radius between the prongs extending to the prong ends, the chamfer being configured to receive and seat a corresponding part spherical or part ovoid leg bone ending or extension. This chamfer may in one embodiment be an angle

2018203246 10 May 2018 of around 20, or 25, or 30, or 35, or 40 degrees relative to an orthogonal plane extending from the stem shaft axis, the chamfer having a wide opening and narrower ending e.g. an initial opening diameter of 20, or 21, or 22, or 23, or 24, or 25, or 26, or 27, or 28, or 29, or 30mm and narrowing to a smaller diameter of 15, or 16, or 17, or 18, or 19, or 20, or 21, or 22, or 23, or 24, or 25mm, the chamfer extending at least 20, or 25, or 30, or 35, or 40, or 45, or 50% into one side of the overall radius width.

The inventors have found that this particular shape of stem shaft first end may be important to allow the leg bone to be received and retained during processing, this shape conforming well to a variety of bone shapes and sizes thereby dealing well with natural variation in bone end shape and bone type.

Position and Fixing of the Meat Piece

To load a meat piece within the apparatus, the meat piece may be manually or automatically positioned within the central area of the apparatus and a first bone end in the meat piece aligned with the first end of the stem shaft. This may for example be a ball containing end of the bone to align with the first end of the stem shaft shape that is configured to accept a ball shape bone end.

During this stem shaft positioning step, the stem shaft may be located in a home position to the right 15 hand side of the apparatus, the stem shaft being predominantly in the tertiary area with only the first end or a part thereof of the stem shaft located in the central area. During meat piece positioning, the clamp shaft may be located away from the central area so as to allow easy access to the stem shaft. The clamp shaft may for example be located in a home position on the left hand side of the apparatus, at least predominantly in the secondary area of the apparatus.

Once the meat piece bone at one end is aligned with the stem shaft first end, the clamp shaft may be moved to have the clamp shaft first end mate with the opposing bone end in the meat piece. Movement of the clamp shaft may be lateral towards the stem shaft and the bone may then be gripped between the shaft first ends using a compression force between the shafts.

In one embodiment, the clamp shaft may be moved via at least one actuator laterally along the shaft axis 25 until the first end of the clamp shaft strikes the bone end.

Once the first end of each shaft meets with each end of a meat piece bone, the meat piece and bone inside may be securely held between the shafts. As should be appreciated, the bone inside the meat piece may be of a varying length and yet still securely held between the shafts since the degree of clamp shaft movement may be sufficiently large to accept and retain even the largest bone, and the degree of 30 lateral movement of the clamp shaft varied to suit the bone length. The apparatus therefore provides considerable versatility in length of bone and hence meat piece as well that may be processed.

Movement of the Shafts

Once the meat piece is secured as described above, the meat piece via the bone may be moved along the shaft common longitudinal axis laterally by having the shafts move in a synchronised and common 35 direction. During lateral / translational movement, the compression force on the bone between the

2018203246 10 May 2018 shaft first ends is maintained.

In completing lateral movement, the meat piece is moved to one side of the central area and eventually the meat is separated from the bone as the bone is pushed through the opening in the first frame or a part thereof.

As should be appreciated, this pushing movement is in one direction only - meat on the meat piece is not pushed in multiple/different directions during removal thereby leading to inconsistent meat removal, varied force loadings on the bone and/or varied force loadings on the shafts. Instead a pushing action in one direction occurs. The singular pushing action has been found by the inventors to be useful to avoid risk of bone breakage/fracture, and therefore minimise or avoid risk of potential contamination or downgrading of the meat piece through introduction of bone fragments into the meat.

Traditional manual techniques for bone removal rely on the user pulling the bone from the meat. Pulling creates a high tension load on the bone that can risk bone breakage/fracture during removal. If for example, the meat has not been sufficiently separated from the bone prior to pulling; the resulting tension load on the bone during bone removal can be even greater. The described pushing action (in one direction) utilised herein shifts the primary force loading from the bone to the meat and therefore from a brittle material (the bone) to the more compliant and malleable meat.

Cutting Assembly

As noted above, the apparatus may comprise a cutting assembly. The cutting assembly may both cut and subsequently lift the meat from the bone as the bone is pushed from the meat. This dual action may ensure cleaner separation and reduced force loadings on the bone and/or apparatus parts, particularly the shafts.

The cutting assembly may initially be disengaged from the meat piece or shafts during meat piece loading. Disengagement refers to the cutting assembly being located distal to the longitudinal axis of the shaft(s) and/or meat piece when the meat piece is loaded into the central area.

When shaft movement is actuated to cause bone removal from the meat piece, the cutting assembly may engage the meat piece about the clamp shaft first end and bone end and then travel along the bone length as the bone is pushed from the meat. When the cutting assembly reaches the bone end about the stem shaft first end, the cutting assembly may again disengage from the meat piece/bone end.

Engagement and disengagement of the cutting assembly may be automated. Automation may be based on a sensed position of the clamp shaft, stem shaft, meat piece, or bone. The sensed position may be based on a known point measured on the clamp shaft corresponding to the clamp shaft being in a position ready to receive or release the cutting assembly. The sensed position may be based on the meat piece position itself. As should be appreciated, the sensing methods and ways to achieve sensing and actuation may be varied.

The cutting assembly may in one embodiment comprise at least one jaw. The at least one jaw may

2018203246 10 May 2018 comprise a lip with an edge that travels along the interface between the meat and bone and the lip transitioning in direction from the edge to direct the cut meat away from the bone once the meat is cut.

The at least one jaw lip edge in cross-section may be positioned relative to the bone in a direction from approximately zero degrees (equivalent to being substantially aligned with the bone longitudinal axis), through to a position approximately 10, or 20, or 30, or 40, or 50, or 60, or 70, or 80 degrees offset relative to the bone longitudinal axis. The edge direction may for example be 10-70, or 20-60, or 30-50 or approximately 45 degrees offset relative to the bone longitudinal axis.

The at least one jaw lip in cross-section may curve or transition from the edge to a jaw body to a point where the jaw body lies substantially orthogonal to the bone longitudinal axis. The curve or transition 10 from the jaw edge to the jaw body may be sufficient to lift the meat away from the bone as bone and meat movement occurs.

The at least one jaw may have a squared edge and wherein one side of the squared edge, Rl, contacts the bone surface and the opposing side of the edge, R2, cuts the bone and meat interface. The at least one jaw edge width may be less than 5, or 4, or 3, or 2mm. As may be appreciated from the earlier 15 discussion around the angle at which the edge strikes the bone, where the edge strikes the bone at an angle, the actual orthogonal distance between the edge endings Rl and R2 may be less than the edge width, the edge angle reducing the orthogonal distance between points Rl and R2.

The at least one jaw when viewed front on, may be arcuate or rounded so as to conform to at least part of the circumference shape of a leg bone.

The cutting assembly may in one embodiment comprise two opposing semi-circular jaws biased together so as to at least partly encircle a bone during cutting. The jaws may move together with the bias, or apart against the bias, as the jaws travel along the bone longitudinal length movement with or against the bias governed by the bone diameter and shape. This ability to change the jaw opening allows the jaws to conform to the bone diameter and shape and account for natural shape variations. Whilst two opposing jaws are described, it should be appreciated that three, or four or more jaws may be used as well located about the bone and meat interface. Two opposing jaws may be useful however to optimise cutting assembly complexity and part cost yet still achieving a desired level of cutting.

The, or each, jaw may be formed as a separate part able to be removed and replaced from a wider cutting assembly frame or body. This may be useful to allow for greater apparatus versatility since the 30 jaw(s) themselves may take different sizes and shapes depending on the meat cut to be processed, for example to account for varying bone shape and size. The separate jaw parts may be attached to a cutting assembly bearing face or wider assembly via at least one fastener.

The area surrounding the at least one jaw in the cutting assembly may form the bearing face noted earlier. In this embodiment being a plate or plates about the at least one jaw that the meat may be 35 directed onto or bear against as the bone is pushed from the meat.

2018203246 10 May 2018

Eccentric Movement

In one embodiment, the cutting assembly or a part thereof may move at least partly about a plane eccentric to the shaft longitudinal axis. At least partial eccentric movement has been found by the inventors to be desirable to allow at least part of the cutting assembly and in particular, the at least one jaw or jaw edge, to follow changes in orientation of the leg bone elongated axis relative to the shaft longitudinal axis. As may be appreciated, animal bones may vary in eccentricity relative to a central longitudinal axis - a leg bone for example is typically slightly rounded so that the bone central axis may be offset at a points or points along the bone length relative to a purely straight axis from leg bone end to end. This eccentricity means that a cutting assembly that does not compensate for variation in bone 10 shape needs to be set to have a larger diameter of cutting to compensate for the bone shape variation (leading to a lower yield) or risk meat contamination by cutting into the bone at extremes of bone shape variation (leading to downgrading of meat value). Eccentric movement of the cutting assembly described herein or eccentric movement of at least the jaws of the cutting assembly allows the cutting assembly and/or jaws to follow and conform to the bone shape irrespective of the bone shape and loading orientation between the stem shaft and clamp shaft and hence allowing the cutting assembly or part thereof to be at an optimal point between the bone and meat interface yet avoid risking cutting into the bone itself.

In one embodiment, the cutting assembly or a part thereof, about the jaw and bone interface, may have up to 360 degrees of freedom of movement in the eccentric plane relative to the shaft longitudinal axis.

That is, the cutting assembly may have multiple degrees of freedom movement to allow at least part of the cutting assembly to follow bone contours irrespective of the shaft longitudinal axis position.

The extent of eccentric plane movement may be limited by a stop or by a limit to the mechanism or mechanisms providing the movement. In one embodiment, the extent of eccentric movement may be limited to less than 20, or 19, or 18, or 17, or 16, or 15, or 14, orl3, or 12, or 11, or 10mm relative to the 25 shaft longitudinal axis. The inventors have found that this limit may be sufficient to compensate for angular bone shape variations, a potentially more important feature being the ability to move the cutting assembly or a part thereof in an eccentric plane as opposed to the extent of eccentric movement.

As may be appreciated, the extent of variation may not be hugely significant but the direction of variation of angle along the bone length may be quite variable along an individual bone length as well as 30 between different animals and different meat pieces and cuts. The ability of the cutting assembly or part thereof to adjust to cater for bone shape variations make the described apparatus highly versatile and efficient at achieving high meat yield and avoiding risk of bone cutting and meat contamination or product downgrade.

Eccentric movement may in one embodiment be achieved using two pivot points in the eccentric plane 35 of movement. A first pivot point may allow substantially side to side pivoting movement of the cutting assembly at least one jaw while the second pivot point may allow substantially up or down pivoting

2018203246 10 May 2018 movement of the cutting assembly at least one jaw. In both cases, the pivot points referred to may be offset from the at least one jaw so as to increase the extent of eccentric movement possible about the shaft longitudinal axis.

In one particular embodiment, the jaws may be two opposing jaws that may be biased together about the bone cross-section as described above.

The two opposing jaws may be biased together via a scissor assembly to have the two jaws pivot together about a pivot axis off set from the point at which the jaws meet together. The bias action may be sprung driven, hydraulic driven or pneumatic driven to deliver a desired level of force urging the jaws together but not so much force as to cause the jaws to cut into the bone itself. The extent of jaw opening may be governed by the travel of the bias action and/or restrained by a plate or frame that the cutting assembly lies and/or travels within. As may be appreciated, the scissor assembly described may provide a first up/down travel pivoting movement eccentric to the shaft longitudinal axis.

The two opposing jaws as noted above may also have pivoting movement from side to side. This may be achieved by having the scissor assembly and/or jaws thereon mounted on at least one hanger, the hanger linking the scissor pivot point to a further pivot point distal to (typically above) the scissor pivot point. This hanger arrangement allows the jaws to move from side to side as well about the hanger pivot point thereby extending the range of eccentric movement possible.

As may be further appreciated, the cutting assembly may have a load force applied in a direction parallel to the shaft longitudinal axis as the bone is pushed from the meat piece during processing - expressed in 20 terms of meat piece movement, the meat strikes a bearing face on the cutting assembly or a part thereof in the direction of the shaft longitudinal axis during bone pushing. To restrain cutting assembly movement in a direction parallel to the shaft longitudinal axis, the cutting assembly or a part thereof may be located and bear against a plate or move between opposing plates, the plate(s) optionally fixed in place. For example, the cutting assembly may bear against the first plate noted above. In one embodiment two opposing plates may be used with the cutting assembly located between a gap in the plates and the cutting assembly is free to move in an eccentric plane relative to the shaft axis within the gap however, the plate or plates prevent parallel movement of the cutting assembly or a part thereof with the shafts along the shaft longitudinal axis. In this embodiment, the first plate may form one side of the gap while a further plate may form the opposing side of the gap.

In one embodiment, the cutting assembly or a part thereof may comprise bearings or other friction lowering parts or construction to allow ease of movement of the cutting assembly against a plate about the eccentric plane of movement. In one embodiment, the bearings may be ball bearings located about the interface between the plate or plates and cutting assembly or part thereof so as to distribute a bearing face load about the plate/cutting assembly interface. Other friction lowering methods may be used as well such as selection of low friction materials for the interface, use of roller bearings and so on.

The bearings or other friction lowering parts or construction may be on the cutting assembly load

2018203246 10 May 2018 bearing face only, the load bearing face being the cutting assembly face that bears on a plate when bone pushing occurs.

Meat and Bone Interaction

As may be appreciated, the apparatus and method described herein may be used to separate a bone or bones from meat on a meat piece to therefore prepare the meat piece either for sale in the bone removed form or for further processing into further cuts. After bone removal, the meat may substantially retain its connectivity so that a hollow remains within the mass of meat where the bone has been removed.

In one embodiment, the meat piece is a leg. The leg may be a leg from a lamb.

Prior Processing

Before loading of the meat piece into the apparatus described, some initial processing may be completed. This initial processing may be completed by hand although extra automated processing could be completed to further automate the whole process. Initial processing envisaged currently may comprise removal of ancillary bones about the main bone to be removed - in the case of a leg of lamb;

this might mean removal of the aitch bone and shank. Some trimming to expose the bone ends may also be completed. What is avoided though is the need to trim and scrape down the bone or tunnel through the meat/bone interface as might be completed in traditional hand tunnel boning operation.

Yield

In terms of meat processing, yield refers to the amount of meat recovered from an animal carcass or cut thereof. With respect to the meat piece described herein, and specifically processing of a lamb leg, the inventors have found that the meat yield achieved via the described apparatus is very favourable and consistent. This consistency is achieved even in long processing runs where hundreds or even thousands of lamb legs may be processed in a single processing run. In terms of figures, if the best possible meat yield from the meat piece were 100% corresponding to all meat removed from the bone, then the apparatus and method described herein, in the inventor's experience, achieves a yield of at least 95, or 96, or 97, or 98, or 99, or 100%. That is, more or less complete meat removal is achieved from a bone repetitively over hundreds or even thousands of meat pieces during a processing run.

Speed of Processing

As should be appreciated, the speed of processing possible using the apparatus described may be considerably greater than that of art manual cutting and tunnel boning. Based on the inventors work to date, processing speeds of up to one meat piece per 0.5 to 1 minute should be readily possible. At present, the speed of processing is in part limited by the time it takes to load a meat piece in the apparatus. If this loading process were automated, such as with a robotic arm, the processing speed may be reduced even further.

Safety

2018203246 10 May 2018

Health and safety issues may also be addressed by use of the apparatus and method described. For example, the step of bone removal by actuating shaft movement cannot occur until the meat piece is locked in place between the shafts. As a further safety precaution, shaft movement to cause bone removal may be restricted until a shroud is closed over the central area thereby restricting operator access to the moving parts during tunnel boning.

The one time the operator may be required to access the central area is to load the meat piece between the shafts. Loading at the stem shaft end may be performed while the shafts are stationary. Movement of the clamp shaft may only occur once the operator actuates the clamp shaft movement and, the speed of clamp shaft movement and extent of movement may be carefully governed so as to allow time for the 10 operator to position the meat piece/bone relative to the clamp shaft and, by limiting the extent of movement, the clamp shaft may never get close to where the operator holds the meat piece during positioning. This method of operation may therefore prevent risk of crushing or interference between the operator and clamp shaft movement or other part movement.

Automated Transfer and Minimising Handling

As may be appreciated from the above description, when the bone is pushed from the meat, the bone may be moved to a secondary area. When the stem shaft returns to a home position primarily in the tertiary area with only the stem shaft end within the working area, compression of the bone between the shafts stops and the bone is released from the shaft first ends.

In one embodiment, a chute may be located below the apparatus secondary area to receive and collect 20 the bone as it drops via gravity from the shaft first ends. A conveyer may receive the bone from the chute and convey the bone away from the apparatus. Similarly, as the stem shaft returns to a home position, the stem shaft may be withdrawn from the meat. As this occurs the meat is released from the first end of the stem shaft. A chute may be located below the apparatus central area to receive and collect the meat as it drops via gravity on release from the stem shaft. A conveyer may receive the meat 25 from the chute and convey the meat away from the apparatus.

Materials

The materials used to form the apparatus may all be food safe or food grade materials that are able to be cleaned and re-used on a regular basis and which present a low risk of microbial or other contamination. Materials envisaged to manufacture the apparatus may for example be stainless steel 30 and, for the bush(es), nylon may be an appropriate material. Other materials may be used beyond stainless steel or nylon and reference to these materials should not be seen as limiting.

Advantages

The apparatus described has a variety of advantages over both manual and art automated apparatus and methods of tunnel boning. Selected advantages may comprise:

- The shaft first ends are configured to engage and conform to the bone end shapes hence

2018203246 10 May 2018 provide a strong retaining force to hold the bone during meat removal.

- Leg bone shape irregularities are addressed through movement of the cutting assembly or a part thereof during bone removal;

- A consistent singular load force may be applied to the meat piece bone during bone removal leading to lower risk of apparatus damage or meat contamination;

- Bone pushing in one direction as opposed to bone pulling leads to reduced risk of bone fracture;

- The apparatus has a high and consistent meat yield and low/no risk of contamination or meat downgrade through incomplete bone removal;

- The apparatus may cater for varying bone length and diameter.

The embodiments described above may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features.

Further, where specific integers are mentioned herein which have known equivalents in the art to which the embodiments relate, such known equivalents are deemed to be incorporated herein as of individually set forth.

WORKING EXAMPLES

The above described tunnel boning apparatus and method of tunnel boning are now described by reference to specific examples.

EXAMPLE 1

By way of context and as a preamble to discussion of an embodiment of the apparatus and method described herein, a meat piece 100 and characteristics of a bone 101 therein is described. Figure 1 shows a leg bone 101 from a lamb with the meat 102 (not shown) surrounding the bone 101 to form the meat piece 100 removed for ease of viewing and discussion.

The bone 101 generally shown by arrow 101 comprises bone 101 ends indicated by arrows 103, 104.

One end 103 of the bone 101 corresponds to the hip end 103 of the bone 101. At this hip end 103 the bone 101 has a region 105 between the head (ball) 106 and great trochanter 107 of the bone 101. This region 105 provides a natural seat for the stem shaft (see later discussion).

The opposing end 104 of the bone 101 corresponds to a knee end 104 of the bone 101. At this end 104, there is a patellar surface 108 between the medial condyle 109 and lateral condyle 110 of the bone 101. This patellar surface 108 may provide a natural seat for the clamp shaft (see later discussion).

Turning to Figures 2 to 16, an embodiment of the tunnel boning apparatus and details thereof are illustrated, the apparatus as whole generally indicated by arrow 1 is illustrated. The apparatus 1 is a

2018203246 10 May 2018 modular unit comprising an open side with a central area 2 between two frames 3 and 4 on either side. A secondary area 5 is located to the left of the central area 2 and a tertiary area 6 is located to the right of the central area 2 in the Figures shown.

Translating between the different areas 2, 5 and 6, are a pair of shafts 7, 8.

A stem shaft 7 may be located on the right hand side of the apparatus 1, the stem shaft 7 at a first end 9 mating with the hip end 103 of a bone 101 and having an opposing stem shaft 7 end 10 linked to a subassembly 11. The stem shaft 7 may be releasable from the sub-assembly 11 for example for cleaning removal. The sub-assembly 11 may actuate movement of the stem shaft 7 either via translation along the shaft axis AA or rotationally about the shaft axis AA. The stem shaft 7 may, in a home position, be stationary extending from the sub-assembly 11 through the tertiary area 6 and through an opening 12 in the right hand frame 4 so that at least part of the stem shaft 7 first end 9 is located inside the central area 2 ready for meat piece 100 engagement. The stem shaft 7, when actuated, moves via translation along the stem shaft 7 longitudinal axis AA leftwards or rightwards i.e. in a reciprocal or cyclical manner, the direction of motion depending on the processing step. The stem shaft 7 movement is described in more detail below. The stem shaft 7 may move through a bush 70 located about the frame 4 opening

12. The bush 70 may be made from a low friction material such as nylon and acts to locate the stem shaft 7 as it moves relative to the frame 4 and seal the central area 2 from the tertiary area 6 as the stem shaft 7 moves axially through the frame 4 opening 12. The bush 70 may be removable for cleaning. The stem shaft 7 at the first end 9 has a shape that confirms to and retains the bone 101 end 103. As shown in the Figures, the stem shaft 7 first end 9 has two prongs 30, 31 that extend from a rounded body 32 of the stem shaft 7. The stem shaft 7 transitions relatively gradually from the rounded body 32 to the flat prongs 30, 31 defining an opening 33 between the prongs 30, 31 that may be defined by a radius. The stem shaft 7 prong 30, 31 length may be approximately 10-25mm long and around 5-15mm wide. The radius of the prong opening 33 between the prongs 30, 31 may be circular, defining part of an arc, and forming webbing between the stem shaft 7 prongs 30, 31. The radius may be around 15-30mm in diameter. The stem shaft 7 prongs 30,31 may be further defined by having a chamfer 34 on one side of the opening 33 between the prongs 30,31 extending to the prong 30,31 ends, the chamfer 34 being configured to receive and seat a corresponding part spherical or part ovoid leg bone 101 end 103, in particular the region 105 between the head (ball) 106 and great trochanter 107 of the bone 101. This chamfer 34 may be at an angle of around 20-40 degrees relative to an orthogonal plane extending from the stem shaft 7 axis AA, the chamfer having a wide opening and narrower ending, the chamfer 34 extending 20-50% into one side of the overall opening 33 width.

The clamp shaft 8 may be located on the left hand side of the apparatus 1, the clamp shaft 8 at a first end 13 mating with the knee end 104 of a bone 101 and having an opposing clamp shaft 8 end 14 linked to a mount 15 such as an alternate side of the sub-assembly 11. The clamp shaft 8 may, in a home position, be stationary extending from the mount 15 into the secondary area 5. The clamp shaft 8 when actuated moves via translation along the clamp shaft 8 longitudinal axis AA (same axis as the stem shaft

2018203246 10 May 2018

7) leftwards or rightwards i.e. in a reciprocal or cyclical manner, the direction of motion depending on the processing step. The clamp shaft 8 movement is described in more detail below. The clamp shaft 8 may have prongs 40, 41, the prongs 40,41 being relatively short compared to the stem shaft 7 prongs 30, 31. The prong opening 42 between the clamp shaft 8 prongs 40, 41 may be defined by a radius. The clamp shaft 8 prong 40, 41 length may be approximately 5-15mm long and around l-8mm wide. The prong opening 42 between the prongs 40, 41 may be circular defining part of an arc and forming webbing between the prongs 40, 41. The width of the prong opening 42 may be same as the width of the prongs 40, 41. The prong opening 42 steps immediately down towards to the clamp shaft 8 with minimal if any chamfering or transition. This clamp shaft 8 end 13 shape conforms with and retains the 10 knee end 104 of a bone 101, the prong opening 42 receiving the patellar surface 108 of the bone 101.

The apparatus 1 further comprises a cutting assembly 50. The cutting assembly may comprise a scissor assembly 51 made up of two arms 52, 53 and with opposing jaws 54, 55 on the arms 52, 53 offset from a scissor assembly 51 pivot point 56a. The cutting assembly 50 is largely aligned in an orthogonal plane relative to the shaft axis AA. The cutting assembly 50 further comprises a bias 57 to open and close the 15 jaws 54, 55 about the pivot point 56a. The cutting assembly 50 may also comprises a hanger 57 in the form of an elongated rod, the hanger 57 linking the scissor assembly 51 to a point on the frame 3 providing a further pivot point 56b. Rods 58 may extend from the arm 52, 53 endings parallel to the shaft axis AA and through an opening in the frame 3. The scissor assembly 51 arms 52, 53 may provide a bearing face or region shown with arrow 59 that meat 102 from a meat piece 100 may bear against during tunnel boning. The way the cutting assembly 50 operates and moves is described further below.

The cutting assembly 50 jaws 54, 55 may have a semi-circular shape when viewed front on as would be presented to a meat piece 100, the two jaws 54, 55 when closed forming a circle. Each jaw 54, 55 may have a lip indicated by arrow 60, the lip 60 comprising an edge 61 and a transition region 62, the transition region 62 leading to a surrounding jaw body 63. The lip 60 edge 61 in cross-section is positioned relative to the bone 101 in a direction from approximately zero degrees (equivalent to being substantially aligned with the bone 101 longitudinal axis), through to a position approximately 10-80 degrees offset relative to the bone 101 longitudinal axis. The jaw 54, 55 body 63 may be substantially orthogonal to the shaft axis AA. The edge 61 has a squared end with one side R1 of the edge 61, contacting the bone 101 surface and the opposing side R2 of the edge 61, cuts the bone 101 and meat

102 interface. A further aspect of the cutting assembly 50 may be the ability of the cutting assembly 50 and in particular, the jaws 54, 55, to move in an eccentric plane BB relative to the shaft axis AA independent of other parts of the apparatus 1 so as to follow the contours and shape of a bone 101 between the jaws 54, 55. The pivot points 56a, 56b noted above allow the jaws 54, 55 to move within an eccentric plane BB. To assist with eccentric plane BB movement, the scissor assembly 51 may move about the frame 3 face via ball bearings 64 embedded in the scissor assembly 51 arms 52, 53 that bear on the frame 3 face. The ball bearings 64 also help transfer an axial load imposed on the cutting assembly 50 by meat 102 bearing on the cutting assembly 50 or a part thereof e.g. the scissor assembly 51 arms 52, 53, the axial load being transferred to the frame 3.

2018203246 10 May 2018

Turning to the method of operation and referring to Figures 17 to 22, the apparatus 1 starts a processing cycle with each shaft 7, 8 in a home position as described above, the stem shaft 7 to the right of the apparatus 1 with only the first end 9 within the central area 2 and the clamp shaft 8 to the left of the apparatus 1 in the secondary area 5. The meat piece 100 is moved into the central area 2 of the apparatus 1 and the hip end 103 of the meat piece 100 bone 101 is aligned with the first end 9 of the stem shaft 7, the region 105 between the head (ball) 106 and greater trochanter 107 seated against the opening 33 between the stem shaft 7 prongs 30, 31. This step may be completed manually by a person lifting the position the meat piece 100 or automatically using for example a robot arm.

Once positioned, the clamp shaft 8 may be moved (rightwards in this example) so that the first end 13 of the clamp shaft 8 enters the apparatus 1 central area 2 moving along the shaft axis AA and engages the opposing knee end 104 of the meat piece 100 bone 101. The prong opening 42 between the prongs 40, 41 on the first end 13 of the clamp shaft 8 may seat the bone 101 end 104 patellar surface 108 between the medial condyle 109 and the lateral condyle 110. The bone 101 inside the meat piece 100 is then held between the shafts 7, 8 by compression force along shaft axis AA and the first ends 9, 13 of each shaft 7,

8.

Synchronised shaft 7, 8 axial movement leftwards or towards the secondary area 5 may then occur, the compression force being maintained on the bone 101 inside the meat piece 100. When the meat piece 100 is conveyed to the right, the cutting assembly 50 senses shaft 7, 8 axial movement and engages with the clamp shaft first end about the bone 101 knee end 104. Engagement refers to the cutting assembly

50 jaws 54, 55 closing about the bone 101 circumference, closing being governed by the bias 57. Prior to engagement, the cutting assembly 50 may be located away from the shaft axis AA. Once engaged, the jaws 54, 55 then travel along the bone 101 and meat 102 interface as shaft 7, 8 axial movement occurs. During axial movement, the meat 102 is cut by the jaw 54, 55 edge 61 and then, as the meat 102 moves axially, the meat 102 travels over the jaw 54, 55 transition region 62 and bears on the jaw 54, 55 body 63 or scissor assembly 51 bearing face 59. During cutting assembly 50 jaw 54, 55 movement along the bone 101, the jaws 54, 55 may move in an eccentric plane BB relative to the shaft axis AA allowing the jaws 54, 55 to follow any eccentricity in the bone 101 length relative to the bone 101 end 103 to end 104 axis. During this cutting stage, the stem shaft 7 (or optionally the clamp shaft 8) may be rotated about the shaft axis AA to further assist with cutting and lifting described above.

As the bone 101 is moved axially along the shaft axis AA, the bone 101 is effectively pushed from the meat 102, the bone 101 between the shafts 7, 8 being pushed into the secondary area 5 through an opening in the left frame 3. Axial shaft 7, 8 translation continues until the bone 101 has fully entered the secondary area 5 and the meat 102 is fully removed from the bone 101. At this point the meat rests on the stem shaft 7 while the bone is held between the shaft 7, 8 first ends 9, 13 in the secondary area 5.

Axial translation stops at this point, typically corresponding to a point of maximum travel or thereabouts of the shafts 7, 8 leftwards. As may be appreciated, this position once reached may be the home position of the clamp shaft 8. The processing cycle continues with the stem shaft 7 move via axial

2018203246 10 May 2018 translation in a reverse direction (rightwards) while the clamp shaft 8 remains stationary. When this occurs, a compression force on the bone stops and the bone through gravity may drop away from the shaft 7, 8 first ends 9, 13 for example into a chute 200 below the secondary area 5 to be collected or transported away for further processing as may be desired. Reverse axial movement of the stem shaft 7 5 carries the meat 102 with the stem shaft until the meat 102 bears against the opposing right frame 4 of the central area 2. When this occurs, the meat 102 remains stationary as the stem shaft 7 withdraws from the meat 102, the stem shaft 7 continuing axially into the tertiary area 6. When the stem shaft 7 reaches the home position again, insufficient shaft 7 length remains in the central area 2 to hold the meat 102 and the meat 102 drops by gravity from the stem shaft 7. The meat 102 may be collected via a 10 chute 300 below the central area 2 and conveyed away for further processing as may be desired. AT this point the operating cycle is complete.

Aspects of the tunnel boning apparatus and method of tunnel boning have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the claims herein.

Claims (21)

1. WHAT IS CLAIMED IS:

   1. A tunnel boning apparatus comprising:

   a bearing face;

   an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends; and;

   when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face while the meat bears against the bearing face surrounding at least part of the opening and is removed from the bone as the bone is pushed through the bearing face opening.
2. 2. A tunnel boning apparatus comprising:

   a bearing face;

   an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

   a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the opening, meat on the meat piece is cut and subsequently lifted from the bone by the cutting assembly or a part thereof.
3. 3. A tunnel boning apparatus comprising:

   a bearing face;

   an axially aligned stem shaft and clamp shaft, the shafts configured to travel through an opening in the bearing face or a part thereof, a first end of each shaft configured to retain opposing ends of a bone in a meat piece between the first ends;

   a cutting assembly; and when a meat piece is positioned and fixed between the shaft first ends and movement of the shafts relative to the bearing face actuated, the shafts move in a synchronised and common direction so

   2018203246 10 May 2018 that the bone is pushed through the opening in the bearing face and, as the bone is pushed through the opening, the cutting assembly or a part thereof moves at least partly about a plane eccentric to the shaft longitudinal movement axis.
4. 4. A tunnel boning apparatus comprising:

   An axially aligned stem shaft and clamp shaft, the shafts configured to retain opposing ends of a bone in a meat piece between the first ends;

   wherein the stem shaft comprises a first end with a dual prong shape, the prongs configured to accept and conform to a hip end of a leg bone so that the region between a head and a greater trochanter of the leg bone nests between the prongs; and wherein the clamp shaft comprises a first end with a dual prong shape, the prongs configured to accept and conform to the knee end of a leg bone so that a patellar surface between a medial condyle and a lateral condyle of the leg bone nests between the prongs.
5. 5. The apparatus as claimed in any one of the above claims wherein the apparatus comprises a central area framed on either side by first and second frames, this central area being where the meat piece is loaded between the shafts and, post bone removal, where the meat piece may drop from.
6. 6. The apparatus as claimed in claim5 wherein to one side of the central area is a secondary area where the bone is pushed to and which lies behind a first frame.
7. 7. The apparatus as claimed in claim5 or claim 6 wherein a further tertiary area is positioned opposite the first plate defining the opposing side of the central area.
8. 8. The apparatus as claimed in any one of the above claims wherein the stem shaft moves reciprocally in a common cycle of movement along a stem shaft longitudinal axis.
9. 9. The apparatus as claimed in any one of the above claims wherein the stem shaft at least partly rotates about the stem shaft longitudinal axis during bone removal.
10. 10. The apparatus as claimed in any one of the above claims wherein the longitudinal axis of the clamp shaft is axially aligned with the longitudinal axis of the stem shaft and wherein the clamp shaft

    2018203246 10 May 2018 moves laterally or translates along the shaft longitudinal axis.
11. 11. The apparatus as claimed in any one of the above claims wherein one or both shafts move through the at least one opening in the bearing face.
12. 12. The apparatus as claimed in any one of the above claims wherein the bearing face is in the first or second frames.
13. 13. The apparatus as claimed in claim 5 wherein an opening is located on a first side of the central area corresponding to the first frame and/or bearing face that is configured to receive a bone and the clamp shaft therethrough to the secondary area.
14. 14. The apparatus as claimed in claim 5 wherein an opening is located on a second or right side of the central area corresponding to the second frame that is configured to receive the stem shaft therethrough.
15. 15. The apparatus as claimed in any one of the above claims wherein the stem shaft first end has a dual prong shape, the prongs configured to accept and conform to the hip end of a leg bone so that the region between a head and a greater trochanter of the leg bone nests between the prongs.
16. 16. The apparatus as claimed in any one of the above claims wherein the clamp shaft first end has a dual prong shape, the prongs configured to accept and conform in one embodiment to the knee end of a leg bone so that a patellar surface between a medial condyle and a lateral condyle of the leg bone nests between the prongs.
17. 17. The apparatus as claimed in any one of the above claims wherein the apparatus further comprises a cutting assembly that both cuts and subsequently lifts the meat from the bone as the bone is pushed from the meat.
18. 18. The apparatus as claimed in claim 17 wherein the cutting assembly comprises at least one jaw with a lip, the lip having an edge that travels along the interface between the meat and bone and the lip transitioning in direction from the edge to direct the cut meat away from the bone once the meat is cut.

    2018203246 10 May 2018
19. 19. The apparatus as claimed in claim 17 or claim 18 wherein the cutting assembly or a part thereof moves at least partly about a plane eccentric to the shaft longitudinal axis during cutting to follow changes in orientation of the leg bone elongated axis relative to the shaft longitudinal axis.
20. 20. The apparatus as claimed in any one of claims 17 to 19 wherein the meat on the meat piece bears against at least part of the cutting assembly during bone removal.
21. 21. A method of tunnel boning a meat piece, the method comprising the steps of:

    selecting an apparatus as claimed in any one of the above claims;

    positioning the meat piece and bone therein between each shaft first end;

    actuating synchronised shaft axial movement so that the meat piece bone is pushed from the meat piece meat.