GB2150416A - Boning of meat - Google Patents

Abstract

A tool for boning meat includes an applicator and cutter, the cutter being an elongate flexible element with repeatedly changing cross-section and the applicator being formed to co-operate with a bone end to, in operation, pass a loop of the cutter from around the applicator to around the bone, the tool including means to drive the cutter lengthwise to cut along and round the bone. The cross-section may change in only shape or only area or both shape and area. For example, cutter 3 has spaced projections, and may be a monofilament knotted at intervals. It is driven by pulley 2 operable by a flexible drive (8) and is placed in position on the bone by tubular applicator 5. <IMAGE>

Description

SPECIFICATION Boning of meat This invention relates to the removal of bone from an animal carcase.

In the processing of meat the removal of the bones from a carcase is a significant preliminary step. The meat is strongly attached to the bone and removal by hand methods with a sharp knife requires a skilled operator if waste is to be avoided either by removing too much with the bone or by leaving bone in the meat. Also the handling of raw carcases is best kept to a minimum for the health of the operator and the cleanliness of the product.

It is an object of the invention to provide an improved technique for boning meat.

According to the invention there is provided a tool for boning meat including a cutter and an applicator, the cutter being an elongate flexible element with repeatedly changing cross-section and the applicator formed to co-operate with a bone end to, in operation, pass a loop of the cutter from around the applicator to around the bone, the tool including means to drive the cutter lengthwise to cut along and round the bone.

The cross-section can be changed in at least one of shape and area. The shape change in cross-section may be produced by turning one part of the cutter with respect to an adjacent part, as in a chain of links, and not produce significant, if any, change in area.

The area change in cross-section may be produced by enlarging the cutter at intervals along it, for example a knobbly string.

Conveniently the cutter is a length of nylon monofilament knotted at intervals of about 5 mm to 30 mm and the applicator is a sharp-ended tube or gouge providing a smooth outer surface for the moving driven cutter to slip along and engage around the bone. The cutter may be driven in one direction continuously or reciprocated.

According to an aspect of the invention there is provided an automatic meat deboning apparatus including a tool of cutter and applicator described above, means to secure a carcase or part thereof, means to examine the carcase to determine the position of a bone end, means to place the cutter around the applicator and to drive the cutter, means to position the applicator over the bone end, means to move the driven cutter off the applicator and around the bone to cut the bone from the meat, means to determine the end of the cutting out of a bone and disengage the cutter.

According to another aspect of the invention there is provided a method of taking meat off a bone including causing a succession of impacts at the junction of the meat and the bone, cutting the meat without affecting the bone.

Embodiments of the invention will now be described with reference to the accompanying drawings in which: Figure 1 shows two views of tool embodying the invention; Figure 2 shows stages in the use of a tool such as is shown in Figure 1 and in accordance with the invention; The tool shown in front elevation in Figure 1 a and side elevation in Figure 1 b includes a housing 1 which supports a drive pulley 2 and surrounds a cutter 3 allowing part of the cutter 4 to project from the housing at the end opposite the pulley. The pulley 2 is operable by suitable means, e.g. a flexible drive 8 from a power source, not shown, to drive the cutter. The housing may include guides, not shown, to constrain the cutter to a chosen path. The drive may be arranged to produce a unidirectional reciprocating motion of the cutter.

The cutter in the illustrated embodiment is an elongate flexible element with spaced projections and can be formed in various ways. One convenient form is to make knots in a nylon (RTM) or other plastics monofilament at intervals. The cutting line of the cord type of rotary grass cutter may be a suitable monofilament. The knots can be at intervals of between 5 mm and 30 mm for the cutting out of rib bones from a bacon carcase. Other sizes of monofilament and knot spacing may be used for other applications.

Other forms of cutter can be ball chain or links joined together in the manner of a chain saw cutter or thin and thick beads placed alternately on a cord or wire. The exact construction can be varied to produce the required form of cutter having a respectively changing cross-section and of generally blunt or smooth nature. The blunt or smooth nature of the cutter including the projections, when driven at a suitable speed, produces a cutter with a cutting action which has adequate energy to sever meat from the bone by the impact of the projections but neither sufficient energy nor sharp enough surface to cut into the bone. This produces good separation without the risk of bone pieces in the separated meat or undue loss of meat with the bone. The material of the cutter must be suitable for food processing, e.g.

a food-quality plastic or stainless steel.

The pulley 2 may be smooth or may be formed to engage the projections of the cutter as appropriate to achieve adequate drive connection. The pulley may be of spring-loaded halves to cope with overloads.

The tool also includes an applicator 5 by which, in operation, the cutter is placed in position around a bone. In Figures la and l b the applicator 5 is shown as a tube, of metal or other hard material, having a smooth outer surface to allow the cutter to run easily over it. One end, 6, of the applicator is sharp and shaped somewhat as is a gouge to enable the applicator to be pushed over the end of a bone, such as a rib. Other shapes and forms, and material, may be used to achieve the function of the applicator.

In use of the tool the cutter is driven at a suitable speed and the tool placed near to the end of the bone to be released from the meat. The applicator is placed in the loop 4, as shown in Figure 1, and pushed onto the end of a bone, if necessary cutting into the meat around the bone with the sharp edge 6.

The driven cutter is then moved along the applicator and off onto the bone. The applicator can be retracted or left as convenient. The driven cutter loop is pulled tightly around the bone and cuts the meat away from the bone as it is drawn along the bone to cut it free from the rest of the carcase.

The operation can be controlled manually or made automatic to a required degree.

For the basic manual operation the cutter may be stopped and started and held at suitable angles during the deboning action and the placing of the applicator on the bone-end will be under the guidance of the operator. The applictor may even be a separate hand-held component and the housing 1 may have a handle by which the operator guides the cutter. The handle may control the stopping and starting of the cutter by a suitable linkage or electrical connection to say a clutch or startistop control of a motor.

For an automatic operation both the applicator and cutter will require some form of automatic control. It will generally also be necessary to determine the position of the bone end and the finish of the cutting-out of the bone. Various techniques for detecting the position of the bone are available. For example an array of needles may be used to probe the carcase and detect the position of the bone-end by the relative displacement of some of the needles.

This displacement, when sensed, is converted to instructions for means to move the applicator into position on the bone-end and thereby bring the cutter, moved with the applicator, into position to release the bone. The completion of bone release can be detected, for example by the lessening of the load on the cutter, and the cycle restarted for the next bone. The probing can be carried out for the next bone while one is being cut-out. The bone can be cut-out completely or left partly connected, at say the vertebrae end, to be separated by a distinct cutting action.

The cutter can take other forms. Instead of having a cross-section area repeatedly increased and decreased, as above with the "knobbly string" construction, the shape of the cross-section may change, even without change in area. For example a chain of links can be used with each successive link in a plane at an angle to the previous one. The angle is usually 900 but need not be. In one embodiment the links are of metal and about 10 mm long.

In designing the cutter the aim is to hit the meat with repeated impacts sufficient to cut the meat away from the bone without affecting the bone, e.g.

chipping or scoring it. The size and shape of the change in cutter cross-section, and the speed of the cutter is made fast enough to do this without being too fast, causing meat to be torn out and thrown around.

The exact form of the tool and any associated drive and control equipment can be varied to suit the intended use. Figure 2 shown in Figures 2a, 2b and 2cthree stages in the deboning of a bacon back ready for slicing. The bacon back, 21, shown in end view contains rib bones, 22, just beneath one surface under a thin layer of tissue. The ends, cut at an earlier stage, lie exposed at one surface flush with the surface. The applictor 5 is moved up to the end of a bone 22 with the cutter 3 in place around the applicator, Figure 2a. In Figure 2b the driven cutter has been transferred from the applicator to around the bone 22 via an undercut 24 made by edge 6 of the applicator. The angle of the cutter to the bone is generally not critical and can be chosen to give forward action as well if required.The speed of the cutter can be constant or even varied with load if required. Initial tests have shown speeds of 3 to 5 metrelsecond to be suitable for bacon. However other speeds may be suitable especially for different applications. The applicator can be left in position, the cut-away 7 allowing the bone end to be released, or the applicator can be withdrawn in suitable manner or even allowed to ride on the bone as it has no part at this stage. Figure 2c shows the ending of the release of the bone. The guide 1 is not shown in these Figures, to clarify the drawing.

The cutter is able to follow the changing shape of the bone as it curves and thickens as the loop is kept tensioned around the bone.

In an automatic process embodying the invention the tool could be mounted on a "robot" arm and suitable control signals, derived in the manner generally described above, applied to move the cutter and applicator.

The technique, described in detail in terms of the specific use in removing rib-bones from bacon backs, is clearly applicable to other deboning operations and appropriate modifications will be apparent to those skilled in the art. The form of driven cutter is much more effective than a sharp knife or plain wire drawn along the bone as these can cut into the bone and snag or break. The technique is readily used for manual and automatic operation. The avoidance of the use of a knife, which can slip and inflict a fatal injury to the user, is a significant improvement in the safety of the operation.

Claims (7)

1. A tool for boning meat including an applicator and cutter, the cutter being an elongate flexible element with repeatedly changing cross-section and the applicator formed to co-operate with a bone end to, in operation, pass a loop of the cutter from around the applicator to around the bone, the tool including means to drive the cutter lengthwise to cut along and round the bone.

2. A tool according to Claim 1 in which the cross-section is changed in at least one of shape and area.

3. A tool according to Claim 1 in which the cutter is a length of nylon monofilament knotted at intervals of about 5 mm to 30 mm and the applicator is a sharp-ended tube or gouge providing a smooth outer surface for the moving driven cutterto slip along and engage around the bone.

4. A tool according to Claim 1 in which the cutter may be driven in one direction continuously or reciprocated.

5. An automatic meat deboning apparatus including a tool of cutter and applicator described above, means to secure a carcase or part thereof, means to examine the carcase to determine the position of a bone end, means to place the cutter around the applicator and to drive the cutter, means to position the applicator over the bone end, means to move the driven cutter off the applicator and around the bone to cut the bone from the meat, means to determine the end of the cutting out of a bone and disengage the cutter.

6. A method of taking meat off a bone including causing a succession of impacts at the junction of the meat and the bone cutting the meat without affecting the bone.

7. A meat deboning tool substantially as herein described with reference to the accompanying drawings.