METHOD AND DEVICE FOR BONING MEAT PORTIONS

Abstract: A method and device for boning meat portions, making use of two opposite pressing elements (2, 3) adapted to be moved to and from eachother, wherein each pressing element comprising a recess provided with inserts (9), along the borderline of the recess each pressing element is provided with means to separate the meat material from the bone or bones, said separating means are following substantially the contour of the bones in the meat portion, for instance the front leg or shoulder portion of a pig, said recess in at least one of the pressing elements is provided with means (75) for locking up or pressing the or each bone piece in length-wise direction thereof and at least one of the pressing elements is provided with gripper members (12, 13) for gripping at least one ridge (17) of a bone; as a result the bone is held firmly in place in a well positioned manner during the meat extracting operation.

Description: The invention relates to a method for boning meat, wherein the bone in a piece of meat is located in between a pair of superposed recesses of two opposite pressing elements, a pressing by means of said pressing elements is applied in transverse direction upon said bone in order to remove the meat from the bone whereupon the meat is separated from said bone while continuing applying said transverse pressure on said bone. Both such a method and such a device are known from EP-A-0 133 332. When the method according to said specification is used, the risk develops, that during the pressing, the bones may damage or break. In practice it appeared that the length of the bones in the meat portion to be pressed is increasing, resulting in bone damage. The aim of the present invention is to avoid said bone damage. This aim is reached in that during the pressure upon said bone, the bone is held under a certain pressure in lengthwise direction to prevent a lengthening of said bone and to prevent the resulting damage to said bone. The apparatus according to the present invention distinguishes itself in that the recess of at least one of the pressing elements bone engaging means are arranged near or at the end portion of each bone for locking up and/or applying a pressure on the or each bone piece in lengthwise direction. Indeed EP-A-0 133 332 discloses an undeformable bridge piece fitting in the cavity which is provided on each of the two yielding supporting members to avoid said problem. It appeared that nevertheless the breaking of bone occurs, so that this specification does not provide a satisfying solution for said problem. According to a further embodiment of the invention at least one of the pressing elements is provided with gripper members for gripping at least one ridge of a bone. As a result the bone is held firmly in place in a well positioned manner during the meat extracting operation. If the meat is removed from at least one cavity of the bone bounding the ridge by inserting one of the set of gripper members into the cavity, this gripper member is used for positioning and holding in place as well as for extracting meat. The meat present in the cavity is thus forced outward by the gripper member. A bone which is well positioned using the gripper members can easily be stripped of meat by being clamped between the gripper members on one side and a pressing element on the other. A simple, extremely well functioning device preferably has clamping jaws, pivoting or sliding relative to each other. The set of gripper members is preferably forced by actuating means outside the pressing surface of a pressing element, whereby at least one stop member cooperating with a gripper member forces the gripper members away from each other. The invention will be further elucidated in the description following hereinafter with reference to a drawing of several embodiments according to the invention, with associated pieces of meat for boning. In the drawing: Figure 1 shows a perspective view of a device for boning meat portions embodying the invention; Figure 2 shows a sectional view like Fig. 8 of the lower and upper pressing elements, the cavity of which is provided with locking up and/or pressing means; Figure 3 is a bottom view of the upper pressing element in Fig. 2; Figure 4 and 5 show a sectional view like Figure 2, detailing the upper pressing element as further embodiment and a bottom view of the upper pressing element in Figure 10 respectively; Figure 6 shows a sectional view of the upper pressing element like Figure 10, provided with a loose insert as further embodiment of the locking up means; Figure 7 shows a sectional view of a detail of the lower pressing element, provided with a further embodiment of the pressing means for pre-loading each bone piece; Figure 8 shows a sectional view along line II-II in Figure 1; Figure 9 shows on a larger scale a perspective view of detail III from Figure 8. Figure 10 and 11 show a cross-sectional view according to line IV-IV in Figure 8, wherein the pressing elements are separated from each other or pressed to each other respectively; Figure 12 shows a cross-sectional view according to line VI-VI in Figure 8; Figure 13 shows on a larger scale a perspective view of a part of the lower pressing element provided with gripper member according to a second embodiment of the invention; Figure 14 shows a sectional view like Figure 8 of the lower and upper pressing element according to the embodiment in Figure 13; Figure 15 is a cross-sectional view of gripping members according to a third embodiment of the invention; Figure 16 shows a top view of a fourth embodiment of the invention; Figure 17 shows on a larger scale a cross-sectional view along line XI-XI from Figure 13. The boning device in Figure 1 comprises a frame 1 of such a rigid structure to withstand high pressing forces between the lower and upper pressing element 2 and 3 respectively. The pressing elements 2 and 3 are arranged opposite to each other and the upper element 3 is rigidly suspended to the top side of the frame 1, and the lower element 2 is supported by a hydraulic cylinder 4 arranged in the lower part of frame 1. Due to the cylinder 4, the piston of which is movable in up and downward direction, the lower pressing element 2 can be moved upwardly starting from the position as shown in Figure 1. Each element 2,3 is provided with a recess 5, which will be elucidated here below. The recess is adapted to receive the bone part in a meat portion M, to be deboned. It is assumed that the operator will put the meat portion M on top of the lower pressing element 2, whereupon after actuation of the hydraulic cylinder 4 the pressing element 2 is urged to pressing element 3, so punching out the bone part from the meat portion M. After having lowered the pressing element 2, the bone parts are left in the recess 5, whereas the meat portion can be removed from between the pressing elements. In order to have the bone part correctly placed near the recess 5, a plurality of members 6 are arranged in straddled relationship to the upper pressing element 3, said members urging the bone parts to the right position in between the lower and upper pressing elements 2 and 3. The working of said elements and the above mentioned device is disclosed in applicants earlier application as mentioned herebefore. It is noticed that in such a device the meat itself is not brought under pressure except for the bone part. Turning now to Figures 2 and 3, the embodiment here is provided with particular inserts in the recess 60 of the lower pressing element 61 and upper element 62 respectively. Lower element 61 is movable in up and downward direction according to arrow P1, what can be embodied by the cylinder 4 in Figure 1. The inserts as shown are partly of solid material, like metal 63, an insert 64 with gripping members 65 corresponding to the embodiment in Figure 14, and yieldable material like rubber 66. The insert 63 in the lower pressing element 61 is supported by the pistons 10. As is clearly depicted in Figure 3, the group of bones B are hingedly connected to each other, whereas the left portion in Figure 3 is the so-called shoulder blade S. According to the invention the recess in both the pressing elements are provided with stop faces 74, which are formed here by the head end of a stub 75, protruding into the recess 60. Said stop face may also be a fixed part of the inner wall of the recess of the pressing element, see for instance at 14'. Hoewever, the stop faces are located such there where the head ends K of a bone B are laying in the recess, whereby the bone is locked up in lengthwise direction. The middle bone in Figure 3 is solely supported at one side by a face 74, since due to its configuration the bone is supported in the hinge of the bone at the right side, so it will be locked up sufficiently. Furthermore it is noticed that in the embodiment as shown in Figure 2 and 3, the upper pressing element is provided with such stop surfaces 74, 74', since the inserts 63 have such dimensions that in the closed position of the upper and lower pressing elements the bone will be received substantially in the upper pressing element. The advantage obtained by the stop faces 74, is that yielding inserts 63 can be avoided easily, whereupon those inserts may be made in harder material, for instance stainless steel. Having an adapted contouring surface of the inserts, the bone will be enveloped rather accurate, and even when using high pressing forces the bone will be a bit deformed, but will not be damaged or fractured. Within the scope of the invention it is possible to provide the stub 75 with an actuating system 76, so being able to bring the stub 75 more or less far protruding in the recess and also the related stop face 74. It is also possible to urge a certain pressure upon the bone in lengthwise direction by means of the system 76, so compensating even in high pressing forces of the pressing element 61, 62 a possible length variation of te bone. The actuating system 76 can be hydraulic, pneumatic or mechanic and it can fully be removed when the stub 75 has the form of a screw bolt. When rotating the bolt in a threaded hole in the wall of the upper element, the face 74 can be brought more or less into the recess thereof. The reciprocating movement of the stub 75 can be effected before the meat portion M with including bone is laid upon the lower pressing element, but it can also be effected when the pressing elements are urged almost to each other, when a certain pressing force upon the bone piece is already available. In that case the hydraulic cylinder 76 can be actuated in order to bring the stub 75 and of course the top face 14 against the head end of a bone in order to obtain the desired compensation force for diminishing the increase of length of the bone piece. In the next embodiment according to Figure 4 and 5 the stub 75 may have another position with respect to the element 62. Figure 4 shows an orifice in the upper pressing element 62 to receiving a stub 75', which is more or less protruding into the recess of the pressing element by means of a corresponding actuating system 76'. The cylindrical surface of the stub 75', here indicated with 74, serves as pressing surface which will contact the head end K of a bone B. The surface is inclined with respect to te direction of movement of the stub 75' in order to preload the bone piece higher, the more when the stub 75' is protruding more into the recess of the pressing element. Figure 6 shows an exchangeable insert 77, the surface 74'' of which facing the recess of the upper element 62 is also inclined, so when moving the pressing element against each other, the bone portion in the recess of the upper element 62 is preloaded in lengthwise direction since the surface 74'' compresses the head end of the bone B. Owing to the inclination of the surface 74'' it will happen that when urging the bone piece more in the upper element 62, the preloading upon the head end of the bone B will raise, which will diminish the increase of the length of the bone, so avoiding damage. The insert 77 is dependent upon the average bone form and is to be exchanged by other inserts, in order to obtain the optimum preloading upon the head end of the bone. This is dependent upon the experience and the skill of the operator. A fourth embodiment of a lock up member for the head end of a bone piece is depicted in Figure 7, wherein a ridge 78 is arranged in the insert 71, its knife-like edge protrudes from said insert. The location of the ridge 78 is near the outer extremity of the insert 71 and so near the head end of a bone B. This knife-like ridge will carve into the bone when closing the pressing elements and in this manner a displacement of the head end is prevented and therefor the increase of the bone length. Turning now to the Figures 8-12, it is noticed that the recess 5 in the lower and upper pressing elements 2, 3 is provided with inserts 7 and 8 respectively, of any suitable material. The pressing surface 9 of the inserts are cooperating such that the remaining space between the inserts when the lower and upper pressing element are pressed to each other will just receive the bone volume, such that all the meat material sticked to the bone parts are urged outwardly. In order to avoid damage to the bone parts, that is to say, splintering or fracture of the bones, the inserts 7 in the lower pressing element 2 may yield downwardly into the lower recess 5 of said element, being possible by the particular support in the form of a piston 10. The lower end of the piston 10 is protruding in a pressing chamber 11, which can be filled with a hydraulic pressure fluid. The fluid pressure is such that a sufficient deboning pressure can be exerted upon the meat but not so high that the bone will damage. It is noticed that the inserts can be made of any suitable material such as flexible material, like rubber, but also metal, like copper etc. The insert 7'''', right in Figure 2, is not supported by a piston 10 as under the other inserts 7, but us supported without any yielding possibility in pressing element 2. Said insert 7'''' is nevertheless provided with a pair of gripping members 12, 13 showing a head portion and a shank portion 14. The shank portion is strip-like and fits into a guiding orifice of a rectangular cross-section formed in the insert 7''''. The head portions of the gripper elements 12, 13 have a particular shape adapted to cooperate with one side of a bone portion, for instance a shoulder blade B. Such a blade B is provided with a ridge 17 and adjacent cavities 15, 16, see also Figures 10 and 11. Furthermore the shank portion 14 of both the gripping elements 12, 13 are oblique to each other, so when lowering te shank portions in the inserts 7'''', the head portions will approach each other; and when moving upwards the head portions will part. In the embodiment shown in Figures 8-11, the gripping elements 12, 13 are supported by a piston 10' corresponding with the pistons 10 underneath the other inserts 7. As is clearly depicted in the Figures 10 and 11 the meat surrounding the shoulder blade B will be urged out of the cavities 15, 16 due to the profiled top surface of the head portions of gripping elements 12, 13, see Figure 11. As soon as the meat is separated from the bone the pressing elements 2, 3 can be separated from each other to the position in Figure 10, whereupon the piston 10' will urge the elements 12, 13 upwardly, so releasing the bone from the lower element. A next meat portion can be entered in between the lower and upper pressing element 2, 3 again, as shown in Figure 10. Turning to the Figures 13-17 several alternatives of the gripping elements 12, 13 are elucidated. In the embodiment according to Figurs 13, 14 the upper pressing element 35 is suspended to hydraulic cylinder 36, whereas a lower pressing element 25 is fixedly secured to a frame. Moreover the inserts are here embodied in rubber material 37. The embodiment of the device 23 as in Figures 13, 14 comprises a pressing frame 24 which has the lower pressing element 25. In pressing element 25 a clamp 26 is forced upward in vertical direction by a compression spring 10'' instead of the hydraulic cylinder. Clamp 26 consists of a non-pivoting gripper member 27 guided only in vertical direction in the pressing element 25 and a gripper member 28 which can pivot relative to gripper member 27 by means of a hinge 61. Gripper member 28 has a projection 29 which cooperates with a stop member 30 of pressing element 25. During upward movement of clamp 26 gripper member 28 pivots in arrow direction 31 as a result of projection 29 striking against stop member 30, this causing the clamp 26 to open. The position in Figures 13, 14 is then reached. A piece of meat M can not be laid on pressing element 25, whereby the piece of meat M, in which a slight incision may or may not have been made beforehand, is placed with its ridge 17 into the opened clamp 26. The rest of the piece of meat M with the bone B shown therein is now placed into the recess 3 of the pressing element 25 adapted for the bone B. An upper pressing element 35 is then driven downward forcefully by means of hydraulic cylinder 36. Through deforming of the rubber 37 the bone B can be enclosed on all side, so that virtually all the meat 39 with the exception of sinew is force out of the press and is there cut off by means of a separating edge 20. It is noted that when the press is closed the clamp 26 is forced downward, as a result of which the gripper members 27 and 28 are forced towards each other, thereby clamping the ridge 17 tightly between them. Both gripper members 27 and 28 thereby penetrate into cavities 15 and 16 on either side of ridge 17, so that the meat being present there is pressed out. There is then created, a continuous upper surface of the pressing element 25 that is well adapted to the underside of bone B. With the device 41 in Figure 15 a lower pressing element is formed by a frame 42 having two gripper members 44 therein which can pivot the shafts 43, which members form, in fited position by means of counterweights 45, an opened clamp in which can be placed a piece of meat M. During downward movement the gripper members 44 pivot downward and then penetrate into the cavities 15 and 16 of bone B. The upper parts and edges of the gripper members 44 are adapted to the underside of bone B. The downward forcing can be carried out by means of an upper pressing element (not drawn). The device 51 from Figures 16 and 17 is adapted for boning a piece of meat M with an end bone 54 that has a ridge 53. With this device 51 the piece of meat M is positioned on a pressing element 55 by means of a clamp 56 with vertically guided, non-pivoting gripper member 57 and gripper member 53 connected thereto for pivoting. In addition, a simpler clamp 59 may be employed for good positioning of the end bone 54 and thereby the entire piece of meat M. A pressing element (not drawn) placed above this and adapted to the upper surface of the bone can be moved downward in order to press out all the meat.

Claims: Method for boning meat, wherein the bone in a piece of meat is located in between a pair of superposed recesses of two opposite pressing elements (2, 3), a pressing by means of said pressing elements is applied in transverse direction upon said bone in order to remove the meat from the bone whereupon the meat is seperated from said bone while continuing applying said transverse pressure on said bone, characterized in that during the pressure upon said bone, the bone is held under a certain pressure in lengthwise direction to prevent a lengthening of said bone and to prevent the resulting damage to said bone. Method according to claim 1, characterized in that at least one ridge of a bone is clamped between a set of gripper members (12, 13). Method according to claim 1 or 2, characterized in that meat is removed from at least one cavity of the bone, bounding the ridge by inserting one of the set of gripper members (12, 13)into said cavity. Method as claimed in any of the claims 1-3, characterized in that a bone is clamped between a set of gripper members (12, 13) clamping a ridge of said bone between them on one side, and at least one pressing element on the other side. A device for boning meat having one or more bone pieces according to the method in any of the claims 1-4, comprising two opposite pressing elements (2, 3)adapted to be moved to and from each other, each element having a recess provided with inserts (7', 7'', 7''', 7'''', 8 and 61, 62) characterized in that the recess of at least one of the pressing elements bone engaging means (75) are arranged near or at the end portion of each bone for locking up and/or applying a pressure on the or each bone piece in lengthwise direction. Device according to claim 5, characterized in that one or more stop faces (74, 74') are arranged in the recess functioning as lock up means. Device as claimed in claims 5 and 6, characterized in that said stop face ( 74) is arranged in a movable manner in said recess. Device as claimed in claims 5-7, characterized in that said stop face (74) is adjustable in continuing manner in the recess of said pressing element. Device as claimed in claim 8, characterized in that the stop face is formed by the head end of a stub actuable by a cylinder (76). Device as to one of the preceding claims 5-9, characterized in that said stop face (74) has an angularity with respect to the pressing direction of the co-operating pressing elements. Device as claimed in claim 5, characterized in that said lock-up means is a ridge (78) protruding into the opposite co-operating pressing element and having a knife-like edge. Device as claimed in claim 5, characterized by at least one set of gripper members (12, 13; 27, 28; 44; 57,58) for clamp gripping on a ridge of a bone. Device as claimed in claim 12, characterized in that at least one gripper member of the set of gripper members (12, 13) is adapted to a cavity bounding the ridge of the bone. Device as claimed in claim 12 or 13, characterized by a relative mobility between on the one hand the set of gripper members gripping the ridge and on the other hand a pressing element gripping on the bone on the same side. Device as claimed in any of the claims 12-14, characterized by a relative mobility of on the one hand a set of gripper members gripping the ridge and on the other hand a pressing element gripping on the opposite side of the bone. Device as claimed in any of the claims 12-15, characterized in that the gripper members (28, 44) can pivot relative to each other. Device as claimed in claim 16, characterized in that the set of gripper members is forced by actuating means (10, 10', 10'') outside the pressing surface of a pressing element, whereby at least one stop member (30) cooperating with a gripper member (28) forces said gripper members away from each other.

Inventors: LANGEN, CHRISTIANUS PETRUS, LANGEN, JOHANNES CHRISTINA
Applicants: LANGEN RESEARCH B.V.
Application year: 1987
Main classification: A22C17
IPC codes: A22C17