METHOD AND APPARATUS FOR REMOVING MEAT
This invention relates to a method and apparatus for the removal of meat in a substantially intact form (ie. whole- tissue meat) from a part of the carcass of a slaughtered animal.
The manual boning of meat from carcasses of slaughtered animals is a labour-intensive operation and as such the processing costs involved in producing boneless whole-tissue meat are high.
In our New Zealand patent specification 228761/229449 we have disclosed a method and apparatus for whole-tissue meat removal from a part of a carcass. The apparatus disclosed in our aforementioned patent specification has provided a mechanical means of achieving clean and high meat yield removal in the area of the vertical and lateral protrusions of the vertebrae. The method performed by the apparatus of patent specification 228761/229449 includes the forming of a cut along the side of the vertical protrusions of the vertebrae followed by forcing the whole-tissue meat from the bone by relative movement between the carcass part and a plough or clearing means.
This apparatus and the method of meat removal performed thereby has been particularly successful when processing a carcass part from a small animal such as a sheep or pig. However, while the method is able to be successfully performed on larger carcass parts such as from a beef animal the apparatus disclosed in our aforementioned patent specification is not suited for removal of whole-tissue beef meat from a carcass part. This is in part due to the wide variations in shape and dimensions of beef carcasses. These variations present considerable difficulties in being able to provide a mechanical means of consistently and cleanly achieving a high yield of meat removal.
The object of the present invention is thus to provide mechanical apparatus suitable for removal of whole-tissue meat from an animal carcass part from a large animal such as a beef animal.
Broadly in one aspect the present invention consists of apparatus for the removal of whole-tissue meat from a part of a carcass of a slaughtered animal the apparatus comprising support means for supporting a part of the carcass, cutting means, clearing means and moving means for causing relative movement between said support means and said cutting means and clearing means, said cutting means including first and second cutting elements which upon such relative movement occurring form cuts in the meat along the line of the spinal process of the carcass part and at least over the transverse process, said cuts being at least partially formed in advance of a clearing action by the clearing means during said relative movement.
Preferably the apparatus also includes pressure applying means for causing a pressure directed toward said support means to be applied to said clearing means such that contact occurs between the bones supported by the support means and said clearing means. Preferably the clearing means comprises a plough element being of rigid and fixed shape.
Preferably the pressure applying means causes pressure to be applied in two different directions.
Also according to a preferred form of the invention pressure applying means cause pressure to be applied to the cutting means in at least one direction relative to the support means, but preferably two different directions.
According to a further broad aspect of the invention there is provided a method of removing whole-tissue meat from a part
of a carcass of a slaughtered animal the method comprising the steps of fixedly locating said carcass part thereof on a support, making longitudinal cuts in the meat along the line of the spinal process of the carcass and at least the transverse process of the carcass and causing clearing means to move longitudinally along said carcass part to force tissue therefrom.
In the following more detailed description of the invention according to its preferred from reference will be made to the accompanying drawings in whic :-
Figure 1 is a side elevation view of the apparatus, Figure 2 is an end view of the apparatus shown in Figure
1, Figure 3 is a partial plan view showing the inter¬ relation of the support carriage, cutting knives and ploughs,
Figure 4 is an end elevation of the support carriage showing support tables engaged and disengaged with the carcass parts carried by the carriage,
Figure 5 is a similar view but showing rib supports engaged and disengaged with the carcass parts carried by the carriage, Figure 6 is an enlarged elevation view of the knives and plough,
Figure 7 is a partial end elevation illustrating the knives in conjunction with a carcass part held on the carriage and showing the operating mechanism for the knives, Figure 8 is a similar view to Figure 7 but showing the inter-relationship of the plough, carcass part and the operating mechanism of the plough,
Figure 9 is a perspective face view of a plough, and Figure 10 is a underside view of a plough.
Referring firstly to Figure 1 of the drawings the apparatus comprises a chassis or body 10 having feet 11 and a vertically orientated column 12 at one end thereof. The
upper end of column 12 carries a support arrangement generally shown at 13.
Located either side of column 12 are a pair of arms 14 and 15. These arms are independently pivotable about (a) a substantially horizontal pivot axis of a shaft 16 projecting laterally from column 12 and (b) the axis of stub shafts 16a this axis being normal to the pivot axis of shaft 16. At the outer or free end of arm 14 a cutting arrangement 17 is carried while at the free or outer end of arm 15 a plough 18 is mounted.
Located on chassis 10 for sliding movement toward and away from column 12 is a carriage 19. An operating mechanism (not shown) is located within chassis 10 so as to effect movement of the carriage 19 toward and away from column 12. This operating mechanism and the guide means for effecting such movement of carriage 19 can take various forms which are well within the scope of the skilled person and therefore will not be described in any detail in the specification.
In the illustrated form of the invention the apparatus is configured to remove meat from a loin or loin/rack taken from a beef carcass. The loin is a section of the spine which includes all the lumber vertebrae. This includes the chine, the spinal process (the vertical dorsal projections or commonly featherbone) , the mannillary process (knuckle), the transverse process (the lateral protrusions) and the meat thereon. However, the loin can include part of the rack (being part of the thoracic vertebrae) and therefore include ribs, more generally 1 or 3 ribs. Thus in the following the term loin will indicate that part of the carcass which includes some but more particularly all the lumber vertebrae and one or more thoracic vertebrae.
Carriage 19 incorporates clamping means whereby the loin L can be clamped in position. In the illustrated form of the
invention and during one operating cycle thereof loin L will be clamped either side of the carriage. In the following description, however, reference will generally be made to a single loin L clamped to one side or clamping surface 25 of the carriage and operated on by the knife arrangement 17 and plough 18 associated with that side of the carriage.'
Extending longitudinally along the side of the carriage is a ridge 20 which engages within the generally semi circular groove of the loin L which results from the carcass, from which the loin has been taken, having been split substantially diametrically through the passage for the spinal column. This inter-engagement of ridge 20 in the recess of the loin L forms an initial location of the loin on the carriage.
The carriage also incorporates a table 21 which has a small lateral ridge 22 at its forward end. To further position the loin in place this ridge 22 is positioned by the person loading the loin so that it is between the first transverse process and the adjacent rib if such is present.
With the loin so positioned (see right hand side of Figures 2 and 4) operation of the machine commences whereupon the clamp mechanism operates to clamp the loin in place and the table
21 becomes elevated as shown at the left hand side of Figure
4.
The clamp mechanism includes a plurality of clamp plates 23 having saw teeth 24 projecting therefrom and located opposite the clamping surface 25 of the carriage 19 which incorporates ridge 20. These clamp plates 23 are controlled in movement by pneumatic rams located within carriage 19 with the piston rods 25 or connections coupled with the piston rods thereof being bolted to plate 23 (see more particularly Figures 7 and 8). Thus when the clamp plates are drawn toward the clamping surface 25 the saw teeth 24 bite into the chine bone.
Table 21 is mounted by flanges 26 to a pivot axle 27 pivotally carried by connecting elements 28 mounted with the piston rods 29 of pneumatic rams. Accordingly the table 21 can be elevated to engage with the underside of the transverse process and in doing so the table 21 pivots about the axis of pivot shaft 27. In addition table 21 is preferably formed of a resilient material so that it can flex and at least in part conform with the contour of the underside of the transverse process due to the interaction of the table and the transverse process under the influence of the pneumatic ram. As illustrated in Figure 2 this upward force applied to the transverse process also causes the transverse process to tend to straighten.
When the table 21 is lowered it assumes a more or less horizontal rest position due to a finger 30 carried by a collar 31 connected to table 21 engaging with a stop 32.
In the preferred form of table 21 a longitudinal strengthening flange or ridge 33 extends along the edge of the table but terminates short of the ridge 22.
Located adjacent the forward end of table 21 are a pair of rib supports 34 which are of general elongate form and are located once again on the end of a piston rod 35 of a pneumatic ram. As shown in Figure 5 the rib supports 34 can elevate from a rest position (right hand side of Figure 5) to a raised position (left hand side of Figure 5) where they engage with the tissue between the ribs located forward of ridge 22. This action ensures correct presentation of not only the ribs but also the tissue therebetween so as to achieve cleaner and higher yield removal of meat in this somewhat flexible region of the loin.
Therefore initial operation of the machine involves the operator placing the loin in position relative to ridge 20 and 22 whereupon the clamp plates 23 clamp the chine bone to
the clamping surface 25 and the table 21 and rib supports 34 elevate so as to present the rib portions of the loin in the optimum position for high yield and clean whole-tissue meat removal.
The carriage 19 then commences its travel toward column 12.
As a consequence of this the loin comes into engagement with knife arrangement 17. After the leading knife 35 has cut part way into the tissue arm 14 is moved laterally about pivot axis 16a (as will hereinafter be described) such as to draw the leading knife 35 into close engagement with the featherbone. This ensures that the initial cut of the leading knife 35 is into the meat and not with the bone. This is the preferred form of operation as it allows for variations in the thickness of the leading end of the featherbone from one loin to the next.
Referring to Figures 6 and 7 the lead knife 35 is mounted on a collar 36 carried by arm 14. Knife 35 angles rearwardly toward column 12 and includes a lateral foot 37 formed with a cutting edge 38. The trailing edge of knife 35 includes a lug or flange 39 which engages with the inboard surface of second or trailing knife 40. The swept back leading edge of knife 40 is formed as a cutting edge 41 while the lower end of the knife 40 also includes a foot 42 with a rearwardly disposed and downwardly projecting wing 43. The leading edges of foot 42 and wing 43 are formed as cutting edges 44 and 45 respectively.
In Figure 2 the right hand side shows the knife arrangement 17 (and plough 18) in the waiting position which is lower than the level of the leading rib or transverse process. As can be seen in Figure 6 the cutting edge 38 of knife 35 is rounded so that the edge can come into contact with the leading rib or transverse process and ride up in the required cutting position which is as close as possible to the transverse process.
Trailing knife 40 is also mounted to arm 14 by a collar 46. Unlike collar 36 the collar 46 is able to rotate on arm 44 but it is influenced by biasing means such as a spring bias. Thus knife 40 can move away from stop 39 against the biasing effect. There is an overlap between cutting edges 38 and 44 of feet 37 and 42 so that a continuous cutting edge (see Figure 7) is provided. The amount of overlap is such that in the event that knife 40 moves relative to knife 35 the continuous cutting edge is maintained. The trailing edge of knife 35 includes a deflector 47 which deflects meat away from the following or second knife 40.
As shown in Figure 7 knife 35 forms a vertical cut in the meat adjacent the featherbone. Cutting edges 38 and 44 form a cut adjacent the transverse process. Wing 43 with its cutting edge 45 engages over and cuts along the line of the knuckle.
As shown in Figure 7 arm 14 includes in its length a projection 48 which is connected at 49 to ram 50. This ram 50 controls the raising and lowering of arm 14 so that if a sensor associated with carriage 19 detects that no loin has been clamped on the particular side of the carriage 19 on which arm 14 is located the ram 50 does not actuate. As a result arm 14 is not lowered and the knives 35 and 40 do not assume their cutting position if no loin is clamped to the carriage on the side where the knives are located.
Also coupled with projection 48 is a pneumatic ram 51 which applies a lateral force to arm 14 so as to move the arm laterally about pivot axis 16a after a proximity sensor has determined that leading knife 35 has engaged with the tissue as previously described. Ram 51 then continues to apply a lateral inward force so that the cutting blade 17 follows as closely as possible the featherbone. As a consequence variations in the thickness (usually gradually increasing) of the vertical protrusions is automatically compensated for.
Plough 18 is of fixed shape and in the preferred form of the invention is of steel construction. As with arm 14 the plough arm 15 has a projection 52 which is coupled with a pneumatic ram 54 which raises and lowers arm 15 in a manner corresponding to the raising and lowering of arm 14. Also connected to projection 53 is a ram 55 which applies lateral movement to arm 15 about pivot axis 16a and a continual lateral biasing force in the same manner as ram 51 coupled with arm 14.
Plough 18 has a profiled leading edge 56 which engages with the rib(s) and transverse process in such a manner that the tissue is forced therefrom but no damage thereto is caused. To this end ram 54 is a double section ram having a first section which moves arm 15 downwardly until a leading projecting knife 57 engages on the knuckle. (This knife forms a further cut along the knuckle but deeper than the wing 43 of trailing knife 40 so that the tissue is cut down to the junction of the knuckle with the transverse process.) The second section of ram 54 then applies a continual downward force so that there is an interaction between the profiled edge 56 and the transverse process. This downward pressure is such that the contact between the plough 18 and the transverse process is sufficient that contact is made with the transverse process so that meat is forced away from the transverse process. The pressure is, however, not such that the plough digs into the transverse process or causes damage thereto which may lead to bone splinters etc.
Accordingly in operation of the machine a loin L is clamped either side of the carriage whereupon the carriage moves toward column 12 and knives 35 and 40 form cuts along the featherbone, the transverse process and over the knuckle. The following plough completes a cut around the knuckle (via knife 57) down to the transition with the transverse process while the profiled leading edge 56 of the plough 18 forces the meat from the transverse process. Once the knife
arrangement 17 and plough 18 have cleared the loin and carriage 19 is at the end of its travel the clamp plates 23 are actuated to release the bone from which the meat has been removed whereupon the bone can be removed manually or preferably by suitable mechanical means such as a robotic arm, pick and place clamp etc. Adjacent the end of the travel of the carriage 19 conveyors, trays or other means can be provided to catch and convey away the meat removed from the bones.
As a consequence the present invention provides an apparatus for removal of whole-tissue meat from a carcass part of a beef animal. The variations in size of one carcass part to the next are compensated for by the continually adjustable nature of the knives and plough as the carcass part moves relative thereto. Further compensation for the differing sizes and configuration of carcass parts are achieved by the ability of the table and rib supports to conform with the shape and configuration of the carcass part.