IE43302B1 - A method of removing the shoulder blade from a slaughtered animal and an apparatus for carrying out the method - Google Patents

Abstract

1488051 Miscellaneous picking up tools SLAGTERIERNES FORSKNINGSINSTITUT 5 June 1975 [6 June 1974] 24303/75 Heading B4W [Also in Division A2] A gripping member for pulling bones from meat carcases comprises articulated pincers 29 and 30 which are applied by hand and locked in position by sleeve 33.

Description

This invention relates to a method of removing the shoulder blade from a slaughtered animal, particularly a pig carcass, which has previously been divided or bisected. The removal of the shoulder blade from a carcass is required, in particular, when the meat surrounding the shoulder blade is to be used for sliced bacon.

The operation has hitherto been performed with a special instrument, by first loosening the meat from the upper side of the shoulder blade, breaking free the foreleg bone adjoining the shoulder blade head and then breaking the shoulder blade head upwards so as to be able to loosen the meat from the underside thereof and bring the shoulder blade into a position suitable for ultimate withdrawal.

When the loosening of the meat has been completed the shoulder blade can be withdrawn, and this is often done by means of a special apparatus provided with a gripping member that grips the neck of the shoulder blade and is connected to a suitable gear arrangement for manual operation, or to a pneumatic unit for supplying the required force.

The above-mentioned method, however, involves considerable difficulties and it is not possible to strip the meat properly from the underside of the shoulder blade by the procedure employed. In particular, the meat cannot be removed properly from behind the projecting crest Of the shoulder blade.

It is an object of the invention to provide a method of removing a shoulder blade from a slaughtered animal, which will be more effective in practice, than methods in use hitherto. In particular, the invention provides a method which makes it possible to detach the meat effectively from the underside of the shoulder blade, thus obviating the not inconsiderable loss of meat which has occurred with previously used 43303 methods. In the case of pig carcasses, in the past, this loss has usually amounted to 40 to 7° grams per pig.

The method of the invention is applicable to the removal from a slaughtered animal, and in particular from a pig carcass which has previously been divided or bisected, of a shoulder blade bone having a neck portion immediately behind a head portion thereof, the head portion being engaged with the condyle of the foreleg bone of the animal. In the method provided by the invention, a gripping member is engaged around the shoulder blade neck, immediately behind the shoulder blade head which is articulated with the condyle of the foreleg bone, whereupon the gripping member is subjected to a pulling force substantially transversely of the plane of the shoulder blade so that the shoulder blade head is separated from the said condyle and the underside of the shoulder blade is detached from meat adhering thereto, whereafter the shoulder blade is withdrawn in the longitudinal direction thereof.

In this method the meat will be loosened immediately from the shoulder blade, at any rate from the underside thereof where the difficulty in removing the meat from the shoulder blade is greatest because the underside is of a very irregular shape. It has been found that by loosening the meat from the underside of the shoulder blade in this manner, the damage to the shoulder blade pockets will be considerably reduced and the quality of the meat thus improved as compared with meat which has been loosened manually. It may often be expedient, before applying the method of the invention, to loosen the meat from the upper side of the shoulder blade manually, which is a simple and easy operation, but this too may be dispensed with because the loosening of the meat from the upper side can be performed in conjunction with the withdrawal of the shoulder blade, which can be carried out in conventional manner. - 3 4 3 3 0 3 The invention also provides apparatus for carrying out the above-mentioned method, which comprises a pulling member provided with backing means for abutment against the slaughtered animal and connected to or adapted to be connected to a gripping member and adapted to exert a pulling force on the gripping member in a direction approximately transversely of the plane of the shoulder blade. In this apparatus the gripping member can be positioned directly around the shoulder blade neck immediately behind the shoulder blade head and then attached to the said pulling member, or it may be permanently connected thereto in a manner which permits the said manipulation of the gripping member.

When the gripping member has been connected to the pulling member the latter is caused, to raise the shoulder blade neck clear of the foreleg bone so that the meat will be detached at least from the underside of the shoulder blade and the shoulder blade will be placed in the said position for Withdrawal.

In a preferred embodiment of the apparatus according to the invention the gripping member is a drawhook the free hook end of which is provided with a sharp front edge disposed at least approximately in a cylindrical surface about the axis of the bend of the hook while the free hook end extends approximately transversely of the shank of the hook.

This facilitates the introduction of the free hook end along the shoulder, blade neck and the turning of the drawhook so that its shank will face upwards while the hook member slides into position around the shoulder blade neck.

In another embodiment of the apparatus according to the invention the gripping member is formed as a pair of pincers controlled by an articulated scissors type device provided with a locking sleeve slidable along the gripping member so that the gripping member can be permanently secured to the pulling member, and the two jaws of the pincers can be caused to grip the shoulder blade neck in response to an upward pull on the articulated scissors device.

The withdrawal may, as already stated,ba carried out in conventional manner,but a specific embodiment of the apparatus 3 3 0 2 according to the invention comprises a locking guide in which the gripping member can slide under the action of the said pulling member, a withdrawing member connected to the locking guide, for effecting movement of the locking guide in the direction of withdrawal of a shoulder blade, and guide means for guiding the locking guide in such movement, whereby movement of the locking guide under the action of the withdrawing member causes displacement of the gripping member in the direction of withdrawal of a shoulder blade, the locking guide being adapted to cooperate with the gripping member to secure the gripping member in engagement with the neck of a shoulder blade during withdrawal of the shoulder blade.

This particular construction of the apparatus makes it possible to carry out the withdrawal operation in direct continuation of the operation of detaching the meat, so that the entire removal of the shoulder blade can be performed by the same apparatus; the specific form of locking guide employed will retain the gripping member so that it holds the shoulder blade effectively during the pulling action in the longitudinal'direction of the shoulder blade.

Preferably the previously mentioned backing means comprise contact surfaces, one of which extends substantially transversely of the direction of the force exerted by the pulling member on the gripping member and the other of which extends substantially transversely of the direction of the said displacement of the gripping member. This ensures a firm hold on the slaughtered animal both during the loosening of the meat and during the withdrawal of the shoulder blade. To further facilitate the insertion of the drawhook into the locking guide, the locking guide may be a member of U-shaped cross-section which is adapted to engage a shank portion of the drawhook during or after the operation of engaging the drawhook around the neck of the shoulder blade of the animal.

Where the gripping member is constructed as pincers adapted to be opened and closed by an articulated scissors type device, it is preferable that the said locking guide is formed as an internally cylindrical sleeve adapted to engage a cylindrical external surface of the locking sleeve of the scissors device, in order that the gripping member will be able to perform a rotary movement about a vertical axis, so as to be adjusted as closely as possible to the position of the neck of the shoulder blade.

To further facilitate the said adjustment of the position of the gripping member, it is preferable so to dimension the locking guide relative to the articulated scissors device that in the position in which the jaw members of the pincers are closed, the pivotal axes of the jaw members are coaxial so that the jaw members can oscillate jointly about their common pivotal axis.

A preferred method of removing a shoulder blade from a slaughtered animal, together with two preferred embodiments of apparatus for carrying out the method will now be described, by way of example, with reference to the accompanying drawings in which:Figure 1 is a diagrammatic view of a part of the divided carcass of a pig with the position of the shoulder blade marked in dotted lines, Figure 2 shows on a larger scale, the shoulder blade and the adjoining foreleg bone of the pig of Figure 1 during the carrying out of the method according to the invention, Figure 3 is a perspective view of an apparatus according to the invention for carrying out the method, Figure 4 shows a detail of the apparatus of Figure 3 during the withdrawal of a shoulder blade, and Figures 5 and 6 show an alternative construction of the gripping member which forms part of the apparatus of the invention, viewed in two different positions.

Referring to the drawings, Figure 1 shows a pig carcass which has been divided and placed with the cut side facing upwards, which is the position in which a carcass is normally positioned, when the shoulder blade is to be removed. In the drawing the shoulder blade is indicated by dotted lines because it is located below the meat surface. The shoulder blade adheres partially to a piece of cartilage 2 and has a neck portion 3 and a head portion 4 which is dished and forms a socket for the condyle 5 of the foreleg bone 6 which is the upper part of the foreleg of the pig. - 7 43302 Fig. 2 shows the hones more clearly and. with the same designations as in Fig. 1. This drawing illustrates how the method according to the invention Initiates the extraction of the shoulder blade hy cutting it clear of the meat. The shoulder blade and the foreleg hone are shown in a position corresponding to' that of Fig. 1, that is before the procedure is started. The said method foresees the use of a drawhook 7 which is first insertedin the position indicated hy dotted line 8 in which its point 9 can be thrust into and through the relatively thin layer of meat covering the shoulder blade and carried down to one side of the neck of the shoulder blade. By pivoting the hook 7 as indicated by the arrow 10 it is brought into the position shown in Fig. 2 while the hook slides around the shoulder blade neck and catches hold of the neck. The separation of the shoulder blade from the meat is then effected by pulling the drawhook upwards in the direction indicated by the arrow 11, whereby the shoulder blade is raised at the end where it is gripped hy the draw hook and thus pulled away from the foreleg hone 6 simultaneously with the meat being detached from the underside of the shoulder blade where it is most firmly fixed because the underside is of a very irregular shape with a projecting crest. A certain detachment of the meat from the upper side may also he effected hy a slight displacement in the length Wise direction of the shoulder blade during the raising movement.

When the shoulder blade has thus been separated partly from the meat and has also been raised into an inclined position clear of the foreleg hone, it can he extracted from the meat simply by a pull in the longitudinal direction. This can be done in known manner and with known apparatus, hut that requires a separate operation. To obviate this separate operation, which involves removal of either apparatus or pig carcass, the apparatus according to the invention is constructed so that both the separation of the shoulder blade and the extraction can be carried out in the same location and hy means of the same apparatus. This - 8 4 3 3 0 2 apparatus is illustrated in Fig. 3.

Fig. 3 shows the drawhook 7 in the position where its hook member is ready to grip a shoulder blade neck and immediately before an upward pull which will cause the detachment of the shoulder blade from the meat. The drawhook 7 is secured by means of a ring 12 to a hook 13 at the end of a piston rod 14 of a pneumatic cylinder 15 which produces the required upward pull. The cylinder 15 is supported by two columns 16 which are attached to two guide sleeves 17 slidable on guide rails 18 which are braced by means of a transverse bar 19 tovhich is secured a pneumatic cylinder 20. The cylinder has a piston rod 21 disposed parallel to the guide rails 18 and secured to a cross bar 22 connecting the two sleeves 17.

To the cross bar 22 is further secured a U-shaped locking guide 23 for engaging the drawhook 7. Movement of the locking guide 23 and hook 7 can thus be effected by actuation of the cylinder 20 and piston rod 21, the locking guide being guidedin such movement by the guide sleeves 17 and guide rails 18.

Fig. 4 shows the drawhook 7 raised to its uppermost position in which the hook member 24 grips the shoulder blade neck 3, and it will be seen clearly from this figure how the hook end 25 extends substantially transversely with respect to the upwardly directed shank of the hook. It will likewise be seen that the hook end has a sharp front edge 26 which enables it to cut its way into the meat about the shoulder blade neck.

Fig. 4 further shows how the drawhook 7 in the indicated position abuts against the shoulder blade head, which latter also abuts on the locking guide 23 at the back thereof so that the shoulder blade will be held effectively during a pull in its longitudinal direction, the hook being retained by the upward pull and held in position by the locking guide 23 which prevents the hook from turning.

When the shoulder blade has thus been raised by one end, as shown in Fig. 4, it will be possible by actuation of the pneumatic cylinder 20 to cause a displacement of the hook 7 towards the pneumatic cylinder whereby the shoulder blade is subjected to a pull and can be withdrawn from the pig carcass. To retain the carcass during these operations the apparatus, as shown in Fig. 3, is provided with backing means comprising two contact faces 27 and 28 forming together an angle corresponding to the angle between the two directions of pull so that the pig carcass is held firmly both during the separation of the shoulder blade from the meat and from the foreleg, which is effected by the operation of the pneumatic cylinder 15, and during the withdrawal of the shoulder blade, which is effected by the operation of the pneumatic cylinder 20. The backing means comprising the plates 27 and 28 may expediently he constituted by two parts, to make room for the foreleg of the pig carcass.

Figs. 5 and 6 show an alterntive gripping member formed as a pair of pincers with two jaws 29 and 30, which are moved by an articulated scissors type device 31, a so-called Nuremberg gripper, which is articulated to a shaft 32 about which is provided a slidable locking sleeve 33.

In Fig. 5 the locking sleeve is raised so that the gripper is free and the jaws open. In this position the jaws are introduced into the meat and around the neck of the shoulder blade. Fig. 6 shows the position of the jaws enclosing the shoulder blade neck and held in position by the locking sleeve 33. In this position the jaws and the locking sleeve may be moved upwards pneumatically as a unit to separate the shoulder blade head from the foreleg bone and the meat from the underside of the shoulder blade, at which stage the shoulder blade can be withdrawn by the jaws, which are now moved sideways by a locking guide 34. The locking sleeve is mounted slidably in the locking guide 34, both the inner surface of the locking guide and the outer surface of the locking sleeve being cylindrical so that the gripping member can be rotated and displaced within the locking guide.

In the position shown in Fig. 6 the lower articulations of the scissors device are located outside the locking sleeve 33 so that these two articulations can oscillate jointly about their pivots 35 which are coaxial in that position.

Claims (12)

CLAIMS:

1. A method of removing a shoulder blade from a slaughtered animal, in which method a gripping member is engaged around a neck portion of the shoulder blade, immediately behind a head portion of the shoulder blade which is articulated with the condyle of the foreleg bone, whereupon the gripping member is subjected to a pulling force substantially transversely of the plane of the shoulder blade so that the shoulder blade head is separated from the said condyle and the underside of the shoulder blade is detached from meat adhering thereto, whereafter the shoulder blade is withdrawn in the longitudinal direction thereof.

2. A method as claimed in claim 1 in which the meat is first loosened from the upper side of the shoulder blade.

3. An apparatus for carrying out the method as claimed in claim 1, which apparatus comprises a gripping member adapted to be engaged with a shoulder blade of a slaughtered animal, a pulling member connected to or adapted to be connected to the gripping member so as to exert a pulling force thereon, and backing means adapted to abut against a slaughtered animal whose shoulder blade is engaged by the gripping member, whereby the pulling member exerts a pulling force on the gripping member in a direction extending approximately transversely of the plane of the said shoulder blade.

4. An apparatus as claimed in claim 3, in which the gripping member is formed as a drawhook, the free hook end of which is provided with a sharp front edge disposed at least approximately in a cylindrical surface about the axis of bend of the hook, which edge extends approximately transversely of the shank of the hook.

5. An. apparatus as claimed in claim 3, in which the gripping member has the form of pincers adapted to be opened and closed by an articulated scissors type device controlled by a locking sleeve which is slidable along the gripping member.

6. An apparatus as claimed in any of claims 3 to which comprises a locking guide in which the gripping member can slide under the action of the said pulling member, a withdrawing member connected to the locking guide, for effecting movement of the locking guide in the direction of withdrawal of a shoulder blade, and guide means for guiding the locking guide in such movement, whereby movement of the locking guide under the action of the withdrawing member causes displacement of the gripping member in the direction of withdrawal of a shoulder blade, the locking guide being adapted to cooperate with the gripping member to secure the gripping member in engagement with the neck of a shoulder blade during withdrawal of the shoulder blade.

7. An apparatus as claimed in claim 6, in which the said backing means comprise contact surfaces, one of which extends substantially-transversely of the direction of the force exerted by the pulling member on the gripping member and the other of which extends substantially transversely of the direction of the said displacement of the gripping member.

8. An apparatus as claimed in claim 6 or claim 7 as appendant to claim 4, in which the locking guide is a member of U-shaped cross-section adapted to engage a shank portion of the drawhook, such that the locking guide can be engaged with the said shank portion, either during or after the operation of engaging the drawhook around the neck portion of the shoulder blade of an animal - 12 4 3 3 0 2

9. An apparatus as claimed in claim 6 as appendant to claim 5» in which the said locking guide is formed as an internally cylindrical sleeve which is adapted to engage a cylindrical external surface of the said locking sleeve of the scissors device. 5 10. An apparatus as claimed in claim 9, in which the pincers comprises a pair of jaw members connected to two pivots forming part of the scissors device, the pivots being movable into and out of a position in which their pivotal axes are coaxial, during operation of the scissors device, and in which the locking guide is so

10. Dimensioned relative to the scissors device that in the position in which the jaw members of the pincers are closed, the said pivotal axes are coaxial and the jaw members can oscillate jointly about their common pivotal axis.

11. A method of removing a shoulder blade from a slaughtered 15 animal substantially as hereinbefore described with reference to the accompanying drawings.

12. An apparatus for removing a shoulder blade from a slaughtered animal, substantially as hereinbefore described with reference to and as shown in Figures 2 to 4 of the accompanying drawings, or 20 Figures 2 to 4 as modified by Figures 5 to 6 of the accompanying drawings .