Device for removing the layer of abdominal fat or leaf fat from a slaughtered animal

Abstract: A device for removing a layer on an accessible surface, for instance the abdominal wall, of a slaughtered animal or a part thereof, for instance a pig, of which the abdominal cavity has been opened beforehand, which layer comprises for instance subcutaneous fat, skin, abdominal fat or leaf fat comprises: gripping means for gripping the said layer; and pulling means for pulling this layer loose of the said surface, which pulling means comprise: a rotatably drivable winding mandrel which carries the gripping means and can wind up the said layer during rotary driving.

Description: The present invention is relative to a device for removing a layer of abdominal fat or leaf fat from the abdominal wall of a slaughtered animal or a part thereof, for instance a pig of which the abdominal cavity has been opened beforehand, which device comprises: gripping means for gripping the said layer ; and pulling means for pulling this layer loose of the said surface. Such a device is known from EP-A-0 245 183. According to this prior art the removal of the leaf fat from a slaughtered pig takes place by first gripping the layer at a suitable location by means of mechanical means, particularly clamping means, and subsequently pulling the layer straight up, such that it is teared off. There is hereby a great danger of the leaf fat layer tearing during the stripping operation and a part of the leaf fat remaining behind in the slaughtered animal. The known art further requires a mechanically precise positioning in order to enable a correct gripping of the leaf fat layer. It is an object of the invention to provide a device with which the said layer can be removed from the slaughtered animal very simply and reliably and on industrial scale. To this end the device according to the invention is characterized in that said pulling means comprise: a rotatably drivable winding mandrel which carries the gripping means and can wind up the said layer during rotary driving. The structure according to the invention allows placing the mandrel at very small distance from the layer for winding up and of even holding it in contact therewith. Pressure contact has the advantage that the processed slaughtered animal can be moved in suspended position without the pulling operation resulting in a sideways force being exerted on the animal. The advantage of using a suction aperture according to claim 4 is that the accuracy of positioning does not have to meet high requirements and is even relatively indifferent. In particular an embodiment as specified in claim 8 ensures a sufficiently great force to pull the layer of abdominal fat or leaf fat free of the abdominal wall during rotating drive of the mandrel and to wind it onto the mandrel. It is noted that in principle the suction aperture can take any suitable form. Use can for instance be made of a round opening with a diameter of for example 15 to 20 mm. Use can also be made of a slot aperture extending in lengthwise direction of the mandrel. Use can further be made of more than one opening. Attention is drawn to the fact that a device for removing abdominal fat from slaughtered poultry is known from EP-A-0 486 099. Here the abdominal fat is removed substantially by scraping and suction only. Otherwise than according to the invention this known art makes no use of a winding up of the fat layer and a pulling loose procedure. The known device is thereby unsuitable for removing leaf fat for instance from a slaughtered pig. Furthermore reference is made to EP-A-0 404 235. This prior art specification discloses a device for decropping slaughtered poultry. The specification discloses a rotary driven mandrel comprising a hollow cylinder in the wall of which one or more openings are provided with extensions described as gripping means. It is noted that a decropping operation according to this prior art specification is basically different from an operation according to the invention in which e.g. a leaf fat layer must be removed from the abdominal wall. In decropping the gripping of the inner crop wall takes place over substantially the entire circumference of the rotary mandrel in a way such that the crop is separated from the surrounding tissue in one single action. In the device according to the invention the mandrel performs essentially a winding-up function having the effect of a very well-controlled gentle winding-up of the layer to be removed, such that this layer is teared off the surrounding tissue with great caution and with perfect control during the winding of the separated part of the layer on the winding mandrel. The decropping operation does not require any specific boundary condition for the operation as is the case with the device according to the invention, in which a specific starting position and end position is given, bounding the winding-up operation. It has been found that the measures according to claim 11 enable a comparatively easier removal of the layer of abdominal fat or leaf fat. So that in an embodiment in which the mandrel is in direct pressure contact with the layer for winding via the rolled up leaf fat the mandrel is not impeded during its transverse translation by the protruding spinal column, an embodiment can be useful as specified in claim 12. The measures according to claim 13 enable an easy release of the rolled up layer, that is, by sliding it off axially. Unintended sliding off is prevented by a device as according to claim 14. The winding operation performed by the mandrel has great technical advantages. Winding up can take place while taking up relatively little space. This in contrast to the gripping of the relevant layer and the pulling loose thereof by translation. It will be apparent that a relatively large free space must be available for this purpose. Winding up has the further advantage that the distribution of force can be very uniform. A further advantage of winding up is that the mandrel can be adapted and placed such that the distance between the tear zone and the winding zone can be relatively small. This distance can even be minimal. In this latter case there is pressure contact between the mandrel and the surface to which the layer for removal is adhered, optionally via one or more already rolled up layers. This embodiment provides the option of processing the animal or a part thereof in the hanging position. Due to the described pressure contact no net sideways directed force is in any case exerted, whereby the animal for processing remains in position. The measures according to claims 4, 5, 6 and 7 can be applied for effective gripping of the relevant layer. The measures according to claim 9 in particular ensure a non-slip winding up after a first contact. The measures according to claim 10 are intended to make the process as controllable as possible. Claims 2 and 3 give measures enabling a smooth and reliable winding onto the winding mandrel without the danger of unintended tearing into the layer. The measures as specified in claim 12 are intended to ensure that the winding mandrel does not meet any obstruction from the spinal column during the winding and the translation movement. The abdominal fat or leaf fat layer for removal adjoins the midriff with an edge and has a first end zone tapering more or less to a point on the abdominal side and a second end zone tapering more or less to a point on the posterior side. These two zones are the most critical in the removal of the layer because of their tapering form. In this regard the invention further relates to a device according to claim 15. A reliable pulling loose is hereby ensured without there being a danger of unintended tearing into the layer. Practical implementations hereof are given in claims 16 and 17. Claim 17 gives a preferred embodiment. Claims 2 and 15 in combination provide the possibility of roughly following the form of the edge. In combination herewith the variant of claim 18 is preferably applied. The invention will now be elucidated with reference to the annexed drawings, wherein: figure 1 shows a partly broken away perspective view of a device according to the invention at the start of a procedure; figure 2 shows on enlarged scale the detail II of figure 1 ; figure 3 shows the cross section III-III of figure 2; figure 4 shows a perspective view corresponding with figure 2 during a subsequent phase; figure 5 is a perspective view of the winding mandrel according to the foregoing figures prior to the gripping; figure 6 shows a second embodiment of a winding mandrel in perspective view; figure 7 shows a third embodiment of a winding mandrel in perspective view; figure 8 shows a fourth embodiment of a winding mandrel in perspective view; and figure 9 shows a fifth embodiment of a winding mandrel in perspective view. Figure 1 shows a device 1 for removing the leaf fat layer 2 from a pig of which in this case the chest cavity and abdominal cavity have been opened and the intestines removed. The device comprises a winding mandrel 4 rotatably drivable by means of a motor 3 and supported by an adjustable frame 5 which is guided for up and downward movement by a vertically extending rail 6. As shown in figure 1, the leaf fat layer is adhered with a curving edge 7 with increased adhesive force to the midriff 8 and has a first end zone 9 tapering more or less to a point on the abdominal side of the pig 10 and a second end zone 11 tapering more or less to a point on the back side of the pig 10. The winding mandrel 4 is adapted and placed in the drawn embodiment for gripping the first end zone 9. Figure 2 shows the winding mandrel 4 on enlarged scale. This is supported by a hollow shaft 12 which is connected to a suction pump (not shown). The mandrel 4 itself also takes a hollow form and has two suction apertures embodied as slotted holes 13 and 14. See also figure 3 in this respect. As figure 3 shows, the winding mandrel 4 has a roughly semi-cylindrical form with a flat longitudinal wall 15 which carries a bent plate 16. The combination of the slotted hole 14 and the bent portion 17 of plate 16 ensures that end zone 9 is effectively sucked in. It is noted that the bent plate can also have an opposing orientation. It is possible to achieve hereby that the force exerted by the mandrel on the leaf fat layer can rapidly become greater after gripping thereof because the bent plate applies a relatively great local pressure on the gripping zone, which improves the reliability of the connection. Figure 4 shows the manner in which by rotary driving as according to arrow 18 the layer 2 is wound onto the winding mandrel 4 while simultaneously being pulled free from the abdominal wall 19. Figure 1 shows that the translation direction 20 of winding mandrel 4 corresponds, with relatively small variation, with the direction of the chord 21 between end zones 9 and 11. The leaf fat layer 2 is hereby pulled loose such that the tear zone resulting during tearing displaces continuously along the edge 7. Figure 5 shows the situation in which the winding mandrel 4 approaches the first end zone 9. Figure 6 shows a winding mandrel 28 which differs from winding mandrel 4 insofar that it is has an outer surface provided with ribs 22. The suction force applied to the first end zone 9 can herewith be effectively increased, as it were, by a locally increased pressure on the layer 2. Figure 7 shows a winding mandrel 29 with a slightly tapering end zone 24. Due to this shape the rolled up leaf fat layer 2 can easily be released by axial sliding. This embodiment also comprises suction apertures 25. A bent plate 26 is also used. Figure 8 shows a winding mandrel 27 with a rounded end 28. This mandrel has a more or less smooth outer surface and is provided with one suction aperture 30 in the form of a slotted hole with a length of about 50 mm and a width of about 3 mm. Figure 9 shows a winding mandrel 31 with a widened end 32. Otherwise than in the case of the winding mandrels described in the foregoing, as will be apparent, the rolled up leaf fat cannot be pushed off by axial displacement of the mandrel. The advantage of this mandrel is that an unintended and undesired sliding off is therefore blocked. The drawback is that the rolled up leaf fat layer 2 can only be removed by being unwound.

Claims: Device (1) for removing a layer (2) of abdominal fat or leaf fat from the abdominal wall of a slaughtered animal or a part thereof, for instance a pig (10) of which the abdominal cavity has been opened beforehand, which device (1) comprises: gripping means (13, 14, 16) for gripping the said layer (2); and pulling means (3, 4) for pulling this layer (2) loose of the said surface; characterized in that said pulling means (3, 4) comprise: a rotatably drivable winding mandrel (4) which carries the gripping means (13, 14, 16) and can wind up the said layer (2) during rotary driving. Device (1) as claimed in claim 1, wherein the mandrel (4) is adapted to perform a transverse translation. Device (1) as claimed in claim 2, in which the translation corresponds within about 30° to the direction of a chord (21) between tapering end zones (9, 11) of an edge (7) of the said layer (2) adjoining the midriff (8) . Device (1) as claimed in claim 1, wherein the gripping means comprises at least one suction aperture (13, 14) for placing against the said layer (2). Device (1) as claimed in claim 4, wherein the suction aperture has an elevated peripheral edge. Device (1) as claimed in claim 4, wherein the suction aperture has a surface of at least 1.5 cm 2 . Device (1) as claimed in claim 1, wherein the gripping means comprise mechanical means, for instance clamping means. Device (1) as claimed in claim 7, wherein the pulling means also comprise clamping means which can co-act for instance with the suction aperture. Device (1) as claimed in claim 1, wherein the mandrel (28) has a peripheral surface with a profiled form (22) such that locally the grip on the layer (2) of abdominal fat or leaf fat is strengthened. Device (1) as claimed in claim 1, wherein the gripping means can be controlled so as to grip a tapering end zone of the said layer. Device (1) as claimed in claim 1, comprising cooling means for cooling at least the said layer (2) prior to removal of the leaf fat. Device (1) as claimed in claim 1, wherein a free end zone of the mandrel is movable in lengthwise direction. Device (1) as claimed in claim 1, wherein the mandrel has a slightly tapering shape toward a free end. Device (1) as claimed in claim 1, wherein the mandrel (31) has a widened end (32). Device (1) as claimed in claim 1 for removing the layer (2) of abdominal fat or leaf fat from a slaughtered animal or a part thereof, for instance a pig (10), of which the abdominal cavity has been opened beforehand, which layer (2) adjoins the midriff (8) with an edge (7) and has a first end zone (9) tapering more or less to a point on the abdominal side and a second end zone (11) tapering more or less to a point on the back side, which device (1) comprises: gripping means (3, 4) for gripping at least one of the said end zones (9, 11); and pulling means (3, 4) for pulling loose the layer (2) of abdominal fat or leaf fat in a direction (20) such that the tear zone(s) occurring during stripping move(s) continuously along said edge (7). Device (1) as claimed in claim 15, wherein the pulling means (3, 4) are adapted to pull loose the said layer from one of the said end zones in a direction which differs by at least 10° from the principal direction of the spinal column. Device (1) as claimed in claim 15, wherein the pulling means (3, 4) are adapted to displace both said end zones (9, 11) such that the tear zone(s) extend(s) at least more or less parallel to the chord (21) between both end zones (9, 11). Device (1) as claimed in claim 15, wherein the mandrel (4) is pivotable such that the tear zone always extends at least more or less transversely of the edge (7). Device (1) as claimed in claim 18, wherein the mandrel has a form adapted to the pivotability and widening toward its free end. Device (1) as claimed in claim 17, wherein the mandrel is guided to perform the winding operation under pressure contact between the chest wall and the mandrel largely via the layer (2) of abdominal fat or leaf fat already wound thereon.

Inventors: JACOBS THOMAS GERARDUS MARIA, KIPPERSLUIS BERNHARD ANTON VAN, OCHTEN SANDER ANTONIE VAN, TIGGELOVEN LEONARDUS JOZEPHUS, JACOBS, THOMAS GERARDUS MARIA, TIGGELOVEN, LEONARDUS JOZEPHUS ANTONIUS, VAN KIPPERSLUIS, BERNHARD ANTONIUS MARIA, VAN OCHTEN, SANDER ANTONIE
Applicants: STORK MPS BV, STORK MPS B.V.
Application year: 1995
Main classification: A22B5
IPC codes: A22B5