DEVICE FOR SORTING PIECES OF MEAT

Abstract: For sorting pieces of meat, a sorting device contains a fixed con­ veyor belt (1, 2) with weighing means (7) and means (3, 4) for measuring the thickness of the fat layer. In the direction of con­ veyance, a movable conveyor belt (8) is connected to the fixed one, which movable conveyor belt (8) is swung between a number of posi­ tions controlled by a computer to which the measurements are fed. At the respective positions of the free end of the movable conveyor belt (8), additional computer-controlled movable conveyor belts (9, 10) are provided.

Description: The present invention relates to a device for sorting pieces of meat, provided with feeding means for feeding the pieces, weighing means for weighing the individual pieces, sorting means for sorting the pieces of meat on the basis of their weight, comprising at least one endless conveyor belt which connects to the feeding means in their feeding direction and receiving elements for receiving the sorted pieces. Such a device is known from CH-C-487054. Said known device is suitable for sorting sausages on the basis of their weight. It contains an endless conveyor belt the width of which is equal to the accumulated width of the receiving elements. The sausages are displaced in lateral direction over the belt to their corresponding receiving element by means of slanting walls situated above the belt and equipped with switching tongues. This lateral displacement takes places during the feeding movement of the conveyor belt. Therefore, during the sorting operation the sausages are rubbing both over the surface of the endless conveyor belt as well as along the surface of the walls. Such a device is not suitable for sorting pieces of meat like middles. The abrasive action exerted by this device may be acceptable for sausages, but not for pieces of meat. Within short time, the belt, walls and switching tongues would become polluted by the fluid and sticky substituents of the middles. This would give rise to frequent and time consuming cleaning operations. It may even appear to be very difficult to maintain the hygienic standards which are required in the meat industry. A further major drawback of the known device is related to its large lateral dimension. Especially in sorting pieces of meat such as middles, which are larger and therefore wider than sausages, a belt with a considerable width would be required. Such a wide belt is rather cumbersome, and needs correspondingly wide and therefore heavy intermediate supporting means and/or heavy tensioning means. The object of the invention therefore to provide a device which is suitable for sorting pieces of meat such as middles, and which lacks the above disadvantages. This object is achieved according to the invention by the end of the conveyor belt situated nearest to the feeding means being supported by a pivot, the opposite end being supported displaceably by an operating device such that this end is displaceable, in a direction transverse with respect to the longitudinal direction of the conveyor belt, between at least two receiving elements, thickness measuring means, the weighing means and the thickness measuring means being positioned between the feeding means and the conveyor belt, and a computer which receives input signals from the weighing means and from the thickness measuring means, and which on establishing one of at least two quality grades, transmits appropriate output signals to the operating device for the purpose of taking the conveyor belt to the position suitable for the piece of meat to which the input signals relate, in which position it connects to the receiving element corresponding to the established quality grade. With the device according to the invention, a middly lying within certain limits as regards weight and fat layer thickness is now fed to the correct receiving element by the pivotably supported and transversely displaceable conveyor belt. Therefore, the middles are not subjected to any abrasive action. Furthermore, the required width of the conveyor belt is of the same order of the middles being sorted, which allows a simple and little space consuming belt construction. The feeding intervals between the middles are chosen depending on the speed of conveyance and the speed of swinging the conveyor belt. A device for sorting fish on the basis of one criterium, e.g. their length or their transparancy, is known from US-A-4051952. Said device comprises an arcuate trough for slidingly feeding the fishes with regular intervals along detection means towards a transfer trough which is pivotable between two positions. Due to the slippery character of the fish as well as the presence of water, the fish may slide rather easy through said troughs. However, it is not possible to convey a piece of meat by means of such a device. Furthermore, it is not possible to carry out a selection on the basis of two criteria. From FR-A-2576008, a device is known for optically sorting glass particles from a grit mass which contains both the glass particles as well as other particles. The grit mass is shed on an inclined plane, where it is subject to white or infrared light for the purpose of sorting out the glass particles. From the inclined plane, the grit slides towards a set of deflector hammers which are controlled by the light detection means opposite the inclined plane. Depending on their nature, each particle is deflected by a hammer towards one of two collecting planes, over which the sorted particles travel further under the influence of gravity. This known device, though suitable for sorting rather small particles, is not able to handle pieces of meat. Moreover, the inclined sorting surfaces are not suitable for conveying the pieces in a proper way. Finally, the sorting operation is carried out on the basis of only one criterium. A device for sorting fruit on the basis of two characterics, for instance weight and form, is known from FE-A-2530501. It contains a set of tiltable platforms which are conveyed along a track, each platform supporting one piece of fruit. A processor treats the data related to said two characteristics, and controls the tiltable platform for unloading the fruit by rolling at the proper location. The set of tiltable platforms is a very complicated conveyor system, not suitable for conveying pieces of meat. According to the invention, the pivotable conveyor belt can be designed in various ways. For example, it can be such that it swings in the horizontal and vertical plane, in order to convey the pieces of meat, such a middles, to receiving elements which are situated adjacent to and/or above each other. For division into four quality grades, there would then be, for example, two groups of two receiving elements lying above one another. For division into four quality grades, preferably three conveyor belts are provided, the first of which with its opposite end being displaceable between two positions, the end of both other conveyor belts each being supported pivotable adjacent such a respective position and the opposite end of each of them being supported displaceably by a respective operating device such that these ends in a direction transverse with respect to the longitudinal direction of the respective belt are each displaceable between two receiving elements, the computer also transmitting appropriate output signals to the respective operating devices of the second and third endless conveyor belt. The receiving elements are formed, for example, by roller conveyors over which the sorted middles are conveyed further. According to a preferred embodiment, the feeding means comprise a double conveyor belt, each belt part of which in feeding direction being connected to a device for measuring the fat layer of the pieces, a conveyor belt part which connects to the measuring devices in the conveyance direction and having vertical walls sloping towards each other in said direction, which vertical walls are above said conveyor belt part and leave free a passage the width of a piece, and a conveyor belt part with a weighing sensor which connects to the conveyor belt part in the direction of conveyance. Since the middles always have to be held still for the thickness measurement, the working speed of the whole device is determined by the working pace of the thickness measuring device. If the measuring device with conveyor belt is now made double, the working speed of the sorting device can be increased. For the discharge of the middles which meet none of the programmed quality standards, the device is, finally designed in such a way that the second or third conveyor belt has a third position. The invention viii now be explained further below with reference to the drawing. Fig. 1 shows the device according to a preferred embodiment of the invention, in plan view. Fig. 2 shows a sketch with quality grades for the middles from which bacon is made. In Fig. 1 the device is designed with two fixed conveyor belts 1 and 2, each provided with a device for measuring the thickness of the fat layer 3, 4. These measuring devices are of a known type and contain measuring needles which can move from the bottom up through slits in the supporting face, and which have optical detection means which are pushed into the fat layer lying on the supporting face. During the measurement of the thickness the middle is therefore stationary, which is achieved by the supporting face being formed by a conveyor belt working at intervals. Connecting to the measuring devices 3 and 4 is a conveyor belt 5 with guide walls 6 slanting towards each other, through which the streams coming from the measuring device are combined to one. The middles then run over a known weighing conveyor belt 7 with weighing device. Connecting to the weighing conveyor belt 7 in the direction of conveyance is a first swinging conveyor belt 8, which can be swung, e.g. in the horizontal plane between two positions. A second swinging conveyor belt 9 and a third swinging conveyor belt 10 are placed in both positions of the conveyor belt 8, connecting in each case. The conveyor belts 9 and 10 together have four positions, to each of which further conveyor devices 11 or packing or despatch stations connect for discharge of the sorted middles. The swinging conveyor belts 8, 9 and 10 are controlled depending on the data obtained with the measuring devices 3 and 4 and the weighing device 7. This takes place by means of a computer. This computer contains a number of combinations of fat thickness and weight to each of which a quality standard is allocated. An example of a classification into quality grades, depending on the fat thickness and weight, is given in Fig. 2. The four quality grades I, II, III, IV found therein each correspond to one of the four positions of the conveyor belts 8 and 9. Middles falling outside these standards go into area V, corresponding to the third position of conveyor belt 10 for the discharge of rejected middles. A middle with a weight of 12.5 kg, but with too low fat thickness of, say, 8 mm goes into area I and is regarded as unsatisfactory in quality. The computer thus has fed to it the measured value of the thickness of fat layer and the weight, it always compares each combination with the quality standards, and it then controls the conveyor belts.

Claims: Device for sorting pieces of meat, provided with feeding means (1, 2) for feeding the pieces, weighing means (7) for weighing the individual pieces, sorting means (8 - 10) for sorting the pieces of meat on the basis of their weight, comprising at least one endless conveyor belt (8) which connects to the feeding means (1, 2) in their feeding direction and receiving elements (11) for receiving the sorted pieces characterized by the end of the conveyor belt (8) situated nearest to the feeding means (1, 2) being supported by a pivot, the opposite end being supported displaceably by an operating device such that this end is displaceable, in a direction transverse with respect to the longitudinal direction of the conveyor belt (8), between at least two receiving elements (11), thickness measuring means (3, 4), the weighing means (7) and the thickness measuring means (3, 4) being positioned between the feeding means (1, 2) and the conveyor belt (8), and a computer which receives input signals from the weighing means (7) and from the thickness measuring means (3, 4), and which on establishing one of at least two quality grades, transmits appropriate output signals to the operating device for the purpose of taking the conveyor belt (8) to the position suitable for the piece of meat to which the input signals relate, in which position it connects to the receiving element (11) corresponding to the established quality grade. Device according to claim 1, characterized in that three conveyor belts (8, 9, 10) are provided, the first (18) of which with its opposite end being displaceable between two positions, the end of both other conveyor belts (9, 10) each being supported pivotable adjacent such a respective position and the opposite end of each of them (9, 10) being supported displaceably by a respective operating device such that these ends in a direction transverse with respect to the longitudinal direction of the respective belt (9, 10) are each displaceable between two receiving elements (11), the computer also transmitting appropriate output signals to the respective operating devices of the second and third endless conveyor belt (9, 10). Device according to claim 2, characterized in that the feeding means comprise a double conveyor belt (1,2), each belt part of which in feeding direction being connected to a device (3,4) for measuring the fat layer of the pieces, a conveyor belt part (5) which connects to the measuring devices (3,4) in the conveyance direction and having vertical walls (6) sloping towards each other in said direction, which vertical walls (6) are above said conveyor belt part (5) and leave free a passage the width of a piece, and a conveyor belt part (7) with a weighing sensor which connects to the conveyor belt part (5) in the direction of conveyance. Device according to claim 3, characterized in that the second (9) or third (10) conveyor belt has a third position. Device according to any one of the preceding claims characterized in that the pivotably supported end of each conveyor belt (8-10) is rotatable around a vertical axis, such that the opposite end of said conveyor belt (8-10) is dispaceable in a horizontal plane.

Inventors: PERSOON, LEONARDUS JOHANNES HENRICUS
Applicants: PERSOON, LEONARDUS JOHANNES HENRICUS
Application year: 1988
Main classification: B07C5
IPC codes: B07C5