Weighing and filling apparatus

Abstract: An apparatus for distributing a combination of portions of a product having a predetermined total weight comprising a plurality of picking units each provided with a gripping means and a weighing means, the gripping means being adapted to grip and remove a portion of the product from a supply of the product and the weighing means being adapted to record the weight of the said portion of the product, a distribution means, and a computer preprogrammed for the predetermined total weight whereby the weighing means is adapted to feed the recorded weight to the computer and the computer is programmed to combine a plurality of recorded weights to give a total weight substantially equal to the preprogrammed weight and to actuate the combination of picking units gripping the combination of portions having a total weight substantially equal to the preprogrammed weight to release and distribute the combination of portions together on the distribution means.

Description: The present invention relates to a weighing and distributing apparatus more particularly to an automatic weighing and distributing apparatus which weighs a number of portions of a product and selects a plurality of portions whose combined weights are substantially equal to a preprogrammed weight. Existing combination weighing machines comprise vibrator chutes to transport the product through the machine and pockets with load cells to weigh the product, see for example EP-A-0 194 815. Such machines are unsuitable for products such as spaghetti and leaf spinach which tend to stick to the vibrator chute surface and interlace around the chute and pocket edges, as well as for diced products with sticky surfaces which cannot be carried through. We have now devised a weighing and filling apparatus which makes use of picking units and conveyor belts instead of chutes and pockets. Accordingly, the present invention provides an apparatus for distributing a combination of portions of a product having a predetermined total weight comprising a plurality of picking units each provided with a gripping means and a weighing means, the gripping means being adapted to grip and remove a portion of the product from a supply of the product and the weighing means being adapted to record the weight of the said portion of the product, a distribution means, and a computer preprogrammed for the predetermined total weight whereby the weighing means is adapted to feed the recorded weight to the computer and the computer is programmed to combine a plurality of recorded weights to give a total weight substantially equal to the preprogrammed weight and to actuate the combination of picking units gripping the combination of portions having a total weight substantially equal to the preprogrammed weight to release and distribute the combination of portions together on the distribution means. A wide variety of products may be weighed and distributed by the apparatus of this invention e.g. a food product such as spaghetti, leaf spinach or peas, or a food product which is in particulate form such as a diced or powdered product. The product is preferably stored in a container which may be constantly fed with product to a level within preset limits. The product level may be controlled by an ultrasonic level sensor or by mechanical levelling means. The gripping means of the picking unit may be a vacuum suction cup or a mechanical grasping hand or claw e.g. with spoon or finger shaped gripping parts. The upper end of the gripping means is attached to a plunger which is capable of opening and closing the gripping means and which is conveniently activated by a pneumatic cylinder. The weighing means of the picking unit is preferably a load cell. Each picking unit preferably comprises means for vertical reciprocating movement so that the gripping means can descend to grip a portion of product and then ascend to remove the portion gripped from the remaining product as well as means for horizontal reciprocating movement so that the gripping means can transport and release the portion gripped onto the distribution means and then return. The means for vertical and horizontal reciprocating movement may be provided by pneumatic cylinders. The distribution means may conveniently be provided by one or more, preferably two, conveyors from which the combination of portions is delivered to an outfeed hopper and then to a packaging machine which may be positioned below the outfeed hopper. The number of picking units used may vary depending on the circumstances. For instance, the minimum number depends on the capacity and accuracy demands while the maximum number may simply be a question of factory space. For example, there may be from 6 to 48 picking units, conveniently from 12 to 36 and preferably from 18 to 30 picking units. The present invention also provides a process for distributing a combination of portions of a product having a predetermined total weight which comprises gripping and removing portions of the product from a supply of the product and recording the weight of each portion by means of a plurality of picking units each provided with a gripping means and a weighing means, feeding the recorded weight of each portion to a computer preprogrammed for the predetermined total weight and programmed to combine a plurality of recorded weights to give a total weight substantially equal to the preprogrammed weight and to actuate the combination of picking units gripping the combination of portions having a total weight substantially equal to the preprogrammed weight to release and distribute the combination of portions together on the distribution means. The present invention will now be further illustrated by way of example only with reference to the accompanying drawings in which Figure 1 is a sectional side view of an apparatus according to the invention, Figure 2 is a section along the line A-A of Figure 1 looking in the direction of the arrows, Figure 3 is a sectional side view of part of the apparatus shown in Figure 1 on a larger scale, Figure 4 is a sectional side view of a picking unit shown in more detail, and Figure 5 is a sectional side view of an alternative construction of a picking unit. Referrring to the drawings, the apparatus comprises a supporting frame 10, an annular revolving trough 11 for holding the product 12 (cooked spaghetti), an ultrasonic lever sensor 13 which controls an elevator (not shown) feeding the trough 11 to maintain the product level within preset limits, and 24 picking units 14 each picking unit comprising a frame 15 supported at one end by a pivot point 16 and at the opposite end by a load cell 17, a horizontal pneumatic cylinder 18, a vertical pneumatic cylinder 19, a mini-pneumatic cylinder 20, a plunger 21 and finger shaped gripping parts or claws 22: the apparatus also comprises two conveyor belts 23 travelling in opposite directions in the direction of the arrows and a central outfeed hopper 24. Beneath the outfeed hopper 24 is a multivac packaging machine 25. In operation, cooked spaghetti 12 is fed onto the trough 11 from an elevator (not shown) at a rate controlled by the ultrasonic level sensor 13 to maintain the product level within preset limits. As the trough revolves the vertical pneumatic cylinders 19 cause the picking units 14 to descend and the mini cylinders 20 cause the plungers 21 to force the gripping parts 22 to descend into the trough 11 and to close and grip the portions 26 of the cooked spaghetti 12 and then to ascend and pick up the portions out of the trough. The portions 26 on each picking unit are weighed by the load cells 17 and the weights are recorded and fed to a computer (not shown). The computer which has been preprogrammed for a predetermined total weight combines the weights of two or more of the portions 26 on the picking units to give a total weight which is equal to or the closest to the predetermined total weight. The computer then activates the horizontal pneumatic cylinders 18 of the appropriate picking units 14 to cause them to move horizontally to a position above the conveyor belts 23 at which position the plungers 21 force the gripping parts 22 open to release the portions 26 of cooked spaghetti from the gripping parts 22 onto the conveyor belts 23 from where they fall off the downstream ends into the outfeed hopper 24 and then into the packing machine 25 where the final packaged product contains a combination of portions of cooked spaghetti having a weight equal to or substantially equal to the predetermined total weight.

Claims: An apparatus for distributing a combination of portions of a product having a predetermined total weight comprising a plurality of picking units each provided with a gripping means and a weighing means, the gripping means being adapted to grip and remove a portion of the product from a supply of the product and the weighing means being adapted to record the weight of the said portion of the product, a distribution means, and a computer preprogrammed for the predetermined total weight whereby the weighing means is adapted to feed the recorded weight to the computer and the computer is programmed to combine a plurality of recorded weights to give a total weight substantially equal to the preprogrammed weight and to actuate the combination of picking units gripping the combination of portions having a total weight substantially equal to the preprogrammed weight to release and distribute the combination of portions together on the distribution means. An apparatus according to claim 1 wherein a container is provided for storing the product, which is constantly fed with product to a level within preset limits. An apparatus according to claim 1 wherein the gripping means of the picking unit is a mechanical grasping hand or claw or a vacuum suction cup. An apparatus according to claim 1 wherein the weighing machine is a load cell. An apparatus according to claim 1 wherein each picking unit comprises means for vertical reciprocating movement enabling the gripping means to descend to grip a portion of product and then ascend to remove the portion gripped from the remaining product. An apparatus according to claim 1 wherein each picking unit comprises means for horizontal reciprocating enabling the gripping means to transport and release the poriton gripped onto the distribution means and then to return. An apparatus according to claim 1 wherein the distribution means is provided by a plurality of conveyors. An apparatus according to claim 1 wherein an outfeed hopper is positioned below the distribution means. An apparatus according to claim 8 wherein a packaging machine is positioned below the outfeed hopper. A process for distributing a combination of portions of a product having a predetermined total weight which comprises gripping and removing portions of the product from a supply of the product and recording the weight of each portion by means of a plurality of picking units each provided with a gripping means and a weighing means, feeding the recorded weight of each portion to a computer preprogrammed for the predetermined total weight and programmed to combine a plurality of recorded weights to give a total weight substantially equal to the preprogrammed weight and to actuate the combination of picking units gripping the combination of portions having a total weight substantially equal to the preprogrammed weight to release and distribute the combination of portions together on the distribution means.

Inventors: WADELL LARS GUSTAF ALBERT, WADELL, LARS GUSTAF ALBERT
Applicants: FRISCO FINDUS AG, FRISCO-FINDUS AG
Application year: 1992
Main classification: G01G19
IPC codes: G01G19