DEVICE FOR THE SELECTIVE TRANSFER OF SLAUGHTERED POULTRY, SUPPLIED ON A CONVEYOR TRACK, TO ONE OR MORE DISCHARGE STATIONS, UNDER CONTROL OF AT LEAST ONE GRADING STATION DISPOSED ALONG THE DISCHARGE CONVEYOR TRACK

Abstract: Device for the selective transfer of slaughtered poultry, supplied on a conveyor track (5), to one or more discharge stations (15, 17, 19), under control of at least one grading station (7, 9) disposed along the conveyor track, with a control device in each discharge station (15, 17, 19) for removing from the conveyor track (5) poultry selected by the grading station (7, 9), a buffer device in which the birds to be discharged can be temporarily stored, and a device for taking the birds to be discharged into the desired discharge position.

Description: As part of the evolution which the processing of slaughtered poultry is going through, there is an increasing need for selection of the said slaughtered poultry - which is supplied on a conveyor track and has undergone all operations as regards removal of the intestines, etc. - according to quality, weight and possibly further processing, for example jointing operations. Set up along the conveyor line for this purpose are grading stations which grade the poultry according to different quality aspects such as type, good condition, size, colour, weight, etc., and each of which transmits signals which are processed in a computer system which controls an ejection station the moment the particular graded poultry reaches this station; the poultry is then removed from the conveyor track. Such an installation is described, for example, in the brochure published by the applicants: "Chickway 2/2 - electronic on-line grading system". The poultry then has to be conveyed in a particular position to the packing plant, in which packing equipment places the poultry individually, or in a particular number, in suitable packs. Further processing of the poultry in a number of so-called jointing stations, along which the poultry are conveyed, hanging by the legs, and in which they are jointed into portions to be packed separately, is increasingly common: here the particular requirement set is that the poultry selected from the conveyor track is taken to a particular position on the jointer track without human intervention. Account must be taken here of the fact that in general the conveyor line will have a greater supply capacity than the discharge capacity of the individual discharge stations, while in practice there is a possibility that the discharge capacity of a particular discharge station will be inadequate to take the supply from the conveyor line, namely when a particular grading station successively designates a particular number of poultry for a particular discharge station. The device according to the invention must be designed in such a way that account is taken of this possibility. US-A-3 944 078, which discloses the features of the preamble of claim 1, 7 discloses a device for the selective transfer of slaughtered poultry, supplied on a conveyor track, to one or more discharge stations, under control of at least one grading station disposed along the conveyor track. Each discharge station comprises a control device for removing from the conveyor track poultry selected by the grading station for that particular discharge station, and a buffer device in which the birds to be transferred can be temporarily stored. The object of the invention is to produce a device by means of which the above-mentioned tasks can be fulfilled. This is achieved according to the invention in that the device comprises a second conveyor track, and in that the buffer device comprises an infeed station cooperating with the first conveyor track, a discharge station cooperating with the second conveyor track and an endless transfer track accommodated between the infeed station and the discharge station, the endless transfer track having guided along it transfer hooks which can either stop or be driven along the transfer track, while in the direction of movement along the transfer track in front of both the infeed station and the discharge station there is sufficient space for the accumulation there of a number of empty and poultry-carrying transferhooks respectively, and a first stop is arranged for the release one by one of empty transfer hooks to a position for cooperation with the first conveyor track for removal of poultry from the first conveyor track, and a second stop is arranged for the release of the poultry-carrying transfer hooks to a position for cooperation with the second conveyor track for removal of poultry from the transfer hooks. Since the distance between the grading station and the infeed station is fixed and known, while the speed at which the poultry moves along the first conveyor track is also fixed and known, it is no problem, when the grading station indicates poultry which has to be discharged to the second conveyor tack in question, for a signal to be transmitted so that just at the moment at which the poultry is approaching the infeed station, the first stop releases the transfer hook which is there in front of it and is still being retained by the stop, and this hook then takes over at the correct moment the poultry from the first conveyor track and transfers it to the discharge station. If more poultry has already accumulated in front of this discharge station, the transfer hooks in question stop and are released one by one by the second stop at a speed adapted to the speed of movement of the second conveyor track, and taken in such a way in front of the second conveyor track that they can be accommodated there. The transfer track is preferably designed as a fixed circular first ring, coaxial with a rotary driven second ring, and the transfer hooks are guided on the first ring and are provided with friction blocks for cooperation with the second ring. In particular, if the poultry selected has to be conveyed to an installation of the type in which the poultry undergoes a number of successive jointing operations, and in which the poultry is moved forwards with the legs clamped against fixed guides, the device according to the invention is characterized in that in the first conveyor track the poultry is moved along hanging by the legs from suspension hooks, and in the second conveyor track is moved along with the legs clamped against fixed guides, the plate-shaped transfer hooks are designed with take-up slots, the first conveyor track at the infeed station, where the poultry is pressed by a guide disposed along the first conveyor track out of the suspension hooks into the transfer hooks, is tangent to the transfer track, and the second conveyor track at the discharge station, where the poultry is pressed by an ejector from the overhang hooks between the second conveyor track guides, is at right angles to the transfer track. A further advantageous embodiment comprises detectors disposed along the transfer track, for determining the number of transfer hooks accumulated in front of the infeed station or discharge station, while a control device for the first and second stop is designed in such a way that the first stop cannot be released when the number of hooks accumulated before the second stop exceeds a particular value, and the second stop cannot be released when the number of hooks accumulated in front of the first stop exceeds a predetermined value. Preferably, each stop has a tilting arm which hinges about a shaft which is parallel to the rotary shaft of the second ring, said arm being designed with two spaced stops, each cooperating with a boss on each of the transfer hooks. It is pointed out that the grading station can be a weighing device. The invention will be explained with reference to the drawing, in which: Figure 1 is a general drawing of a complete plant for the grading and transfer of poultry to different jointing and processing stations. Figure 2 is a schematic top view of a preferred embodiment of the device according to the invention, intended in particular for the transfer of selected poultry to a so-called jointing line. Figure 3 is a bottom view of this embodiment. Figure 4 is a schematic side view of the transfer track. Figure 5a is a top view of a transfer hook, also called an overhang hook used in this device. Figure 5b is a partial side view, partial cross-section of this overhang hook. Figure 6a is a bottom view of a controlled stop with drive therefore. Figure 6b is a side view of this stop with shaft drive. Figure 7 is a bottom view of this stop with shaft drive. Figure 8 is a bottom view of the discharge station. In figure 1, reference number 1 shows a feed track for dry, pre-cooled poultry, which by means of the overhanger 3, which is, for example, of the type described in EP-A-0 155 014 in the name of applicants, is transferred to the conveyor track 5, in which the poultry moves in the direction of the arrows shown in the conveyor track. In the process, it passes first the grading station 7, in which it is grouped into grades, and this can be, for example, of the type used in the "Chickway 2/2" sorting system. After that, the poultry passes the weighing station 9, which can also be of the type used in the above-mentioned electronic sorting system, which is already known per se, use being made of a central computer which controls the operation of the various ejectors and overhangers. Reference numerals 11a - 11e indicate ejector stations by means of which poultry is ejected from the conveyor track 5 under the control of the signals transmitted by the central computer and falls into suitable collection containers for bulk packing; it is discharged via the discharge conveyor track 13. These ejector stations are also known from the Chickway system. Numbers 15, 17, 19 and 41 indicate overhangers of the type which are the subject of the present application, thus by means of which the poultry is discharged in a particular position. In stations 15 and 17 the poultry is discharged to packing stations 21 and 23 respectively, in which the poultry is packed by weight, while the transfer device 19 takes the poultry to a so-called jointing line 25, in which the poultry is jointed into separate portions suitable for consumption. Such a line comprises a number of processing stations, for example, of the type which are the subject of EP-A-0 159 076, EP 0 159 744, EP-A-0 159 745 and EP-A-0 164 167, all in the name of applicants. By means of discharge conveyor tracks, a number of which are shown and indicated by reference numerals 27, 29 and 31, the portions separated off in the processing stations of the jointing line are discharged and, for example, taken away in bulk (the discharge stations 33, 35) or separately in particular numbers packed by weight (the packing stations 37, 39). Finally, the conveyor track 5 passes the overhang device 41, in which certain poultry is discharged to a conveyor track 43, for undergoing yet other operations. Below, there will now follow a description of an embodiment of the device according to the invention, which is intended in particular for supplying poultry to the jointing conveyor track 25 in a particular position, i.e. in fact the design of the overhang device 19. Figure 2 shows schematically the supply conveyor track 5 for slaughtered poultry hanging by the legs from suitable suspension hooks 12, which are known per se. Also shown is the weighing station 9, in which the weight of the passing poultry, such as poultry 16, is determined in a manner known per se. It is assumed, for example, that if the weight of this poultry lies within a predetermined weight range, for example, between 1,000 and 1,400 grammes, the poultry has to be transferred to the jointing conveyor track 25, in which the poultry is jointed by a number of jointing stations into individual portions, each suitable for consumption. Other poultry has to be conveyed further by the conveyor track 5 in the direction of the arrow 20 to the next identical selective transfer station 41, in which it is transferred to another conveyor track (see Figure 1). As already stated, the poultry hangs at the track 5 by the legs on conveyance hooks: the conveyor track 25 is of the type in which the poultry is clamped by the legs between fixed guides 22, and carriers 24 cooperating therewith. The transfer station 19, in which this transfer from the conveyor track 5 to the conveyor track 25 is effected, comprises a fixed circular, annular track 28 having concentrically thereto a drive ring 32 which is driven continuously in the direction of the arrow 30, said two elements cooperating with the overhang hooks 34a . . . 34j, which are each guided by means of sets of bearing rollers 36 on the stationary outer ring 28 and by means of friction blocks 38 are slippingly driven by the rotating inner ring 32. The structure of these overhang hooks will be explained in details below. The device comprises an infeed station 40, preceded as seen in the direction of movement of the drive ring 32, by a stop 42, which is controlled by a pneumatic or hydraulic cylinder 44, and a discharge station 46, preceded as seen in the above-mentioned direction of movement, by a stop 48, which is controlled by the pneumatic cylinder 50. As can be seen from the figure there is, as seen in the direction of movement, between the discharge station 46 and the infeed station 40 a zone along which a number of hooks can accumulate, in this case the hooks 34a to 34g; there is also - looking in the direction of movement - between the infeed station 40 and the discharge station 46 a zone in which a number of hooks can accumulate, in this case the hooks 34i and 34j. The hooks 34a and 34b are retained by the stop 42, while the hooks 34h and 34i are retained by the stop 48; the other hooks are driven in slipping fashion and rest against each other. In order to ensure proper functioning of the device, there are a number of other elements, which will be described below in the explanation of the working device. The device operates as follows: When the weighing device 9 detects poultry whose weight falls within such a range that the poultry has to be discharged to the track 25, the weighing device 9 gives a signal to computing and selection device 54, which determines when the poultry in question, taking into account the speed of movement of the conveyor track 5, arrives at the infeed station 40, and which at the right moment at its output 54a transmits a control signal to the input 56a of the gate 58; the second input 56b of this gate 58 is connected to a suitable detector 60, disposed near the infeed station 40, which detector in the absence of a hook delivers a release signal to the second input 56b. When this release signal is present, the occurrence of a control signal at the input 56a will result in an output signal to the output 58c of the gate 58, which controls the control device 62, which results in the cylinder 44 being energized briefly. As a result, the hook 34a is released and the hook 34b moves up one place; the hook 34a is taken along by the ring 32 and arrives at the start of the infeed station 40 just when the hook 12 with poultry 16 arrives there. As will be explained below, the hook 34a takes over the poultry from the hook 16 because the fixed guide 41 presses the poultry out of the hook 12 into the hook 34a and is then transferred at a speed which is practically the same as that of the supply conveyor track 5 in the direction of the arrow 30 to the discharge station 46. Since the speed of the conveyor track 25 is lower than that of the conveyor track 5, there will thus always be overhang hooks with poultry in the zone upstream of the discharge station, and these hooks are released one by one by the stop 48 and pressed by a carrier, not shown in this figure, into the discharge conveyor track 25; this will be explained further. The stop 48 is controlled by the cylinder 50 by means of a control device 64, which is controlled from the gate 66, whose inputs 66a, 66b are connected to the conveyor tracks 25 and 28. The detector 70 transmits a release signal when there is no hook in front of it, in other words: when the zone downstream of the discharge station 46 is not completely full of empty hooks, and if this condition is met, the control signals at the input 66a will operate the control device 64 and then the actuating cylinder 50, so that the poultry-carrying hooks are conveyed one by one before the conveyor track 25. The poultry is then removed from the hook, fed into the conveyor track, and discharged in the direction of the arrow 72. Figure 3 shows a bottom view of the transfer station 26. The figure shows the supply conveyor track 5 with thereon the hooks 12; the conveyor track moves in the direction of the arrow 20. Disposed shortly before the infeed station 40 is a guide bracket 11, which is for preventing the pushing away of the hooks 12 during removal of the poultry. If the hook 34a directly in front of the infeed station 40 is then released by the stop 44 operated by actuating cylinder 42, this hook will take over the poultry from the hook 12 and convey it in the direction of the arrow 30 to the discharge station 46. Upstream of this discharge station is a guide bar 45 which ensures that the poultry remains properly in the hook directly in front of the discharge station 46 until the moment of discharge, in this case that it remains in the hooks 34j and 34i, and is not slung out. The discharge of the poultry from the discharge station 46, and the transfer thereof to the discharge conveyor track 25 take place under the influence of carriers which are fixed between the endless chains 47a, 47b, one of which is shown by reference numeral 49, and is partially visible in Figure 8. The linear speed of the chains 47a, 47b is about one and a half times that of the discharge conveyor track 25, so that it is ensured that poultry brought in is always taken in front of the inlet of the conveyor track 25 before the arrival of the pushing and retaining element of this track. Figure 4 shows schematically the stationary annular conveyor track 28, fixed by means of carrier arms 29a to a central carrier 31a, which is supported by a frame 33a; supported in a central bearing box 35a is the end of a shaft 37a, which at the top side is supported in a bearingbox 39a, and is provided with a drive gear 41a. Fixed on the shaft 37a is a carrier 43a with arms 45a, on the end of which the drive ring 32 is fastened. The design of the overhang hooks can be seen from Figures 5a and 5b. The hook, shown in its entirety by reference numeral 34, consists of a plate-like element 80, with infeed and guide grooves 82, 84, separated from each other by an asymmetrical, wedge-shaped intermediate part 86; the plate-shaped part is fixed to the carriage 88, which bears the two parts of guide rollers 90a, 90b and 92a, 92b, which cooperate with the annular conveyor track 28. The carriage 88 also bears on the righthand open side two friction blocks 94a, 94b, which are opposite each other, and the latter of which is under the influence of the pressure spring 96; the friction blocks are on either side of the driving track 32. These friction blocks under a spring ensure slipping drive of the overhang hook 34. Each overhang hook 34 bears a stop boss 98, which is also seen in Figure 6b, this figure in conjunction with Figure 6a showing the operation of the controllable stops 42, 48. Each controllable stop, such as the stop 48, has a tilting arm 48a which can rotate about the fixed pivot point 51 and on each of the ends bears a stop pin 53a, 53b. The piston rod 55 of the actuating cylinder 50 is connected in the eccentric hinge point 57 to the arm 48a, while the cylinder 50 is itself hingedly connected to the stationary part 31a at the point 59. The effect of these measures is that on brief expansions and retraction of the piston rod 55 the overhang hook retained by the pin 53b (in Figure 8 the overhang hook 34h) and the overhang hook retained by the pin 53a (in Figure 8 the overhang hook 34i) are both released; the hook 34i moves further in the direction of the arrow 30 and is retained by the pin 53b, in the position for the overhanging of poultry hanging in the hook in the conveyor track 25, while the hook 34j also moves up a position and takes over the position which was previously held by the hook 34i. The released empty hook moves to the stop 42 and comes to rest against a foregoing hook. Figure 8 shows also the chain 47b, which together with the chain 47a bears the carrier 49, for pressing out of the discharge station the bird hanging in the hook 34h, for bringing it into the infeed section 18a of the discharge conveyor track 25. This conveyor track forms no part of the invention and will not, therefore, be described in detail. Finally, Figure 7 shows on an enlarged scale a part of the infeed station with the actuating cylinder 42, whose piston rod 61 and 63 is linked to the tilting arm 65, which like the tilting arm 48a, is provided with two stop pins, one of which can be seen and is indicated by reference numeral 67. After the above, the operation thereof needs no further explanation.

Claims: Device for the selective transfer of slaughtered poultry, supplied on a conveyor track (5), to one or more discharge stations, under control of at least one grading station (7, 9) disposed along the conveyor track (5), each discharge station comprising a control device for removing from the conveyor track (5) poultry selected by the grading station (7, 9) for the particular discharge station, and a buffer device in which the poultry to be transferred can be temporarily stored, characterized in that the device comprises a second conveyor track (25), and in that the buffer device comprises an infeed station (40) cooperating with the first conveyor track (5), a discharge station (46) cooperating with the second conveyor track (25) and an endless transfer track (28) accommodated between the infeed station (40) and the discharge station (46), the endless transfer track having guided along it transfer hooks (34a...34j) which can either stop or be driven along the transfer track (28), while in the direction of movement (30) along the transfer track (28) in front of both the infeed station (40) and the discharge station (46) there is sufficient space for the accumulation there of a number of empty and poultry-carrying transfer hooks respectively (34a ... 34j), and a first stop (42), controlled by the grading station (7, 9), is arranged for the release one by one of empty transfer hooks (34a ... 34j) to a position for cooperation with the first conveyor track (5) for removal of poultry from the first conveyor track (5), and a second stop (48) is arranged for the release of the poultry-carrying transfer hooks (34a ... 34j) to a position for cooperation with the second conveyor track (25) for removal of poultry from the transfer hooks (34a ... 34j). Device according to claim 1, characterized in that the transfer track (28) is designed as a fixed circular first ring (28), coaxial with a rotary driven second ring (32), and the transfer hooks (34a ... 34j) are guided on the first ring (28) and are provided with friction blocks (94a, 94b) for cooperating with the second ring (32). Device according to claim 1 or 2, characterized in that in the first conveyor track (5) the poultry is moved along hanging by the legs from suspension hooks (12), and in the second conveyor track (25) is moved along with the legs clamped against fixed guides (22), the plate-shaped transfer hooks (34a ... 34j) are designed with take-up slots (82, 84), the first conveyor track (5) at the infeed station (40), where the poultry is pressed by a guide (41) disposed along the first conveyor track (5) out of the suspension hooks (12) into the transfer hooks (34a ... 34j), is tangent to the transfer track (28), and the second conveyor track (25) at the discharge station (46), where the poultry is pressed by an ejector from the transfer hooks (34a ... 34j) between the second conveyor track guides (22), is at right angles to the transfer track (28). Device according to any of claims 1-3, characterized by detectors (60, 70) disposed along the transfer track (28), for determining the number of transfer hooks (34a ... 34j) accumulated in front of the infeed station (40) or discharge station (46), while a control device for the first (42) and second stop (48) is designed in such a way that the first stop (42) cannot be released when the number of hooks accumulated before the second stop (48) exceeds a particular value, and the second stop (48) cannot be released when the number of hooks accumulated in front of the first stop (40) exceeds a predetermined value. Device according to any of claims 2-4, characterized in that each stop (40, 48) has a tilting arm (48a) which hinges about a shaft (51) which is parallel to the rotary shaft of the second ring (32), said arm being designed with two spaced stops (53a, 53b), each cooperating with a boss (98) on each of the transfer hooks (34a ... 34j). Device according to any of claims 1-5, characterized in that the grading station (9) is formed by a weighing device.

Inventors: BRAKELS, GERARDUS HUBERTUS MARIA, VAN DEN NIEUWELAAR, JOSEPHUS ADRIANUS
Applicants: STORK PMT B.V.
Application year: 1987
Main classification: A22C21
IPC codes: B65G47, A22C5, B65G37, A22C21