Method for Handling Individual Parts, Handling Systems, and Grouping Unit
20220379532 · 2022-12-01
Inventors
- Roland Wandura (Limburgerhof, DE)
- Andreas Wild (Bretten, DE)
- Jochen Hörne-Höhl (Stutensee-Friedrichstal, DE)
Cpc classification
B29C45/42
PERFORMING OPERATIONS; TRANSPORTING
B29L2031/7544
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A handling system and/or a grouping unit of a handling system and a method for handling individual parts that have to be removed from a preceding production process, in particular injection-molded parts in the form of pipette tips that are produced in groups in an injection molding machine with a multiple tool and must be removed from the multiple tool for the further handling, the multiple tool including at least one distributing star having a plurality of mold cavities, whereby a removal arrangement is defined by the multiple tool for the further handling of the injection-molded parts. The method includes removing the finished injection molded parts, loading the parts into a grouping unit to produce a grid arrangement, and removing the parts from one grouping unit with a second grouping unit.
Claims
1. A method for handling individual parts which have to be removed from a preceding production process, in particular injection molded parts in the form of pipette tips (2), which are produced in large numbers in an injection molding machine (3) using a multi-cavity mold (4) and have to be removed from the multi-cavity mold (4) for further handling, wherein the multi-cavity mold (4) has at least one radial runner system with a plurality of mold cavities, whereby a removal assembly is provided by the multi-cavity mold (4) for further handling of injection molded parts, the method comprising: a) removing the finished injection molded parts from all existing mold cavities of the multi-cavity mold (4) at once in a single method step and delivered to a transfer unit (13), which, in the subsequent course of the method, transfers the injection molded parts into a first grouping unit (14), b) loading the injection molded parts into the first grouping unit (14) in the form of a two-dimensional grid, wherein the grid has at least two rows each with two injection molded parts, c) when loaded, moving with the first grouping unit (14) the injection molded parts of parallel mutually adjacent rows (R1, R2) toward one another, so as to produce a more compact grid arrangement of the injection molded parts in a first coordinate direction, d) then removing the injection molded parts from the first grouping unit (14) with a second grouping unit (24), wherein the distance between the rows in the second coordinate direction is likewise reduced using the second grouping unit (24), so as to produce a more compact, tighter grid in both coordinate directions.
2. The method according to claim 1, wherein the removal assembly specified by the multi-cavity mold (4) for the injection molded parts has a regular convex polygon with an even number (n) of vertices on a circumcircle (7, 8, 42, 44, 46, 48, 50, 52), wherein the injection molded parts lie at the vertices of the polygon with a midline C that divides the number of injection molded parts symmetrically and in the case of a number greater than four vertices/injection molded parts the following intermediate step is performed between method steps a) and b): a.sub.1) moving innermost injection molded parts relative to the midline (C) are moved outward until they are aligned in the same line with the outlying injection molded parts, such that two parallel rows (R1, R2) are formed from all (n) injection molded parts.
3. The method according to claim 2, wherein the midline (C) is defined in the first grouping unit (14) and/or in the second grouping unit (24), which midline lies symmetrically between the parallel adjacent rows of injection molded parts, and in that the adjacent rows of injection molded parts are moved symmetrically toward the midline (C).
4. A handling system (1) for injection molded parts which have to be removed from a multi-cavity mold (4), which multi-cavity mold (4) includes at least one radial runner system with a plurality of mold cavities and whereby a removal assembly for further handling of the injection molded parts is predetermined, wherein the handling system comprises: a removal unit (6), a transfer unit (13), and at least one first grouping unit (14), and a second grouping unit (24); and wherein a grid arrangement with Cartesian coordinates is produced, in which the grid dimension is reduced in both coordinate directions, wherein each of the grouping units (14, 24) has separate transversely mobile support strips (16, 25), in that the support strips (16, 25) are coupled via a linear bearing arrangement to at least one guide rail (18, 20, 21), and wherein an individual movement path with individual movement end points is provided for at least some of the support strips (16, 25), and in that at least one pusher element (32) is provided, with which at least one of the support strips (16, 25) is movable to and fro between its individual movement end points.
5. The handling system for injection molded parts according to claim 4, wherein in the case of a removal assembly which is based on a multi-cavity mold (4) with an even number of more than four mold cavities per radial runner system, the transfer unit (13) includes a repositioning device (51) with which a two-row grid arrangement of 2×3, 2×4, 2×5 or 2×6 injection molded parts can be produced from a polygonal arrangement distributed uniformly around a circumcircle (42, 44, 46, 48, 50, 52), wherein for the polygon of the removal assembly a midline (C) is defined which divides the injection molded parts symmetrically into two groups of equal numbers, wherein the midline (C) is arranged such that none of the injection molded parts lies directly on the midline (C) but rather all the injection molded parts are spaced from the midline (C), wherein the furthest outlying injection molded parts relative to the midline (C) define the position of parallel outer lines, wherein a base element (54) is provided which has stationary receiving elements (S1, S2, S3, S4) for the injection molded parts lying on the outer lines, and wherein for all the other injection molded parts mobile receiving elements (63, 64, 65, 66, 67, 68, 69, 70) are provided in order to move them, divided symmetrically, toward the outer lines and produce a two-row grid arrangement.
6. A grouping unit (14, 24) for use in a handling system, the grouping unit comprising: at least two support strips (16, 25) in each case for receiving one row of injection molded parts; at least one guide rail (18, 20, 21, 26, 27, 28), wherein each support strip (16, 25) is coupled by a linear bearing arrangement to at least one guide rail (18, 20, 21, 26, 27, 28) such that the support strips (16, 25) are coupled to the guide rail (18, 20, 21, 26, 27, 28) so as to be movable transversely of their longitudinal direction using the linear bearing arrangement, in that a closed state of the support strips (16, 25) is provided with minimum spacing of the support strips (16, 25) relative to one another, and a spread-out state of the support strips (16, 25) is provided in which a greater spacing is provided between the support strips (16, 25) which corresponds to the grid dimensions of arriving injection molded parts.
7. A grouping unit according to claim 6, further comprising at least one pusher element (32) configured to provide simultaneous translational drive of a plurality of support strips (16, 25), which support strips have individual movement distances between their position in the closed state and their position in the spread-out state.
8. The grouping unit according to claim 7, further comprising a projecting driver element (37) associated with each support strip (16, 25), which driver element interacts with pairs of pusher faces (33, 34, 35, 36) of the pusher element (32), and in that the distance present in the movement direction between the pusher faces of one pair is in each case adapted to the individual movement distance for the mobility of the corresponding support strip (16, 25) between its position in the closed state and its position in the spread-out state.
9. The grouping unit according to claim 7, wherein a stroke of the at least one pusher element (32) corresponds to a movement distance of that support strip (16, 25) which has to travel the greatest distance between its position in the closed state and its position in the spread-out state.
10. The grouping unit according to claim 7, wherein two pusher elements (32) are provided and two groups of support strips (16, 25) are symmetrically movable.
11. The grouping unit according to claim 7, wherein the support strips (16, 25) are arranged upright on the guide rail (18, 20, 21) or are arranged suspended from the guide rail (26, 27, 28).
12. The grouping unit according to claim 11, wherein upright arranged support strips (18, 20, 21) include a row of receiving openings (10) such that in each case one injection molded part is receivable into one receiving opening, or suspended support strips (26, 27, 28) include receiving elements (19) via which injection molded parts are vacuum-couplable as a vertically movable load.
13. (canceled)
14. (canceled)
15. The handling system according to claim 4, wherein the support strips (16, 25) are configured to be movable transversely of their longitudinal direction using the linear bearing arrangement such that in a closed state, the support strips (16, 25) are configured with minimum spacing of the support strips (16, 25) relative to one another, and in a spread-out state, the support strips (16, 25) are configured in which a greater spacing is provided between the support strips (16, 25) which corresponds to the grid dimensions of arriving injection molded parts.
16. The handling system according to claim 15, the at least one pusher element (32) is configured to provide simultaneous translational drive of a plurality of support strips (16, 25), which support strips have individual movement distances between their position in the closed state and their position in the spread-out state.
17. The handling system according to claim 16, wherein the at least one first grouping unit and/or the at least one second grouping element includes a projecting driver element (37) for each support strip (16, 25), which driver element interacts with pairs of pusher faces (33, 34, 35, 36) of the pusher element (32), and in that the distance present in the movement direction between the pusher faces of one pair is in each case adapted to the individual movement distance for the mobility of the corresponding support strip (16, 25) between its position in the closed state and its position in the spread-out state.
18. The handling system according to claim 16, wherein a stroke of the at least one pusher element (32) corresponds to a movement distance of that support strip (16, 25) which has to travel the greatest distance between its position in the closed state and its position in the spread-out state.
19. The handling system according to claim 16, wherein there are two pusher elements (32), and two groups of support strips (16, 25) are symmetrically movable.
20. The handling system according to claim 16, wherein the support strips (16, 25) are arranged upright on the guide rail (18, 20, 21) or are arranged suspended from the guide rail (26, 27, 28).
21. The handling system according to claim 20, wherein upright arranged support strips (18, 20, 21) include a row of receiving openings (10) such that in each case one injection molded part is receivable into one receiving opening, or suspended support strips (26, 27, 28) include receiving elements (19) via which injection molded parts are vacuum-couplable as a vertically movable load.
22. The handling system according to claim 16, wherein the support strips (16, 25) are arranged upright on the guide rail (18, 20, 21) and include a row of receiving openings (10) such that in each case one injection molded part is receivable into one receiving opening.
Description
[0044] The invention is illustrated below by way of example in drawings and described in detail with reference to several figures, in which:
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[0066] For further handling, these injection molded parts (pipette tips) must be removed from the multi-cavity mold 4, wherein the multi-cavity mold has at least one radial runner system with a plurality of mold cavities, whereby a removal assembly is fixedly specified by the multi-cavity mold 4 for further handling of these injection molded parts.
[0067] Right at the end of the handling steps, the pipette tips should be arranged compactly and be capable of being delivered to a finished part holder 5. The injection molding machine 3 and the finished part holder 5 are depicted in
[0068] The multi-cavity mold contains a systematic arrangement of the mold cavities. According to
[0069] The removal unit 6 serves to transfer all 64 pipette tips in the stated vertical array out of the multi-cavity mold 4. In the present example, the multi-cavity mold is formed of two mold parts 4a and 4b. The two mold parts may open and close at a vertical parting plane. To this end, one mold part 4a is arranged stationarily and the other mold part 4b movably, so as by this movement to bring about opening and closing of the multi-cavity mold 4.
[0070] The removal unit 6 is moved toward the multi-cavity mold 4 when the latter is opened, in order then to accept finished produced pipette tips 2.
[0071] On its stationary mold part 4a, the multi-cavity mold comprises a mandrel 9 for each pipette tip, which mandrel is part of the mold cavity and serves to shape the inner contour of the pipette tip 2. When the multi-cavity mold 4 is in the open state, finished injection molded pipette tips may initially remain on the projecting mandrel 9 and are then pushed down from the mandrel using an ejector (not shown) and into receiving openings 10, which are provided in the removal unit 6. The removal unit is moved for this purpose between the open mold parts into an exact position in which their receiving openings and the mandrels of the multi-cavity mold are brought exactly into congruence. Then the ejector is actuated to push the pipette tips 2 off the mandrels 9 in the direction of the receiving openings 10 of the removal unit 6. The ejector stroke is of such magnitude that in each case the free end of the pipette tip can be moved somewhat into the receiving opening with one ejection stroke. Acceptance of the pipette tips is assisted by providing the removal unit 6 with a suction air device (not shown). The suction air device is connected with the receiving openings 10 and may, if need be, generate in the receiving openings 10 a negative pressure relative to the ambient pressure, to attach the pipette tips 2 by suction and hold them firm.
[0072] When the removal unit 6 is loaded with the pipette tips 2, it retains its vertical orientation and is moved out of the region of the injection molding machine 3. In the present exemplary embodiment, a linear guide 11 and a linear motor 12 are provided for moving out the removal unit. The removal unit 6 can thus not only be moved in a precisely positioned manner into the multi-cavity mold 4, but also moved out when loaded and conveyed to a transfer unit. At the same time, the removal unit 6 continues to retain its vertical orientation.
[0073] The object of the transfer unit 13 illustrated in
[0074] To this end, the transfer unit 13 is provided with transfer mandrels 15 for each pipette tip 2. The transfer mandrel fits in each case into the opening in the pipette tip. Furthermore, a movement device is assigned to move the transfer mandrels 15 into the openings in the pipette tips 2. With the pipette tips situated thereon, the transfer mandrels 15 are moved in the opposite direction fully out of the receiving openings 10 of the removal unit. So that the pipette tips 2 are firmly held on the transfer mandrels, the latter are connected to a suction air device (not shown). If need be, the suction air device generates a negative pressure relative to ambient pressure. The negative pressure sucks the pipette tip onto the transfer mandrel 15 and holds it firmly thereon.
[0075] The array of pipette tips 2 is then rotated out of their vertical orientation into a horizontal orientation. Each transfer mandrel 15 is then oriented suspended vertically downward and the pipette tips 2 are firmly held suspended on the transfer mandrels 15 using the connected suction air device, which generates an appropriate negative pressure.
[0076] Below the horizontally oriented array of pipette tips is located the stated first grouping unit 14, which has eight support strips 16 next to one another, wherein in each support strip a row of eight receiving openings 17 is provided for pipette tips 2. In this case, the receiving openings 17 of all the support strips are arranged congruently with the horizontally oriented array of pipette tips 2 still located in the transfer unit. In order to transfer the pipette tips into the receiving openings 17 of the support strips 16 of the first grouping unit 14, the suction air device is switched off. Either the pipette tips fall down and into the receiving openings 17 or the transfer unit 13 is lowered until the pipette tips project somewhat into the receiving openings 17, the suction air device then being switched off and the pipette tips being received securely in the receiving openings 17.
[0077] The first grouping unit 14 receives pipette tips only when they are already present in a row arrangement with an identical number of pipette tips per row, as in the exemplary embodiment in
[0078] If, on the other hand, the multi-cavity mold has radial runner systems with mold cavities in a 6-sided, 8-sided, 10-sided or 12-sided polygonal arrangement, then this arrangement must firstly be changed into a two-row arrangement with 2 rows each with 3 pipette tips (2×3) or 2×4, 2×5 or 2×6 pipette tips. To this end, a further developed transfer unit is proposed further below with reference to
[0079] The first grouping unit 14 is shown separately in
[0080] Each support strip 16 of the first grouping unit 14 is mounted in each case by way of a pair of guide rails 18 and on the guide rails a pair of guide carriages 19 is arranged. The ends of the support strip are connected with the respective guide carriage 19. In the present exemplary embodiment, overall three pairs of guide rails 18, 20 and 21 are provided, although in principle one pair could suffice for all the support strips. In the present case, however, this would disadvantageously lead to the support strips 16 not being able to be moved as close together as desired. The reason for this lies in the size of the available guide carriages 19. If the guide carriages of all the support strips were to run on just one guide rail, then the size of the guide carriages 19 would specify how close the support strips 16 could be pushed together. Since the support strips are narrow, excessively large gaps would arise between the individual support strips. This is remedied by providing the stated three pairs of guide rails 18, 20 and 21, which allows the outer, longer support strips to be provided with cutouts for the guide carriages 19 of the adjacent inner support strips. In this way, it is ensured that the guide carriages of the inner support strips have space and can pass through the cutout in the longer support strips. In this manner, all the support strips 16 can be moved really close together.
[0081] As is clear from looking at
[0082] In
[0083] Movement of the support strips 16 is driven in a particular way, as is described further below with reference to
[0084] Firstly, however, the next method step is explained with which the pipette tips 2 are likewise compactly arranged in a second direction. For this purpose, the handling system 1 is provided with a second grouping unit 24, which is depicted in
[0085] To this end, the second grouping unit 24 in turn also has eight support strips 25, which are mounted movably on pairs of guide rails. Here too, three pairs of guide rails 26, 27 and 28 are provided. The principle of operation of the second grouping unit 24 is largely identical to the principle of operation of the first grouping unit 14. There is a difference in that, in the first grouping unit 14, the pipette tips 2 are arranged within receiving openings of the support strips, while the second grouping unit 24 is set up so to speak to lift the pipette tips 2 in each case using a downwardly projecting receiving element 29 which extends into the opening of the pipette tip 2. The support strips 25 of the second grouping unit 24 are to this end arranged suspended on the associated pair of two guide rails, as can best be seen from
[0086] The suspended support strips 25 of the second grouping unit 24 are arranged in the handling system offset by 90° relative to the support strips of the first grouping unit 14. The grid arrangement of 8×8 pipette tips, already moved together compactly with the first grouping unit in one direction, is moved together compactly with the suspended support strips 25 in the second direction, as shown in
[0087] The 8×8 pipette tips moved together compactly in two directions are then delivered by the second grouping unit 24 into a finished part holder, as shown in
[0088] How the movement of the support strips of the two grouping units is driven is described below with reference to
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[0091] When the support strips 25 move apart from the closed state into the spread-out state, once the first, inner support strip has reached its limit/end stop, the remaining three support strips 25 have to continue moving. Once the second support strip 25 has reached its end stop, the third and fourth support strips 25 have to continue moving, and as soon as the third support strip 25 reaches its limit/end stop, just the fourth support strip 25 continues moving on to its end stop.
[0092] To implement the above-described movement of the support strips mechanically, adjoining movement paths 33a, 34a, 35a are provided with individual movement end points for the support strips, specifically in the form of pusher face pairs 33, 34, 35 and 36 respectively.
[0093] The pusher faces of the pusher face pairs are in each case aligned facing one another and define the ends of the corresponding movement path. The movement paths are oriented parallel to the translational direction of movement of the pusher element 32.
[0094] A driver element 37, which interacts with the associated pusher face pairs of the pusher element 32, is arranged on each support strip 25. Depending on the direction of movement, the driver element 37 is pushed by one or the other pusher face in the corresponding direction.
[0095] For the outlying support strip 25, which has to travel the furthest distance between the spread-out and closed states, the pusher face pair is configured as a hole 36a in the pusher element 32. The two pusher faces lie close to one another in the hole. This is the case because the maximum stroke of the pusher element 32 corresponds to the distance by which the outlying support strip 25 has to be moved between the spread-out and the closed states.
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[0097] If more than four support strips are provided per symmetrical side, these may be moved using a correspondingly adapted pusher element, which has additional pusher face pairs for each additional support strip.
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[0100] According to
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[0102] In order to be able to bring about the above-described two-row arrangement of injection molded parts, the transfer unit is further developed. To this end, the transfer unit is provided with a repositioning device, which can modify the position of specific injection molded parts. A correspondingly further developed transfer unit or the repositioning device thereof is explained further below with reference to
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[0107] The transfer unit proposed above is therefore further developed and specifically provided with a specific repositioning device 51, which may change the spatial arrangement of the injection molded parts in order to bring them into a two-row arrangement. The present further developed transfer device is based on a removal assembly, which corresponds in principle to the example of
[0108] A vertical midline C runs in each case through a radial runner system of the upper row L1 and a radial runner system of the lower row L2. Each radial runner system has four receiving elements 53 for injection molded parts provided in each case to the left of the midline C and likewise four receiving elements 53 for injection molded parts to the right of the midline C.
[0109] The repositioning device has a base element 54. The receiving elements 53 for those injection molded parts which do not have to be shifted, namely the outlying receiving elements 53 located in rows R1 and R2, are arranged stationarily on the base element.
[0110] Furthermore, the other four receiving elements of the repositioning device are mobile, namely those which, according to
[0111] To obtain the mobile receiving elements of the repositioning device, pusher rods 55, 56, 57, 58, 59, 60, 61 and 62 are provided, which are capable of pushing the mobile receiving elements. Those mobile receiving elements which are identically aligned and have to be moved in the same direction interact with the same pusher rod. This applies, for example, to the mobile receiving elements 59, 60, 61 and 62 in row L2, which interact with the pusher rod 61 and have to be moved in the direction of arrow M. However, mobile receiving elements 67, 68, 69 and 70 identically aligned in row L2 are also present which have to be moved in the opposite direction, that of arrow N, and for this purpose are connected with pusher rod 62, which is moved in the direction of arrow N.
[0112] For the pusher rods 56, 58, 60 and 62, coupling is provided via a coupling element 71 which connects these pusher rods together and moves them in the same direction. One receiving element, with the same direction of movement, from each radial runner system is connected to each of these pusher rods. A pneumatic cylinder 72 is provided on the coupling element 71 for joint drive of the pusher rods 56, 58, 60 and 62.
[0113] The other pusher rods 55, 57, 59 and 61 are likewise connected together via a coupling element 73 for the purpose of being jointly driven. A piston rod 74 of the pneumatic cylinder 72 is connected to the coupling element 73. For correct positioning of the receiving elements which are movable to and fro, limit stop elements are provided on the pusher rods, such as for example limit stop element 75 on pusher rod 56. One limit stop element is sufficient per pusher rod for each direction of movement. The limit stop element then interacts with one of the receiving elements of these pusher rods. None of the other receiving elements needs its own limit stop elements.
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[0115] In
LIST OF REFERENCE SIGNS
[0116] 1 Handling system [0117] 2 Pipette tip [0118] 3 Injection molding machine [0119] 4 Multi-cavity mold [0120] 4a Mold part (stationary) [0121] 4b Mold part (mobile) [0122] 5 Finished part holder [0123] 6 Removal unit [0124] 7 Circumcircle [0125] 8 Circumcircle [0126] 9 Mandrel [0127] 10 Receiving opening (removal unit) [0128] 11 Linear guide [0129] 12 Linear motor [0130] 13 Transfer unit [0131] 14 First grouping unit [0132] 15 Transfer mandrel [0133] 16 Support strip [0134] 17 Receiving opening (support strip) [0135] 18 Guide rail (pair) [0136] 19 Guide carriage (pair) [0137] 20 Guide rail (pair) [0138] 21 Guide rail (pair) [0139] 22 Outer limit stop [0140] 23 Limit stop element [0141] 24 Second grouping unit [0142] 25 Support strip [0143] 26 Guide rail [0144] 27 Guide rail [0145] 28 Guide rail [0146] 29 Receiving element [0147] 30 Outer limit stop [0148] 31 Limit stop element [0149] 32 Pusher element [0150] 33 Pusher face pair [0151] 33a Movement path [0152] 34 Pusher face pair [0153] 34a Movement path [0154] 35 Pusher face pair [0155] 35a Movement path [0156] 36 Pusher face pair [0157] 36a Hole [0158] 37 Driver element [0159] 37a Driver foot [0160] 37b Driver head [0161] 38 Hole (support strip) [0162] 39 Radial runner system [0163] 40 Radial runner system [0164] 41 Injection molded part [0165] 42 Circumcircle [0166] 43 Injection molded part [0167] 44 Circumcircle [0168] 45 Injection molded part [0169] 46 Circumcircle [0170] 47 Injection molded part [0171] 48 Circumcircle [0172] 49 Injection molded part [0173] 50 Circumcircle [0174] 51 Repositioning device [0175] 52 Circumcircle [0176] 53 Receiving element [0177] 54 Base element [0178] 55 Pusher rod [0179] 56 Pusher rod [0180] 57 Pusher rod [0181] 58 Pusher rod [0182] 59 Pusher rod [0183] 60 Pusher rod [0184] 61 Pusher rod [0185] 62 Pusher rod [0186] 63 Receiving element [0187] 64 Receiving element [0188] 65 Receiving element [0189] 66 Receiving element [0190] 67 Receiving element [0191] 68 Receiving element [0192] 69 Receiving element [0193] 70 Receiving element [0194] 71 Coupling element [0195] 72 Pneumatic cylinder [0196] 73 Coupling element [0197] 74 Piston rod [0198] 75 Limit stop element [0199] 76 Limit stop element [0200] C Midline [0201] L1 Row [0202] L2 Row [0203] M Arrow [0204] N Arrow [0205] P1 Pneumatic cylinder [0206] R1 Row [0207] R2 Row [0208] S1 Mobile receiving element [0209] S2 Mobile receiving element [0210] S3 Mobile receiving element [0211] S4 Mobile receiving element P1