WO2009133580A1

WO2009133580A1 - Apparatus for forming packs of plastic bags

Info

Publication number: WO2009133580A1
Application number: PCT/IT2009/000099
Authority: WO
Inventors: Gianfranco Galimberti
Original assignee: I.P.S. S.R.L. International Project Services
Priority date: 2008-04-28
Filing date: 2009-03-17
Publication date: 2009-11-05

Abstract

An apparatus for forming packs of plastic bags (S) or the like presenting holes - in particular two holes (F) - along one edge. This apparatus comprises a multiple reel which presents the bags singularly to a transferring chain (7, 9) for transferring packs of bags (Sp) accumulated in needles (9) - individual or in particular pairs of needles - present in succession on the chain (7). On this latter the individual needles (9) are mounted in such a way so that they can be adjusted in position (9A), so as to guarantee the picking-up of the bags which they have to perform for the transferring also in the case of lateral movement of the bag.

Description

"APPARATUS FOR FORMING PACKS OF PLASTIC BAGS"

DESCRIPTION Technical Field

The apparatus according to the present invention is of the type for forming packs of plastic bags or the like presenting holes (in particular two holes) along one edge. State of the art

Apparatuses are known for forming packs of plastic bags or the like provided with one or more holes (in particular two holes) along one edge, that comprise, according to a known structure, a multiple reel which presents the individual bags singularly to a transfer chain for transferring packs αf bags accumulated in needles (especially couples of needles) present in succession on the chain.

Once the packs have been formed on the needles, they are picked up. In order to avoid the packs being "separated" during handling, they are bound with rope or iron wire which is made pass through the holes.

In those apparatuses, all the set forming the conveyor of the chain (included the bearing structure) must be continuously adjusted transversely, so as to follow the instantaneous irregularities of the position in which are the bags reaching the position of insertion onto the needles; this requires energy for displacement of significant masses with high inertia. Object and summary of the invention

The object of the present invention is to solve the problems described above related to the handling of the chain conveyor so as to allow centering of the packs by means of the needles. £

This and other objects, which will be better described hereunder, are achieved through the invention, according to which the individual needles are mounted on said chain in such a way as they can be varied in position, so as to guarantee the picking-up of the bags they have to transfer, although maintaining the structure of said transferring chain fixed.

These needles can be constrained to the chain so as to be translated and / or inclined angularly relative to the chain.

Suitably, the present invention comprises members for common engagement of the bags arranged at correspondence of the pairs of needles . .

which allow easy collection, transport and handling of the packs which have been formed. These engaging members are suitable to follow the variation of position of the needles for inserting the bags. In practice, these engaging members are also transferring members for transferring the bags. Downstream of said transferring chain a picking-up device of the engaging members is provided with the packs of bags engaged in the members, thus allowing handling of the packs. The picking-up device can be designed so as to perform an active stroke for transferring the packs of bags from the transferring chain to a removing system. This picking-up device can be used for bringing the engaging members from a warehouse to the corresponding pair of needles.

According to a preferred embodiment of the present invention, opposite seat are defined between the needles for engaging members constituted by U - shaped members arranged in said seats. In practice, to each pair of needles corresponds a U - shaped member destined to engage the packs of bags which are accumulated there by means of the holes present in the same bags; these U - shaped members allow easy handling of the packs of bags.

The above mentioned seats can be channel - developed, where the U - shaped members are held thanks to the effect of a limited elastic deformation. In a preferred embodiment of the present invention, adjusting means are present for adjusting the reciprocal distance of the needles so as to adapt the chain to the handling of types of bags provided with pairs of holes with different center - to - center.

As regards this adjustment of the reciprocal distance of the needles, another preferred embodiment of the present inventions provides for the engaging members to be constituted by sleeves which are arranged on the needles (so as the latter result inserted in them), one for each needle, before arrangement of the sacks. These sleeves present lower abutment means projecting laterally. The bags are so stacked on these sleeves (one per hole); the packs formed rest on lower abutment means of the sleeves. It is therefore possible to pick up the packs by taking them from the head of the sleeves, preventing the removal thereof from the sleeves.

Advantageously, with reference to this latter embodiment, the sleeves present at the top anti - extracting means. - o -

Preferably, these anti - removal means comprise, for each sleeve, a cap snap coupleable on the head of the sleeve and provided with a portion laterally projecting relative to the outer diameter of the sleeve that prevents in this manner the extraction of the bags from the top. Brief description of the drawings

The invention shall now be better understood by following the description and the accompanying drawings, which show non-limiting practical embodiments of the invention. In the drawings, figure 1 shows an overall side view of the apparatus according to the present invention; figures 2A and 2B show a view and a section according to H-Il of figure 1 , in two variants of embodiments; figure 3 is a section according to Ill-Ill of figure 1 ; figure 4 is an enlarged partial view of figure 1 , illustrating a segment of the path of the transferring chain; figures 5 and 6 show a section according to V-V of figure 4, in two variants of embodiment; figures 7 and 8 show a partial side view of the transferring chain and a section according to VIII-VIII of figure 7; figure 9 shows a cross section of the transferring chain, in the feeding area for feeding the bags to the chain; figure 10 shows an individual bag combined with a stacking and transferring U - shaped member; figures 11 and 12 show individually a U - shaped stacking and transferring member, in side view and section according to XII-XII of figures 7 and 11; figure 13 is a front section view of a pack of bags arranged on a stacking sleeve suitable for its handling; figure 14 is a side section view of the pack of bags of figure 13 with the corresponding sleeves; figure 15 shows a side view of a portion of the apparatus according to the present invention in a different version from that of figures 1 to 12, related to the use of stacking and transferring sleeves for the packs of bags; figures 16 and 17 show cross sections of the apparatus, where are visible the phases of actuation ofmembers for loading the sleeves on the chain and for transferring the formed packs.

Detailed description of embodiments of the invention

According to what is illustrated in the figures, the arrow f1 indicates an entrance path of the material M destined to the formation of bags S in plastic film; the arrow f2 indicates the welding and cutting area for forming from the material M the bags S (see figure 10) with their edge perforated with two holes F necessary for the various handling; the bags S are individually positioned on a series of at least two or more coaxial multiple arm reels 5 , suitable to receive the individual bags S; each of the bags S is held by means of suction and transferred to a position Sa (figure 1), where each subsequent bag is released due to the termination of the pneumatic retaining. In this position Sa the released bag shall be engaged by a transferring chain 7 for horizontal transferring, which is provided, for this purpose, with a multiplicity of pairs of needles 9 and is provided with an intermittent forwarding according to the arrow f7a and with a return according to the arrow f7b; said chain 7, 9 shall stay in an intermittent stop so as to receive and accumulate on the needles 9, which are in the position 9A, a desired multiplicity of bags S, and then forward by one step in order to receive a subsequent desired multiplicity of bags S, always released in position Sa from the termination of the pneumatic retaining of the arms of the reels 5. The packs of bags Sa released and engaged with the pairs of needles 9 of the chain 7 hanging from the needles 9 as indicated with Sp and are transferred towards the right (observing figure 1) according to the arrow f7a, progressively assuming the hanging arrangements Sp. In the traditional structures of the apparatus of the present invention, all the set 8 with the returns 7R1 and 7R2 of the relative conveyor of the chain 7 (included the bearing structure) shall be continuously adjusted in transverse position, so as to follow the instantaneous irregularities of the position in which are the bags S which reach the position Sa and which are then released there as described above; this requires energy for displacement of significant masses with high inertia.

On the contrary, according to the present invention, the continuous adjustment of the set of the chain conveyor 7, 8 is not necessary, and only a continuous and limited displacement - translation and / or inclination - of the two needles 9 is performed, which are temporarily in the position 9a so as to assume a position aligned with the two holes F of the bag which is about to be released from the position Sa where it ceases to be held through suction by the arms of the reels 5. The needles 9 which are instantaneously in the position 9A can be moved through adequate servocontrols - with optical lights or other suitable devices - simply by exploiting the possibility of displacement of the needles 9 in position 9A, with movements - translation and / or inclination relative to the chain 7 - so as to guarantee a position thereof oriented below the holes F of the bag S which is about to be released from its position Sa due to the termination of the pneumatic retaining through the reels 5.

In order to obtain a translation - as indicated in figure 5 - or an inclination - as indicated in figure 6 - of the needles 9 in position 9A, in order to align them to the holes F of the bag which is instantaneously in Sa (due to the effect of transverse movements before achieving the position Sa), it is possible to provide the action of a tracer which acts according to the arrow f4 (figures 3 and

5) against the reaction of a spring 15. In this way it is possible to guarantee the instantaneously correct orientation of the needles in position 9A towards the holes F of the bag in Sa which is held by suction and is about to be released.

In view of the above description it is clear that only the instantaneous adjustments of the needles in position 9A below the bag S in releasing position Sa are required to guarantee a regular fall of the bags Sa in the pack being formed on the needles 9 which are in the position 9A with the chain stopped, until the accumulation of the desired pack of bags on the needles in position 9A, whilst the structure 8 does not require to be displaced (as occurs in the traditional solutions).

The packs Sp of bags S, formed as describe above, are subsequently transferred according to the arrow f7a from the chain 7, 9, towards a pick up station for taking the packs of bags.

In the pick - up station of the packs of bags, the collection can be anyway realized, also manually, as the frequency of arrival of the subsequent packs of bags which arrive transferred by the chain 7 is limited and each stop of the chain 7 is not too much protracted.

According to a possible and advantageous embodiment of the present invention, it is provided that the bags of more subsequent packs of bags are _ _

accumulated in corresponding engaging members which can be easily manipulated. Each of these engaging members is constituted simply by a U - shaped engaging member 21 , and in particular a U - shaped bar 21 susceptible to limited elastic deformations. This U - shaped engaging member 21 is susceptible (see also figures 11 and 12) to be received - inserted with a limited elastic return of the arms 21A - between opposite grooves 9B obtained in the two needles 9. These U - shaped engaging members 21 are useful also to handle the plurality of bags S as a whole, which are engaged to a same member 21. These U - shaped elastic member 21 can be advantageously prolonged so as to project beyond the needles 9A and so as they can be easily manipulated manually or also through automation, both for insertion between the needles 9 and for picking-up from said needles.

When the translation is ended of the U - shaped member 21 with the packs of bags Sp by means of the stroke according to the arrow f7a performed by the chain 7, a station can be provided for manual picking-up of the members 21 (and of the bags S engaged with them), or a specific station 30 can be provided for picking up the arriving bags Sp, as that illustrated in figures 1 and 2A.

In this station 30 moving means are provided for moving the U - shaped members both individually and with the packs of bags inserted, and in particular:

- a store 31 of said U - shaped members 21 ;

- a carrier 33 to receive and remove the packs of bags Sp which are transferred according to the arrow f7a of the chain 7 and which are put on said carrier 33; and

- a guide 35 for a carriage 37 provided with a lower gripper 39, suitable to be lowered and to engage the ends of the arms of the U - shaped members 21 (which arrive transferred to the chain 7) for the purposes described below.

Before the return 7A from the arrival branch according to the arrow f7a to the return branch according to the arrow f7b, the chain 7 places the needles 9 and the U - shaped members 21 below the carriage 37 and its gripper 39, in such conditions so that the gripper 39 can grip the ends of the U - shaped member 21, to which a pack of bags Sp is engaged, which have reached the position Spz (dashed line in figure 1). Therefore, this pack of bags can be _ _ picked up from the carriage 37, 39 and is transferred from this carriage 37 (rolling along the guide 35) till to put it on the carrier 33 as indicated in Spt (three intermediate positions of this transfer should be noted in Spn). At this point, the carriage 37 can return to the start point. According to a possible variant (see figure 2B) on the guide 135

(equivalent to the guide 35) in addition to a carriage 137 (equivalent to the carriage 37) also a second carriage 237 is provided; the carriage 37 picks up a U - shaped bar from the store 231 and present it in position U₀ to feed it to the chain 7 which transfers it according to the arrow f7b; the carriage 137 is suitable to transfer a U - shaped bar with the pack of bags Spm from the position U₀ till to deposit the pack of bags Spn in the position Spt on the carrier 33 and farther. The movements of the two carriages 237 and 137 are suitably synchronized for the respective operations to be performed.

In any case, it is advantageously provided that the U - shaped members are automatically inserted in their seats on the chain 7 as those previously used for the formation and the picking-up of the pack of bags are unloaded.

In view of the above description, it is clearly apparent that the U - shaped engaging members are transferring members for transferring the packs of bags.

Another preferred embodiment of the presents invention provides that the engaging and transferring members are formed by sleeves 321 (i.e. tubular bodies), which are arranged on the needles 9 (so that they are inserted on them), one for each needle 9, before arranging the bags. At an end of the sleeves 321 , the end for the insertion of the needles, abutment members are provided, projecting laterally, such as for example a flange 340. The bags are thus stacked in such a way that the sleeves 321 are inserted in the holes of the bags. The first stacked bag abuts on the lower flanges 340 of the pair of sleeves 321.

In practice, the pack of bags Sp is supported by the flanges 340 of the sleeves arranged on the two corresponding needles, and it is therefore possible to handle the pack by acting on the two sleeves.

The need of having sleeves instead of the U - shaped members derives from the fact that in some embodiments of the apparatus according to the present invention the center to center between the needles 9 can be adjusted (as shown in figure 15) by means of adequate means (such as for example _ _

predefined fixing or relative slip positions of the needles on a support) for the adaptation to types of bags with different center - to - center between the holes. A U - shaped engaging member of given dimensions according to the present invention does not allow to vary its lateral dimension to be adapted to center - to - center of needles of different type, unless a complex structure thereof. An alternative is the arrangement of U - shaped members of different lateral dimensions. This problem is solved by using sleeves, which do not present constraints in lateral direction.

To prevent a pack Sp from separating, or to be more precise, to prevent the extraction of the bags from the sleeves 321 at correspondence of their head (the end opposite to the flange 340), the sleeves 321 present at the top anti - removal means, such as in this example for each sleeve 321 a cap 341 which can be snap coupled on a nip defined on the outer diameter of the head of the sleeve and provided with a portion 341A laterally projecting relative to the outer diameter of the sleeve; this portion 341A prevents the bags from slipping out from the head of the sleeves. A variant of this cap (not shown in the figures) provides that the snap coupling occurs through coupling of the stem of the cap with the inner diameter of the head portion of the sleeve.

Analogously to the U - shaped engaging members, a pick - up station 330 is provided for the packs of bags Sp, arranged at the end of the translation stroke of the needles with sleeves and corresponding packs.

In this station 330 a store 331 for sleeves 321 is provided (see figures 15 and 16), and moving means of pairs of sleeves, both singularly and with packs of bags inserted on the sleeves, which comprise an actuator of vertical translation 342 for a gripping group 343 of the sleeves 321. This actuator is arranged on a carriage 337 sliding along a guide 335 transverse to the chain 7.

The gripping group 343 provides two grippers 339, whose distance can be adjusted. For example, these grippers 339 are arranged on a horizontal bar

343A at correspondence of preset positions belonging to a preset series of fixing positions 343B defined on the same bar. The pair of grippers 339 can be replaced also with an individual gripper of suitable width, which acts contemporaneously on both the sleeves.

See figure 16. The gripping group 343 can move for example towards the store / warehouse 331 of sleeves 321. The grippers are lowered until the _ _

warehouse so as to pick up two sleeves. Then they are lifted and the group is translated above the pick up station of the packs of bags on the chain 7. The grippers are then lowered until they take the end heads of the sleeves 321 with the packs inserted. The grippers are lifted, bringing with them the sleeves and the corresponding pack Sp (see figure 17), which is moved towards a carrier (not shown in the figures), where it is arranged and transferred towards another storage / working area.

It should be noted that the sleeves can be also used in apparatuses in which the distances of the needles in respective pairs can not be adjusted. Furthermore, it should be noted that the particular embodiments of the engaging members (U - shaped members and sleeves) can be used also with apparatuses of the traditional type, where the adjustment of the position of the needles in the area Sa of receiving the bags occur by moving all the set of the chain conveyor 7, 8. It is understood that what is illustrated purely represents possible non- limiting embodiments of the invention, which may vary in forms and arrangements without departing from the scope of the concept on which the invention is based. Any reference numbers in the appended claims are provided for the sole purpose of facilitating the reading thereof in the light of the description hereinbefore and the accompanying drawings and do not in any way limit the scope of protection of the present invention.

Claims

_ _CLAIMS

1. An apparatus for forming packs of plastic bags (S) or the like presenting holes - in particular two holes (F) - along one edge, said apparatus comprising a multiple reel which presents the bags singularly to a transferring chain (7, 9) for transferring the packs of bags (Sp) accumulated in needles (9) - individual or in particular pairs of needles - present in succession on said chain, characterized in that on said chain (7) the individual needles (9) are mounted in such a way as to be varied in position (9A), so as to guarantee the picking-up of the bags which they must perform for transferring also in case of lateral movement of the bag.

2. An apparatus as claimed in claim 1 , characterized in that said needles (9) are constrained to the chain (7) so as to be translated relative to it.

3. An apparatus as claimed in claim 1 and / or 2, characterized in that said needles (9) are constrained to the chain (7) so as to be inclined angularly relative to it.

4. An apparatus as claimed in one or more of the previous claims, characterized in that it comprises adjusting means for adjusting the center - to - center distance between the needles (9) of a same pair.

5. An apparatus as claimed in one or more of the previous claims, characterized in that said chain (7) presents in succession seats for housing U - shaped transferring members (21) suitable to engage the bags fed to form individual packs (Sp) of bags, said U - shaped members facilitating the subsequent handling of said packs, each of said seat being formed by a pair of parallel and mutually spaced needles (9).

6. An apparatus as claimed in claim 5, characterized in that said seat are channel developed (9B), between which the U - shaped engaging / transferring members (21) are held with a limited elastic deformation.

7. An apparatus as claimed in one or more of the previous claims, characterized in that it comprises, downstream of said transferring chain (7), a picking up device (30, 39) of said U - shaped transferring members and said packs of bags engaged in them.

8. An apparatus as claimed in claim 7, characterized in that said picking up device (30, 39) performs an active stroke for transferring the packs of bags (Spz) from said chain (7) to a removing system (33), and a return stroke

. .

to prepare the same to load the U - shaped members (21) taken from a storing system (31).

9. An apparatus as claimed in one or more of the previous claims, characterized in that it comprises adjusting means for adjusting the center - to - center distance between the needles (9) of a same pair.

10. An apparatus as claimed in one or more of claims 1 to 4, characterized in that it comprises engaging / transferring members suitable to engage the bags fed to form individual packs (Sp) of bags, said engaging / transferring members facilitating the subsequent manipulation of said packs, said engaging / transferring members comprising at least one sleeve (321) to be arranged around one said needle (9), to said sleeve corresponding a hole of a bag to be engaged.

11. An apparatus as claimed in claim 10, characterized in that to one end of said at least one sleeve (321), corresponding to the section of insertion of the needle (9), abutment means (340) are present, laterally projecting, on which a first stacked bag rests.

12. An apparatus as claimed in claim 11 , characterized in that said abutment means are constituted by a flange (340).

13. An apparatus as claimed in claim 11 or 12, characterized in that it comprises anti - extracting means (341) present at correspondence of the end head of the sleeve (321) opposite to said abutment means (340).

14. An apparatus as claimed in claim 13, characterized in that said anti - extracting means (341) comprise a cap (341) snap coupleable on the head of the sleeve (321) and provided with a portion (341A) projecting laterally relative to the outer diameter of the sleeve.

15. An apparatus as claimed in one or more of claims 10 to 15, characterized in that it comprises moving means (335, 337, 342, 343) for handling said at least one sleeve (321), both singularly and with a pack of bags inserted on it.

16. An apparatus as claimed in claim 15, characterized in that said moving means (335, 337, 342, 343) comprise and actuator of vertical translation (342) for a gripping group (343) of said at least one sleeve (321), said actuator being arranged on a carriage (337) sliding along a guide (335) transverse to the chain (7). _ _

17. An apparatus as claimed in claim 16, characterized in that said gripping group (343) comprises at least one pair of grippers (339) whose distance can be adjusted, or an individual gripper of adequate width suitable to act on one or more sleeves contemporaneously.

18. An apparatus as claimed in claim 16 or 17, characterized in that said gripping group (343) is movable between a store / warehouse (331) of sleeves (321) and an area for unloading packs of bags, passing through the area for picking-up of the packs on said chain (7).

19. An apparatus as claimed in one or more of claims 10 to 18, characterized in that said engaging / transferring members comprise a pair of said sleeves (321) arranged on a corresponding pair of needles (9).