GB2244983A

GB2244983A - Changing web rolls

Info

Publication number: GB2244983A
Application number: GB9111525A
Authority: GB
Inventors: Antonio Gamberini; Roberto Osti; Alver Tacchi; Alessandro Venturoli
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1990-06-12
Filing date: 1991-05-29
Publication date: 1991-12-18
Anticipated expiration: 2011-05-29
Also published as: BR9102396A; DE4119290A1; GB2244983B; GB9111525D0; JPH04239428A

Abstract

A device (1) for changing rolls of material (2), typically in an unwinder of a wrapping machine (3), comprises a head (16) by which the rolls (2) are taken up singly from a magazine (5) and transferred to an uncoiling station. The head (16) carries three arms (19) radiating from its own axis, which are reciprocated so as to spread or contract by a cam and drive (21...24) incorporated into the head itself. Freely revolving rollers (27) are mounted one to the end of each arm (19) to grip the periphery of a web roll, their axes being substantially parallel with that of the head. In effecting the transfer movement, the head (16) is traversed both parallel with and transversely to its own axis by respective actuators (31, 15). The head may incorporate a device for removing empty cores from the uncoiling station. <IMAGE>

Description

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A device for changing rolls in a machine utilizing strip material The present invention relates to a device by means of which to change rolls of strip material, in a machine utilizing such material. Such a machine, generally considered, would be a power machine designed to operate using continuous strip material, and more particularly a wrapping machine by which material of the type in question is used to envelop or package commodities. The art field of wrapping machines, for example as reflected in US 4,441,662, teaches the embodiment of a device for supplying and changing rolls of strip material that comprises a magazine, by which a plurality of rolls can be supported side by side and fed in succession toward a transfer position; fTom this positions the rolls are taken up singly by corresponding transfer means and supplied to an uncoiling platform. The transfer means consist in an arm, provided with a cylindrical element or shank axially and slidably insertable into the core or centre hole of the roll

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positioned forwardmost in the magazine and capable of movement, generated by an actuator, betwem a first position, in which the cylindrical shank is disposed coaxially with the magazine axis, and a second position in which the shank is coaxial with an element carried by the uncoiling platform and serving to support the roll. Devices of the type outlined above are beset by certain drawbacks deriving from the difficulties that can arise when the shank is inserted into the core of the roll. In effect, the core of the roll may happen to be deformed, or to be out of axial alignment with the magazine as a result of the roll itself being less than perfectly cylindrical or of incorrect proportions. The object of the present invention is to provide a device that will pick up rolls of strip material from a magazine and transfer them to a position of utilization without the drawbacks encountered in prior art embodiments, that is, a device able to effect a secure grip on the rolls irrespective of their shape and size. The stated object is realized, according to the present invention, with a device for changing rolls of strip material in a machine making use of such i i material, comprising a head equipped with gripping means by which the rolls are engaged singly and in succession and serving to take up the rolls from a magazine and transfer them to an uncoiling station afforded by the machine, and characterized in that such gripping means comprise a plurality of arms supstantially radiating from an axis of the head, freely revolving roller means mounted to the arms with axes parallel to the axis of the head and designed to engage the outermost surface of the single roll, and drive means by which the arms are reciprocated along their own axes; and in that the head can be traversed in a direction parallel with its own axis by first actuator means; and traversed in a direction transverse to its own axis by second actuator means. in a preferred version of the device thus embodied, the transfer head further incorporates a device by which the empty core of each fully depleted roll of material is removed automatically from the relative station of the machines advantageously comprising bolt means designed to impinge on the outer surface of the corey which are carried by each arm of the gripping means and reciprocated together with the arm by the drive means.

2 cl The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which: -fig 1 schematically illustrates a first embodiment of the device according to the invention, viewed in frontal elevation; -fig 2 is the enlarged view of a detail of fig 1; -fig 3 is a side elevation of the detail of fig 2; -fig 4 illustrates a preferred second embodiment of the device according to the present invention in a view similar to that of fig 3; -fig 5 is a frontal elevation of the detail shown in fig 4; -fig 6 shows the detail of figs 4 and 5 enlarged and in perspective. With reference to fig 1 of the drawings, 1 denotes a device, in its entirety, for changing rolls 2 of strip material utilized by a production machine 3 of which the device itself forms an integral part. The device I is mounted to the fixed frame 4 of the machine 3, and comprises a magazine 5 designed to accommodate a plurality of change rolls 2 (one roll only is visible in fig 1) stacked face to face and substantially in contact one with the next, which are fed in succession toward a transfer station 6.

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The rolls 2 are fed toward the transfer station 6 by means of a device 8 (not illustrated in detail) of the type, for example, as disclosed in Italian patent application n 3461 A190. 9 denotes a transfer device comprising an arm 9' rigidly associated at one end (the end uppermost, as viewed in fig 1) with a pivot 10 of which the axis is disposed substantially parallel to the axes of the rolls 2; the pivot 10 is hung slidably and rotatably from a bracket 11 rigidly associated with the frame 4 (see also fig 3). The pivot 10 exhibits a splined portion 12 to which one end of a crank 13 (the lower end, as viewed in fig 3) is slidably mounted; the remaining and of the crank 13 is attached to the rod of a linear actuator 15 mounted to the frame 4. 16 denotes a head rigidly associated with the end of the arm 9' remote from the pivot 10, comprising an essentially cylindrical hollow boss 17, by means of which the rolls 2 are taken up and transferred. The head 16 also comprises three radial sleeves 18 issuing from the cylindrical outer surface of the hollow boss 17, disposed substantially within a common plane distance one and spaced apart at identical angular from the next, each accommodating a respective coaxially disposed and slidable arm 19 of which one end is directed through the relative hole 20 afforded by the hollow boss 17 and the sleeve 18 and into the bore of the hollow boss 17. The arms 11 thus constitute a part of the head 16. The ends of thh arms 19 located within the hollow boss 17 carry respective cam follower rollers 21, freely revolving and disposed with axes parallel to the axis of the hollow boss 17, which engage in relative grooves 22 afforded by a circular plate 23 mounted coaxially and rotatably in the bore of the boss 17 and constituting cam means. 24 denotes a linear actuator mounted to the arm 9% of which the rDd 25 is made fast to the plate 23 at a point offset in such a way as enables the plate to be rotated in either direction. As will become apparent in due coursen the cam followers 21. the grooves 22, the cam plate 23 and the actuator 24 together constitute drive means by which to reciprocate the arms 19 in relation to the sleeves 18. The ends of the arms 19 remote from the boss 17 afford support by way of corresponding pivots 26, disposed with axes parallel to the axes of the rolls 2, to respective freely revolving rollers 27 ..7 projecting toward the magazine 5; in a preferred embodiment, the rollers 27 will be faced with a. resilient material (not illustrated). The right hand end of the pivot 10, as viewed in fig 3v affords an annular seating 29 serving to accommodate tie bottom end of a link member 29 of which the top end is fastened to a rod 30 disposed parallel to the pivot 10, forming part of a linear actuator 31 associated rigidly with the fraM2 4 and serving to invest the pivot 10 with reciprocating motion along its own axis. 32 denotes a further pivot disposed parallel to the pivot 10 of the transfer device5 which is spaced apart from the latter by a distance equal to that which separates the pivot 10 from the axis of the head 16, and mounted to the frame 4 at a station 33 corresponding to the position in which the rolls 2 are utilized, i.e. uncoiled, by the machine 3. In operation, as a roll 2 is progressively unwound and consumed by the machine 3, the arm 9' will be poOtioned in such a way that the three rollers 27 register in contact with the peripheral surface of the roll 2 occupying the transfer station 6. As the roll at the uncoiling station 33 nears total depletion, the pivot 10 will be shifted axially by the relative actuator 31, such that the roll 2 currently in the grip of the head 16 is separated from the body of rolls loaded in the magazine 5. The linear actuator 15 first mentioned now operates to rotate the arm 9' about the axis of the pivot 10 in such a way that the new roll 2 is brought into a position coaxial with the uncoiling pivot 32, from which the empty core 34 of the previous roll 2 will have been removed either manually or by means of an automatic device 35 to be described in due course 6. traversed axially by the relative actuator 13 in the direction opposite to that of the previous movement, to slip the new roll 2 over the uncoiling pivot 32. This accomplished;'the cam plate 23 is caused to rotate anticlockwise (as viewed in figs 1 and 2) by the corresponding linear actuator 24 such that the arms 19 recede from the hollow boss 17, distancing the rollers 27 from the surface of the roll 2, whereupon the arm 9' is returned to the transfer station 6 by the relative actuators 31 and 15. The rolls 2 contained in the magazine 5 are indexed bodily through one step by the feed means 8 to bring a new roll 2 into the transfer station 6.

with reference to figs 45 5 and At this point, the pivot 10 is Finally, the pivot 10 is moved toward the transfer station by the relative actuator 31, in such 1 way as to offer the head 16 to the new roll 2 and Cus position the rollers 27 over the outer cyindrical surface of the roll 2, whereupon the cam plate 23 is rotated by the relative actuator 24 to bring the rollers 27 into contact with the roll 2 and return the device 1 to the start of cycle configuration. It will be seen from the foregoing that the freely revolving rollers 27 constitute gripping means such as permit of laying a secure hold on each roll 2, independently of any defect in shape or size of the single Tails themselves. Similar!y5 it will be noted that the gripping means in question are able to adhere faultlessly to the peripheral surface of the roll 2, given the ability of the call 2 to rQtate marginally about its own axis; moreover such rotation is enabled precisely by the adoption of the freely revolving rollers 27 at the ends of the arms 19. Neidless to say, the number of radial arms 19 and corresponding rollers 27 described and illustrated reflects just one possible example of the device's embodiment; the effective number in practice could be different.

1::! The embDdiment of the invention shown in figs 4 to 6 relates likewise to a transfer device 36, which differs from the device 9 described above insofar as it comprises a device 35 for removing empty roll cores 34 automatically. To this end, the sleeves 18 of the first device 9 are replaced in the second device 36 by respective frames 37 of substantially rectangular shape, each comprising an inner wall 38 rigidly associated with the outer periphery of the hollow boss 17, two side walls 39 extending outward from opposite side edges of the inner well 33, substantially in a radial direction with respect to the hollow bass 17, and an outer wall 40 parallel to the inner wall 38, of which the face outermost affords an appendage 41 extending parallel to the respective roller 27 and terminating at the end farthest from the frame in a flat surface 42 lying Oerpendicular to the axis of the roller 27. Each frame is embodied with through holes 43 and 44 afforded respectively by the inner wall 38 on the one hand and the outer wall 40 and the appendage 41 on the other, coaxially disposed one with another and slidably accommodating the respective arm 19. As discernible more clearly from figs 5 and 6, the two side walls 39 of the frame 37 combine to create 1 1.

io a slot 45, radially disposed in relation to the hollow boss 17 and encompassed by the inner wall 38 on the one hand and the outer wall 40 on the other. The slot 45 is engaged transversely and slidably by guide means comprising a cylindrical housing 46, which affords a radially disposed through hole 47 located between and coaxial with the holes 43 and 44 of the frame and occupied by the arm 19; more exactly, the housing 46 is rigidly associated with the arm 19 and thus able to move along the slot 45 in a direction perpendicular to its own axis. The housing 46 is mounted to the relative arm with its axis disposEd parallel to the corresponding roller 27; aof affords a throqgh axial hole 43 of rectangular section freely engaged by slide mean=, comprising a rectangular section rod 49 of which a fi7st end, positioned on the side of the arm 1? occupied by the roller 27, emerges and extends from the housing 46 to support a tubular guide disposed parallel with the arm 1?. Each tubular guide 50 proVides the support for a relative spring-loaded bolt 51 disposed radially in relation to the hollow boss 17, the resulting plurality of bolts 51 thus constituting gripping means that are a feature of the operation of the removal device 35.

Each bolt 51 comprises a shaft 52, fitted with a point 53 at the end nearest to the boss, which is carried slidably by the guide 50 and loaded against a spring 54 lodged between the point 53 and the radially innermost end of the tubular guide 50, in such a manne---!- as to cause a stop ring 55 associated with the remai-ning end of the shaft 50- to register with the radially outermost end of the guide 50.

As discernible from figs 4 and 6, the end of the rectangular sect-Lon rod 49 remote from the end associated with the tubular Quide 50 affords an axiall slot 56 accom-modati-ng a spring 57, which is compressed between th2 end of' the slot 56 nearest the bolt 51, on the one hand, and a pin 5a inserted transverS21Y through the housing 46 on the other.

Thus, the rod 49 is able to slide axially within the housinQ 46, te-nsio-ned tj-v the spring 57!, between a retracted at-rest position (bold line in fig 4), in which the end surfaces 42 of the appendages 41 and the lateral surface of each tubular guide 50 are in flush contact with one lateral surface of I -ween the rollers 27, and an he roll 2 gripped bet extended operating position (phantom line in fig 4) wher2by, in the absence of a roll 2 of material from the space encompassed by the rollers R7, the p points 53 are placed to impinge radially on an empty core 34. In operation, the removal of an empty core 34 from the uncoiling pivot 32 is accomplished by spreading the arms 19a moving the head 16 toward the pivot 32 until the uncoiling position 33 is reached, then drawing the arms 19 radially inward. Thus, with the roll 2 currently occupying the uncoiling pivot 32 51 can move into their and be made to engage arms 19.

16 can be distanced from the and with it the empty core 34 leaving the pivot 32 free to accept a new roll 2 loaded in the manner already described.

totally depleted, the bolts extended operating positiOT the core 34 by radial Thereafter, the head uncoiling station 335 of the deolated roll, contraction of the 0 i h:

Claims

Claims

1 P. device for changing rolls of strip material in a machine designed to make use of such material, comprising a head equipped with gripping means by which the rolls are engaged individually and in succession and serving to take up the single rolls from a magazine and transfer them to a station afforded by the machine at which the strip material is uncoiled characterized -in that gripping means comprise a plurality of arms substantially radiating from an axis of the head, freely revolving roller means mounted to the irms with axes parallel to the axis of the head and designed to engage the outermost surface of the single roll, and drive means by which the arms are reciprocated along their own axes; and -in that the head can be traversed in a direction parallel with its own axis by first actuator means, and traversed in a direction transverse to its own axis by second actuator means.

0 1 1-,'S 2) 3) A device as in claim 1, wherein the arms of the gripping means are spaced apart at identical angular distance one from another.

A device as in claim 1 or claim 2, wherein drive means comprise cam means, and cam follower means associated with a respective part of each arm and in engagement with the cam means.

A device as in preceding claims, wherein the head further comprises a device serving to remove the core of a fully depleted roll of material from the uncoiling station of the machine.

A device as in claim 4, wherein the core removal device comprises bolt means designed to impinge or, the outer surface of the cores which are carried by Mch arm of the gripping means and reciprocated together with the arm by the drive means.

A jevice as in claim 5, further comprising guide means mounted to each arm and disposed parallel to the axis of the head, slide means associated with and capable of movement in relation to the guide means in a direction parallel to the axis of the 4 1 1 " head, and spring means located between the guide means and the relative slide means, wherein the bolt means are coupled to and capable of movement together with the slide means5 parallel to the axis of the head and through the agency of the spring meansy between a retracted at-rest position and an extended operating position.

7) 9) A device as in claim 6, wherein the bolt means carried by each arm of the gripping means comprise a shaft disposed parallel to the arm, slidably associated with the corresponding slide means and capable thus of movement ip Telation to the slide means toward the axis of the head through the agency of further spring means.

A device for changing rolls of strip material in a machine making use of such materialn substantially as described with reference to the accompanying drawings.

Published 1991 at The Patent Office. Concept House, Cardiff Road. Newport. Gwent NP9 I RH. Further copies may be obtained from Sales Branch. Unit 6. Nine Mile Point. CWmfelinfach, Cross Keys. Newport. NP I 7HZ. Printed by Multiplex techniques ltd. St Mary Cray. Kent.