GB2178011A - Traverse motion apparatus for a web of material to be rolled up - Google Patents

Abstract

A traverse motion apparatus for a web of material which is to be rolled up comprises a hollow guide roller (W) (Figure 2) for the web, which roller is mounted at its centre (M) on a fixed support (T) to be freely rotatable thereon and capable of being deflected in all directions. A bearing for the roller (W) is arranged at one end of the roller to be capable of eccentric adjustments relative to the support (T). Reduction gearing (G) in the roller imparts equally to the two ends of the roller a slow precession motion corresponding to the adjusted eccentricity. The position of the centre (M) of the roller remains unchanged. Tensions in the web of material remain slight and are evenly distributed. <IMAGE>

Description

SPECIFICATION Traverse motion apparatus for a web of material to be rolled up This invention relates to a traverse motion apparatus for a web of material which isto be rolled up, the apparatus comprising a rotatable guide rollerforthe web and means for continuously changing the position ofthe roller axis in operation.

Traverse motion apparatus is used to prevent a roll of material bunching up at the edges. Guide rollers subjected to a traverse motion oftheir axis have been usedforsuch apparatus. Thus,forexample, German Patent No. 2253037 discloses a traverse motion apparatus in which a rotatable roller is pivotally mounted at both ends. One end is held in position in its bearing whilethe other is eccentrically arranged so that it executes precession motion. The roller is set into rotation by the web of material moving over it and planet gearing accommodated inside the roller imposes the precession motion on an eccentric pivot pin adjustably mounted in an eccentric end face ofthe roller.The magnitude ofthe precession motion can be adjusted by infinitely variable adjustment ofthe eccentric pivot pin. The precessional speed of rota tion and hencethefrequencyofthetraversemotion can be varied by appropriate choice of the transmission ratio in the planet gearing.

Atraverse motion roller of this kind, however, entails disadvantage in operation since traverse motion produces tensions in the longitudinal direction. Since the traversing movement acts at only one of the two ends ofthe roller, these longitudinal tensions in the material are uneven.

U.S. Patent No. 2,485,705 discloses a traverse motion apparatus in which a guide roller has its axial shaft rotatably mounted in a frame. The frame can rock to a limited extent in one plane about a rocker shaftarranged perpendicularlytotheaxisoftheroller. The rocker shaft is so arranged that an extension of its axis passes through the centre ofthe rollerand the two ends ofthe roller are therefore moved in opposite directions in operation. In this apparatus, the frequency of deflection oftherolleraxis is again derived from the speed of rotation ofthe roller byway oftransmission means.Although longitudinal ten sions inthefabric are in this case slightly reduced, the quality of winding ofthe web of material is inferior since the roller axis only executes a simple rocking movement instead ofthe usual movement of precession.

It is an object of the present invention to reduce the disadvantages of known traverse motion apparatus and to provide an apparatus with which it is possible to achieve an improved quality of winding by the precession motion of the roller axis as well as only slight longitudinal tensions in the material.

According to this invention there is provided traverse motion apparatus for a web of material which is to be rolled up, the apparatus comprising a rotatable guide rollerfortheweb and meansforcon- tinuouslychanging the position ofthern'leraxisin operation wherein a) the roller is mounted substantially at its centre on a support on which it is rotatable, and can be deflected in all directions; and b) reduction gearing driven bythe roller is disposed withinthe roller, the driven output of which gearing is connected to a bearing which is arranged on the support and which is radially adjustable in an end part ofthe roller.

Good qualityofwinding is obtained in that the axial shaft of the roller can execute a true precession motion, and the tensions produced in the web of material can be uniform since the precession motion passes substantially through the centre of the roller, so that distortion is largely absent at the edges ofthe fabric.

The present apparatus has the advantage of enabling even webs of lightweight fabric to be subjected to a traverse motion without damage.

An embodiment ofthe invention will now be described by way of example, with reference to the drawings in which: Figure lisa general view of a roller shown in accordance with the invention; Figure2 is a diagrammatic and simplified illustration of the construction ofthe roller of Figure 1; Figure 3 is a diagrammatic and simplified illustration of an end part ofthe roller; Figure4 is a diagrammatic and simplified illustra- tion of a coupling part at the centre of the roller; Figure 5a is an enlarged longitudinal section through the centre of the roller; Figure5b is a longitudinal section through an end part ofthe roller; and Figure 6is an axial view of an end part.

Referring to the drawings, Figure 1 illustrates the principle of the arrangement.

Aguide rollerW ofatraverse motion apparatus isa hollow roller mounted on afixed supportTsothatthe rollerW can be deflected in all directions about its centre M. The position ofthe geometrical axis X ofthe rollerW can therefore constantly be changed relative tothesupportT, and can be moved, for exampleto a newposition XE Sincethe rollerWis mounted to be deflected in all directions abouts its centre M it can execute a tumbling or precession motion about its centre M. The rollerWhas an adjustmentdeviceVat one end face for adjusting the eccentricityforthe desired precession motion at that end.The fixed sup- portTmay extend through thewhole length ofthe hollowrollerWand be clamped or mounted at both its ends, i.e. at both ends ofthe roller. Figure 1 shows a variation in which the support T is fixed only at one end Lwhile the mounting forthe centre M of the guide rollerWisarranged atthefreeendofthesupport.

Since the rollerWcan be deflected in all directions at its centre M, movements of precession exactly symmetrical about the centre are obtainable at both ends ofthe roller, so that a good quality of winding can be obtained atthe edges ofthe web. Longitudinal tensions in thefabricare generally uniformlydistributed and are only slight, so that no lateral pull is produced at the edges of the fabric.

The construction oftheapparatuswill now be described with reference to Figure 2. The fixed supportT is indicated by double lines in the region ofthe centre M ofthe roller and also at its two ends where it is clamped or mounted in bearings L outside the roller W; the supports is otherwise indicated by single lines. This support T does not rotate but is stationary.

A bearing capable of being deflected in all directions, e.g. atumbler bearing 1 (see also Figure 5a) is mounted on the supportTatthe centre M. The bearing 1 is carried in a supporting disc2 arranged inthe interior ofthe rollerW. A possible displacement ofthe geometrical axis X ofthe roller, and thus deflection of the rollerWto another position, are indicated by dash-dot lines X' and W'. Reduction gearing G is provided near the centre of the roller, two the right of the disc 2. The precessional speed of rotation forthe traverse motion is derived from the rotation of the rollerW by way of the reduction gearing G.That gearing is in this embodiment a planet gearing having a sun wheel 6fixed on the supportT,a second sun wheel 7 coaxial with the first but rotatably mounted on the support by a bearing 18, and a supporting part 4fora planetwheel 5,which part5isalsorotatably mounted onthe support T. The hollowshaft8 is mountedbytwobearingsll and l8onthesupportT.

Figures 2 and 5a showthatthe left end ofthe hollow rollerW is open so that it can execute its precession motion about the support T. The right end of the roller is closed byan end part 9. The shell ofthe rollerWis mounted on a bearing 10 for rotation on the end part 9. The shell can therefore rotate independently ofthe end part 9. As will be explained, a rotation entrainment means establishes connection between the hol lowshaft8 andtheend part9sothatthe hollow shaft and end partcan be driven atthesamespeed of rotation from the output ofthe reduction gearing G.

The pivot bearing 11 of shaft 8, which bearing is situated at the end ofthe roller, is mounted in a carriage 13 (see Figure 3) which is radially displace- able in a guide track 9a ofthe end part9. The midposition ofthe carriage 13 is shown in solid lines in Figure 3. One end position of displacement is shown in broken lines and indicated by the reference 13'. The distance between these two positions is the maximum obtainable eccentricityforthe precession motion. The eccentricity may be adjusted to a desired value between the two extremes by means of an adjustment device V.

The adjustment device V is only roughly indicated in Figure 2. It comprises a handwheel 19 (Figure 5b) surrounding the solid supportTforcarrying outthe adjustment. This wheel 19 acts on the carriage 13 by means of level gears 14 and an adjustment spindle 12 to displace the carriage radially. Such a device is known for example, from U.S. Patent No. 1,516,993.

The coupling between the rollerW and the reduction gearing G which is merely indicated in Figure 2 is shown in Figure 4. The supporting disc2 in the roller W rotates together with the roller at a speed of rotation determined by the speed of the web of material moving over roller. In addition, the supporting part4 is freely rotatable on the fixed supportT, as mentioned. The supporting disc 2 and supporting part4 are parallel and side by side. Radial incisions or recesses in the form of a cross are arranged on their surfaces facing each other and resilient strips (see aiso Figure 5a) are inserted in these incisions or recesses to serve as coupling elements. One such strip 3 is shown in section to the right in Figure 4.The strip 3 engages by its bent, outer portion with a cut-out in the supporting disc 2 while its inner part fists into corresponding cut-outs in the supporting part 4. In Figure 2 the cut-outs are shown as unshaded areas 2' and 4to mark them out from the remaining parts which are shown hatched and in section. The resilience ofthe strips 3 can compensate for minor movements of displacing andtilting between the supporting disc2 and supporting part 4 in operation since the rolierW is thus able to take up a different axial position with respect to the fixed supportTwhereasthe reduction gearing G remains coaxial with the supportT.

Construction ofthe apparatus is shown in more detail in Figures 5a and 5b. Figure 5a shows the part of the apparatus at the centre ofthe rollerwhile Figure 5b showsthe end part of the rollerwith the end face.

The fixed support T is held at both ends by the bear ingsL.Thetumblerbearing 1 is mounted on this supportTatthe centre of the roller, Figure 5a, and the supporting disc 2 extending in the interior of the roller shell is mounted to be rotated and deflected on this bearing. This disc 2 can be fixed to the internal surface ofthe rollershell,forexample by means ofafrustoconical clamping member 16 which can be screwed into position. Adjacentthe disc 2, the supporting part 4 is mounted on a bearing 17to be rotatable aboutthe fixed support T. The elastic coupling strips 3 are indicated by a line.The strips 3 are placed with their narrow edges against the flanks of the recesses in the supporting disc 2 and in the supporting part4.The part4servesascarrierfortheplanetwheel Swhich is mounted bya pin 16. In addition,thefirstsunwheel 6 is non-rotatably mounted on the fixed supportTand the rotatable sun wheel 7 is arranged coaxially to the sun wheel 6. The fixed sun wheel 6 is preferably mounted on a sleeve 6' which is non-rotatably fixed to the supportT, e.g. by being clamped in position. The sleeve6'formsa bearing sleeve and carries all the rotation bearings in the region of the centre ofthe roller, such as the tumbler bearing 1 and the bearings 17 and 18 forthe supporting part 4 and forthe rotatable sun wheel 7.As mentioned, the rollerW is set in rotation by the web of material moving over it. This rotation is transmitted from the supporting disc 2 two the supporting part 4 bythe coupling 3. The supporting part 4 with its planet wheel 5 thus constitutes the drive inputtothe planet gearing while the drive out- put is formed by the sun wheel 7 which is rotatable on a bearing 18. The output sun wheel 7 is non-rotatably attachedtotheend part9bythe hollowshaft8.

The planet wheel S engages simultaneously with both sun wheels 6 and 7. Theyhavethe same dia meter but a slightly different number of teeth, e.g. 40 and 41 teeth, respectively. The speed of rotation of the output of the planet gearing and of the hollow shaft 8 is thus considerably reduced compared with that of the roller W. This reduced speed of rotation of the shaft 8 serves as the speed of rotation forthe precession motion ofthe roller.

The end part of the rollerWisshown in longitudinal section in Figure 5b and in axial view in Figure 6. The fixed supportT and its bearing L are again shown. The end ofthe hollow shaft 8 is rotatably mounted in a bearing 11 on the fixed support T. The hollow shaft8 is adjacent and firmly connected to a block which extends into the sliding carriage 13. The carriage 13 is radially displaceable in guide tracks 9a ofthe end part 9. This displacement continuously shiftsthegeomet- rical axisofthe rollerWin relationtothefixedsupport Tto adjustthe necessary eccentricity forthe precession motion ofthe roller.The carriage 13 and also, through the guides 9a, the end part9 are thus carried along bythe hollow shaft 8 and set into slow rotation at the rotational speed of precession.

The carriage 13 carries the pivot bearing forthe rotation of the end part 9 relative to the fixed support T, as mentioned. The end part 9 contains the adjustment device Vfor adjusting the eccentricity eforthe precession motion. The construction of the adjustment device V is based on that of known devices and contains a sleeve 20 rotatably inserted in the carriage 13. The sleeve 20 engages, by means ofthe bevel gearing 14, with the hand-operated adjustment wheel 19 which is rotatably mounted on part of the carriage 13. The sleeve 20 is internally threaded to engage with the adjustment spindle 12. The latter is mounted on a pin 22 in the end part 9to be capable of deflection but not rotation. When the handwheel 10 isturned, the sleeve 20 on the spindle 12 aiso rotates and is displaced on the spindle and moves the carriage 13 with the pivot bearing 11 radially away from the centre of the end part 9. The geometrical roller axis Xis thus deflected from the axis of the support T. The bearing 10 is inserted between the end part 9 and the rollershell sothatthe rollerWcan be rotated bythe transported web of material independently of the slow rotation of the end part 9.

Since the adjustment spindle 12 is capable of deflection on the pin 22, the small tilting movements and longitudinal displacements between the end part 9with the carriage 13 andthefixed supportTcan easily be absorbed.

Claims (13)

1. Traverse motion apparatus for a web of material which is to be rolled up, the apparatus comprising a rotatable guide rollerfortheweb and means for continuously changing the opposition ofthe roller axis in operation,wherein: a) the roller is mounted substantially at its centre on a support on which it is rotatable, and can be deflected in all directions; and b) a reduction gearing driven by the roller is disposed within the roller, the driven output of which gearing is connected to a bearing which is arranged on the support and which is radially adjustable in an end part of the roller.

2. Apparatus according to claim 1, wherein the reduction gearing is a planet gearing having first sun wheel rotationally fixed on the support and a second sun wheel which is mounted coaxiaily with the first, is rotatable on the support, and constitutes the driven output.

3. Apparatus according to claim 2, wherein a hol low shaft connects the second sun wheel with the said bearing in the end part and envelops the support.

4. Apparatus according to claim 2 or claim 3, wherein the centre of the roller is mounted on the support by a tumbler bearing carried by a supporting disc.

5. Apparatus according to claim 4, wherein a carrier part for a planet wheel which establishes a connection between the two sun wheels is non-rotatably coupled to the supporting disc.

6. Apparatus according to claim 5, wherein radially extending resilient strips are inserted between the supporting disc and the carrier part and engage in recesses in the disc and carrier part.

7. Apparatus according to any of claims 4to 6, wherein the supporting disc is clamped at its circum ference to an internal surface of the roller byfrusto- conical clamping means.

8. Apparatus according to claim 3, wherein the roller is rotatably mounted at one end on the said end part which is coupled to the hollow shaft by a rotating driving connection.

9. Apparatus according to claim 8, wherein the rotating driving connection is a sliding carriage ra diallydisplaceable in the end partandcontainsthe said bearing.

10. Apparatus according to claim 9, wherein a sleeve is rotatably mounted bythe carriage, which sleeve engages by means of gearteeth with an ad justmentwheel and engages by internal threading with an adjustment spindle which extends radially inwards and can be deflected but not rotated.

11. Apparatus according to any preceding claim, wherein the support is fixediy clamped at one end and the centre ofthe roller is mounted on the other, free end ofthe support.

12. Apparatus according to claim 2, wherein a sleeve fixed to the support carries the fixed first sun wheel and is in theform of a bearing sleeveforrotat- ing bearings disposed in the region of the centre of the roller.

13. Traverse motion apparatus constructed and arranged substantially as herein described and shown in the drawings.