GB2211819A - Expandable coiling spool for metal strips - Google Patents

Description

2211819 EXPANDABLE COILING SPOOL FOR METAL STRIPS This invention relates

to an expandable coiling spool for metal strips, more particularly - but not exclusively non-ferrous metal strips, having an entry cone for an inwardly movable coiling mandrel at each endr a core which can be gripped between the coiling mandrels, a jacket, and expansion members between the core and the jacket, the jacket being divided into expansion segments supported on the expansion members, and the expansion segments being free to move radially outwards against the action of return springs.

There is a known coiling spool of this type, in whi.ch the ends of each expansion segment are adapted as entry cones f or the coiling mandr el s and the core consists of a central tube. At both ends of this central tube there are expansion cylinders and compression pistons. for actuation by the cAling mandrels. Furthermore, the central tube has radially disposed housings in which are located radially guided bearing members for the expansion segments. Hydraulic fluid ducts extend inside the central tuber from the expansion cylinders to the housings or to bearing members disposed therein, for actuation by the hydraulic fluid. Moreover, the expansion segments have slide-pieces spaced at prescribed distances on their inner sides, which are guided in radially disposed slideways with interposed return springs or bolts. These slideways are disposed in bushes attached to the central tube. In order to carry out the expansion process in this known embodiment, the expansion members must be supplied with pneumatic or hydraulic actuating fluid. This is a complicated arrangement, both constructionally and correspondingly in manufacturing requirements, and moreover it is prone to failure (cf. DD-PS 128 853).

There is also a known floating-support coiling spool in which the expansion segments are supported on the core with interposed expansion members. The expansion members consist of intermeshing sawtooth expansion strips, and the outer strips can be displaced axially relative to the inner strips. Axial displacement produces an expansion of the expansion segments supported on the expansion members. Th e undersides of the expansion segments carry guide strips which engage in axially disposed slidways in the core, and return springs are mounted in the guide strips, on threaded bolts anchored in the core. This known coiling spool is unsuitable for use in coilers for the coiling of metal strips in general or non-ferrous metal strips in particular,, because such coilers have coiling mandrels which move towards and away from each other to grip and release the coiling spools, and the mandrels themselves initiate the expansion process (cf. US-PS 30 85 763).

The object of the invention is to provide an expanda.le coiling spool for metal strips, of the type initially described but of outstandingly simple yet functionally reliable construction,, more particularly no longer requiring pneumatic or hydraulic actuating fluids.

According to the present invention in a coiling spool of the type initially described the core has an outer tube telescoping on an inner tube, the remote tube ends carry the entry cones for the coiling mandrels the expansion segments can more radially in guides in the outer tube, and when the outer tube telescopes over the inner tube as the spool is gripped between the coiling mandrels the expansion members urge the expansion segments radially outwards in succession. These features of the invention have the result that expansion and contraction of the coiling spool are brought about by purely mechanical means and hence without the aid of pneumatic or hydraulic actuating fluids. This simplifies on the one hand the manufacture of the coiling spooli, on constructional grounds, and on the other hand the expansion processes, on functional grounds.

Further and preferred constructional features of the invention will now be described. Thus, each remote end of the.inner tube and the outer tube can have a retaining flange for the expansion members.. which are thus as it were embedded between the retaining flanges. It is preferable to provide axial return springs between the inner tube and the outer t ube, distributed round the periphery and extending lengthwise of the tubes. The return springs aid the contraction of the coiling spool and hence the return of the inner tube and the outer tube to their relatively extended positions upon retracting the coiling mandrels. The expansion members on the outer surface of the outer tube can have wedges and support strips running longitudinally along the tube, the support strips having inclined faces interacting with the wedges. The angle of the wedges and faces is preferably slightly less than the self-locking or friction angle, so as to facilitate contraction. One alternative embodiment of the invention has the outer tube divided into lengths,, between which are provided expansion members in the f orm of rubber or elastic plastics rings with interposed compression rings if required. In thi S case, the rubber or plastics rings contract spontaneously, since they can both expand and contract radially. The use of radial springs as expansion members is also conceivable.

In a coiling spool in which the expansion segments have guide shoes placed at prescribed spacings on their inner sides, the guide shoes slide in axial slideways in the outer tuber and the radial return springs are disposed in the intrinsically known manner in the guide shoes on bolts, anchored in the inner tube. The radial spring forces can easily be adjusted so that the inner and outer tubes spo.ntaneously return to their initial positions after release, provided that the angle of the expansion wedges and inclined faces is below the self-locking limit. In this case, axial return springs spaced round the periphery of the tubes becomes superfluous. The radial return springs preferably consi.st of stacked plate springs.

An embodiment of the invention will now be described, by way of example only. with reference to the accompanying drawings, in which:- Figure 1 is a schematic longitudinal section through a coiling spool in accordance with the invention, one half being in the contracted -state and the other half when expanded; Figure 2 is an enlarged cross-section through the spool of Figure 1, but showing only one expansion segment in the contracted position; Figure 3 is a scrap view corresponding to part of Figure 2 with the expansion segment in the expanded position; Figure 4 is a fragmentary section on the line IV-IV of Figure 2; and Figure 5 is an enlarged fragmentary section corresponding to part of Figure 1 but showing a return spring.

Figuresl and 2 show anexpandable coiling spool 1 for metal strips, more particulalry non-ferrous metal strips; however, it is within the scope of the invention to use the coiling spool 1 for the coiling of other strips, such as plastics strips f or exam pl, e. In basic construction, the coiling spool 1 has a core which can be gripped between inwardly movable coiling mandrels 2, a jacket, andexpansion members between the core and the jacket. The core has an outer tube 4 which telescopes on an inner tube 3 and the remote tube ends have entry cones 5 for the coiling mandrels 2. The jacket is divided into expansion segments 7 supported on the expansion members 6. The expansion segments 7 are guided to move radially with respect to the outer tube 4, against the action of return springs 8. When the outer tube 4 is forcibly telescoped on the inner tube 3 by gripping between the coiling mandrels 2, the expansion segments 7 are urged radially outwards i'n unioon by the expansion members 6, until the spool is fully expanded. Each remote end of the inner tube 3 and the outer tube 4 has a retaining flange 9 for the expansion members 6. Return springs 10 (see particulalry Figure 5) are provided between the inner tube..3 and the retaining flange 9 of the outer tube 4, distributed round the periphery and extending lengthwise 6 of the tubes.

The expansion members 6 on the outer surf ace of the outer tube 4 have wedges 6a and support strips 6b running longitudinally along the tube. The expansion wedges 6a can be secured to the outer tube 4 by various means, tightf itting groove joints being used in the embodiment shown (see Figures 2 and 3). The expansion strips 6b have inclined faces 11 interacting with the expansion wedges 6a, the angle of the expansion wedges 6a and faces 11 preferably being below the self-locking limit. The inclined f aces 11 are machined like sawteeth in the inner sides of the expansion strips 6b. The inner sides of the expansion segments-7 car.ry guide shoes 12 (see also Figure 4) at a prescribed spacing# which guide shoes slide in axially disposed slideways 13 in the outer tube 4. The return springs 8 are disposed in the guide shoes 12 on bolts 14, for example threaded bolts screwed into the inner tube 3. The crosssection of the expansion segments 7 in the'vicinity of the guide shoes 12 is mushroom-like#, with support on both sides from the strips 6b of the expansion members 6. It will be apparent that the jacket in the embodiment shown is divided longitudinally into four expansion segments 7.

7

Claims (7)

1. An expandable coiling spool for metal strips having an entry cone for an inwardly movable coiling mandrel at each end, a core which can be gripped between the coiling mandrelsr a jacket, and expansion members between the core and the jacket, the jacket being divided into expansion segments supported on the expansion members, and the expansion segm.ents being f ree to move radially outwards against the action of return springs, wherein the core has an outer tube telescoping on an inner tube, the remote tube ends carry the entry cones for the coiling mandrels, the expansionsegments can move radially in guides in the outer tube, and when the out=r tube telescopes over the inner tube as the spool is grippedbetween the coiling mandrels the expansion members urge the expansion semgnets radially outwards in uni son.

2. A coiling spool as in Claim 1, wherein each remote end of the inner tube and the outer tube has a retaining flange for the expansion members.

3. A coiling spool as in Claim 1 or Claim 2, wherein axial return springs are provided between the inner tube and the outer tube,, distributed round the periphery.and extending lengthwise of the tubes.

4. A coiling spool as in any one of Claims 1 to 3, wherein the expansion members on the outer surface of the outer tube have wedges and support strips running longitudinally along the tuber the support strips having inclined faces interacting with the wedges.

5. A coiling spool as in any one of Claims 1 to 3, wherein the outer tube is divided into lengths,, between which are provided expansion members in the f orm of rubber or elastic plastics rings.

6. A coiling spool as in any one of Claims 1 to 4, in which the expansion segments have guide shoes placed at prescribed spacings on their inner sides, and wherein the guide shoes slide in axial slideways in the outer tube, and radial return springs are disposed in the intrinsically known manner on bolts which are anchored in the inner tube.

7. An expandable coiling spool for metal strip. substantially as hereinbefore described with reference to th= accompanying drawings.

Published 1989 atThe Patent Office. StateRouse,8671 High Holborn. London WCH:L4TP.Further copies maybe obtained from The Patentoffice. Sales Branch, St Mary Cray, Orpington, Kent BM 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent. Con. 1187