GB2219191A

GB2219191A - Curtain pulling means

Info

Publication number: GB2219191A
Application number: GB8908724A
Authority: GB
Inventors: Helmut Jahn
Original assignee: BRATSCHI SILENT GLISS
Current assignee: BRATSCHI SILENT GLISS
Priority date: 1988-05-30
Filing date: 1989-04-18
Publication date: 1989-12-06
Anticipated expiration: 2009-04-18
Also published as: DE8904940U1; IT8920156A0; ATA88789A; IT1235436B; GB8908724D0; CH677596A5; GB2219191B; DE3912882A1; AT394489B; DE3912882C2

Description

n r 2219191 A curtain pulling means comprising a pulling member _guided

and displaceable in a hollow profiled rail 1 The invention relates to a curtain pulling means of the type comprising, guided and displaceable in a hollow profiled rail, a pulling member for moving a single or multi-element curtain, the ends of the pulling member being connected to each other and the pulling member having equidistantly disposed apertures engaged by teeth of a drive wheel.

A curtain pulling means of this type is already known from DE-A-2.7 29 491. This comprises a pulling member which is produced by extrusion and subsequent stamping. With this curtain pulling means, there is the difficulty that the friction of the pulling member in a curbed hollow profile rail and at the drive is comparatively great and that the production of the pulling member is.complicated and expensive. Long systems incorporating several curves are not viable to drive heavy curtains or they require a particularly powerful driving motor.

The invention is based on the problem of providing a curtain pulling means of the type described above which requires a substantially reduced driving power and which can in addition be more inexpensively produced. The curtain pulling means should be suitable for large installations- where there are bends and with an electrical rotary drive and should operate with comparatively little noise.

According to the present invention here is provided ja curtain pulling means of the type described, wherein the pulling member consists of curtain pulling means comprising, guided and displaceable in a hollow profiled rail, a pulling member for moving a single or multi- element curtain, the ends of the pulling member being connected o each other, and the pulling member having equidistantly disposed apertures engaged by teeth of a drive wheel, characterised in that the pulling member consists of individual bodies of comparatively hard and readily sliding synthetic plastics material and, disposed parallel with each other, two cords, each body having is ends fixed to respective cords. The individual bodies are preferably cylindrical and the cords made of steel strand.

Tests have shown that in the case of a conventional curtain system the power needed to move the curtain can be reduced by the invention from 27 Nm to 6 Nm. Manufacture of the curtain pulling means is substantially simpler and costs less, since the pulling tape can be produced in one operation,in an injection moulding process. The noise of movement is surprisingly low which is why the curtain pulling means according to the invention can also be used in conference rooms.

Claims

As a result of the further development according to Claim 4, kinking of the steel strand cords upon reversal about the drive wheel is avoided and the drive wheel can have a smaller radius than was hitherto conventional, without the effective life of the pulling means being noticeably shortened. The further developments according to Claims 2 and 5 ensure a particularly durable and strong connection between the bodies and the steel strand cords. A particularly robust and easily operated precursor is disclosed in Claim 7. By way of example, an embodiment of the invention is explained in greater detail hereinafter with reference to the accompanying drawings, in which: Fig. 1 is a perspective partial view of the curtain pulling means according to the invention, Fig. 2 is a further partial view of the curtain pulling means, Fig. 3 is a partial view of a drive wheel with a meshing pulling member, Fig. 4 is a cross-section through the curtain pulling means, Fig. 5 is a perspective view of the junction with the pulling member, Fig. 6 is a perspective view of the pulling member with a curtain precursor fixed to it and F19. 7 diagrammatically shows a curtain pulling means. A hollow profiled rail 5 adapted to be fixed to the ceiling of a room comprises two guide channels 7 and 8 in which a pulling member 1 is guided for longitudinal displacement. Provided at one end of the hollow profiled rail 5 is a housing 21 in which is mounted a drive wheel 10 which meshes with the pulling member 1. The drive wheel is driven by an electric motor M (Fig. 7). Disposed at the other end of the hollow profiled rail is a wheel U at which the endless pulling member 1 is deflected. The pulling member 1 comprises two parallel steel strand cords 3 which preferably consist of more than three strands to each of several wires. Equidistantly mounted on these are cylindrical bodies 2 which consist of a synthetic plastics material, preferably a comparatively hard and easily sliding synthetic plastics material such as for example Delrin or a polyamide of the nylon type. The bodies 2 are produced by an injection moulding process and the steel strand cords are integrally cast into them. At a length of about 13 mm, the ends 24 of the bodies 2 project about 2 mm beyond the steel strand cords 3. Between the bodies 2, the steel strand cords 3 are bright. As Fig. 4 shows, the bodies 2 have a longitudinal section which is similar to the profile section of the channels 7 and 8. The lateral clearance of the pulling member 1 in the channels 7 and 8 is small so that the pulling strip 1 can suffer only little compaction in a longitudinal direction in the hollow profiled rail 5. The pulling member 1 meshes with the drive wheel 10 as shown in Figs. 2 and 3. On either side of the teeth 11 which engage apertures 4 there are circular guide faces 13 on which rest those areas of the steel strand cords which are exposed between the bodies 2 when thesecords are in engagement with the drive wheel 10. The guide surfaces 13 are interrupted by depressions 12 which extend through between the teeth 11 and are engaged by the bodies 2. The guide surfaces 13 prevent the steel strand cords 3 becoming kinked or in any other way seriously stressed when deflected even around the comparatively small radius of the drive wheel 10. The passive deflecting or jockey wheel not shown here comprises corresponding guide faces and depressions. The ends of the pulling-member 1 are connected to each other by the connecting element 15 shown in Fig. 5. This is guided for displacement in the passage 6 or in the passage 9 and comprises projections 23 which engage apertures 4 in the pulling member 1. m z The curtain pulling means comprises sliding elements or rollers 14 which are guided for displacement in the channels 6 and 9. In each channel 6 and 9 there are four rollers 26 on which the sliding elements 14 run as they are displaced. Provided underneath each roller 26 is a guide stud 17 on the body 18 of the sliding element 14. Each sliding element also comprises a hole 27 into which is inserted a carrier 20 fixed on the curtain fabric 25. The sliding elements 14 move without hindrance in the channels 6 or 9 or are pushed by the connecting element 15. When two or more curtain elements are driven, then the precursor or driver 30 shown in Fig. 6 is provided. This consists preferably of synthetic plastics material and comprises two projections 31 which engage between the steel strand cords 3 on either side of the body 2. In the bottom region of the precursor 30 there is a hole 32 into which the carrier 20 can be inserted. The precursor 30 is likewise guided for a sliding displacement in a channel 6 or 9. If there are a pl.urality of curtain elements, then also correspondingly more precursors 30 may be provided. With the curtain pulling means according to the invention, it is possible to achieve the arrangement shown in Fig. 7. This has between_ the driving motor M and the jockey roller U three curves 40 and a rail length of 16 m. Even with a comparatively weak driving motor, a heavy curtain fabric or a heavy multiple-strip blind can be operated reliably and with little noise. CLAIMS:

1.- Curtain pulling means comprising, guided and displaceable in a hollow profiled rail (5), a pulling member (1) for moving a single or multielement curtain, the ends of the pulling member (1) being connected to each other, and the pulling member (1) having equidistantly disposed apertures (4) engaged by teeth (11) of a drive wheel (10), characterised in that the pulling member (1) consists of individual bodies (2) of comparatively hard and readily sliding synthetic plastics material and, disposed parallel with each other, two cords (3). each body (2) having its ends (24) fixed to respective cords (3).

2. Curtain pulling means according to Claim 1, characterised in that the individual bodies (2) are cylindrical and the cords (3) are made of steel strand.

3. Curtain pulling means according to Claim 2, characterised in that the steel strand cords (3) are cast into the bodies (2) which are produced by an injection moulding process.

4. Curtain pulling means according to Claim 2 or 3, characterised in that the distance between any two adjacent bodies (2) is greater than the distance between the steel strand cords (3).

5. Curtain pulling means according to any of Claims 2, 3 or 4 characterised in that the drive wheel (10) has on both sides of its teeth (22) guide surfaces (13) on which bear exposed portions of the steel strand cords (3) which are arcuately aligned and in that there are between the teeth (11) and extending transversely to the J I longitudinal direction of the pulling member (1), depressions (12) provided in the drive wheel (10) for the bodies(2).

6. Curtain pulling means according to Claim 3, characterised-in that the steel strand cords (3) consist of more than three strands for each of a plurality of wires.

7. Curtain pulling means according to any one of Claims 2 to 6. characterised in that the bodies (2) are substantially 13 mm long, the ends (24) of the bodies (2) projecting about 2 mm beyond the steel strand cords (3).

8. Curtain pulling means according to any one of Claims 1 to 7, characterised in that the pulling member (1) comprises at least one precursor (30) comprising two projections (31) which engage on either side of a body (2) between the cords (3).

9. Curtain pulling means substantially as hereinbefore described with reference to any of the Figures of the accompanying drawings.

Published 1989 at The Patent Office, State House. 66 71 High Holborn. London WClR4TP.F'arther copies maybe obtained from The PatentOffice Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1/87