AU613134B2 - Blind roller - Google Patents

Description

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AUSTRALIA

PATENTS ACT 1952 COMPLETE SPECIFICATION Form

(ORIGINAL)

FOR OFFICE USE C V

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Short Title: Ipt. Cl: Application Number: Lodged: Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art: TO BE COMPLETED BY APPLICANT C Name of Applicant: Address of Applicant: Actual Inventor: Address fcor Service: 4; CHARLES JOSEPH HESSE 83 Belford Road East Kew, Victoria 3102

AUSTRALIA

Charles Joseph Hesse GRIFFITH HACK CO., 601 St. Kilda Road, Melbourne, Victoria 3004, Australia.

Complete Specification for the invention entitled: BLIND ROLLER The following statement is a full description of this invention including the best method of performing it known to me:- C C

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2 BLIND ROLLER This invention relates to a blind roller, and in particular to an improvement to the blind roller disclosed in my copending Australian Patent Applicat 4 on 52115/86.

As explained in my above mentioned patent application conventional blind rollers suffer from problems associated with oscillatory tendencies when thrust and radial loadings are operating on a blind roller. In particular, in conventional blind rollers horizontal thrust motion causes the blind roller to move ~I~Llbarsnne~i~;,, ~I.1 1 -il-i l: I i I 3 to and fro which adversely affects the desired smoothness of the radial motion (that is the opening and closing motion of the blind).

The object of this invention is to overcome or at least reduce this problem.

The invention may be said to reside in a blind roller having an outer tube and a mandrel in the outer tube, a first bearing means disposed at one end of the mandrel between the mandrel and the outer tube and a second bearing means located at the other end of the mandrel between the mandrel and the outer tube and biasing means for biasing the mandrel or outer tube so that the outer tube can rotate relative to the mandrel against the bias of the hiasing means and under the influence of the biasing means, at least one of said bearing means having first and second bearing members, said first and second bearings members having intermeshing surfaces and at least one bearing disposed between the intermeshina surfaces.

Since at least one of the bearings has intermeshing surfaces with a bearing dispo-ed between the surfaces, the surfaces and therefore the first and second bearing members can be held relative to one another to thereby prevent movement of the mandrel in the longitudinal direction of the blind roller relative to the bearing means so that to and fro movement in the blind roller is prevented or at least reduced compared to conventional blind rollers.

Preferably both of said bearing means include intermeshing surfaces.

Preferably the intermeshing surfaces comprise zig zag surfaces on the first and second members of the bearing means. However, in alternative embodiments the meshing surfaces could be corrugated or of other shape.

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A preferred embodiment of the invention will be disclosed in further detail with reference to the accompanying drawings in which: Figure 1 shows a cross-sectional view through a blind roller embodying the invention; Figure 2 is a view of part of the blind roller according to a second eihbodiment of the invention; and Figure 3 shows a further embodiment of the invention.

With reference to Figure i, the blind roller comprises an outer tube 12 in which a pair of blocks 14 and 16 are arranged. The blocks 14 and 16 are adapted to rotate with the tube 12 about the longitudinal axis of the tube 12.

A mandrel 18 is located in the tube 12 and is journaled in the blocks 14 and 16 by bearing means 20 and 24. The bearing means 24 comprises a bore 23 which passes through the block 14 and a bearing member 25 which is connected to the mandrel 18 by a rivet 26 which passes through a stem portion 24a of the member 25 into which the mandrel 18 is received. The member 25 is provided with a zig zag outer surface which provides a plurality of first bearing surfaces 24b and a plurality of second bearing surfaces 2 4c.

The bore 23 which passes through the block 14 is provided with a complimentary shaped interior surface which has first and second bearing surfaces 14b and 14c which oppose the bearing surfaces 24b and 24c. A plurality of bearings 30 are arranged between the surfaces 24b and 14b and 24c and 14c. Bearings 32 are also provided at the apex of the surfaces 14b and between the surfaces 14c and 24b and 24c.

The member 25 is provided with a projection 34 which extends at the end of the blind roller and the projection 34 is provided with one half of a ratchet and pawl mechanism 36. The other half of the ratchet and pawl mechanism is arranged on the block 14. Such ratchet mechanisms are well known and therefore will rot be further described herein.

The bearing 20 is similar to the bearing 24 and comprises a member 40 in the form of a slee\ which receives the mandrel 18 and is provided with bearing surfaces 40a &nd 40b. Block 16 is provided with complimentary bearing surfaces 16a and 16b and bearings 42 are arranged between the surfaces in a similar manner to the bearings 30. Bearings 44 are also provided at the apex of the surfaces in a similar manner to the bearings j| 32. The end of the sleeve 40 may be provided with a vi bearing 45 or an idler pin at its ends which abuts a Aj hemispherical surface 47 at the.end of the block 16.

In order to insert the sleeves 34 and 16 into the blocks 24 and 20, the blocks 24 and 20 may be formed in two or more parts and assembled about the sleeves 24 Sand 40 before the blocks and mandrel 18 are inserted into the tube 12.

The block 16 is provided with a stem 46 which has connected thereto a spring 50. The spring surrounds the mandrel 18 and has its opposite end provided on an annular retaining member 52 which surrounds the mandrel 18.

The ei.bodiment of Figure 1 operates as follows.

When a blind is open oc unwound ifrom the roller blind the tube 12 together with the blocks 14 and 16 rotate.

Rotation of the block 16 causes the right hand end of the spring 50 to rotate thereby tensioning the spring 50 and allowing the blind to open against the bias of the spring The open blind is, of course, held in a desired position by the ratchet and pawl mechanism 36. The other end of thiS spring 50 is of course held by the member 52 which is fixed to the stem 24a of the block 24 by the rivet 26. Thus, the end of the spring connected to the member 52 is connected to the block 24 and is fixed

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T- Srelative to the block 14 whilst the end of the spring connected to the sleeve 46 rotates with the block 16 and the block 24 and tube 12. When the blind is released in the conventional manner it is caused to close or rewind by rotation of the outer tube 12 under the influence of the spring In the embodiment shown in Figure 2, the block 14 is provided with a corrugated inner surface which form first and second bearing surfaces 14b and 14c. The member 24 is also provided with a corrugated surface to provide complimentary first and second surfaces 24b and 24c. Bearings 30 are arranged at the curved apex between the surfaces and therefore roll on the portions of the surfaces 14b, 14c and 24b and 24c as the case may be as well as the curved apex joining these surfaces.

Since the complimentary bearing surfaces 14b and 24b and 14c and 24c together with the complimentary bearing surfaces 16a and 40a and 16b and 40b are arranged such that they face opposite ends of the roller blind, to and fro movement of the sleeves 24 and 40 relative to the blocks 14 and 16 is prevented. The mandrel is therefore held securely within the blocks 14 and "6 and therefore to and fro motion is minimized and stability of the system under tension is increased. Therefore, improved operating characteristics, especially under heaviar Sloadings, are obtained.

The zig zag or corrugated bearing si:faces on the members 14 and 25 and 16 and 40 define intermeshing surfaces which cause the block 14 and member 25 to intermesh and the block 16 and member 44 to intermesh.

The intermeshing of these members together with the bearings disposed between the relevant bearing surfaces also acts to prevent relative movement in the longitudinal direction of the bearing roller between the blocks 14 and the member 25 and the block 16 and the member 40. Furthermore the V-shape or corrugated shape of the bearing surfaces generally define a series of annular recesses on the blocks 14 and 16 as well as on the members 25 and 44. The annular recesses which also receive bearings also tend to prevent the block 14 and member 25 and block 16 and member 40 from moving relative to one another in the longitudinal direction of the blind roller. Thus, in the preferred embodiments of the invention to and fro motion within the blind roller is prevented.

The bearings 30, 32, 40 and 42 are preferably retained between the block 14 and member 25 and block 16 and member 40 by being embedded in the surtaces 14a, 14b or 16a, 16b of the block 14 or block 16 or in the surfaces 24b, 24c or 40a, 40b of the members 2- or 40 (as shown in my copending Application No. 52115/86) and roll on the complimentary surface.

Figure 3 shows a further embodiment which relates to the intermeshing of the block 14 and member In this embodiment the member 25 is provided with annular rinqs of bearings or annular integrally moulded ribs 60 and bearings 30 arranged in the block 25 engage and intermesh with the bearings or ribs 60 with a relatively tight fit to prevent longitudinal movement of the block 14 relative to the member The angle of the slope and the number of slopes in the zig zag or corrugated bearing surfaces can be varied to suit particular applications. Furthermore, when a blind is operated, the lines of force on the spring roller come from each end to the centre causing a deflection downwards and a tendency to whip on rotation.

By achieving maximum rigidity and anti-friction characteristics, the preferred embodiment of the invention will keep the above disadvantages to a minimum.

T- !ff Since modification within the spirit and scope of the invention may readily be effected by persons skilled within the art, it is to be understood that this invention is not limited to the particular embodiment described by way of example hereinabove.

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Claims (4)

1. A blind roller having an outer tube and a mandrel in the outer tube, a first bearing means disposed at one end of the mandrel between the mandrel and the outer tube and a second bearing means located at the other end of the mandrel between the mandrel and the outer tube and biasing means for biasing the mandrel or outer tube so that the outer tube can rotate relative to the mandrel against the bias of the biasing means and under the influence of the biasing means, at least one of said bearing means having first and seccnd bearing members, said first and second bearings members having o intermeshing surfaces and at least one bearing disposed 00 at 0 between the intermeshing surfaces. 00 Vt

2. The blind roller of Claim 1 wherein both of said bearing means include intermeshing surfaces. o,

3. The blind roller according to Claim 1 or 2 wherein the intermeshing surfaces comprise zig zag surfaces on the first and second members of the bearing means.

4. The blind roller of Claim 1 or Claim 2 wherein the intermeshing surfaces are corrugated. A blind roller substantially as hereinbefore described with reference to the accompanying drawings. i DATED this 2nd day of May 1991 CHIARLES JOSEPH HESSE By His Patent Attorneys GRIFFITH HACK CO. Fellows Institute of Patent Attorneys of Australia