GB2130472A

GB2130472A - Improvements relating to drawer slide arrangement

Info

Publication number: GB2130472A
Application number: GB08229948A
Authority: GB
Inventors: Richard N Munachen
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-10-20
Filing date: 1982-10-20
Publication date: 1984-06-06
Also published as: GB2130472B

Abstract

A drawer slide arrangement comprises a slide bar 1, a first set of rollers 5 adapted to be mounted on a drawer 4 and to run on a first track of the slide bar, and a second set of rollers 3 adapted to be mounted in a drawer enclosure 2 and to run on a second track of the slide bar. The slide bar is formed from a single strip of material, for example of mild steel, by rolling and has a profiled cross-section defining the tracks which are disposed vertically one above the other. The rollers of one of the sets have a convex tread and run on a concave track 17 and the rollers of the other set have a convex tread and run on a concave track 14. Advantageously an upper guide surface of one track and a lower guide surface of the other track can be formed by a common part of the cross-section of the slide bar which is so curved that it defines a concave guide surface on one side and a convex guide surface on the other side. <IMAGE>

Description

SPECIFICATION Improvements relating to drawer slide arrangements This invention relates to drawer slide arrangements of the kind used for example in document filing cabinets and desks and which allow full extension of the drawer from its enclosure whilst still being slidably supported.

The object of the invention is to provide a simple drawer slide arrangement which can be produced relatively cheaply.

According to the present invention a drawer slide arrangement comprises a slide bar, a first set of rollers adapted to be mounted on a drawer and to run on a first track of the slide bar and a second set of rollers adapted to be mounted on a drawer enclosure and to run on a second track of the slide bar, the slide bar being formed from a single strip of material and having a profiled cross-section defining said tracks which are disposed vertically one above the other, the rollers of one of said sets having a convex tread and running on a concave track, and the rollers of the other set of rollers having a concave tread and running on a convex track.

Advantageously, said slide bar is formed from metal strip by a rolling operation.

The slide bar preferably has a basically 'S' shaped cross-section, the upper loop of the S defining one of said tracks and the lower loop defining the other of said tracks. Thus both the tracks have upper and lower guide surfaces of either concave or convex form and the transition portion between the two loops is so curved that it defines a concave guide surface of one track on one side and a convex guide surface of the other track on its other side.

Said rollers preferably have ball bearings mounted on threaded stub shafts by which the rollers are mounted on the drawer and its enclosure.

One drawer slide arrangement in accordance with the invention and as embodied in a document filing cabinet will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a side sectional elevation of the filing cabinet, Figure 2 is a cross-section through the drawer slide arrangement, Figure 3 shows a perspective view of the slide bar, and Figures 4 and 5 show the two types of roller used.

Referring to the drawings, the drawer slide arrangement on each side of each drawer comprises a slide bar 1 which is supported by the filing cabinet body 2 through a pair of rollers 3 and which supports one side of the drawer 4 through rollers 5.

The rollers 3 and 5 have ball bearings 6 mounted on threaded stub shafts 7 by means of which the rollers 3 and 5 are fixed to the cabinet body 2 and the drawer 4 respectively in any convenient manner. For example, in the case of wooden filing cabinets the shafts 7 are screwed into inserts 8 of plastics material which snap fit into bores in the body 2 and drawer 4. The length of the threaded shafts 7 is sufficient for washers to be fitted on them so that the spacing of the rollers 3 and 5 from the body 2 and the drawer 4 into which they are fixed can be varied and yet still provide enough thread for secure fixing.

Thus a limited adjubtment is provided in the case of incorrectly manufactured drawers and cabinet bodies.

The slide bar 1 is in this example formed by rolling single blank of mild steel strip into a basically 'S' shaped cross-section as shown in Fig. 2. The upper loop of the 'S' defines a track 9 for the rollers 5 and the lower loop of the 'S' defines a track 10 for the rollers 3.

The rollers 3 have concave treads 1 2 and the lower track 10 has upper and lower guide surfaces 1 3 and 14 of complementary convex form which locate in the concave treads 1 2 to constrain the rollers 3 against lateral movement relatively to the slide bar 1. The rollers 5 have convex treads 1 5 and the upper track 9 has upper and lower guide surfaces 1 6 and 1 7 of complementary concave form in which the treads 1 5 locate to constrain the rollers 5 against lateral movement relatively to the slide bar 1.The upper guide surface 1 3 of the lower track 10 and the lower guide surface 1 7 of the upper track 9 are advantageously formed by a common part of the cross-section of the slide bar, the upper concave surface and the lower convex surface being formed simultaneously by a suitable curving of this part of the cross-section in the rolling operation. This has the added advantage that the rack 9 is directly above the track 10 so that there is no transverse moment acting on the slide bar 1 through the rollers 3 and 5 tending to twist it.

The slide bar 1 is so shaped in cross-section that it has planar outer vertical portions 1 8 and 1 9 which are spaced from the cheeks of the rollers 3 and 5, so that the latter do not bind with the portions 1 8 and 1 9. This spacing is for example 1.5 mm. Also the slide bar 1 at its upper and lower margins is bent round to provide horizontal strengthening flanges 21 and 22 which tend to prevent lateral deformation of the slide bar.

As shown in Fig. 3, the slide bar 1 is formed by the rifling operation with end stops 23 and 24 for the rollers 5 and end stop 25 for the rear rollers 3. It is also formed with a cut out 26 through which, by suitable'mani- pulation of the drawer 4, the rollers 5 can pass to permit lifting of the drawer 4 out of the cabinet body 2.

In use of the slide arrangement, as the drawer 4 is pulled out of the cabinet body 2, the rollers 5 run along the track 9 until the front roller comes up against the end stop 24 and the slide bar 1 itself runs over the rollers 3 until the rear roller 3 comes up against the stop 25. The situation then is as shown by the lower drawer 4 in Fig. 1. As the drawer is pushed back in again the reverse operation takes place, the inner roller coming up against the stop 23, the final situation being as shown by the upper drawer in Fig. 1. It has been found that with the above described drawer slide arrangement there is virtually no drop or downward deflection of the extended drawer.

Claims

1. A drawer slide arrangement comprising a slide bar, a first set of rollers adapted to be mounted on a drawer and to run on a first track of the slide bar, and a second set of rollers adapted to be mounted in a drawer enclosure and to run on a second track of the slide bar, the slide bar being formed from a single strip of material and having a profiled cross-section defining said tracks which are disposed vertically one above the other, the rollers of one of said sets having a convex tread and running on a concave track and the rollers of the other set having the convex tread and running on a concave track.

2. A drawer slide arrangement according to Claim 1 and formed from metal strip by a rolling operation.

3. A drawer slide arrangement according to Claim 1 or 2, wherein said slide bar has a basically 'S' shaped profile, the upper loop of the 'S' forming one of said tracks and the lower loop of the 'S' forming the other of said tracks, both the tracks having upper and lower guide surfaces of convex or concave form and the transition portion between the loops is so curved that it defines a concave guide surface on one side and a convex guide surface on the other side.

4. A drawer slide arrangement according to Claim 3 wherein the upper and lower margins of said strip are bent to form strengthening flanges extending horizontally.

5. A drawer slide arrangement according to Claim 3 or 4, wherein the outer side of said loops are planar and extend vertically at a spacing from the cheeks of the rollers.

6. A drawer slide arrangement according to any preceding Claim, wherein the rollers have bearings mounted on threaded stub shafts by which the rollers are adapted to be mounted on a drawer or in its enclosure.

7. A drawer slide arrangement substantially as hereinbefore described with reference to the accompanying drawings.