GB2149296A - Turntable - Google Patents

Abstract

A turntable device comprises a base (2) and a load-carrying platform (1), said base and platform having interengaging annular bearing surfaces to enable the platform to be supported by, and rotate on, the base. In one arrangement, the base has an upstanding rib (12) received in a recess (10) in the platform and the angle through which the platform can be rotated is limited by pins 21 abutting against stop members 23. <IMAGE>

Description

SPECIFICATION Turntable This invention relates to a turntable device which is useful for general purposes, for example for positioning under a television set or other item of household equipment to enable it easily to be rotated between different positions.

Turntable devices are known but in general they suffer from one or other of two drawbacks. Either they are of complex construction employing, for example, ball or roller bearings, and hence are expensive, or they are of very lightweight and crude construction able only to carry light loads such as small transistor radios.

We have now devised a turntable device which can carry relatively heavy loads such as television sets and yet which is of simple construction and hence relatively inexpensive.

In accordance with the present invention, a turntable device comprises a base and a load carrying platform, said base and platform having interengaging annular bearing surfaces to enable the platform to be supported by, and rotate on, the base.

Preferably, the base is itself annular and is provided, on its underside, with one or more friction pads or rubber studs, for example, to enable it to grip and remain stationary on a support surface on which the device is placed in use.

In a preferred embodiment of the invention, the platform is also annular and generally coextensive with the annular base. Optionally, a circular disc may be provided to fit within the platform annulus to form therewith a generally planar supporting surface. The upper surface of the platform is preferably provided with one or more friction pads or rubber studs, for example, to enable it better to engage an article placed thereon.

The bearing surfaces on the two members, i.e. on the base and on the platform, can be provided in a number of ways. We prefer to use an upstanding annular rib on one member. Preferably, but not essentially, there will be a complementary annular recess formed on the other member, the rib being received in the recess. In such an arrangement, the recess can be made only slightly wider than the rib, so that lateral movement of the two members is prevented by engagement of the rib in the recess. The recess can be in the form of a channel defined by walls upstanding from the respective member, or can be a groove formed in the member, for example.

More than one upstanding rib can be used if desired, thus to provide two or more bearing surfaces on a member.

We prefer to use continuous annular bearing surfaces but, if desired, one of the surfaces can be discontinuous e.g. a plurality of rib sections, spaced apart, can be provided, the sections lying on a common circle, i.e.

being sections of a continuous annulus.

Preferably, the base and pltform are both plastics mouldings, the bearing surfaces being integrally moulded parts thereof. We prefer to use polyamides (e.g. Nylons) for this purpose, but other synthetic plastics materials may be used. The material used in such cases must be such as to provide the desired bearing surfaces of sufficient strength with appropriate low friction therebetween so that the loaded platform is smoothly and easily rotatable on the base.

According to a further preferred feature of the invention, means are provided for limiting the angle through which the platform can be rotated relative to the base. The purpose of this is to prevent the turntable inadvertently being rotated through too great an angle, thus for example damaging the article thereon.

Preferably, any rotation limiting arrangement is adjustable so that it can be set in accordance with the particular use to which the turntable is to be put. One simple rotation limiting arrangement comprises a stop member formed in, or fixed in, the base, and one or more (usually two) pins or the like insertable in the platform to engage against the stop at the chosen limits of rotation. By providing a series of bores in the platform at spaced intervals, into which the pin(s) can be inserted, the degree of rotation can be preset and corresponds to the angular separation of the pins. Other arrangements can, of course, be used.

The base and the platform are preferably positively locked together to prevent inadvertent disassembly. This can be achieved in a number of ways. We prefer the two members to be a snap-fit together and, for this purpose, one member may have a radial flange which, on assembly of the two members, is forced beyond a radial protrusion on the other member. For example, the platform may have an outer dependent skirt with an internal flange, or series of spaced internal projections, which snap over a corresponding radially outward flange or series of projections on the base member. The locking arrangement must not interfere with free rotation of the platform relative to the base and, in the above example, there will be a clearance between the respective flange(s) or projection(s) in the assembled turntable.

In order that the invention may be more fully understood, one embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 is a view of a turntable device of the invention; and Figures 2 and 3 are, respectively, sections on the lines A-A and B-B of Fig. 1.

Referring to the drawings, the turntable comprises two annular members, namely a load-bearing platform 1 and a base 2. The upper surface 3 of platform 1 has a series (six are shown) of PVC pads 4 thereon to grip an article placed on surface 3. Symmetrically disposed around surface 3 are bores 20 the purpose of which is described hereinafter, one bore 20' having a peg or pin 21 therein.

As can be seen from the sectional views, platform 1 includes an outer dependent skirt 5 having at its lower edge an inwardly directed flange 6. Dependent from the underside of the platform 1 are two walls, 7,8, defining a channel whose bottom surface 10 constitutes a bearing surface.

The base 2 comprises a bottom portion 11 with an upstanding rib 12 whose upper surface constitutes a bearing surface. Rib 12 is received in the channel between walls 7 and 8 of platform 1. Base 2 also has an upstand ing inner wall 14 whose upper surface 1 5 may also be a bearing surface, it being located adjacent inner portion 26 of platform 1.

At spaced intervals around its periphery, the bottom 11 of base 2 has bevelled outer projections 16. Base 2 has a series of PVC grip pads 1 7 on its underside.

Platform 1 and base 2 are plastics mouldings made of Nylon. They are fitted together to form a turntable of the invention by placing platform 1 directly over base 2, and pressing platform 1 towards base 2 to cause flange 6 to ride over and beyond projections 1 6 on base 2. The natural resilience of the plastics material thus provides a snap-fit locking arrangement, projections 1 6 preventing disassembly by engagement with flange 6.

In order to provide limits on the angular rotation of platform 1, a pin 21 is inserted in hole 20' in platform 1 (see Fig. 3). The pin extends downwardly into the space 22 between rib 1 2 and wall 14 of base 2. Moulded or tixed within space 22 is a stop member 23. When platform 1 is rotated relative to base 2, pin 21 travels in the annular space 22 until it abuts the stop 23 whereupon further rotation in that direction is prevented.

A second pin (not shown) disposed in another bore 20 will likewise engage stop 23 when the platform is rotated in the opposite direction.

The inner side portion 26 of platform 1 is recessed to provide an annular ledge 27 upon which a circular disc may be mounted to fill the top of the platform annulus to provide a larger load bearing surface if desired.

Whilst we have described the base and platform made of plastics material, either or both can be made of another material, e.g. a metal such as steel. In this case, the bearing surfaces may be formed of the same or another material, e.g. a plastics material. The invention further includes a turntable as herein before described which includes a material such as an annular insert to be provided directly between the bearing surfaces, for example to reduce friction. Examples of such materials are fluorinated polymers such as PTFE.

Claims (17)

1. A turntable device which comprises a base and a load carrying platform, said base and platform having inter-engaging annular bearing surfaces to enable the platform to be supported by, and rotate on, the base.

2. A device according to claim 1, wherein the base is annular.

3. A device according to claim 2, wherein the platform is annular and is generally coextensive with the annular base.

4. A device according to claim 3, which also includes a circular disc-like member ar ranged to fit within the platform annulus to form therewith a generally planar supporting surface.

5. A device according to any of claims 1 to 4, wherein one or both of the underside of the base and the upper surface of the platform is (are) provided with one or more regions to provide grin in use.

6. A device according to any of claims 1 to 5, wherein one of said bearing surfaces comprises an upstanding annular rib on the base or the platform.

7. A device according to claim 6, wherein the other of said base or platform comprises an annular recess complementary to said rib, the rib being received in the recess.

8. A device according to claim 7, wherein the said annular recess is in the form of a channel defined by walls upstanding from the respective member.

9. A device according to any preceding claim, wherein the annular bearing surfaces are continuous.

10. A device according to any preceding claim, wherein the base and platform are both plastics mouldings, the bearing surfaces being integrally moulded parts thereof.

11. A device according to any preceding claim which includes means for limiting the angle through which the platform can be rotated.

1 2. A device according to claim 11, wherein said limiting means is adjustable to vary the angle through which the platform can be rotated.

1 3. A device according to any of claims 1 to 12, wherein the base and the platform are positively locked together to prevent inadvertent disassembly.

14. A device according to claim 1 3, wherein the base and platform are a snap-fit together.

1 5. A device according to any of claims 1 to 14, which includes a material between the bearing surfaces.

1 6. A device according to claim 1 5, wherein the material is of fluorinated polymer.

17. A turntable device substantially as herein described with reference to the accompanying drawings.