GB2264173A

GB2264173A - Apparatus for mounting an instrument case on a support.

Info

Publication number: GB2264173A
Application number: GB9202039A
Authority: GB
Inventors: Peter Taylor
Original assignee: Delco Electronics Overseas Corp
Current assignee: Delco Electronics Overseas Corp
Priority date: 1992-01-31
Filing date: 1992-01-31
Publication date: 1993-08-18
Anticipated expiration: 2012-01-31
Also published as: GB9202039D0; GB2264173B

Abstract

Apparatus for mounting an instrument case 10 on a support 20 comprises two pairs of legs 14,16 at a front end of the instrument case, and a pair of retaining members 22 and a pair of stressing members 24 on the support 20. The stressing members 24 include a raised surface and a ramp and abutment shoulder on respective sides of the raised surface. The raised surface of each stressing member 24 causes its respective leg 16 to be biased upwardly against the retaining force provided by the retaining members 22, thereby providing stress between the instrument case 10 and the support 20. The apparatus can secure the instrument case 10 tightly to the support 20 without the need for screws or other fixing means. <IMAGE>

Description

APPARATUS FOR MOUNTING AN INSTRUMENT CASE ON A SUPPORT The present invention relates to apparatus for mounting an instrument case on a support for use, for example, in mounting a gauge case on a dial support in an instrument cluster for a vehicle.

In known instrument clusters, a gauge case comprising a plurality of lugs located adjacent its front surface is mounted on a dial support by means of screws which pass through apertures in the lugs and into the dial support. Although this can provide a strong connection between the gauge case and the dial support, in practice it is possible to damage the dial support or gauge case when tightening the screws. This has sometimes led to the screws being fitted loosely, which usually results in the gauge case coming loose from the dial mounting, causing damage to the gauge coil.

Attempts have been made to replace the screw-type fitting with a conventional bayonet-type fitting. However, these attempts have generally been unsuccessful because of the need for a tight fit between the gauge case and the support. They have generally led either to the gauge case being loose on the dial support or to the fitting being damaged due to an excessive amount of stress being applied thereto.

The present invention seeks to provide improved apparatus for mounting an instrument case to a support.

According to an aspect of the present invention, there is provided apparatus for mounting an instrument case on a support comprising a plurality of first engagement elements and at least one second engagement element spaced from one another around the periphery of the instrument case, a plurality of retaining members provided on the support and adapted to engage respective first engagement elements so as to retain the instrument case on the support, and at least one stressing member spaced from the retaining members and adapted to engage the or a respective second engagement element and to provide stress between the instrument case and the support.

It has been found that separating the retaining and stressing members can provide a much improved fitting and can prevent damage to the fitting during its use.

In an embodiment, the stress between the instrument case and the support is provided by resiliently deforming the instrument case to bias the first engagement elements thereof against their respective retaining member.

The apparatus preferably comprises a pair of retaining members and a pair of first engagement elements. The first engagement elements may be disposed substantially opposite one another relative to the instrument case. The apparatus preferably also comprises a pair of stressing members and a pair of second engagement elements, the second engagement elements being disposed substantially opposite one another relative to the instrument case. Such arrangement has been found to provide the best fit of the instrument case on the support.

In an embodiment, the or each stressing member comprises a surface raised above the level of the support and adapted to cause the second engagement element to deform the instrument case resiliently, thereby to provide stress between the instrument case and the support. The raised surface of the or each stressing member advantageously has a height of approximately 0.3 millimetres relative to the support.

Preferably, the apparatus comprises a guiding rib adapted to align the instrument case relative to the support and to guide the movement of the engagement elements into engagement with their respective retaining or stressing member. The guiding rib may be adapted to engage a portion of each of the first and second engagement elements.

According to another aspect of the present invention, there is provided a support for supporting an instrument case comprising two or more retaining members adapted to engage respective first engaging elements of an instrument case to retain the instrument case thereon, and at least one stressing member spaced from the retaining members and adapted to engage a second engaging element of the instrument case to provide stress between the instrument case and the support.

It has been found that the present invention can be used with standard gauge cases, enabling it to be relatively inexpensive.

An embodiment of the present invention is described below, by way of illustration only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an embodiment of apparatus having respective parts fitted to a gauge case and dial support; Figure 2 is a plan view of the parts of the apparatus provided on the dial support of Figure 1; Figure 3 is a plan view of the gauge case of Figure 1, not showing terminals thereof; Figure 4 is a side elevational view of part of the gauge case of Figure 1; Figure 5 is a side elevational view of the gauge case of Figure 1 mounted on the dial support; Figure 6 is a cross-sectional view of a leg of the gauge case and a stressing member of the dial support; and Figure 7 is a cross-sectional view of a retaining element of the dial support, taken along line 7-7 of Figure 2.

Referring to Figure 1, a gauge case 10 housing a coil-type gauge of known form includes a plurality of legs arranged in first and second pairs 14,16 and extending from a front end of the gauge case 10. An aperture (not shown) is also provided in the front end of the gauge case 10, through which passes a gauge pin 18 used for supporting a dial pointer, in conventional manner. A plurality of electrical terminals 12 extend out of a rear surface of the gauge case.

The gauge case 10 is typically of metal, although may be of any other suitable material.

A dial support 20, typically made of a plastics material, includes first and second retaining members 22 and first and second stressing members 24 disposed around a central aperture 26 through which passes the gauge pin 18. The retaining members 22 are disposed substantially opposite one another relative to the aperture 26. Similarly, the stressing members 24 lie substantially opposite one another relative to the aperture 26 and along a line substantially perpendicular to the line along which the retaining members 22 lie.

Each retaining member 22 comprises three walls 28,30,32 substantially perpendicular to one another and forming three sides of a cuboidal structure. The dial support 20 provides a base for the structure, while the other two sides are open.

One of these open sides faces the aperture 26, while the second open side is disposed upstream of the other sides of the structure relative to the direction (shown by the arrows 34) in which the legs 14,16 of the gauge case 10 rotate during fitting of the gauge case to the dial support 20.

The top wall 32 of each retaining member 22 is provided with an aperture for receiving a screw (not shown), if this is desired. The top walls shown in Figures 2, 5 and 7 are not provided with such apertures.

The components of the fitting which are provided on the dial support 20 are shown in plan view in Figure 2. As can be seen, rear walls 28 of the retaining members 22 and the stressing members 24 are curved so as to ease fitting of the gauge case 10 to the dial support 20. The dial support 20 is also provided with an annular rib 36 around two to three millimetres high and substantially concentric with the aperture 26. In use, this rib 36 facilitates the location of the legs 14 and 16 of the gauge case 10 during its fitting to the dial support 20, as is described below in connection with Figure 3.

Referring to Figure 3, the legs 14,16 of the gauge case 10 extend into the radial perimeter of the gauge case, and are provided with inner surfaces 38 contoured to a circle of a diameter slightly larger than the diameter of the annular rib 36.

Thus, when the gauge case is fitted onto the dial support 20, it is located accurately relative to the aperture 26 and the retaining and stressing members 22,24. Furthermore, as the gauge case is rotated to the locking position (that is, clockwise as seen in Figures 2 and 3), the inner surfaces 38 of the legs 14,16 are guided accurately along the annular rib 36 to their respective retaining or stressing member 22,24.

It has been found that this feature can significantly facilitate the fixing of the gauge case to the dial support and can substantially reduce the risk of damage to the components of the fitting during this operation.

As can be seen in Figure 4, each of the legs 14,16 of the gauge case 10 extends substantially an equal amount in the axial direction of the gauge case 10, so that the lower surfaces 40 of the legs 14,16 all lie substantially in the same plane, the purpose of which is described below in connection with Figures 5 and 6.

In Figure 5, the gauge case 10 is shown fitted to the dial support 20. As can be seen, the stressing member 16 is raised slightly above the level of the dial support 20 and forces its respective leg 16 to be above the level of the legs 14 by resiliently deforming the gauge case 10 against the retaining force provided by the retaining members 22. This causes the legs 14 to be biased against the top wall 32 of their respective retaining member 22, thereby providing the desired stress between the gauge case 10 and the dial support.

The structure of the stressing members 24 is better seen in Figure 6. Each member 24 comprises a surface 50 which is raised above the surface of the dial support 20 by a distance X, which is preferably about 0.3 millimetres. A ramp 52 separates one side of the raised surface 50 from the dial support 20 and also provides a first stop 54 having a height Y of approximately 0.6 millimetres relative to the dial support 20.

In use, this first stop 54 prevents the leg 16 of the gauge case 10 from moving off the raised surface 50. The surface 56 of the first stop 54 is disposed at an angle of around 450 relative to the raised surface 50 to enable the leg 16 to be moved off the stressing member 24 should it be desired to remove the gauge case 10 from the dial support 20.

In embodiments in which it is desired to prevent the removal of the gauge case 10 from the dial support 20, the surface 56 may be substantially perpendicular to the raised surface 50.

At the other end of the raised surface 50, there is provided a second stop 58.

During fitting, as the gauge case 10 is rotated relative to the dial support 20, the legs 14 move into the retaining members 22 while the legs 16 move along the ramp 52 of their respective stressing member 24 and onto the raised surface 50, thereby causing the gauge case to deform slightly.

In the embodiment shown, the disposition of the stressing members 24 relative to the retaining members 22 is such that the legs 16 will have engaged the ramps 52 by the time the legs 14 reach the opening of their respective retaining member 22. In order to facilitate the entry of the legs 14 into their respective retaining members 22, a portion of the inner surface of the upper wall 32 of each retaining member 22 is tapered (Figure 7). Thus, although each leg 14 will be urged upwardly relative to the dial support 20 by the fact that the legs 16 will have already engaged the ramps 52, the tapered opening of each retaining members 22 will enable its respective leg 14 to move into it easily and to be gradually biased back towards the dial support 20.

Of course, by appropriate placement of the stressing members 24 or design of the retaining members 22, it can be ensured that the legs 14 have already begun moving into their respective retaining member 22 by the time the legs 16 engage the ramps 52.

The specific design of retaining members 22 and stressing members 24 shown in the drawings is intended for use with dial supports which act as light guides, guiding light from one or more light bulbs to the display area of an instrument cluster so as to illuminate the graphic symbols on the instrument displays. The design shown minimises the effect of the members 22,24 on the passage of light through the support 20.

Claims

CLAIMS:

1. Apparatus for mounting an instrument case on a support comprising a plurality of first engagement elements and at least one second engagement element spaced from one another around the periphery of the instrument case, a plurality of retaining members provided on the support and adapted to engage respective first engagement elements so as to retain the instrument case on the support, and at least one stressing member spaced from the retaining members and adapted to engage the or a respective second engagement element and to provide stress between the instrument case and the support.

2. Apparatus according to claim 1, comprising a pair of retaining members and a pair of first engagement elements.

3. Apparatus according to claim 2, wherein the first engagement elements are disposed substantially opposite one another relative to the instrument case.

4. Apparatus according to claim 1, 2 or 3, comprising a pair of stressing members and a pair of second engagement elements.

5. Apparatus according to claim 4, wherein the second engagement elements are disposed substantially opposite one another relative to the instrument case.

6. Apparatus according to claim 5, comprising a pair of first engagement elements lying along a line substantially perpendicular to a line along which the second engagement elements lie.

7. Apparatus according to any preceding claim, wherein the or each stressing member comprises a surface raised above the level of the support and adapted to cause the second engagement element to deform the instrument case resiliently, thereby to provide stress between the instrument case and the support.

8. Apparatus according to claim 7, wherein the raised surface of the or each stressing member has a height of approximately 0.3 millimetres relative to the support.

9. Apparatus according to claim 7 or 8, wherein the or each stressing member comprises a ramp at a first end of the raised surface.

10. Apparatus according to claim 9, wherein the ramp extends beyond the raised surface and includes a stop adapted in use to prevent an engagement element on the raised surface from moving off the raised surface in the direction of the ramp.

11. Apparatus according to claim 10, wherein the ramp extends to a height of substantially 0.6 millimetres relative to the support.

12. Apparatus according to claim 10 or 11, wherein the stop is disposed at an angle of substantially 450 relative to the raised surface.

13. Apparatus according to any one of claims 7 to 12, comprising an abutment shoulder at a second end of the raised surface adapted in use to prevent an engagement element on the raised surface from moving off the raised surface in the direction of the second end thereof.

14. Apparatus according to any preceding claim, comprising a guiding rib adapted to align the instrument case relative to the support and to guide the movement of the engagement elements into engagement with their respective retaining or stressing member.

15. Apparatus according to claim 14, wherein the guiding rib is adapted to engage a portion of each of the first and second engagement elements.

16. A support for supporting an instrument case comprising two or more retaining members adapted to engage respective first engaging elements of an instrument case to retain the instrument case thereon, and at least one stressing member spaced from the retaining members and adapted to engage a second engaging element of the instrument case to provide stress between the instrument case and the support.

17. Apparatus substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

18. A sUpport for supporting an instrument case substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.