GB2133633A

GB2133633A - Cases for electrical instruments

Info

Publication number: GB2133633A
Application number: GB08300299A
Authority: GB
Inventors: Robin George Clark
Original assignee: Thorn EMI Instruments Ltd
Current assignee: Thorn EMI Instruments Ltd
Priority date: 1983-01-06
Filing date: 1983-01-06
Publication date: 1984-07-25
Also published as: GB2133633B; GB8300299D0

Abstract

A case (1) for an electrical instrument includes a front panel (2) containing a display panel (3), control knobs (4) and terminals (5). The front panel (2) supports handles (6, 7) to permit the instrument to be carried. A dust cover (8) is also provided. The sides, such as (9a) and (9b), are formed from a single folded sheet and two opposing sides are formed with flanges to secure the sides to the front panel (20). The base (10) is formed with protrusions (11) to allow stacking and is secured to the front panel (2) by bolts engaged in corner pillars to provide a rigid assembly, thereby enabling heavy components to be fixed to both the front panel (2) and the base (10). <IMAGE>

Description

SPECIFICATION Cases for Electrical Instruments The present invention relates to cases for electrical instruments, such as measuring or logging instruments, and is particularly concerned with cases for such instruments as may be required to fulfil the dual purpose of being rack mounting or free standing. In the rack-mounting mode, the instrument may form part of a complex instrumentation package, whereas, in its free standing mode, the instrument may be portable (by one or more persons) or movable on wheels to permit data to be measured and/or information relating thereto to be displayed at a chosen location.

Dual purpose cases are known which include a front panel, having one or more display panels and control knobs, terminals and the like provided thereon, and handles whereby the instrument can be carried. Hitherto, however, it has been the practice to secure the electrical components, which can include components of considerable weight, to the front panel itself and/or to a strong sub-chassis which is heavy in itself and which is rigidly secured to the front panel. The components are usually protected, when the instrument is used in its free-standing mode, by means of a cover which is relatively flimsy and which is usually discarded when the instrument is to be rack-mounted. Thus it will be appreciated that the strength of the front panel and the sub-chassis must be sufficient to support all of the components of the instrument without any assistance from the cover.

In accordance with the present invention, the cover is formed so as to permit the components of the instrument to be supported by the front panel and the cover in co-operation so as to obviate the need for a rigid sub-assembly. The cover, of course, remains in place when the instrument is to be rack-mounted.

In a preferred embodiment, the cover comprises a two-part construction consisting of a folded sheet part, forming the four sides, this sheet having portions of two different heights so as to permit the formation, by bending or stamping, of flanges along two of the sides to permit attachment to the front panel. The base is preferably constructed by resin sand-casting or die-casting and is formed with rounded corners and shaped protrusions and/or recesses to permit stacking.

In order that the invention may be clearly understood and readily carried into effect, one embodiment thereof will now be described, by way of example only, with reference to the accompanying drawing, the single figure of which shows, in perspective view, a a case in accordance with one example of the invention.

Referring now to the drawing, an instrument case shown generally at 1 includes a front panel 2 which contains a display panel 3, control knobs and switches, generally shown at 4 and terminals, generally shown at 5, through which suitable connections may be made to appropriate locations which contain devices whose performance is to be monitored and/ or logged. It will be understood that the layout of display panels, control knobs, switches, terminals, etc. may take any convenient form and has no bearing on the scope of this invention. The front cover 2 supports a pair of handles 6, 7 which permit the instrument to be carried or otherwise moved and also provide some protection forthe control knobs, etc. on the front panel.A clear, clip-on, vacuum formed dust cover 8 may also be provided and this cover 8 can advantageously be moulded to provide hand grips and storage compartments for leads, probes and other accessories which might otherwise need to be carried loose.

The sides, such as 9a and 9b ofthe case are formed from a single folded sheet, and two opposing sides, 9b and its opposite partner, not shown, are formed with flanges as described earlier to enable the sidesto be secured to the front panel-2.

The base 10 of the cover is cast and formed with protrusions such as 11 to allow stacking. The base is formed with rounded corners, as are the sides, to provide good strength with little weight and to cope with the strains associated with two#person manhandling.

The base 10 is secured to thefront panel 2 by means of bolts engaged in corner pillars such as 11 to provide a rigid assembly and heavy components are fixed both to the front panel 2 and to the base 10. If desired, and if the aforementioned having components are of sufficient strength and rigidity, the bolts securing the front panel 2 to the base 10 can be omitted and the two members secured together via the said components.

It is advantageous to provide a buffer member (not shown) of resilient material, such as rubber, around the perimeter of the front panel 2 when the instrument is being used in its free-standing (portable) mode. This bumper can conveniently be formed internally with slots to engage with the flanges formed at the junction ofthe sides such as 9b with the front panel 2.

It will be appreciated that the cover (four sides and base) need not be formed in two parts, but can, if desired, be made of unitary construction, for example by deep drawing techniques. It will also be appreciated that different methods to those described hereinbefore of relatively securing the front panel 2 and the base 10 may be employed if desired.

Claims

1. A case for an electrical instrument including cover means, for enclosing components of said instrument, consisting of a base portion and a plurality of wall portions upstanding from said base portion, and a panel member attached to said cover means so as to complete substantially the enclosure of said components, said cover means being formed so as to permit said components to be supported by said panel member and said cover means, in cooperation.

2. A case as claimed in Claim 1 wherein said cover means comprises a folded sheet part forming said wall portions, opposing wall portions being formed with flanges to permit attachment of said wall portions to said panel member.

3. A case as claimed in Claim 1 or 2 wherein said base portion is constructed by resin sand-casting or die-casting.

4. A case as claimed in Claim 1,2 or3 wherein said base portion is formed with rounded corners.

5. A case as claimed in any preceding claim wherein said base portion is formed with shaped protrusions and/or recesses to permit stacking os said case.

6. A case as claimed in any preceding claim wherein said panel member is attached to said cover means by fixing members engaged in pillars formed in said base portion.

7. A case as claimed in any of Claims 1 to 5 wherein said panel member is attached to said cover means via said components of said instrument.

8. A case as claimed in any preceding claim wherein said panel member contains display and/or control means associated with said instrument.

9. A case as claimed in any preceding claim wherein said panel member supports first and second handle portions for enabling the case to be manually transported.

10. A case as claimed in any preceding claim and including a dust cover to protect the exterior surface of said panel member.

11. A case as claimed in Claim 10 wherein said dust cover is moulded to provide hand grips and/or storage compartments for accessories of said instrument.

12. A case as claimed in any preceding claim and including a buffer member formed from a resilient material provided around the perimeter of the panel member.

13. A case substantially as herein described with reference to the accompanying drawings.