GB2212879A

GB2212879A - Corner piece

Info

Publication number: GB2212879A
Application number: GB8727560A
Authority: GB
Inventors: Johnathan Harry Townsend
Original assignee: CIRRUS ELECTRICAL ENGINEERS LI
Current assignee: CIRRUS ELECTRICAL ENGINEERS LI
Priority date: 1987-11-25
Filing date: 1987-11-25
Publication date: 1989-08-02
Anticipated expiration: 2007-11-25
Also published as: GB8727560D0; GB2212879B

Abstract

A corner piece (2) for connecting frame members (40) has a body of cubic configuration with three adjacent faces having resilient integral flanges for engagement within the frame members. Apertures are provided to abut bolt heads (42, 48), the arrangement being such that a bolt stem (46) of a bolt abutting one of the faces can pass over the top of the heads of the bolts abutting two of the other faces. <IMAGE>

Description

TITLE: Corner Piece DESCRIPTION: The invention relates to corner pieces for use at the corners of metal frame which may be pre-fabricated in factories or assembled on site for use especially in electrical equipment housings.

It is common practice to assembly a structural framework from tubular metal joined at right angles at the corners along X, Y and Z axes by corner pieces. Different fastening principles have been used: welding; bolting from the frame members into the corner pieces; and bolting sideways through the frame members into long spigots of the corner pieces.

All established methods suffer from one or more of the following disadvantages. Parts may have to be accurately machined to ensure a good fit which deters the use of pre-painted components and on-site assembly; lengthy assembly procedures; extra finishing operations after assembly; the use of special, expensive fasteners and the need for large stock range if orders are to be met at short notice.

The invention aims to provide an improved corner piece and an improved overall frame assembly.

The invention provides a corner piece for a frame including an integrally formed body having a substantially cubic configuration in which a plurality of individual projections are provided, resiliently movable individually on three first adjacent faces for locating side frame members and apertures for bolts on the remaining three second adjacent faces, two of such apertures being adapted to pass a bolt head and being opposite first shoulders formed on two of the first adjacent faces for abutting the bolt heads and one such aperture being adapted to provide a second shoulder for abutting a bolt head, the arrangement being such that a bolt stem of a bolt abutting one of the second adjacent faces can pass over the top of the heads of the bolts abutting at the first adjacent faces to enable the frame members received on the projections to be engaged by the bolts.

The projections may be flanges which can be kept short and compact and slide smoothly into the ends of the frame members, with the flanges moving resiliently only to the small extent necessary to allow for variations in size due to manufacturing tolerances. After frame assembly, the bolt heads (preferably cap head) on the first shoulders can be secured to pull the frame members firmly into position after which the bolt for abutting the second shoulders can be secured.

It is surprising that such a complex arrangement of bolts whose X, Y and Z axes intersect internally of the body, can be accomodated using bolts with the same standard thread.

Preferably the body of stainless steel, cast or moulded.

The corner piece may be finished before assembly by polishing, coating (i.e. painting).

Suitably a pair of flanges is provided on each of the first adjacent faces or even a flange is provided on all side of each of the first adjacent faces. No part of the flanges extends hence to the internal corners of the frame end, ensuring that the frame member and corner piece can be readily combined without fouling one another.

Advantageously a pair of the first adjacent faces are formed by walls contiguous with walls for the three second adjacent faces which walls have each the individual flanges thereon and a central hole for forming the first shoulders and the respective walls have a thickness exceeding that of the flanges so as to provide locating shoulders for tubular frame members located on the respective flanges, and the third of the first adjacent faces has a large central recess for defining a cavity internally of the body for passing the respective bolt heads and stems. Distortion after casting can be minimised, firm shoulders can be formed to resist the bolting forces, flanges can be sufficiently thin for the resilience appropriate to the application, and squared of ends of the frame members can be located to provide a visually continuous exterior surface after assembly.

The frame to be made preferably includes at least one corner piece having adjacent a frame member with, adjacent the corner piece, an internal insert spot-welded to the frame member for engaging the bolts and the frame is of pre-finished components with caps sprung into the apertures in the second adjacent faces.

DRAWINGS: Figure 1 is a perspective view of a corner piece of the invention; Figures 2, 3, 4, 5 are different elevations and Figure 6 is a section along line A-A of Figure 2 of the corner piece of Figure 1; and Figure 7 shows a part of a frame. partly in dashed lines, incorporating the corner piece of Figure 1.

With reference to the Figures, a body 2 is of cubic configuration with five faces 4, 6, s, lo, 12 formed concretely by cast walls of the stainless steel material of which the body is made and one imaginary face 14. Three sets of four flanges 20 are formed on the sides of three adjacent faces lo, 12 and 14, the flanges being mutually separated, individially springable to a small degree, being clear of the corners and thinner wall thickness than other parts of the body 2. Referring to Figures 2 to 6 in particular, the adjacent faces 4, 6, 8 form apertures 24, 26, 28 for bolts, two of which (24, 26) are sufficiently wide to allow the bolt heads to pass through and one of which (28) is recessed and forms a shoulder 30 for engaging the respective bolt head.Two adjacent faces 10, 12 form apertures with shoulders 32, 34 for the bolt heads which have passed through apertures 24, 26.

When being formed, a central casting part forms a cavity 36 internally of the body 2 arranged to provide a wall thickness exceeding the flange thickness, preferably two times the flange thickness but with the face 8 with the bolt head recess thicker to provide sufficient recess depth. Locating shoulders 38 for individual frame members (40) can thus be provided.

With reference to Figure 7, the cavity 36 and body 2 provide just sufficient space and access for permitting a pair of bolt heads 42 of bolts 44 to be secured internally of the cavity 36 just clear of one another, after which the final bolt 46 can be secured by the shoulder 30 engaging bolt head 48 in the aperture 28 to complete assembly.

Plastic covers may be clipped onto the body to provide a good exterior appearance.

Claims

CLAIMS:

1. A corner piece for a frame including an integrally formed body having a substantially cubic configuration in which a plurality of individual projections are provided.

resiliently movable individually on three first adjacent faces for locating inside frame members and apertures for bolts on the remaining three second adjacent faces, two of such apertures being adapted to pass a bolt head and being opposite first shoulders formed on two of the first adjacent faces for abutting the bolt heads and one such aperture being adapted to provide a second shoulder for abutting a bolt head, the arrangement being such that a bolt stem of a bolt abutting one of the second adjacent faces can pass over the the heads of the bolts abutting at the first adjacent faces to enable the frame members received on the projections to be engaged by the bolts.

2. A corner piece according to claim 1 in which the body of stainless steel, cast or moulded.

3. A corner piece according to any of the preceding claims in which the projections include a pair of flanges provided on each of the first adjacent faces.

4. A corner piece according to claim 3 in which a flange is provided on all sides of each of the first adjacent faces

5. A corner piece according to claim 3 or claim 4 in which a pair of the first adjacent faces are formed by walls contiguous with walls for the three second adjacent faces which walls have each the individual flanges thereon and a central hole for forming the first shoulders.

6. A corner piece according to claim 5 in which the respective walls have a thickness exceeding that of the flanges so as to provide locating shoulders for tubular frame members located on the respective flanges, and the third of the first adjacent faces has a large central recess for defining a cavity internally of the body for passing the respective bolt heads and stems.

7. A frame including at least one corner piece according to any of the preceding claims having adjacent a frame member withy adjacent the corner pieces an internal insert spot-welded to the frame member for engaging the bolts.

8. A frame according to claim 7 made of pre-finished components and having caps sprung into the apertures in the second adjacent faces.