GB2064053A - Resilient corner connector - Google Patents

Abstract

Each arm of an L-shaped corner connector for tubular frame members 4, 6 includes a portion of channel section with the spacing between the free edges of sides 13, 15 of the channel being greater than the internal width of the tubular frame and the side 15 is resiliently deformable, so that, on insertion, the sides 13, 15 are resiliently urged against the internal side walls of the frame member. Each arm also has a resilient catch 10, 11 for engaging in a hole 18 in the frame member. <IMAGE>

Description

SPECIFICATION Spring clip The present invention relates to a spring clip for use in an angle joint between two frame members having recessed end portions, for example, in a picture frame.

In such frames there arises the problem of firmly holding the frame members together so that they cannot move relative to each other either within or out of the plane of the frame members and cannot become unintentionally separated.

It is an object of the present invention to provide a spring clip which minimises such problems in a simple and economical manner.

The present invention provides a spring clip for use in an angle joint between two frame members each having a recessed end portion having opposed internal side walls extending through the principal plane of the joint at a predetermined spacing from each other, said spring clip comprising a first arm and a second arm each having an inboard end and an outboard end, said arms extending from each other at a predetermined angle, each said arm having a first resiliently deformable abutment means on one side of the arm, said abutment means having a first outwardly disposed abutment surface extending substantially parallel to a second abutment surface on the opposite side of the arm at a predetermined spacing therefrom slightly larger than said predetermined spacing between said internal side walls of the respective frame member end portion so that said arm may only be accommodated within said end portion, in use of the clip, with said abutment means resiliently deformed to urge said first and second abutment surfaces firmly against said opposed internal side walls, each said arm also having a resiliently deformable retainer means formed for engagement with co-operating means provided at an internal wall of a respective one of said recessed frame end portions in a fully inserted position of said arm therein, in use of the clip, for retaining said arm in said fully inserted position in said recessed end portion.

In one aspect the present invention provides a spring clip for use in an angle joint between two frame members having recessed end portions, said spring clip comprising a first arm and a second arm each having an inboard end and an outboard end and extending from each other at a predetermined angle, each said arm having a first resiliently deformable abutment means on one side of the arm said abutment means having an abutment surface extending substantially parallel to an abutment surface on the other side of the arm, said abutment surfaces resiliently engaging opposite sides of the recessed frame member end portions in use of the spring clip, and each said arm having a resiliently deformable retainer means formed for engagement with cooperating means provided at an internal face of a respective one of said recessed frame end portions, in use of the spring clip, for retaining said arm in said recessed end portion.

An advantage offered by the present invention is that in a joint made using the spring clip of the invention the frame members are firmly held so as to prevent unintentional separation and so that the angle between them is maintained at a substantially constant value.

Advantageously also the arms and preferably also at least one of the retainer and abutment means are made of height corresponding closely to the internal height of the recessed frame end portions so that the arms are a close fit in the recessed end portions in a direction out of the principal plane of the spring clip so that distortion of the joint out of the plane of the frame members is also substantially prevented.

Further features and advantages of the invention will appear from the following description of one specific embodiment illustrated with reference to the accompanying drawings in which: Figure lisa perspective view of a partially assembled joint using a spring clip of the invention; and Figure 2 is a plan view of the spring clip of Figure 1.

In Figure 1 is shown a spring clip 1 having a first arm 2 about to be inserted into the recessed end portion 3 of a first frame member 4, the second arm 5 having been already inserted into the recessed end portion 3 of a second frame member 6.

As may be seen in Figure 2 the first and second arms 2, 5 extend from each other at right angles, this particular clip being suitable for joining frame members at right angles -- e.g. as in a conventional picture frame.

Each arm 2, 5 has an inboard end 7 and an outboard end 8 and is essentially in the form of an upright - (i.e. extending vertically upwards from the principal plane of the clip) strip of resilient material such as spring steel, the outboard end 8 of which strip is turned 9 first inwardly at approximately 450 towards the other arm and then 10 again inwardly upon itself at about 450 to provide a retainer 11.

A generally L-shaped portion 12 disposed in the principal plane of the clip 1 is connected along each of its two outer side edges 13 to a respective one of said arms 2, 5 and at each of its inward side edges 14 is provided with an upturned portion 1 5 which extends parallel to the respective arm 2, 5. The two arms of the L-shaped portion 12 provide abutment means, the outermost side edge of the upturned portion 1 5 constituting an abutment surface 1 6 which extends parallel to the outermost side of the strip constituting the arm 2, 5 which side constitutes a further abutment surface 17.

The upturned portion 1 5 extends upwardly and outwardly at an acute angle to the vertical (i.e. to the plane of the strip constituting the arms 2, 5) of, for example, about 450 so that it can be resiliently bent towards the arm 2, 5 when lateral pressure is applied to its abutment surface 1 6. In this connection it may be noted that whilst a greater contact area between the clip at this point and the frame member may contribute to greater positional stability the abutment surface may in practice provide no more than a line contact in some cases and the expression "abutment surface" is to be construed accordingly.

The spring clip 1 is made with certain predetermined dimensions as follows: (1) The spacing of the abutment surfaces 1 6 and 17 7 is made slightly greater than the internal width of the respective recessed frame end portions 3 so that upon insertion of the arm 2 or 5 into said recessed frame end portion the upturned portion 15 is bent back and the abutment surfaces resiliently compressed to give a firm lateral fitting.

Naturally in each case the stability of the fitting will depend on the strength of the resiliently deformable abutment means, i.e. the force required to produce a given displacement and the actual displacement force involved -- which will in turn depend on the difference between the internal width and the spacing of the abutment surfaces. Both of these factors can readily be varied by suitable choice of material, thickness of material, relative dimensioning and other appropriate factors all within the knowledge of the ordinary person skilled in the art.

(2) As may be seen from the drawings the retainer 11 functions by engagement of the inwardly facing corner formed at the point 10 at which the end portion of the strip constituting the retainer 11 with an aperture 1 8 extending through the wall of the frame member 4 from the recessed end portion 3, both the corner 10 and aperture being at corresponding predetermined distances from the corner of the clip and joint respectively so that when the joint is assembled the frame members are held closely together at the corner.

Although in this case the co-operating means are constituted by an aperture, other forms are also possible, e.g. a recess in or a raised portion on the internal wall of the recessed frame end portion 3.

Also the retainer and co-operating means could be positioned on the outside rather than on the inside of the corner.

(3) The strip constituting the arms and the retainers has a predetermined height closely corresponding to the internal height of the recessed frame member end portion 3, desirably so as to provide a sliding push fit, to substantially prevent movement of the frame members out of the principal plane of the clip.

Although in the example described both arms have substantially identical dimensions it is of course possible for them to have different dimensions where it is desired to join frame members with unequal dimensions.

Conveniently the clip is made by cutting or stamping out from a sheet of spring steel or other suitable material a generally L-shaped blank and then bending up strip portions to provide the arms 2, 5, the ends of the strip portions being bent round to provide the retainers 11 and bending up edge portions to form the upturned edges 14 providing the abutment surfaces 1 6. It will be noted that in this embodiment the arms are connected to each other only by the L-shaped portion providing the abutment means. It will of course be appreciated that other constructions are possible in which the arms are directly connected at the corner of the spring clip and optionaily the respective abutment means are separate from each other. The use of such a L-shaped portion does however increase the stability of the joint in the principal plane thereof.

In a further aspect the present invention provides a blank for use in forming a spring clip of the invention and in particular a blank for use in forming a spring clip substantially as described hereinbefore.

In another aspect the present invention provides a frame, for example, a picture frame, having at least two frame members with recessed end portions and joined together at an angle to one another to form a corner of the frame by a spring clip of the invention, said recessed end portions having co-operating means arranged for engagement with the retainer means of the spring clip, each arm of the spring clip being inserted into the recessed end portion of a respective frame member.

Claims (14)

1. A spring clip for use in an angle joint between two frame members each having a recessed end portion having opposed internal side walls extending through the principal plane of the joint at a predetermined spacing from each other, said spring clip comprising a first arm and a second arm each having an inboard end and an outboard end, said arms extending from each other at a predetermined angle, each said arm having a first resiliently deformable abutment means on one side of the arm, said abutment means having a first outwardly disposed abutment surface extending substantially parallel to a second abutment surface on the opposite side of the arm at a predetermined spacing therefrom slightly larger than said predetermined spacing between said internal side walls of the respective frame member end portion so that said arm may be accommodated within said end portion, in use of the clip, with said abutment means resiliently deformed to urge said first and second abutment surfaces firmly against said opposed internal side walls, each said arm also having a resiliently deformable retainer means formed for engagement with co-operating means provided at an internal wall of a respective one of said recessed frame end portions in a fully inserted position of said arm therein, in use of the clip, for retaining said arm in said fully inserted position in said recessed end portion.

2. A clip as claimed in claim 1 wherein each said arm has a web portion in or parallel to a principal plane of the clip, and each said first abutment means is in the form of a free upturned edge portion extending along one side of the respective web portion extending along one side of the respective web portion.

3. A clip as claimed in claim 1 or claim 2 wherein is provided a said retainer means in the form of a ratchet tooth member disposed for facilitating insertion into and resisting withdrawal from a respective recessed frame end portion of a respective said arm.

4. A clip as claimed in claim 3 wherein said ratchet tooth member is in the form of a leaf spring connected at one end to a respective arm, having a first portion extending from said arm at an acute angle thereto and a second portion cranked back towards said arm to provide a stop surface extending at a steeper angle to said arm, said first portion having an extent in a direction perpendicular to said arm slightly greater than the corresponding internal dimension of the respective recessed frame end portion.

5. A clip as claimed in claim 4 wherein said leaf spring is formed integrally with the respective arm.

6. A clip as claimed in claim 5 wherein each arm has an elongate strip portion of a resiliently deformable material disposed in a plane substantially at right angles to the principal plane of the clip and said leaf spring forms an extension of said strip portion.

7. A clip as claimed in any one of claims 1 to 6 wherein is provided a said retainer means in the form of a catch member biased outwardly of the respective arm into a retaining position.

8. A clip as claimed in any one of claims 1 to 7 wherein each of said arms has a planar portion formed integrally with the planar portion of the other arm and extending in a single plane coincident with a parallel to a principal plane of the clip.

9. A clip as claimed in any one of claims 1 to 8 which clip is generally L-shaped.

10. A clip as claimed in any one of the preceding claims which is formed in a single piece from a sheet of a generally rigid resiliently deformable material.

11. A clip as claimed in claim 10 wherein said material is spring steel.

12. A spring clip for use in an angle jointbetween two frame members having recessed end portions, said spring clip comprising a first arm and a second arm each having an inboard end and an outboard end extending from each other at a predetermined angle, each said arm having a first resiliently deformable abutment means on one side of the arm said abutment means having an abutment surface extending substantially parallel to an abutment surface on the other side of the arm, said abutment surfaces resiliently engaging opposite sides of the recessed frame member end portions in use of the spring clip, and each said arm having a resiliently deformable retainer means formed for engagement with co-operating means provided at an internal face of a respective one of said recessed frame end portions, in use of the spring clip, for retaining said arm in said recessed end portion.

13. A spring clip for use in an angle joint substantially as described hereinbefore with particular reference to the accompanying drawings.

14. A frame having at least two frame members with recessed end portions and joined together at an angle to one another to form a corner of the frame by a spring clip according to any one of the preceding claims, said recessed end portions having co-operating means arranged for engagement with the retainer means of the spring clip, each arm of the spring clip being inserted into the recessed end portion of a respective frame member.