GB2034186A

GB2034186A - Adjustable coupling

Info

Publication number: GB2034186A
Application number: GB7845473A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-11-21
Filing date: 1978-11-21
Publication date: 1980-06-04

Abstract

A coupling for effecting releasable interconnection between two or more members (not shown) comprises two hemispherical shells 1, 2 releasably connected together, preferably by a bolt 6, to form a sphere, each shell having one or more slots 3, 4 within which a hollow connection piece 5 is adjustably secured. A member to be joined is received in sliding fit in the free end (9, figure 3, not shown) of the connection piece 5, which may include a support sleeve (12) to receive a bolt 13 which co-operates with a nut 14 within the sphere to secure the connection piece in position. <IMAGE>

Description

SPECIFICATION An improved coupling The present invention concerns a coupling for effecting a releasable connection between two or more members.

It is frequently required to effect a connection between two or more adjacent separate members and, as example only, reference can be made to toy or model constructional kits having a pluraiity of elongate members which are to be joined together to form a variety of different shapes and designs. The present invention provides a coupling for achieving such a connection.

According to the present invention a coupling comprises first and second portions having circular end faces, means for releasably connecting the portions together with their circular end faces in parallel relationship and at least one connection piece adjustably mounted on each portion for releasably receiving an end of a member to be connected by the coupling.

Preferably, the first and second portions of the coupling comprise hemi-spherical shells and conveniently each shell carries two connection pieces. Each connection piece can be slidable in a slot in the shell and can be adjustably secured at any desired position along the length- of the slot.

The invention will be described further, by way of example, with reference to the accompanying.

drawings; in which: Fig. 1 is a sectional view of a coupling, according to the invention, comprising two cojoined slotted hemispherical shells with a connection piece for receiving a member to be connected to the coupling mounted on one of the shells; Fig. 2 is a view of the hemispherical shells and omitting the connection piece.

Fig. 3 is a sectional view of the connection piece; Fig. 4 is an end view of the connection piece in the direction of arrow in Fig. 3.

The illustrated coupling comprises a hollow sphere formed from two hemi-spherical shells 1 and 2 which are releasably connected together and rotatable the one relative to the other. The hemi-spherical shells are each formed with two elongate slots 3 and 4 respectively and a connection piece 5 is mounted in each slot. Only one such connection piece 5 is shown in Fig. 1 but in practice a similar connection piece will be mounted one in each of the three remaining slots.

The two hemi-spherical shells 1 and 2 are secured together by a bolt 6. Diametrically opposite portions of the two shells are reinforced or enlarged to receive the opposite ends of the bolt. The head of the bolt 6 is received within a countersunk bore in the shell 2 and the opposite threaded end of the bolt 6 cooperates with a threaded bush 7 formed as an integral part of the shell 1. The bolt head can be formed with a socket to receive a key for tightening and loosening the bolt.

The slots 3 and 4 are disposed symmetrically about the common plane of the two hemispherical portions and the angle included between any two adjacent slots is substantially 900. As seen from Fig. 2, the length of each slot is such that the slot subtends a large obtuse angle at the centre of the sphere and preferably this angle is as close to 1 800 as is practical within the limits of construction.

The connection piece 5 shown in Figs. 3 and 4 comprises a hollow stub 8 having an open end 9 to receive an end of a member (not shown) to be connected to the coupling. The opposite end 10 of the connection piece is formed with a curved surface 11 having a radius of curvature in any plane through the surface substantially equal to the radius of curvature of the shell. Consequently, the end 10 of the connection piece can fit smugly against the surface of the shell. A support sleeve 1 2 extends within the stub 8 from the end 10 and the sleeve 12 has a through aperture to receive a bolt 13 (Fig. 1). The head of the bolt 13 is formed with a socket to receive an actuating key.

Preferably, the sockets in the heads of the bolts 6 and 1 3 are identical to receive a common key.

The end of the bolt 1 3 extends through the slot in the shell and cooperates in screw thread engagement with a securing nut 14 within the shell. The surface of the nut 14 which is adapted to engage the inner surface of the shell is preferably contoured to the same curvature as the shell. The nut is further provided with means to resist rotation thereof when tightening and loosening the bolt 1 3. Such means can be guides engageable in the slot in the shell. For example, the nut can be keyed to slide along the length of the slot and to prevent rotation.

The coupling can conveniently be formed from a rigid plastics material such as polypropylene.

In use, a connection piece 5 is mounted in each of the slots in the hemi-spherical shells 1 and 2 and the two shells are joined together by the bolt 6. The relative angular positions of the shells and the position of each connection piece are adjusted such that the connection pieces extend in desired directions to conform to the orientation of the members to be joined together by the coupling. In the illustrated embodiment, such members are a push-fit in the stubs 8 of the connection pieces 5 although it is possible to provide means for positively locking the members to the stubs 8.

Thus by adjustment of the positions of the connection pieces it is possible to join together four separate members by means of the coupling.

One use of the invention is as a coupling to enable a child to construct an assembly from a plurality of individual rods or bars. A constructional kit of couplings and rods or bars can be used to build a variety of frames or structures. The ends of the individual rods or bars are pushed into the stubs of the connection pieces of the coupling and the coupling is arranged to provide the required angular orientation between the rods or bars attached to the coupling. The connection pieces and the two hemi-spherical shells of the coupling can be releasably locked in a desired, position by tightening the respective bolts 6and 13.

It will be appreciated that the coupling can be modified in a number of ways without departing from the scope of the invention. As simple - examples, it is possible to form the coupling from materials other than plastics and the sockets can have circular and not square openings to receive rods and not bars. Although it is convenient to provide the sleeve within the connection piece, and which sleeve can be separate from and not integral with the base of the connection piece, in order to locate the head of the bolt 1 3 adjacent the open end of the stub for ease of access it will be appreciated that such an arrangement is not essential. A sleeve can be omitted and a short bolt 13 or other locking means can be passed through the end 10 of the connection piece to engage the securing member.

It will be realised that the coupling is not confined for use with four connection pieces. Each hemi-spherical shell can be provided with a single connection piece or more than two connection pieces. Consider the case of the illustrated embodiment in which each shell is provided with a single connection piece with the axis of the connection piece being inclined at 450 to the circular end plane of its shell. The minimum bend that can be formed by such a coupling is 900, that is the minimum angle possible between the axes of the two connection pieces. Upon relative rotation between the circular faces of the shells the bend angle will progressibely increase from 900 until the connection pieces are in substantial axial alignment and thereafter the bend angle will progressively decrease to 900. The disposition of the members to be connected by the coupling is immaterial in this case because having achieved the required angle by relative rotation of the two hemi-spherical shells the two connection pieces can then be aligned with the members, Clearly the connection piece can be positioned on the shell to achieve a minimum bend angle less than 900.

It will be appreciated that a coupling as described herein can find a variety of uses and is not limited to use in toy or model construction kits.

Claims

1. A coupling for effecting a connection between two or more members comprising first and second portions having circular end faces, means for releasably connecting the portions together with their circular end faces in abutting relationship and at least one connection piece releasably and adjustably mounted on each portion for receiving an end of a member to be connected by the coupling.

2. A coupling according to claim 1 in which the first and second portions each comprise a hemispherical shell.

3. A coupling according to claim 1 or 2 in which each connection piece is slidable in an associated slot in the first and second portions and is adjustably secured at any desired position along the length of the slot.

4. A coupling according to any preceding claim in which each connection piece comprises a hollow stub having an open end to receive an end of a member to be connected by the coupling and an opposite end having a curvature to match the curvature of the associated shell.

5. A coupling according to claim 4 in which the stub is releasably and adjustably mounted on the shell by cooperating screw-threaded members.

6. A coupling according to claim 3 in which each slot subtends an angle approaching 1 800 at the centre of the coupling.

7. A coupling according to.any preceding claim in which each shell is formed with two slots disposed symmetrically about the common plane of the two hemispherical portions and the angle.

included between any two adjacent slots is substantially 900.

8. A coupling for effecting a connection between two or more members substantially as herein described with reference to and as illustrated in the accompanying drawings.