GB2043196A

GB2043196A - Cable connector

Info

Publication number: GB2043196A
Application number: GB8002029A
Authority: GB
Original assignee: Bowden Controls Ltd
Current assignee: Bowden Controls Ltd
Priority date: 1979-01-24
Filing date: 1980-01-22
Publication date: 1980-10-01
Also published as: FR2447489A1; DE3002081A1

Abstract

A connector device for connecting two lengths of cable, wire or rod comprises two end components (12, 13) secured to the two lengths to be joined, which end components have co- operating inclined faces (18), and a sleeve (20) for holding the two components together so that tension applied through the joint causes the end components (12, 13) to be forced outwardly by wedge action against the said sleeve. <IMAGE>

Description

SPECIFICATION Cable connector This invention relates to a connector device suitable for connecting two tie member such as wires or cables in end to end alignment so that tensile forces can be transmitted through the joint.

For endwise connecting wires or cables it is known to provide the ends of the wires or cables with coupling components of inter-engageable hook form and to provide retaining means which is locatabie around the said coupling components to retain them in engagement with each other.Theretaining means comprises two tubes and a coupling or locking ring which holds such tubes coupled end to end around the coupling components.

It is an object of the present invention to provide a connector device which as compared with the prior art devices makes better use of the material strength.

of the components employed.

The present invention provides a connector device which significantly departs from the known practice by making use of an inclined plane or wedge principle which causes the retaining means to participate in the load transmission.

According to the present invention there is provided a connector device suitable for connecting two tie members in end to end alignment so that tensile forces can be transmitted through the joint, said device comprising a pair of components (hereafter calledend components) which are or can be attached to two said tie members and which have portions shaped for mutual engagement in overlapping load-transmitting relationship, and retaining means for positioning around such components to retain them on such relationship, characterised in that said end components are shaped so that under tensile forces through the joint, mutually contacting faces of said components co-operate with an in dined plane effect whereby said components are mutually forced outwardly against said retaining means.

The invention affords a combination of advantages. The retainer serves not only a retaining function but also co-operates with the end components in transmitting tensile forces through the joint.

And because of the manner in which the end components co-operate with each other and with the retaining means when the joint is loaded, the end components can be shaped to achieve a more efficient use of the material thereof than would be possible if the end components were to be formed for hooking one into the other. When making coupling components of inter-engageable hook form each component is shaped with a recess or groove for receiving the hook portion of the other component and if the components in their coupled condition are to be co-axial this entails appreciable local reduction of the cross-section of the components.

Each end component of a device according to the present invention can be swaged or otherwise secured to an end portion of one of two tie members to be connected. The tie members may, e.g. be cables or rods.

The invention includes connector devices as hereinbefore defined wherein the angles between the inclined plane and the surfaces of contact between said end components and the retaining means are such that said end components can be friction-locked against said retaining means by Ibading the joint in tension. In general terms this means that under first application of a sufficient tensile load, the end components behave as self-locking wedges. Each of them becomes friction-locked be-tween the other ofthem and the retaining means and a compression load has to be applied, causing a relative axial approach movementofthe end components, in orderthatthe retaining means can be freed for axial movement preparatry to uncoupling the tie members.It is a simple matter to select the inclined plane angle relative to the angles of friction between the contacting parts of the device s6asto achieve the self-locking wedge effect.

Devices according to the invention and embodying the sel'f-locking wedge feature afford exceptional advantages. Once friction-locking has occurred in response to sufficient tensile loading of the coupling, the end components and retaining means act as a unitary structure. On relaxation of axial tension the end components remain held against relative axial movement and the coupling can be used for repetitive transmission oftensile loads without"chattering of the end components such as occurs in the case of hook-type couplings in which it is essential for clearance to be present between the inter-engaging hook components to permit them to be easiiy coupled and uncoupled.The behaviour of the end components and the retaining means as a unitary structure is of particular importance in certain uses of the connector device, e.g. in order to avoid lost motion in the case that the device is used for coupling tie members which extend between anactuating and an actuated member.

Preferably the mutually co-operating faces of the end components are flat faces which are in parallel planes when such components are in overlapping load-transmitting relationship within the retaining means. As an alternative, one of such faces may be flat and the other may be convexly curved towards' that flat face. However co-operation between two flat parallel faces for achieving the inclined plane effect is much more satisfactory in terms of efficient load distribution. It is advantageous, for the same object of efficient load distribution, for the end components to be shaped so that when they are in working position within the retaining means they have a common axis of symmetry in the direction in which tensile forces are transmitted through the joint and so that said flat faces are symmetrical relative to that common axis.

The outward pressures exerted on the retaining means when tensile forces are transmitted can assist in holding the retaining means in position and the invention permits a considerable scope in the choice of the retaining means design.

Preferably the retaining means is a one-piece component in the form of a sleeve. Advantageo-usly the retaining means is a sleeve which is of a length sufficient to envelop the end components in their overlapping load-transmitting relationship and which is held in operative position, against inadvertent axial displacement, solely by engagement with the end components.

If the end components behave as self-locking wedges as above described, the retaining means can be in the form of a sleeve which is retained in operative position merely by the outward forces exerted against it by the end components. In an alternative construction the retaining means comprises a sleeve having end portions which in the operative condition of the device project inwardly over end faces of the end components to obstruct relative axial recession of such end components.

This construction is suitable regardless of whether or not the end components behave as self-locking wedges. In one example, one end portion of the sleeve comprises a fixed radially inwardly projecting flange and the other end portion of the sleeve comprises one or more radially displaceable lugs.

Such lug(s) can be radially inwardly displaceable by deformation of the sleeve material or such lug(s) may have a spring characteristic and be set so as to move automatically into locking position under elastic recovery forces as the sleeve is displaced into its correct use position.

The invention is very suitable for joining wires or cables of mechanical remote control mechanisms, e.g. wires or cables constituting the inner member of a Bowden-type mechanism constituting the inner members of a pair of such mechanisms. When fitting a Bowden-type control mechanism in certain machines, e.g. for brake-control purposes in auto mobiles, it is sometimes convenient for part of the inner member of such a control mechanism to be secured to a machine sub-assembly prior to attach ment of the remainder of the control mechanism. In such circumstances the part of the inner member secured to the sub-assembly can be very conve niently connected to the remainder of the inner member by means of a cable connector device according to the invention.

Reference is now made to the accompanying diagrammatic drawings in which: Figure 1 is a part-sectional elevation of a prior art connector device; Figure 2 is a perspective view showing two stranded wire cables fitted with end components of a connector device according to the present invention and showing the retainer ready for sliding into position; and Figure 3 is a part-sectional elevation of that connector device in use.

The known connector device shown in Figure 1 comprises two coupling components 1 and 2 of hook form and retaining means which comprises a pair of tubes 3,4 and a coupling or locking ring 5 which in this example is rotatably mounted on tube 4 and makes screw threaded engagement with tube 3. The tubes are connected to casings 6 and 7 of two tie members 8 and 9 to which the coupling components 1 and 2 are secured. Tensile loads are transmitted directly through the abutting faces 10, 11 of the hook components.

The connector device shown in Figures 2 and 3, which is constructed in accordance with the present invention, comprises two metal end components 12 and 13 machined from mild steel. The two end components are identical. Referring to component 12, it has an inner end portion 14 with a bore whichreceives an end portion of a cable 15, a medial portion 16 of larger cross-section, and a wedgeshaped outer-end portion 17 whose inclined face 18 lies at an angle of 17" to the longitudinal axis of the component, which coincides with the line along which tensile forces are transmitted through the connector when it is in use. The inner end portion 14 is swaged onto the cable 15. End component 13 is likewise swaged onto cable 19.

The connector is used by placing the two wedgeshaped outer end portions of the end components together with their inclined faces in contact and then sliding a metal sleeve 20 into position around the two components. At one end the sleeve has a fixed radially inwardly projecting flange 21 which abuts against the radial face 22 at one end of the medial portion of component 13. At the opposite end portion of the sleeve there are opposed axial slots such as 23. Once the sleeve has been moved into a position in which it abuts face 22 of component i3 is above described, the lugs or tongue portions 24,25 separated by the two slots are bent inwards behind the radial face 26 of component 12, as appears from Figure 3. The sleeve is thereby held against inadvertent displacement relative to the two end components.So long as the sleeve is in place the two end components 12, 13 are prevented from relative lateral movement (lateral with respect to the axis of the connector) and the end components therefore cannot separate under load. When the cable is placed under tension a slight relative sliding move ment of the end components is such in relation to the frictional coefficients between the different parts of the device that the device then behaves as a unitary structure during applications and relaxations of the tensile force on the cable.

The connector can be uncoupled by striking the ends 27, 28 of the two end components 12 and 13 to move them axially towards each other and release the wedge lock against the sleeve 20, and then withdrawing the sleeve from the end components.

As already indicated herein, the lugs or tongue portions 24,25 of the sleeve 20 could be pre-set in convergent positions and given appropriate elastic ity so that they have to be elastically splayed to enable the sleeve to slide over the end components but then spring inwardly into locking position behind face 26 as the sleeve moves into its correct locking position.

In an alternative construction of retainer (not shown) it is in the form of a sleeve of uniform cross-sectional dimensions and of a length just sufficient to cover the two end components 12,13 and reliance is placed on the self-locking wedge effect to hold the sleeve against inadvertent axial displacement.

Claims

1. A connector device suitable for connecting two tie members in end to end alignment so that tensile forces can be transmitted through the joint, said device comprising a pair of components (hereafter called end components) which are or can be attached to two said tie members and which have portions shaped for mutual engagement in overlapping load-transmitting relationship, and retaining means for positioning around such components to retain them in such relationship, characterized in that said end components co-operate with an inclined plane effect whereby said components are mutually forced outwardly against said retaining means.

2. A connector device according to claim 1, wherein the angles between the inclined plane and the surfaces of contact between said end components and said retainer are such that said end components can be friction-locked against said retainer by loading the joint in tension.

3. A connector device according to claim 1 or 2, wherein the mutually contacting faces of the end components are flat faces which are in parallel planes when the components are in overlapping load-transmitting relationship within the retainer.

4. A connector device according to claim 3, wherein said end components are shaped so that when they are in working position within the retainer they have a common axis of symmetry in the direction in which tensile forces are transmitted through the joint and so that said flat faces are symmetrical relative to that common axis.

5. A connector device according to any preceding claim, wherein the retaining means is a onepiece component in the form of a sleeve.

6. A connector device according to claim 5, wherein the sleeve is of a length sufficient to envelop the end components in their overlapping loadtransmitting relationship and which is held in operative position, against inadvertent axial displacement, solely by engagement with the end components.

7. A connector device according to claim 2 and any of claims 3 to 6, wherein the retaining means is in the form of a sleeve of uniform cross-sectional size which is retainable in operative position merely by the outward forces exerted against it by the end components.

8. A connector device according to any of claims 1 to 6, wherein the retaining means comprises a sleeve having end portions which in the operative condition of the device project inwardly over end faces of the end components to obstruct relative axial recession of such end components.

9. A connector device according to claim 8, wherein one end portion of the sleeve has one or more radially displaceable lugs for projecting inwardly over an end face of one of said end components.

10. A connector device according to any preceding claim, the said end components of such device being connected to wires or cables constituting the inner member of a Bowden-type mechanism or constituting the inner members of a pair of mechanisms.

11. A connector device substantially as herein described with reference to and as illustrated in Figures 2 and 3 of the accompanying diagrammatic drawings.