GB1596751A

GB1596751A - Clamping devices for electrical conductors and the like

Info

Publication number: GB1596751A
Application number: GB26877A
Authority: GB
Original assignee: PLASTIC SEALS Ltd
Current assignee: PLASTIC SEALS Ltd
Priority date: 1978-01-05
Filing date: 1978-01-05
Publication date: 1981-08-26

Description

(54) IMPROVEMENTS IN OR RELATING TO CLAMPING DEVICES FOR ELECTRICAL CONDUCTORS AND THE LIKE (71) We, PLASTIC SEALS LIMITED, a British company of Uddens Trading Estate, Nr, Wimborne, Dorset, BH21 7NL, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- The present invention relates to a device which is capable of clamping or securing an elongate elements such as an electrical conductor or cable, relative to a surface or member. Such a device will hereinafter be referred to as "a clamping or securing device of the type specified".

According to the present invention, there is provided a clamping or securing device of the type specified, which comprises first and second element-locåting portions molded from a synthetic plastics material and movable from a mutually open position, to a mutually closed position in which they define therebetween an element-receiving passage extending through the device, the first and second portions being provided with respective first and second locking means which are mutually cooperable to retain the portions in said closed position, and which are mutually adjustable to provide adjustment of the cross-sectional dimensions of the element-receiving passage by relative bodily movement between the portions when in their closed position, thereby to accommodate, grip and restrain against longitudinal movement relative to the device, elongate elements of differing cross-sectional dimensions when trapped in said passage, the first element-locating portion comprising a base formed integrally with two mutually spaced, generally parallel pillars defining, with the region of the base therebetween, a part of the elementreceiving passage, the pillars having regions extending lengthwise thereof provided, in a direction generally transverse to the element-receiving passage, with outwardly directed first locking means, the second element-locating portion comprising a closed loop having transversely inwardly directed second locking means and, in the closed position of the portions, bridging and surrounding the pillars and being bodily slidable therealong, along a generally linear path, towards the base of the first portion.

Each of the pillars may be provided with first locking elements comprising transversely outwardly proJecting ratchet-like teeth distributed along its length. The second portion is provided with second locking elements comprising transversely inwardly projecting teeth selectively resiliently cooperable with the first locking elements of the two pillars during said sliding movement to lock the second portion against separational movement thereof relative to the pillars, with a snap action, in one of a number of different adjusted positions.

The two element-locating portions may be integrally connected by a flexible hinge or strap which serves to prevent loss of one or other portion when the portions are in their open position, and to guide the portions as they are moved towards each other prior to .engagement of the second portion with the pillars.

One of the element-locating portions, for example the first portion, may be provided with means to facilitate attachment of the device to a surface or member. More particularly, the base of the first portion may be extended to one side of the pillars, in the longitudinal direction of the elementreceiving passage, to form a mounting lug or bush provided with an element-receiving aperture.

In use, the device is attached to a piece of electrical apparatus by the lug or bush. With the first and second portions of the device in their open position, an electrical cable comprising the elongate element is threaded through the aperature in the lug or bush so as to lie between the pillars of the first portion, and the second portion is then assembled to the pillars to trap the cable in the element-receiving passage. The second portion is then pressed towards the base so as to reduce the height of the passage to such an extent that the cable is gripped and pinched between the base and the second portion. The first and second locking elements resiliently cooperate during the closing movement, and allow this movement, but when the pressure producing this closing movement is removed, the locking elements positively interlock to retain the first and second portions in their adjusted closed position.

In order that the invention may be more readily understood reference will now be made to the accompanying drawings, in which: Figure 1 is a perspective view of an electrical cable clamp according to one embodiment of the invention, with the first and second element- or cable-locating portions shown in their open position; Figure 2 is a plan view of the clamp shown in Figure 1; Figure 3 is a longitudinal section on the line A-A of Figure 2; Figure 4 is a side view of the clamp shown in Figures 1 to 3; Figure 5 is a transverse section through the first element- or cable-locating portion on the line B-B of Figure 2; Figure 6 is a transverse section through the second element- or cable-locating portion on the line C-C of Figure 2; Figures 7 to 9 are views, similar to Figures 1, 2 and 4 respectively, of a second embodiment of cable clamp; Figure 10 is an underneath plan view of the clamp shown in Figures 7 to 9; Figure 11 is a plan view of part of a plate or chassis to which the clamp of Figures 7 to 10 is intended to be secured, and showing in broken lines, the clamp during assembly to the plate or chassis; Figure 12 is a view, similar to Figure 1, of a third embodiment of cable clamp; Figure 13 is a persepctive view from below of the clamp shown in Figure 12; Figures 14, 15 and 16 are views, similar to Figures 2, 3 and 4 respectively, of the clamp shown in Figures 12 and 13; and Figure 17 is a section on the line D-D of Figure 14.

The adjustable cable clamp shown in Figures 1 to 6 is primarily but not exclusively intended to be used for clamping the electrical cable or flex of a domestic table lamp. This cable clamp, which is molded from an electrically insulating, resilient synthetic plastics material, such as Nylon, acetal, resins such as "Delrin" (Registered Trade Mark), or polypropylene, comprises first and second element- or cable-locating portions. namely first and second clamp portions 1 and 2, interconnected by an integral flexible hinge, web or strap 3.

The clamp portion 1 comprises a generally flat plate-like base 4 including mounting means in the form of a lug 4a provided with mounting apertures 4b and 4c, and formed integrally with a pair of upstanding pillars 5 of generally oval cross section. The opposed inner surfaces of the pillars 5 and the intermediate region of the upper surface of the base 4 form the base and two sides of a cable-receiving passage, and are provided with ribs 6a and 6b. The outwardly directed surfaces of the pillars are each provided with first locking elements comprising a row of superimposed ratchet teeth 7. As will be apparent from Figure 5, the upwardly directed surfaces 7a of the teeth, i.e. those directed away from the base 4, are inclined downwardly towards the base from their juncture with the outer surfaces of the pillars, whilst the downwardly directed surfaces 7b i.e. those directed towards the base, extend generally normal to the planes of the outer surfaces of the pillar (although they may alternatively be undercut).

Clamp portion 2 is in the form of a short length of retangular-section tube provided with second locking elements comprising internal teeth 8 extending one along each of the opposed inner surfaces of the shorter sides 2a of the clamp portion 2. The profile of the teeth 8 is similar to that of the teeth 7 as will be apparent from a comparison of Figures 6 and 5. The distance between the tips of the teeth 8 approximates the spacing between the outer surfaces of the pillars 5 from which the teeth 7 project, and the distance between corresponding teeth 7 on opposite pillars 5 approximates the spacing between the opposed inner surfaces of the sides 2a from which the teeth 8 project. The distance between the opposed inner surfaces of the longer sides 2b of the clamp portion 2 approximates the width of the pillars 5 as viewed in Figures 3 and 4. Thus the clamp portion 2 comprises a rectangular, relatively rigid loop or hoop which will fit over the tops of, and surround, the pillars, with the longer sides 2b spanning the gap between the pillars so as to form the top of the cablereceiving passage.

In use of the cable clamp, with the clamp portions I and 2 in their open position, a cable is laid on the base 4, over the rib 6a, and passing between the pillars 5. By flexing the strap 3, the clamp portion 2 is then moved from the position shown in Figure 1, to an inverted position in which it overlies the tops of the pillars, and it is then pressed downwardly and slides down over the tops of the pillars until the inclined surfaces of the teeth 7 and 8 cammingly cooperate.

Further downward sliding movement of the clamp portion 2 causes the pillars to be resiliently flexed towards each other until the teeth 8 pass below the top pair of teeth 7 on the pillars, whereafter the pillars snap resiliently back to or towards their original position, and the clamp portion 2 is locked against upward separational movement by inter-engagement of the generally normal surfaces of the teeth 8 and top pair of teeth 7. The clamp portion 2 is pressed bodily further down the pillars 5, with the teeth 8 resiliently cooperating, with a ratchet-like snap action, with successive pairs of lower teeth 7 on the pillars 5, until the cable is securely gripped and pinched between the pillars 4 and clamp portion 2. In this closed position, the cable is bent or kinked over the rib 6b by the downward pressure of the lower edges of the longer sides 2b of the clamp portion 2 located on the opposite sides of the ribs 6b. Thus, in the longitudinal direction of the passage, the rib 6 defines with the said lower edges of the longer sides 2b, a tortuous passage for the cable through the device, which serves to restrain the cable against longitudinal movement relative to the clamp.

Due to the configuration of the pillars 5, clamp portion 2 and teeth 7 and 8, it will be apparent that the clamp portion 2, during closing movement, slides bodily down the pillars along a straight line path, with the plane of the lower edges of the clamp portion 2 remaining generally parallel to the plane of the upper surface of the base 4.

Thus, the clamping and restraining action will not be affected by sliding movement of the cable transversely of the passage, i.e.

from one pillar towards the other pillar, and vice versa.

Furthermore, due to the provision of plural pairs of ratchet teeth 7 on the pillars 5, the adjusted position of the clamp portion 2 relative to the base 4 may be positively adjusted to accommodate and clamp cables of varying cross-section dimensions, for example of different diameters. However, the cable may be readily released if required by deflecting the pillars towards each other, for example by applying manual pressure thereto, or by means of a tool, thereby releasing the interengaging teeth 7 and 8.

The clamp previously described may be secured in any appropriate manner to a piece of electrical apparatus, for example by securing means passing through one or more of the apertures 4b and 4c in the lug 4a. The clamp described is particularly suitable for use in clamping the cable of a domestic table lamp. A table lamp normally incorporates a metal tube carrying, at its upper end, the bulb holder of the lamp, the tube extending downwardly within the lamp and terminating, at its lower end, adjacent the base of the lamp. The cable from the bulb holder passes down the tube, out of the lower open end thereof, and is then flexed transversely, and emerges through a lateral aperture in the base of the lamp. The lower end of the tube is normally externally threaded to receive one or more locking nuts. The aperture 4b of the above described clamp is dimensioned to accommodate the threaded lower end of the tube, and is clamped thereto between a pair of lock nuts threaded on to the lower end, or between one lock nut and an opposed surface of the lamp. The clamp is mounted in an inverted position relative to that shown in the drawings, i.e. with the pillars projecting downwardly from the base 4, to one side of the open end of the lower open end of the tube. When the clamp is so mounted, the cable, where it emerges from the lower open end of the tube, is simply bent over so as to lie between the pillars, and the clamp portion 2 is then moved over on to the pillars, by flexing the strap 3, and is pressed along the pillars towards the base 4 as previously described. It will be appreciated that the strap 3 not only prevents the clamp portion 2 from being mislaid, but also serves to guide the clamp portion 2 during its movement from the position shown in Figure 1 to the position in which it overlies and initially cooperates with the pillars, whilst ensuring that the clamp portion 2 is applied to the pillars the right way up, with the inclined surfaces of the teeth 8 facing towards the inclined surfaces of the teeth 7.

As an alternative to mounting the clamp on a tube, for example the tube of a table lamp, it may be mounted upon a flat surface of a table lamp, or of any other electrical appliance, by means of screws, bolts or other securing means passing through the two smaller apertures 4c and/or the aperture 4b.

The device shown in Figures 7 to 11 is basically similar in construction and operation to the device described with reference to Figures 1 to 6. Therefore, only the additional feature or modifications of the second embodiment will be described hereinafter, and, where applicable, the same reference numerals will be used to denote the same components.

The device shown in Figures 7 to 11 comprises a combined cable clamp and electrically insulating bushing or grommet, i.e. a strain relief bushing, which is moulded in one piece from an electrically insulating resilient, synthetic plastics material.

The generally flat-plate like base 4 of the first clamp poriton 1 is provided, around the aperture 4b in the lug 4a, with a depending integral sleeve or bush 10. The sleeve 10 is circular around the major proportion of its periphery, but is provided with an arcuate enlargement 10a defining an upwardly directed shoulder 10b adjacent and projecting beyond the tip 4d of the lug 4a.

The circular portion of the sleeve has a diameter slightly less than that of a mounting aperture I la in a metal mounting plate, chassis or casing 11 of an electrical appliance (not shown) to which the strain-relief bushing is to be fitted, whilst the external diameter of the enlargement 10a is greater than the diameter of the mounting aperture I Ia.

The width of the enlargement IOa in a circumferential direction is less than the diameter of the aperture 1 la. The plane of the shoulder 10b is spaced below the plane of the underside of the base 4 by a distance approximating or slightly greater than the thickness of the mounting plate 11.

Adjacent the transverse rear edge 4e of the base 4, the base is provided with a depending integral circular boss 12 which overlaps, i.e. projects beyond, the edge 4e and is relieved to form an upwardly facing shoulder 12a. The plane of the shoulder 12a, like that of the shoulder 10b, is spaced below the plane of the underside of the base 4 by a distance approximating or slightly greater than the thickness of the mounting plate 11. The boss 12 is, in this embodiment, located approximately on the centre line of the aperture 4b and base 4. The boss 12 has a diameter slightly less than the larger diameter portion 1 lb but larger than the smaller diameter portion Ile of a keyhole slot in the mounting plate 11, whilst the relieved or undercut portion 1 2b of the boss 12 has a width, in the longitudinal direction of the base 4, which is lightly less than the diameter of the smaller diameter portion I 1c of the keyhole slot. The distance between the centres of the mounting aperture I la and keyhole slot I lb, 1 Ic approximates the distance between the centres of the sleeve 10 and boss 12, and the centre of the radiused end of the smaller diameter keyhole slot portion I lc will be appropriately oriented with respect to the mounting aperture 1 Ia, for example vertically above the centre of the latter.

Adjacent the edge 4e of the base 4, and laterally of the boss 12, the base is provided with a further and smaller depending integral boss 13. The height of the boss 13 approximates the distance between the plane of the underside of the base 4 and the common plane of the shoulders lOb and 12a.

The overall distance between the laterally outer extremities of the boss 13 and undercut portion 12b of the boss 12 is slightly less than the overall length of the keyhole slot.

To assemble the strain relief bushing to the mounting plate I I, the base 4 is tilted with the tip 4d of the lug 4a is inclined downwardly towards the mounting aperture I la to engage the shoulder 10h beneath the plate 11 adjacent the aperture I 1 a. The underside of the base 4 oriented as outlined at A in chain lines in Figure 11, is then pivotted about the shoulder towards the plate to engage the boss 12 in the larger diameter portion 11 b of the keyhole slot. In this position the boss 13 butts against the plate to one side of the keyhole slot and spaces the underside of the base 4, in the region of the edge 4e from the upper surface of the plate 11.

The base 4 in the region of the boss 12 is then pressed against the plate 11, resiliently flexing the base and fully engaging the boss 12 in the larger diameter portion llb of the keyhole slot. This aligns the undercut portion 12b of the boss 12 with the plate, and allows the base to be swung in a clockwise direction about the sleeve 10 and aperture 1 la, with the undercut portion 12b engaged in the smaller diameter portion 11 c of the keyhole slot, to the operative or anchored position outlined at B in dashed lines in Figure 11. As the base 4 reaches this position, the boss 13 reaches and snaps into the larger diameter end of the keyhole slot, thus positively locking the base against unintentional separational swinging movement in the reverse or anti-clockwise direction about the sleeve axis.

In this operative position, the sleeve 10 and boss 12 extend through the plate, and oppositely directed shoulders thereof are engaged beneath the plate, thus positively anchoring the base 4, and therefore the strain-relief bushing as a whole, to the plate.

The bushing may, however, be released intentionally by flexing up the edge 4e in the region of the boss 13 to disengage it from the keyhole slot, and then turning the base in an anti-clockwise direction to release the boss 12 entirely from the slot.

Either before or after the bushing is anchored to the plate as just described, an electrical cable may be clamped in the bushing as described with reference to Figures 1 to 6. However, in this embodiment, the portion of the cable which expends from between the pillars 5 and is flexed at right angles down through the aperture 4b will also pass through the sleeve 10 and be electrically insulated thereby from the plate Il. This portion of the cable will, for example, pass to the exterior of the appliance of which the plate 11 forms a part, whilst the portion of the cable on the other side of the pillars 5 will extend to the internal electrical connections of the appliance. Thus, the bushing will be located within the appliance with the end of the sleeve 10 projecting out of the appliance through the aperture I la. The bushing will resist longitudinal movement of the cable due to a tension being applied thereto as explained with reference to the first embodiment, and in addition, the abovedescribed anchorage of the bushing will prevent displacement and flexing of the bushing relative to the plate.

In order to prevent the portion of the cable externally of the appliance from being inadvertently or deliberately pressed back into the appliance through the plate 11, the second clamp portion 2 is preferably provided with an integral, relatively rigid, hollow lug or stop 14. When the clamp portion 2 is operatively locked onto the pillars 5, this stop 14 will overlie the aperture 4a and will be engaged by, and obstruct, the cable if pressed back into the appliance in a direction from below the base 4.

In order to enhance the clamping action of the first and second clamp portions on a cable, one or both portions, and for example the second clamp portion 2, may be provided with integrally molded, generally conical or otherwise pointed teeth 2c which bite into the clamped cable.

The device shown in Figures 12 to 17 comprises a strain relief bushing which is basically similar to that shown in Figures 7 to 11.

In this embodiment, however, the lug 4a and depending bush or sleeve 10 of the previous embodiment is replaced by a longitudinally extending sleeve or bush 20.

The sleeve 20 comprises a reduced diameter body portion 20a formed with a pair of diametrically opposed flats 20b, terminating in an enlarged diameter annular flange 20c.

A cable-receiving aperture 20d extends through the sleeve 20 in the longitudinal direction of the cable-receiving passage defined by the base 4, pillars 5 and second clamp portion 2.

The reduced diameter body portion 20a is formed with diametrically opposed upper and lower recesses 20e within each of which is located a pair of locking arms 21. These locking arms are integrally connected to the body portion 20a by their roots 21a and are resiliently depressible from their position shown into their associated recess 20e. The two locking arms of each pair are formed with locking shoulders 21b spaced by different distances from the rear face 20f of the flange 20c, and with inclined camming surfaces 21c. The mold core piece (not shown) which defines each recess 20e and the undersides of the associated pair of locking arms is, during molding of the strain relief bushing, extracted longitudinally of the bushing via the arcuate slots in the flange 20c, thus avoiding the necessity of breaking through the interior wall of the aperture 20b.

As will be apparent from Figure 13, the base 4 is stiffened by ribs 22, and the clamp portion 2 is formed with a pair of integral projections 23. It will also be apparent that the base 4 is narrower than in the previous embodiments, in that its width approximates the spacing between laterally outer surfaces of the pillars 5, and is less than the spacing between the flats 20b.

Additionally, the base 4 is provided with cable-gripping teeth 24, corresponding to the teeth 2c on the clamp portion 2.

The strain relief bushing is intended to be assembled to a mounting plate (not shown) provided with a mounting aperture having a diameter slightly larger than that of the body portion 20a, and also having one or two flats corresponding to the flats 20b.

Since, as will be apparent from Figure 17, the base 4 and ribs 22 lie within the diameter of the body portion 20a, and since the pillars 5 also lie within this diameter, the mounting aperture does not have to be enlarged or otherwise modified to accommodate these elements. The bushing is inserted generally longitudinally into the mounting aperture, clamp portion 2 first, until the body portion 20a enters the mounting aperture, with the flats of the body portion and mounting aperture in alignment, and the camming surfaces 21c of the two pairs of locking arms 21 engage the edge of the mounting aperture. The bushing is then pressed further through the mounting aperture, causing the locking arms 21 to be resiliently, cammingly depressed into their associated recesses 20e, until the rear face 20f of the flange 20c buts against the front surface of the mounting plate. In this position, depending upon the thickness of the mounting plate, some or all of the locking arms will resiliently snap out of their recesses behind the mounting plate so that their shoulders 21b will engage the rear edge of the mounting aperture to positively lock the bushing to the mounting plate. In particular, the maximum and minimum mounting plate thicknesses which the bushing may effectively accommodate will be determined by the spacing between the rear face 20f of the flange 20c and the locking shoulders 21b of the locking arm which is uppermost as viewed in Figure 14, whilst the intermediate plate thicknesses will be determined by the shoulders of the lowermost locking arm.

The locking arms 21 positively lock the bushing against unintentional axial displacement, whilst the cooperating flats of the body portion 20a and mounting aperture prevent the bushing from turning relative to the mounting plate. However, the bushing may be readily intentionally removed by depressing the locking arms, either manually or by means of an appropriate tool.

After the bushing has been snapped into the mounting aperture, the cable is threaded through the aperture 20d and between the pillars 5, and is clamped in place between the pillars by the clamp portion 2 as already described. Thus, the bushing locks the cable against unintentional longitudinal and rotational displacement relative to the mounting plate.

Any tendency for the base 4 and pillars 5 to flex towards the sleeve 20 when the outer end of the cable is pulled is resisted by the ribs 22, and also by the projection 23 on the clamp portion 2 which butt against the rear face of the body portion 20a.

In this embodiment, as in the previous embodiment, the sleeve 20 electrically insulates the cable from the mounting plate.

Since, during molding of the bushing, the recesses 20e are cored longitudinally, i.e. via the arcuate slots in the flange 20c, and not radially from within the aperture 20d, the internal surface of the aperture 20d is circumferentially uninterrupted, so that the risk of electrical contact between the cable and mounting plate through the sleeve 20 is eliminated.

From the foregoing, it will be seen that there are provided particularly advantgeous cable clamps and strain-relief bushings capable of accommodating a wide range of cross-sectional sizes and shapes of cable or other flexible elongate elements. In each embodiment, the maximum cable size is determined by the height of the pillars 5 and the diameter of the cable-receiving aperture 4Figures 1 to Il)or 20d (Figures 12 to 17), whilst the minimum cable size is determined by the closest position to the first clamp portion I in which the second clamp portion 2 can be locked.

Although the clamp or bushing may, if required, be released from the member or surface to which it is anchored, this is not mandatory when fitting or replacing cables, since the first and second clamp poritons 1 and 2 may be assembled and dis-assembled without disturbing the anchorage of the base 4.

It will be understood that the various modifications may be made without departing from the scope of the present invention as defined in the appended claims. For example, in each embodiment, the inter-engageable teeth on one or both of the clamp portions I and 2 may be replaced by other forms of adjustable locking elements. The locking elements may be provided on the inner surfaces and/or longitudinal end surfaces of the pillars in addition to the external surfaces thereof.

such locking elements being cooperable with correspondingly positioned locking elements on or in the clamp portion 2.

The clamp portion 2, instead of the clamp portion 1, may be provided with the means for securing the device to the surface or member of the electrical apparatus, and the strap 3, which in these specific embodiment extends longitudinally of, but to one side of, the cable-receiving passage, may be located to the other side of the passage, or the strap and clamp portion 2 may be located laterally of the passage and pillars. The shape, size and configuration of the clamp portions 1 and 2 may be changed.

The clamp shown in Figures 1 to 6 may be provided with cable-gripping teeth equivalent to the teeth 2c and/or 24 of Figures 7 to 17. Alternatively, in each embodiment, one or more of the cableengaging surfaces, for example the ribs 6a and 6b and/or the edges of the clamp portion 2, may be serrated, ribbed, or otherwise roughened, or the cable-receiving passage may be made more tortuous. The cross-sectional shape of the cable-receiving passage may be changed by changing the shapes of the inner surfaces of the pillars and base, and/or of the ribs 6a and 6b, or edges of the clamp portion 2 elsewhere on the underside of the base 4, and the location of the boss 13 may be similarly moved, so as to engage in a correspondingly located keyhole slot, although the boss 13 could locate in a separate aperture in the plate 11 or equivalent.

In the embodiments of Figures 1 to 11, the lug 4a may be cranked, for example through approximately 90 , so that the cable-receiving aperture 4b is generally longitudinally aligned with the cablereceiving passage between the pillars 5.

In order to produce an angled, for example right-angled, strain relief bushing, the sleeve 20 of the bushing of Figures 12 to 17 may be molded to the base 4 at an angle, for example at right angles to the position shown, i.e. corresponding to the position of the sleeve 10 in Figure 7. In this event, the bushing, at the juncture of the sleeve 20 and base 4, will be configured to permit the bushing to be threaded into and through an appropriate mounting aperture without difficulty. The sleeve 20 may, for example, be integrally or detechably connected to the base 4 or equivalent by means of a cranked tubular portion to guide the cable or equivalent.

The locking arms 21 may be increased or reduced in number, or may be replaced by other equivalent locking means.

WHAT WE CLAIM IS: 1. A clamping or securing device of the type specified, which comprises first and second element-locating portions molded from a synthetic plastics material and movable from a mutually open position, to a mutually closed position in which they define therebetween an element-receiving passage extending through the device, the first and second portions being provided with respective first and second locking means which are mutually cooperable to retain the portions in said closed position, and which are mutually adjustable to provide adjustement of the cross-sectional dimensions of the elementreceiving passage by relative bodily movement between the portions when in their closed position, thereby to accommodate, grip and restrain against longitudinal movement relative to the device, elongate elements of differing crosssectional dimensions when trapped in said passage, the first element-locating portion comprising a base formed integrally with two mutually spaced, generally parallel pillars defining, with the region of the base therebetween, a part of the elementreceiving passage, the pillars having regions extending lengthwise thereof provided, in a direction generally transverse to the element-receiving passage, with outwardly directed first locking means, the second element-locating portion comprising a closed loop, having transversely inwardly directed second locking means and, in the closed position of the portions, bridging and surrounding the pillars and being bodily slidable therealong, along a generally linear path, towards the base of the first portion.

2. A device as claimed in claim 1, wherein the second element-locating portion comprises a closed loop which is generally rectangular in plan.

3. A device as claimed in claim 1 or 2, wherein each of the pillars is provided with first locking elements, and the second portion is provided with second locking elements selectively cooperable with the first locking elements of the two pillars during said sliding movement to lock the second portion against separational movement thereof relative to the pillars, with a snap action, in one of a number of different adjusted positions.

4. A device as claimed in claim 3, wherein the first locking elements comprise transversely outwardly projecting ratchet like teeth distributed along the length of each pillar and resiliently cooperable with corresponding transversely inwardly projecting teeth comprising the second locking elements.

5. A device as claimed in any preceding claim, wherein the two element-locating portions are integrally connected by a flexible hinge or strap.

6. A device as claimed in claim 5, wherein the hinge or strap serves to guide one of the two element-locating portions as it is moved towards the other prior to engagement of the second portion with the pillars.

7. A device as claimed in any preceding claim, wherein one of the element-locating portions is provided with means to facilitate attachment of the device to a mounting surface or member.

8. A device as claimed in claim 7, wherein the first portion is provided with said attachment means, the base of the first portion being extended to one side of the pillars, in the generally longitudinal direction of the element-receiving passage, to form mounting means provided with an element-receiving aperture.

9. A device as claimed in claim 8, wherein said mounting means comprises a lug formed with said element-receiving aperture.

10. A device as claimed in claim 9, wherein the lug extends generally in the longitudinal direction of the elementreceiving passage, and the axis of said element-receiving aperture extends generally at right angles to the longitudinal direction of said passage.

I 1. A device as claimed in claim 9 or 10,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. elsewhere on the underside of the base 4, and the location of the boss 13 may be similarly moved, so as to engage in a correspondingly located keyhole slot, although the boss 13 could locate in a separate aperture in the plate 11 or equivalent. In the embodiments of Figures 1 to 11, the lug 4a may be cranked, for example through approximately 90 , so that the cable-receiving aperture 4b is generally longitudinally aligned with the cablereceiving passage between the pillars 5. In order to produce an angled, for example right-angled, strain relief bushing, the sleeve 20 of the bushing of Figures 12 to 17 may be molded to the base 4 at an angle, for example at right angles to the position shown, i.e. corresponding to the position of the sleeve 10 in Figure 7. In this event, the bushing, at the juncture of the sleeve 20 and base 4, will be configured to permit the bushing to be threaded into and through an appropriate mounting aperture without difficulty. The sleeve 20 may, for example, be integrally or detechably connected to the base 4 or equivalent by means of a cranked tubular portion to guide the cable or equivalent. The locking arms 21 may be increased or reduced in number, or may be replaced by other equivalent locking means. WHAT WE CLAIM IS:

1. A clamping or securing device of the type specified, which comprises first and second element-locating portions molded from a synthetic plastics material and movable from a mutually open position, to a mutually closed position in which they define therebetween an element-receiving passage extending through the device, the first and second portions being provided with respective first and second locking means which are mutually cooperable to retain the portions in said closed position, and which are mutually adjustable to provide adjustement of the cross-sectional dimensions of the elementreceiving passage by relative bodily movement between the portions when in their closed position, thereby to accommodate, grip and restrain against longitudinal movement relative to the device, elongate elements of differing crosssectional dimensions when trapped in said passage, the first element-locating portion comprising a base formed integrally with two mutually spaced, generally parallel pillars defining, with the region of the base therebetween, a part of the elementreceiving passage, the pillars having regions extending lengthwise thereof provided, in a direction generally transverse to the element-receiving passage, with outwardly directed first locking means, the second element-locating portion comprising a closed loop, having transversely inwardly directed second locking means and, in the closed position of the portions, bridging and surrounding the pillars and being bodily slidable therealong, along a generally linear path, towards the base of the first portion.

I 1. A device as claimed in claim 9 or 10,

wherein the lug is formed with one or more mounting apertures to receive fixing means for securing the device to a surface or member.

12. A device as claimed in claim 9 or 10, wherein the element-receiving aperture is defined by a tubular bush projecting from the lug on the opposite side thereof to the pillars, the bush being formed with locking means, cooperable with a surface or member when the bush is inserted into and through a corresponding aperture therein, to lock the device to the surface or member.

13. A device as claimed in claim 12, wherein the locking means on the bush is operable to lock the device to the surface or member by rotation of the device about the axis of the bush relative to the surface or member, and wherein means are provided on the base resiliently cooperable with the surface or member when the bush is inserted in the aperture in the surface or member and rotated to its locked position to prevent unlocking rotation of the device.

14. A device as claimed in claim 8, wherein said mounting means comprises a tubular bush defining the element-receiving aperture:

15. A device as claimed in claim 14, wherein the bush, and the axis of the element-receiving aperture, extend generally in the longitudinal direction of the element-receiving passage.

16. A device as claimed in claim 14 or 15, wherein the bush comprises a body portion which is at least part-circular in cross-section, and a flange projecting radially of the body portion at or adjacent the end thereof remote from the base, the body portion including means for anchoring the device within an aperture in a mounting member, with the mounting member located between the flange and anchoring means.

17. A device as claimed in claim 16, wherein said anchoring means comprise integral resilient locking arms which are deflectable from a locking position by cooperation with the mounting member to permit insertion of the device into the mounting aperture in the member, said locking arms being resiliently returnable towards their locking position behind the mounting member after insertion of the device, to lock the device to the mounting member.

18. A device as claimed in claim 16 or 17, wherein the second element-locating portion is provided with abutment means, cooperable with the body portion of the bush when the second element-locating portion is operatively assembled to the pillars, to prevent the pillars from flexing towards the bush.

19. A device as claimed in any preceding claim, wherein the first and second element locating portions are cooperable to define a tortuous element-receiving passage.

20. A device as claimed in anv preceding claim, including means within the elementreceiving passage to grip an element when located therein.

21. A clamping or securing device constructed substantially as hereinbefore described with reference to Figures 1 to 6 of the accompanying drawings.

22. A clamping or securing device constructed substantially as hereinbefore described with reference to Figures 7 to 11 of the accompanying drawings.

23. A clamping or securing device constructed substantially as hereinbefore described with reference to Figures 12 to 17 of the accompanying drawings.