GB2281755A - A rapidly adjustable clamp - Google Patents

Abstract

A clamp, eg for securing a ladder/s to a roof rack, comprises an over-centre latch bracket 18 that is adjustable along tube 10 via an elongate slot 11 in which slides pin 19. A hook 15 is pivotally attached to the bracket 18 by pivot pin 14. The bracket 18, pin 19 and hook 15 are slid along tube 10 until the required distance is reached and the pin 19 is then inserted into a notch 12, the bracket 18 is then pressed downwards, pivoting about pin 19, towards tube 10 resulting in the hook 15 moving downwards thereby clamping an object. With the object clamped, holes 16 and 20 align so that the clamp may be suitably padlocked (fig 3). Cushioning sleeves 21, eg of rubber, are provided to aid grip and for protection. The hook 22 may be rotatable and fixed axially or vice-versa (fig 4). A double headed clamp bar (15b, fig 5) may be provided. The adjusting mechanism may alternatively be in the form of a locking cam (see fig 6). <IMAGE>

Description

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Field of the Present Invention THIS PRESENT INVENTION RELATES TO A SECURITY CLAMP SPECIFICALLY FOR TELESCOPIC LADDERS BUT COULD APPLY TO OTHER ITEMS WHICH NEED TO BE SECURED TOGETHER.

Background to the Present Invention Prior art has described a security device which can be passed through the hollow staves of a telescopic ladder to secure the ladder to the roof rack of a motor vehicle or to other fixed objects. Pat: App: No 9310523.7 (21.5.93) dated 9303613.5 (23.2.93) refers. (Put your Pat: Off: Filing No & Date) The criteria for the aforesaid device is the hollow stave of the ladder. The present invention is devised to secure any ladder or plurality of ladders together or to a roof rack of a motor vehicle or to any other suitably fixed object.

The embodiment comprises a length of hollow square or rectangular cross-sectioned steel tubing which is racked and slotted to provide rapid adjustment for a hooked clamp bar and a latching bracket. At one distal end of the tubular member is provided a swivelling hook which aligns with the hooked clamp bar.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Positioned forward of the elongate slot and the racking feature along the hollow steel tube is provided a plurality of holes which will align with any position at which the hooked clamp bar is located. The holes will accept the staple of any padlock and so retain the said clamp bar and the swivelling hook in a locked position. The latch bracket provides the over-centre feature which causes the hooked clamp bar to draw tightly against any object about which it has been placed. When the latch is manually forced downwards against the hollow steel tube through the clamp bar, latch bracket and hollow steel tube will align together to provide the lockable position.

Both the swivelling hook and the hooked clamp bar are provided with soft covers of rubber, plastic or other suitable material to obviate a metal to metal contact and to prevent chafing between the hook bars and the objects about which they are clamped.

Several embodiments of the present invention will now be more particularly described solely by way of example with reference to the accompanying drawings in which.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Figure 1 is an assembly drawing of the complete LATCHED CLAMP Figure 2 is an exploded view of the component parts of the LATCHED CLAMP Figure 3 shows the LATCHED CLAMP suitably padlocked Figure 4 illustrates a LATCHED CLAMP with two hooked clamp bars Figure 5 shows the LATCHED CLAMP with an alternative end fixing.

Figure 6 introduces an alternative method of length adjustment for the two clamp bars.

DescriDtion of the Preferred Embodiments Referring to Figure 1 there is shown a length of square section steel tube 10 through which, along its long axis is provided an elongate slot 11. Along one edge of the elongate slot 11 is provided a plurality of serrations or notches 12, which form a rack feature. Approximately adjacent to the notches 12 is provided a plurality of holes 13 which will accept the staple of an appropriate padlock.

(see Figure 3).

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Extending above the tube 10 and pivotal upon a fulcrum pin 14 is the upper hook bar 15, somewhat "U" shaped and constructed in round hardened high tensile steel. The pivotal end of the hook bar 15 is flattened to provide the hole for the fulcrum pin 14 and for a larger diameter hole 16 drilled forward of the through pin 14 hole.

The flattened end 17 of the hook bar 15 is angled to the vertical axis of the hook bar 15 and, as will be seen subsequently, can be drawn downwards by the action of the latch bracket 18.

Figure 1 shows the latch bracket 18 in the "release" position throughout the length of the elongate slot 11 by inserting a through pin 19 (see Figure 2) into any one of the notches 12. It will be obvious that with the pin 19 located in the notches 12 the latch may be fulcrumed upon it and can be manually forced downwards taking with it the hook bar 15.

When the latch 18 is fully depressed against the tube 10 the holes 16 in the hook bar 15 and the hole 20 in the latch bar 18 will align with the appropriate hole 13 in the tube 10.

The hook bar 15 will of course be drawn tight against any object about which the hook has been placed.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Shown positioned on the upper horizontal elements of the hook bar 15 are soft rubber plastic or other appropriate material cushioning sleeves 21 so provided to add grip to the hook bar 15 and to prevent metal to metal contact with subsequent chaffing. At the lower distal end of the hollow steel tube 10 is provided a swivelling hook bar 22. The steel tube is shown cut-away to indicate how the hook bar 22 is secured in amend plate 23, fixedly attached to the said tube by welding or some other means. The end of the hook bar 22 within the steel tube 10 is provided with an annular groove 24 which enables the hook bar 22 to rotate freely about the lower distal end of the said tube 10.

Referring now to Figure 2 the various components which comprise the LATCHED CLAMP are illustrated separated from the steel tube. It can be seen from Figure 2 that the through pin 19 can engage with anyone of the notches 12 along the elongate slot 11. It can also be seen that the hook bar 15 ad the latch bracket 18 engaging freely together on fulcrum pin 14 and that the said pin is not inserted through the steel tube 10. The through pin 19 passes through the hook bar 15 first then the latch bracket 18 and into the elongate slot 11.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP The assembly of hook bar 15, latch bracket 18 and the through pin 19 can then slide along through the elongate slot 11 to any position which will ensure the clamp bar 15 can be engaged about any object/s it is desired to encompass and secure. The through pin 19 will then be manually pushed into the appropriate notch 12 and the latch bracket 18 pressed downwards towards the steel tube 10 to apply pressure on the object by the soft sleeves 21. At that position the holes 16 and 20 will be in alignment and may be suitably padlocked as Figure 3 will show and to which attention may now be directed. Further text is deemed to be unnecessary as it will be obvious from the description given in relation to Figures 1 and 2 that the LATCH CLAMP can be padlocked by inserting the lasp 25 of the padlock 26 through the aligned holes 16 and 20.

Reference is now made to Figure 4 which introduces two length adjustable clamp bars. The swivelling hook bar 22 is replaced by a clamp bar 15a which can be traversed through a separate elongate slot 27 to any one of the notches 28 provided along the forward edge of the said slot 27. Note that the notches 28 are slightly recessed 29 to enable the latch pin 30 to lodge more securely in any notch 28 that may be appropriate. The upper clamp bar 15 and latch bracket 18n remain similar to those described for Figures 1 and 2.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP The steel tube 10 is reinforced in this embodiment by a strengthening rib 31 extending throughout its length. The latch bracket 18 is shown in the latched and therefore lockable position. It should be noted that lower clamp bar 15a is provided with a cross brace 32 which traverses along the front face (as viewed) of the steel tube 10.

Another embodiment which introduces a more rigid end fixing for the LATCHED CLAMP and provides a double headed clamp bar 15b is shown in Figure 5.

The end fixing 33 comprises a clamp plate 34 which can be releasably bolted about any suitable fixture (not shown) by the two bolts 35. The latch bracket 18, elongate slot 11 and notches 12 remain the same as described for Figures 1 and 2. In Figure 5 the latch bracket 18 is shown in the lockable position.

The double headed clamp bar 15b is provided with three soft rubber, plastic or other material sleeves 36. Alternatively the clamp bar 15 (Figure 1 and 2) may be provided with this more rigid fixing of the steel tube 10. The double headed clamp bar 15b might be more suitable for objects which need to be releasably secured each side of the steel tube 10.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP Referring now to Figure 6 there is shown an alternative method of length adjustment for a clamp bar 15c and a swivelling hook bar 22a. The tube 10 has been substituted by two steel tubes 37,38. Tube 37 slides within tube 38 and is provided with a centrally orientated elongate slot 39 through the two sides 40,41. The rear side 42 is provided with spur gear teeth 43 along its internal face. The forward side 44 is cut away for a considerable proportion of its length as indicated by numerals 45 to provide for the operation of a locking cam 46 which would abut against the inner face of side 47 of tube 38 when assembled.

The upper clamp bar 15c is fitted into an anchor bolt 48 in the end cap 48a the tube 37. The lower swivelling hook bar 22a is fitted to the lower end of tube 38 in a similar manner to that described for hook bar 22 in Figure 1 and 2.

The latch bracket 49 in this embodiment is not employed to draw the clamp bar 15c and the swivelling hook bar 22 towards each other as previously described but becomes lockable when closed over a staple 50 fixedly attached to the outer face 51 of tube 38. figure 6 illustrates the component parts comprising this alternative embodiment in "exploded" view to show more particularly the principle of operation - which otherwise might not be understood. The scrap view 6a indicate the locking action of the cam 46.

ADJUSTABLE CAPTIVE OVER-CENTRE LATCHED CLAMP The tubes 37 can move vertically upward through tube 38 with the cam 46 travelling along the gear track 43. When tube 37 is manually depressed into tube 38 the cam 46 will abut against the inner face of side 47 of tube 38.

While the constructional operations to produce the alternative embodiment described in relation to Figure 6 are likely to be more costly the inherent principle remains the same as those described for the Figure 1 to 5.

Claims (11)

1. A security clamp comprising lower and upper longitudinally-adjustable retaining elements connected together via a longitudinal support member, the upper retaining element comprising a latch bracket which is pivotable between an open condition which permits longitudinal adjustment to take place and a closed condition in which the latch may be locked to prevent longitudinal relative movement of the retaining elements.

2. A clamp according to claim 1, in which the support member includes a longitudinal adjustment slot provided with a plurality of notches, and the upper retaining element is carried in the slot for engagement in a selected notch.

3. A clamp according to claim I or claim 2, in which the latch bracket is pivotable to an over-centre position in the closed condition.

4. A clamp according to any preceding claim, in which the support member is provided with an array of lateral holes to receive the staple of a padlock to lock the latch bracket in the closed condition.

5. A clamp according to any preceding claim, in which the lower retaining element comprises a hook member.

6. A clamp according to claim 5, in which the hook member is axially pivotable about the support member.

7. A clamp according to any preceding claim, in which the lower retaining element is longitudinally adjustable with respect t the suppcrt member.

8. A clamp according to claim 1, in which the support member comprises telescopically-slidable tubes which are lockable together by means of an internal jammable cam element rotatably carried by the outer tube and having teeth which engage a gear rack formed on the internal wali surface of the inner tube.

9. A clamp according to any preceding claim, in which the retaining elements comprise a resilient material.

10. A clamp substantially as hereinbefore described with reference to and as illustrated in any of Figures 1 to 5 of the accompanying drawings.

11. A clamp substantially as hereinbefore described with reference to and as illustrated in Figure 6 of the accompanying drawings.