GB2232192A

GB2232192A - Clamping device

Info

Publication number: GB2232192A
Application number: GB9006451A
Authority: GB
Inventors: Christopher Bispham
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-03-22
Filing date: 1990-03-22
Publication date: 1990-12-05
Also published as: GB9006451D0; GB8906671D0

Abstract

In a clamping device comprising two jaws (38) one of which can move along a runner (14, 16) a locking mechanism, suitable for securing a jaw to a runner is provided, in which a jaw guide (12) engages one side of a runner (14, 16) and a locking member (30) engages an underside (26, 28) of the runner, the locking member and jaw guide being securable about the runner by for example a screw-threaded actuation device (32). The jaws have clamping faces (38) which are inclined at an angle of less than 90 DEG to the longitudinal plane of the runner. <IMAGE>

Description

LOCKING MECHANISM The present invention relates to a locking mechanism and to a clamp (e g a vice) comprising said locking mechanism.

Vices and clamps of various types are known for holding or fixing objects in a desired position.

All such vices or clamps work on the principle of applying a force between two jaws to lock an object therebetween.

Vices working on a quick-release mechanism to enable speedy use, rely commonly on a two-stage process to fix or clamp an article between two jaws of the vice or clamp. In the first stage, a guide member is moved into close association with the article to be clamped whereupon the guide member is locked in place and then in a second process, the jaw member is adjusted to lock the article in question between the two jaws.

It is one object of the present invention to provide a locking mechanism which can be used to reduce this two-stage process to a one-stage process.

In accordance with one of its aspects the present invention provides a locking mechanism for locking a guide member to a pair of runners, which guide member is adapted to slide upon said runners, wherein a connecting member passes through said guide member and a locking member is associated with said connecting member at one side of the guide member whereby the locking member can be drawn up against the underside of said runners upon movement of the connecting member to lock said guide member to said runners, the connecting member having associated therewith at a second side of the guide member actuation means operable to move the connecting member and cause the locking member to be drawn up against said underside of said runners.

In accordance with another aspect of the present invention there is provided a locking mechanism for locking a guide member to a pair of runners, which guide member is adapted to slide upon said runners, wherein a threaded rod passes through said guide member and a locking member in the form of a locking nut is received on the threaded rod and can be drawn up against the underside of said runners to lock said guide member thereto.

Preferably, said guide member has a jaw extending from a leading end and a restraining bar at the end remote from the leading end. The restraining bar may be arranged to act to prevent backing off of the guide member when it is locked to said runners and also to aid in pivoting the jaw associated with said guide member in a direction towards an article being clamped.

As well as lacking speed of use, vices or clamps of the prior art lack the ability to retain many objects satisfactorily. The object which is being retained by the two jaws of a clamp or vice can be easily damaged by the compressive forces exerted by the jaws of said clamps or vices. Furthermore, the vices and clamps of the prior art are generally unable to cope with objects which are of an unusual shape due to the fact that the forces exerted by such vices act only directly between the two jaws of the vice. This problem is particularly acute with cylindrical articles, such as piping, where there is a limited area upon which the clamping force can be exerted. Problems also exist with fragile objects and those which bend easily, such as hollow section ducting and tray metal.By retaining such articles on more than one side and at the same time distributing the retaining force about the object, this problem can be alleviated.

Thus, a further object of the present invention has been to provide a clamp or vice which can effectively clamp awkward objects.

In accordance with a further aspect of the present invention there is provided a clamp device, such as a vice, having two jaws and a runner operable to retain an object therebetween, at least one jaw being arranged to run along said runner when in a released condition and the other being movably mounted or fixed to said runner, said jaws have associated therewith clamping faces which are inclined at an angle of less than 90" to the longitudinal plane of said runner.

Preferably, said at least one jaw comprises a locking mechanism which enables it to be locked onto said runner such that its clamping face acts on the object in both the longitudinal plane of the runner and in a direction perpendicular to that plane as the jaw is tightened.

In one embodiment, this has been achieved by tightening the jaw to the runner such that, as the jaw is tightened, its clamping face moves or tends to move both across and down onto the object being clamped. This effect can be achieved by having the clamping faces angled and can be enhanced by providing the guide member upon which the jaw is mounted with a restraining bar at its end remote from the clamping face.

In one embodiment, the locking mechanism comprises a channel section member which has runners upon which there runs a guide member. One side of the guide member is adapted to form or has fitted thereto, a jaw member and, passing through said guide member there is a threaded rod, one end of which is attached to a handle and the other end of which is attached to a locking nut. The locking nut is adapted to run in the channel between the side flanges of the channelled section member and lock to inturned parts thereof when tightened.

Preferably, the side remote from the jaw member is provided with a thin restraining bar on its underside, which restraining bar will grip the runners of said channelled section member when the handle is turned during the locking of the guide member thereto. The restraining bar helps to prevent backing off of the guide member.

In the embodiment described above, the locking mechanism forms part of a vice or clamp but in other embodiments it could provide a joint assembly for assembling structures such as market stalls.

By way of example only, specific embodiments of the present invention will now be described with reference to the accompanying drawings in which: Figure 1 is an end view showing a locking mechanism of the present invention; Figure 2 is a cross section through a vice or joint assembly having a locking mechanism of the present invention, and Figure 3 is a perspective view of a vice having the locking mechanism of Figure 1.

The locking mechanism 10 comprises a guide member 12 which is adapted to slide along two runners 14 and 16 forming parts of a channel section steel member 18.

The channel section member 18 is of U-shaped configuration. It has a base or web 20 from which there extends, in a direction perpendicular thereto, two flanges 22 and 24 which are each folded back upon themselves thereby to form the runners 14 and 16.

The folded back portions end short of the base 20 thereby to form a second set of runners 26 and 28 upon which a locking nut 30 runs and acts. The locking nut 30 has formed therein grooves 31 which act to guide it along the second set of runners 26 and 28.

The grooves have teeth (not shown) projecting therefrom, which teeth can bite into the second set of runners 26 and 28 when the nut is tightened, thereby preventing the guide member 12 from backing off. The locking nut 30 is connected to the guide member 12 via a threaded bolt 32. The threaded bolt has a steep pitch so that only a small turn thereof brings the locking nut in engagement with the second set of runners 26 and 28 on the U-shaped channel member. Thus, on turning handle 34 which projects perpendicularly from the bolt to aid leverage, locking nut 30 is drawn up against the second set of runners 26 and 28 of the U-shaped channelled member, thereby locking the guide member 12 in position. A first part of the turn of the handle meshes the rear of the guide member 16 with the runner, preventing backing off.A second part urges the jaw forward to give a clamping action.

The guide member 12 may have at one end thereof a restraining bar 36 (see Figure 2) which acts against the runners 14 and 16 of the channelled member 18, preventing backing off during tightening of the nut, and which also artificially elevates the end remote from the jaw face 38, enabling the guide member to pivot as it is locked. A pivoting of the guide member therefore exerts a clamping force which is not parallel to the runners of the channel section member and which can improve the clamping. This restraining bar can also be grooved to enable it to slide over the runners more easily.

In the assembly illustrated by Figure 2 the guide member 12 is adapted to provide one jaw 38 of a vice, clamp or joint assembly held at substantially 90" to the channelled member, enabling it to grip a variety of objects including other channelled members and other members which may extend above the jaws.

The resulting force exerted by these jaw members will be inclined at a slight angle from the vertical, eg between 0 and 100 by virtue of action of the restraining bar 36.

In the vice illustrated in Figure 3, the guide member 12 is adapted to form one jaw 38 of a vice or clamp by extension therefrom of a member which is inclined at an angle to the runners. Preferably the jaw member is inclined at an angle of between 300 and 600, and more preferably 450 to the runner.

By using two such angled members, a vice or clamp is formed and is ideal for clamping metal trays, and other articles which could be easily damaged. The use of two angled jaws which project over the article being clamped means that forces can be exerted in several directions by a single vice or clamp.

If the mechanism is to be used as a way of clamping together market stalls or the like, the handle may be replaced by a fitting which would accept a hexagonal socket key or the like and the jaw member may be L-shaped to enable other channel members making up the stall's structure to be completely enclosed.

Claims

CLAIMS:

1. A locking mechanism for locking a guide member to a pair of runners, which guide member is adapted to slide upon said runners, wherein a threaded rod passes through said guide member and a locking member in the form of a locking nut is received on the threaded rod and can be drawn up against the underside of said runners to lock said guide member thereto.

2. A locking mechanism for locking a guide member to a pair of runners, which guide member is adapted to slide upon said runners, wherein a connecting member passes through said guide member and a locking member is associated with said connecting member at one side of the guide member whereby the locking member can be drawn up against the underside of said runners upon movement of the connecting member to lock said guide member to said runners, the connecting member having associated therewith at a second side of the guide member actuation means operable to move the connecting member and cause the locking member to be drawn up against said underside of said runners.

3. A locking mechanism according to claim 2 wherein the actuation means comprises a cam surface inclined to an axial direction of movement of the connecting member through the guide member.

4. A locking mechanism according to claim 3 wherein the cam surface is provided on said second side of the guide member and co-operates with a cam member associated with the connecting member.

5. A locking mechanism according to claim 4 wherein relative rotation of the connecting member and guide member arises from movement of the cam member and cam surface and results in an axial direction of movement of the connecting member through the guide member.

6. A locking mechanism according to any one of claims 2 to 5 wherein the actuation means comprise an operating handle associated with the connecting member at a second side of the guide member.

7. A locking mechanism according to any one of claims 2 to 4 wherein the actuation means comprises said connecting member in the form of a threaded rod.

8. A locking mechanism according to claim 1 or claim 7 wherein threaded rod engages with a screwthread formation in either the guide member or the locking member.

9. A locking mechanism according to any one of claims 1, 7 or 8 wherein the threaded rod has an associated therewith actuation means comprised by an operating handle at a side of the guide means remote from the locking member.

10. A locking mechanism according to any one of the preceding claims wherein as considered in the direction of the length of said runners the guide member has a jaw extending from its leading end.

11. A locking mechanism according to any one of the preceding claims wherein as considered in the direction of the length of said runners the guide member has at its end remote from the leading end a restraining bar arranged to prevent backing off of the guide member when it is locked to said runners.

12. A locking mechanism according to claim 11 when dependent on claim 10 wherein when the locking mechanism is used to clamp an article said restraining bar aids in pivoting said jaw in a direction towards the article.

13. A locking mechanism according to claim 1 or claim 2 and constructed and arranged substantially as hereinbefore described with reference to the accompanying drawings.

14. A clamp device comprising two jaws and a runner operable to retain an object therebetween, at least one jaw being arranged to run along said runner when in a released condition and the other being movably mounted or fixed to said runner, said jaws having associated therewith clamping faces at least one of which is inclined at an angle of less than 900 to the longitudinal plane of said runner.

15. A clamp device according to claim 14 wherein said at least one jaw comprises a locking mechanism which enables it to be locked onto said runner such that its clamping face acts on the object in both the longitudinal plane of the runner and in a direction perpendicular to that plane as the jaw is tightened.

16. A clamp device according to claim 14 or claim 15 wherein tightening of said at. least one jaw to the runner causes the clamping face of the jaw to tend to move both across and down onto an object being clamped.

17. A clamp device according to any one of claims 14 to 16 wherein said at least one jaw is provided with a restraining bar on its side remote from the clamping face thereby to assist the clamping face to tend to move both across and down onto an object being clamped.

18. A clamp device according to claim 14 and constructed and arranged substantially as hereinbefore described with reference to the accompanying drawings.

19. A clamp device according to any one of claims 14 to 18 wherein a pair of runners are provided and the device comprises a locking mechanism according to any one of claims 1 to 13 with the guide member of said mechanism being associated with said at least one jaw.

20. A clamp device according to claim 19 or a locking mechanism according to any one of claims 1 to 13 wherein the runners are comprised by side portions of a channel section member.

21. A device or mechanism according to claim 20 wherein said side portions are of a folded construction in which material of each side portion is folded at a region remote from a base portion interconnecting the side portions such that edge material of the side portion faces in a direction towards the base portion.

22. A device or mechanism according to claim 21 wherein the folded material of a side portion lies within the channel section.

23. A device or mechanism according to claim 21 or claim 22 wherein the locking member engages inturned edges of the side portions of the channel section when in a locked condition.

24. A device or mechanism according to any one of the preceding claims wherein the locking member is restrained from rotation relative to a runner.