GB2272175A - Vice - Google Patents

Abstract

The vice (10) has a jaw (14) fixed to a frame (12) and a movable jaw (24). A handle (20) turns a slide bar (18) of square section on which slides an adjustment member (32). The adjustment member screws into and out of a screw member (28) secured to the movable jaw. A catch plate (40) jams the adjustment member on the slide bar except in an end position (shown) where the screw member squares the catch plate relative to the slide bar enabling the movable jaw assembly (22) to slide along the bar (18). <IMAGE>

Description

VICE ARRANGEMENT This invention relates to a vice arrangement of the type comprising a frame mounting a fixed jaw and a movable jaw, the movable jaw being moved by a screw to clamp objects between the jaws. The invention particularly relates to a vice arrangement having two screws in parallel connected to the movable jaw enabling asymmetric clamping between the jaws. Such an arrangement is particularly useful when the jaws are formed as the surface of a workbench, such as described in GB-A-1267032.

EP-A-0222477 discloses such a vice/workbench assembly in which the fixed jaw is removable and replaceable at different locations to adjust the available width for clamping objects of different sizes.

WO-A-9214581 discloses a clamping device in which a ratchet mechanism is provided between the clamping device and the movable jaw, whereby the jaw can be moved freely up to or away from the fixed jaw (or object disposed between) when the ratchet arrangement is released. In this arrangement, the ratchet arrangement includes a bar passing through, and jamming in, an aperture of a plate inclined with respect to the bar. However, such an arrangement does not employ a screw system which is very satisfactory in providing fine adjustment to clamping forces and for other reasons. Moreover, the ratchet must actively be disengaged to release the clamp.

Thus it is an object of the present invention to provide a vice arrangement which has the ability freely to move one jaw with respect to the other and which is screw operated for tightening and loosening the jaws, an operator of the arrangement not being required separately to activate or deactivate a latching or ratchet mechanism to engage or disengage the screw from the movable jaw.

In accordance with the present invention, there is provided a vice arrangement comprising: a frame; a fixed jaw in the frame; a selectively rotatable slide bar fixed in the frame; and, a movable jaw assembly, which assembly comprises a) a movable jaw in the frame, adapted to move towards and away from the fixed jaw to clamp objects therebetween; b) a screw member, rotationally fixed with respect to said movable jaw; c) an adjustment member, in threaded engagement with the screw member and being slidable on and rotationally fixed with respect to said slide bar; and, d) jamming means, disposed between said adjustment and screw members; said jamming means being released in a first position of said adjustment member with respect to said screw member, enabling said assembly to slide back and forth on said slide bar, while rotation in a first direction of said slide bar displaces said adjustment member from said first position to engage said jamming means with said slide bar, further rotation of said slide bar serving to clamp an object between said jaws.

Preferably said screw member is concentric with said adjustment member. Preferably said movable jaw is fixed on said screw member and said slide bar passes rotationally freely through said screw member.

Preferably said jamming means comprises a catch plate rotationally fixed on the slide bar and in said first position is square to the bar but on rotation of said slide bar is permitted by relative displacement of said screw and adjustment members to tilt with respect to the slide bar. The catch plate may be spring biased towards its tilting position.

Where it is the screw member which is axially fixed to the movable jaw, it is the adjustment member which is jammed on said slide bar by said jamming means.

Preferably said adjustment member has radially opposed slots which capture said catch plate, and permit tilting of the catch plate, the screw member in said first position pressing the catch plate against sides of the slots, which sides are square with respect to the slide bar, a spring captivated by said adjustment member around the slide bar urging said catch plate towards opposite sides of said slots, which sides are inclined with respect to the slide bar.

The invention is further described hereinafter, by way of example only, with reference to the accompanying drawings, in which: Figure la is a side section through a vice arrangement according to the present invention; Figure lb is a side section, partly cut away, of a different embodiment to the arrangement shown in Figure la; Figures 2a, b, and c are views of a screw member employed in the embodiment of Figure la, Figure 2a being an end elevation, Figure 2b being a side elevation and Figure 2c being a section along the lines c-c in Figure 2a;; Figures 3a to d are views of an adjustment member as used in the embodiment of Figure la, Figure 3a being a side section along the line a-a of Figure 3b, Figure 3b is a top plan view in the direction of the arrow b in Figure 3a, Figure 3c is a bottom plan view in the direction of the arrow c in Figure 3a, and Figure 3d is a section along the line d-d in Figure 3b; and, Figure 4a and b are views of a catch plate as employed in the embodiment of Figure la, Figure 4a being a front elevation and Figure 4b being a section along the line b-b in Figure 4a.

With reference to Figure la, a vice arrangement 10 comprises a frame 12 to which a fixed vice jaw 14 is connected by bolts 16. A slide bar 18 is axially fixed in the frame 12 and has at one end protruding through the front of frame 12, a handle 20 by which the slide bar 18 may be rotated. The slide bar 18 is of constant crosssection along its length, which section is not circular and is preferably square. A movable jaw assembly 22 is mounted on the frame 12 and the slide bar 18. The assembly 22 comprises a movable jaw 24 which is adapted to move towards and away from fixed jaw 14 in order to grip objects placed between them. Each jaw 14,24 is mounted on an intermediate member 26, and in the case of the movable jaw 24 a bolt 28 connects the movable jaw 24 through the intermediate member 26 securely to a screw member 28.The screw member 28 protrudes through a slot 30 in the frame 12 and is guided thereby on shoulders 29 (see Figure 2a) of the screw member 28. The screw member 28 has an internal threaded bore 30 into which is threaded an adjustment member 32. The slide bar 18 passes through a bore 34 of the adjustment member 32 and also a bore 36 of the screw member 28. The bore 34 is a close sliding fit on the slide bar 18, so that rotation of the slide bar 18 rotates the adjustment member 32 screwing it into and out of engagement with the threaded bore 30 of the screw member 28. However, the bore 36 of the screw member 28 is sufficient to enable the slide bar 18 to rotate freely inside.

Axial movement of the adjustment member relative to the screw member is limited at one end by shoulders 38 around the bore 36 of the screw member 28, and at its other end by a catch plate 40. The catch plate 40 is a close sliding fit on the slide bar 18 when it is square with respect to the slide bar 18. The catch plate 40 is retained between slots 42,44 in the adjustment member 32 and abuts shoulders 46 formed around the inside of that end of the screw member 28. Indeed, when the adjustment member 32 is in a first position as shown in Figure la, sides 42a,44a of the slots 42,44 press the catch plate 40 against the shoulders 46 of the screw member 28. In this first position, and by virtue of the alignment of the sides 42a,44a of the slots 42,44, and also the alignment of the shoulders 46, the catch plate 40 is held square with respect to the slide bar 18. Thus in this first position, the movable jaw assembly 22 is freely movable along the slide bar 18 towards and away from the fixed jaw 14.

When, however, the handle 20 is rotated in a first direction, turning the adjustment member 32 and screwing it into engagement with the threaded bore 30 of the screw member 28, the support of the shoulders 46 is taken away from the catch plate 40. A spring 48 is carried in the adjustment member 32 and serves to press the catch plate 40 towards the opposite sides 42b,44b of the slots 42,44.

These sides are not aligned parallel with respect to the other sides 42a,44a, and consequently the catch plate 40 is tilted with respect to the slide bar 18 and so it jams on it. In jamming, the catch plate 40 prevents the adjustment member 32 from travelling rightwardly (in the drawing of Figure la) with respect to the slide bar 18.

As a consequence, continued rotation of the slide bar 18 must draw the screw member leftwardly (in the drawing of Figure la). Simultaneously the movable jaw 24 is drawn towards the fixed jaw 14 within the limits imposed by the adjustment member 32 ultimately abutting the shoulders 38 of the screw member 28. However, this permitted amount of travel should be sufficient to clamp an object placed between the jaws 14,24.

When it is desired to release the object clamped between the jaws 14,24, the handle 20 is rotated in the reverse direction screwing the adjustment member 32 towards the position shown in Figure la and ultimately bringing the catch plate 40 into engagement with the shoulders 46 of the screw member 28 so that the catch plate is again rendered square with respect to the slide bar 18. If the object clamped between the jaws 14,24 has not already been released by the unscrewing of the screw member 28 from the adjustment member 32 while that was still jammed on the slide bar 18, then, when the catch plate 40 is released from the slide bar 18, the movable jaw 24 can be moved manually to release further the object clamped between the jaws.It should be noted, that in any position of the adjustment member 32 in the screw member 28, after an object has been clamped between the jaws and it is desired to release the object, unscrewing of the adjustment member 32 will not only tend to open the jaw 24 by displacing rightwardly the screw member 28 but also will draw the adjustment member 32 leftwardly in the drawing tending to release the catch plate 40 from jamming engagement with the slide bar 18 before the position shown in Figure la is reached.

In the embodiment shown in Figure la, when an object is tightened between the jaws 14,24 the slide bar 18 is placed under tension equal to the force applied to the object being clamped. This force is transmitted through the catch plate 20 to the sides 42b,44b of the slots 42,44 of the adjustment member 32. These sides 42b,44b are supported by limbs 50 (see Figure 3d) between the slots 42,44. Figure 1b shows a different embodiment which is essentially the same as that shown in Figure la but turned around.

In this arrangement, the adjustment member 32' pushes the catch plate 40 rather than pulling it as in the Figure la embodiment. Indeed, the arrangement is substantially identical, except that the threaded interaction between the adjustment member 32 and screw member 28 has been moved to the other side of the jamming means 40.

The adjustment member 32' is likewise a sliding fit on the slide bar 18 and has a shoulder 52 limiting movement of the screw member 28' along the adjustment member 32'. Movement is limited in the other direction by the catch plate 40, which, when shoulders 46' of the screw member 28' come into contact with it, serve to render the catch plate 40 square with respect to the slide bar 18. This first position is equivalent to the position shown in Figure la. When the adjustment member 32' is screwed into the screw member 28' from this position by rotation of the slide bar 18, shoulders 46' move away from the catch plate 40 and allow it to tilt against the inclined surface b' of the slots 42',44' in the adjustment member 32'. Before abutting the side b' of the slot 42', the catch plate 40 jams on the slide bar 18 and locks the adjustment member 32' with respect to the slide bar 18.Thus further screwing of the adjustment member 32' in to the screw member 28' draws the movable jaw 24 towards the fixed jaw 14.

Other alternative embodiments of the present invention are feasible. For example, the movable jaw may be connected to the adjustment member through a rotationally free but axially fixed connection. In this case the screw member is rotationally fixed but axially freely connected to the movable jaw and the jamming means is arranged to lock the screw member with respect to the slide bar when the adjustment member is rotated. Other less practical alternatives also exist.

Finally, two handles 20, slide bars 18 adjustment members 32 and screw members 28 may be provided between the fixed and movable jaws 14,24. This enables asymetric clamping between the jaws if the movable jaw is rotatable, at least to some extent about a vertical axis with respect to the screw member 28. For this purpose the intermediate mounting member 26 may allow rotation about the bolt 25 on the screw member 28. Moreover, the jaws î4,24 may be provided with an extended surface forming the worksurface of a work bench.

Claims (10)

1. A vice arrangement comprising: a frame; a fixed jaw in the frame; a selectively rotatable slide bar fixed in the frame; and, a movable jaw assembly, which assembly comprises a) a movable jaw in the frame, adapted to move towards and away from the fixed jaw to clamp objects therebetween; b) a screw member, rotationally fixed with respect to said movable jaw; c) an adjustment member, in threaded engagement with the screw member and being slidable on and rotationally fixed with respect to said slide bar; and, d) jamming means, disposed between said adjustment and screw members; said jamming means being released in a first position of said adjustment member with respect to said screw member, enabling said assembly to slide back and forth on said slide bar, while rotation in a first direction of said slide bar displaces said adjustment member from said first position to engage said jamming means with said slide bar, further rotation of said slide bar serving to clamp an object between said jaws.

2. A vice arrangement as claimed in claim 1, in which said screw member is concentric with said adjustment member.

3. A vice arrangement as claimed in claim 1 or 2, in which said movable jaw is fixed on said screw member and said slide bar passes rotationally freely through said screw member.

4. A vice arrangement as claimed in any preceding claim, in which said jamming means comprises a catch plate rotationally fixed on the slide bar and in said first position is square to the bar but on rotation of said slide bar is permitted by relative displacement of said screw and adjustment members to tilt with respect to the slide bar.

5. A vice arrangement as claimed in clause 4, in which said catch plate is spring biased towards its tilting position.

6. A vice arrangement as claimed in any preceding claim, in which it is the screw member which is axially fixed to the movable jaw, and it is the adjustment member which is jammed on said slide bar by said jamming means.

7. A vice arrangement as claimed in claims 4 and 6 or in claims 5 and 6, in which said adjustment member has radially opposed slots which capture said catch plate, and permit tilting of the catch plate, the screw member in said first position pressing the catch plate against sides of the slots, which sides are square with respect to the slide bar, a spring captivated by said adjustment member around the slide bar urging said catch plate towards opposite sides of said slots, which sides are inclined with respect to the slide bar.

8. A vice arrangement as claimed in any preceding claim, in which two slide bars, screw members and adjustment members are disposed in parallel between said fixed and movable jaws, and in which the movable jaw is at least to some extent rotatable about an axis perpendicular the axis of slide bar and the movable jaw face.

9. A vice arrangement as claimed in claim 8, in which said fixed and movable jaws together define a workbench worksurface.

10. A vice arrangement substantially as hereinbefore described with reference to Figure la and Figures 2, 3 and 4 or Figure lb of the accompanying drawings.