IL148435A - Adjustable clamp and release mechanism therefor - Google Patents

Description

may *mn¾> tynYi nn nan a ADJUSTABLE CLAMP AND RELEASE MECHANISM THEREFOR 1158TEF-IL 1158tef.doc 18-Feb-02 ADJUSTABLE CLAMP AND RELEASE MECHANISM THEREFOR FIELD OF THE INVENTION The present invention relates generally to adjustable clamps, and particularly to a release mechanism for releasing a ratchet mechanism of an adjustable clamp.

BACKGROUND OF THE INVENTION There are many kinds of clamps used to grip objects. One kind of clamp, often referred to as a spring clamp, is provided with a spring that forces the jaws of the clamp towards one another. In order to use a spring clamp, one squeezes the handles of the clamp together, wherein the squeezing action works against the force of the spring, thereby spreading the clamp jaws apart and permitting insertion of a workpiece or workpieces between the jaws. Upon release of the squeezing force, the spring forces the jaws against the workpiece or workpieces.

A variation of the spring clamp is known as an adjustable clamp. In an adjustable clamp, a spring is provided that forces the jaws of the clamp away from one another. When a user squeezes the handles of the adjustable clamp towards one another, the clamp jaws are gradually brought closer to one another until they finally abut each other. A ratchet mechanism is provided that works against the force of the spring and arrests the clamping jaws at discrete positions as they approach one another. The ratchet mechanism thus permits adjusting and maintaining the clamping jaws at any desired position as the handles of the adjustable clamp are squeezed together. In this manner, the jaws may be clamped against a workpiece or workpieces placed between the jaws.

A release mechanism is provided for releasing the ratchet mechanism of the adjustable clamp. In the prior art, the release mechanism is typically some kind of button, which when pressed, releases a tooth of the ratchet mechanism and permits the spring to force the clamping jaws away from each other.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved adjustable clamp. Moreover, the present invention seeks to provide an improved release mechanism for releasing a ratchet mechanism of an adjustable clamp. The release mechanism of the present invention is preferably completely symmetrical for right-handed and left-handed users of the clamp. Unlike the prior art, the release mechanism of the invention straddles and extends beyond one or both sides of one of the handles of the adjustable clamp and is significantly more convenient to use than prior art clamps.

There is thus provided in accordance with a preferred embodiment of the present invention an adjustable clamp including a pair of handles pivoted about a pivot, a pair of clamping arms extending from the handles, a clamping jaw attached to each of the clamping arms, a spring mounted in juxtaposition with the pivot, and adapted to force the clamping jaws away from one another, a ratchet mechanism adapted to arrest the clamping jaws at a plurality of positions with respect to one another, and a release mechanism mounted on one of the handles and adapted to disengage the ratchet mechanism, the release mechanism including a release knob that straddles and extends beyond at least one side (preferably both sides) of that handle.

In accordance with a preferred embodiment of the present invention the ratchet mechanism includes a ratchet rack formed with a plurality of teeth, and a pawl arranged to engage at least one of the teeth.

Further in accordance with a preferred embodiment of the present invention the release mechanism is adapted to disengage the pawl from the teeth of the ratchet rack.

Still further in accordance with a preferred embodiment of the present invention the clamping jaws are pivotally attached to the clamping arms.

Additionally in accordance with a preferred embodiment of the present invention the release knob includes a tail member that extends at angle away from the pawl.

In accordance with a preferred embodiment of the present invention the tail member is biased against a spring which urges the release knob and the pawl against the teeth of the ratchet rack.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood and appreciated more fully from the following detailed description taken in conjunction with the drawings in which: Fig. 1 is a simplified pictorial illustration of an adjustable clamp, constructed and operative in accordance with a preferred embodiment of the present invention, in a closed position; Fig. 2 is a simplified pictorial illustration of a ratchet mechanism and a release mechanism for the adjustable clamp of Fig. 1, constructed and operative in accordance with a preferred embodiment of the present invention; Fig. 3 is a simplified pictorial illustration of the adjustable clamp of Fig. 1 , in accordance with a preferred embodiment of the present invention, in an open, released position; and Fig. 4 is a simplified top view illustration of the adjustable clamp of Fig. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is now made to Figs. 1 and 3, which illustrate an adjustable clamp 10, constructed and operative in accordance with a preferred embodiment of the present invention.

Adjustable clamp 10 preferably comprises a pair of handles 12 that are pivoted about a pivot 14. A pair of clamping arms 16 preferably extend from handles 12. Each clamping arm 16 preferably comprises a clamping jaw 18 attached thereto. Clamping jaw 18 may be pivotally attached to clamping arm 16. A spring 20 (seen in Figs. 2 and 3) is preferably mounted in juxtaposition with pivot 14 that forces the clamping jaws 18 away from one another in the direction of arrows 21 in Fig. 3.

A ratchet mechanism 22 is preferably provided that works against the force of spring 20 and arrests clamping jaws 18 at plurality of positions as they approach one another. Ratchet mechanism 22 may comprise an arcuate ratchet rack 24 formed with a plurality of teeth 26. A pawl 28 is preferably arranged to engage one or more of the teeth 26. When pawl 28 engages teeth 26, the ratchet mechanism 22 works against the force of spring 20 and arrests the clamping arms 16 and clamping jaws 18 at discrete positions (e.g., defined by the pitch of teeth 26) as they approach one another. In this manner, clamping jaws 18 may be clamped against a workpiece or workpieces (not shown) placed between clamping jaws 18.

A release mechanism 30 is preferably provided for releasing ratchet mechanism 22. Specifically, the release mechanism 30 may disengage pawl 28 from the teeth 26 of ratchet rack 24. Release mechanism 30 preferably includes a release knob 32 attached to pawl 28 and which pivots about a pivot 34. Release knob 32 may be manufactured separately from pawl 28 and secured to pawl 28. Alternatively, release knob 32 may be an integral part of pawl 28, such as a one-piece injection molded part, for example. Release knob 32 preferably includes a tail member 36, which may extend at angle away from pawl 28. The tail member 36 is preferably biased against a spring 38. Spring 38 preferably urges release knob 32, and thus pawl 28, against the teeth 26 of ratchet rack 24, in a direction indicated by arrow 40. Accordingly, as long as release mechanism 30 is not actuated, spring 38 ensures that pawl 28 engages ratchet rack 24 and arrests the clamping arms 16 and clamping jaws 18 at a selected position for clamping an object or objects therebetween.

Release mechanism 30 may be easily actuated by pivoting release knob 32 about pivot 34 in a direction indicated by arrow 42. This action releases pawl 28 from the teeth 26 of ratchet rack 24. Once pawl 28 no longer engages ratchet rack 24, spring 20 forces the clamping jaws 18 away from one another in the direction of arrows 21 in Fig. 3.

Release knob 32 preferably straddles and extends beyond at least one of the sides of one of the handles 12, as seen best in Fig. 4. Release knob 32 preferably straddles and extends beyond both sides of the handle 12. Release knob 32 and release mechanism 30 are easily accessible, and are preferably completely symmetrical, for right-handed and left-handed users of adjustable clamp 10.

It will be appreciated by person skilled in the art that the present invention is not limited by what has been particularly shown and described herein above. Rather the scope of the present invention is defined only by the claims that follow:

Claims (9)

CLAIMS What is claimed is:

1. An adjustable clamp comprising: a pair of handles pivoted about a pivot; a pair of clamping arms extending from said handles; a clamping jaw attached to each of said clamping arms; a spring mounted in juxtaposition with said pivot, and adapted to force said clamping jaws away from one another; a ratchet mechanism adapted to arrest said clamping jaws at a plurality of positions with respect to one another; and a release mechanism mounted on one of said handles and adapted to disengage said ratchet mechanism, said release mechanism comprising a release knob that straddles and extends beyond at least one side of said one of said handles.

2. The adjustable clamp according to claim 1 wherein said ratchet mechanism comprises a ratchet rack formed with a plurality of teeth, and a pawl arranged to engage at least one of said teeth.

3. The adjustable clamp according to claim 2 wherein said release mechanism is adapted to disengage said pawl from said teeth of said ratchet rack.

4. The adjustable clamp according to any of the preceding claims wherein said clamping jaws are pivotally attached to said clamping arms.

5. The adjustable clamp according to claim 2 or claim 3 wherein said release knob comprises a tail member that extends at angle away from said pawl.

6. The adjustable clamp according to claim 5 wherein said tail member is biased against a spring which urges said release knob and said pawl against said teeth of said ratchet rack.

7. The adjustable clamp according to any of the preceding claims wherein said release knob straddles and extends beyond both sides of said one of said handles.

8. The adjustable clamp according to any of the preceding claims wherein said release knob is symmetrical for a right-handed user and a left-handed user of said adjustable clamp.

9. The adjustable clamp according to any of the preceding claims and substantially as shown and described hereinabove. licant, David Klein, Patent Attorney Dekel Patent Ltd.