GB2140726A

GB2140726A - Adjustable wrench

Info

Publication number: GB2140726A
Application number: GB08312270A
Authority: GB
Inventors: Tien Kuang-Yung
Original assignee: KUANG YUNG TIEN
Current assignee: KUANG YUNG TIEN
Priority date: 1983-05-05
Filing date: 1983-05-05
Publication date: 1984-12-05
Also published as: GB2140726B; GB8312270D0

Abstract

A wrench comprises a fixed jaw (11), a movable jaw, (12) an adjustment screw member (21) for displacing the movable jaw (12) with respect to the fixed jaw (11) and a major handle portion (31), the adjustment screw (21) being hollow and being disposed in a rectangular aperture (25) in the fixed jaw (11), a cotter pin (23) disposed in the hollow interior of the adjustment screw (21), a return spring (22) disposed around the cotter pin (23) and an auxiliary handle portion (32), the auxiliary handle portion (32) being pivotally mounted and having one end portion movable into and out of engagement with the cotter pin (23), the engagement of the end portion with the cotter pin (23) causing axial displacement of the cotter pin (23) and the adjustment screw (21) in the rectangular slot (25) and causing displacement of the movable jaw (12) towards the fixed jaw (11). <IMAGE>

Description

SPECIFICATION Adjustable wrench The present invention relates to a handtool and, more particularly, to a handtool suitable for use in plumbing.

Amongst known tools, a water pump plier is the most commonly used handtool for effect ing plumbing installations and repairs and an adjustable angle wrench is one of the most widespread and common handtools. The angle wrench is generally used to remove and install hexagon-headed bolts or nuts of different sizes. In effecting plumbing repairs, the user usually has to remove or install a water pipe utilising a water pump plier and has to remove or install a bolt or nut using an adjustable angle wrench. The usd of an ad-.

justable angle wrench is disadvantageous because it must repeatedly be disengaged and reapplied to the bolt or nut. This is extremely time-consuming and the tool is often inconvenient for use particularly when removing or installing a bolt or nut in the closed position.

According to the present invention there is provided a wrench comprising a fixed jaw, a movable jaw, an adjustment screw member for displacing the movable jaw with respect to the fixed jaw and a major handle portion, the adjustment screw being hollow and being disposed in a rectangular aperture in the fixed jaw, a cotter pin disposed in the hollow interior of the adjustment screw, a return spring disposed around the cotter pin and an auxiliary handle portion, the auxiliary handle portion being pivotally mounted and having one end portion movable into and out of engagement with the cotter pin, the engagement of the end portion with the cotter pin causing axial displacement of the cotter pin and the adjustment screw in the rectangular slot and causing displacement of the movable jaw towards the fixed jaw.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of an adjustable wrench in accordance with the present invention; Figure 2 is a schematic partial section view of part of the wrench shown in Fig. 1 in a first position of use; Figure 3 is a view similar to Fig. 2 but showing the wrench in a second position of use.

Figure 4 is a view showing the relative dimensions of a hexagon-headed bolt or nut.

Figure 5 shows front and side views of a cotter pin and an auxiliarly handle member forming part of the wrench shown in Fig. 1.

As can be seen in Fig. 1, the overall appearance of a wrench in accordance with the present invention is a hybrid of a conventional adjustable angle wrench and a water pump plier. The adjustable wrench of the present invention has, in common with these known tools, a fixed jaw 11 and a movable jaw 12, the jaw 1 2 being displaceable towards and away from the jaw 1 f by an adjustment screw 21. However, the wrench of the present invention additionally comprises means.for axially displacing the screw 21 in the form of a cotter pin 23 which is displaceable in the screw 21, a compression spring 22, a handle member 31 and an auxiliary handle member 32.

The cotter pin and the auxiliary handle member 32 are shown in Fig. 5. The displaceable cotter pin has a substantially cylindrical major portion which at the one end the adjustment screw has a hollow interior through which the major portion of the cotter pin passes. One end region of the cotter pin is in the form of a cylinder having an increased diameter relative to the major portion. Such end region also carries a rectangular section key. The cotter pin and adjusting screw are located in a rectangular aperture 25 formed in the handle member 31. The dimension of the aperture 25 are selected so that the adjustment screw 21 can be axially displaced therein. Such displacement is effected by utilising the auxiliary handle member 32.Within the aperture 25, a return spring 22 is provided around the cotter pin 23 to cause movement of the adjustment screw in a direction opposite that achieved by utilising the auxiliary handle member 32.

The auxiliary handle member 32 is shown in Fig. 5 and is generally thin and flat. One end thereof contacts the cotter pin 23 and the other end is in the form of a handle which can be depressed or released. The member 32 is pivotally mounted on a center pin 33 which also passes through the handle member 31.

When the handle end of the auxiliary handle is depressed, the other end located within the rectangular hole in the major handle member applies a force to the movable cotter pin and displaces the adjustment screw 21 axially, thereby causing the movable jaw 12 to move towards the fixed jaw 11. When the auxiliary handle member 32 is released, a spring 34 causes the auxiliary handle member 32 to move away from the handle member 31. The force acting on the cotter pin is therefore relieved and the return spring 22 causes the adjustment screw and the movable jaw to return to their original positions. The original positions are shown in Fig. 2 and the positions these members occupy when the auxiliary handle member 32 is depressed are shown in Fig. 3. The adjustment screw can thus be moved axially by applying pressure to the auxiliary handle member or by releasing such member.The auxiliary jaw is, of course, moved the same distance as the adjustment screw. The maximum possible distance of displacement d' is greater than the difference between the diagonal dimension of the nut R and the inter-flat dimension of the nut S, that is to say d' > R-S.

The device of the present invention can thus be used for removing and installing bolts or nuts without having to disengage the tool completely from the bolt or nut until the removal or installation is completed.

The manner of use of the device of the present invention will now be described.

Firstly, the adjustment screw 21 is rotated until the spacing between the fixed jaw 11 and the movable jaw 12 is slightly wider than the diagonal dimension R of the nut or bolt.

The auxiliary handle member 32 is then depressed to cause the displaceable jaw 12 to move towards the fixed jaw 11 and to clamp onto the hexagon head of the bolt or nut. The bolt or nut is then tightened or loosened by rotating the wrench in a conventional manner.

The auxiliary handle 32 is then released. The displaceable jaw 1 2 moves away from the fixed jaw 11 and the wrench can be slid around the exterior of the nut or bolt to engage a second pair of opposed flats of the nut or bolt. This cycle is then repeated. If necessary or desired, the opening between the fixed and movable jaws may be directly adjusted to the size of the nut or bolt to ensure full tightening of the nut or bolt or, alternatively, to effect the initial loosening of the nut or bolt if such is being removed.

This device of the present invention can also be used as a water pump plier which is capable of removing and installing water pipes. The manner of operation of the device under such circumstances is substantially identical to the method of use described hereinbefore.

The device of the present invention therefore combines the functions of an adjustable angle wrench and a water pump plier. The appearance of the device of the present invention is a hybrid of the appearances of a conventional adjustable angle wrench and a water pump plier. The auxiliary handle of the device of the present invention is however shorter than the handle of a conventional water pump plier. The angle between the major handle member 31 of the device of the present invention and the adjustment slot 25 in the fixed jaw is substantially the same as that subtended in a water pump plier, but bigger than that subtended in a conventional adjustable angle wrench.

Claims

1. A wrench comprising a fixed jaw, a movable jaw, an adjustment screw member for displacing the movable jaw with respect to the fixed jaw and a major handle portion, the adjustment screw being hollow and being disposed in a rectangular aperture in the fixed jaw, a cotter pin disposed in the hollow interior of the adjustment screw, a return spring disposed around the cotter pin and an auxiliary handle portion, the auxiliary handle portion being pivotally mounted and having one end portion movable into and out of engagement with the cotter pin, the engagement of the end portion with the cotter pin causing axial displacement of the cotter pin and the adjustment screw in the rectangular slot and causing displacement of the movable jaw towards the fixed jaw.

2. An adjustable wrench as claimed in claim 1, wherein the rectangular aperture in the major handle member has an axial length which is longer than the axial length of the adjustment screw and the maximum distance of displacement of the movable jaw with respect to the fixed jaw by actuating said auxiliary handle member being so selected as to exceed the difference in the diameters of a nut or bolt between opposed vertices and opposed flats.

3. An adjustable wrench as claimed in claim 1 or 2 wherein the auxiliary handle member is thin and flat and has a first end region locatable in region of the rectangular aperture in the major handle member, the auxiliary handle member being in the form of a handle which can be depressed or released.

4. An adjustable wrench as claimed in claim 1 constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.