EP1225009A1

EP1225009A1 - Adjustable wrench

Info

Publication number: EP1225009A1
Application number: EP01101375A
Authority: EP
Inventors: Arthur Wu
Original assignee: Proxene Tools Co Ltd
Current assignee: Proxene Tools Co Ltd
Priority date: 2001-01-22
Filing date: 2001-01-22
Publication date: 2002-07-24

Abstract

An adjustable wrench includes an elongated wrench body, the wrench body having a fixed jaw at one end thereof, a movable jaw coupled to the wrench body and moved relative to the fixed jaw, the movable jaw having a rack at one side thereof, a worm mounted in the wrench body and engaged with the rack of the movable jaw for rotation by hand to move the movable jaw relative to the fixed jaw, a elastic member mounted in the wrench body and supported between the movable jaw and the wrench body to force the movable jaw in direction apart from the fixed jaw for forcing the teeth of the rack of the movable jaw to attach on the teeth of the worm.

Description

BACKGROUND OF THE INVENTION

The present invention relates to adjustable wrenches and, more particularly, to an improved structure of an adjustable wrench with a movable jaw positioning mechanism.
In conventional adjustable wrenches, a worm is used for rotating by the thumb to move a movable jaw relative to a fixed jaw. However, because a clearance of teeth is left between the teeth of rack of the movable jaw and the teeth of the worm, the jaw tends to displace or wobble after each adjustment, causing a variation of the distance between the fixed jaw and the movable jaw.
In the adjustable wrench of US #5,644,957, a locking disc is provided at one end of the worm to attach with a cam surface on the wrench body. After adjustment, the locking disk is rotated an angle and forced into engagement with one rack tooth of the movable jaw to lock the movable jaw. When rotating the locking disk in the reversed direction, the movable jaw is unlocked. This movable jaw locking structure is complicated and expensive. Further, when locking or unlocking the movable jaw, the user must operate the locking disk.
US #5,799,550 discloses another structure of adjustable wrench, in which a screw rod and a nut are provided. When rotating the nut in one direction, the screw rod is lifted and pressed on the movable jaw to hold the movable jaw in position. The procedure of locking the movable jaw is also complicated.

SUMMARY OF THE INVENTION

The present invention has been accomplished to provide.an adjustable wrench, which eliminates the drawbacks of the aforesaid prior art adjustable wrenches. It is one object of the present invention to provide an adjustable wrench, which has a simple structure. It is another object of the present invention to provide an adjustable wrench, which automatically holds down the movable jaw in position after each adjustment.
To achieve these and other objects of the present invention, an adjustable wrench is provided comprised of an elongated wrench body, which has a fixed jaw at one end thereof, a movable jaw is slidably coupled to the wrench body and moved relative to the fixed jaw, the movable jaw having a rack at one side thereof, a worm mounted in the wrench body and engaged with the rack of the movable jaw for rotation by hand to move the movable jaw relative to the fixed jaw, an elastic member mounted in the wrench body and between the movable jaw and the wrench body and adapted to force the movable jaw in direction apart from the fixed jaw against the thread of the worm.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded of an adjustable wrench according to a first embodiment of the present invention.
FIG. 2 is a sectional assembly view of the adjustable wrench according to the present invention.
FIG. 3 is a local sectional assembly view shown the distribution of the force the elastic member.
FIG. 4 is a sectional assembly view of an adjustable wrench according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, an adjustable wrench 1 in accordance with the present invention comprises a wrench body 10, a movable jaw 20, a worm 30, and a elastic member 32.
The wrench body 10 has a fixed jaw 11 at its one end, a transverse slot 12 extended sideways from the bottom side of the fixed jaw 11, and an opening 13 disposed below the slot 12.
The movable jaw 20 comprises a slider 22 received in the slot 12 for enabling the movable jaw 20 to be moved along the slot 12, and a rack 23 integral with the bottom side of the slider 22. The worm 30 is pivotally (rotatably) mounted in the opening 13 of the wrench body 10 by a screw pin 31. The spring 32 is mounted on the right end of the worm 30 (directed to the fixed jaw 11) to force the worm 30 against the left side wall of the opening 13. The worm 30 is engaged with the rack 23 of the movable jaw 20. When rotating the worm 30 for example with the thumb, the movable jaw 20 is moved along the slot 12 toward/apart from the fixed jaw 11.
The characteristics of the present invention are outlined hereinafter.
The adjustable wrench 1 further comprises a cylindrical locating block 14, and a elastic member 40. The locating block 14 has an outer thread 141, and a recessed slot 142. The wrench body 10 comprises a receiving hole 15 disposed at one end of the slot 12 of the wrench body 10, which is below the fixed jaw 11. The receiving hole 15 has an inner thread 151. The outer thread 141 of the locating block 14 is threaded into the inner thread 151 of the receiving hole 15, keeping the recessed slot 142 aimed at the slot 12. An elastic member 40 is, which is a compression spring in the present invention, mounted in the slot 12 of the wrench body 10, having one end engaged into the recessed slot (or recess) 142 of the locating block 14 and an opposite end engaged into a recessed slot (or recess) 222, which is provided on the right end of the sliding block 22 of the movable jaw 20. As illustrated in FIG. 3, the elastic member 40 imparts a spring force F on the movable jaw 20 in the direction of apart from the fixed jaw 11, and the spring force F is distributed over the teeth of the rack 23 of the movable jaw 20 with force f, to force them positive attaching with the teeth of the worm 30 for eliminating the clearance of teeth between the worm 30 and the rack 23 of the movable jaw 20 to hold down the movable jaw 20 at the position of user desired.
The use of the adjustable wrench of the present invention is same as the conventional adjustable wrenches. When rotating the worm 30, the movable jaw 20 is moved along the slot 12 relative to the fixed jaw 11. Because of the effect of the elastic member 40, the teeth of the rack 23 of the movable jaw 20 is pressed to attach on the teeth of the worm 30 during any position of the movable jaw 20 has been adjusted, therefore the movable jaw 20 is forced to hold down the movable jaw 20 automatically in any time and any position to prevent axial wobbling of the movable jaw 20 when the user releases the thumb from the worm 30.
FIG. 4 shows a second embodiment of the adjustable wrench of the present invention. According to this alternate form, the adjustable wrench 2 is comprised of a wrench body 50 with a fixed jaw 51 and a recess 54, a transverse slot 52 and an opening 53, a movable jaw 60 with a sliding block 62, a rack 63 and a recessed slot (or recess) 64 on one end of the sliding block 62 in line with the recess 54, a worm 70, and a elastic member 80. The slot 52 does not pierce through the wrench body 50, i.e., the right end of the slot 52 has a closed end and disposed the recessed slot 54 on the inner side of the closed end of the slot 52, which receives the one end of the elastic member 80.
The advantages of the present invention are, first, it doesn't need to change the structure of the wrench wildly, but still provide a good function of positioning the movable jaw. Second, the precedure of operating the adjustable wrench is same as the prior art. It's need no another locking procedure, the adjustable wrench of present invention has the capacity of automatically positioning the movable jaw in any time and any status.
While only two embodiments of the present invention have been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed.
An adjustable wrench includes an elongated wrench body, the wrench body having a fixed jaw at one end thereof, a movable jaw coupled to the wrench body and moved relative to the fixed jaw, the movable jaw having a rack at one side thereof, a worm mounted in the wrench body and engaged with the rack of the movable jaw for rotation by hand to move the movable jaw relative to the fixed jaw, a elastic member mounted in the wrench body and supported between the movable jaw and the wrench body to force the movable jaw in direction apart from the fixed jaw for forcing the teeth of the rack of the movable jaw to attach on the teeth of the worm.

Claims

An adjustable wrench comprising:

an elongated wrench body (10, 50), said wrench body (10,50) comprising a fixed jaw (11,51) at one end thereof;

a movable jaw (20,60) slidable coupled to said wrench body (10,50) and moved relative to said fixed jaw (11,51), said movable jaw (20,60) having a rack (23,63) at one side thereof; and

a worm (30,70) mounted on said wrench body (10,50) and engaged with said rack (23,63) of said movable jaw (20,60) for rotation by hand to move said movable jaw (20,60) relative to said fixed jaw (11,51), characterized by

a elastic member (40,80) supported between said movable jaw (20,60) and said wrench body (10,50); said elastic member (40,80) provides a force on said movable jaw (20, 60) in the direction of apart from said fixed jaw (11,51) for forcing the teeth of said rack (23,63) of said movable jaw (20,60) to attach on the teeth of said worm (30,70) for preventing said movable jaw (20,60) axial wobbling after each adjustment.
The adjustable wrench of claim 1, characterized in that, said wrench body (10,50) comprises a slot (12,52) extended sideways from said fixed jaw (11,51), said movable jaw (20,60) comprises a sliding block (22,62) coupled to and moved with said movable rack (23,63) in said slot (12,52), and said elastic member (40,80) is mounted in said slot (12,52) and against said sliding block (22,62) of said movable jaw (20,60).
The adjustable wrench of claim 2 characterized by a locating block (14) fastened to one end of said slot (12) and against one end of said elastic member (40).
The adjustable wrench of claim 3, characterized in that said wrench body (10) comprises an inner thread (151) disposed at one end of said slot (12), and said locating block (14) comprises an outer thread (141) threaded into the inner thread (151) of said wrench body (10).
The adjustable wrench of claim 3, characterized in that said locating block (14) comprises a recess (142) disposed at an inner end thereof and adapted to receive one end of said elastic member (40).
The adjustable wrench of claim 2, characterized in that said slot (52) has one end (54) closed for against one end of said elastic member (80).
The adjustable wrench of claim 1, characterized in that said movable jaw (20,60) has a recess (222,64) for receiving one end of said elastic member (40,80).
The adjustable wrench of claim 1, characterized in that said wrench body (10,50) has a recess (54) for receiving one end of said elastic member (80).
The adjustable wrench of claim 1, characterized in that said elastic member (40,80) is a compression spring.