AU645499B2

AU645499B2 - Rapid jaw adjustment for tools and the like

Info

Publication number: AU645499B2
Application number: AU59179/90A
Authority: AU
Inventors: Ralph Petersen
Original assignee: Petersen Manufacturing Co Inc
Current assignee: Petersen Manufacturing Co Inc
Priority date: 1989-08-11
Filing date: 1990-07-23
Publication date: 1994-01-20
Anticipated expiration: 2010-07-23
Also published as: NL9001789A; DE4024999A1; CN1049306A; SE9002366D0; BR9003958A; DK176990D0; GB2234701A; GB9015370D0; BE1003467A4; IT1246418B; FR2650774A1; KR910004310A; JPH0398771A; HK25394A; IT9021166A0; AU5917990A; GB2234701B; SE9002366L; IT9021166A1; CA2022519A1

Description

64599

RALIA

Patents Act 1952 COMPLETE SPECIFICATION r *1 r S. j" Applicant: PETERSEN MANUFACTURING CO., INC.

Address DeWitt, Nebraska 68341, USA Address for Service: Chrysiliou Moore Chrysiliou P.O. Box 373 Collaroy Beach NSW 2097 Complete Specification for an invention entitled: "RAPID JAW ADJUSTMENT FOR TOOLS AND THE LIKE" The following statement is a full description of this invention, including the best method of performing it known to me:

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RAPID JAW ADJUSTMENT FOR TOOLS AND THE LIKE Background of The Invention This invention relates to hand tools, and more particularly to tools utilizing a pair of jaws for receiving a workpiece therebetween.

Common elements of locking pliers, locking wrenches and '"'similar tools employing some form of locking toggle-actuation are ;a pair of stationary and movable jaws adapted to lock a workpiece therebetween. A mechanism with an adjusting element acting on the movable jaw is usually provided to adjust a gap between the jaws and to bring them into possible initial contact with a workpiece

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before huge forces of the toggle action are generated and applied.

The tools of the type presently described are usually used in the circumstances when fast and efficient adjustment of the gap between the jaws is not only highly desirable but absolutely necessary. One example of such use is a conveyor welding operation where a welder has a very short time for adjustment of the tool between welding together two separate pairs of elements having different dimensions. In this situation, it is extremely important to adjust the gap between the jaws of the locking tool to -Ibaccommodate the dimensions of a new pair of elements as soon as possible.

A known type of prior art device makes such adjustment of a gap between the jaws by means of rotation of a single threaded, single pitch adjustment screw to which the movable jaw is connected directly or indirectly. This method and means of adjustment are necessarily slow and time consuming and result in loss of valuable time in adjusting the tools from one size to another.

Accordingly, the present invention provides a hand tool comprising a fixed handle; a movable handle connected to a movable jaw; a screw member rngageable with the receiving portion; toggle means defined by at least one toggle S" member having first and second ends, the first end being pivotally secured to the movable handle and the second end adapted to be contacted by an end of the screw member to adjust position of the movable jaw relative to the fixed jaw; characterised in that the screw member has a plurality of first individual and separate threads 20 extending along a longitudinal axis thereof and further characterised in that the threaded opening of the receiving portion has a plurality of second individuai and separate threads adapted for threadable engagement with the plurality of the first threads of the screw member, whereby one turn rotation of the screw member within the threaded opening results in advancement of the screw -Icmember in the longitudinal axial direct substantially equal to a combined pitch of the plurality of first threads.

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e 9 o* 6deccmmdate the ~,mznccion- -a nw- pa-r-e-f-el-emes--as-oseo-apossible.

A known type of prior art device makes such adjustment of a gap between the jaws by means of rotation of a single threaded, single pitch adjustment scre -to which the movable jaw is connected directly or indire my. This method and means of adjustment are necessar slow and time consuming and result in loss of valuable tOe-in adjutng tho tool .sSom-Qowasize to ano ther.

Brief Description of The drawings Other advantages and features of the invention are described with reference to exemplary embodiments, which are intended to explain and not to limit the invention, and are illustrated in the drawings in which: Fig. 1 is a side view of long-nose pliers utilizing the invention.

S Fig. 2 is a side, partial cross-section view of pliers having curved jaws and utilizing the invention.

Fig. 3 is a partially, enlarged view of a threaded arrangement ,,shown in Figs. 1 and 2.

Fig. 4 is an end view of a screw member.

Fig. 5 is a partial cross-section view of threads of the screw member.

Fig. 6 shows a partial view of a toggle-locking C-clamp.

Fig. 7 is a perspective view of a locking chain clamp.

Fig. 8 is a perspective view of a locking welding clamp.

Fig. 9 is a perspective view of a sheet metal tool.

Description Of The Preferred Embodiment Although a specific embodiment of the invention will now be described with reference to the drawings, it should be understood that the embodiment shown is by way of example only and merely illustrative of but one of the many possible specific embodiments which can represent applications 'of the principles of the invention. Various changes and modifications, obvious to one skilled in the art to which the invention pertains, are deemed to be within the spirit, scope and contemplation of the invention as further defined in the appended claims.

As best shown in Fig. 1, the long-nose locking pliers is

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'...generally designated by the reference numeral 10, and includes a 0 ""'"handle member 12, and a movable clamping member or lower jaw 14.

The handle member 12 is provided with a stationary clamping element *or upper jaw 16. A toggle mechanism comprises an elongated handle member 18 and a toggle-link member 20 which is conventionally pivotally engaged at one end about the pin 22. The other free end S(shown in phantom) of the toggle link member 20 is engaged with the handle member 12, and in particular the abutment end (also shown phantom) of an adjustment screw member 24 which is suitably threadably engaged at the end of the handle member 12. Operation the screw member will be discussed in full detail later in this 0 **'.,application. The forward end of the handle member 18 is preferably bifurcated or forked, and a corner portion of the movable clamping member 14 is suitably disposed within the fork or between the bifurcation arms by pivot pin means 19. Similarly, the handle member 12 is preferably channel-shaped, and receives another corner portion of the movable clamping element 14 which is also suitably secured thereto by means of a pivot pin 17.

Spring means 25, preferably in the form of an extension coil spring, is secured between the handle member 12 and the movable clamping element 14 or lower jaw, to urge the clamping element 14 away from the stationary clamping element when the jaws are opened.

An elongated release lever 28 is suitably pivotally mounted by means of a pin 30, to the inside of the handle member 18, and is provided with a forwardly extending portion (as shown in phantom) and is engageable with a projection 32 of the toggle-like member 20 which extends toward the handle member 18. When the *too release lever 28 is pivoted about the pin 30, the handle member 12 is moved away from the handle member 18.

It will be appreciated that the wrench or locking pliers mechanism and toggle construction described herein, with some exceptions, conforms basically in accordance with the construction described in U.S. Patent No. 1,489,458. Furthermore, such construction, the operation thereof, and the specific operation of the release lever is clearly set forth in U.S. Patent No.

3,192,804. As explained in these Petersen prior art patents, closing of a locking wrench or pliers incorporating a toggle device is effected by moving the relatively movable handle member 18 toward the relatively fixed handle member 12. This movement forces the upper end of the toggle-like member 20 to move inwardly towards the handle member 12. The pivot pin 22 also moves inwardly, and when such pivot pin moves over center, the pliers is locked in a closed position.

A tool of a further embodiment of the invention is best in coYlC.n-inrio wi4 Fi3. 3, illustrated in Fig. 2 and includes a fixed arm 15 having a fixed handle 12 at one end and a fixed jaw 16 at the other end. A movable jaw 14 is pivotally attached to a movable handle member 18.

The jaws 14 and 16, shown in Fig. 2, are curved and bulky. A toggle-link member 20 is pivotally engaged with the movable handle.

:The other free end 44 of the toggle-link engages with a contacting "part of a screw member 24. The fixed handle is suitably formed as 3o0 f fied hanodle i.e *a U-shaped channel. The end of the fi._xd ha.dl- 30, remote from

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'the fixed jaw 16, is completed with a receiving portion 32 having L:ov Pt*y ctr.d rear prp-- 31, front 3- and r 36 part:. A threaded opening 38 extends through the receiving portion from the part 34 to part 36. A screw member 24 is provided for threadable engagement with the threaded opening.

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The screw terminates in a knurled adjusting knob 40 at one end and the contacting part 42 at the other end.

When the screw merber 24 is turned at the knob by the user, its rotation within the threaded opening results in advancement of *the screw in the axial direction. Such advancement in the .:direction of the fixed jaw 16 presses the contacting part 42 against the toggle-link 20 and changes the distance between the end ii I~ap~l u; i of the toggle link 44 from the pivot point 17 of the movable jaw 16, whereby the distance between the stationary jaw 16 and the movable jaw 14 is adjusted to grip objects of different dimensions without exerting excessive force.

The screw member 24 and the threaded opening 38 are illustrated in better detail in Fig. 3. A combined threaded part 44 of the screw member consists of two individual, separate and coaxial threads 46 and 48 extending along a longitudinal axis A-A.

However, the screw member having any reasonable number of individual threads is within the scope of the invention.

Since the pitches of the threads 46 and 48 shown in Figs. 3are identical, the distance between corresponding points on :.adjacent turns of the thread 46 is equal to the distance between corresponding points on adjacent turns of the thread 48.

Fig. 5 further illustrates that the crest and root diameters both threads are essentially the same.

To provide adequate threadable engagement between the screw member 24 and the opening 38, the latter has a combined internal thread consisting of two individual, separate and coaxial threads 50 and 52 adapted to threadably engage with the threads 46 and 48 *9* 2..of the screw member. The internal individual threads 50 and 52 extend through the length of the opening 38 from the front part of the receiving portion 34 to the rear part 36.

S In the preferred embodiment of the invention illustrated in Fig. 4, two different starting points 54 and 56, at a specific angle apart, are provided for the individual threads of the screw

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member. This is also applicable to the threaded opening. Although such angle between two starting points could be of any reasonable value, Fig. 4 illustrating an end view of the screw member of the preferred embodiment shows such angle equal 1800.

If the screw member is pLovided with three individual threads the angle between adjacent starting points could be 1200.

In order to prevent false starts when turning the screw member into the threaded opening, an alternative embodiment (not shown on the drawings) having a single initial or run-on turn is contemplated by the invention. Thus, one thread of the screw member makes initial mating engagement with the corresponding thread of the threaded opening at the beginning of the initial or run-on thread turn of the threaded engagement. Similarly, the second thread of the screw member makes initial mating engagement with the corresponding thread on the threaded opening at the a o beginning of the same initial or run-on turn. Therefore, only one Sstarting point for two threads is provided in such alternative embodiment.

The threads of the invention could be metric as well as U.S.

*too it, Standard threads.

When a single threaded engagement between the screw member and the threaded opening is used, as disclosed by the prior art, the distance which the screw advances axially on one turn of the knob is equal to the pitch of the single thread. On the contrary, if the multiple threaded screw is used, as provided by the invention, the axial advancemant of the screw on one turn of the knob is equal to a combined pitch of all individual threads used. The screw member 24 has two individual threads 46 and 48 having corresponding pitches P1 and P2. When the user rotates the knob 40 one full turn, the advancement of the screw in the axial direction is equal to a combined pitch P1 and P2. Such double advancement by the screw acting on the toggle link substantially increases the rate of adjustment of the movable jaw relative to the stationary jaw.

Fig. 6 illustrates the a-ms of a toggle-locking C-clamp wherein a fixed clamp member 51 is shown cooperating with a movable clamp member 52, which pivots about the pin 53.

Fig. 7 shows a locking chain clamp, Fig. 8 shows a locking welding chain and Fig. 9 illustrates a conventional sheet metal :tool. All tools are well-known in the art and are incorporated by reference.

The above-described arrangements for increasing the rate c adjustment of the movable jaws or similar movable part can be applied to the tools shown in Figs. 6-9.

The adjustment screw arrangement described hereinabove is also applicable for Stilson wrenches, bench vises and other types of tools.

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Claims

1. A hand tool comprising: a fixed handle having a fixed jaw and a receiving portion defined by a threaded opening situated within the fixed handle; a movable handle connected to a movable jaw; a screw member engageable with the receiving portion; toggle means defined by at least one toggle member having first and second ends, the first end being pivotally secured 10 to the movable handle and the second end adapted to be contacted by an end of the screw member to adjust position of the movable jaw relative to the fixed jaw; characterised in that the screw member has a plurality of first individual and separate threads extending along a 15 longitudinal axis thereof and further characterised in that the threaded opening of the receiving portion has a I plurality of second individual and separate threads adapted for threadable engagement with the plurality of the first threads of the screw member, whereby one turn rotation of the screw member within the threaded opening results in advancement of the screw member in the longitudinal axial direction substantially equal to a combined pitch of the plurality of first threads. AL/

2. A hand tool as claimed in claim 1, wherein the threads Sp have identical pitches.

3, A hand tool as claimed in claim 2, wherein the pitches are U S standard pitch 14.

4. A hand tool as claimed in any one of claims 1 to 3, wherein the plurality of second individual and separate threads extend through the entire length of the threaded opening.

A hand tool as claimed in any one of claims 1 to 4, wherein the threads are metric standard threads. 'I

6. A hand tool as claimed in any one of claims 1 to 4, wherein the threads are U S standard threads.

7 A hand tool as claimed in claim 6, wherein the threads are U S standard thread 6/16-18 UNC-2A.

8. A hand tool as claimed in any one of claims 1 to 7, wherein the hand tool is a locking hand tool.

9. A hand tool as claimed in any o.ne of claims 1 to 8, wherein the threads have starting points positioned within the same plane, perpendicular to the longitudinal axis of the screw, the starting points being at an angle to each other.

10. A hand tool as claimed in any one of claims 1 to 9, wherein the screw member has two individual and separate threads and the threaded opening has two individual and separate threads. nf

11. A hand tool as claimed in claim 10, wherein the angle -11- between the starting points is 180 degrees.

12. A hand tool substantially as described herein with reference to any one of Figures 1, 2, 6, 7, 8 or 9, combined with Figure-! 3 to Dated this eleventh day of November, 1993 PETERSEN MANUFACTURING CO., INC By its Patent Attorney KERRY MOORE CHRYSILIOU of CHRYSILIOU MOORE CHRYSILIOU V,.