US3283620A

US3283620A - Torque wrench

Info

Publication number: US3283620A
Application number: US503927A
Authority: US
Inventors: Jay R Bailey
Original assignee: Mcculloch Corp
Current assignee: Mcculloch Corp
Priority date: 1965-10-23
Filing date: 1965-10-23
Publication date: 1966-11-08
Anticipated expiration: 1983-11-08

Description

Nov. 8, 1966 J. R. BAILEY 3,283,620

TORQUE WRENCH Filed Oct. 23, 1965 1/0 A. Bailey INVENTOR WHA NN 5 Ma MAN/64L B Al /arms for A yb'am/ United States Patent ()fiice 3,283,620- Patented Nov. 8, 1966 3,283,620 TORQUE WRENCH Jay R. Bailey, Woodland Hills, Ca]if., assignor to McC ulloch Corporation, Los Angeles, Calif., a corporation of Wisconsin Filed Oct. 23, 1965, Ser. No. 503,927 6 Claims. (Cl. 81-524) This invention relates generally to hand tools and relates more particularly to a torque wrench.

In many types of assembly work various parts are secured together by screws and it is very important that these screws are of the proper tightness. If the screws are too loose the parts will not be secured together properly and if they art tightened too much there is danger of stripping the threads of the screws or the tapped openings into which said screws are screwed or driven.

It is therefore an object of the present invention to provide a torque wrench that will overcome the above difficulty.

It is another object of the invention to provide a torque wrench with which the required close control of the tightness of the screws is effected.

It is still another object of the invention to provide a torque wrench of this character calibrated for effecting a desired predetermined tightness of the screws.

It is a further object of the invention to provide a torque wrench of this character which indicates when the predetermined torque level has been reached.

It is a still further object of the invention to provide a torque wrench of this character with which fasteners or screws are uniformly tightened.

Another object of the invention is to provide a device of this character that is extremely simple in construction and that has a minimum number of parts.

Still another object of the invention is to provide a device of this character that is rugged and durable.

It is a further object of the invention to provide a device of this character that may be manufactured at relatively low cost.

The characteristics and advantages of the invention are further sufiiciently referred to in connection with the following detailed description of the accompanying drawings, which represent one embodiment. After considering this example skilled persons will understand that many variations may be made without departing from the principals disclosed and I contemplate the employment of any structures, arrangements or modes of operation that are properly within the scope of the appended claims.

Referring to the drawings, which are for illustrative purposes only:

FIG. 1 is a perspective view of a wrench embodying the present invention;

FIG. 2 is an enlarged top plan view of same with the parts in the normal position; and

FIG. 3 is an enlarged top plan view of the forward end of the wrench with the indicater parts showing that the predetermined torque level has been reached.

Referring more particularly to the drawings, there is shown a wrench embodying the present invention. The wrench is formed of a piece of bar stock and includes a handle 10, at the forward end of which is a U-shaped loop, indicated generally at 11, and extending laterally of the handle. Loop 11 includes an arm 12 that extends at right angles to the forward end of the handle, a closed arcuate end portion 14 that connects the outer end of arm 12 with the outer end of an arm 15 that is substantially parallel to the arm 12, although the arm 12 is inclined downwardly from the portion 14 so that the junction 13 of the arm 12 with the handle is lower than the adjacent end of the arm 15.

From the end of arm 15 opposite the portion 14 which comprises the closed end of the U-shaped part 11, there is a depending part 16 normal to the arm 15 and also normal to the handle 10.

The free end of the depending part 16 is of such shape as to engage the head of a screw 18 for an assembly including the part 20.

The parts of the tool are integral and as shown the tool is of the same cross-sectional shape and size throughout its length. In this case the cross-sectional shape of the tool is hexagonal so that the free end portion of the part 16 is of the proper shape for operable reception in the recess provided in the head of the screw 18 which is hexagonal in cross-sectional shape, said screw 18 being of the Allen type. It is to be understood, of course, that the free end portion of the part 16 may be of other characteristics and the rest of the tool need not be of the same shape and/or size as the free end portion that is engageable with the screws to be tightened.

The stock used for the tool is resilient and the resilient characteristics thereof are of such predetermined value that when a screw is tightened to the desired tightness the closed portion 14 of the wrench deflects and the ends of the

arms

12 and 15 opposite the closed end portion 14 move toward each other. The length of the arm 12 is such that the depending part 16 is in the path of the junction part 13 as the ends of the

arms

12 and 15 opposite the part 14 move toward each other as the screw is tightened and said part 13 closely approaches the part 16, as shown in FIG. 3, or actually engages said part 16 when the screw has been tightened to the desired amount.

The force applied to the handle 10 by the operator is then released,

parts

12 and 16 of the tool returning to their normal positions as shown in FIGS. 1 and 2 and the tool removed from the recess or socket in the head of the screw 18.

As pointed out above, the screw engaging portion of the wrench may be of some other shape and/ or size.

For example, the screw engaging portion of the part 16 may be a blade for reception in the slot of a screw, or it may be a socket for positioning over the head of a screw. The screw-engaging portion of the tool may, of course, be of still other configurations.

The invention and its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of the parts of the invention without departing from the spirit or scope thereof or sacrificing its material advantages, the arrangements hereinbefore described being merely by way of example, and I do not wish to be restricted to the specific forms shown or uses mentioned except as defined in the accompanying claims, wherein various portions have been separated for clarity of reading and not for emphasis.

I claim:

1. In a torque wrench:

(A) a handle;

(B) a laterally extending loop having a pair of arms spaced apart laterally relative to each other, one of said arms having one end connected to the handle and having its other end connected to the adjacent end of the other arm by a resilient portion;

(C) and a screw-engaging part extending from the end of the other arm opposite the part connecting the arms together and normal to the plane of the loop, there being a free end portion of the screw-engaging part adapted to operably engage a screw.

2. The invention defined by claim 1, wherein the tool is formed of a single piece of bar stock.

3. The invention defined by claim 1, wherein the loop is U-shaped and the arms thereof are normally substantially parallel to each other.

4. The invention defined by claim 1, wherein the tool References Cited by the Examiner is formed of bar stock that is hexagonal in cross section. UNITED STATES PATENTS @253 ;gfiffilfiiffifififiii fiahifi f ggggggg ggggg ggg gg 5;;

6. The invention defined by claim 1, wherein the end of 5 the arm connected to the handle and opposite the resilient FOREIGN TENTS portion is inclined in the direction of said screw-engaging 60,530 1/ 1943 Denmark. part, said screw-engaging part being in the path of move- 675,755 5/ 1939 Germany.

rnent of the handle connected end of said arm when the ends of the arms opposite the resilient portion are moved 1O WILLIAM FELDMAN Primary Exammer' together. JAMES L. JONES, J 11., Examiner.

Claims

1. IN A TORQUE WRENCH: (A) A HANDLE; (B) A LATERALLY EXTENDING LOOP HAVING A PAIR OF ARMS SPACED APART LATERALLY RELATIVE TO EACH OTHER, ONE OF SAID ARMS HAVING ONE END CONNECTED TO THE HANDLE AND HAVING ITS OTHER END CONNECTED TO THE ADJACENT END OF THE OTHER ARM BY A RESILIENT PORTION; (C) AND A SCREW-ENGAGING PART EXTENDING FROM THE END OF THE OTHER ARM OPPOSITE THE PART CONNECTING THE ARMS TOGETHER AND NORMAL TO THE PLANE OF THE LOOP, THERE BEING A FREE END PORTION OF THE SCREW-ENGAGING PART ADAPTED TO OPERABLY ENGAGE A SCREW.