US1735257A - Wrench - Google Patents

Description

Nov. 12, 1929.

H. A. MEAD WRENCH Filed May 16. 1929 INVENTOR ,hifLMeaaL QMMgQJJAI;

ATTORNEY Patented Nov. 12, 1929 UNITED STATES PATENT OFFICE HOMER A. HEAD, OF TURLQCK, CALIFORNIA, ASSIGNOR T0 MASTEBE'NOE CORPORA- TION, OF TURLOCK, CALIFORNIA, A CORPORATION WRENCH Application filed May 16, 1929. Serial No. 383,426.

This invention relates to improvements in wrenches and particularly to one of that type having a fixed jaw and handle unit and a movable jaw pivoted in connection 6 with the fixed jaw, and such as is shown in Patent No. 1,533,602 dated April 14th, 1925, and Patent No. 1,63%,908, dated July 5th, 1927, and issued to myself and E. E. Lynch.

In both these previous devices a spring was employed to return the movable jaw to a closed position adjacent the fixed jaw. These springs are so arranged however that in the wrench of the first mentioned patent, if the movable jaw was turned to a full open position, the sprin would disengage the lug provided on the aw and the spring would then be so positioned as to prevent the ready return of said jaw to its closed position.

In the structure of the second mentioned patent the movable jaw could be fully opened and again closed but the spring when fully open would then be engaged at such a point in its length as to make it hard for the operator to move the jaw to such position.

The main object of the present invention therefore is to avoid the objectionable fea tures of construction of the previous devices by arranging the spring in connection with a specially formed engaging surface provided therefor on the movable aw in such a manner that regardless of the extent of opening of said jaw the spring would contact with said surface at substantially a constant point in the length of the spring at any position of the jaw.

The above object is carried out by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

wrench partly broken out showing the movable jaw closed.

Fig. 2 is a similar v1ew show ng the movable jaw in its fully open posltion.

Referring now more particularly to the characters of reference on the drawings, the

Fig. 1 is a side elevation of my improved.

numeral 1 denotes the body or shank of the wrench having a handle 2 on one end of the same and a fixed aw portion 3 on the other end; these elements being a one-piece rigid uni A longitudinal slot 4 is formed in said unit between the jaw and handle and terminates at onaend adjacent said jaw. Projecting into this slot is the shank 5 of the relatively movable aw 6 which is disposed outwardly of the shank 1 and the fixed jaw; a ivot pin 7 being passed through theshanEs to mount the movable jaw in place for movement in a definite lane relative to the fixed aw. The movab e jaw is wider than its shank and is formed with side shoulders 8 at its unction with its shank, which shoulders are adapted when the jaw is swung to a fully open position to then aline with and abut against the edges of the shank 1, as in Fig. 2. The total movement of the movable jaw from its fully closed to its fully open position is approximately 90. The face of the'movable jaw which faces the shank 1 and the fixed jaw is so shaped, and the correspondin edges of the shank 1 on each side of the s ot are also so formed or shaped relative to the jaw face as shown at 9, that when the movable jaw is in a fully open or spread position, said faces 9 will closely follow and engage four sides of a hexagonal nut N. The portion of the shank 1 which has said nut engaging faces formed therein may also therefore be considered as a portion of the fixed jaw. With a lesser extent of opening of the movable jaw the nut engaging faces thereof cooperate only with the outer curved surface of the jaw 3 beyond the slotto hold a relatively small nut as indicated in dotted lines in Fig. 1. Thus far the structure is substantially the same as shown in the previous devices already patented.

A flat spring 10 is fastened at one end to the shank 1 at the handle end of the slot 4 and on the same side or ed e of said shank as that from which the mova le jaw rojects. This spring projects through the slot uetween the ad acent end of the slot and the back edge of the movable shank and at its free end enment the compressive pressure is applied to the spring only at its most flexible oint at all times, and not at a point approac 'ng its fixed end aswas the case with the device shown in Patent No. 1,634,908 especially. Also the provision of the continuous spring engaging cam avoids the movable jaw then being prevented from returning of itself, or with the aid of the spring action, to its closed position as was the case with the structure shown in PatentNo. 1 533,602. 7 v

To further insure the engagement of the sprin with the cam only at all times and 'not with the edge of the jaw beyond the cam (which must b ge outwardly as shown at 12, to give the necessary strength to the jaw against breaking across where it is otherwise weakened by the nut engaging faces being out into the same) the spring between its ends is convexly curved relative to such bulging surface so as to avoid contact with the same even when the movable aw is fully opened and partly depends into the slot immediately ahead of the spring, as shown in Fig. 2.

From the foregoing description it will be readily seen that 'I have roduced such a device as substantially ful s the objects of the invention as set forth herein.

While this s ecification sets forth in detail the present and preferred construction of the devlce, still in practice such deviations from such detail mdy be resorted to as do not form a departure from the'spirt of the invention, as defined by the appended claims.

Having t us described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. A wrench including a handle shank having a fixed'jaw on one end and a longitudinal slot adjacent the jaw, a shank projecting into the slot, a pivot pin through both shanks, a jawon the pivoted shank outwardly of the slot, said pivoted shank and jaw being arranged for substantially 90 of arcuate movement relative to the handle shank, a flat spring member projecting through the slot beyond the pivoted shank and fixed at one end to the handle shank on the same side thereof as that from which the movable jaw pro: jects, and a cam surface formed on the adjacent edge of the movable shank disposed relative to the shank pivot so as to engage the spring at substantially a constant point and ad acent the outer end of the latter throughextent of openin the pivoted shank and fixed at one end to the handle shank on the same side thereof as thatfrom which the movable jaw projects, and a cam surface formed on the adjacent edge of the movable shank for engagement with the spring and so disposed relative to the pivot pin and to the s ring as to cause the spring to be increasing y compressed between the closed and open positions of the movable-jaw while maintaining the s ring engaged with the cam at a constant pomt in thelength of the latter.

3. A structure as in claim 2, in which the spring, intermediate its ends, is shaped to avoid contact with the back edge of the movable shank beyond the cam irres ective of the g movement 0 the movable shank and aw.

In testimony whereof I afiix my leigpature.

HOMER A.

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