US2332971A - Wrench - Google Patents

Description

Oct. 26, 1943. w, JOHNSON WRENCH Filed March 15, 1941 2 Sheets-Sheet l fimgtor;

Oct. 26, 1943. w. JOHNSON WRENCH 2 Sheet-Sheet 2 Filed March 15, 1941 N TED-r Patented Oct. 26 1943 1 ,WRENCH I eon ard W. Johnson, .ljata'viafllh; Helena Johnson, executrix oisaid Leonard W; John My inventionrelates to torque wrenches and has particular reference to a torque-wrench of the slip Joint variety; in which a friction member mounted in a lever is held in engagement with a work engaging member, preferably in the form of a circular boss, andin whichth'e friction memberslips or moves awayfrom its seat in the recess provided for the reception of: the friction member in the work engaging member upon a predetermined-force being applied to a nut. I

This application is a continuation inpartof my application Serial No. 255,405, filed February 9; 1939, this presentapplication disclosing a com- :bined stopandathrust pad'in addition to the elements mentioned abovewhich I have found 2 both desirable and necessary to the proper op.- .eration of the-wrench." 1 1 1 fiAnother and further object of my' invention is the provision of a torque wrench providedfiwith a stop which prevents the: turning-lot theile'ver portionof the wrencha greatdistance afterthe breaking or slippa eof the joint has occurred;

thereby adding itoithe speed and ease of operation of thelwrenchand also-preventing the. lever portion of the wrench from turning such a distance. that 1 a. workman is liable to. injury. from slipping due to the sudden-release of stheifriction mem r... :I :1? 11'1 1 ;Another and further object of wmyqinvention is the provision oia torque wrenchhaving-a-stop member. therein. which permits pulling nuts tighter when theslotsin castellated nuts do not line up with holes in'the, bolts for cotter keys atterthenuts have been pulled ;to a.prede-. termined pressure This is particularly advantageous in the setting of bolts on the connecting rods of internal= combustion motors.

A furtherobject: of my invention is thegprovi sionof a wrench having, a thrust pad embodied therein, which acts on .thabossto produce friction and adds to the accuracyof the wrench,

in that it absorbs to agcertain degree the force exerted upon the lever portion of the Wrench when given a;shock pull-.as distinguished from a s t ady. Pu l-.

' No two workmen pull aw rench. in exactly -the same manner although to achieve the1best results with 13', sllp =joint ,torquewrench, alslow, steady pull, gradually increasingin force until the ,J'ointbreaks,,;is,most desirablei .However,

at the 3 speed; of pperation; with which 1 these 1 wrenchesare employedkin the final. setting of the,nut a- 1,workma'n, frequently will giv the wrench a. quick, :hardpull, with ,the muscles of ms arm tensed, 'proq pingiwhat is in t'l'ie na ture. o1 ashock' pumn which case the nut is pulled improved wrench, taken on l A Q5011, deceasedsassignor toHele'na E. Johnson I 1 Application March 15,1941, Serial.No.383,486 I H 70mi s; 401. 81- 53) more tightly on the bolt than what is secured with the slow, steady pull. For this reason I prefer'to add -the thrust member to produce friction in the boss; which tends to lessen the .efiectsof the shock pull and increases'theaccuracy of the wrench whether a-pull is slowjand steady, or whether a fast pull is resorted to or scribed-above as a shockpullp whether the lever is pulled with what is de- 11 A further object of'my invention is the provision of a thrust member opposite the line of force .exertedby the friction member forming the: slipwjoint, wherebythe tendency of the wrench to cant during :thepulling thereoftis prevented, thereby preventing a binding of some of themoving parts of the wrenchand resulting in increased accuracy of the wrench. 1

These and other. objects of.my invention will bemore fully and betterunders'tood by reference to the'accompanying sheets of. drawings, and. in which-e 1 11 V; .J 'Figure 1 isa.longitudinalsectional view of my Figures is .a vertical View; partially in sec-,

tion' and partially in elevation, of the wrench showninFigureB; and M H y 1 Figure 5 is'aw cross-sectional view taken .on

line 5-5 ofnFigure 3. 1

Referring now specifically to the, drawings, and

1 inwhich like reference characterswrefer to like parts throughout, a lever I0 is shown, having a head portion ll having a circular. opening therein, Within which a circular boss" or work engaging member is positioned. The boss has trunnionsl31 and M on each side thereof, with their axes. parallel with the axis of the boss I2, the trunnion being extended to form a squared endportion I5 adaptedto engage the usual socket employed with wrenches of this type for the purpose of fitting the wrench to nuts of {varying thicknesses and contours. The lever" i0 is made up of the head portion I l having 'afho1low -trunnion I6 at one side thereof, a hollow extension I! fitted inside of, the trunnion l6 and secured thereto by means or rivets l8, l8,*anda handle 19L A socketlis formed innthe. handle [9 into which one end of the extension [I1 is fitted, the handle portion being held'to the member H by asline through the asses-21 handle --and after the critical point isreached in the use or the wrenchg the lever pi'irtion slips *on the boss, and i the friction member rides up tc ward" the side of the boss a short distance, where furthenrotative movement isprevented by the setting'thenut under therequired tension. ,When such a 'pull is exerted, the force is absorbedfto a limited extent-'by tl m resistancetomovement bet'weemthe thrust member and the boss, just at the instant when-the joint' breaks', which results" in a more accuratesetting ofthe n'utth'an' ii the thrust member were not employed. This movement is" 'somewhat limitd -biit it is suflicient to indicate to the workman that the desired tension hasbeen reached, and thereafter it is very easy to turn the wrench back to operating position ready to be used upon the next or succeeding nut, or to back up the nut slightly for use with a castellated nut, or the nut may be turned more tightly to bring the pin receiving channels in the nut into register with the hole in the bolt through which the usual cotter pin is inserted. In this manner there is no danger of the handle turning around too far, or, as often happens, ,of the wrench releasing very quickly allowing the workman to strike his hand against some adjoining pieces of machinery, thereby resulting in injury to him. l

In addition, as shown in Figures 1 and 2, the friction member produces in effect a balanced fricvarying-pressures are exerted on SaidspringQa stop in the head-portion'of the lever extending" into the-stop receiving-recessin the said boss} the stop" receiving recess being wider than the stoptherein whereby limited rotative movement of the lever and work; engaging boss isobtained, and a combined-:frictionproducing and thrust member in said head portion in engagement with the'said work engaging boss. I l '3IA' slipfjoint wrench comprising in com bination;- a lever having a handle portion and a head portion, --a work engaging; boss mounted in the said head portion having latch receivingand stop 'receiving recessesftherein, a latch member, one end 'of which engages the latch receiving re-- cess, a' spring in the handle; adjusting "means whereby varying pressures are exerted on 'said spring, and a stop in the head portion of the lever extending into the stop receiving recess in the said boss, the stop receiving recess being wider than the stop therein whereby limited rotative movement of the lever and work engaging boss is obtained and of a width sufliciently narrow whereby the latch member is partially retained in the latch receiving recess at all times.

4. A torque wrench comprising in combination, a lever having a head portion at one of its ends, a cylindrically shaped work engaging member in said head portion and normally movable relative thereto, said work engaging member havingat least one pair of recesses in the periphery thereof, one of said recesses being fashioned to receive a latch member and the other recess to receive a stop member, a latch member in said tion or at least reduces it to a point somewhat small in area, and enables the wrench to be pulled in a straight direction without a tendency to cant or tip over, producing, in effect, a floating action of the wrench. In this way I have found that a material degree of safety and also an addedamount of accuracy is provided in a torque wrench, which is not possible to secure with other types of torque wrenches now in use.

3 invention.

What is claimed is:

1. A slip jointwrench comprising in combina tion, a lever havinga handle portion and a head portion, a circular work engaging boss mounted in said head portion having a latch receiving recess and a stop receiving recess wider than the stop to be received therein in its outer periphery, a latch in the handle portion forming a slip joint between the lever and the work engaging boss, astop on said head portion extending into the said stop receiving recess, a spring in said handle in engagement with one end of the said latch member, adjustable abutting means for said spring mounted in said handle, and a combined friction producing andthrust member in said head portion in engagement with the said work engaging boss.

2. A slip joint wrench comprising in combination, a lever having a handle portion and a head handle, a spring mounted in the lever in abutting engagement with the rear end of said latch member, an adjustable follower in the said lever forming an abutting support for the said spring,

3 and a stop in said head portion extending into the recess in the work engaging member, the said stop receiving recess being sufficiently wider portion, a work engaging boss mounted in the than the stop to permit limited relative movement of the work engaging boss and the lever to an extent insuflicient to allow a complete disengagement of said latch member from said latch receiving recess.

5. A torque wrench comprising in combination, a lever having a head portion at one of its ends, a work engaging member in said head por-' tion and normally movable relative thereto, said work engaging member having at least one pair of recesses in the periphery thereof, one of said recesses being fashioned to receive a latch member and the other recess to receive a stop member, the outer surface of the work engaging member being circular, a latch member in said handle, a spring mounted in the lever in abutting engagement with the rear end of said latch member, an adjustable follower in the said lever forming an abutting supportfor the said spring, a stop in said head portion extending into the recess in the work engaging member, the said end of which seat's inthelatch receiving recess} a. spring in the handleg a'djusting means-whereby

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