US2558440A - Adjustable fulcrum pliers - Google Patents

Description

June 26, 1951 J. N. JOHNSON ADJUSTABLE FULCRUM PLIERS Filed April 22, 1947 INVENTOR.

JOSEPH N. JOHNSON BY AT TORNEYS Patented June 26, 1951 ADJUSTABLE FULCRUM PLIERS Joseph N. Johnson, Oakland, Calif. Application April 22, 1947, Serial No. 743,002-

An object of my invention is to provide a plier wrench which is an improvement over the wrench shown in my Patent No. 1,866,771, issued July 12, 1932. In the patent Ishow a wrench that can be used as a pipe wrench, monkey wrench or pliers due to the fact that one of the jaws has two straight object-gripping edges reentrantly inclined to each other and the other jaw has a convex cam-shaped edge. The cam edge cooperates with the re-entrantly inclined edges so that the wrench will have a tendency to bind more tightly upon a nut or other object as more pressure is applied to the object for rotating it. It is not necessary to grip the two handles of the wrench more firmly as greater force is used for rotating the object, as is the case with the usual pliers. The cam will automatically cause the handles to tend to swing together as more force is applied to rotate the object.

In the present invention, the jaw provided with the straight edges re-entrantly inclined, has an outer straight gripping edge that makes an obtuse angle with the adjacent straight edge. The other jaw has an abutment positioned at the outer end of the cam-edge and the abutment has an edge making an obtuse angle with the cam edge and an outer straight gripping edge that cooperates with the outer straight gripping edge of the first jaw for gripping an object therebetween. The re-entrant edges on the one jaw and the abutment on the other providing sufficient space between the jaws and in back of the outer straight gripping edges to provide space for receiving a projection of the object gripped, such as the head of a cotter pin.

A further object of my invention is toprovide a plier wrench that has novel means for quick adjustment for spreading the jaws to grip objects of various sizes. The quick adjusting means is designed to maintain the jaws in the same relative positions regardless of the adjustment, the only change being the greater or less spacing of the jaws one from the other.

A Wire cutting means is incorporated in the plier wrench and the re-entrant edges cooperate with the cam edge for guiding the wire into the wire-receiving recesses. The plier wrench is sturdy and simple in construction.

Other objects and advantages will appear in the following specification, and the novel features of the device will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings forming a part of this application, in which:

3 Claims. (Cl. 81-513) Figure 1 is a side elevation of the plier wrench showing the jaws gripping a hexagon nut;

Figure 2 is a transverse section taken along the line IIII of Figure 1;

Figure 3 is a side elevation of the jaws of the plier wrench showing them in a spread position for gripping a larger square nut;

Figure 4 illustrates the jaws gripping a cy lindrical object; Figure 5 illustrates the jaws gripping a cotter pin with sufficient space being provided forjreceiving the, cotter pin head; Figure 6 is an enlarged view of thejaws show-. ing the wire cutting means; and

Figure 7 is a greatly enlarged view illustrating the severing of a wire by the wire cutting means;

While I have shown only the preferred form of my invention, it should be understood that various changes or modifications may be made within the scope of the appended claims without departing from the spirit and scope of the invention.

In carrying out my invention, I provide a plier wrench that has two handles A and B. The handle A has a straight shank portion Al with a straight edge I and a slot 2 paralleling this edge. The slot has spaced notches 2a extending along the side disposed nearest the straight edge I Figure 2 shows the handle B carrying the shank 3 of a pivot bolt C that pivotally connects the handles A and B together. The bolt shank 3 is rigidly secured to the handle 13 and is rotatably and slidably received in the slot 2. Fig ure 6 shows the bolt shank 3 provided with opposed flattened sides 311 that are disposed a suificient distance apart to permit the shank to he slid along the slot 2 when the handle B is opened with respect to the handle A for bringing one of the fiat sides 311 into sliding contact with the straight edge 2b of the slot.

A four place slip joint is provided for the pivoting of the handles A and B by the bolt C and notched slot 2. In Figure 6 the bolt shank 3 has been rotated in the slot 2 for causing one of its two opposed arcuate sides 3b to contact the straight side 2b of the slot and the other arcuate side 31) to enter the adjacent notch or recess 2a.

The bolt shank in this position cannot he slid.

along the slot 2 and the two handles A and B are pivotally connected together at the desired place along the slot. There are four notches 2a and therefore four positions into which the bolt C can be moved. The bolt has a head 4 at one end. A disc 5 is mounted on the bolt at the other end and is held in place by upsetting the projecting end of the bolt as shown at 6. The twohandles are permanently locked together by this arrangement.

The handle A carries an integral jaw D while the handle B carries an integral jaw E. The jaw D extends at an angle to the straight edge I of the handle shank Al. Two straight object gripping edges I and 8 are formed on the jaw D and are re-entrantly inclined with respect to each other. The edge I has teeth. la whilev the edge 8 is: preferably smooth. In addition to these two re-entrantly inclined edges, I provide an outer edge 9 that makes an obtuse angle with;

the toothed edge 1. The outer edge. 9. is also. provided with object-gripping teeth 9a, but'these are preferably smaller in size thantheteethlw...

The jaw E extends beyond the straight, edge I of the handle shank Al about the same distance as the jaw D. A convex cam edge," [0. is provided on the jaw Di and it cooperates with the re-entrantlyinclined' edges. ina mannerher-einaft'er described. The cam. edge [0. extends at an obtuse angle to. the handle B and it. has teeth Illa of substantially the same size as the. teeth la. An abutment. El is positioned. at the outer end of the cam edge lllliand this. abutment has an inner smooth edge ILII making an obtuse angle with the cam edge III andan outer toothed edge 12 making an obtuse angle with thesmootlr edge. H. The. teeth lZd enthe outer abutment edge. [2 are preferably of the same size asthe teeth 9a and the two objectegri'pping, edges 9 and, I2 are of. about the same length. Before describing the operation. of, the. plier .wrenchit is best. to set. forth. the structure of the wire cutter..

The wire cutter. i shown. in Figure 6 andin enlarged detail inFigure 7 The straight edge II has a U-shaped. wire-receiving. recess t3 therein with opposededges- One ofthe opposed edges. l-3a.. merges into. the. edge 8 and constie tutes one of the wire-severin edges. A. coopcrating wire-receiving U.-shaped-. recess l3 at the base of the. jaw Elhas. opposed edge with the edge Ma constituting a. wireecutting edge and merging into. the cam. edge l0. Figure 6 shows a. wire F received in the recesses. l3. and M. The handles AandB have been. moved toward each other for moving,- the. cutting edges 1.30.- and I la into engagement with the wire.

It willbe noted fromFigure-"I that as the cutting edges l.3a and. Ma. are: moved toward each other, the outer ends of these edges will pass eachother. before the inner ends. This results in. the wire being. forced to the bottoms of the:

recesses [3 and. HIv duringthe. severing thereof". There will be no. tendency for the. wire to be forced. out. of the. recesses, but rather the wedging. action of the. edges Mia and Ma, as they are swung about their commonpivot bolt C will be to trap the wirev and. force it toward the bottoms of the recesses. A.better cutting. of: the wire. results.

Furthermore it. will be seen thatv the wire can' be fedinto the registering. recesses I3 and I4 very easily. The re-entrant edge 8 of thejaw'D- and the camedge H] of the jaw E guide the wire into the. aligned recesses because the edge 8 merges into. the recess edge I3a and the camedge HI merges into the recess edge I 4a.

The abutment EI- permits the plier to ratchet on a nut without pulling loose. The abutment acting as a ratcheting retainer tends to hold the pl-ier on the nut during the ratching movement and the'edge 9:01.- the jaw- D actsas an escapement edgecooperating with the edge 1:2 of-i'th'e abutment to permit easy entry and exit for the work entering or leaving the jaw. The inclined edge ll of the abutment forms one of the working faces that engages with a face of a hexagon nut, see Figure 1. I do not wish to be confined to any definite number of notches 2a in the slot 2. I have shown four notches although these may be increased to five or reduced to less than four if desired.

In. operating the device, the straight edge 1 of the jaw D is considered the stationary edge and the convex cam edge [0 of the swingable jaw E is considered the movable cam-shaped edge. The second and third pivot positions shown in; Figures 1 and 3 are the ones most commonly used, A i hex'nut is gripped by the pliers in Figurel and a square nut is gripped in. FigureB. In Figures 1, 3, 4, 5 and 6, I show a dot dash line lb coinciding with the straight edge 1 and extending to the. right of the. edge. I also show another dot dash line 20. extending, through the centerv of the bolt 4 and paralleling the edge 21 of the slot 2. These two lines intersect and make an acute angle which is in.- dicated at a. It will also be seen that the convex cam edge l9 extends almost at right angles to the line 20 when gripping an object.

It willv be seen from Figures 1,v 3v and v4, that the convex cam edge In is. substantially parallel to the straight edge 1 when the. two. jaw edges are in object gripping position. The. con-- vex edge ID will remain substantially the same distance away from the line 20 for all four ad'- justments of .thepivot, bolt C and therefore, the. jaws can grip larger objects as readily as smaller ones. Inasmuch as the convex cam edge H1 makes an obtuse angles with the, length of the handle B. the edge ID will create a camming. action on the object gripped as the handle. 13- is swung toward thehandle A and willtend to. wedge the object against, the straight edge 1, to create a vice like grip on. the object.

Iclaim:

1. A plier wrench having two handles with pivot means. therebetween adjustable along a. predetermined line; an upper jaw integral with: one handle; a lower jaw integral with the. other handle; the jaws projecting laterally from their respective handles, with one jaw overlying the. other; the upper jaw havin inner and outer. straight edges reentrantly inclined. relative toone another and so arranged that. a line coinciding with the outer reentrant edge will forman acute angle with the line along which. the pivot means is adjustable; the lowerjaw having a convex cam-shaped edge so arranged that. a line passing through. the. ends. thereof will make an obtuse angle with its handle, and an abutment disposed at the outer end of this edge and projecting toward theupper jaw; the outer reentrant. grippin edge of the upper jaw being disposed substantially parallel to and mating with the convex cam-shaped edge of the lower jaw regardless of the position that the pivot means occupies along the pivotmeans adjusting line, and while the handles are maintained in a relation with respect to each other for causin the jaws to grip anobject.

2. A wrench having two jaws adjustablypivoted together and each having an integral handle; the upper jaw having inner, middle and outer straight edges; the inner and middle edges bein reentrantl'y inclined with respect to each other and the outer edge making an obtuse angle with the middle edge and constituting an 5 escapement edge for an object being gripped; the lower jaw having a convex cam edge so arranged that a line passing through the ends thereof will make an obtuse angle with its handle, the lower jaw havin a ratcheting retainer disposed at the outer end of the cam edge; the ratching retainer having an edge which approximately parallels the escapement edge on the upper jaw when the two laws are in ratcheting position and which thereby pro- 10 vides easy entry and exit for work entering or leaving the jaws when the jaws are opened a slight distance beyond ratchetin position.

3. A wrench having two jaws adjustably pivoted together along a predetermined line and each having an integral handle; the upper jaw having inner, middle and outer straight edges; the inner and middle edges being reentrantly inclined and the outer edge extendin approximately at right angles to the predetermined line of adjustment; the lower jaw having a main curved edge so arranged that a line passing through the ends thereof will make an obtuse angle with its handle, the lower jaw havin an outer edge substantially paralleling the outer 6 edge of the upper jaw when the middle straight edge of the upper jaw approximately parallels a line passing through the ends of the curved edge of the lower jaw.

JOSEPH N. JOHNSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,050,683 Overlander Jan. 14, 1913 1,283,217 Kurtzhals Oct. 29, 1918 1,577,155 Anderson Mar. 16, 1926 1,678,313 Atkinson July 24, 1928 1,800,447 Froeschl Apr. 14, 1931 1,950,362 Manning Mar. 6, 1934 FOREIGN PATENTS Number Country Date 839,175 France Dec. 26, 1938 99,868 Sweden Sept. 17, 1940 573,204 Great Britain Nov. 12, 1945

Images