US3074164A

US3074164A - Multiple lever tool

Info

Publication number: US3074164A
Application number: US164062A
Authority: US
Inventors: Thomas M Porter
Original assignee: HK Porter Inc
Current assignee: HK Porter Inc
Priority date: 1962-01-03
Filing date: 1962-01-03
Publication date: 1963-01-22
Anticipated expiration: 1980-01-22

Description

7 Jan. 22, 1963 Filed Jan. 3, 1962 T. M. PORTER MULTIPLE LEVER TOOL 2 Sheets-Sheet 1 "W ll Inve222ba Taiomms M.Po3 ei Jan. 22, 1963 Filed Jan. 3, 1962 T. M. PORTER MULTIPLE LEVER TOOL 2 Sheets-Sheet 2 ited ' state This invention relates to tools of the multiple or compound lever type in which jaws which operate on the work are pressed against it through the operation of a toggle moving towards the straightened position, and the object is to provide an improved construction which permits the relative positions of the pivotal centers to be adjusted as necessary to control the action.

Multiple lever tools of the type disclosed in the patents to Lindsay 146,829 and 147,850 in which the jaws are actuated by a toggle are well known and the tool herein illustrated and described is of that general type. Heretofore various constructions have been provided for adjusting the relative positions of the pivotal centers of the toggle, and recently the patent to Klein, 2,910,900, has disclosed a construction wherein a massive portion of one lever is cleft to provide integral pivot-supporting parts for receiving the centers of a toggle link which parts are substantially inflexible under minor bending pressure, yet may be deformed without danger of fracture in order to adjust the spacing of the pivots, the deformation being effected by means of a jackscrew carried by one part and bearing on the other and serving to take the thrust of heavier working loads. The present invention provides means for relatively positioning the projecting pivot-supporting parts in use and providing for adjustment of their relative positions, which means leaves the parts intact, avoids the presence of a laterally projecting screw which may be fouled in use, and generally provides a neater and more compact structure, simple to manufacture and of superior strength.

The invention will be well understood by reference to the following description of the embodiment thereof shown by way of example in the accompanying drawings, where- PEG. 1 is a front view of an adjustable, hand-driven, toggle-operated tool of the kind commonly called a bolt clipper constructed in accordance with the invention, the parts being in closed position;

FIG. 2 is a front view of the forward end portion of the left-hand operating lever of the tool on a larger scale;

FIG. 3 is a central vertical section through the expanding and supporting block of FIG. 2 on an enlarged scale, with parts broken away;

FIG. 4 is a section on lines 44 of FIG. 3;

FIGS. 5 and 6 are views similar to FIG. 2 but showing different structural embodiments; and

FIG. 7 is a section on line 7-7 of FIG. 1.

In the following description the words right and left have been used with reference to the drawings and the words forward and rearward are used from the point of view of a user grasping the tool at the lower end viewing FIG. 1 and holding it extended away from his body, forward being toward the jaw-carrying end at the upper portion of FIG. 1 and rearward in the direction of the handle extremities at the bottom of FIG. 1. The words are of course relative for convenience of description and have no inherent significance.

Referring now to the drawings, the tool shown comprises a pair of head levers l3 and 14 which are pivoted together and herein, since the levers do not cross, they are pivoted at intermediate points of their length on plates 15. The forward portions are jaws 20* and 21,

I, 3,674,354 Patented Jan. 22, 1963 which as shown have opposed edges of the nipper type which moving toward one another first indent the work and, as their motion together proceeds, sever it and the rearwardly extending

portions

22 and 23 are tails which when forced apart cause the jaws to move together and operate on the Work. The actuating levers l1 and 12 which move the jaw tails are, mechanically speaking, bent levers herein illustrated as having a compound construction not necessary to describe and not essential to the invention, and these levers have at their forward extremities knuckle portions 33 and 34 (see FIG. 7) receiving a central pivot it? joining them together and, respectively at points closely adjacent to this pivotal point 40, knuckles 32 and 35 (see FIG. 7) which are joined to

knuckles

22 and 23 on the tails of the head levers by pivot pins to provide relatively short arms organized as a toggle of which the centers are 40, 41 and 42, although in the example illustrated the short arm between the

centers

40 and 42 does not physically extend in a straight line between them. The actuating levers are extended beyond the

centers

41 and 42 rearwardly, and herein form long actuating

handles

11 and 12.

The tool shown is adapted to be operated by the hands of the operator grasping the rearward ends of the levers, moving the same together without the intervention of mechanical or power-increasing mechanisms or motordriven mechanism, the application of which to such actuating arms is however sufiicientl'y obvious. t is not necessary that both levers move.

Referring to FIG. 1 it will be seen that if the

levers

11 and 12 were moved outwardly to the right and left respectively, the center 46 of the toggle would move downwardly drawing together the

centers

41 and 42 and opening the jaws 20' and 21 of the tool. In the opposite action the toggle is straightened, presses the

centers

41 and 42 apart with great force and exerts correspondingly great pressure on the work. In accordance with the invention the relative position of the three

centers

40, 41 and 42 of the toggle is subject to adjustment and herein 1 have shown such adjustment at the left-hand side viewing FIG. 1. For this purpose the forward end portion of the bent lever at the left including the forward end of handle 12 and the

knuckles

34 and 35, consists of a massive body of suitable metal, preferably forged steel, which is ductile in the sense that it may be deformed by the means to be described without danger of fracture, but having such yield strength that in the cross sections involved the parts will be substantially inflexible under 50 minor bending pressures substantially lower than those exerted by means of the toggle mechanism. Theknuckles 34 and 35 which receive the

pivots

40 and 42 are formed in this block of metal which as best seen in FIG. 2 is cleft rearwardly in a plane extending between those knuckles to provide integrally based pivot-supporting parts 44 and 4,5 for supporting the pivots at

centers

40 and 42 respectively, the

knuckles

34 and 35 being at the outer ends thereof. These parts are substantially inflexible for instance in the movement clockwise about the center 4.0 where the load is merely that involved in opening the aws.

Apart from a few details the preceding three paragraphs would be equally applicable to the structure disclosed in the Klein Patent 2,910,900 already referred to and intentionally substantially duplicate a portion of the specification of that patent.

Referring now to the left-hand side of FIG. 2, the forward portions of the internally facing side of the

pivotsupporting parts

44 and 45 at opposite sides of the cleft are provided with rearwardly and inwardly inclined surfaces 46, with which cooperate the sides of a rearwardly tapered block 48 of generally rectangular cross section,

and it will be apparent that if the block 48 is forced rearwardly, downwardly in the figure, between the two

parts

44 and 45, it will wedge them apart, separating the

knuckles

34 and 35 and centers 49 and d2. 'Herein the block is traversed (see FIG. 4) by a bolt 59 on which it swivels, being retained by the head 54, the thread of the bolt entering a thread in the body at the base of the cleft. A recess 52 in the head of the bolt has flat sides to receive a wrench of the type commonly used for setting up hollow-headed setscrews. Screwing in the bolt draws the block downwardly between the converging surfaces 45 and the block when at rest supports the two parts 43 and 45 from inward movement toward one another.

The word wedge is put in quotation marks in the preceding paragraph. The surfaces 46 may correspond to the sides of a triangular prism, but it will be apparent that if the

pivot supporting parts

44 and 55 are forced outwardly they tend to swing about their inner ends and the angle between the surfaces 46 will change. If the block 43 were similarly a .trangular prism it would engage only at its inner edge as the two pivot supporting elements move apart and would act at a point relatively far removed from the centers 4%) and 42. Therefore, preferably the block is shaped as in F168. 3 and 4, the sides being curved. The side elevation might be characterized as a truncated ogive. if the block 43 moves rearwardly the surfaces 46 move along these curved surfaces of the block, the line of contact moving rearwardly but being maintained throughout the transverse width of the block. These sides of the block may be relieved centrally as best seen at 55 in FIG. 4, to provide a projecting rib at each side so that the bearing of the block on each of surfaces -36 is along two narrow zones at either side of the central plane. In effect there are then two members acting symmetrically to the central plane for supporting and for flexing the pivot-supporting parts, which members are supported from a central core to which the force to move them is applied by means of the screw.

In FIG. the block 48, instead of being swiveled on the unthreaded end of a screw bolt, is threaded onto one end of a screw Eda, the other end of which screws into a threaded opening at the base of the cleft as in the construction of PEG. 2. An angular portion 52a is provided for the application of a turning tool. Since the distance which the block 48 moves is short, but the force which it must exert to. flex parts 4 and 45 is great, this compound screw preferably has threads of the same hand, but with dilferent numbers of turns per inch, so that turning of compound screw Sba in a direction to unscrew one end, tends to screw in the other. That is, Etta is then a diiferential screw. The movement of the block is slow, and a high mechanical advantage is provided to permit application of the deforming force to the

parts

44 and 45.

In the modification shown in FIG. 6 the surfaces 4615 at the inner face of pivot-supporting

parts

44 and 45 incline rearwardly and outwardly instead of rearwardly and inwardly as in the case of the similarly located surfaces in FIGS. 2 and 5, andthe block 48b is inverted relatively to block 4-8 in those figures, and it acts to force apart centers 4b and 42 when it is moved forwardly. For this purpose it may be mounted on a screw 59b the lower end of which is rotatably stepped in a socket at the base of the cleft, and the screw 59b is provided with an enlarged portion 52b to which a turning tool may be applied. The block is held from turning with the screw by means of small plates 56 attached thereto and overlying the sides of the parts 44 and The construction is of particular utility in small tools wherein the distance between the centers 4% and 42 is relatively short. Where space is ample the other modifications may be preferred as the body element would be easier to machine.

I am aware that the invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as iilustrative and not restrictive, as is in fact clear in several matters from the description itself. Reference is to be had to the appended claims to indicate those principles of the invention exemplified by the particular embodiment described and which I desire to secure by Letters Patent.

1 claim:

1. In a tool of the multiple lever type comprising:

(a) a pair of interpivoted head levers having workdeforming jaws at one side of the pivot and tails on the opposite, and means for moving the tails comprising two actuating levers pivoted together at their forward ends and, adjacent to their common pivot, being pivoted respectively to said tails to provide short arms extending between the tails as a toggle, the actuating levers extending rearwardly from the tails to provide actuating arms to which force may be applied to operate the toggle,

(b) and in which tool the forward end portion of at least one of the actuating levers is a massive integral body of ductile metai in which body the pivots are organized, the body being cleft rearwardly in a plane extending between said pivots to provide integrally based projecting pivot-supporting parts essentially inflexible as against small strains,

(c) the combination with said cleft body of a block interposed between the pivot-supporting parts, sides of the block and said parts being shaped to provide outward lateral pressure on the latter to flex the said parts as the block is moved in one direction lengthwise between them and a device comprising a rotatable screw on the space between said parts and extending between said block and the bottom of the cleft for adjnstably positioning the block.

2. The combination of claim 1 wherein the sides of the block which confront the pivot-supporting parts are curved to permit the lines of contact to move along said sides as the said parts are flexed.

3. The combination of claim 1 wherein the screw is swivelled in one of the parts between which it extends and is threaded into the other.

4. The combination of claim 1 wherein the screw is compound and has threads engaging the body and block respectively.

5. The combination of claim 1 wherein inward movement of the block forces apart the pivot-supporting parts.

6. The combination of claim 1 wherein outward movement of the block forces apart the pivot-supporting parts.

References Cited in the file of this patent UNITED STATES PATENTS 2,910,900 Klein Nov. 3, 199

Claims

1. IN A TOOL OF THE MULTIPLE LEVER TYPE COMPRISING: (A) A PAIR OF INTERPIVOTED HEAD LEVERS HAVING WORKDEFORMING JAWS AT ONE SIDE OF THE PIVOT AND TAILS ON THE OPPOSITE, AND MEANS FOR MOVING THE TAILS COMPRISING TWO ACTUATING LEVERS PIVOTED TOGETHER AT THEIR FORWARD ENDS AND, ADJACENT TO THEIR COMMON PIVOT, BEING PIVOTED RESPECTIVELY TO SAID TAILS TO PROVIDE SHORT ARMS EXTENDING BETWEEN THE TAILS AS A TOGGLE, THE ACTUATING LEVERS EXTENDING REARWARDLY FROM THE TAILS TO PROVIDE ACTUATING ARMS TO WHICH FORCE MAY BE APPLIED TO OPERATE THE TOGGLE, (B) AND IN WHICH TOOL THE FORWARD END PORTION OF AT LEAST ONE OF THE ACTUATING LEVERS IS A MASSIVE INTEGRAL BODY OF DUCTILE METAL IN WHICH BODY THE PIVOTS ARE ORGANIZED, THE BODY BEING CLEFT REARWARDLY IN A PLANE EXTENDING BETWEEN SAID PIVOTS TO PROVIDE INTEGRALLY BASED PROJECTING PIVOT-SUPPORTING PARTS ESSENTIALLY INFLEXIBLE AS AGAINST SMALL STRAINS, (C) THE COMBINATION WITH SAID CLEFT BODY OF A BLOCK INTERPOSED BETWEEN THE PIVOT-SUPPORTING PARTS, SIDES OF THE BLOCK AND SAID PARTS BEING SHAPED TO PROVIDE OUTWARD LATERAL PRESSURE ON THE LATTER TO FLEX THE SAID PARTS AS THE BLOCK IS MOVED IN ONE DIRECTION LENGTHWISE BETWEEN THEM AND A DEVICE COMPRISING A ROTATABLE SCREW ON THE SPACE BETWEEN SAID PARTS AND EXTENDING BETWEEN SAID BLOCK AND THE BOTTOM OF THE CLEFT FOR ADJUSTABLY POSITIONING THE BLOCK.