US 2519973 A
Description (OCR text may contain errors)
Aug. 22, 1950 L. c. MEAD WRENCH TYPE PLIERS Filed March 20, 1948 INVENTOR L. C. Mead ATTORNEYS Patented Aug. 22, 1950 UNITED STATES PATENT OFFICE 2 Claims.
This invention is directed to, and it is an object to provide, improvements in that kind of a mechanical hand tool known generally as looking or wrench type pliers.
One object of the invention is to provide wrench type pliers which include a novel, handle locking unit, especially with respect to the adjusting assembly thereof.
Another object of the invention is to provide a handle locking unit, as in the preceding paragraph, in which said adjusting assembly includes a threaded shank extending into one of the channel-shaped handles of the tool, and a rotary adjustment nut on the shank working through registering openings in opposite sides of said handle for ready finger access; there being a novel cating and retaining arrangement, for the nut, working in matching relation in said openings.
A further object of the invention is to provide the tool with a novel handle releasing unit cooperating with the locking unit to open the pliers from locked position; said handle releasing unit being a modification of the design Shown in copending application, Serial No. 645,761, filed February 6, 1946.
A further object of the invention is to provide improvements, in looking or wrench type pliers, which enhance the convenience and practicability of the tool, and to provide such improvements which will be exceedingly effective for the purposes for which the same are produced.
These objects are accomplished 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:
Fig. 1 is an elevation, partly in section, of looking or wrench type pliers embodying the present invention; the handle locking unit and handle releasing unit being shown in full lines in the positions occupied by the parts thereof when the tool is in use, and shown in dotted lines in the positions occupied by the parts thereof when the tool is released from the work.
Fig. 2 is a fragmentary sectional elevation illustrating the handle locking unit, particularly the adjusting assembly thereof.
Fig. 3 is a cross section on line 33 of Fig. 2.
Fig. 4 is a longitudinal section on line 4--4 of Fig. 2.
Referring now more particularly to the characters of reference on the drawings, the invention is here embodied in locking or wrench type pliers of the type which include a fixed jaw I and a movable jaw 2; the latter being of generally bellcrank configuration and secured at its inner end by a transverse pivot 3 for adjustment relative to said fixed jaw l.
Adjacent faces of the jaws l and 2 include teeth 4 adapted to frictionally engage the work 5 gripped in the tool. The fixed jaw l is formed, at the forward end, and as an integral part of, a rigid handle 5; the other relatively movable and cooperating handle I of the tool being of reduced length and attached, at its forward end, by a transverse pivot B to the movable jaw 2 intermediate its ends, i. e. generally at the elbow of the bellcrank.
The rigid handle 6, and the relatively movable handle 1 are of channel configuration, as shown, with the channels open toward each other.
A pivotally mounted, releasable, handle locking unit, indicated generally at 9, is connected to the relatively movable handle I at its forward end but short of the movable jaw 2 and thence extends in a rearward and diagonal direction to connection with the rigid handle 6; all as hereinafter described in detail. The releasable, handle locking unit 9 is adjustable as to length, and its arrangement and disposition is such that when the work 5 is frictionally engaged between the jaws I and 2 by relative approaching motion of the handles 6 and I, said locking unit 9 snaps inwardly beyond dead-center, then eifectively but releasably holding said handles against separation. The dead-center line of the locking unit 9 is indicated at It, and said unit comprises the following structural arrangement:
The numeral ll indicates an adjustment bolt formed, at its forward end, with a head l2 attached by a cross pin l3 in the channel-shaped, relatively movable handle 1 near but short of the rear edge of the movable jaw 2.
The opposite end portion of the bolt H is formed as a threaded shank M, which shank extends into the channel of the rigid handle 6 in intersecting relation to a pair of circular, registering side openings l5. An adjusting assembly, indicated generally at 16, is carried on the threaded shank I4 and works in said openings I 5; such assembly comprising the following:
A circular adjustment nut I1 is threaded on the shank I4 and is of such diameter that it projects, for finger access, through and beyond the circular openings l5; such adjustment nut being peripherally knurled to prevent finger slippage.
Substantially semi-circular locator segments l8 are disposed on opposite sides of the circular adjustment nut l1 and are radially bored, as at [9, for the passage of the threaded shank l4 therethrough. The locator segments provide a locating and retaining arrangement for the ad justment nut I1, and such segments ride in matching peripheral engagement in the openings of the rigid handle 6.
The adjustment nut l1 includes reduced diameter hubs 29 at opposite ends which bear in corresponding sockets formed in the locator segments l8.
To adjustthe effective length of the locking unit 8, itisonly necessary that the exposed part of the adjustment nut ll be finger manipulated to cause either advance or retraction of the adjustment bolt H; dependent of course upon the thickness of the work 5 to be engaged between the jaws and 2.
The arrangement is such that the adjustment nut ll can be engaged and manipulated by the fingers of the same hand which is holding the tool for engagement with the work. This greatly adds to the convenience and practicability of the tool.
When it is desired to release the tool, the relatively movable handle i must be swung laterally outward, with attendant breaking of the locking unit across the dead-center line !9 in the same direction. To this end there is employed a handle releasing unit which comprises a modification of the uni-t for this purpose shown inthe aforesaid copending application, Serial No. 545,761..
In the present embodiment the handle releasing unit comprises an elongated release lever 21 normally disposed within the channel of the relatively movable handle '5 and projecting out of the rear thereof as a finger piece 22. The elongated release lever 2! terminates, at its forward end, adjacent the head l2 of the bolt II, and slightly to the rear of the cross pin 23 the lever 2'! is pivoted by a cross pin 23. in the channel of said handle '5. The cross pin 23 is adjacent but short of the forward end of the lever 2|, said forward end being in the form of a laterally outwardly extended or rounded nub 2 The nub 2A bears in a corresponding seat 25 of an arched leaf spring 26 resting in the channel handle 1; the described nub and seat arrangement being all that is needed to hold said spring in place. Slightly to the rear of the cross pin 23 the lever 2! is formed with a laterally inwardly extending cam 27 which bears against the ad acent side of the head I 2.
When the tool is in its locked position, as in full lines in l, swinging of the lever 2! inwardly by the finger piece 22 causes the cam 21 to forcefully work against the head l2 accomplishing relative separation of the handle and looking unit 3. With this relative separation, the handle 1 moves outwardly and said locking unit travels across the dead-center line It to release position of the pliers. After a pliers releasing operation, the spring 25 returns the lever 21 to its normal inoperative position within said handle 1.
From the foregoing description it will be read- 11y seen that there has been produced such a device as substantially fulfills the objects of the invention, as set forth herein.
While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.
Having thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:
1. In wrench type pliers including relatizely movable handles and 2. beyond dead-c nter lockunit connected diagonally between said handles; a releasing unit comprising a lever extending lengthwise of one handle along its inner side, the forward portion of the lever being adjacent the looking unit, a cross pin pivotally securing the lever to said one handle adjacent but short of the forward end of said handle, a leaf spring between said one handle and forward end of the lever urging the same toward said one handle rearwardly of the cross pin, and a inwardly projecting can; on the lever nt but rearwardly of the cross pin, said aring against the locking unit whereby 'elative separation of the same and said upon swinging of the lever laterally 1' lg; said spring being arched toward the ad of the lever, and a laterally outxw" to u r e: ndin on said end bearing against the 2. in wrench type pliers including relatively movable handles, the movable handle being channel-shaped and opening inwardly, and a beyond dead center locking unit connected diagonally between the handles; a releasing unit comprising a lever extending lengthwise in the channel of the movable handle, the inner end of the lever being adjacent the locking unit, a cross pin pivoting such inner end of the lever to the movable handle adjacent but short of the inner end of such handle, a projection on the lever extending inwardly beyond the pin and terminating in a nub, an arched leaf spring separate from the movable handle but slidably mounted in the channel thereof adjacent said lever projection, the arch of the spring having a depressed seat,
'the nub of the lever projection resting in said seat, and cam means on the lever on the side of the pin opposite the projection, such cam means being engageable with the locking unit and effective to release the same upon inward swinging of the lever.
LAWRENCE C. MEAD.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 561,274 Palmer June 2-, 1896 1,717,725 McGill June 18, 1929 2,388,580 Snell (1) Nov. 6, 1945 2,436,497 Snell (2) Feb. 24, 19 .8 2,463,721 Spencer et al. Mar. 8, 1949 2,478,728 Ward et al. Aug. 9; 1949 2,481,435 Meunier Sept. 6, 1949 2,489,895 Kash Nov. 29, 1949