US 2463721 A
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Description (OCR text may contain errors)
Patented Mar. 8, 1949 TOGGLE OPERATED PLIERS John '1. Spencer, Jr., Birmingham, and Ettore Girardello, Betroit, Mich., assignors to Detroit Stamping Company, Detroit, Mich, a corporation of Michigan Application May 31, 1945, Serial No. 595,848
1 8 Claims.
This invention relates to hand tools; and, more particularly, to toggle actuated pliers in which the. toggle linkage is adjustable to vary the looking displacement of the jaws of the pliers.
The use of a toggle linkage in pliers is, of course, old in the art; as is the use of adjusting means to.vary the effect of the toggle linkage to. obtain different degrees of displacement between the jaws of the pliers when in locking position. Normally, such pliers include a handle having one of the plier jaws at one end and a slidable mounting for a toggle link at the other end. The co-operating plier jaw is pivoted to the handle and an activating lever is pivoted to the co-opcrating jaw laterally of the point of pivotal attachment with the handle. The other end of the toggle link is pivoted to the activating lever rearwardly of the point of attachment of the lever to the co-operating jaw and relatively forwardly of. the slidable mounting referred to above. The mounting itself usually takes the form of an inwardly opening slot in the handle with a relatively restricted opening extending longitudinally of the handle and the link has an enlarged end slidable within the slot and restrained therein by the restricted opening. The rearward end of the handle is tapped and a bolt is threadedly mounted in it with the shank extending into the opening and adapted to bear against the enlarged end of the link. The head of the bolt lies rearwardly of the handle and by rotating it, the bolt may be advanced or retracted causing a corresponding movement in the longitudinal position of the enlarged end of the link and varying the locking position of the toggle linkage accordingly.
A tension spring interposed between the co-opcrating jaw and the handle urges the jaws into the displaced position and thus displaces the slidable endof the link rearwardly and into engagement. with the inner end of the adjusting bolt.
The disadvantages of this construction (and it should be. noted that despite these the tool has come into widespread use) include a necessarily increased over-all length making the pliers particularly cumbersome when operating in restricted spaces; and the impossibility of readjusting the grip or relative displacement of the plier jaws while the tool is held in the normal operating position. The first disadvantage is at once apparent on viewing the tool since the adjusting bolt must extend rearwardly of the handle a considerable distance. As to the second, the tool is normally grasped. in the right hand which extends. around, both. the handle and the lever.
When the plier grip. is to be changed, the; tool.
2 must usually be shifted to the left hand so the right hand may be used to turn the adjusting bolt head; or the right hand must be bent sharply.
at the wrist so the bolt head may be reachedwith the left hand. In either case, the tool must be withdrawn from proximity with the work which is to be engaged and the grip altered. by a process of trial and error through subsequent comparison with the work until the proper displacement is obtained.
The present construction avoids both these difiiculties and possesses additional constructional advantages as well. In essence, this invention.
contemplates the mounting of the adjusting bolt within the body of the handle with a nut thereon. extending through opposite sides of the, handle forwardly of the normal position of the hand in grasping the tool and the shank of the bolt engaging the slidable end of the toggle link in tension rather than compression. The handle, then, need be no longer than is required for a comfortable hand-grip and the over-all length of the tool is invariable. Further, when the grip is to be adjusted, the tool can still be held in the normal position with the handle downwardly andencompassed by the three lesser fingers of the hand while the lever lies within the palm. The
thumb and index finger may then engage the. head of the adjusting nut on opposite sidesof.
the handle and may rotate it in either direction to change the effective locking position of the toggle linkage. This permits the tool to be held in the normal working position during adjustment, so that the jaws may be brought into proximity with the work to be gripped and direct comparison made between the jaw displacement and th work thickness as the adjustment proceeds.
This ease of adjustment makes the tool. preeminently suited for one-hand operation; and, coupled with the decreased length, renders it usable without sacrifice of efliciency where the work space is restricted. In addition, the tool is much heater in appearance. As the adjusting bolt is enclosed within the body of the handle,
the threads are protected and the life of the de vice extended. Since the over-all length of the tool does not change with the grip adjustment, it is quiteeasy to determine whether the tool will fit within the available space-or not. A permanent connection at the slidable end of the toggle link. is practicable and the jaw spring need notbe relied upon to keep the components in operative position. It is possible touse a compression J, springeither coil or leaf-and secure. it within the. body of the tool. Other advantagesboth in construction and use will be apparent from inspection of the device.
With these and other considerations in view, the invention consists of the construction described in the specification, claimed in the claims and illustrated in the accompanying drawings, in which:
Figure 1 is a plan view of the pliers of this invention shown in the closed position adjusted for a minimum grip.
Figure 2 is a longitudinal sectional view corresponding to Figure 1 but in which the pliers are opened.
Figure 3 is a transverse section through the handle of the tool taken on the line 33 of Figure 2.
Figure 4 is a similar section taken on the line 4-4 of Figure 2.
Figure 5 is a partial longitudinal sectional View showing a modified form of the anchoring mechanism.
In Figures 1 and 2, the principal components of the device are shown assembled and include the handle III, the co-operating jaw II, the activating lever I2, the link I3 and the adjusting nut I4. The handle I is formed from a single stamping bent upon itself in such a manner as to define the forward housing I having a closed back I6 and spaced sides I1; and a substantially cylindrical rear section I8 having a downwardly opening slot I9 of restricted dimension as compared with the inner diameter of the section I8. The co-operating jaw II is preferably formed from a forging and serrated jaw pieces 20 are welded, brazed, soldered, riveted, or otherwise secured to the components Ill and II. The activating lever I2 is also formed from a channelshaped stamping having the sides 2| and the back 22 and the channel, of course, opens toward the associated handle I0. As described generally above, the co-operating jaw II and handle III are pivotally secured together by the rivet 23, the 00- operating jaw II and the activating lever I2 by the rivet 24, and the link I3 and the lever I2 by the rivet 25.
The slidable anchorage of the handle end of the link I3 is effected through a pin 26 extending through aligned apertures in the end of the link I3 and a pair of arms 21 lying on either side of the link and within the section I8 of the handle I0. The outer surfaces 28 of the arms 21 (see Figures 3 and 4), conform, more or less, to the inner surface of the cylindrical section [8 and as the link I3 extends downwardly through the slot I9, the associated arms and link are slidable longitudinally of the handle. A similar pin 29 extends through aligned apertures adjacent the forward ends of the arms 21 and through the interleaved flattened rearward end 3! of the adjusting bolt 3 I. The bolt 3 I, in turn, is threadedly engaged in the adjusting nut I4 which is mounted in and extends through oppositely disposed slots 32 in the sides ll of the handle II). The link I3 is formed with a forward cam surface 33 which engages the back 22 of the lever I2 to limit the successive opened positions of the plier jaws which vary with the relative longitudinal positions of the pin 26; and a rearward cam surface 34 which comes into similar engagement with the back 22 just after the toggle linkage has passed the dead center or looking position when the jaws are in the various closed positions. A coil spring 35 is secured between the pin 36 mounted in the co-operating jaw II and the back It of the housing I5 and urges the co-operating jaw II in a 4 counterclockwise direction with respect to the handle In.
The device is assembled by pivotally securing together the handle I ti and the jaw II and the lever I2 and the jaw II by the rivets 23 and 24, respectively. The adjusting bolt SI and the link I3 are then placed between the arms 27 and the pins 26 and 29 are inserted through the respective aligned apertures in these elements. This subassembly is then introduced into the cylindrical section It through the opening 31 at the rear end of the section and slides forwardly until the forward end of the bolt 3| comes in contact with the nut I4 which is held centered in the slots 32. The nut It is rotated until it threadedly engages the bolt 3I drawing the subassembly forwardly. The pins 26 and 29 are, of course, held in engagement with the arms 21 and the flattened end 30 and the link I3 by being enclosed within the cylindrical section I4 and the link I3 extending through the slot I5 prevents relative rotation of the subassembly components and the handle IE3. The jaws are now opened to their full extent and the spring 35 is slipped within the housing I5 and over the pin 36 into bearing on the back I6. The link I3 may then be brought between the sides 2I of the lever I2 and the apertures therethrough aligned and the components pivotally secured together by the rivet 25. This completes the assembly of the tool.
A modified form of the anchoring arrangement is shown in Figure 5 in which the link is indicated as I I3. Instead of using the arms 21 of the first construction, their place is taken by a single, substantially cylindrical member I21 having a vertically disposed, longitudinal slot I28 terminating short of the ends of the member I21. A pin I26 extends across the slot I28 adjacent its rearward end and passes through the enlarged aperture I29 in the link II3 securing it in Cal place. The end I30 of the link H3 is formed to correspond with the rear end I3I of the slot I 28 and the clearance between the aperture I29 and the pin I26 is sufficient to permit the engagement of the surfaces i3U and I3I when the toggle linkage is loaded so that the stress is taken directly by the member I21 rather than through the pin I26. The rearward end I32 of the adjusting bolt I3I is threaded into the tapped hole I33 or otherwise secured to the forward end of the member I27.
It is believed that the foregoing description will serve both as a complete disclosure of the precise structure of the tool and as an explanation of its advantages in use and the ease with which it may be assembled in manufacture. It will be apparent that the tool may be managed with much more dexterity than the conventional adjustable toggle pliers and that the same mechanical advantage can be obtained in a device having much smaller over-all dimensions. The operating structure is entirely shielded and the tool may be readjusted in use without the necessity of the operator shifting his grip or using his other hand. The parts are fixedly secured together rather than being urged into engagement by spring pressure. The tool presents a much neater appearance and there are no projecting parts presenting possibility of injury to the user.
The invention claimed is:
1. In an adjustable toggle pliers, a handle hav ing a jaw at the forward end thereof and a hollow handgrip at the rearward end thereof, a co-operating jaw member pivotally secured to said handle adjacent the forward end thereof, anac- I: tivating lever having its forward end pivotally secured to said jaw member, a toggle link pivotally secured at its forward end to said lever and having its rearward end slidably received within said handgrip, a bolt having its rearward end secured to said rearward end of said toggle link and extending forwardly therefrom within said handle, a nut rotatably mounted transversely of said handle with a portion thereof extending outwardly of said handle and threadedly engaging 1 said bolt, and spring means resiliently urging said jaw member and said jaw on said handle apart.
2. The structure of claim 1 which is further characterized in that said handle is substantially channel-shaped in cross section and the handgrip portion thereof is formed with a restricted inwardly opening slot through which said toggle link extends.
3. The structure of claim 1 which is further characterized in that said handle is substantially channel-shaped in cross section, oppositely disposed slots are formed in the walls of said channel forwardly of said handgrip, said nut being mounted in said slots.
4. The structure of claim 1 which is further characterized in that said handle is substantially channel-shaped in cross section, said handgrip portion thereof is formed with a restricted inwardly opening slot through which said toggle link extends, transversely spaced arms slidably retained within said handgrip and pivotally secured at their rearward ends to opposite sides of said link, said arms being secured to the rearward end of said bolt adjacent its rearward end, whereby rotation of said nut with respect to said handle will occasion the advance or retraction of said arms within said handgrip to change the effective position of said link.
5. The structure of claim 1 which is further characterized in that said lever is at least partially substantially channel-shaped in cross section, said link having a cam surface forwardly of its point of pivotal attachment to said lever engaging the bottom of said channel to limit the distended position of said jaws, said link having a cam surface rearwardly of its point of attachment to said lever engaging the bottom of said channel immediately after said link has passed the dead center position in which said jaw and said jaw member are in relatively closed position, said cam surfaces being so formed as to enter said engagement in successive positions of adjustment of said slidably mounted end of said link.
6. The structure of claim 1 which is further characterized in that said handgrip portion thereof is substantially cylindrical in cross section and is formed with a restricted inwardly opening slot through which said link extends, an anchor member slidably retained within said handgrip and having a slot aligned with said handgrip slot terminating forwardly of the end of said member, means pivotally securing said link to said anchor member within said slot therein adjacent the rear end of said slot, said pivotal securing means having sufficient clearance to permit the rear end of said link to engage the rear end of said anchor member, said bolt being secured to the forward end of said anchor member.
7. In an adjustable toggle pliers, in combination, a handle having a jaw at the forward end thereof and a handgrip at the rearward end thereof, a co-operating jaw member pivotally scoured to said handle adjacent the forward end thereof, an activating lever having its forward end pivotally secured to said jaw member laterally of said pivotal attachment between said jaw memer and said handle, a toggle link pivotally secured to said lever rearwardly of said pivotal attachment between said lever and said jaw memher and extending rearwardly into said handgrip through a restricted slot opening inwardly in said handgrip, attaching means slidably retained within said handgrip by said restricted slot and pivotally secured to the rearward end of said lever therewithin, a bolt having its rearward end secured to said attaching means and extending forwardly therefrom within said handle, a transverse slot in said handle forwardly of said handgrip, a nut rotatably mounted within said transverse slot and having portions extending transversely of the body of said handle, said nut threadedly engaging said bolt, and spring means forwardly of said nut resiliently urging said jaw and said jaw member apart.
8. In an adjustable toggle pliers, a handle having a jaw at the forward end thereof and a hollow handgrip at the rearward end thereof, a co-operating jaw member pivotally secured to said handle adjacent the forward end thereof, an activating lever having its forward end pivotally secured to said jaw member, a toggle link pivotally secured at its forward end to said lever and having its rearward end slidably received within said handgrip, a bolt having its rearward end secured to said rearward end of said toggle link and extending forwardly therefrom Within said handle, a nut threadedly engaging said bolt and rotatably mounted transversely of said handle and restrained against movement longitudinally of said handle with a portion of said nut extending outwardly of said handle through a. slot therein.
JOHN T. SPENCER, JR. ETTORE GIRARDELLO.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,573,722 Logan Feb. 16, 1926 2,112,192 Geddes Mar. 22, 1938 2,280,005 Petersen Apr. 14, 1942 2,312,947 Westman Mar. 2, 1943 2,385,654 Seashore Sept. 25, 1945 2,397,239 Brown Mar. 26, 1946