US2197128A - Quick acting clamp - Google Patents

Description

p 1940- J. H. HARRISON Y 2,197,128

QUICK ACTI-NG cum? Filed April 10, 19:59

INVENTOR 6 17 15 BY Q... a) I I ATTORNEY Patented Apr. 16,1940

UNITED" STATES PATENT OFFICE This invention relates to hand actuated clamps, the principal object of my invention'being to provide a tool ofthis nature so constructed that it may be operated, "either to provide a [clamping hold or to release-such hold, with one hand.

1 Another object is to provide a toolhaving a reciprocating or oscillating operating or control member and ,to arrange the operating parts in connectionwith such member that successive movements of the same in'the same direction alternately effect the clamping and release of the of times the tool may be engaged with or released from the work during the performing of the necessary operations thereon. V

The tool is thus particularly adapted for repe- 25 titious use on work of a given thickness, as when holding plates and the like together for welding or drilling at different points in their extent, or in any case where repeated but intermittent clamping oi the work is desirable. I

A further object of the invention is to produce a simple device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fullyappear by a perusal of the following specificationv and claims.

In the drawing similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a side elevation of the tool with the jaws in clamping position.

Figure 2 is a fragmentary section showing the control cam in the position occupied in Fig. 1.

Figure 3 is a similar view showing the position of the control cam when the jaws are released or relatively separated.

Figure 4 is a fragmentary sectional plan on line 4-4 of Fig. 1.

- Referring now more particularly to the characters of reference'on the drawing, the body of the tool comprises a pair of transversely spaced side ears I which depend from one end of and are rigid with a handle 2, and .are also rigid with a boss 3 disposed ahead of the handle and ears I above the latter.

Adjustably threaded through the boss so as to be disposed substantially at right angles to the handle is a screw 4 provided at its upper end, above the head, with a suitable cross handle 5 and with a clamping nut l to engage the head.

The lower end of the screw is provided with a jaw element 1.

Projecting forwardly from between the ears I at their lower end is an arm 8, carrying an upstanding iaw element 9 facing to and adapted to aline when in operation, with the element I. This arm is pivoted intermediate its ends on a pin l mounted on the members I, and the upper surface of the portion of said arm between the ears is formed as a flat ledge ll. Turnably mounted between the ears I above the arm on a shaft i2 is a cam i3 having a plurality of evenly spaced high and low points H and L respectively thereabout. Preferably the cam is in the form of a hexagon with its corners flattened somewhat. When any high point engages ledge H in proper radial relation, the arm 8 is obviously swung upward at its outer end, and the jaw elements I and 9 are then alined as shown in Fig. 2. When a low point engages the arm, the outer end of the latter will of course be lowered and the jaw'elements correspondingly separated as shownin Fig. 3. A spring H of suitable form acts against the arm to hold the same against the cam, and causes ledge H to follow and always engage either the high or low points of the cam as the latter rotates.

It is to be understood that the radius of all the high points is the same, and this is also true of the low points. The jaw elements 1 and 9 will therefore be the same distance from each other when any high point of the cam is riding ledge I I. Such rotation of the cam, to control the setting of arm 8 and jaw element 9 relative to the fixed jaw element 1, is controlled by the following means:

The shaft l2 projects at both ends outwardly from ears I, and fixed on one projecting portion is a ratchet wheel l having the same number of teeth as the total number of high and low cam points, and which face rearwardly at the top of the wheel. Pivoted on the shaft l2 adjacent wheel I5 is an arm l6, carrying a pawl I! to engage the teeth of wheel l5 at the top. This arm rearwardly of ears I is bent laterally and then extends as a handle l8 directly under handle 2. A spring 19 between the handles tends to hold them spread, and approach of the handles is limited by a stop 20 onone handle.

The are of swinging movement of the handle l8, and of the pawl, is not less than the arc of spacing between adjacent ratchet teeth, and less than the spacing between two teeth. The stop 20 is set so that when the handles are at their limit of approach, either a high or low cam point is exactly centered on the ledge H.

The shaft 12 is mounted with a close running fit, but in order to prevent retractive rotation thereof when the pawl is dragging over the ratchet wheel, said shaft (which is in the form 01' a bolt) is provided on the projecting end thereof opposite the ratchet wheel, with a nut and spring washer unit 2| engaging the adjacent ear I.

In operation the nut B is first loosened and the screw 4 retracted so that when the handles are spread and the jaw element 9 lowered, the plates P or other work to be clamped may project between the jaw elements. The handles are then brought together, bringing jaw element 8 toward the work and the screw 4 is then advanced until the work is firmly clamped between the jaw elemerits. The lock nut 6 is then set to hold the screw 4 against movement. To release the clamping hold, it is only necessary to allow handle is to drop away from handle 2, and then again bring the handles together. The drop of handle it does not affect the position of the cam, since the pawl merely drags over the ratchet wheel. The opposite movement of said handle however again imparts rotation to the rachet wheel, shifting the same from a high to a low engaging point: The arm '8 thus drops, moving jaw element '9 away from and releasing the work. Two more oscillating movements of handle l8 again brings a high cam point into operation, and since all the high points are the same arcuate distance from the axis of rotation of the cam, the jaw elements will then always be set at the same spacing from each other and the work will be clarn'ped with the same effectiveness with each return of the jaw elements to clamping position. The handles are arranged so that even when fully spread, they may be readily gripped in one hand, and thus the operation of the tool, through its recurring clamping and releasing movenients, can be conveniently eifected with one hand, leaving the other hand free for other uses.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forthherein. 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 myinvention, what I claim as new and useful and desire to secure by l.etters.Patent isi.

1. A clamping tool comprising a body having a handle projecting from one end thereof, a fixed jaw elementmounted on the body at the end thereof opposite the handle, a movable jaw element mounted on the body in opposed cooperating relationship to the fixed jaw, a member mounted for oscillation on the body and means between "said'rnember and the movable jaw to move the lattertoward the fixed jaw with alterriate movements of the'me'mber in'one direction and to move"said movable jaw away from the fixed jaw with the intermediate movements of the member in said one direction.

2. A tool as in claim 1, in which said member includes a handle positioned relative to the first named. handle to be engaged in common by one hand 0.1: an operator.

3. A clamping tool comprising a body having ahandle projecting from one end thereof, a'fixed jaw element mounted -on the body, at the end thereof opposite the handle, a movable jaw element disposed in opposed cooperating relationship to the fixed jaw, an armon one end of which the movable jaw element is fixed, means mount-' ing the arm lntermediate its'ends' on. the body for rocking movement, another handle pivoted.

on the body in cooperating relationship to the first handle for oscillating movement toward or from the same and means between said other handle and the arm to rock the same in one direction with alternate oscillating strokes in one direction, and to cause said arm to rock in the other direction with the intermediate strokes of the other handle in said one direction.

4.. A tool as in claim 3, in which said last named means includes a rotary cam mounted on the body and engaging the arm, said cam being formed with a plurality of high and low points about its circumference.

' v5. A clamping tool" comprising a body having a handle projecting from one end thereof, a fixed jaw element-mounted on the body at the end thereof opposite the handle, a movable jaw element disposed in opposed cooperating relationship to the fixed jaw, an ar'm onone end of which the movable jaw element is fixed, means mounting the arm on the body for rocking moyement, av rotary cam mounted at a pointthereon' such asto rock the arm with rotation of the cam, said cam being formed with a plurality of alternating high and low points, the high points being 'all equidistant from the axis of the cam and means to intermittently rotate the cam predetermined arcuate amounts.

6. A clamping tool comprising a body having a handle projecting from oneend thereof, a"'fixed jaw element mountedon the bodyat the end thereof opposite the handle; a movable jaw element disposed in opposed cooperating relationship to the fixed jaw, an arm on one endf'of which th movable jaw element is fixed, means mounting the arm intermediate its ends on the body for. rocking movement, a rotary ,c'am mountedonthe body and engaging thearm on the 'same sidebut adjacent the end, thereof opposite that from which the jaw element projects, said cam being formed with a plurality of evenly spacedand alternating high and low points, another handle pivoted on the body in common with but turnable relative to the cam, a ratchet. wheel fixed with the cam and the arcuate spacing of whose teeth is the same as that between adjacent cam points and a pawl mounted on said other handle and engaging the ratchet wheel; said other handle being arranged for oscillating movement sufficlent to advance the ratchet wheel the full distance between adjacent, teeth only with each movement of said handle in one direction.

'7. A tool as in claim 6, in which said other handle is disposed relative to thefirst handle so as to be engaged in commpnby, one hand of an operator; the pawl being positioned to advance the ratchet wheel with movement of said other handle toward the first handle.

8. A tool as in claim 6, in which said other handle is disposed relative to the first handle so as to be engaged in common by 'one hand of an operator; the pawl being positioned to advance the ratchet wheel with movement of said other handle toward the first handle, andmeans to limit the movement of said other handle toward the first handle;"'the cam'being 'disposed relative to said other handle when at itslimit of move- JOHN H. HARRISON.

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