US1266233A - Plate-lifting clamp. - Google Patents

Description

A. w. ECKERSON.

PLATE LlFTlNG CLAMP.

APPLICATION FILED JULY 12.1917.

1,266,233. Patented May 14, 1918.

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ALBERT W. ECKERSON, OF PORTLAND, OREGON.

PLATE-LIF'IING CLAMP.

s ecification of Letters Patent.

Patented May 14., 1918.

Application filed J'u1y 12,1917. Serial No. 180,170. 1

To all whom it may concern: I

Be it known that I, ALBERT W. ECKERSON, a citizen of the United States,-residing in the city of Portland, county of Multnomah, and State of Oregon, have invented certain new and useful Improvements in Plate-Lifting Clamps, of which the following is a specification.

My invention relates to lifting clamps and more particularly to a lifting clamp adapted for use with derricks, and the like, for liftand heavy iron and steel plates.

One of the principal objects of my invention is to provide a device of the character referred to, capable of lifting plates of Various thicknesses without injury thereto; that is, a device in which the clamping dogs, or members, register with each other on opposite sides of the plate to be lifted, whereby to avoid any shearing engagement with the plate. In other words, I provide a body member adapted to set down over the edge of the plate, with clamping dogs, or clamping members, on both sides of the body, the clamping dogs, or members, on each side operating 1n the same plane.

In order to more clearly explain my invention I have illustrated one practical embodiment thereof in the accompanying sheet of drawings, which I will now describe.

Figure l is a side elevation of one of my lifting clamps, with a plate to be lifted indicated in dot and dash lines; and

Fig. 2 is an edge view thereof.

Referring now more in detail to the drawings, 1 designates a body member provided in its lower end with an open receivin slot 2, and at its upper end with a closed slot 3. Pivotally mounted on opposite sides of the body 1, and also at opposite sides of the receiving slot 2, are. two pairs of clamping dogs 4-4 and 5-5, pivoted to the body, as at 4 and 5*, each of said dogs having a plateengaging toe portion, as 4 and 5. Mount- I ed on opposite sides of the upper end of said body 1, are two head plates 66, with a bolt 7 connecting them through the slot 3 in the upper end of the body 1. A lifting clevis 8 is also attached by means of said bolt 7, to the head plates 6-6, as clearly shown. Operating links 9-9, are connected at their upper ends to the opposite ends of the head plates 66. as at 1010, and at their lower ends said connecting links are connected, as at 1111, between outer ends of the clamping dogs H and 5-5. Thus it will be seen that as the cle vis 8 and the head plates 66 are lifted, they operate through the connecting links 9-9, to rock the clamping dogs 4.-4= and 55, so that their clamping toes 4 and 5 approach each other and clamp therebetween the plate P, indicated in broken lines.

Attention is called to the fact that there is a clamping dog 1, and a clamping dog 5, on each side of the body 1, and that these 00- cupy the same plane and engage the plate to be lifted at points directly opposite each other, whereby there is no tendency to a shearin action on the plate, which there would be if said clamping dogs occupied adjacent planes. It will also be noticed that the weight tends to tighten the clamping effect of the dogs thereon. The clamping dogs automatically grip the plate as soon as the lifting operation commences, and they release the plate as soon as the clevis 8 and the head plates 6-6 are allowed to move downwardly in the slot 3, relative to the body 1.

While I have shown the preferred embodiment of my invention, I do not limit it to the details as here shown, except as I may be limited by the hereto appended claims.

I claim:

1. A. lifting clamp of the character re ferred to comprising an integral body having an open slot in its lower end and a guide slot in its upper end, clamping dogs pivotally connected to the side of said body at opposite sides of said open slot, a lifting member moving in the guide slot at the upper end of said body, and operating connections from said lifting member to said clamping dogs, whereby as said lifting member moves upwardly said clamping dogs are moved toward each other in the same plane, substantially as described.

2. A plate lifting clamp comprising a body having an open slot in its lower end adapted to setover the edge of a plate, two pairs of clamping dogs pivoted to the opposite sides of said body at opposite sides of said slot, the clamping dogs on the same side of the body operating in the same plane toward each other, a lifting member movably connected with said body, and operating connections therefrom to said clamping dogs. whereby as said lifting member is moved upwardly said clamping dogs are simultaneously operated, substantially as described.

3. A plate lifting clamp comprising a body having an open slot in its lower end adapted toflset over the edge of a plate to be lifted and a slot in its upper end, a pair of clamping dogs pivotally connected to each side of said body With clamping portions adapted to be named toward each other in register with said open slot a pair of head plates mounted on opposite sides of the upper end of said body and connected through theslot therein, a lifting elevis connected to said head plates, and eoiniecting links connesting the opposite ends of said head plates Copies of this patent may be obtained for five cents with the outer ends of said clamping dogs, whereby as said lifting clevis and said head plates are lifted the clamping dogs at opposite sides of said body are moved toward each other at opposite sides of said open slot, substantially as described.

Signed at Portland, Multnomah county, Oregon, this 6th day of July, 1917 ALBERT W. ECKERSON. In presence of I. M. GRIFFIN, J. C. STRENG.

each, by addressing the Commissioner of Patents,

Washington, D. C.

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