US9567A - Improved screw-wrench - Google Patents

Description

UNITED STATES PATENT OEEICE.

GEORGE B. READ, OF NEW YORK, N. Y.

IMPROVED SCREW-WRENCH.

Specification forming part of Letters Patent No. 9,567, dated February 1, 1S53.

invented a new and Improved lVrench; and.

I do hereby declare that the following is a full, clear, and exact description of the same,

. reference being had to the annexed drawings,

making a part of this specification, in which- Figure l is a side view of the wrench. Fig. 2 is also a side View of the same with the stationary jaw bisected, in order to show the pawl which catches into the rack on the shank of the movable jaw. Fig. 3 is a section showing the rack released from the pawl, in order that the movable jaw may be properly adjusted, so that a bolt-head, nut.1 or other article designed to be turned by the wrench may be secured or iitted snugly between the two jaws.

Similar letters and figures of reference indicate corresponding parts in cach of the several figures.

The nature of my invention consists in having the shank of t-he adjustable jaw pass through a recessin the stationary j aw, which is attached by a pivot to the end of the wrenchstock. The shank of the adjustable jaw is provided with a rack, into which a pawl, attached to the end of the wrench-stock, catches. By this arrangement, as will be hereinafter shown, the two jaws as the handle of the wrench is turned tend to bind or press rmly upon the nut, particularly upon the outer corners of it, and thus the jaws are prevented from slipping around the corners of the nut.

The adjustable jaw is brought against the nut -by freeing the pawl from the rack, which is done by merely pressing the outer corner of the stationary jaw and the handle and stock of the wrench toward each other, as will be hereinafter shown. By thus freeing the pawl from the rack the shank of the adjustable jaw maybe moved within the recess in the stationary jaw.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction and the manner in which it is used, or operated.

A represents the stock of the wrench, to which stock is affixed the handle B.

C is a jaw attached by a pivot a to the end of the stock A. The jaw C has a square recess through it, through which recess the shank D of the jaw F. passes or works. On one of the sides of the shank D there is a rack b, into which a pawl F, attached to the end of the stock A, catches. (See Fig. 2.) A spring g bears against the pawl F and keeps it in the rack. the stock A. j

By referring to Fig. 2 the operation and object of the arrangement will be readily understood.

It will be seen that by drawing or turning the handle B in the direction indicated by the arrow 2 the two jaws E C will be forced toward each other, because the stock A is a lever having its fulcrum at a, and the pawl F is attached to the end of the stock to a projection c. Consequently when the handle-is moved or turned in the direction of the arrow 2 the pawl F will force or press the shank D and jaw E in the direction of the arrow 3, and the jaw C will move in the direction of arrow 4. Therefore the nut d (see dotted lines) has the two jaws E O pressing irmly upon two of its sides as the handle and stock of the wrench are moved or turned. The pressure ofthe jaws will be the greatest at the outer corners 5 6 of the nut G, because the pivot or fulcrum a is at the corner of the jaw C, and the line of pressure will be in the direction indicated by the dotted line d. Thus the jaws areprevented from slipping around the corners of the nut as the wrench is turned.

The jaws are adjusted to the nut in the following simple manner: The corner e of the jaw C and the end f of the stock A are pressed toward each other in the direction indicated by arrows l l. (See Figs. 2 and 3.) By doing this the pawl F is thrown from the rack b, as seen in Fig. 3, in consequence of the projection 7L acting against'it, and consequentlythe shank D may be moved in the recess and the jaw E moved nearer to or farther from the jaw O, so that nuts of different sizes may be operated upon and grasped firmly by the jaws.

The jaw E,I term the adjustable jaw, as it is moved,when being adjusted to a nut, independently of the jaw C, and the jaw C, I term a stationary jaw, as it has no motion communicated to it except that given it by turning or moving the handle of the wrench.

I do not claim having the jaw E attached to a shank and the shank passing through a recess in the jaw C independent of the mode One end of that spring is attached to of operating the jaws, for the above device, differently modified, is employed in various Wrenches now in use; but

Vhat I claim as new, and desire to secure by Lett-ers Patent, is-

The arrangement of the several parts, as herein shown and deseribed--viz., the jaw C, being attached by a pivot a to the stock A, and said jaw C having a recess through it, through which recess the shank D of the adjustable jaw E passes, the shank D being provided with a rack l), into which a paWl F, at-

tached to the end of the stock, catches, said pawl being kept into the rack b by the spring g, by which arrangement the two jaws E C are forced against the sides of the nut as the handle of the wrench is turned and the jaws made to bear or bind harder upon or near the corners 5 and 6 of the nut, thus preventing the jaws from slipping around it.

G. B. READ. Witnesses:

A. D. MUNN, S. H. WALES.

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