US2720805A

US2720805A - Slidable side jaw wrench

Info

Publication number: US2720805A
Application number: US444858A
Authority: US
Inventors: Brynge Per Gunnar
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-07-21
Filing date: 1954-07-21
Publication date: 1955-10-18
Anticipated expiration: 1972-10-18

Description

Oct. 18, 1955 P. G. BRYNGE SLIDABLE SIDE JAW WRENCH Filed July 21, 1954 INVENTOR. 2 PER GUNNAR BRYNGE KULJ Z FIG.

ATTORNEY United States Patent SLIDABLE SIDE JAW WRENCH Per Gunnar Brynge, Fannalund, Enkoping, Sweden Application July 21, 1954, Serial No. 444,858

2 Claims. (Cl. 81-165) The present invention relates to adjustable Wrenches of the type in which an adjustable jaw is movable in the wrench head and may be displaced toward and from a fixed jaw formed in the wrench head by means of an adjusting screw which is rotatably mounted in the wrench head and engages a toothed guide cam in the lower portion of the adjustable jaw, said guide cam being movable in a corresponding groove in the jaw head.

Said cam, the length of which is comparatively great, must move as frictionless as possible in the groove to permit an easy adjustment of the movable jaw. It was found, however, that when the movable jaw is hardened, the cam tends to become deformed, in that it becomes warped during hardening, so that it obtains a slightly arcuate form, whereby the cam will tend to jam in the groove and obstruct or entirely prevent displacement of the movable jaw. Therefore, it has heretofore been necessary after hardening of the movable jaw to subject the cam to a grinding operation, which is both timeconsuming and difficult to perform, since it is not easy to determine accurately the points where grinding shall take place.

It has been found that said disadvantage may be removed in a highly satisfactory manner by forming the guide cam in an intermediate portion thereof with a reduced thickness along a major part of the periphery of a cross-section. It was found that by this means the tendency of the guide cam to become warped during hardening is reduced considerably, and in addition any deformation can no longer be of such a magnitude that the unobstructed movability of the cam is impaired. This shape of the guide cam has the additional advantage that the machining by reaming before hardening is more easily performed, since the reduced thickness of the cam in its 'ice intermediate portion provides a particle-separating clearance, so that the reaming action is improved along the entire length of the cam.

On the appended drawing, a wrench embodying the principles of this invention is shown in Figure 1 in perspective with the parts shown separated, while Figure 2 shows the adjustable jaw in another position, also in perspective.

Referring to the drawing, the numeral 1 denotes the fixed head of the wrench with the fixed jaw 2 formed thereon. The numeral 3 denotes the adjustable jaw, which is formed in its lower portion with a flat web portion 4, and a thicker, e. g. rounded rod-shaped guide cam 5 contiguous with the web. The cam 5 has teeth 6 in its lower portion, said teeth being adapted to cooperate with the adjusting screw 7, which is freely rotatable on a pin 8 in the opening 9 of the wrench head 1.

According to this invention, the cam 5 is in an intermediate portion formed with a reduced thickness along a major part of the periphery of a cross-section so as to form a recess 10. Due to this recess the tendency of the cam to warp during hardening is reduced, as has been established by experiments, and even if any deformation occurs, this can never be so large that a cam, which prior to hardening fits in the groove, can after hardening give rise to jamming in the groove, which Would require an additional finishing treatment of the cam. According to a further feature of the invention it is suitable to make the flat web portion 4 somewhat thicker at its ends so as to form guiding lugs 11, which assist in preventing deformation of the cam during hardening.

Having now particularly described the nature of my invention and the manner of its operation what I claim is:

I. An adjustable wrench, in which an adjustable jaw is movable in the wrench head and is displaceable towards and from a fixed jaw formed in the Wrench head by means of an adjusting screw, which is rotatable in the wrench head and engages a toothed guide cam on the lower portion of the movable jaw, said guide cam being displaceable in a groove in the jawhead and being formed in an intermediate portion thereof with a reduced thickness along a major portion of the periphery of a crosssection.

2. A Wrench according to claim 1, in which a web portion between the jaw and the guide cam is formed somewhat thicker at its ends so as to form guiding lugs.

No references cited.