Self-tightening wrench

Abstract

The invention provides a self-tightening wrench, and relates to the field of mechanical assembly and maintenance tools. The self-tightening wrench comprises a body, wherein the body is provided with a central through hole; a plurality of radial guide grooves are formed in the body in the circumferential direction; a clamping jaw is hinged to the interior of each guide groove through a pin shaft, and the clamping jaws can swing around the pin shafts; a driving piece is rotatably arranged above the body through an annular guide rail mechanism; the driving piece comprises an end cover and a round rod fixedly connected to the bottom of the end cover, and the bottom end of the round rod is fixedly connected with an eccentric block; and when the driving piece is rotated, the outer peripheral surface of the eccentric block abuts against and drives the top ends of the clamping jaws. The self-tightening wrench not only can adapt to severe abrasion of edges and corners of fasteners and realize rapid and reliable occlusion, but also can keep stable and non-slip in the operation process like a standard sleeve, and realizes efficient and safe continuous torque transmission.

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