Patent ID: 7237459
Filing Date: 2007-07-03
Classification: B25B

Abstract:
1. A ratchet screwdriver comprising: a handle; a shaft fixed to said handle and including an imaginary plane extending axially through an axis of said shaft, a circumferential face, two first pawl-receiving grooves formed respectively and symmetrically in said shaft on two sides of said imaginary plane, two second pawl-receiving grooves formed respectively and symmetrically in said shaft on two sides of said imaginary plane, and two spring-receiving recesses formed in said shaft on two sides of said imaginary plane, respectively, and each communicating with one of said first pawl-receiving grooves and one of said second pawl-receiving grooves, each of said first and second pawl-receiving grooves having a groove opening formed in said circumferential face, and a groove bottom opposite to said groove opening, said groove opening being wider than said groove bottom in an angular direction; a ratchet wheel unit sleeved rotatably on said shaft, and including a wheel portion having a plurality of teeth disposed around said circumferential face, and a tool-coupling portion projecting from said wheel portion opposite to said handle; a pawl unit including two first pawl plates disposed respectively in said first pawl-receiving grooves, and two second pawl plates mounted respectively in said second pawl-receiving grooves, each of said first and second pawl plates having a retaining end and a swingable end extending respectively to said groove bottom and said groove opening of one of said first and second pawl-receiving grooves, said swingable end of each of said first and second pawl plates being swingable within a limited angle defined by said groove opening so as to move between a first position, where said swingable end engages one of said teeth, and a second position, where said swingable end is released from said one of said teeth; two spring elements disposed respectively in said spring-receiving recesses, each of said spring elements having two opposite ends urging respectively said swingable ends of one of said first pawl plates and one of said second pawl plates to move to said first positions of said swingable ends; and a switching ring sleeved on said shaft between said handle and said wheel portion, and having a plurality of actuators each moving a respective one of said first and second pawl plates to said second position.