Patent ID: 6464017
Filing Date: 2002-10-15
Classification: B25B

Abstract:
A transmission mechanism for pneumatic tool, comprising a casing in which a main body, a sleeve seat, a sleeve, and a spring are sequentially assembled from bottom to top of said casing, and a transmission shaft axially mounted in and projected from a top of said casing to extend through an oil-retaining shaft sleeve via a washer; said washer being provided at one side facing toward the top of said casing with an axially projected boss portion; said casing having a top portion that is axially extended beyond said washer and is provided along an inner peripheral surface close to a top edge thereof with a locating groove for receiving a C-shaped retaining ring therein; and said C-shaped retaining ring firmly bearing against one side of said washer around said boss portion to locate said transmission shaft in place in said casing; whereby any impact force acted on said main body via said spring is isolated by said C-shaped retaining ring to protect said main body against deformation, and said washer is protected from overly tight contact with said oil-retaining shaft sleeve to avoid undesired friction, noise, heating, and reduced torque output of said transmission mechanism.