Patent ID: 6227085
Filing Date: 2001-05-08
Classification: B23B,Y10T

Abstract:
A gyration/reciprocating action switching mechanism comprising an output shaft, a first clutch mounted on said output shaft, a second clutch mounted inside said first clutch and coupled to said output shaft, a torsional force adjustment mechanism mounted on a speed reduction mechanism of a power hand tool, and a gyration control device, wherein:said first clutch is comprised of a first axle sleeve sleeved onto said output shaft, a second axle sleeve embedded inside a front tube of the speed reduction mechanism of the power hand tool, a first cam fixedly mounted on said output shaft, a second cam mounted in said second axle sleeve, and a retainer, said second axle sleeve comprising a plurality of equiangularly spaced front notches, said first axle sleeve comprising a plurality of recessed portions equiangularly spaced around the periphery at a front end thereof and extended in axial direction, a rear extension axially extended from a rear end thereof, and a plurality of retaining portions respectively engaged into the front notches at said second axle sleeve, said first cam being stopped at the rear extension of said first axle sleeve and aimed at said second cam;said second clutch is arranged between the first axle sleeve of said first clutch and said output shaft, the second clutch comprising an axle bearing, an axle sleeve, a coil spring, and a gasket;said gyration control device is coupled to said torsional force adjustment mechanism, the gyration control device comprising a center through hole, which receives said output shaft, and a plurality of coupling rods respectively engaged into the recessed portions on the first axle sleeve of said first clutch; androtation of said gyration control device to a lower limit position forces the retaining portions of the first axle sleeve of said first clutch into engagement with the front notches on the second axle sleeve of said first clutch to shorten a stroke of said output shaft, thereby causing said first cam to be retainably disengaged from said second cam by a spring force of the coil spring of said second clutch, thereby enabling the coil spring of said second clutch to be compressed to force said first cam into contact with said second cam and to let said output shaft be reciprocated upon pressing of said output shaft against an object.