Patent ID: 7329173
Filing Date: 2008-02-12
Classification: B24B

Abstract:
1. A grinding machine comprising: a machine base; a grinding unit, said grinding unit comprising a motor fixedly mounted on said machine base and a grinding wheel coupled to and rotatable by said motor; and a workpiece driving unit, said workpiece driving unit comprising a first guide screw pivotally mounted on said machine base, a first slide coupled to said first guide screw and movable forwards/backwards in X-axis direction upon rotation of said first guide screw in clockwise/counter-clockwise direction, a locating block mounted on said first slide, a second guide screw pivotally mounted in said locating block and extending in Y-axis direction in parallel to the center axis of said grinding wheel, a second slide coupled to said second guide screw and movable forwards/backwards in Y-axis direction upon rotation of said second guide screw in clockwise/counter-clockwise direction, a first knob fixedly fastened to one end of said first guide screw for operation by the user to rotate said first guide screw, a second knob fixedly fastened to one end of said second guide screw for operation by the user to rotate said second guide screw, a rack horizontally rotatably mounted on said second slide, a bracket pivotally mounted on said rack and locked thereto by a screw bolt for allowing said bracket to be turned about Y-axis after loosened said screw bolt, an axle sleeve fixedly mounted on said bracket, and a tool holder mounted in said axle sleeve, said tool holder comprising a barrel mounted in said axle sleeve, a shaft, said shaft having a longitudinal groove on the periphery thereof, a chuck mounted on one end of said shaft, a screw mounted in said barrel and threaded into the longitudinal groove of said shaft to secure said shaft to said barrel for allowing axial movement of said shaft relative to said barrel and rotary motion of said shaft with said barrel, a drive bevel gear pivotally mounted on said bracket, a driven bevel gear fixedly mounted on a rear end of said barrel and meshed with said drive bevel gear, a hand wheel for rotating said drive bevel gear, an universal joint pivotally mounted in one end of said shaft, an extension axle mounted in said universal joint, and an eccentric wheel coupled between said driven bevel gear and said extension axle such that when operating said hand wheel to drive said drive bevel gear to rotate said driven bevel gear and said barrel, said shaft and said chuck are simultaneously rotated with said barrel, and at the same time said eccentric wheel is alternatively rotated forwards and backwards to reciprocate said extension axle, said shaft and said chuck.