Patent ID: 6112830
Filing Date: 2000-09-05
Classification: B25D

Abstract:
A drill hammer having an air cushion percussion device, the hammer comprising:a housing having a drill tool axis;an energizing bushing disposed in said housing concentric with respect to a drill tool axis, said energizing bushing defining a cavity enclosing the air cushion;a percussion piston disposed in said housing for back and forth motion within said cavity;a nutating disk disposed in said housing and cooperating with said energizing bushing to displace said energizing bushing back and forth in a direction of the drill tool axis for compressing and decompressing said air cushion to drive said percussion piston back and forth;a rotation element disposed in said housing parallel to and at a distance from the drill tool axis for rotation to drive said nutating disk;a weight disposed in said housing to cooperate with said nutating disk, at a side of said nutating disk lying diametrically across from said energizing bushing; andguidance means disposed in said housing to cooperating with said weight for restricting said weight to move linearly back and forth parallel to the drill tool axis in response to action of said nutating disc.