Patent ID: 6089330
Filing Date: 2000-07-18
Classification: B25D

Abstract:
A device for transmitting pulsed axial percussions to a drill (12), comprising a housing (2) one end of which is releasably connectable with a housing (3) of a hand-held rotary drill; rotating transmitting means (7, 9) rotatably supported within the drill housing (2) and operatively connected with a rotatable spindle (4), which projects from the rotary drill housing (3), for joint rotation therewith; a chuck (11) provided at an end of the device housing (2) opposite to the one end for receiving the drill (12); a reciprocating hammer member (15) movable into an abutting engagement with a trailing end of the drill (12); and a hammer mechanism (17-20; 21-24) arranged within the device housing (2) for imparting pulsed axial percussions to the hammer member (15),wherein the hammer mechanism (17-20, 21-24) comprises a hammer (18, 21) connectable with the rotation transmitting means (7, 9) for effecting periodical axial reciprocating movements for transmission of the pulsed axial percussions to the hammer member (15),wherein the hammer mechanism is formed as a cushioned cam hammer mechanism comprising a cam ring (17) rotably supported in the device housing (2) and driven by the rotating hammer member (15), the cam ring (17) having cam means operatively connected with complementary cam means provided on the hammer (18) for periodically axially displacing the hammer (18) against a return force of a spring (20), upon being rotated relative to the hammer (18), andwherein the cam ring (17) is rotably supported in the device housing (2) without a possibility of an axial displacement therein, and wherein the return force of the spring (20) is adjustable.