Patent ID: 6062113
Filing Date: 2000-05-16
Classification: B25B

Abstract:
A pneumatically operated screw driver connected to a compressed air source for driving a screw held by a screw band into a workpiece, the screw band detachably holding a plurality of screws arrayed in line with a constant interval, and the screw band having one side where each head of each screw is exposed, and having another side from which each threading portion of each screw extends, the screw driver comprising:a housing formed with an compressed air inlet connected to the compressed air source;a pneumatic motor disposed in the housing and selectively communicated with the compressed air source, the pneumatic motor being driven by a compressed air supplied from the compressed air source;a drive bit disposed in the housing and rotationally driven by the pneumatic motor, the drive bit having a tip end engageable with the head of the screw held in the screw band;a casing supported to the housing and extending in the axial direction of the drive bit;a slide mechanism slidably disposed in the casing, the slide mechanism being slidable upon pressing the housing onto the workpiece, the slide mechanism having a front portion provided with a screw feed mechanism movably holding the screw band for feeding each screw held by the screw band to a position adjacent the tip end of the drive bit and in axial alignment therewith in accordance with the sliding movement of the slide mechanism, the head of each screw being pressed by the tip end of the drive bit, and the another side of the screw band being supported by the slide mechanism; anda mechanism for facilitating a separation of the screw from the screw band, the facilitating mechanism comprising:a sub-piston cylinder disposed at the housing and extending in a direction parallel with the drive bit;a sub-piston slidably movably disposed in the sub-piston cylinder and having a front end, a sub-piston chamber being defined by the sub-piston cylinder and the front end;a piston rod connecting the slide mechanism to the front end of the sub-piston; andmeans for introducing a compressed air into the sub-piston chamber for urging the slide mechanism rearwardly.