Patent ID: 6484814
Filing Date: 2002-11-26
Classification: B25D

Abstract:
An electrical hand operated tool driving device for producing an at least partially impacting movement of an axially elongated tool (11) driven by an air striking mechanism (2) with a no-load stroke disconnection of the impact in the absence of an axial counter-pressure over the tool (11), said air striking mechanism including a driving mechanism (3), having a range of rpm, a piston (4) connected to said driving mechanism (3), a free piston (6) spaced in the axial direction of said tool (11) from said piston (4), an anvil (7) between said free piston (6) and said tool (11), said free piston (6), said anvil (7) and said tool (11) having a no-load stroke position (9) in the event of a no-load stroke, a housing enclosing said no load stroke position (9), a sensor (14) within said housing for scanning said no-load stroke position, a control unit (15) connected to said sensor (14) for evaluating said sensor whereby, in the event of a no-load stroke, the rpm of the driving mechanism can be lowered to a previously fixed rpm by said control unit (15).