Patent ID: 7497272
Filing Date: 2009-03-03
Classification: B25D

Abstract:
1. A hand held power tool, comprising: a machine housing ( 10 ), a tool fitting ( 12 ) integrated therein, the tool fitting ( 12 ) being drivable in a rotatory manner by an electric motor ( 19 ) in a first mode of operation and being non-rotatably fixable to the machine housing ( 10 ) in a second mode of operation, a duty-type switch ( 20 ) and a coupling element ( 21 ) displaceable to activate the modes, and an actuating element ( 22 ) that includes a displacement of said coupling element, wherein the actuating element includes an electrical actuator ( 23 ) and an electronic control unit ( 24 ) that controls the actuator ( 23 ), wherein a manually operated, electric switch ( 36 ) for turning the machine on and off is located on the maching housing ( 10 ), electric switch ( 36 ) being designed such that it must be manually held against the force of a reset spring ( 38 ) in the mode with tool fitting ( 12 ) being driven in a rotating manner, wherein an electromagnet ( 39 ) controlled by the control device ( 24 ) is assigned to the electric switch ( 36 ), the magnetic force of which is greater than the spring force of the reset spring ( 38 ), and the control unit ( 24 ) is configured such that it supplies an excitation current for the electromagnet ( 39 ) assigned to the electric switch ( 36 ) with a tool fitting ( 12 ) installed on the machine housing ( 10 ).