Actuation apparatus for power tool

A hammer drill operable in a first mode of operation and a second mode of operation, the hammer drill comprising:

• a housing;
• a motor disposed in the housing and supplyable with electric current via a power circuit;
• a transmission for driving a working member of the hammer tool in response to rotation of the motor;
• an on/off switch located in the power circuit and selectable to one of an on position and an off position, and in the on position the on/off switch conducts electric current to the motor and in the off position the on/off switch does not conduct electric current to the motor;
• a trigger disposed on the housing to enable a user to position the on/off switch,
• a mode control switch disposed in the housing and adapted to enable a user to select one of the first mode of operation and the second mode of operation;
• a mode selection sensor providing a first signal indicating which mode of operation of the hammer drill has been selected;
• a lock-on switch located in the power circuit and in electrically parallel arrangement to the on/off switch, the lock-on switch selectable to one of an closed position and an open position, and in the closed position the lock-on switch conducts electric current to the motor and in the open position the lock-on switch does not conduct electric current to the motor;
• a control circuit for positioning the lock-on switch, the control circuit receiving the mode selector sensor first signal, and
• wherein, when the first mode of operation is selected, a first depression of the trigger will cause the control circuit to position the lock-on switch in the closed position and will maintain the lock-on switch in the closed position after release of the trigger, and a second depression of the trigger will cause the control circuit to position the lock-on switch in the open position.

An actuation apparatus for a power tool having a housing, a motor with a rotary output shaft disposed in the housing, drive means for driving a working member of the tool in response to rotation of said rotary output shaft, and a trigger disposed on the housing to enable activation of said motor, the actuation apparatus comprising:

• switching means for enabling a user to select between a hammer mode of said tool, a drilling mode of said tool and/or a hammer and drilling mode of said tool;
• detection means for providing at least one signal indicating which mode of operation of the tool has been selected;
• and
• control means for controlling operation of the motor in response to at least one said signal, such that in at least one first predetermined mode of operation said motor is operated by a first depression of the trigger and remains activated until deactivated by a second depression of the trigger, and in at least one second predetermined mode of operation, said motor is only activated while the trigger is depressed.