Abstract: An optical control is disclosed which is particularly suitable for application as a switching device, regulating device or sensor device for a power tool. At least two optical waveguides are provided one of which being configured as a transmitting waveguide is coupled to a light source, a second one of which being configured as a receiving waveguide cooperating therewith is coupled to an evaluation circuitry. Both waveguides cooperate with a control element that is movable at least between two positions in which light signals of different magnitude are transmitted from the transmitting waveguide into the receiving waveguide.

Abstract: An optical control is disclosed which is particularly suitable for application as a switching device, regulating device or sensor device for a power tool. At least two optical waveguides are provided one of which being configured as a transmitting waveguide is coupled to a light source, a second one of which being configured as a receiving waveguide cooperating therewith is coupled to an evaluation circuitry. Both waveguides cooperate with a control element that is movable at least between two positions in which light signals of different magnitude are transmitted from the transmitting waveguide into the receiving waveguide.

Abstract: The invention discloses a power tool having a motor adapted to drive a tool, comprising at least one switching element, coupled with a controller, for actuation of the motor, the controller being configured so that the motor can be switched on for driving the tool only when the at least one switching element is activated several times in a predetermined way, or when at least two switching elements are activated simultaneously or in a predetermined way in succession, there being provided at least three operating modes, namely an inoperative mode, in which the motor is out of operation, a working mode in which the motor is driven for driving the tool, and an intermediate mode, in which the user is signaled that further activation of a switching element is needed for transferring the motor to its working mode.

Abstract: A power tool is disclosed which comprises a hosing within which a motor is received for driving a tool. At least one switch is received on said housing and can be operated via an elastic touch surface from outside the housing. The switch is part of a signaling circuit which is coupled to a power circuit for activating the motor when said signaling circuit is activated.

Abstract: A circuit for a series motor for a power tool is disclosed, wherein reliable switching is achieved by means of two electronic switches, without the use of a mechanically disconnecting switch. To this end, two electronic switches, preferably triacs, are preferably connected in series to each other, the voltage drop across the triacs being continuously monitored by a monitoring circuit. A check for faults can be carried out before switching on the power tool. Alternatively, a fusible cutout can be tripped by means of a protective switch connected in parallel thereto.

Abstract: A circuit for a series motor for a power tool is disclosed, wherein reliable switching is achieved by means of two electronic switches, without the use of a mechanically disconnecting switch. To this end, two electronic switches, preferably triacs, are preferably connected in series to each other, the voltage drop across the triacs being continuously monitored by a monitoring circuit. A check for faults can be carried out before switching on the power tool. Alternatively, a fusible cutout can be tripped by means of a protective switch connected in parallel thereto.

Abstract: A power tool is disclosed which comprises a hosing within which a motor is received for driving a tool. At least one switch is received on said housing and can be operated via an elastic touch surface from outside the housing. The switch is part of a signaling circuit which is coupled to a power circuit for activating the motor when said signaling circuit is activated.

Abstract: A retarded electric motor designed as a series motor or an asynchronous motor having a squirrel cage rotor. A valve is provided for switching between motor operation and braking operation. During motor operation the motor is operated in a known configuration as series motor or as asynchronous motor. If configured as a series motor, the valve (S1, S2, S3) allows to bypass the armature and to operate the motor as an externally excited direct current generator when switching into braking operation. If configured as an asynchronous motor, a switch is utilized to disconnect at least two field windings from mains. A valve is utilized to excite the motor externally from mains with a pulsating direct current during braking.

Abstract: The invention discloses a power tool having a motor adapted to drive a tool, comprising at least one switching element, coupled with a controller, for actuation of the motor, the controller being configured so that the motor can be switched on for driving the tool only when the at least one switching element is activated several times in a predetermined way, or when at least two switching elements are activated simultaneously or in a predetermined way in succession, there being provided at least three operating modes, namely an inoperative mode, in which the motor is out of operation, a working mode in which the motor is driven for driving the tool, and an intermediate mode, in which the user is signaled that further activation of a switching element is needed for transferring the motor to its working mode.

Abstract: A retarded electric motor is disclosed which may be designed as a series motor or an asynchronous motor having a squirrel cage rotor. A valve means is provided for switching between motor operation and braking operation. During motor operation the motor is operated in a known configuration as series motor or as asynchronous motor. If configured as a series motor, the valve means (S1, S2, S3) allows to bypass the armature (12) and to operate the motor (10) as an externally excited direct current generator when switching into braking operation. If configured as an asynchronous motor, a switch is utilized to disconnect at least two field windings from mains. A valve means is utilized to excite the motor externally from mains with a pulsating direct current during braking.

Abstract: An optical control is disclosed which is particularly suitable for application as a switching device, regulating device or sensor device for a power tool. At least two optical waveguides are provided one of which being configured as a transmitting waveguide is coupled to a light source, a second one of which being configured as a receiving waveguide cooperating therewith is coupled to an evaluation circuitry. Both waveguides cooperate with a control element that is movable at least between two positions in which light signals of different magnitude are transmitted from the transmitting waveguide into the receiving waveguide.