Abstract: A transducer arrangement for torque and/or angular displacement measurement, especially in power screwdrivers, operates in accordance with the eddy current principle. The transducer arrangement is constructed as a self-contained structural unit having its own transducer casing which is connected by appropriate coupling and connecting parts to the housing of the power screwdriver and to the driving and driven members of the screwdriver. A torsionally deformable member, especially shaft, is interposed between the driving and driven members, being connected thereto for joint rotation therewith. When torque is applied to the deformable member, its end portions are angularly displaced relative to one another. Two slotted members, especially sleeves, are respectively connected to the end portions of the deformable member for joint angular displacement therewith, and they influence the magnetic field in the vicinity of the deformable member in proportion to their relative angular displacement.

Abstract: A pneumatic tool includes a fluid motor with a rotor and passages for connecting the rotor with a source of fluid under pressure. A normally open valve is interposed in the passages and movable to a closed position in which it interrupts the flow of fluid to the rotor. An actuator is located on the rotor and operative, in response to the rotor exceeding a predetermined speed of revolutions, to move from a neutral into an actuating position in which it engages the valve and moves the same to the closed position thereof.

Abstract: A drive is mounted in a housing and an output shaft is coupled with the drive to be rotated by the same and is connectable with a fastener to be driven. An arrangement is provided for deactivating the drive when the torque acting on the output shaft exceeds a predetermined selectable level. This arrangement includes a plurality of surface portions which surround the axis of rotation of the shaft and which each of which is continuously inclined radially and circumferentially of the shaft. A plurality of transmitting members is mounted for torque-dependent shifting in direction radially of the axis, and biasing springs urge the members radially outwardly against respective ones of the surface portions.

Abstract: An electric motor of the tool has a drive shaft and in turn drives an output shaft by means of a gear transmission. A mechanical arrangement senses the torque of the drive shaft of the motor and varies the supply of electrical energy to the motor in dependence upon changes in the torque.

Abstract: A safety claw clutch wherein the adjacent end faces of driving and driven rotary clutch elements have alternating claws and recesses and the driven clutch element is biased axially against the driving clutch element by a spring. The bottom surfaces in the recesses of the clutch elements make a first acute angle with a plane which is normal to the common axis of the clutch elements and the front surfaces of claws of the driving clutch element (and hence the rear surfaces of claws of the driven clutch element) make with such plane a second acute angle which is larger than the first acute angle. The top surfaces of the claws are parallel to the respective bottom surfaces.

Abstract: A sanding plate is mounted in a housing with freedom of gyratory motion, and a rotatable eccentric shaft is journalled in the housing and connected with the plate for imparting the motion to the latter. A pneumatically powered rotary piston engine is mounted in the housing and connected with the shaft for rotating the same. The rotary piston of this engine has an imbalance which compensates for the imbalance resulting from the motion of the plate.