Abstract: A hydraulic impulse screwdriver includes a control circuit, a drive shaft, a compressed-air motor having a motor shaft, a compressed air inlet, and an outlet, a striker having a pressurizing cylinder chamber, the striker connected to the outlet of the compressed-air motor for impulse-like driving of the drive shaft, a shut-off device for torque-dependent interruption of the compressed-air inlet to the compressed-air motor, the shutoff device including a servoelement seated in the motor shaft of the compressed-air motor and forming a pressure-carrying link between the pressurizing cylinder chamber of the striker and the shut-off device, by which a torque-related signal is fed to the control circuit, which control circuit interrupts the compressed-air inlet to the compressed-air motor when a specified torque limit value is reached, a bending bar in the shut-off device that is arranged in cooperation with the servoelement, the bending bar being provided with a transducer to determine a bending moment dependent o

Abstract: A compressed-air screw or bolt tightener having a driving motor which drives a driving shaft for a screwing or tightening tool is disclosed. The motor is operated by compressed air and a control valve for switching the compressed-air supply to the screw or bolt tightener on or off. A pressure-regulating valve is used to regulate the kinetic energy of the screw or bolt tightener.

Abstract: A hydro-impulse screwing device comprises a rotary drive motor, a power source for the motor, a drive shaft, a pulsating hydraulic drive connecting the motor to the shaft and a power cut-off for the motor. The load at which the power cut-off functions is adjustable. The tool has a borehole extending through the length of the shaft, a conduit for conducting hydraulic fluid from the drive to the borehole, a valve in the borehole movable from a closed position to an open position in response to hydraulic pressure corresponding to a predetermined load to allow hydraulic pressure from the drive to actuate the power cut-off, a biassing element in the borehole for biassing the valve toward a closed position against the hydraulic pressure, wherein the force of the biassing element is adjusted at the end of the drive shaft to change the load at which the power cut-off operates.

Abstract: This invention relates to a rotary impulse screwing device which generates only one pulse per rotation of the output shaft. Two main and two additional lamellas are adjustably positioned in the output shaft. The two main lamellas seal at a minimum of two times per rotation of the output shaft. The two additional lamellas are adjusted independently via separate recess tracks to ensure that each additional lamella seals at only one point per rotation of the output shaft. The independently articulated additional lamellas further ensure that the load on the output shaft bearing is symmetrical on non-impulse points of rotation.

Abstract: In reversible compressed air rotary motors for compressed air tools, particularly for wrenches, it is known to discharge the waste air radially from the casing of the motor, which results in a considerable nuisance, in particular as regards noise. Furthermore, due to the close positioning of the compressed air inlet and air outlet, poor efficiency is achieved. To avoid those drawbacks in a rotary sliding vane motor having an elliptical working chamber, the rotor end over on the inlet side is rotatably mounted, and air outlet means is arranged axially and lies in both the clockwise as well as in the antic-clockwise direction or rotation of the rotor relative to the major semi-axis of the elliptical working chamber. Thus by rotating the end cover to one or other of its limit positions, the outlet means communicate with different pairs of passageways.