Abstract: A device for screwing and unscrewing bolts and screws uses a motor-driven screwdriving tool, which is preferably used in the track region of railroad facilities. The device makes it possible to screw and unscrew screws, nuts and bolts reliably and effectively, preferably in the context of railroad use. The appliance is intended to have a low weight and a high output over long periods of use, can be operated with one hand, is specifically pre-oriented to the various applications and has a modular construction. To this end, the device has a central rib which serves as a receptacle for all of the attachments and fittings to be installed in a modular manner.

Abstract: A power screwdriver overload prevention means (100), which is arranged between an input drive part (110) and an output drive part (102, 121) and which interrupts the transmission of torque between the input drive part (110) and the output drive part (102, 121) when a threshold torque is exceeded, is characterized in that the input drive part (110) has at least one ring of balls (130) that is arranged in a rotationally fixed manner in the input drive part, in that the output drive part (102, 121) has at least one ring of balls (140; 141, 142) that is arranged in a rotationally fixed manner in the output drive part (102, 121), and in that the ring of balls (130) that is arranged in the input drive part (110) is spring-preloaded via the ring of balls (140; 141, 142) arranged in the output drive part (102, 121) such that the balls (130) of the input drive part (110) are located in each case between two balls (140; 141, 142) of the output drive part (102, 121) and thus transmit a torque, and such that, when the th

Abstract: The invention relates to a circuit arrangement for operating a hydraulic torque wrench or similar, comprising a piston-cylinder unit (18) that can be controlled at a predetermined pressure by a pump (11). Said arrangement is characterized in that the piston-cylinder unit (18) can be controlled by the pump (11) by means of a proportional valve (12) which acts both as a reversing unit between the forward and return travel and as a pressure control valve.

Abstract: A device for screwing and unscrewing bolts and screws uses a motor-driven screwdriving tool, which is preferably used in the track region of railroad facilities. The device makes it possible to screw and unscrew screws, nuts and bolts reliably and effectively, preferably in the context of railroad use. The appliance is intended to have a low weight and a high output over long periods of use, can be operated with one hand, is specifically pre-oriented to the various applications and has a modular construction. To this end, the device has a central rib which serves as a receptacle for all of the attachments and fittings to be installed in a modular manner.

Abstract: A method for producing a toothing on an in particular round workpiece, wherein the teeth are produced by a shaping method using a tool which moves along a path which is controlled by a lifting cam and in the case of which an exchange movement that runs substantially in the radial direction of the workpiece follows a downward movement which runs in the axial direction of the workpiece and serves to produce the tooth flanks, wherein the exchange movement is superimposed with a downward movement such that a curved path is produced during the exchange, is characterized in that the relative rake angle ?rel of the tool (200) does not fall below a minimum rake angle ?min which corresponds to the rake angle ? of the tool (200), the rake angle ? being reduced by the angle ? between the longitudinal axis of the workpiece and the direction vector of the tool movement.

Abstract: A power screwdriver overload prevention means (100), which is arranged between an input drive part (110) and an output drive part (102, 121) and which interrupts the transmission of torque between the input drive part (110) and the output drive part (102, 121) when a threshold torque is exceeded, is characterized in that the input drive part (110) has at least one ring of balls (130) that is arranged in a rotationally fixed manner in the input drive part, in that the output drive part (102, 121) has at least one ring of balls (140; 141, 142) that is arranged in a rotationally fixed manner in the output drive part (102, 121), and in that the ring of balls (130) that is arranged in the input drive part (110) is spring-preloaded via the ring of balls (140; 141, 142) arranged in the output drive part (102, 121) such that the balls (130) of the input drive part (110) are located in each case between two balls (140; 141, 142) of the output drive part (102, 121) and thus transmit a torque, and such that, when the th

Abstract: The invention relates to a circuit arrangement for operating a hydraulic torque wrench or similar, comprising a piston-cylinder unit (18) that can be controlled at a predetermined pressure by a pump (11). Said arrangement is characterised in that the piston-cylinder unit (18) can be controlled by the pump (11) by means of a proportional valve (12) which acts both as a reversing unit between the forward and return travel and as a pressure control valve.

Abstract: A housing (100) for a hydraulic unit is characterized by a housing wall (101) which is closed on all sides and in which at least one inlet opening (110) and at least one fan (121), which can be operated independently of the hydraulic unit (400), are arranged.

Abstract: The invention relates to a device for producing precise tightening torque for screw connections including the combination of a torque multiplier (100) and a torque wrench (200) which is adapted to the torque multiplier and calibrated therewith. The invention also relates to a method for calibrating the type of device.

Abstract: The invention relates to a power screwdriver (10) comprising a motor (12) and a control circuit (22) which switches the motor (12) off by means of a switch-off signal (s_Stop) when it reaches a preset desired torque value (Md_Soll), and a supporting arm (18) which absorbs energy during screwing. The invention is characterized by a voltage limiting circuit (46) that limits the motor voltage (u_Mot) occurring on the motor (12) when the energy stored in the supporting arm (18) of the motor (12), which is driven as the generator and rotates counter to the direction of drive, is dissipated, to a predetermined limiting voltage (u_Lim). The limiting voltage (u_Lim) is fixed in such a manner that the motor (12) is capable of rotating without counter-torque counter to the direction of drive when operated in the generator mode and that yet no inadmissible overvoltages occur.