Abstract: A hand-held power tool, particularly hand-operated angle grinder has a device housing having a motor housing receiving an electric drive, a gear head arranged at one end of the motor housing and having a projecting drive spindle for a tool, and a handle arranged at another end of the motor housing and having a switch strip for switching the electric drive on and off, at least one of the handle and the gear head forming a rotatable housing part and being rotatable relative to the motor housing around a longitudinal axis of the motor housing. A manually actuated positioning device fixes the rotatable housing part in at least two different rotational positions, while the motor housing being provided with a central bearing neck, the rotatable housing part being provided with a rotating cross which is received on the bearing neck so as to be rotatable and secured against axial displacement, the positioning device being formed to cause a positive-locking engagement between the motor housing and the rotating cross.

Abstract: In an electric hand machine tool, particularly an angle grinding machine, for the purpose of ergonomic handling the handle, together with the switch bar, is designed to be rotatable, relative to the tool mounting on the gear head (11). For the rapid, problem-free changing of the position of the handle relative to the tool mounting, the handle (12) can be locked against rotation on the motor casing, containing the electric drive, in at least two turned positions by a manually operable locking device, and can be clamped on the motor casing by a manually operable clamp device. In a preferred embodiment the locking device (40) and clamp device are coupled together by constraint and are operated simultaneously by means of a single tightening lever.

Abstract: A clamping device for clamping a protective hood on a clamping collar of an angle grinder has, a clamping strap which has ends and is clampable together in the region of the ends, a clamping lever having one end and being pivotable at the one end about a pivot axis in respect of one of the ends of the clamping strap, and a transmission member which is engaged by the clamping lever and which engages at a distance from the clamping lever another of the ends of the clamping strap and during clamping brings the ends of the clamping strap nearer to one another. The transmission member, the clamping member, and the ends of the clamping strap form a toggle-lever device which during clamping contracts the clamping strap in the region of the ends of the clamping strap in a manner essentially free of any bending moment.

Abstract: A device for axially clamping a disc-shaped tool on a flange of a driven spindle with a threaded end, includes a clamping nut, a clamping disc supported on the clamping nut for biasing the disc against the flange and connected with the clamping nut for joint rotation therewith and axial displacement relative thereto, and supporting bodies arranged between the clamping nut and the clamping disc. An actuating member is located between the clamping nut and the clamping disc, and rolling bodies are displaceable along guide paths defined by guide tracks of the supporting bodies and guide track means of the actuating member for radially loading the supporting bodies. An insert member is supported between the clamping nut and the clamping disc and includes a plurality of stops projecting into the guide paths.

Abstract: A clamping fixture for detachably fixing a tool to a driven spindle and comprising a flange for applying a clamping force to the tool and axially displaceable relative the driven spindle and coupled to the driven spindle for transmitting a torque thereto, a supporting element for securing the flange against axial displacement relative to the spindle to prevent the flanges from applying a damping force to the tool, the supporting element comprising an annular nut member displaceably mounted on the spindle adjacent an end of the flange which is remote from the tool, and having a right-hand coarse thread to be screwed onto the threaded portion with an external coarse thread of the spindle, a torsion spring for coupling the annular nut member to the flange, and a locking device for preventing rotation of the annular nut member upon actuation of the locking device.

Abstract: A protective hood assembly for a grinding machine comprising a protective hood having a predetermined size corresponding to the predetermined diameter of the grinding disc; a fastening receptacle attachable to the grinding machine housing and having a shoulder for receiving the protective hood; and a member for securing the protective hood on the shoulder and including a locking portion, the shoulder of the fastening receptacle having an opening for receiving the locking portion upon fastening of the securing member on the shoulder, at least one of shape, arrangement, number, and size of the locking portion and the opening corresponding to the locking portion, being selected in accordance with the predetermined size of the protective hood in such a way as to prevent mounting on the fastening receptacle protective hoods having a size exceeding the predetermined size of the protective hood.

Abstract: An electric power machine, particularly an angle grinding tool is provided with a centrifugal overspeed protecting device including a fly weight in the form of a severing blade which interrupts a power supply conduit when the rotary speed of the machine is excessive. The protective device includes a cylindrical housing attached face to face to the shaft of the electric motor. The severing blade is in the form of a quadrangular frame defining a center opening. The cylindrical housing is provided with a diametric through bore of a rectangular cross-section matching the frame-like severing blade. A blind bore of a circular cross-section is coaxially superposed on the rectangular through bore and its upper part is formed with inner thread for receiving a setting screw. A helical tensioning spring is inserted in the center opening of the frame-like severing blade and rests on the bottom of the blind bore to urge the centrifugal severing blade against the setting screw.

Abstract: A torque limiting power screwdriver includes a housing in which there is supported for rotation and axial displacement a screwdriver spindle. A transmission transmits power from a motor to the screwdriver spindle. A torque overload coupling and a separating coupling are interposed in the transmission, being operative for interrupting the transmission of torque from the motor to the screwdriver spindle. The separating coupling is coupled and uncoupled in response to axial displacement of the screwdriver spindle between its coupling and uncoupling positions. The axial movement of the spindle is accomplished by a trigger movably mounted on the housing and connected by a Bowden cable or a lever transmission to the spindle. The spindle is connected by an axially movable coupling with an output member, especially with a bevel gear transmission accommodated in an angular head housing portion. A switching trigger is used to energize and de-energize the motor.