Robert Boschgmbh

Erich Borst

Fritz Schadlich

Manfred Kirn

Manfred Stabler

Manfred-Wilhelm Staebler

Gunter Schaal

Steffen Wunsch

Walter Barth

Heinz Walz

Winfried Helm

Gunter Zilly

Bernhard Eicher

Kurt Metzger

Dieter Schafer

Karl Treyz

Fritz Kuettner

Willi Sproesser

Anton Reiter

Dieter Schaefer

Karl-Ernst Kober

Volker Lasch

Brigitte Hertell

Bernard Eicher

Guenter Schaal

Hand held power tool with locking rotatable appendage

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.

Electric hand machine tool, and rotatable handle or appendixes

Clamping device for clamping a protective hood on the clamping collar of

Clamping device for axially clamping of a tool, especially a disc

Clamping fixture for detachably fixing a tool, in particular a disc

Protective hood for grinding machines, particularly angle grinders, and

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. When the rotary speed of the shaft and thus of the housing exceeds a predetermined value the severing blade is displaced by centrifugal force out of the rectangular through bore and severs a conduit in the power supply circuit for the motor whereby the compressed biasing spring acts as a buffer. The setting screw adjusts the distance on the center of gravity of the severing blade from the axis of rotation of the motor shaft and thus determines the value of the limit rotary speed.

Electric power machine with protection against overspeed

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. The trigger and the switching trigger can be combined into a trigger unit, thus making possible one-hand operation. The trigger and switching trigger are so constructed and arranged that they force the succession of energization of the motor and coupling of the separating coupling during the commencement of operation, and the succession of uncoupling the separating coupling and de-energization of the motor during the termination of operation.

Torque limiting power screwdriver

Growing community of inventors

Leinfelden-Echterdingen, Germany

Erich Borst