Robert Boschgmbh

Manfred Kirn

Friedrich Hornung

Gunter Schaal

David Matzo

Erich Borst

Joerg Dehde

Gerd Hahn

Werner Grammer

Joachim Schadow

Manfred Bleicher

Justus Lamprecht

Arnim Fiebig

Ernst Kraenzler

Ernst Dreher

Michael Holzer

Reinhold Stroezel

Alfred Hettich

Joerg Moessner

Gerhard Kraemer

Andreas Hoelderlin

Klaus Klingenstein

Kurt Metzger

Manfred-Wilhelm Staebler

Herbert Faerber

Meinhard Eule

Leon Bujalski

Klaus Guenther

Christian Hermes

Dieter Schafer

Karl Treyz

Bernard Eicher

Alex Gawron

Guenter Schaal

Joerg Ullrich

Karl Garatwa

Karl-Ernst Kober

Volker Lasch

An electric motor has a switching device, a driving circuit connectable to a voltage supply through the switching device and having a drive shaft, a mechanically acting braking device for braking the drive shaft when disconnecting the electric motor from the voltage supply, a rotor serving to generate torque and acted upon by a mechanical braking force when switching off the voltage supply, at least one radially displaceable part which applies the braking force and is magnetizable and acted upon by an electromagnetic releasing force which is directed opposite to the braking force and is greater than the braking force, and a stator having an axial slit which is overlapped by the part, and at least one shorted turn arranged in an area of the slit.

Electric motor

Manually driven machine

Manual machine tool with tool holder and appropriate tool

A series-wound motor, wherein, for braking purposes, the polarity of the armature of the motor is reversed for the opposite direction of rotation. The current supply for the motor is maintained until the armature comes substantially to a standstill and subsequently, the current supply to the motor is interrupted. The braking time is controlled in dependence upon operating parameters. For example, the braking time can be controlled by a predetermined time constant for the interruption of the current supply. To prevent running in the opposite direction, a reversal preventing device can be provided.

Series-wound motor with a braking element

Hand held power tool with locking rotatable appendage

Motor-driven hand-held machine tool

Armature for high-speed electric motors force-ventilated in air

Power hand tool with a gearbox casing with sealing washer

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

To provide sufficient magnetization to the field of a series motor when the series motor is to be operated in dynamic braking mode, with a dissipating resistor or short circuit element (4) connected across the armature (5), a circuit connection is established between one of the main terminals of the motor through the series field to supply a minimum magnetization current, at least when the motor operates under dynamic braking conditions, typically a few to up to 15% of no-load current of the motor. This is sufficient magnetization so that, even in larger motors where remanent magnetism of the field structure is insufficient, reliable dynamic braking can be ensured. A switch (S; S.sub.1, S.sub.2) selectively connects the motor armature for motor drive or running operation and dynamic braking operation. The magnetization current supply can be through a capacitor, resistor, or resistor-capacitor combination, which can be permanently connected across the power supply (10, 11) of the motor, or connected in circuit only when the switch (S, S.sub.2) changes the motor into dynamic braking operation.

Electrical series motor with dynamic braking circuit

Clamping device for axially tightening a tool, in particular a disc

Clamp device for axially clamping a tool, particularly a disc

A device for releasable mounting of a disk-shaped tool on a working spindle, comprises two flange members arranged to abut against the tool, supporting elements arranged to support one of the flange members against its axial displacement on the working spindle, wherein the supporting elements are releasable so as to unload the one flange member from a clamping pressure and formed as rolling bodies, arranged between the working spindle and the one flange member and displaceable transversely to their supporting direction into a deviating space.

Device for releasable mounting of a disk-shaped tool

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. Such configuration of the claws and recesses insures that the force which tends to reengage the clutch elements when the driving clutch element rotates relative to the driven clutch element upon disengagement of the clutch is a small fraction of the force which normally maintains the claws of the driving clutch element in the recesses of the driven clutch element and vice versa because the claws of the driving clutch element cannot enter the recesses of the driven clutch element.

Ratchet type safety claw clutch

Growing community of inventors

Stuttgart, Germany

Manfred Kirn