Robert Boschgmbh

Manfred Stabler

Walter Barth

Fritz Schadlich

Winfried Helm

Erich Borst

Karl-Heinz Braunbach

Thomas Muller

Friedrich Hausslein

Protective hood for grinding machines, particularly angle grinders, and

Clamping fixture for detachably particular a disc

Clamping fixture for axially clamping a tool in place, in particular a

A clamping fixture for axially clamping a tool, on a flange of a driven spindle and comprising a clamping nut having an internal thread to be screwed on an end portion with an outer thread of the driven spindle, a clamping member arranged between the tool and the clamping nut for transmitting an axial clamping force to the tool upon tightening of the clamping nut, a manually operable adjustable member freely rotatable relative to the end portion of the driven spindle, and a gearing for gear-coupling the adjusting member to the clamping nut and gear-coupling the clamping nut to the clamping member.

Eccentric grinder

An eccentric grinder is provided with a device for changing a grinding motion. The grinder includes a grinding disc eccentrically positioned on a driving shaft and supporting an internal and an external toothed crowns which are brought to a rolling motion on respective external and internal toothed crowns supported on the housing of the grinder. The toothed crowns supported on the housing are axially displaceable by a handle provided externally of the housing. Three various grinding motions for coarse, medium and fine grinding can be obtained by the drive of the grinder.

Eccentric grinder with a device for changing a grinding motion

A protective element for a hand-held power tool with a rotary tool, such as a grinding disk, a circular saw, or the like, has a protective member with cut-outs having increased portions, an additional member connectable with the protective member, and connecting elements for connecting the additional member to the protective member and including a plurality of holding screws having heads extending through the increased portions of the cut-outs and engageable behind the protective member, wherein the increased portions have the shape of the plan view of the screw heads and are provided at the same end of the elongated cut-outs, and a locking projection is provided near at least one increased portion in the path of the screw head of the screw sliding in the respective cut-outs.

Protective element for hand-held power tool

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 machine tool, especially a hand-held power tool, comprises a tool spindle and a clamping element turnably mounted on the spindle, in which the turnable clamping element is arrestable during rotation of the spindle for clamping or releasing a tool mounted thereon to thereby make a separate implement for preventing rotation of the clamping element during clamping or releasing the tool on the spindle unnecessary. In a special embodiment of the present invention the clamping or releasing forces during change of the tool are mechanically applied and the turning moment during clamping of the tool is limited to a predetermined value.

Machine tool, especially a hand-held power tool with a turnable clamping

A protecting hood assembly for use in a motor-driven hand tool such as grinder or circular saw. The assembly includes a hood having a pair of openings, each being formed with a narrowing portion of a squared cross-section and a widened portion forming a slot, a pair of vertically positioned supporting members each having a longitudinal slit and a couple of bolts having each a peripheral portion inserted into said slit and said opening. The widened portion of the opening receiving the bolt is formed with a size in a horizontal direction being larger that a diameter of the peripheral portion of the bolt and a size in a vertical direction being smaller that said diameter to facilitate the installation of the bolt into the hood opening upon assembling and to provide a reliable clamping of said bolt in assembly after insertion thereof.

Growing community of inventors

Leinfelden-Echterdingen, Germany

Manfred Stabler