Abstract: An end effector for a robotic sanding system includes a sanding head including a sander configured to sand a surface of a workpiece. A motor is operatively coupled to the sander. The motor is configured to rotate the sander to sand the surface of the workpiece. The motor includes a first central longitudinal axis. A coupler is configured to removably secure the end effector to an attachment interface of an arm of the robotic sanding system. The coupler includes a second central longitudinal axis. The first central longitudinal axis is offset from the second central longitudinal axis. One or more sensors are coupled to the sanding head. The one or more sensors are configured to detect presence of a metal within the predefined range.

Abstract: A glass polishing device has a casing adapted for operative engagement with the exterior surface of a powered drill motor. The casing includes a handle extending from a second side opposite an opening in an opposite first side thereof from which a handle of the engaged drill motor projects. A triggerable fluid supply is coupled to the casing and projects fluid to a tool or a section of glass being resurfaced by the tool.

Abstract: A system for attaching a handle such as an extension pole to a power tool such as a hand sander includes a collar, a pressure plate, front and back pairs of vibration absorbing spacers, and a handle holder. The collar has a contact area and two projections extending from the contact area, and the a plate fits onto the projections so that the plate and the contact area of the collar define a space for mounting of a tool. The handle holder extends between the projections and is between the first and second pair of vibration absorbing spacers. A tightening structure may press the plate toward the contact area and compress the first and second pairs of vibration absorbing spacers toward the handle holder.

Abstract: In order to provide a working machine capable of suppressing an increase in size, a working machine that rotates a working tool with motive power of a motor includes a transmission mechanism that transmits a rotational force of the motor to the working tool, a front case in which the transmission mechanism is disposed, a holding tool that is attached to the front case so as to protrude from an outer surface of the case and is gripped by a worker, and an attaching hole which is provided in the front case and to which the holding tool is attached, and the attaching hole penetrates the front case in plan view intersecting with an axis that is a rotation center of the working tool.

Abstract: The present invention relates to a floor grinding apparatus (100) with a housing (110) having an interior space (111) open to one side, a carrier plate (120) rotatably mounted in the interior space (111) for receiving abrasives, and drive unit (130) adapted to rotate the carrier plate (120), the housing (110) having an inner dust sealing ring (112) with at least one recess (115), wherein the inner dust sealing ring (112) divides the interior space (111) into an inner portion (113) and an outer portion (114), and wherein the carrier plate (120) is disposed in the inner portion (114), at least one extraction opening (116) disposed in the outer portion (114), and an outer dust sealing ring (117) enclosing the interior space (111), the inner dust sealing ring (112) and the outer dust sealing ring (117) being arranged to define a common working plane parallel to the plane of rotation of the carrier plate (120).

Abstract: A tool for chamfering cleaved tips of optical fibers. The tool including conical bores of relatively smooth and hard material terminate at a cylindrical bore that is slightly larger than the fiber core maximum diameter and a fiber centering bore that is slightly larger than the fiber coating maximum diameter. The tool provided such that when a cleaved fiber tip is inserted into the centering bore the sharp edge falls upon the chamfer that, when rotated relative to the fiber, gently grinds the edge to the chamfer angle. Chamfering cannot occur on the core face due to the absence of tool surface at this dimension.

Abstract: In an angle electric power tool 1 in which an output axis P intersects and is orthogonal to a motor axis J, a battery attachment portion 40 is provided to the rear of a grip 30 so as to extend in the rearward direction and a battery pack 50 is configured to be attached to an upper surface of said battery attachment portion 40. Because of this configuration, the battery pack 50 does not directly come into contact with a working surface W, thereby preventing flaws and scratches on the working surface W.

Abstract: An aircraft assembly having a bush mounted within a lug and a recess which extends along a portion of the lug-bush interface to create a relatively wide cavity for receiving sealant.

Abstract: An electric motor includes a housing shell, an electrical component, and a baffle for directing airflow to the electrical component. The baffle includes a baffle connection element. The shell includes a shell connection element. Interengagement of the connection elements at least substantially restricts axial shifting of the baffle.

Abstract: A method for manufacturing a polishing pad for a hand tool having a working element performing an orbital, random orbital, and/or a rotational movement, the polishing pad having attached layers including: a resilient damping layer, an adhesive layer for connection to a corresponding layer located at a bottom surface of the working element, and a polishing layer including microfiber for polishing a surface of a work piece. The method includes the steps of: providing a casting mold having a recess corresponding to form of the polishing pad and a lid for closing the recess; placing the adhesive layer into the recess; pouring the resilient material for the damping layer into the recess on top of the adhesive layer; placing the polishing layer on the resilient material; closing the recess with the lid; and manufacturing the polishing pad under external heat supply until the resilient material is cured.

Abstract: A dust and debris extraction device for the purpose of capturing dust and debris created by a chisel held by a power tool has an opening for a chisel to pass through at the front and is guided upward by a sleeve that passes out the top of the body of the device. The extraction end of the device has a locking mechanism to keep a hose going to a negative air source attached. The dust and debris extraction device may either free float on the shank of the chisel or be fixed to the power tool with a bracket.

Abstract: A hand-guided machine tool is provided, in particular a hand-guided electric power tool, having a housing, whereon a grip part is provided which projects from a stop surface at one end of the housing, wherein the stop surface protrudes laterally with respect to the grip part at all sides and merges into the grip part via a preferably concave curvature.

Abstract: A system for the polishing treatment of inner walls of aquatic enclosures includes at least one tank of abrasive mixture and at least one surface treatment head which communicates fluidically with the tank of abrasive mixture, a mover allowing the treatment head to be moved along the wall to be treated, and a supply allowing the treatment head to be supplied with a substantially continuous flow of abrasive mixture.

Abstract: A grinding machine includes a grinding machine body and a grinding disc connected to the grinding machine body. The grinding machine body is provided with a pressure cavity at a position facing the grinding disc and a gas intake pipe corresponding to the pressure cavity. A pressure release gap in communication with the pressure cavity is formed between the grinding machine body and the grinding disc. The gas intake pipe induces a high-pressure gas into the pressure cavity, which receives an effect of the high-pressure gas to become a positive-pressure environment. The high-pressure gas is continually released via the pressure release gap to prohibit external dust from entering the pressure cavity. Thus, the grinding machine is capable of preventing dust from accumulating in the pressure cavity as well as effectively preventing moisture from entering the pressure cavity when the grinding machine is applied for wet grinding.

Abstract: A pad for supporting an abrasive disc by being fixed with the abrasive disc to a shaft of a grinder, the pad including a supporting surface opposing the abrasive disc. In a radial direction, an outer edge of the supporting surface is located inward of an outer edge of the abrasive disc. The supporting surface includes a taper portion inclined away from the abrasive disc as it approaches the outer edge of the supporting surface. The abrasive disc is not fixed to the taper portion.

Abstract: A foot attachment for a pneumatic rotary tool is configured to be attached to a nose portion of the housing of the tool. The rotary tool includes a housing that defines an air flow channel. A nose portion of the housing defines an air flow inlet for the air flow channel. The foot attachment includes a shroud portion that extends from the nose portion of the housing and surrounds a working space in front of the nose portion of the housing. The shroud portion defines at least one tangential opening that directs air flow into the shroud portion along a tangent such that a vortex is generated within the working space.

Abstract: Implementations of the present disclosure generally relate to planarization of surfaces on substrates and on layers formed on substrates, including an apparatus for in-situ temperature control during polishing, and methods of using the same. More specifically, implementations of the present disclosure relate to in-situ temperature control with a condensed gas during a chemical-mechanical polishing (CMP) process. In one implementation, the method comprises polishing one or more substrates against a polishing surface in the presence of a polishing fluid during a polishing process to remove a portion of a material formed on the one or more substrates. A temperature of the polishing surface is monitored during the polishing process. Carbon dioxide snow is delivered to the polishing surface in response to the monitored temperature to maintain the temperature of the polishing surface at a target value during the polishing process.

Abstract: An improved handle arrangement is provided for a power tool, such as a sander. The sander may include: a housing; a primary handle extending in a rearward direction away from an upper rear portion of the housing; a secondary handle positioned at an upper front portion of the housing, where the secondary handle is formed as a knob protruding in a forward direction which is opposite the rearward direction; a platen coupled to a lower portion of the housing; and a motor assembly disposed within the housing. A groove may be formed into an exterior surface of the housing along an intermediate portion of the housing, such that the intermediate portion extends between the primary handle and the secondary handle and the groove extends from a top surface of the housing towards a lower portion portion of the housing along opposing side surfaces of the housing.

Abstract: The end face grinding method includes a structure rotating step of rotating a honeycomb structure based on a rotation axis in a direction orthogonal to the end face of the honeycomb structure, a grinding wheel reverse rotating step of using a grinding wheel disposed so that a grinding surface faces the end face and rotating the grinding wheel in a reverse rotating direction to a rotating direction of the honeycomb structure based on a rotation axis in the direction orthogonal to the end face; and a dry type grinding step of bringing the grinding wheel rotating in the reverse direction close to the rotating honeycomb structure to perform the dry type grinding of the end face.

Abstract: An Adaptive Dust Shield Device having Zero Standoff Capability for rotary grinders having a bearing housing and an axial groove around the bearing housing. The dust shield has a cover molded from a single shot. The cover has a plurality of upstanding flexible fingers, in multiples of four, which extend upward from the cover. A door is formed in one side of the dust shield cover to allow the user to use the dust shield in zero clearance situations. The flexible fingers have a defined width and are separated apart from each other by a space between each one. The width of the space is less than the defined width of the flexible fingers. A stretchable fitting ring fits onto the bearing housing of the grinder and under the flexible fingers. The flexible fingers are secured onto the stretchable fitting ring by a securing fastener. There are a plurality of vent holes formed in the top wall that are selectively pluggable with plug elements.

Abstract: The present invention relates to a backing pad (1) with slots for sanding discs with multiple holes, comprising three parts, upper, intermediate and lower, joined together by a fastening system in which the upper part (2), with a frustoconical shape, includes suction holes (7) and a central hole (8), characterized in that the intermediate part (3) comprises intermediate suction slots (5), a central hole (8?) and in the rear face some suction channels (6) bordered by upraised walls (10); and the lower part (4), with a frustoconical shape, and in which the intermediate part (3) will engage, comprises lower suction slots (11) and a central hole (8?), and said lower suction slots (11) are arranged in rings, concentric and equidistant between them, and the size of each of the lower suction slots (11) increases from the center to the periphery.

Abstract: A method for memorializing a sports jersey via creating a shimmering light-reflective pattern resembling a three-dimensional wave on a plurality of two-dimensional metallic surfaces features obtaining a plurality of planar metallic blanks. The method features obtaining an angle grinder having a circular grinding disc located thereon. The method features embedding a first series of arc-shaped striations sequentially located one above another along a first striation axis on each metallic blank via operation of the angle grinder. The method features embedding subsequent series' of arc-shaped striations sequentially located one above another along subsequent striation axes on each metallic blank via operation of the angle grinder. This step is repeated until the desired shimmering light-reflective pattern resembling a three-dimensional wave on a two-dimensional metallic surface is achieved. The method features assembling the metallic blanks, one atop of another creating layers.

Abstract: A guard lock for a powered apparatus having a neck extending from a gear case is provided. The guard lock includes a guard member having a body portion for at least partially surrounding a working member of the power tool and a collar connected to and extending from the body portion, where the collar includes multiple windows that are spaced from one another. The guard lock also includes a stop lever coupled to the gear case via a fastener about which the stop lever may pivot, the stop lever including an engagement portion and a distant arm portion, and a biasing member for biasing the engagement portion of the stop lever toward a window of the collar. When the engagement portion is positioned within a window, rotation of the collar is permitted in a first direction where the window engages a first surface of the engagement portion but is prevented in a second direction where the window engages a second surface of the engagement portion.

Abstract: A method and apparatus for deburring a metallic surface is disclosed. The method and apparatus utilizes a handheld orbital sander that is compact so that machine marks disposed in tight places can be reached. Additionally, a conformable sanding pad is utilized to allow the sanding pad to conform to the unique contours of the metallic surface to eliminate the machining marks.

Abstract: The invention relates to a securing plate (10), a fixing device and to a method for fixing an electric machine (12), for example to a component (30) of a motor vehicle, comprising a central through-opening (14) for receiving a round bearing sleeve (16) of the electric machine (12), said through opening (14) having a polygonal shape (15), the lateral surfaces (18) resting on the bearing sleeve (16). The securing plate (10) has, in a radially outer region (20), securing holes (22) via which the electric machine (12) can be secured to the component (30).

Abstract: Exfoliating heads with an abrasive surface are disclosed for use with a personal care appliance. The personal care appliance is configured to oscillate the exfoliating head to provide improved smoothing and exfoliation of a subject's epidermis with or without the antecedent application of skin care formula. The oscillating action of the exfoliating head may be rotational, translational, or a combination thereof. In use, the personal care appliance oscillates the abrasive surface of the exfoliating head over a subject's skin in order to remove dead skin from the subject's epidermis. The exfoliating heads may be used to treat rough skin conditions, such as calluses or corns, which have developed on a patient's hand or foot.

Abstract: A cutting unit includes a spindle housing, a spindle, a mounter fixed to the front end portion of the spindle for supporting a cutting blade, and a fixing flange for fixing the cutting blade to the mounter. The mounter includes a boss portion for axially slidably supporting the fixing flange, the boss portion being fitted to an engaging hole formed in a central portion of the fixing flange, a flange portion projecting radially outward from the outer circumference of the boss portion, the flange portion having a supporting surface for supporting the cutting blade on the front side opposed to the fixing flange, and a cylindrical portion formed on the rear side of the flange portion. The flange portion has a suction hole opening. The cylindrical portion has a communication passage communicating with the suction hole. The communication passage is connected through a rotary joint to a suction unit.

Abstract: Polishing pad for use with high-speed mechanical buffers or for use by hand. More specifically, a polishing pad and methods of use for the polishing pad, the polishing pad having a foam pad, and having a cloth, a foam, or both attached to a top surface of the foam pad, with the cloth, the foam, or both covering part of the top surface of the foam pad such that gaps in the coverage allow for the foam pad and either the cloth, the foam, or both to touch a polishing surface at the same time.

Abstract: Polishing pad for use with high-speed mechanical buffers or for use by hand. More specifically, a sloped polishing pad and methods of use for the polishing pad, the sloped polishing pad having a sloped foam pad, and having a cloth, a foam, or both attached to a top surface of the foam pad, with the cloth, the foam, or both covering part of the top surface of the sloped foam pad such that gaps in the coverage allow for the sloped foam pad and either the cloth, the foam, or both to touch a polishing surface at the same time.

Abstract: A medical manipulator is provided. The medical manipulator includes an end effector that is configured to perform motions with respect to at least two different axes, and that is inserted in a body cavity during operation of the medical manipulator. The medical manipulator also includes at least two cylindrical motors that each include a longitudinal axis and that drive at least a part of the end effector. The motors remain outside a living body during operation of the medical manipulator and the motors are mounted on at least one bracket. A shaft interconnects the bracket and the end effector. A longitudinal axis of the shaft extends substantially parallel to each of the longitudinal axes of the motors.

Abstract: An electric hand power-tool appliance is described and which includes a spindle, a tool mounted on the spindle, a supporting element mounted on the spindle and which is movable along the spindle on a path L, and against a force F, and in the direction of the electric hand power-tool appliance, and which increases the safety of the electric hand power-tool appliance.

Abstract: A portable power tool includes a motor located in a motor housing of the tool and having a rotary output shaft, a working part arranged to be driven by the rotary output shaft, a dust collection container arranged to collect dust produced by the operation of the power tool on a workpiece during use, and a fan. The fan is arranged to be rotated about an axis by the motor to convey the dust to the dust collection container, the axis of rotation of the fan being non-coaxial with the rotary output shaft of the motor. A part of an exterior surface of the dust collection container is formed as a recess into which the motor housing at least partly extends, such that the dust collection container extends at least partly around the motor housing.

Abstract: A handheld abrading machine is provided, including a holding device which includes a substantially tubular bar having a proximal end and a distal end and having a drive motor arranged at the proximal end and a tool head arranged at the distal end, and a transmission shaft connecting the drive motor to a tool holder of the tool head and running within at least sections of the tubular bar. The tool head includes a hood device which includes a hood element having a substantially cylindrical hood chamber, wherein the tool holder together with a tool arranged thereon is arrangeable in at least sections of the hood chamber. The hood element includes a recess in the form of a segment of a cylinder so that a tangent touching an edge of the tool runs substantially in a plane delimiting the recess in the form of a segment of a cylinder.

Abstract: A backing plate unit for a rotary grinding machine includes a backing plate with a front face for mounting a grinding disc and a back face opposite the front face, a drive shaft that can be attached to the tool adaptor of the rotary grinding machine, and a suction hood that is rotatably fixed to the drive shaft. The backing plate 10 includes suction openings that penetrate the backing plate so that the suction hood 30 vacuums dust through the backing plate to the back face of the backing plate.

Abstract: A pad conditioner for a CMP polishing pad is disclosed that includes a substrate that has a matrixical arrangement of protrusions that have a layer of poly crystalline diamond on at least their top surfaces. The protrusions may have varying shapes and elevations and may comprise a first set of protrusions and a second set of protrusions, the first set of protrusions have a first average height and the second set of protrusions have a second average height, the first average height different from the second average height, a top of each protrusion in the first set of protrusions has a non-flat surface and a top of each protrusion in the second set of protrusions has a non-flat surface.

Abstract: The present invention is directed toward a shield assembly for a handheld tool device such as an angle grinder. The shield assembly is selectively repositionable with respect to the cutting tool. A lock mechanism secures the shield assembly in discrete rotational positions relative to the cutting tool. The shield assembly includes a guard member and a bumper member, and an alignment feature configured to align the relative positions of guard member and the bumper member, thereby positing the members in a predetermined relative orientation. With this configuration, the shield assembly is selectively repositionable via a “hands-free” mechanism that permits a user to adjust the position of the shield assembly by simply contacting the shield assembly against a work surface.

Abstract: A motor driven angle grinder is described and which includes an electric motor; a transmission coupled to the electric motor and which includes a motor shaft and a tool spindle; a crown wheel in the form of a hat is provided and which forms a recess that receives the tool spindle and a bearing, and wherein the crown wheel defines toothing which surrounds the recess, and wherein the transmission housing and the angle grinder have low relative height profiles which permits the angle grinder to be used in restricted or tight space working environments.

Abstract: A turbine servicing device includes a base member mountable proximate an inlet of a section of a turbine system. Also included is a retaining component operatively coupled to the base member. Further included is a rod having a first end and a second end, the rod in a slidable and pivotable relationship with the retaining component. Yet further included is a machining device operatively coupled to the rod proximate the second end and configured to polish a portion of a turbine component.

Abstract: An arrangement includes a grinding wheel and a hand-held power tool. The hand-held power tool comprises a housing, a drive shaft, a drive unit configured to drive the drive shaft, a first handle and a second handle which are each fixed on the housing, a sensor, and an evaluation and control device. The sensor is configured to record at least one property information of the grinding wheel so as to determine a diameter of the grinding wheel. The evaluation and control device is configured to generate a setpoint value for a rotational speed based on the at least one property information of the grinding wheel recorded.

Abstract: A run-off securing device, in particular a run-off securing device of a handheld power tool, is configured to avoid running off of a clamping element and/or a tool from a spindle. The device has at least one transmission unit, which is removably coupled to the spindle and has at least one first transmission element and at least one second transmission element. The at least one second transmission element is movable in relation to the at least one first transmission element. The transmission unit has at least one movement changing unit, which at least partially transforms a first relative movement between the at least one first transmission element and the at least one second transmission element into a second relative movement in a braking mode.

Abstract: A holding body includes a fastening layer which has a fastening surface configured to fasten a flexible grinding device. The fastening layer includes an air- and dust-permeable material and is substantially full-surface. The fastening layer includes a textile material. The holding body also includes a supporting body which has a supporting surface configured to support a holding surface of the fastening layer. The supporting body is air- and dust-permeable and includes an open-cell foam. A grinding system includes such a holding body and such a flexible grinding device.

Abstract: A handheld grinder comprising a housing; a grinding disk; a motor; an output shaft connected to the grinding disk and the motor to impart rotary motion thereto; and a circuit board residing in the housing and having thereon a rectifier that receives an alternating current and converts the alternating current to a direct current, a switching arrangement having a plurality of motor switches connected electrically between the rectifier and the motor and operates to deliver the direct current from the rectifier to the motor, a capacitor connected electrically between the rectifier and the switching arrangement, wherein the capacitor is coupled in parallel across the rectifier, a driver circuit interfaced with the motor switches and operable to control switching operation of the motor switches, and a power switch connected electrically between the rectifier and the driver circuit and operable to selectively energize the driver circuit and power on the grinder disk.

Abstract: A supply device for a handheld power tool for a cutting grinder includes a cutting tool and a protective cover which at least partially surrounds the cutting tool. The supply device includes a U-shaped element which can be arranged on the protective cover and via which a fluid medium can be supplied to the cutting tool. The U-shaped element has a connection piece on which a coupling element can be arranged. On the coupling element a pipeline can be connected via which the fluid medium can be supplied to the U-shaped element through the connection piece. The coupling element can be turned about the axis of rotation of the connection pieces.

Abstract: A portable apparatus (1) for the tooling of a workpiece (9) comprises a motor (3) with a cyclic movement output member (4), a tool holder (5) adapted to carry a tool (6) and a movement transmitter (7) engaging the motor output member (4) and the tool holder (5) to set the tool holder (5) in a cyclic movement, wherein the movement transmitter (7) comprises a transmission ratio adjuster (8) that, in response to a preset reduction of the cyclic movement speed (?_m) of the output member (4) of the motor, increases the transmission ratio (?_m/?_ph) thereby reducing the cyclic movement speed (? ph) of the tool holder (5) with respect to the cyclic movement speed (?_m) of the output member (4) of the motor (3).

Abstract: A machine tool braking device, particularly a hand-held machine tool braking device, includes at least one braking unit and at least one control unit. The control unit includes a moveably-mounted control element that is configured to activate and/or deactivate the braking unit. The control element has a movement axis and is mounted such that the control element can pivot about the movement axis.

Abstract: The present invention is an original direct motor-drive portable angle grinder with a disc type motor installed in a position adjacent to the grinding wheel and an outer motor rotating part coaxially and directly driving the grinding wheel. By means of the direct drive, the present invention prevents the emission of noise made by angle type transmission devices. Moreover, an inertial body is installed on the rotating housing that is integrated with the rotating part to form a flywheel or the rotating housing and the inertial body are integrated into a single reinforced structure to enable a flywheel function in order to improve the grinding, polishing and machining or cutting abilities of the grinding wheel.

Abstract: The invention discloses a self-leveling sandpaper grinding machine, comprising a base part including a seat, a motor frame fixed to the seat, a motor supported on the motor frame, a decelerator connected to an output shaft of the motor, in which an output shaft of the decelerator penetrates the seat and extends to the other side of the seat; and a grinder part attached to the seat and opposing to the motor, which includes a tray, four barrier strips provided on the tray and forming a quadrangle, U-shaped clip seats provided along diagonals of the quadrangle, elastic pads inserted into sockets formed by the barrier strips and clip seats, sandpaper placed on the elastic pads, U-shaped clips for engaging with the clip seats and fastening the sandpaper together with the clip seats, and a transmission mechanism provided on the tray and for coupling with the output shaft of decelerator.

Abstract: In one illustrative embodiment, a grinder may comprise an arbor configured to rotate about a first axis and to support a grinding wheel for rotation therewith, a gear surrounding a first portion of the arbor and having a slip fit with the first portion of arbor, a motor configured to drive rotation of a drive train including the gear, a collar surrounding a second portion of the arbor and having an interference fit with the second portion of the arbor such that the collar is constrained for rotation with the arbor about the first axis, and at least one spring disposed between the gear and the collar and configured to exert a biasing force along the first axis such that one or more resulting friction forces cause the arbor to rotate with the gear when a torque exerted on the gear is less than a threshold torque.

Abstract: A sander capable of correcting airflow amount comprises a body and a correction valve. The body includes an air intake passage to receive pressurized air, a drive motor driven by the pressurized air to rotate at a rotational speed including a preset range and an excessive range, and a regulation valve located on the air intake passage to adjust the rotational speed of the drive motor in the preset range. The correction valve includes an adjustment portion operable in an adjustment displacement and a mask wall movable by the adjustment portion to block the air intake passage. The adjustment portion determines the flow amount of the pressurized air passing through the correction valve according to the adjustment displacement thereof to confine the rotational speed of the drive motor from the excessive range to the preset range, thereby controls the rotational speed of the drive motor in the preset range.

Abstract: A grinding device is specified, comprising a housing in which a tool spindle for driving a tool is mounted, comprising a protective hood which can be locked on the housing, and comprising means which allow the tool spindle and the protective hood to be locked. An actuating device is provided which is displaceable on the housing between a first position in which the tool spindle is released and the protective hood is locked against rotation and a second position in which the tool spindle is locked against rotation and the protective hood can be adjusted in the angular position thereof on the housing.