Abstract: The invention relates to a device (1) at a mobile grinding machine (2) for stone materials and that comprises a rotatably driven disc-shaped housing (3), which is arranged to support a plurality of grinding disc holders (6) rotatably driven by a belt (5) or chain driven by a motor (4), which holders are distributed along the circumference of said housing (3) and supported by shafts (11) connected to said housing (3) at a mutual distance from each other. According to the invention, internally (7) in a casing (8), which surrounds a said housing (3), a gear rim (10), situated concentrically with a centre driving shaft (9), is arranged non-turnably connected to the casing (8). The grinding disc holder shafts (11) support an intermediate coupling cogwheel (18) each that co-operates non-turnably with the appurtenant shaft and with said gear rim.

Abstract: The present invention generally relates to a polishing system. Particularly, the present invention relates a polishing apparatus having one or more modular polishing stations, and a plurality of polishing heads movably connected to a transferring system.

Abstract: An apparatus for a stand-up grinder caddy includes a handle assembly and an upper sheath. A lower caddy includes a wheel assembly and a lower sheath for insertion into the upper sheath. A bracket supports a grinder with the bracket attached to a support frame with a joint and to sides of the support frame with a floating head mechanism arranged so as not to extend above a top of the frame and thus minimize a height of the lower caddy for fitting under low overhanging obstacles. A head of the grinder contacts the floor surface and can follow contours of the floor surface. When a tilt handle is pressed the head can be tilted. A height adjustment mechanism adjusts a vertical position of the handle assembly for different user heights. The handle assembly can be rotated to a position such that the lower caddy can pass under overhanging obstacles.

Abstract: The invention relates to a mobile floor-cleaning machine having a rotationally drivable, disk-like cleaning tool which is detachably held on a tool holder, the tool holder being connected to a drive shaft in a rotationally fixed manner. In order to develop the floor-cleaning machine in such a way that the cleaning tool can be easily replaced, the invention proposes that said cleaning tool is adapted to be detachably latched to the tool holder and to be disconnected from the tool holder in the axial direction by means of an unlatching mechanism which is adapted to be operated by the user.

Abstract: An improved mechanism for grinding surfaces flat is presented, involving a precision grinder with grinding heads that are adjustable in a vertical dimension controlled by a support structure on wheels. The support structure has an adjustable wheelbase that allows sinusoidal flaws in a surface to be ground down in a controllable way. The device can be used in coordination with floor flatness measurement devices to grind concrete floors, and other horizontal surfaces.

Abstract: A method is disclosed for treating or maintaining a hard surface comprising a stone or stone-like material, the method comprising treatment of the surface with a flexible pad, in the presence of abrasive particles, bonded to the pad, on a contact surface between the pad and the hard surface, wherein the abrasive particles comprise diamond particles, and the treatment is performed in the absence of an effective amount of crystallization agent on the contact surface. The treatment is performed on a substantially regular basis, such as daily, weekly or monthly, and the treatment is performed using a pad comprising an open, lofty, three dimensional non-woven webs of fibers. A tool for use in the method is also provided, as well as a floor-surfacing machine comprising such a tool and a method for manufacturing such a tool. Furthermore, methods for treating or maintaining hard, smooth surfaces such as wood, polymer material, lacquer, linoleum, gelcoat, glass and automotive enamel are disclosed.

Abstract: The disclosure relates to the floor scrubbing or finishing machines. There is provided a machine for scrubbing or finishing a floor surface comprising carriage means adapted for translational movement over a floor surface, a workhead, an electric motor carried by the carriage means and arranged in use to drive the workhead and battery support means adapted in use to support at least one battery as a source of electric power for driving the electric motor, wherein said battery support means are adapted to support said at least one battery so that said at least one battery can be positioned in a selected one of a range of positions relative to said workhead whereby the loading on said workhead can be varied as required.

Abstract: A planetary grinding machine having a simple design with a minimal number of parts, which are all easily accessible for maintenance and repair is disclosed. The machine has a rotating planetary disk with rotating screeding disks attached. The planetary disk is driven by a shaft extending through a top housing cover plate, which supports a transmission driven by a motor. As the planetary disk rotates, a single belt engages a stationary gear on the cover plate and pulleys on screeding disk shafts to turn the screeding disks as the planetary disk is turned. The belts and pulleys for the drive mechanism are sandwiched between the planetary disk and the top cover to protect the mechanisms from dust and debris. The bearings are sealed to prevent dust and debris from entering and oil from escaping. The bearings, being on the inside of the planetary disk, keep oil from landing on the floor.

Abstract: A method and apparatus for finishing cured concrete floors using a riding trowel to which large diameter pans are attached having a balanced distribution of abraders releasably secured to the undersides of the pans. The individual abraders are preferably individually spring biased so as to maintain full contact with the floor when traversing undulations of the floor.

Abstract: A rotary floor sanding machine has a vertically oriented bell housing with a backside floor support and a dust suction port for removing dust from within. The bell housing encloses the sides and backside of a disk casing and rotary sanding pad. The floor support is configured to place the floor contact area of the sanding pad forward of center. There is a lifting vane extending from proximate the floor contact area of the sanding pad in the direction of rotation towards the suction port in the bell housing to elevate dust particles to the higher velocity airflow near the suction port. There may be a shield for reducing the floor level opening between the back edge of the disk casing and the bell housing.

Abstract: An abrasive disk assembly is provided for a floor resurfacing machine wherein the floor machine has at least one shaft configured to rotate about an axis substantially orthogonal to a work surface, the abrasive disk assembly including a head assembly of predetermined dimension configured to be coupled to one end of the shaft of the floor machine proximate the work surface, the head assembly including a central portion to be coupled to the shaft and a carrier portion for receiving at least one abrasive pad thereon, the carrier portion including at least one coupler in the form of a hook, a tab, a finger, a flange, and a tab extending from a peripheral edge of the carrier portion. At least one abrasive pad assembly is detachably coupled to one of the central portion and the carrier portion, and includes a first end received over the coupler and an opposite end to be attached to one of the central portion and the carrier portion.

Abstract: The present invention provides an assembly of machined or precision cast components which combine to form a high pressure water powered motor. The motor includes a rigid metal housing, a high pressure water inlet, an impeller rotatably mounted within the housing, an output drive shaft for connection to a machine tool and at least one handgrip or alternatively an extendable handle capable of articulation throughout an extended range. The motor is attachable to a pump driven by an electric motor or internal combustion engine to provide high pressure water thereto.

Abstract: The invention relates to an arrangement in a mobile machine for screeding floor surfaces. This comprises a housing with a planet disk (3), which is rotatably supported in the bottom of the said housing and driven by a drive motor (1). The planet disk carries a number of rotatably supported screeding disks, distributed over the planet disk (3) and operatively connected to the drive motor (1). According to the invention the number of screeding disks is an even number up to a maximum of six. Viewed in the direction of rotation of the planet disk (3), half the number of screeding disks have a direction of rotation coinciding with the planet disk (3) and the remaining screeding disks an opposing direction of rotation.

Abstract: An apparatus for abrading a surface is provided. The apparatus has a compact profile and includes a drive mechanism disposed in a housing. The drive mechanism includes a substantially vertical drive shaft rotatably mounted on a first plate and including a drive pulley mounted on the shaft. The drive pulley is rotatably connected to at least one coplanar pulley mounted on a substantially vertical shaft and disposed between the first plate and a second plate attached substantially parallel to the first plate. Thus, use of the apparatus in height-restricted spaces is facilitated.

Abstract: A floor care machine such as a floor polisher includes a machine frame carrying a motor coupled through a drive arrangement to a rotationally driven head on which a floor care disc such as a polishing pad is mounted. The drive arrangement includes a drive element rotationally driven by the motor, and a driven element that is connected to the driven head and is automatically height adjustable. The drive element includes a bearing hub, an outer ring and four uniformly rotationally offset spokes that carry first rolling guides extending along helical paths about the rotation axis. The driven element includes upper and lower partial elements that receive the spokes therebetween and carry second rolling guides arranged facing the first rolling guides along the helical paths, and roller bodies are interposed therebetween. Relative rotation between the drive element and the driven element causes an axial height adjustment of the driven head.

Abstract: A clamping fixture for detachably fastening a disk-shaped tool on a rotatably driven working spindle with a driven gear includes a fastening element a supporting flange arranged so that the tool is accommodated between the fastening element and the supporting flange and rotatably displaceable relative to the working spindle in the tightening direction and axially in a direction toward the tool. The supporting flange is displaceable relative to the working spindle in a release direction and axially away from the tool when the fastening element is released, and is lockable with the working spindle or a component which is non-rotatably connected with the working spindle in a position which is displaced axially in a direction of the tool, and the supporting flange cannot be displaced axially away from the tool until a lock is released.

Abstract: In order to provide a hand-held cleaning/polishing machine, comprising a holding device for holding the cleaning/polishing machine, a drive motor, a tool head for one or more cleaning tools and/or polishing tools, which has a tool drive shaft driven by the drive motor, and a transmission device for transmitting torque from the drive motor to the tool drive shaft, which is universally usable, it is provided that at least one coupling for connecting at least one first fluid line is arranged on the holding device and that at least one second fluid line leads to the tool head from the at least one coupling.

Abstract: A planetary drive head for treating floors having a hub that rotates in one direction and attached media gears that rotate in the opposite direction.

Abstract: The elastic drive belt system connects the belt directly to a drive shaft and driven pulley. The elastic drive belt has a plurality of longitudinal ribs on the traction side of the belt. The drive shaft has a plurality of grooves sized and arranged to receive and engage the longitudinal ribs on the belt to facility torque transfer and alignment. This system facilitates delivery of relatively high amounts of torque to the driven pulley using relatively low horsepower motors. In many applications, such as a sander, the elastic drive belt system eliminates the need to readjust the tension on the belt as it wears.

Abstract: An abrasive abrading a grinding device (10) having a housing (12) for moving over a concrete surface. The housing has depending abrasion elements (14) with a substrate layer (30) and a backing layer (32) mounted to a support bracket (34) that in turn is affixed to the housing. The substrate layer (30) has a front surface (44) with a distal section (40) having abrasive particles (42) brazed thereon with brazing material (46).

Abstract: A riding floor sander for large hardwood floor surfaces, such as gymnasiums and dance floors, has a powered cart with one or more sanding machines connected to it. A blower picks up the process waste in a stream of air and and moves it to a cyclone separator that is mounted on the riding sanding machine. There the dust is separated from the air stream, leaving clean air to be returned to the ambient. The dust that falls from the cyclone into a dust collection drum or bag on the cart. There can be are primary cyclonic separators on the sanding machines, and a cyclonic separator on the back of the riding cart. Alternatively, the cyclone and drum may be located remote from the riding sander, and can have an in-line auxiliary pump or impeller.

Abstract: A cleaning element (36) for a cement floor surface mounted to a housing (32). Each cleaning element has a flat flexible abrasive surface (39) that is transversely positioned to the direction of motion to provide flex during cleaning of a cement floor surface.

Abstract: A floor sanding machine is proposed, which consists of a case body (11) and a plurality of sanding tools (30) arranged eccentrically in the case body (11). The axes of the tool shafts (31) rotate about the axis of a central shaft (12), and the sanding tools (30) rotate about the axis of the tool shaft. The construction consists essentially of a belt drive, of which the unilaterally grooved drive belt (3) is driven on the grooved side of the main drive pulley (2) and drives a gear mechanism (5). Also on the grooved side of the drive belt (3), a belt tensioner (6) ensures that the drive belt (3) is always under sufficient tension. The tools (4) are driven via the non-grooved side of the drive belt (3).

Abstract: The present invention concerns a grinding apparatus (1) including a number of grinding units (3), a number of drive units (11) and a number of screen units (2), where a number of the grinding units (3) are enclosed by at least one of the screen units (2), and where at least one the screen units (2) is arranged with a pipe connection (4) adapted for connecting one or more suction units (21), where the screen unit (2) with the pipe connection (4) is designed along a lower edge (6) with a number of spacer members (7) that are arranged adjustable and replaceable, and a number of sealing members (8) that fit tightly to an underlying surface, that the spacer members (7) establish an adjustment of spacing of the grinding units (3) relatively to an underlying surface, and that the sealing members (8) interact with the suction units (21) for forming a vacuum that holds the grinding apparatus (1) against the said surface during operation.

Abstract: A floor treating machine has a frame and a housing connected rotatably to the frame according to a main rotation axis. At least three heads are suspended rotatably with respect to the housing according to respective rotating axes, which are generally parallel to the main rotation axis, as well as a number of drive motors which is at least equal to the number of heads. Each head is connected to its own respective drive motor.

Abstract: The invention concerns a carrier plate (2) holding an abrading element, for detachable mounting on a rotatably mounted abrading plate (1) driven during use, for abrading stone or concrete floors, which carrier plate (2) has sides (2a, 2b) which form an acute angle with each other. The sides (2a, 2b) have flanges (2a1, 2b1) which are formed for surrounding engagement with a shoulder (1a) arranged on the abrading plate (1) so that the carrier plate (2) can be fixed on the abrading plate (1) with an engagement based on form and friction.

Abstract: The present invention provides an assembly of machined or precision cast components which combine to form a high pressure water powered rotary tool. The rotary tool includes a rigid metal housing, a high pressure water inlet, an impeller rotatably mounted within the housing, an output drive shaft, a backing disk and at least one handgrip or alternatively an extendable handle capable of articulation throughout an extended range. The rotary tool is attachable to a pump driven by an electric motor or internal combustion engine.

Abstract: The invention is a riding floor polishing and grinding machine that uses one or more gangs of polishing heads (242) to treat concrete and similar surface flooring (208). A compact vehicle (210) equipped with a front loader arm (235) is fitted with a module (240) containing the gang(s) of polishing head. The vehicle (210) is capable of raising and rotating the module to easily change the pads attached to the polishing heads. Each polishing head is individually powered by a motor and floats over the floor surface. The pads attached to the polishing heads can be of many different types, preferably diamond-impregnated polishing pads. The invention enables operator to more quickly and efficiently remove material from a floor surface. The design also enables gangs of pads to be mounted with different grit ratings to perform different treatment operations using a single machine in a single pass over a floor surface.

Abstract: Apparatus for treating flooring surfaces, the apparatus includes a drum assembly which provides counter-rotation of the drum assembly relative to the direction of rotation of the surfacing discs to provide improved handling characteristics. The apparatus also includes a frame with leg structures that pivot relative to the frame and of adjustable height to facilitate maintenance tasks, such as replacement of surfacing disks. A handle structure is also included that can be configured in a variety of positions and adapted to assist with maintenance tasks such as motor removal.

Abstract: Sanding and screening are steps in floor finishing that produce large quantities of fine dust which is difficult to remove and which plugs porous filter elements of dust collection systems. Dust collection is enhanced with a floor screening attachment for a floor machine. A vacuum system with a liquid filtering medium is provided to collect dust produced during screening. A dust collection unit is also disclosed to collect and separate sawdust produced by sanding which can cause foaming of a liquid filter medium.

Abstract: A wheel scraper for a floor sander attaches to the swivel support wheel of a floor sander and scraper debris from the support wheel in order to prevent debris accumulation on the support wheel. The device includes a frame that attaches to the floor sander and that positions a scraper arm that contacts the rolling surface of the support wheel. A spring biases the scraper arm against the support wheel. The scraper arm has a generally U-shaped opening that receives the support wheel and that also scrapes debris from the side walls of the support wheel.

Abstract: A power sanding machine (10) has three circumferentially spaced cogged belts (40) to drive three discs (52) rotatably mounted to an inner bowl (30) which is rotatably mounted to a housing (12), which in turn is connected to an operating handle (14). Mechanical lock can rotationally affix the inner bowl (30) to the housing to circumferentially position a pulley at the left or right edge (326, 322) of the sanding machine or at the front end (330) of the sanding machine. Power cleaning and sanding machines (412, 500, 600) incorporate the three disc (52) arrangement or a direct-drive one disc arrangement (572, 672). The machines (412, 500, 600) include multiple floor finishing units (420, 514, 614) ganged together in unique arrangements.

Abstract: A combined floor edger and grinder having a grinding disk which can be adjusted from engaging the floor while flat to engaging the floor along a front, back or side edge of the disk, depending on the height adjustment of the wheels on either side of the frame. The wheels, shroud and handle can also be adjustable relative to the frame for moving the frame straight back and forth or at an angle such that with the disk adjusted to engage the floor on one side of the frame the wheels and handle can be adjusted such that they are angled with respect to a wall for use as an edger whereby a user can push the device along the edge of a wall in a straight line while edging. The shroud and disk sizes may be easily changed for different jobs. The shroud can be open or close ended.

Abstract: A floor treating machine includes a frame provided with a housing which is supported with respect to the frame in such a manner that it can rotate about a substantially vertical housing axis, at least three heads positioned at intervals around the axis and rotatably mounted to the housing, the axis of each head being about parallel to the housing axis, and each head having a bottom surface provided with treating elements and/or coupling elements for treating members to be coupled to, and a motor on the frame which is in driving interaction with the housing and the heads via respective transmissions. At least two of the heads are drivable by separate respective head transmissions each comprising a head pulley connected to the respective head, a drive pulley interacting with the motor as well as a belt between each pair of a head pulley and a drive pulley.

Abstract: An improved walk behind polisher and grinder is disclosed. The improved walk behind polisher and grinder provides a surface polishing machine capable of operation with increased directional stability and reduced dust accumulation to the essential internal components of the machine. The improved walk behind polisher and grinder includes a drive motor mounted on a frame. The drive motor rotates a central shaft, and the central shaft supports a belt pulley and a rotary housing. The belt pulley mechanically communicates with at least one pinion shaft through an endless drive. Each pinion shaft is mechanically engaged by an internal gear such that rotation of the central shaft causes the pinion shaft to rotate about their own axes in a given direction and to revolve around the central shaft in the opposite direction.

Abstract: The invention relates to a device in a circular disk-shaped cleaning element intended for cleaning by means of a cleaning machine. The element is designed with a number of recesses (3) distributed over the active cleaning surface (2a) thereof Grinding elements (4) containing industrial diamonds and conventionally used for grinding stone and concrete floors are arranged in the said recesses. The grinding elements are fixed in such a way that in use they only come into light contact with the surface that is to be cleaned. The invention further relates to the use of a cleaning element in connection with wet cleaning conventionally performed with a cleaning machine. Alternatively the device may be used in such a way that dry polishing is first performed using the cleaning element, following which wet cleaning is carried out using a conventional cleaning element.

Abstract: A method for cutting a chamfer on an edge of a concrete slab, comprising the steps of: providing a generally circular, rotatable concrete saw blade that is coupled to a right-angle grinder motor with a blade-mounting hub having no blade attachment hardware projecting below a lower major surface of the blade; making an initial planar cut at a desired angle beginning a distance from the edge, thereby creating an initial cantilevered ledge above the initial cut; if the initial cantilevered ledge is not severed from the slab by a cutting action of the blade before the hub is proximate an edge of the initial cantilevered ledge, then fracturing and removing the initial cantilevered ledge from the slab; and making at least one subsequent planar cut continuous with the initial cut and any necessary fracturings and removals of subsequent cantilevered ledges until the chamfer is complete.

Abstract: The invention relates to an arrangement in a mobile machine for screeding floor surfaces. This comprises a housing with a planet disk (3), which is rotatably supported in the bottom of the said housing and driven by a drive motor (1). The planet disk carries a number of rotatably supported screeding disks, distributed over the planet disk (3) and operatively connected to the drive motor (1). According to the invention the number of screeding disks is an even number up to a maximum of six. Viewed in the direction of rotation of the planet disk (3), half the number of screeding disks have a direction of rotation coinciding with the planet disk (3) and the remaining screeding disks an opposing direction of rotation.

Abstract: The head assembly of a floor burnisher is suspended by a main lift assembly and a fine adjustment assembly. The main lift moves the head assembly between a raised position in which the pad assembly is raised and tilted for access, and a lowered position in which the pad driver is suspended slightly above the floor, ready for use. The fine adjustment assembly permits the operator to control very accurately and conveniently the final operating pressure of the pad when the burnisher is turned on.

Abstract: A pneumatic buffing machine including a housing having an internal chamber in which a pneumatically driven motor set is mounted. The motor set includes an eccentric block for driving a grinding disc. A skirt shade is screwed under a bottom of the housing by means of outer thread and inner thread. The skirt shade has a large diameter section and a small diameter section. The skirt shade is formed with a central through hole. The eccentric block of the motor set is passed through the through hole and accommodated in the large diameter section. A shoulder section is formed between the large diameter section and the small diameter section and adjacent to the outer thread of the small diameter section. A top end of the small diameter section serves as a stopper section.

Abstract: A milling disk for a floor machining appliance has a plurality of mounts for holding interchangeable plate-like milling tips, the milling disk being driven for rotation by the floor machining appliance and being held substantially parallel to the substructure to be machined so that the milling tips may bite into the substructure and remove matter from the surface thereof. The milling tips are constituted by ceramic cutting tips.

Abstract: An abrasive sandpaper system having a backing plate (16) with a canted outer periphery (28) and an off-centered aperture (26) for interlocking with lugs (18) of a power driver (12). The sandpaper (30) has a canted outer periphery (38) for riding over raised edges (45) of an uneven wood deck. The backing plate may have a pocket (50) with a side wall (60) to receive the substrate layer (58) of sandpaper (54).

Abstract: Disclosed is a surface finishing pad (59) having a dust extraction aperture (60). The pad may have multiple finishing areas (63) or a number of pads may be mounted to a mounting plate (48, 62) that is driven by orbital drive means. The dust extraction apertures align (60) with vacuum ports through which dust may be carried away from a surface undergoing finishing. The mounting plate (48) may have a plurality of channels (46) to direct dust to vacuum ports for extraction. The pad and the machine disclosed, which uses the pads, allows large areas to be finished without dust clogging the pads.

Abstract: A resurfacing disk which mounts to a rotatable disk mount of a conventional rotary floor resurfacing machine. The resurfacing disk includes a rigid upper disk with four counterbored holes through an upper surface corresponding to four downwardly open holes of each disk mount. A resilient, flanged grommet is retained extending through corresponding holes of a retaining plate mounted to the upper surface. The grommets include respective vertically oriented longitudinal bores closely receive a mounting pin which extends from a corresponding hole of the disk mount. A plurality of rotary cutters each include a bracket which mounts to the upper disk opposite the grommets and an externally toothed cutter rotatably mounted thereto. The rotatable toothed cutters are oriented radially outwardly of the resurfacing disk so as to rotate while engaging the floor as the resurfacing disk spins with the disk mount.

Abstract: A device for the machining of surfaces comprises a first housing unit (1), at which the device is to be supported, and a second housing unit (2), in which at least one tool holding fixture (9) for the grinding tool respectively polishing tool is rotatable mounted. The first and the second housing unit (1, 2) are joined with one another relatively rotatable to each other. Furthermore the device comprises a driving unit to drive the at least one tool holding fixture (9) and to drive the second housing unit (2) for rotation relative to the first housing unit (1). As a result of the superposition of the rotation of the individual tool holding fixtures with the rotation of the housing units, in which the tool holding fixtures are mounted, arise a better and faster machining result, a good superposition of the grinding marks and thus a symmetrical grinding pattern.

Abstract: An apparatus for cutting a chamfer on an upper edge of a concrete slab includes a hub designed for installation on the threaded output spindle of an angle grinder, and a specially-modified diamond-grit-edged rotary blade which mounts on the hub. For a preferred embodiment of the hub, an attachment collar is unitary and concentric with both a blade mounting flange having countersunk attachment screw holes and a blade centering shoulder on the flange. The attachment collar has at least one pair of flattened parallel sides for receiving a wrench used to tighten the hub on the output spindle. The blade, which is equipped with both countersunk attachment holes and a central positioning aperture sized to fit closely over the blade centering shoulder, is attachable with countersinking screws to the mounting flange so that the head of each screw is flush with the surface of the blade.

Abstract: A riding trailer apparatus useful for controlling a floor treatment implement is provided including a frame, an operator support platform, and a hook-up mechanism structured to enable the apparatus to be operably coupled to one of various, conventional floor treatment implements. The apparatus also includes a drive assembly including a bi-directional DC motor and gear assembly, and an having an electronic controller with a speed board coupled thereto.

Abstract: An orbital abrading or polishing tool is provided that includes a tool body to be held and manipulated by a user. A motor is carried by the tool body and has a motor shaft driven for rotation about a primary axis. The motor shaft has a cylindrical portion at one end. A spindle is received within the cylindrical portion of the motor shaft for rotation about a secondary axis offset from and parallel to the primary axis. The cylindrical portion of the motor shaft has an opening extending inwardly to the spindle and a locking element is extendable through the motor shaft opening to engage the spindle in a locking relationship.

Abstract: A burnishing machine having a burnishing motor in a motor compartment covered with a hood defining an air plenum having at least one air inlet positioned near the top of the hood spaced from the floor. The plenum includes a discharge outlet immediately adjacent the motor such that clean air is drawn through the air inlet, flows through the plenum to the discharge outlet for providing clean air to cool the burnishing motor.

Abstract: A pneumatic sanding machine includes a body, a pneumatic motor assembly mounted in the body and a control valve detachably mounted in the body to change the path of compressed air that actuates the sanding machine. The control valve includes a first portion selectively closing one of different air passages in the body at a time, a second portion and a neck portion interconnecting the first portion with the second portion. Thus, a dust bag or a vacuum cleaner can be connected to the sanding machine to collect dust or sanding debris so that the sanding machine provides three different ways of dust collection, one of which is not to deal with the powder, the second is to collect the powder into a dust bag, and the third is to vacuum the powder into a vacuum cleaner.