The invention relates to a device (100) for machining a surface of a workpiece (200a). According to one embodiment, the device (100) comprises a frame (160) and a roller carrier (401), on which a first roller (101) is rotatably supported and which is supported on the frame (160) in such a way that the roller carrier can be moved in a first direction (x). The device (100) comprises at least a second roller (103), which is supported on the frame (160), and a belt (102), which is guided at least around the two rollers (101, 103) and because of the tension of which a resulting belt force (102) acts on the roller carrier (401). The device (100) also comprises an actuator (302), which is mechanically coupled to the frame (160) and the roller carrier (401) in such a way that an adjustable actuator force (FA) acts between the frame (160) and the first roller (101) in the first direction (x). The belt (102) is guided by means of the second roller (103), or by means of the second roller (103) and further rollers (101a, 101b, 121a, 121b, 105), in such a way that the resulting belt force (FB, FB) acting on the roller carrier (401) acts approximately in a second direction (y) orthogonal to the first direction (x) in the case of a target deflection of the actuator (302).

The invention relates to a device (100) for machining a surface of a workpiece (200a). According to one embodiment, the device (100) comprises a frame (160) and a roller carrier (401), on which a first roller (101) is rotatably supported and which is supported on the frame (160) in such a way that the roller carrier can be moved in a first direction (x). The device (100) comprises at least a second roller (103), which is supported on the frame (160), and a belt (102), which is guided at least around the two rollers (101, 103) and because of the tension of which a resulting belt force (102) acts on the roller carrier (401). The device (100) also comprises an actuator (302), which is mechanically coupled to the frame (160) and the roller carrier (401) in such a way that an adjustable actuator force (FA) acts between the frame (160) and the first roller (101) in the first direction (x). The belt (102) is guided by means of the second roller (103), or by means of the second roller (103) and further rollers (101a, 101b, 121a, 121b, 105), in such a way that the resulting belt force (FB, FB) acting on the roller carrier (401) acts approximately in a second direction (y) orthogonal to the first direction (x) in the case of a target deflection of the actuator (302).

Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

Method and apparatus for sharpening a cutting tool. In some embodiments, an abrasive endless belt is rotated in tension along a neutral plane between spaced apart first and second rollers. A guide assembly has spaced apart first and second guide surfaces which collectively converge to an intervening base surface to form a guide channel. Upon insertion of a blade of a cutting tool into the guide channel, a selected side of the blade contactingly slides against at least a selected one of the first or second guide surfaces and a first portion of a cutting edge of the blade contactingly engages the base surface to serve as a plunge depth limit stop for the blade. The endless belt is contactingly deflected by a second portion of the cutting edge away from the neutral plane to sharpen the second portion while the first portion remains in contact with the base surface.

The belt sander includes a gear casing coupled to a tool housing, the gear casing surrounding one or more gears configured to receive input from a motor to drive a shaft about a drive axis. The belt sander includes a belt arm assembly having a belt arm, the belt configured to translate in response to input from the shaft. The belt sander includes a plurality of incrementally spaced apart receivers on the gear casing and an engagement member in operational communication with the belt arm assembly, the engagement member being movable between a locked position and an unlocked position, wherein in the locked position the engagement member engages a receiver to fix the belt arm assembly incrementally relative to the gear casing, and wherein in the unlocked position the belt arm assembly freely rotates relative to the belt arm assembly to pivot the belt arm about the drive axis.

Method and apparatus for sharpening a cutting tool having a blade portion with a cutting edge, such as but not limited to a kitchen knife. In some embodiments, a powered sharpener has an abrasive medium that is advanced by a motor and an edge guide surface adjacent the abrasive medium, wherein the cutting edge of the cutting tool is sharpened by bringing a first portion of the cutting edge into contacting engagement with the edge guide surface and drawing a second portion of the cutting edge across the abrasive medium. A plurality of spaced apart channels are formed in the sharpened cutting edge by contactingly engaging the sharpened cutting edge with a cold forging member with sufficient force to displace portions of the sharpened cutting edge. The channels in the sharpened cutting edge constitute locally deformed, work hardened notches.

A tool sharpener has a guide assembly to support a cutting tool adjacent an abrasive medium. A drive assembly advances the abrasive medium with respect to the guide assembly. A control mechanism provides a first control input value to move the medium and achieve a first material take off (MTO) rate during a coarse sharpening operation upon the tool. A second control input value from the control circuit moves the medium to achieve a lower, second MTO rate during a fine sharpening operation. The control mechanism transitions the medium from the first MTO rate to the second MTO rate responsive to a timer mechanism indicating a conclusion of a predetermined elapsed time interval.

An oscillating device of a belt sander is disclosed. The belt sander includes a base, a rotating unit, an oscillating unit, and a control unit. The rotating unit is disposed on one side of the base. The rotating unit includes a motor and a roller. The oscillating unit is disposed on the other side of the base. The oscillating member includes a rolling wheel and an electric motor. The motor and the electric motor drive the roller and the rolling wheel to rotate, and the control unit controls the oscillation frequency of the electric motor. The service life of the motor and the electric motor can be prolonged, thereby improving the working efficiency of the belt sander.

An oscillating device of a belt sander is disclosed. The belt sander includes a base, a rotating unit, an oscillating unit, and a control unit. The rotating unit is disposed on one side of the base. The rotating unit includes a motor and a roller. The oscillating unit is disposed on the other side of the base. The oscillating member includes a rolling wheel and an electric motor. The motor and the electric motor drive the roller and the rolling wheel to rotate, and the control unit controls the oscillation frequency of the electric motor. The service life of the motor and the electric motor can be prolonged, thereby improving the working efficiency of the belt sander.

A hand-held sanding device for sanding a work piece. The sanding device includes a frame adapted for a manual grip and a sanding material provided within the frame for movement relative to the frame. The sanding material forms a sanding surface for the device. The sanding material moves relative to the frame through contact between the sanding surface and the work piece.