Abstract: An encoder having an oil mist prevention structure includes: an encoding body including a cylindrical base, a light emitter and a secondary encoding piece; an oil-containing bearing received and fixed in the cylindrical base; a shaft penetrating the oil-containing bearing to protrude beyond an end surface of the bearing; a rotary disk fixed onto the shaft to cover one side of the secondary encoding piece; a light acceptor fixed to the cylindrical base to correspond to the light emitter and the secondary encoding piece, thereby receiving the signals emitted by the light emitter; and an oil mist prevention structure including a mask integrally formed with the shaft and exposed beyond an end surface of the bearing and a ring extending from the mask for covering an outer periphery of the bearing.

Abstract: In a rotatable positioning pivot structure and a driver having the pivot structure, the pivot structure includes a casing and a cover movably assembled with the casing. The casing is provided with an opening. One side of the opening is provided with a positioning shaft. The positioning shaft is provided with a positioning portion. One side of the cover is provided with an elastic piece. The elastic piece is provided with a through trough, and an elastic arm is formed in the through trough. The positioning shaft of the casing penetrates the through trough of the cover and is located inside the elastic arm. The inside of the elastic arm is provided with at least one positioning slot to be engaged with the positioning portion of the positioning shaft. With the above arrangement, the rotation of the cover can be positioned. Further, the pivot structure is arranged in the driver.

Abstract: An encoder having an oil mist prevention structure includes: an encoding body including a cylindrical base, a light emitter and a secondary encoding piece; an oil-containing bearing received and fixed in the cylindrical base; a shaft penetrating the oil-containing bearing to protrude beyond an end surface of the bearing; a rotary disk fixed onto the shaft to cover one side of the secondary encoding piece; a light acceptor fixed to the cylindrical base to correspond to the light emitter and the secondary encoding piece, thereby receiving the signals emitted by the light emitter; and an oil mist prevention structure including a mask integrally formed with the shaft and exposed beyond an end surface of the bearing and a ring extending from the mask for covering an outer periphery of the bearing.