Patent ID: 6695121
Filing Date: 2004-02-24
Classification: B23Q,B65G,F16C,F16H

Abstract:
A dustproof linear actuator comprising:a housing, having a first axial end and a second axial end opposite to said first axial end, with a slit extending axially from said first axial end to said second axial end; a linear guide device disposed in the housing; a carriage mounted in the housing and axially movable along the slit by the linear guide device, the carriage including a workpiece mounting table protruding from the housing through the slit; a linear drive device disposed in the housing for moving the carriage axially, wherein when said linear drive device axially moves the carriage towards one of said first and second axial ends, air disposed between the carriage and said one of the ends within said housing is compressed so as to cause an increase in pressure thereof; a pair of pulleys disposed in an axial end of the housing; a sealing band movably mounted around the pulleys within the housing for closing the slit, the sealing band including first and second ends which are fastened to first and second ends of the carriage, respectively, to form a circulative loop; and an air venting device having openings, near said first axial end and said second axial end, for venting air existing in the housing to an outside of the housing, wherein the air venting device comprises first and second air venting pipes disposed in the housing and extending axially to pass through at least one housing end toward the outside of the housing, the first and second air venting pipes having a different length from each other in which the first air venting pipe includes an inner end which is opened close to the first axial end and the second air venting pipe includes an inner end which is opened close to the second axial end of the housing.