Patent ID: 10018191

Abstract:
Apparatus configuration in which: a piston (10) is inserted into a housing (1) ascendably and descendably; and pressurized oil supplied to and discharged from a driving chamber (11) arranged above the piston (10). An output rod (15) inserted into an upper wall (2) of the housing (1) protrudes upward from the piston (10). A descent-detecting first detection valve (31) and an ascent-detecting second detection valve (32) arranged outside the periphery of the output rod (15) and in the upper wall (2), circumferentially spaced apart at a predetermined interval. Each first detection valve (31) and second detection valve (32) has an operated portion (49) (79) which faces the piston (10) from above. The apparatus is configured so that pressurized air for detection is supplied through a first supply passage (B1) and a second supply passage (B2) inlets (31a) (32a) of the first detection valve (31) and the second detection valve (32), respectively.