Abstract
A member replacement device includes: an operational member ( 9 ) which is rotatably accommodated in a recess ( 8 ) formed in a base-end-side end face of a output rod ( 5 ), the operational member ( 9 ) being configured to press and move the output rod ( 5 ) toward the leading end side in the axial direction; and a biasing member ( 10 ) which is provided inside the cylindrical hole ( 6, 7 ) or with which the cylindrical hole ( 6, 7 ) is filled, the biasing member ( 10 ) being configured to press and move the output rod ( 5 ) toward the base end side in the axial direction. The operational member ( 9 ) is pressed and moved by a cam surface ( 25 a ) of a cam rod ( 24 ) inserted into a guide hole ( 23 ).