Patent ID: 7156558

Claim:
A linear motion drive system, comprising: a base; a linear shaft being fixed to said base; a moving body being linearly and reciprocally moved along said linear shaft; a contact body contacting said linear shaft; and a pressure unit being provided to said moving body, said pressure unit pressing said contact body so as to apply pressure to said linear shaft, wherein said pressure unit includes: a press section contacting and pressing said contact body toward said linear shaft; a biasing member biasing the press section toward said linear shaft; and a locking mechanism holding the press section so as not to move away from said linear shaft, and wherein the press section includes: a first screw member being capable of moving toward said contact body but being prohibited to rotate, the first screw member having one end, which directly or indirectly contacts said contact body, and the other end, in which a screw section is formed; and a second screw member having a screw section screwed with the screw section of the first screw member, the second screw member moving the first screw member toward said contact body when the second screw member is rotated in a prescribed direction, wherein said biasing member is a spiral spring, whose one end is fixed to said pressure unit and whose the other end is fixed to the second screw member, the spiral spring biasing the second screw member in a prescribed rotational direction, and wherein said locking mechanism is constituted by the screw sections of the first and second screw members.