Study on the Fast Tool Servo (FTS) with the Stiffness Adjustable

This paper introduced a kind of fast tool servo (FTS) that its stiffness is adjustable. Based on in the frame rack, flexible hinge, piezoelectric ceramic driver, tool base, diamond tools and so on, a spring assembly appendixes on. The spring assembly is consisting of spring rack, the sleeve, spring, and lock circle etc. Spring rack is fixed in front of the frame rack; there is a screw hole in the middle of the spring rack; there is also a screw outer side of the sleeve that mounted through the screw hole. The spring is installed inside sleeve; one end of the spring contacts with the bottom of the sleeve, and the other end contacts with the flexible hinge on frame rack. It can adjust the force of the spring that presses to the flexible hinge by rotating the sleeve. Through replaced the spring, it can makes stiffness of the FTS changed. It is verified that the device has the stiffness adjustable function through calculation and simulation.