Fixing structure of spindle balancer for machine tool technical field

A fixing structure of a spindle balancer for a machine tool for mounting the spindle balancer vertically on the machine tool, the spindle balancer comprising a gas spring having a cylinder body, compressed gas introduced in the cylinder body, and a rod inserted in the cylinder body to receive gas pressure of the compressed gas and biasing vertically movable spindle head of the machine tool upward, the fixing structure comprising:

• an annular flange member integrally fixed to the cylinder body of the gas spring at a lower end portion of the cylinder body so as to extend horizontally outward from an outer periphery of the cylinder body at an upper end of the lower end portion, the annular flange member having a flat supported surface on an underside;
• a support member fixed to a side surface of the spindle head by a plurality of bolts, said support member having on a top surface a flange receiving surface for receiving said flat supported surface, said support member having a mounting hole in which the lower end portion of the cylinder body is fitted in part so as to substantially penetrate said mounting hole to a position at which said flat supported surface of the annular flange member abuts against the flange receiving surface;
• and
• a plural fastening members for fastening the annular flange member to the support member so that the flat supported surface abuts against the flange receiving surface.