Patent ID: 7926545

Claim:
An injection cylinder in an injection apparatus for molding a metal material, comprising: a cylinder body, having a first fitting part and a larger-diametered second fitting part in an opening in a front end thereof, a feed opening being formed in a top area of the cylinder body; a cylinder liner of cylindrical form, a flange being formed on a periphery of the front end of the cylinder liner, a feed hole being formed in a predetermined location of a top area of the cylinder liner, the cylinder liner being brought into close contact with an inner surface of the cylinder body by means of thermal expansion with the cylinder liner inserted into the cylinder body from the opening side so that the flange is fitted to the first fitting part and so that the feed hole and the feed opening are in the same position; a nozzle member of cylindrical form, having a nozzle at an extremity thereof and a flange on a periphery of a rear end thereof, the flange being fitted to the second fitting part so that a rear end face of the flange is in contact with a front end face of the flange of the cylinder liner; and a coupling ring arranged around a cylindrical part of the nozzle member, a rear end face of the coupling ring being engaged with a front end face of the nozzle member and fastened to a front end face of the opening of the cylinder body with a bolt, whereby the nozzle member and the cylinder body are tightened to each other with the flange of the cylinder liner interposed therebetween.