| 摘要 |
<p>This invention relates to a clamping mechanism of a molding machine used to injection-mold a synthetic resin. The clamping mechanism is provided with a clamping cylinder having a rear chamber the inner diameter of which is larger than that of a front chamber therein, and a communication clearance between the circumferential wall of the rear chamber in the clamping cylinder and a piston; and the piston having an outer diameter that permits the piston to be fitted in the front chamber in the clamping cylinder, and front and rear portions with a clamping ram and a booster ram coaxially provided thereon. A charging cylinder provided with a piston rod operatively connected to the clamping ram is formed on a side portion of the clamping cylinder so as to communicate with the front chamber therein. The charging surface area of the charging cylinder is set smaller than the area of the end surface of the clamping ram forming the rear surface of the piston. A part of the pressure oil in the cylinder is charged in accordance with the movement of the clamping piston so as to prevent the occurrence of cavitation during a high-speed movement of the clamping ram.</p> |
