Abstract: A vibration applying apparatus associated with an injection molding machine for applying vibrational repetitive movements to a melt of molding materials includes a rod having a tip end received inside a heating cylinder and disposed in the proximity of a nozzle of the heating cylinder, a stationary guide supporting the rod such that the rod is movable back and forth, a rotating shaft being orthogonal to the rod, a drive motor for rotating the rotating shaft, and a cam mechanism acting between the rotating shaft and the rod so as to convert rotary motion of the rotating shaft into linear reciprocal motion of the rod. With the apparatus thus arranged, the tip end of the reciprocating rod applies vibrational repetitive movements to the melt of molding material, thereby lower the viscosity of melt. The frequency of vibrational repetitive movements can be varied by changing the rotational speed of the drive motor.

Abstract: A screw driving mechanism E which uses a hydraulic cylinder (main cylinder) 2 arranged on the same axis with respect to a screw 3 so as to allow the screw 3 to perform frontward and rearward driving. A pair of auxiliary cylinders 4 and 5 are arranged in parallel at both sides of the main cylinder 2, and the forward ends of piston portions 4p and 5p of the auxiliary cylinders 4 and 5 are joined to the forward end of a piston portion 2p of the main cylinder 2 via a joint mechanism 6. This makes it possible to select a plurality of different injection pressures.