Abstract: A motor-operated cylinder is provided, wherein the rotational movement of the output shaft of a motor is converted into a linear movement by a thread mechanism 3, with the least possible load applied to the thread mechanism 3 when an object starts to be moved. The motor-operated cylinder is equipped with a booster 14 so that propelling forces exerted by both the thread mechanism 3 and booster 14 simultaneously act on a retractable rod 6.

Abstract: The electric cylinder consists of an electromotor 1, a plurality of parallel ball screws 4 connected to the electromotor 1 via transmission members 3, a plurality of ball nuts 5 mating with the ball screws 4, a slider 6 for consolidating the ball nuts 5 into one body, and a rod 7 fixedly mounted to the slider 6. The electric cylinder has a high thrust so that it can replace an oil pressure cylinder so that those cylinders used in a plant are unified into electric cylinders to achieve their efficient maintenance.

Abstract: A simplified apparatus of cooling lines is disclosed. A plurality of cooling lines (Z.sub.1 -Z.sub.4) are disposed between two parallel lines, a teeming line (X) and a mold-removing line (V). A mold sending-in line (Y) is disposed to connect the end portion of the teeming line and the starting portions of the cooling lines. A mold sending-out line (U) is disposed to connect the end portions of the cooling lines and the starting portion of the mold-removing line (V). A first transfer device (4) runs along the mold sending-in line (Y), while a second transfer device (6) runs along the mold sending-out line (U). Opposing electric servo-cylinders (15, 29) are mounted on a transfer truck (9) of the first transfer device (4) and a transfer truck (23) of the second transfer device (6).

Abstract: An electric cylinder to reduce shock and damage to itself and a body to be transferred. The electric cylinder includes a rod head having a flange mounted on the distal end of a hollow piston rod, a circular polyurethane rubber plate mounted on a circular front surface of the flange, and a protection plate mounted on the front surface of the polyurethane rubber plate.