PURPOSE: To obtain a press apparatus hardly contaminating the working environment and easy to maintain by using screw feeder mechanism to transfer movable bolster and finite lead pressure generating mechanism to increase die clamping pressure.

CONSTITUTION: The screw 13 is rotated with a motor 7 for shifting, and the movable bolster 4 and a pressing die 9 are lifted to the starting position of increasing die clamping pressure together with a shifting rod 6. A receiver 6 is rotated with a motor 24 for rotating the receiver and stopped at the position where the upper surface of a spline comes into contact with the bottom surface of the spline of a shifting rod 6. A generator 15 is rotated with a motor 8 for increasing pressure, and the receiver 16 and the shifting rod 6 are lifted with the finite lead between the generator and the receiver 16 to obtain a desired pressure. By this method, the press apparatus hardly contaminating the environment, having simple structure, compact and easy to maintain, is obtd.