Abstract: A double acting and at the limit positions automatically reversing pressure intensifier. A case has a first bore hole and a second bore hole. A pressure intensifier piston slides in the first bore hole of the case and subdivides the first bore hole into two low pressure work spaces and is furnished with two flat control grooves at the outer circumference and with two cylindrical bore holes. Two high pressure pistons are solidly mounted to the case for sliding relative to and inside of the two cylindrical bore holes of the pressure intensifier piston. A check valve is disposed in the pressure intensifier piston and connects the two bore holes. A control slider is disposed in the case and furnished with two flat control grooves about at its middle region which connect to respective front faces of the slider via cross bore holes and axial bore holes in the control slider. A wide bypass groove is disposed on the outside of the control slider.

Abstract: A double admitting pressure intensifier which automatically reverses at its end positions is provided. The pressure intensifier comprises a pressure intensifier piston and a control slider running parallel to the pressure intensifier piston, each disposed in a bore of a casing. The control slider receives a control impulse only at the end of a stroke in order to maintain the pressure intensifier trouble-free under all conditions. This is assured by disposing two pressure pins of different diameter projection into axial bores of the control slider. The pressure pin with the larger diameter is connected to the feed line or, respectively, to the discharge port depending on the position of the pressure intensifier piston. The pressure pin with the smaller diameter is, on the other hand, continuously connected with the feed line.