Bosch Rexroth Ag

Karl Josef Meyer

Peter Lauer

Konrad Schneider

Karl Cords

Hans Wölfges

Frank Hofmann

Günter Krenzer

Götz-Dieter Machat

A pilot-operated pressure shut-off valve having a main control piston which, when an upper system limit pressure in the hydraulic system is reached, connects an inlet, via which pressure medium can be fed to a hydraulic system, to an outlet by taking up a first switching position and, when a lower system limit pressure is reached, separates from the outlet by taking up a second switching position. The pressure shut-off valve has a pilot valve arrangement by which the fluidic connection of a control space adjacent to the main control piston can be changed in order to control the main control piston, and which has a valve housing, with a first pilot piston and a second pilot piston accommodated within the first pilot piston for compact construction and capability to adjust the two pilot pistons mechanically completely independently of each other.

Pilot-operated pressure shut-off valve

A hydraulic device having a nut part with a threaded hole which has an internal screw thread with a defined nominal diameter and with a defined, uniform pitch, and having a screw part which has an external screw thread with the same nominal diameter as the threaded hole and with a defined, uniform pitch, which is screwed into the threaded hole. (In hydraulic devices, screw parts, in particular nozzle bodies, are generally adhesively bonded in place, in order to prevent them from becoming detached. Adhesive bonding has certain drawbacks, since the screw threads have to be free of grease, and in the case of nozzles there is a risk of blockages, adhesive can enter the hydraulic circuit and also process reliability is not ensured during application.) There is provided a slight difference between the pitch of the internal screw thread of the nut part and the pitch of the external screw thread of the screw part. This slight difference in pitch while the screw part is being screwed in leads to an elastic deformation of a plurality of thread turns, with the result that the screw part is secured so that it cannot become detached.

Hydraulic device

Growing community of inventors

Rieneck, Germany

Karl Josef Meyer