Bosch Rexroth Ag

Frank Hofmann

Konrad Schneider

Michael Reinert

Karl Cords

Peter Lauer

Helmut Behl

Bruno Schneider

Karl Josef Meyer

Hans Wölfges

Götz-Dieter Machat

Karl J H Cords

Helmut Etzel

Dragoljub Djenadija

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

An unlockable non-return valve reduces the tendency of the poppet piston to jam by providing a first insert that has a guide diameter for the poppet piston over just a short section of its end side facing the piston collar, and wherein a supporting ring is arranged axially between the high-pressure seal and the first insert in a receiving element, the diameter of which is substantially smaller than the outside diameters of the inserts, the supporting ring likewise being produced from a metallic material having good sliding properties and being produced with a narrow clearance from the end section of the poppet piston and with a large radial clearance from the receiving element.

Unlockable non-return valve for very high system pressures

Growing community of inventors

Lohr am Main, Germany

Frank Hofmann