Pilot-controlled valve having a ceramic control piston

摘要

A pilot-controlled valve having a valve system switches a pressure medium flow between at least one working connection, a supply pressure connection and a ventilation connection, and includes at least one valve member of ceramic material operated rotationally/linearly by pilot control, at least one connecting channel is bringable into flow connection to the working connection, which, based on the valve member's position, produces a flow connection of the working connection to a first flow channel connected to the ventilation connection or to a second flow channel that is connected to the supply pressure connection, at least one section of the first and second flow channels being in at least one static valve body of ceramic material, at least the first flow channel is sealed from the second flow channel by at least one seal that is in a region outside a direct inflow by the pressure medium.

主权项

1. A pilot-controlled valve, comprising:
a valve system which switches a pressure medium flow between at least one working connection, one supply pressure connection and one ventilation connection; wherein the valve system includes at least one valve member and valve elements, the valve elements being made of ceramic material, and which is operated linearly by pilot control, wherein in the valve member, at least one connecting channel is able to be brought into flow connection to the working connection, which, as a function of the position of the valve member, produces a flow connection of the working connection to a first flow channel that is in connection to the ventilation connection, or to a second flow channel that is in connection to the supply pressure connection, at least one section of the first flow channel and of the second flow channel being configured in at least one valve element made of ceramic material, wherein at least the first flow channel is sealed from the second flow channel by at least one seal that is situated in a region outside a direct inflow by the pressure medium, so that the stressing of the seal goes down when the valve has large volumes of pressure medium flowing through it and the pressure medium is contaminated with particles, wherein the pilot-controlled valve is a pressure-regulating valve for a compressed air braking system of a vehicle, wherein the at least one seal is elastically pre-stressed in a direction that improves the sealing effect, wherein the at least one seal is situated at a radial distance from an orifice of the first or second channel, wherein the valve member is made of ceramic material that is linearly operated by a control piston, in which the at least one connecting channel is developed and the valve element includes at least two valve elements made of ceramic material, that form a linear guidance for the valve member, between which the valve member is situated, wherein the other element of the valve element has a third flow channel that is in connection to the working connection and a fourth flow channel that is in connection to the working connection, and the one element of the valve element has the first flow channel and the second flow channel, in the valve member at least two connecting channels being configured so that, in at least one setting of the valve member, no flow connection comes about between the first flow channel or the second flow channel to the working connection, but a setting of the valve member exists in which the first flow channel is in flow connection to the working connection, as well as an additional setting of the valve member, in which the second flow channel is in flow connection to working connection, wherein the valve member, the one valve element and the other valve element are supported by a retaining body in a recess of a valve housing, in the retaining body at least one section of the at least one flow channel is developed of the group including the first flow channel, the second flow channel, the third flow channel and the fourth flow channel, wherein the retaining body is a plurality of parts, and wherein a spring arrangement is provided between the valve housing and at least one part of the retaining body so that the valve member is biased by the spring arrangement, in which orifices of at least one of the first flow channel and the second flow channel are developed, and wherein the prestressing by spring arrangement occurs in a direction parallel to the linear motion of the valve member.