Valve with self-aligning shaft seal

摘要

A valve design that enables a positive shaft seal to be obtained in an inexpensive manner by reducing the need for close tolerances heretofore required in prior art designs. This unique valve design employs a shaft seal that is adapted for transverse and/or angular movement during assembly of the valve for aligning to the shaft at an alignment position in which it is held after assembly of the valve by a holding device such as a seal nut or spring.

主权项

1. A valve comprising:
a spool axially movable within a valve body; a shaft associated with the spool and extending out of the valve body; an adapter having a through hole for receiving the shaft; a shaft seal for sealing against the shaft, wherein the shaft seal is adapted for transverse movement during assembly of the valve for aligning to the shaft at an alignment position and then is held in such alignment position after assembly of the valve; a holding device having a cavity for receiving the shaft and the shaft seal; and a seal carrier for supporting the shaft seal, wherein the seal carrier and shaft seal are unitary, with the seal carrier extending radially outwardly from the shaft seal and being held against a surface of the adapter by the holding device and sealing thereagainst, wherein a maximum outer transverse dimension of the shaft seal is less than an inner transverse dimension of the cavity of the holding device at a location transversely concentric the outer transverse dimension of the shaft seal, after assembly of the valve.