Liquid filter

Abstract

In a liquid filter comprising a filter housing having at least one liquid intake channel and at least one liquid return channel passing through a face wall of the filter housing that faces toward a filter connecting flange to which said filter housing is to be mounted, a releasable cover that closes the filter housing liquid-tight, an individually replaceable filter insert that can removed from the filter housing, and the improvement of a hollow fastening screw forming an axial liquid channel in communication with the liquid return channel and that can be rotated relative to the filter housing, the screw being centrally arranged in the face wall of the filter housing and serving to securely mount the filter housing to the filter connecting flange. Check valves can optionally be provided in the intake channel and in the hollow screw to prevent unwanted flow of liquid through the filter housing, particularly when changing the filter insert. Also, a bypass valve and a bypass filter may be provided to provide for liquid flow through the filter housing when the filter insert prevents sufficient passage of liquid therethrough resulting in an increased pressure across the filter insert.

Dependencies are inferred from the claim text.