Patent ID: 9393506
Filing Date: 2016-07-19
CPC Classification: B01D

Claim Text:
1. A fluid filter having a filter housing and a cover connected detachably thereto, having a replaceable filter insert made up of a hollow cylindrical filter material body and two end plates enclosing said filter material body at its ends, the filter housing having a central standpipe connected thereto arranged to receive the filter insert thereon, the standpipe having on a free side facing the cover an end piece that is axially displaceable relative to the standpipe, the end piece being preloaded by a force acting in an upward direction of expulsion, the end piece, when in its expelled position, is locked by a locking device that prevents it from being pushed further down the standpipe after a limited extent, and a connection of the cover to the filter housing then being prevented, and a radially inwardly extending protruding member, situated on one of the filter insert and a separate protruding member body that can be placed onto the standpipe either before the filter insert or with the filter insert, to move together with the filter insert being provided that actuates the locking device in the unlocking direction when the filter insert is placed onto the standpipe, enabling a pushing down of the end piece on the standpipe, the locking device being formed by locking tabs that form a part of the standpipe or the end piece and that are movable in a radial direction of the standpipe, each having a locking surface pointing in the axial direction of the standpipe and each having a dog protruding radially in the locking direction, and the locking tabs being preloaded by a force acting in the radially outward locking direction, and each locking tab, with its respective locking surface, prevents the end piece in its upward expelled position from being axially pushed down relative to the standpipe, where the locking tabs are capable of being moved by direct engagement with the protruding member in the radial inward direction into their unlocking position, wherein when the filter insert is placed onto the standpipe or when the protruding member body and the filter insert are placed onto the standpipe, the protruding member enters into direct engagement with the dogs, and the locking tabs pivot radially in the unlocking direction, wherein, in order to form a filter circumvention valve, an end face of the end piece, facing the cover-side end plate of the filter insert, is fashioned as a valve body, and wherein the cover-side end plate of the filter insert has a central opening that forms a valve seat, oriented toward the end piece, for the valve body.