Filter element with end face inlets and discharge outlets

#The invention relates to a filter element for end face inflow, comprising alternating flat layers and folded layers which form channels having a triangular cross section, in which the channels are alternately sealed at one end or the other so that the fluid to be filtered must flow through the filter medium. The invention further relates to a filter in which the described filter element is installed.

#Filter elements with end face inlets are already known in the art. These filters are wound, for example, from filter layers that are alternately flat and wavy. This creates channels, the alternating seal of which forces the fluid to flow through the filter medium. Accordingly, the medium to be filtered enters through the channels which are open on the end face at the inlet side. Within the filter element, the medium switches to channels that are adjacent to the inlet channels and are open on the discharge side. This causes the fluid to be filtered.

#The aim of such a filter configuration on the one hand is to minimize the volume required for the filter element. The end faces of the filter element form an inlet side and a discharge side, respectively. The channels that communicate with the inlet side form the unfiltered side of the filter, while the discharge-side channels form the filtered side. As a result, these filters are very compact and can be installed, for instance, as inline filters in pipes. At the same time, the aim is to increase the filter capacity as far as possible. However, with a wavy configuration of the filter layer this is possible only to a limited extent. It has been shown that in the inlet channels there is little flow in the contact area between the wavy filter layer and the flat filter layer, so that fewer particles are deposited on the filter medium in these areas than in others. Due to the irregular loading of the filter medium, the filter reaches the end of its service life, which is determined by the pressure drop across the filter, at a time when parts of the filter medium have not yet reached their loading limit.

#The invention will be described in further detail hereinafter with reference to illustrative preferred embodiments shown in the accompanying drawing figures in which:

#FIG. 1 shows the filter structure in a schematic cross-section through the center of an inline filter with a cylindrical filter element;

#FIG. 2 is a perspective detail view of a filter element with a rectangular configuration;

#FIG. 1 depicts an inline filter with a housing 10 comprising a housing vessel 11 and a cover 12. The cover has an inlet 13 through which the fluid to be filtered flows into the housing in the direction indicated by the arrow. The fluid then flows through a filter insert 14 and through an outlet 15. Filter insert 14 is mounted in a parting plane 16 between the housing vessel 1 land the cover 12 of the housing.

#The schematically depicted filter insert 14 is configured as a wound filter. The different layers 17 and 18 form channels 19 through which the fluid to be filtered flows. The channels are alternately sealed by seals or closures 20a and 20b, so that the fluid to be filtered must switch channels as it flows through the filter insert 14. This causes the fluid to be filtered. The layers 17 and 18 are furthermore wound around a core 21 having e.g., an oval cross section, forming a seal.

#To produce a reliable separation between an inlet side 22 and a discharge side 23, the filter insert is mounted in a filter frame 24, and the filter frame is clamped into the parting plane 16 of the housing between the housing vessel and the cover.