Filter Element and Filter System

Abstract

A filter element for filtering a fluid has a frame and at least one filter bellows arranged in the frame and provided with a first areal inflow surface for a first fluid flow and at least one second inflow surface for a second fluid flow separate from the first fluid flow. The second inflow surface is separate from the first areal inflow surface. A flow channel is provided to guide the second fluid flow and has a raw-side flow channel section arranged within the frame. A filter system provided with a filter housing is provided with such a filter element arranged exchangeably in the filter housing between a raw side and a clean side. The filter housing has a first inlet for the first fluid flow communicating with the first inflow surface and at least a second inlet for the second fluid flow communicating with the second inflow surface.

Claims

1. A filter element for filtering a fluid, the filter element comprising: a frame; at least one filter bellows arranged in the frame and comprising a first areal inflow surface for a first fluid flow of the fluid and at least one second inflow surface for a second fluid flow of the fluid separate from the first fluid flow of the fluid, wherein the at least one second inflow surface is separate from the first areal inflow surface; a flow channel configured to guide the second fluid flow of the fluid, wherein the flow channel comprises a raw-side flow channel section arranged within the frame.

2. The filter element according to claim 1, wherein the raw-side flow channel section adjoins an end face of the at least one filter bellows or adjoins a narrow side of the at least one filter bellows.

3. The filter element according to claim 1, wherein the at least one flow channel section comprises a segment parallel to or at a slant to a narrow side of the at least one filter bellows and a segment parallel to or at a slant to a flat side of the at least one filter bellows.

4. The filter element according to claim 1, further comprising a cover element covering the raw-side flow channel section at an end face and covering the at least one second inflow surface.

5. The filter element according to claim 1, wherein the frame comprises a seal surface configured to seal the at least one filter bellows and the raw-side flow channel section against a filter housing and configured to seal between an outflow side of the at least one filter bellows and the raw-side flow channel section.

6. The filter element according to claim 1, wherein the frame, the at least one filter bellows, and the flow channel section together form a drawer filter element.

7. A filter system for filtering a fluid, the filter system comprising: a filter housing; a filter element arranged exchangeably in the filter housing between a raw side of the filter system and a and a clean side of the filter system; the filter element comprising a frame and at least one filter bellows arranged in the frame, wherein the at least one filter bellows comprises a first areal inflow surface for a first fluid flow of the fluid and at least one second inflow surface for a second fluid flow of the fluid separate from the first fluid flow of the fluid, and wherein the at least one second inflow surface is separate from the first areal inflow surface; the filter housing comprising a first inlet for the first fluid flow of the fluid communicating with the first inflow surface and at least one second inlet for the second fluid flow of the fluid communicating with the at least one second inflow surface; a raw-side flow channel extending from the at least one second inlet of the filter housing to the at least one second inflow surface and configured to guide the second fluid flow of the fluid; the raw-side flow channel comprising a flow channel section, wherein the flow channel section is arranged inside the filter element.

8. The filter system according to claim 7, wherein the raw-side flow channel extends from the at least one second inlet to the at least one second inflow surface across at least a part of a flat side of the filter bellows and/or wherein the raw-side flow channel extends from the at least one second inlet to the at least one second inflow surface through at least a part of a rim segment of the filter element.

9. The filter system according to claim 7, wherein a valve is arranged in the at least one second inlet for the second fluid flow of the fluid in a housing part of the filter housing.

10. The filter system according to claim 9, wherein the valve is pressure-controlled or controlled by a flow resistance to enable an inflow of the fluid.

11. The filter system according to claim 7, wherein the flow channel comprises at least one flow deflection for the second fluid flow of the fluid between the at least one second inlet and the at least one second inflow surface.

12. The filter system according to claim 11, wherein the at least one flow deflection is a flow reversal.

13. The filter system according to claim 7, wherein the filter element is a drawer filter element configured to be inserted transversely to a main flow axis of the fluid into the filter housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Further advantages result from the following drawing description. In the drawings, embodiments of the invention are illustrated. The drawings, the description, and the claims contain numerous features in combination. A person of skill in the art will consider the features expediently also individually and combine them to expedient further combinations.

[0043] FIG. 1 shows a sectioned isometric illustration of a filter system with mounted drawer filter element according to an embodiment of the invention with inflow surfaces for a first and a second fluid flow.

[0044] FIG. 2 shows a detail view of the filter system according to FIG. 1 in the region of the second inflow surface.

[0045] FIG. 3 shows an isometric illustration of the housing part with an inlet for the second fluid flow of the filter system according to FIG. 1.

[0046] FIG. 4 shows an isometric illustration of the filter element of the filter system according to FIG. 1.

[0047] FIG. 5 shows a sectioned isometric illustration of the filter element of the filter system according to FIG. 1.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0048] In the Figures, same or same-type components are identified with the same reference characters. The Figures show only examples and are not to be understood as limiting.

[0049] FIG. 1 shows a sectioned isometric illustration of a filter system 100 with mounted drawer filter element 10 according to an embodiment of the invention with inflow surfaces 54, 56 for a first and a second fluid flow 60, 62, while in FIG. 2 a detail view of the filter system 100 according to FIG. 1 in the region of the second inflow surface 56 is illustrated. FIG. 3 shows an isometric illustration of the housing part 112, here, for example, the housing top part 112, with the inlet 106 for the second fluid flow 62 of the filter system 100 according to FIG. 1.

[0050] The filter system 100 comprises a filter housing 110 with a first housing part 112, for example, a housing top part 112, and a second housing part 114, for example, a housing bottom part 114, as well as a filter element 10 for filtering a fluid arranged exchangeably in the filter housing 110 between a raw side 50 and a clean side 52. The filter element 10 comprises in this context a one-piece filter bellows 12, for example, with a raw-side inflow side 66 and a clean-side outflow side 68. The inflow side 66 comprises a first areal inflow surface 54 for a first fluid flow 60 as well as a second inflow surface 56 for a second fluid flow 62 separate from the first fluid flow 60. The fluid flows 60, 62 are indicated by wide arrows. The second inflow surface 56 in this example is formed by a rim segment 30 of the filter bellows 12. The rim segment 30 can be flowed through along a flow direction 58 as well as at a slant thereto.

[0051] The first fluid flow 60 enters the filter housing 110 at the raw side 50 through a first inlet 102 of the housing bottom part 114 and flows then via the first inflow side 54 through the filter bellows 12 in a flow direction 58 toward the clean side 52. Via an inlet 106 in which an optional valve 116 is arranged, the second fluid flow 62 enters a flow channel 130 through which the second fluid flow 62 is guided to the second inflow surface 56. Both fluid flows 60, 62 exit again through the outlet 104 from the filter housing 110. The second inflow surface 56 is fluid-tightly separated from the first inflow surface 54 by a separation element 44 and a cover element 46 connected thereto. The cover element 46 is, for example, pushed onto the separation element 44 and the frame 28.

[0052] The flow channel 130 comprises a flow channel section 132 adjoining the filter bellows 12 of the filter element 10. Filter bellows 12 and flow channel section 132 are surrounded together by a frame 28, in particular the frame 28 is molded around them. The cover element 46 closes off the flow channel section 132 at the end face. The flow channel section 132 guides the raw-side second fluid flow 62 past the filter bellows 12. Due to a flow reversal, the second fluid flow 62 reaches the second inflow surface 56. The inlet 106 is positioned at the side of the filter bellows 12 which is positioned opposite the two inflow surfaces 54, 56.

[0053] The frame 28 comprises a seal surface 38 on which a seal 40 in the form of a loop element is arranged which seals against the corresponding housing seal surface 160 of the filter housing 110. The flow channel section 132 of the flow channel 130 is arranged between filter bellows 12 and an end face wall 138 of the frame 28.

[0054] The separation element 44 is attached to the folds 34 of the filter bellows 12, for example, glued on. The separation element 44 is connected to the cover element 46 for areal coverage of the second inflow surface 56 against the first fluid flow 60. The cover element 46 is pushed onto the separation element 44 and the end face wall 138 of the frame 28.

[0055] In this example, the filter element 10 with the filter bellows 12 is configured as a flat filter in the form of a drawer filter element. For this purpose, the filter housing 110 comprises an insertion compartment 146 with a frame guide 158 for the filter element 10 by means of which the filter element 10 can be inserted through an insertion opening 144 of the filter housing 110 transversely to the flow direction 58 into the insertion compartment 146 so that a seal 40 of the filter element 10 rests circumferentially against a housing seal surface 160 and seal-tightly relative to the main flow axis 128 of the fluid in an axial direction. The flow direction 58 is parallel to the main flow axis 128. The flow direction 58, for example, is oriented here perpendicularly to the inflow surfaces 54, 56 and outflow side 68 or outflow surface. Preferably, outflow surface and inflow surface in a filter bellows 12 with erected folds 34 form the surfaces in which respectively the inflow-side and outflow-side fold edges 26 (FIG. 2) are positioned.

[0056] Optionally, other geometries of the filter element 10 instead of a flat filter can be provided also, for example, a stepped filter element.

[0057] In the housing top part 112 of the filter housing 110, the inlet 106 for the second fluid flow 62 is embodied with a valve 116 for the second fluid flow 62. The valve 116 is arranged at the second inlet 106 and can be designed, for example, as a check valve. An inflow of the fluid through the valve 116 can be realized in this context by pressure control or controlled by a flow resistance. The valve 116 is however not mandatorily required for the function of the second inflow surface 56 as separate filtration region for an emergency operation when the inflow surface 54 is clogged.

[0058] FIG. 3 shows an isometric illustration of the housing top part 112 of the filter system 100 according to FIG. 1. The housing top part 112 comprises the clean-side outlet 104 of the fluid of the filter housing 110 and the second inlet 106 for the second fluid flow 62 (see FIGS. 1 and 2). The housing seal surface 160 of the filter housing 110 can be seen against which the filter element 10 can be sealed with a seal 40 in the form of a loop element. A web 162 of the housing seal surface 160 is arranged between the clean-side region for the filter bellows 12 and the raw-side region for the flow channel section 132.

[0059] The housing part 112 comprises laterally an insertion opening 144 for the filter element 10 which is embodied as a drawer filter element.

[0060] In FIG. 4, an isometric illustration of the filter element 10 of the filter system 100 according to FIG. 1 is shown while FIG. 5 shows a sectioned isometric illustration of the filter element 10. The filter element 10 is embodied as a flat filter in the form of a drawer filter element and comprises, in addition to the filter bellows 12 with molded-on plastic frame with flow channel section 132, at one end a closure element 42 with which an insertion opening 144 in the filter housing 110 is closed. The sealing action between raw side 50 and clean side 52 of the filter system is realized by the seal 40 which is arranged on the frame 28 and which seal-tightly contacts the housing seal surface 160 (FIG. 2) in the mounted state.

[0061] The filter bellows 12 of the filter element 10 is folded in a zigzag shape to folds 34 with parallel fold edges 26 embodied at the inflow side and outflow side, respectively, which sequentially follow each other in a longitudinal extension 14 between oppositely positioned end face edges 22, 23 of the filter bellows 12 and extend between oppositely positioned sides of the filter bellows 12, respectively.