Details for Patent: 7,645,383
✉ Email this page to a colleague
Title: | Microstructured filter |
Abstract: | A microstructured filter is presented having an inlet for unfiltered fluid; an outlet for filtered fluid; a plurality of projections, which form at least one row in a mutually juxtaposed relationship across the filter, that project out of a base plate and are an integral component of the base plate; a plurality of passages between the projections; and a cover plate which is securable to the base plate to cover the projections and the passages. The passages form a plurality of through paths from the inlet to the outlet. The inlet includes an elongate inlet slot for the unfiltered fluid that extends over approximately the entire filter width and is approximately as high as the projection on the outlet side of the filter. |
Inventor(s): | Kadel; Klaus (Willen, DE), Geser; Johannes (Dortmund, DE), Eicher; Joachim (Dortmund, DE), Freund; Bernhard (Gau-Algesheim, DE), Dunne; Stephen Terence (Suffolk, GB), Bachtler; Wulf (Mainz, DE) |
Assignee: | Boehringer Ingelheim International GmbH (Ingelheim, DE) |
Filing Date: | Oct 14, 2005 |
Application Number: | 11/249,268 |
Claims: | 1. A microstructured filter having an inlet for unfiltered fluid and an outlet for filtered fluid, the filter comprising: a substantially flat base plate having a plurality of projections extending therefrom such that each projection is an integral component of the base plate, wherein the projections are spaced from one another by passages that form a fluid path through the filter from the inlet to the outlet; a cover plate securable to the base plate for covering the projections and the passages, wherein the plurality of projections form at least one row which is arranged in a meander configuration in a mutually juxtaposed relationship across the filter; and wherein the passages have a length of 5 .mu.m to 50 .mu.m, a height of 2.5 .mu.m to 25 .mu.m, and a width of 2.5 .mu.m to 25 .mu.m. 2. The filter according to claim 1, wherein a spacing between the base plate and the cover plate is approximately as large as a width of the passages between adjacent projections. 3. The filter according to claim 1, wherein the plurality of projections form a plurality of meandering rows of projections arranged in a cascade relationship, the projections which are arranged closer to the inlet side of the filter are larger than the projections which are arranged more at the outlet side of the filter. 4. The filter according to claim 1, wherein the cover plate is substantially flat. 5. The filter according to claim 1, wherein a spacing between the base plate and the cover plate in the area around the projections within a meandering row of projections is larger in the region of the end of the meandering row which is in the proximity of the outlet side of the filter than in the region of the end of the meandering row which is in the proximity of the inlet side of the filter. 6. The filter according to claim 3, wherein mutually facing sides of two adjacent meandering rows of projections define an interconnected space into which the fluid flows from all passages between the projections of a first row and out of which the fluid flows into all passages between the projections of the row following in the direction of flow. 7. The filter according to claim 1, wherein the projections are in the form of lands which, as viewed in the flow direction, are straight. 8. The filter according to claim 1, wherein the projections are in the form of lands which, as viewed in the flow direction, are curved. 9. The filter according to claim 1, wherein the projections are in the form of lands which, as viewed in the flow direction, are in the form of columns. 10. The filter according to claim 1, wherein the lands are arranged in varying orientations with respect to the flow direction. 11. The filter according to claim 1, wherein the passages are of substantially constant cross-section, and have a length that is at least twice as great as their height on the entry side of the fluid. 12. The filter according to claim 1, wherein the passages are of an approximately constant cross-section over the passage length. 13. The filter according to claim 12, wherein the passages have a substantially square cross-section. 14. The filter according to claim 1, wherein the passages have a combination of barrel-shaped cross-sections and trapezoidal cross-sections. 15. The filter according to claim 14, wherein a longer side of the trapezoidal passages is formed by the cover plate. 16. The filter according to claim 1, wherein the passages have an approximately square cross-section on the entry side of the filter that becomes wider towards the exit side of the filter. 17. The filter according to claim 1, wherein a spacing between the base plate in the area around the projections and the cover plate within a meandering row of projections is substantially constant. 18. The filter according to claim 5, wherein a spacing between the flat base plate in the area around the projections and the cover plate within a meandering row of projections linearly increases from the region of the end of the meandering row which is in the proximity of the inlet side of the filter in a direction towards the region of the end of the meandering row which is in the proximity of the outlet side of the filter. 19. A nebulizer for inhalation therapy, the nebulizer comprising a microstructured filter having an inlet for unfiltered fluid and an outlet for filtered fluid, the filter comprising: a substantially flat base plate and a cover plate that is securable thereto, a plurality of projections that each comprise an integral component of the base plate and which each project therefrom, the projections being spaced from one another by passages that form a fluid path through the filter from the inlet to the outlet, the cover plate when secured to the base plate covering the projections and the passages; wherein the plurality of projections form at least one row which is arranged in a meander configuration in a mutually juxtaposed relationship across the filter; and wherein the passages have a length of 5 .mu.m to 50 .mu.m, a height of 2.5 .mu.m to 25 .mu.m, and a width of 2.5 .mu.m to 25 .mu.m. 20. The nebulizer according to claim 19, comprising a nozzle in assembly with the filter. |