FUEL FILTER

• US 20110147290A1
• Filed: 07/16/2009
• Published: 06/23/2011
• Est. Priority Date: 08/18/2008
• Status: Active Grant

• Current Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Original Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Inventors: Braunheim, Michael
• Granted Patent: US 8,673,138 B2
• Time in Patent Office: Days
• US Class Current: 210/172.1
• CPC Class Codes: B01D 36/005 Liquid level sensing means, e.g. for water in gasoil-filters
• CPC Class Codes: B01D 36/008 Means to filter or treat the separated liquid
• CPC Class Codes: F02M 37/28 with means activated by the presence of water, e.g. alarms or means for automatic drainage
• CPC Class Codes: F02M 37/34 by the filter structure, e.g. honeycomb, mesh or fibrous

Abstract

A fuel filter includes a filter element disposed in a filter housing. The filter element is penetrated by fuel flowing in a radial direction from a raw end to a pure end. The fuel filter has a first water separator and a smooth-flow second water separator disposed in series with and connected to the first water separator. Fuel is discharged from the second water separator by a pressure difference generated in the fuel filter.

Claims

1. A fuel filter comprising:

a filter element disposed in a filter housing being penetrated by a fuel flow in a radial direction from a raw end to a pure end a first water separator, and

a smooth-flow second water separator disposed in series with and connected to the first water separator, wherein fuel is discharged from the second water separator by a pressure difference generated in the filter.

2. The fuel filter according to claim 1,

further comprising a fuel discharge line connecting the second water separator via a throttle device to a a fuel tank.

3. The fuel filter according to claim 1,

further comprising a fuel discharge line connecting the second water separator via a venturi nozzle to an inlet line of the fuel filter.

4. The fuel filter according to claim 1,

wherein a flow of discharged fuel from the second water separator is lower by a factor of approximately 1/20 to 1/200 than the flow of fuel through the fuel filter.

5. The fuel filter according to claim 1,

wherein the first and the second water separators are connected at the pure end of the fuel filter and

the fuel discharge takes place at the raw end of the fuel filter.

6. The fuel filter according to claim 1,

further comprising at least one water sensor disposed in the second water separator and configured to detect a water level.

7. The fuel filter according to claim 1,

wherein the first and the second water separators are disposed below the filter element of the fuel filter.

8. The fuel filter according to claim 1,

further comprising a valve device having at least two redundant and controllable valves connected in series at a water drain of the second water separator, the valve device configured to drain water if both valves are open.

9. The fuel filter according to claim 8,

further comprising an absorption filter disposed in the water drain of the second water separator the filter being an activated carbon filter.

10. The fuel filter according to claim 1,

wherein the second water separator is configured to facilitate a laminar flow of a fuel-water mixture.

11. The fuel filter according to claim 1,

wherein the fuel discharge from the second water separator is continuous.

12. The fuel filter according to claim 1,

wherein any combination of the filter element and the first water separator and the second water separator (11) are formed as at least one of:

separate components and as a single combination component.

13. The fuel filter according to claim 1, wherein the filter is disposed in an internal combustion engine.

14. The fuel filter according to claim 2, wherein a flow of discharged fuel from the second water separator is lower by a factor of approximately 1/20 to 1/200 than the flow of fuel through the fuel filter.

15. The fuel filter according to claim 14, wherein the first and the second water separators are connected at the pure end of the fuel filter and the fuel discharge takes place at the raw end of the fuel filter.

16. The fuel filter according to claim 15, further comprising at least one water sensor disposed in the second water separator and configured to detect a water level.

17. The fuel filter according to claim 16, wherein the first and the second water separators are disposed below the filter element of the fuel filter.

18. The fuel filter according to claim 17, further comprising a valve device having at least two redundant and controllable valves connected in series at a water drain of the second water separator, the valve device configured to drain water if both valves are open.

19. The fuel filter according to claim 18, wherein an absorption filter is disposed in the water drain of the second water separator, the filter being an activated carbon filter.

20. The fuel filter according to claim 19, wherein the second water separator is configured to facilitate a laminar flow of a fuel-water mixture.