Fuel supply system and fuel filter

Abstract

A fuel supply system for an internal combustion engine may include a water separator configured to separate a polar phase, for example water, out of fuel. The water separator may be arranged at least one of on and in a fuel supply system component. The water separator may be configured as an electric coalescer. The electric coalescer may have at least two electrodes that are insulated from the fuel.

Claims

1. A fuel filter device for a fuel supply system of an internal combustion engine, comprising: a water separator configured as an electric coalescer to separate a polar phase out of fuel; and a filter housing in which the electric coalescer is arranged; and a filter element arranged in the filter housing and configured to clean the fuel after water has been separated therefrom; wherein the electric coalescer has at least two electrodes that are insulated from the fuel.

2. The fuel filter device according to claim 1, wherein the electric coalescer has at least one of a DC input voltage of 0-5000 V, a pulsed DC voltage of 0-5000 V and an AC input voltage of 0-40,000 V.

3. The fuel filter device according to claim 2, wherein at least one of the pulsed DC voltage has a frequency of 0-10,000 Hz and the AC input voltage has a frequency of 0-10,000 Hz.

4. The fuel filter device according to claim 2, wherein the electric coalescer has the DC input voltage of 0-5000 V.

5. The fuel filter device according to claim 2, wherein the electric coalescer has the pulsed DC voltage of 0-5000 V.

6. The fuel filter device according to claim 2, wherein the electric coalescer has the AC input voltage of 0-5000 V.

7. The fuel filter device according to claim 1, wherein the electric coalescer is arranged in the filter housing, and wherein the electric coalescer is disposed at least one of in a region of a heating device, on a water level sensor, on the filter element and in a filter device line.

8. The fuel filter device according to claim 1, further comprising a control device configured to at least one of activate the electric coalescer and set a separation rate of the electric coalescer.

9. The fuel filter device according to claim 8, wherein the control device is configured to set at least one of the following parameters: an electric field, a field strength and a frequency.

10. The fuel filter device according to claim 1, wherein the polar phase is water.

11. A fuel supply system for an internal combustion engine, comprising: a water separator configured to separate a polar phase out of fuel, the water separator arranged in a filter housing; and a filter element arranged in the filter housing and configured to clean the fuel after the polar phase has been separated therefrom; wherein the water separator is configured as an electric coalescer, and wherein the electric coalescer has at least two electrodes that are insulated from the fuel.

12. The fuel supply system according to claim 11, further comprising at least one of a main tank, a pre-filter, an additional tank, a fuel line and a main filter.

13. The fuel supply system according to claim 11, wherein the electric coalescer has at least one of a DC input voltage of 0-5000 V, a pulsed DC voltage of 0-5000 V and an AC input voltage of 0-40,000 V.

14. The fuel supply system according to claim 13, wherein at least one of the pulsed DC voltage has a frequency of 0-10,000 Hz and the AC input voltage has a frequency of 0-10,000 Hz.

15. The fuel supply system according to claim 13, wherein the electric coalescer has the DC input voltage of 0-5000 V.

16. The fuel supply system according to claim 13, wherein the electric coalescer has the pulsed DC voltage of 0-5000 V.

17. The fuel supply system according to claim 13, wherein the electric coalescer has the AC input voltage of 0-5000 V.

18. The fuel supply system according to claim 11, further comprising a control device configured to at least one of activate the electric coalescer and set a separation rate of the electric coalescer.

19. The fuel supply system according to claim 18, wherein the control device is configured to set at least one of the following parameters: an electric field, a field strength and a frequency.

20. A fuel supply line for an internal combustion engine, comprising: a filter housing; a water separator configured to separate water from fuel; and a filter element arranged in the filter housing and configured to clean the fuel after the water has been separated therefrom; wherein the water separator is arranged in a filter housing; wherein the water separator is configured as an electric coalescer, the electric coalescer including at least two electrodes that are insulated from the fuel; and a control device in communication with the electric coalescer and configured to at least one of activate the electric coalescer and set a separation rate of the electric coalescer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the figures,

(2) FIG. 1 schematically shows a fuel filter device according to the invention in a sectional diagram,

(3) FIG. 2 schematically shows a fuel supply system for an internal combustion engine.

DETAILED DESCRIPTION

(4) According to FIG. 1, a fuel filter device 1 according to the invention has a customarily annular filter element 2, through which flow passes from the outside inwards in the present case. The interior, i.e. a clean side of the filter element 2, is fluidically connected to an outlet 3, whereas the outside of the filter element 2, i.e. the untreated side, is connected to a feed 4. A water separator 5 is likewise provided, which according to the invention is in the form of an electric coalescer 5. The electric coalescer 5 can have two electrodes 6 and 7, which are insulated from the actual fuel, of which electrodes the electrode 7 is arranged inside a filter housing 8 as in the case shown. An individually adjustable water separation rate can then be achieved by supplying the electric coalescer 5 with current, the water separator 5 in the form of an electric coalescer 5 according to the invention also having the great advantage of not having to be replaced according to schedule, but being able to remain in the fuel filter device 1 over the entire service life of the fuel filter device 1, i.e. therefore also over several service lives of filter elements 2.

(5) As can be seen in FIG. 1, some of the electric coalescer 5 is arranged in the filter housing 8, it of course also being conceivable for the electric coalescer to be arranged in the region of a heating device, in the region of a water level sensor, in/on the filter element 2 and/or in a line, for example the feed 4 or the outlet 3. In the present case, it is arranged partially in the filter housing 8 and partially in an annular space between said housing and the filter element 2. The water that coagulates in this region settles, owing to its greater density, in a water collection space 9 arranged at the bottom, from which the water can be drained according to schedule, for example by means of a water drainage screw 10.

(6) According to the invention, a control device 11 is also provided, by means of which the water separator 5, i.e. the coalescer, can be activated and in particular the separation rate of the water separator can be set. The control device 11 can be used for example to set a field strength between the individual electrodes 6, 7 or else a frequency.

(7) The water separator 5 according to the invention thus ensures effective and efficient separation of water out of the fuel to be filtered and guarantees consistently good separation values over the entire service life of the fuel filter device 1. It can be seen in FIG. 1 that the two electrodes 6 and 7 are of course arranged such that they are insulated from the fuel, so that the fuel does not come into direct contact with the electrodes 6, 7.

(8) FIG. 2 shows a fuel supply system 12 according to the invention for an internal combustion engine 19, having a water separator 5 in the form of an electric coalescer 5 in order to separate a polar phase, in particular water, out of the fuel, which water separator is arranged on or in a component 13 of the fuel supply system 12. The component 13 can be in the form of a main tank 14, pre-filter 15, additional tank 16, fuel line 17 or main filter 18. Of course, the electric coalescer 5 can also be arranged as a separate water separator 5 at any point in the fuel supply system 12.