PURGE SYSTEM

Abstract

A purge system of a vehicle for purging CH-gas of a tank system to an induction line of a combustion engine of the vehicle. The purge system includes a purge unit, a control unit for operating the purge unit and gas connection lines, wherein a first line end of the gas connection lines is configured for connecting the purge unit with the tank system and a second line end of the gas connection lines is configured for connecting the purge unit with the induction line. The purge system also includes a CH-sensor for measuring a CH-gas concentration of a fluid volume flow that flows from the first line end towards the second line end. A vehicle and a method for operating a combustion engine system of a vehicle with a purge system is also provided.

Claims

1. A purge system of a vehicle for purging CH-gas of a tank system to an induction line of a combustion engine of the vehicle, the purge system comprising: a purge unit; a control unit for operating the purge unit and a gas connection line, a first line end of the gas connection line is configured for connecting the purge unit with the tank system and a second line end of the gas connection line is configured for connecting the purge unit with the induction line; and a CH-sensor for measuring a CH-gas concentration of a fluid volume flow that flows from the first line end towards the second line end.

2. The purge system according to claim 1, wherein the purge unit comprises a purge pump for purging CH-gas from the first line end towards the second line end.

3. The purge system according to claim 1, wherein the purge system further comprises a check valve for preventing a fluid flow from the induction line towards the purge pump.

4. The purge system according to claim 1, wherein the purge unit comprises a purge valve for controlling a volume flow of CH-gas from the first line end towards the second line end.

5. The purge system according to claim 1, wherein the CH-sensor is integrated in the purge pump or the check valve or the purge valve.

6. The purge system according to claim 1, wherein the purge unit comprises a pressure sensor and/or a mass flow sensor for measuring a fluid pressure and/or a fluid mass flow inside the gas connection line between the purge unit and the first line end and/or a temperature sensor for measuring a temperature within the purge system.

7. The purge system according to claim 6, wherein the pressure sensor and/or mass flow sensor and/or the temperature sensor is integrated in the purge pump or the purge valve.

8. The purge system according to claim 1, wherein the control unit is configured to determine a CH-gas volume flow that exits the second line end, based on the measured CH-gas concentration and the fluid volume flow through the gas connection lines.

9. A vehicle comprising: a combustion engine; a tank system for providing the combustion engine with fuel; an induction line for providing the combustion engine with oxygen; and a purge system according to claim 1.

10. A method for operating a combustion engine system of a vehicle with a purge system according to claim 1, the method comprising: measuring by the CH-sensor a CH-gas concentration of a fluid volume flow that flows from the first line end towards the second line end of the purge system; determining a fluid volume flow that flows from the first line end towards the second line end by the control unit; determining a CH-gas volume flow from the measured CH-gas concentration and the determined fluid volume flow by the control unit; and adapting a fuel injection to the combustion engine with respect to the determined CH-gas volume flow.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0026] FIG. 1 schematically shows an exemplary embodiment of a vehicle according to the invention in a top view;

[0027] FIG. 2 schematically shows an exemplary embodiment of a purge system according to the invention; and

[0028] FIG. 3 schematically shows a flow chart of the method according to an exemplary embodiment of the invention.

DETAILED DESCRIPTION

[0029] In FIG. 1, an exemplary embodiment of a vehicle 2 according to the invention is schematically illustrated in a top view. The vehicle 2 comprises a combustion engine system 16. The combustion engine system 16 comprises a tank system 3 with a fuel tank 17 and an active carbon filter 18 for binding CH-gas evading from the tank 17. An air filter 19 of the combustion engine system 16 is connected with the active carbon filter 18 for providing filtered air for flushing the active carbon filter 18. The active carbon filter 18 is connected to a first line end 9 of a gas connection line 8 of a purge system 1 of the combustion engine system 16. The gas connection line 8 connects the tank system 3 with a purge unit 6 of the purge system 1. The purge unit 6 comprises a purge pump 12 and a purge valve 14 that are arranged in line, wherein the purge valve 14 is arranged downstream the purge pump 12 with respect to a fluid flow direction through the purge system 1. The purge unit 6 may further comprise an optional, check valve 13 that is preferably arranged downstream the purge valve 14 of the purge system 1. A second line end 10 of a gas connection line 8 of the purge system 1 is connected with an induction line 4 of the combustion engine system 16. One end of the induction line 4 is connected with an air filter 19 for providing filtered air to the induction line 4. Another end of the induction line 4 is connected to a combustion engine 5 of the combustion engine system 16.

[0030] The purge unit 6 can just comprises a purge pump 12 and a check valve 13, wherein the check valve 13 can be arranged downstream the purge pump 12. According to a further exemplary embodiment, the purge unit 6 just comprises a purge valve 14 and check valve 13, wherein preferably, the check valve is located downstream the purge valve 14.

[0031] In FIG. 2, an exemplary embodiment of a purge system 1 according to the invention is schematically illustrated. The purge system 1 comprises a purge pump 12 for pumping CH-gas from a tank system 3 (c.f. FIG. 1) via a gas connection line 8, a purge valve 14 and an optional check valve 13 of the purge system 1 to a induction line 4 (c.f. FIG. 1) of the combustion engine system 16 (c.f. FIG. 1). For pumping the CH-gas, the purge system 1 comprises a motor. The purge system 1 further comprises a control unit 7 for operating the motor of the purge pump 12. According to this preferred embodiment, the purge system 1 further comprises a CH-sensor 11, a pressure sensor 15, a mass flow sensor 20 and a temperature sensor 21 are integrated with the purge pump 12. Alternatively, the CH-sensor 11 and/or the pressure sensor 15 and/or the mass flow sensor 20 and/or the temperature sensor 21 can be arranged somewhere at the gas connection line 8 and/or at the purge valve 14 and/or the optional check valve 13. In an alternative embodiment, the temperature sensor 21 can be integral with another sensor, e.g. the pressure sensor 15 or the mass flow sensor 20.

[0032] In FIG. 3, a method according to the invention is illustrated in a flow chart. In a first step 100, the CH-gas concentration of the fluid volume flow that flows from the first line end 9 towards the second line end 10 of the purge system 1 is measured by the CH-sensor 11. In a second step 200, the fluid volume flow that flows from the first line end 9 towards the second line end 10 is determined by the control unit 6, e.g. by measuring pressure by means of the pressure sensor 15 or by identifying a rotational speed of the purge pump 12. The fluid comprises air and CH-gas. In a third step 300, CH-gas volume flow is determined by the control unit from the measured CH-gas concentration and the determined fluid volume flow. Thus, an amount of CH-gas that is fed to the induction line 4 per time period is determined. In a fourth step 400, a fuel injection to the combustion engine 5 is adapted with respect to the determined CH-gas volume flow. This can be done by the control unit 7. This means, that the amount of CH-gas that is fed to the induction line 4 is reduced from the fuel feeding to the combustion engine 5. The higher the CH-gas volume flow into the induction line 4, the less fuel is injected to the combustion engine 5. Thus, a total amount of CH that is fed to the combustion engine 5 remains the same, independent from the amount of CH-gas fed to the induction line 4.

[0033] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.