Method and device for activating a valve of a fuel vapor retention system
View Patent ↗For the purposes of a determination of a fuel vapor loading level of a fuel vapor retention system of a combustion engine, an opening level of a valve of the fuel vapor retention system is increased in steps or continuously during a determination phase. Furthermore, the valve is activated at most a predefined first period prior to a start of the determination phase by a conditioning pulse at least whenever the valve was closed previously for a second period that is longer than a predefined threshold value. The conditioning pulse is generated in such a way that the valve definitely opens at most for a predefined opening period and then closes again.
1. A method for activating a valve of a fuel vapor retention system of a combustion engine to determine a fuel vapor loading level of the fuel vapor retention system, comprising:
activating the valve for a predefined first period prior to a start of a determination phase by a conditioning pulse at least whenever the valve had been closed for a second period that is longer than a predefined threshold value, the conditioning pulse is generated such that the valve opens for a predefined opening period and then closes; and
increasing an opening level of the valve during the determination phase.
2. The method as claimed in claim 1 , wherein the valve is activated at most for the predefined first period prior to the start of the determination phase.
3. The method as claimed in claim 1 , wherein the opening level of the valve is increased in steps or continuously during the determination phase.
4. The method as claimed in claim 3 , wherein the predefined opening period is at most 100 milliseconds.
5. The method as claimed in claim 4 , wherein a duration of the predefined first period is approximately between 0.5 and 15 seconds.
6. The method as claimed in claim 5 , wherein the duration of the predefined first period is between 0.5 and 15 seconds.
7. The method as claimed in claim 6 , wherein the predefined threshold value is at least 30 seconds.
8. A device for activating a valve of a fuel vapor retention system of a combustion engine configured to determine a fuel vapor loading level of the fuel vapor retention system:
an actuator for increasing an opening level of the valve during a determination phase;
an activation device for activating the valve by a conditioning pulse for a predefined first period prior to a start of the determination phase at least whenever the valve is closed previously for a second period greater than a predefined threshold value; and
a generating device that generates the conditioning pulse such that the valve opens at most for a predefined opening period and then closes.
9. The device as claimed in claim 8 , wherein the valve is activated at most for the predefined first period prior to the start of the determination phase.
10. The device as claimed in claim 8 , wherein the opening level of the valve is increased in steps or continuously during the determination phase.
11. The device as claimed in claim 9 , wherein the predefined opening period is at most 100 milliseconds.
12. The device as claimed in claim 11 , wherein a duration of the predefined first period is approximately between 0.5 and 15 seconds.
13. The device as claimed in claim 12 , wherein the duration of the predefined first period is between 0.5 and 15 seconds.
14. The device as claimed in claim 13 , wherein the predefined threshold value is at least 30 seconds.