Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
159 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; keeping the check valve closed to maintain an overpressure in the tank in a predetermined interval during running of the internal combustion engine when no indication is present that the tank may be opened; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper thereshold valve and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed.
Claim 2
Independent Claim
159 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; keeping the check valve closed to maintain an overpressure in the tank in a predetermined interval during running of the internal combustion engine when no indication is present that the tank may be opened; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper thereshold valve and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed.
Claim 3
Dependent Claim
70 words
The method of claim 1, further comprising: checking whether the tank closure is being opened or is being closed to obtain an indication as to an opening/closure operation; and, then performing one of the following steps: controlling the check valve to open when the check shows that the tank closure is being opened; or, controlling the check valve to close when the check shows that the tank closure is closed.
Claim 4
Independent Claim
181 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and a check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper threshold value and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed; the operation of the engine being used as an indication for the opening/closing operation of the tank and the method including the further steps of: opening the check valve when the engine is switched off; and, after a pregiven time span has elapsed after the opening of the check valve, again closing the check valve.
Claim 5
Independent Claim
181 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and a check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper threshold value and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed; the operation of the engine being used as an indication for the opening/closing operation of the tank and the method including the further steps of: opening the check valve when the engine is switched off; and, after a pregiven time span has elapsed after the opening of the check valve, again closing the check valve.
Claim 6
Dependent Claim
52 words
The method of claim 1, wherein the level of the threshold values for the pressure difference is dependent upon values of operating parameters and the level of said threshold values is reduced with such values of the operating parameters which point to an opening of the tank closure which may occur soon.
Claim 7
Independent Claim
147 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and a check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper threshold value and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed; checking as to whether said tank-venting arrangement is tight; and, controlling the check valve to open if a leak is determined.
Claim 8
Independent Claim
147 words
A method for operating a tank-venting arrangement on a motor vehicle having an engine, the tank-venting arrangement including a tank having a tank closure, an adsorption filter and a check valve interconnecting the tank and the adsorption filter, the method comprising the steps of: measuring the pressure difference between the pressure in the tank and the ambient pressure at least when the engine is running; opening the check valve when one of the following occurs: the pressure difference increases beyond an upper threshold value and an indication is present that the tank may be opened; and, closing the check valve when one of the following occurs: the pressure difference drops below a lower threshold value and an indication is present that the tank may be closed; checking as to whether said tank-venting arrangement is tight; and, controlling the check valve to open if a leak is determined.
Claim 9
Dependent Claim
215 words
A tank-venting arrangement comprising: a tank having a tank closure; an adsorption filter; an electrically drivable check valve interconnecting said tank and said adsorption filter; a difference pressure sensor for measuring the pressure difference between the pressure in said tank and the ambient and emitting a pressure difference signal indicative of said pressure difference; comparator means for comparing said pressure difference signal to an upper and a lower threshold value and for supplying an opening signal to said check valve for opening said check valve when said pressure difference signal is greater than said upper threshold value and for supplying a closing signal to said check valve for closing said check valve when said pressure difference signal drops below said lower threshold value thereby maintaining a predetermined overpressure relative to atmospheric pressure in said tank independently of the pressure in said adsorption filter during operation of the vehicle and while no opening of said tank closure is expected; and, detector means for making a determination of a possible opening of the tank and supplying an opening signal to said check valve when said determination is made and for making a determination of a possible closing of the tank and supplying a closure signal to said check valve when said determination of possible closing is made.
Claim 10
Dependent Claim
215 words
A tank-venting arrangement comprising: a tank having a tank closure; an adsorption filter; an electrically drivable check valve interconnecting said tank and said adsorption filter; a difference pressure sensor for measuring the pressure difference between the pressure in said tank and the ambient and emitting a pressure difference signal indicative of said pressure difference; comparator means for comparing said pressure difference signal to an upper and a lower threshold value and for supplying an opening signal to said check valve for opening said check valve when said pressure difference signal is greater than said upper threshold value and for supplying a closing signal to said check valve for closing said check valve when said pressure difference signal drops below said lower threshold value thereby maintaining a predetermined overpressure relative to atmospheric pressure in said tank independently of the pressure in said adsorption filter during operation of the vehicle and while no opening of said tank closure is expected; and, detector means for making a determination of a possible opening of the tank and supplying an opening signal to said check valve when said determination is made and for making a determination of a possible closing of the tank and supplying a closure signal to said check valve when said determination of possible closing is made.
Claim 11
Dependent Claim
39 words
The tank-venting arrangement of claim 6, further comprising a tank closure sensor for emitting a tank opening signal when the tank closure is opened; and, a switching unit for opening said check valve in response to said opening signal.
Claim 12
Dependent Claim
19 words
The tank-venting arrangement of claim 6, said check valve being a valve which is closed in the non-driven condition.