Patent Number: 
Section: claims

1. A regulator valve fault checking method for performing fault checking of a regulator valve regulating the flow of a fluid, comprising the steps of:periodically sampling a signal inputted into the regulator valve and, a degree of valve opening outputted from the regulator valve;calculating a speed of change of the sampled input signal;calculating a speed of change of the sampled degree of valve opening;calculating a weighting using the speed of change of the input signal and the speed of change of the degree of valve opening, and a weighting function that has been established in advance; andfault checking of the regulator valve using the sampled input signal, the sampled degree of valve opening and the calculated weighting,wherein the weighting function is a function where the weighting is large when the absolute values of the speed of change of the input signal and the speed of change of the valve opening are in ranges that are less than threshold values,wherein the step of performing the fault checking calculates a fault check indicator value, andwherein a specific time interval set in advance is used as a fault check evaluating interval, where the input signals and degrees of valve opening for which the weightings are calculated to be no less than a specific value are defined as valid data, and a fault check indicator value for use when performing fault checking of the regulator valve is calculated based on the input signals and degrees of valve opening that have been defined as valid data during the fault check evaluation time interval. 2. The regulator valve fault checking method as set forth in claim 1, wherein the input signal is an operating device pressure inputted into the regulator valve,wherein the step of performing the fault checking further comprises the steps of:calculating a fault check indicator value, used in fault checking of the regulator valve, from the sampled input signal and the sampled degree of valve opening, the calculated weighting, and a steady-state input/output relationship of the regulator valve when operating properly,calculating a center value between a maximum value and a minimum value for the operating device pressure for each individual degree-of-opening category, established in advance, from the operating device pressures and degrees of valve opening defined as valid data during the fault check evaluation time interval, andcalculating, as a fault check indicator value, a value indicating a difference between the center value of the operating device pressure in each degree-of-opening category and a steady-state input/output relationship, during proper operation, of the regulator valve. 3. The regulator valve fault checking method as set forth in claim 1, wherein the input signal is an operating device pressure that is inputted into the regulator valve,wherein the weighting function is a function wherein the weighting is large when the speed of change of the input signal and the speed of change of the valve opening are small, andwherein the step of performing the fault checking further comprises the steps of:calculating a difference between a maximum value and a minimum value for the operating device pressure for each individual degree-of-opening category, established in advance, from the operating device pressures and degrees of valve opening defined as valid data during the fault check evaluation time interval, andcalculating, as a fault check indicator value, a value indicating a difference between the maximum value and the minimum value of the operating device pressure in each degree-of-opening category. 4. A method to perform fault checking of a regulator valve regulating the flow of a fluid, comprising the steps of:periodically sampling, using a processor, a degree of valve opening of the regulator valve;calculating, using the processor, a rate of change of the sampled degree of valve opening;periodically sampling, using the processor, an input signal sent to the regulator valve;calculating, using the processor, a rate of change of the sampled input signal;retrieving, from a non-transitory memory, a predetermined weighting function;calculating a weighting, using the processor, based on the rate of change of the sampled degree of valve opening, the rate of change of the sampled input signal and the predetermined weighting function; andfault checking the regulator valve based on the sampled degree of valve opening of the regulator valve, the sampled input signal sent to the regulator valve, and the weighting. 5. The method of claim 4, wherein the fault checking step comprises the step of calculating a fault check indicator value based on the sampled input signal, the sampled degree of valve opening, the weighting, and a steady-state input/output relationship of the regulator valve when operating properly,wherein the steady-state input/output relationship is stored in the memory. 6. The method of claim 4, wherein the weighting function is large when the rate of change of the input signal and the rate of change of the valve opening are small. 7. The method of claim 4, wherein the calculating the weighting step further comprises the steps of:determining an absolute value of the rate of change of the input signal; anddetermining an absolute value of the rate of change of the valve opening;wherein the weighting function is large when the absolute values of the rate of change of the input signal and the rate of change of the valve opening are in ranges that are less than threshold values. 8. The method of claim 4, wherein the fault checking step comprises the steps of:setting, in advance, a specific time interval as a fault check evaluating interval;defining valid data as the input signals and degrees of valve opening used in the calculating the weightings step which are calculated to be no less than a specific value; andcalculating a fault check indicator value based on the valid data during the fault check evaluation time interval. 9. The method of claim 8, further comprising the step of setting the input signal as an operating device pressure inputted into the regulator valve;wherein the fault checking step comprises the steps of:establishing in advance, a plurality of individual degree-of-opening categories;calculating a center value between a maximum value of the operating device pressure and a minimum value of the operating device pressure for each individual degree-of-opening category based on the operating device pressures and degrees of valve opening defined as valid data during the fault check evaluation time interval; andcalculating a fault check indicator value indicating a difference between the center value in each degree-of-opening category and a steady-state input/output relationship of the regulator valve during proper operation. 10. The method of claim 8, further comprising the step of setting the input signal as an operating device pressure inputted into the regulator valve;wherein the fault checking step comprises the steps of:establishing in advance, a plurality of individual degree-of-opening categories;calculating a difference between a maximum value of the operating device pressure and a minimum value of the operating device pressure for each individual degree-of-opening category based on the operating device pressures and degrees of valve opening defined as valid data during the fault check evaluation time interval; andcalculating a fault check indicator value indicating a difference between the maximum value and the minimum value for the operating device pressure for each individual degree-of-opening category.