Method of determining a resistive current
AssigneeXerox Corporation
InventorJerry F. Adams
Life of this patent
Estimating the term…
Abstract
A xerographic charging device corona current is determined by forming a first signal across a sense resistor in series with the charging device power supply, forming a second signal using a resistive voltage divider network across the power supply, and forming a third signal using a resistor-capacitor charging circuit across the power supply, and then processing the first, second and third signals to form an output signal that is based on the corona current.
Claims35
A method of determining a resistive current of a load, the load further comprising a capacitive current, the load driven by an input signal, the input signal being sinusoidal, the method comprising:
- (a) forming a first signal substantially in-phase with and proportional to the sum of the resistive current and the capacitive current;
- (b) forming a second signal in-phase with the input signal;
- (c) forming a third signal opposite in phase to the capacitive current;
- and
- (d) processing the first, second and third signals to form a first result based on the resistive current.
A method of determining a resistive current of a load, the load further comprising a capacitive current, the load driven by an input signal, the method comprising:
- (a) forming a first signal in-phase with and proportional to the sum at all frequencies comprised in the input signal of the resistive current and the capacitive current;
- (b) forming a second signal in-phase with the input signal;
- (c) forming a third signal proportional to the capacitive current at all frequencies comprised in the input signal;
- and
- (d) processing the first, second and third signals to form a first result based on the resistive current.
A method of determining a resistive current of a load, the load comprising a capacitive current, the load driven by an input signal, the input signal being sinusoidal, the method comprising:
- (a) forming a first signal in-phase with and proportional to the sum of the resistive current and the capacitive current;
- (b) forming a second signal in-phase with the input signal;
- (c) forming a third signal opposite in phase to the capacitive current;
- and
- (d) processing the first, second and third signals to form a first result based on the resistive current, wherein:
- the first signal is based on a sense resistor in series with the input signal;
- the second signal is based on a difference between the first signal and a first ratio signal, the first ratio signal being formed by a resistive divider network coupled between the input signal and the first signal;
- and
- the third signal is based on a difference between the first signal and a second ratio signal, the second ratio signal being formed by a resistor-capacitor divider network coupled between the input signal and the first signal, and wherein:
- the resistance of the sense resistor is much less than the load resistance;
- the resistive divider network comprises a first resistor and a series-connected second resistor and the resistance sum of the first resistor and the second resistor is much greater than the load resistance;
- and
- the resistor-capacitor divider network comprises a third resistor and a series-connected capacitor and the resistance of the third resistor is much greater than the load resistance.
Dependencies are inferred from the claim text.