×

Method and apparatus for image forming capable of effectively performing a charging process

  • US 7,630,659 B2
  • Filed: 05/09/2006
  • Issued: 12/08/2009
  • Est. Priority Date: 05/09/2005
  • Status: Active Grant
First Claim
Patent Images

1. An image forming apparatus, comprising:

  • a charge carrier configured to carry a charge;

    an AC voltage calculator configured to calculate a value of an alternating-current voltage of an application voltage based on first and second alternating-current voltages, first and second alternating currents, and a predefined reference alternating current capable of evenly charging a surface of the charge carrier;

    a charging device configured to charge the surface of the charge carrier, the charging device comprising;

    a charge-applying device arranged parallel to and facing the charge carrier,a power controller configured to apply to the charge carrier the application voltage including a direct-current voltage and the alternating-current voltage superimposed onto the direct-current voltage,an alternating-current detector configured to detect an alternating current flowing through the charge carrier when the charge-applying device applies the application voltage to the charge carrier, anda voltage value controller configured to determine the value of the alternating-current voltage of the application voltage based on at least two alternating currents detected by the alternating-current detector; and

    an instructing mechanism configured to generate an instruction, whereinthe voltage value controller is configured to determine the alternating-current voltage value of the application voltage in accordance with the instruction generated by the instructing mechanism,the at least two alternating currents include the first and second alternating currents detected when the power controller applies the first and second alternating-current voltages, respectively, of the application voltage to the charge-applying device, andthe first and second alternating-current voltages are different from each other and each have a value at least double a discharge-start voltage that initiates an electrical discharge from the charge-applying device to the charge carrier.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×