The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 02, 1990
Filed:
May. 31, 1988
Toshihiko Yamaoki, Osaka, JP;
Kenichiro Wakisaka, Hirakata, JP;
Kouji Minami, Higashiosaka, JP;
Masayuki Iwamoto, Itami, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
An electrostatic recording apparatus includes a photosensitive drum which is charged at +700 V by a first charger. Intensity of the light emitted from an LED array that is downstream from the first charger is adjusted such that a light image having strong intensity and/or a light image having weak intensity can be irradiated to the photosensitive drum. A surface voltage of a portion where the light image having weak intensity is irradiated becomes +400 V. A surface voltage of a portion where the light image having strong intensity is irradiated becomes +100 V. The photosensitive drum is charged at -400 V in the reverse polarity opposite to that of the first charger by a second charger which is arranged downstream from the LED array. As a result, electrostatic latent images of three gradations having voltages of +300 V, 0 V and -300 V respectively are formed on the photosensitive drum. The electrostatic latent images of +300 V and -300 V are respectively developed by developers with a black toner being charged in the negative polarity (-) a red toner being charged in the positive polarity (+).