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. 11, 2005
Filed:
Jan. 29, 2004
Hisao Okada, Ibaraki, JP;
Masayoshi Nakayama, Ibaraki, JP;
Hisao Okada, Ibaraki, JP;
Masayoshi Nakayama, Ibaraki, JP;
Ricoh Printing Systems, Ltd., Tokyo, JP;
Abstract
The invention provides an electronic photographing apparatus using a two-component developer as a mixture of a toner and a carrier as well as a development unit including a developer roll having magnetic poles therein. The electronic photographing apparatus includes a development bias power source for applying to the developer roll a development bias voltage where an AC voltage is superimposed on a DC voltage. The electronic photographing apparatus develops a latent image on a photosensitive body by using toner to form an image, characterized in that the ratio of the volume of the carrier to a space sandwiched between the developer roll and the photosensitive body is set within a range from 32 percent to 46 percent and that that the resistivity of the carrier under a field strength of 2000 V/cm is set to 3×10Ωcm or more.