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:
Dec. 19, 2000
Filed:
Dec. 04, 1998
Shinichi Namekata, Yokohama, JP;
Yuji Sawai, Yokohama, JP;
Toshiaki Motohashi, Souka, JP;
Katsuya Kawagoe, Kamakura, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
In an electrostatic image forming apparatus, including a corona discharger located so as to face an image carrier on which a toner image is to be formed. When a paper or similar recording medium is brought between the image carrier and the discharger, the discharger effects corona discharge at the rear of the recording medium so as to charge the medium to a polarity opposite to the polarity of the toner image. The toner image is then transferred from the image carrier to the recording medium. A polarity switcher allows a voltage of substantially the same polarity as the toner to be applied to a discharge wire included in the discharger, and environmental sensing device allows this voltage to be changed based on temperature and humidity conditions. The apparatus is free from defective discharge and defective image transfer ascribable to the deposition of free or isolated toner on the discharger.