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:
Mar. 10, 1992
Filed:
Jan. 25, 1989
Isamu Terashima, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A developing apparatus operates to develop an electrostatic latent image by using developer which is a mixture of carrier particles and toner particles. Upon detecting a fall in the toner concentration in the developer, a toner supply device supplies stored toner particles to the developer. The supplied toner particles are mixed, by stirring, with the developer by a stirring device. The toner supply device includes a supply roller covered by a short texture or a porous elastic material having a predetermined high resistivity in contact with a circulation current of developer, and a bias power source which applies a bias voltage between the supply roller and the circulation current of developer such that the supply roller and the supplied toner particles have the same voltage polarity.