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. 01, 2022
Filed:
Jul. 29, 2020
Canon Kabushiki Kaisha, Tokyo, JP;
Tomoyuki Sakamaki, Tokyo, JP;
Yuta Okuyama, Matsudo, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
An image forming apparatus includes an image bearing member, an exposure device configured to expose the image bearing member to form an electrostatic latent image thereon, and a developing device including a rotatable developing member configured to carry and feed a developer containing toner and a carrier to develop the electrostatic latent image formed on the image bearing member, and a magnet provided non-rotatably and stationarily inside the rotatable developing member including a developing magnetic pole, wherein magnetic chains formed by the carrier, on the rotatable developing member, magnetized by the magnet contact the electrostatic latent image formed on the image bearing member in a developing region of the rotatable developing member, wherein a maximum peak position where a magnetic flux density of the developing magnetic pole is maximum with respect to a normal direction of the rotatable developing member exists within a range of the developing region with respect to a rotational direction of the rotatable developing member, and wherein a ratio of an 80%-value-width which is a width of a portion where the magnetic flux density of the developing magnetic pole with respect to the normal direction of the rotatable developing member is 80% of the maximum of the magnetic flux density of the developing magnetic pole with respect to the normal direction of the rotatable developing member to a half peak width which is a width of a portion where the magnetic flux density of the developing magnetic pole with respect to the normal direction of the rotatable developing member is half of the maximum of the magnetic flux density of the developing magnetic pole with respect to the normal direction of the rotatable developing member is 0.65 or more.