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:
Feb. 19, 2013
Filed:
Apr. 30, 2010
Hirotada Seki, Toyokawa, JP;
Akinori Kimata, Toyokawa, JP;
Satoru Sasaki, Toyokawa, JP;
Natsuyo Higashi, Toyokawa, JP;
Hiroaki Takatsu, Nishio, JP;
Hirotada Seki, Toyokawa, JP;
Akinori Kimata, Toyokawa, JP;
Satoru Sasaki, Toyokawa, JP;
Natsuyo Higashi, Toyokawa, JP;
Hiroaki Takatsu, Nishio, JP;
Konica Minolta Business Technologies, Inc., Tokyo, JP;
Abstract
In this toner concentration sensor, as the magnetic permeability of a two-component developercontaining toner and carrier in a two-component developing unithas changed with changing TC ratio of the two-component developer, the oscillation frequency of a first oscillation circuithaving a detection coilchanges, on the other hand the oscillation frequency of a second oscillation circuithaving a reference coildoes not change. While, changes in temperature conditions cause the oscillation frequency of the second oscillation circuit to change in the same way as the oscillation frequency of the first oscillation circuit. Therefore, utilizing a difference between the oscillation frequencies of the first and second oscillation circuits makes it possible to cancel out changes in the temperature conditions so that a value corresponding to only the magnetic permeability of the two-component developer can be obtained. Thus, detection errors of toner concentration due to temperature changes can be reliably prevented.