Patent ID: 7577388
Filing Date: 2009-08-18
Classification: G03G

Abstract:
1. A developing roller comprising: (I) a developing sleeve that is made of nonmagnetic material, and that holds and conveys a developer containing a toner and a magnetic carrier; and (II) a magnetic member that is fixed inside the developing sleeve, wherein the magnetic member comprises: (i) a development magnetic pole that corresponds to a development area where the developer is applied; (ii) a before-development magnetic pole that is provided at an upstream side of the developer-conveying direction with respect to the development magnetic pole, and that has a polarity different from the development magnetic pole; and (iii) an after-development magnetic pole that is provided at a downstream side of the developer-conveying direction with respect to the development magnetic pole, and that has a polarity different from the development magnetic pole, wherein θ wherein θ θ θ