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:
May. 24, 1994
Filed:
Sep. 25, 1992
Yuzuru Simazaki, Hitachi, JP;
Takao Kumasaka, Hitachi, JP;
Kunio Satoh, Hitachi, JP;
Youji Hirose, Mito, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Koki Co., Ltd., Tokyo, JP;
Abstract
An image recording apparatus including a photosensitive medium. A voltage is applied between the photosensitive medium and a developing sleeve of a developing unit, and a current flowing between the photosensitive medium and the developing sleeve is measured to be converted into a pulse waveform which is then compared by a predetermined reference value. On the basis of the result of the comparison, a gap is determined between the photosensitive medium and the developing unit, which is then advanced or retracted toward or from the photosensitive medium in accordance with the determined gap. Owing to the recording method carried out by the image recording apparatus, the gap can be selectively determined by observing the current waveform pattern of the current flowing between the photosensitive medium and the developing sleeve while decreasing gradually the gap therebetween, whereby a relation between the gap and height of a magnetic brush can definitely be established. Since the gap can be set within a range from a value representing an initial contact state in which the magnetic brush starts to contact with the photosensitive medium to a value representing a wholly contact state in which the whole magnetic brush contacts with the photosensitive medium with the aid of a current curve of the current flowing between the photosensitive medium and the developing sleeve, a contacting force of the magnetic brush bearing on the photosensitive medium can be weakened.