Minolta Camera Kabushiki Kaisha

Yuji Hayashi

Susumu Sakakibara

Yamato Kitajima

Katsumi Maeda

A developing device including a rotatable developing sleeve confronting an electrostatic latent image support member, a supply device for supplying developer to a peripheral surface of the developing sleeve, a bristle height regulating member, a device for removing from the peripheral surface of the developing sleeve, the developer having passed through a developing region, a cutoff device for cutting off supply of the developer from the supply device to the developing sleeve, which is retractably projected into a developer supply region defined between the developing sleeve and the supply device and a magnet member provided fixedly in the developing sleeve and having a developing magnetic pole confronting the support member, a first magnetic pole confronting the bristle height regulating member and a second magnetic pole of a polarity identical with that of the first magnetic pole such that the developer is continuously held in an erect state on the developing sleeve by the first and second magnetic poles.

Developing device with retractable cutoff member

A density measuring device for originals in an enlarging/reducing projector, which is installed in a electrophotographic copying machine or in an image sensor to measure original densities for enlarged/reduced printing under automatic exposure control. The device includes a light sensor, which receives light from an original via mirrors, and moves to keep a constant distance between the sensor and the original when the mirrors move in response to the change of projective magnification. The length of optical path for original density measurement is corrected by moving the sensor separately from but in accordance with the projection lens as the lens moves to change projective magnification.

Growing community of inventors

Osaka, Japan

Yuji Hayashi