Sharp Kabushiki Kaisha Corporation

Yasushi Nakanishi

Akihiko Taniguchi

Takahiro Fukunaga

Masakiyo Okuda

Manabu Matsumoto

Atsushi Narukawa

Haruyoshi Migita

Itsuro Kato

Masanori Mori

Yukio Nakai

A portable copying apparatus of the type in which a document table is movably disposed thereon is generally provided with a lock member for locking the document table and a system for controlling movement of the document table. The lock member is disposed on one side of the apparatus perpendicular to the direction of movement of the document table. The control system contains a plurality of timers so that the document table may move in a direction in which the document table is released from the lock member and further move to its start position.

System for controlling movement of a document table in a copying

An automatic exposure control device for use in a copying machine in which a light source for illuminating the light to an original document is controlled based on the signal representing the light amount of the original document sensed by a light senses. There are two kinds of HIGH level limiter for limiting the upper limit of the power supplied to the light source. The HIGH level limiters are selected depending on whether the amount of light of the light source has been raised sufficiently or not, whereby over exposure copy or foggy copy can be prevented.

Automatic exposure device

An image forming apparatus with a main body composed of a light source, a photoreceptor, charging device for electrostatically a charging the surface of the photoreceptor, a developing device for supplying toner particles to the surface of the photoreceptor a transferring charger for transferring a toner image formed on the surface of the photoreceptor onto a copying sheet, and a high-voltage source for applying a high voltage trigger to both said charging device and the transferring charger simultaneously. The apparatus is designed to execute original scanning as an original glass plate is moved with respect to the main body, characterized in containing a reflecting unit for reflecting the light from the light source to illuminate the surface of the photoreceptor at an area between the charging device and the developing device, the reflecting unit is disposed at a position corresponding to the trailing end of the original glass plate in its forward movement for original scanning. The apparatus is designed to eliminate the need of providing an independent light source for blank exposure thereby simplifying the arrangement for blank exposure to be performed with respect to the photoreceptor and saving the manufacturing cost for the apparatus.

Image forming apparatus with a common power source for various chargers

A copying timing counting system for counting the rotation angle of a photoreceptor drum in an electrophotographic copying machine comprises a pulse generator, and a pulse counter. The pulse counter is responsive to the pulse generator for counting both the pulse rising edge and the pulse falling edge. Since the counter can count both the pulse rising edge and the pulse falling edge, the resolving power of the photoreceptor drum can be doubled as compared with the detection system of either of the pulse rising edge or the pulse falling edge taken alone.

Copying process timing control system for electrophotographic copying

An electrophotographic copying machine includes a control circuit, a combined display responsive to the control circuit for showing the number of one or more copied papers, and the position of any paper jam or the operation condition. The combined display utilizes figure segments illuminated to form any figure, silhouette segments of the figure segments illuminated to provide a silhouette of the copying machine, and position marks illuminated to indicate the position of trouble in the machine and its operation conditions.

Combined alarm display and numerical display for electrophotographic

A control system for an electrophotographic copier includes a detector switch for outputting a warning signal when it detects that a container for discarded toner for the copier becomes full and a device for stopping the copying operation only after a specified number of copies are produced after the container became full and the aforementioned warning signal has been outputted.

Growing community of inventors

Yamatokoriyama, Japan

Yasushi Nakanishi