Canon Kabushiki Kaisha

Midori Yasuda

Masashi Kamada

Tomohiro Suzuki

Ryo Kobayashi

Yuki Igarashi

Ryoya Shinjo

Masato Eiyama

Masashi Negishi

Yuki Kamio

Takeshi Ono

Noriyuki Suzuki

Akira Ito

Shinji Takagi

Masafumi Wataya

Kazuhiko Morimura

Masaaki Okada

Takayuki Ninomiya

Sohei Tanaka

Hiroyuki Hyotani

A roll sheet, in which a continuous sheet is wound in a roll form, is caused to rotate in a forward direction to supply the sheet to a printing unit. First and second sensors are arranged at positions facing an outer circumferential surface of the roll sheet and deviated in an axis line direction of the roll sheet. Outputs of the first and second sensors are changed in accordance with a distance to a sheet of the roll sheet. A rotation direction of the roll sheet is switched from a forward direction to a reverse direction on the basis of the outputs of the first and second sensors while the roll sheet is being rotated in the reverse direction.

Printing apparatus

An ejection apparatus includes an ejection head having an ejection port, a droplet detection unit, an acquisition unit, a control unit, and a decision unit. The droplet detection unit detects that a droplet ejected from the ejection port has reached a predetermined position. The acquisition unit acquires information regarding a velocity of movement of the detected droplet. The control unit controls the ejection head to eject the droplet from the ejection port. The decision unit decides a number of consecutive ejections of a plurality of droplets from the ejection head based on the acquired information regarding the velocities of each of the plurality of droplets ejected consecutively and detected by the droplet detection unit. If the acquisition unit acquires the information regarding velocities of detected droplets, the control unit controls the ejection head to consecutively eject the droplets from the ejection head based on the decided number of consecutive ejections.

Ejection apparatus and ejection control method

An ink-jet printing head and an ink-jet printing apparatus can reduce fluctuation of density of an ink ejected from each nozzle by ejecting ink of different densities from the same nozzle without varying size of an ink droplet, or by controlling ejection of a mixture ink, in which a plurality of inks are mixed, for forming an image. The ink-jet printing head includes a plurality of ejection openings for ejecting ink, a plurality of ink passages communicated with the plurality of ejection openings, ink ejecting energy generating elements provided in the plurality of ink passages, a mixing liquid chamber connected to the plurality of ink passages in common, a plurality of individual liquid chambers supplying ink to the mixing liquid chamber, and a valve mechanism provided between the individual liquid chamber and the mixing liquid chamber and controlling supply amount of the inks supplied from the individual liquid chambers.

Ink-jet printing head and ink-jet printing apparatus

This invention provides an ink jet printing apparatus and method with an inexpensive arrangement that allows a stable supply of an appropriate voltage to heaters without requiring varying load resistance or changing a power supply voltage. The ink jet printing apparatus of this invention has a plurality of nozzles arrayed in a print head; a plurality of energy generators installed one in each of the nozzles for generating an ejection energy to eject ink from the nozzles, the plurality of energy generators being divided into a plurality of blocks; and a drive controller f or simultaneously driving the energy generators in each block. The drive controller supplies an energy to the energy generators making up each block through different kinds of energy supply paths.

Ink jet printing apparatus and ink jet printing method

A bus arbiter capable of avoiding needless increase in circuit scale is provided. The bus arbiter controls a bus shared by a CPU (central processing unit) and a plurality of apparatuses for generating addresses. The bus arbiter includes a determination unit for determining if a request of an address is a request of an address where no corresponding device is present, and a processor for passing the request by transmitting an ACK signal without performing a writing operation for a request of a writing operation, and transmitting dummy data and an ACK signal without performing a reading operation for a request of a reading operation, when the determination unit has determined that the request is a request of an address where no corresponding device is present.

Bus arbiter

Bus arbiter operable as a DRAM controller

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Yokohama, Japan

Midori Yasuda