Screen Holdings Co., Ltd.

Ricoh Company, Ltd.

Dainippon Screen Mfg. Co., Ltd.

Motoyuki Anno

Mitsuru Tanemoto

Shinsuke Yamashita

Tomonori Tamura

Mitsuru Satoh

Hiroyuki Fuchioka

Kazutaka Tasaka

Jindra Vosahlo

An inkjet printing apparatus includes a first and second tanks, and a printer section including an inkjet head which ejects ink droplets toward a printing medium. The inkjet printing apparatus includes a first supply system which supplies ink from the first tank to the second tank, a second supply system which includes an ink supply pump and supplies ink from the second tank to the printer section, and a remaining amount detection unit which detects the amount of ink remaining in the first tank. The remaining amount detection unit calculates the amount of ink transferred from the first tank to the second tank in a measurement period during which ink is supplied from the first tank to the second tank, based on an increase in the amount of the ink stored in the second tank in the measurement period and the operation state of the pump in the measurement period.

Inkjet printing device and ink remaining quantity detection method in inkjet printing device

An inkjet printing apparatus is selectively composed of a plurality of transportation units, i.e., an inlet unit, a first intermediate unit, a second intermediate unit, and an outlet unit, having a transport path with slopes in side view of a transportation direction from a paper feeder to a take-up roller. When the transportation units are connected, a connecting part of the transportation unit is an inclination change point VP of the transport path. This achieves maintained tension to the print medium. As above, the inkjet printing apparatus may be selectively composed of a plurality of transportation units. Accordingly, the inkjet printing apparatus is constructible by combination of the units for various type productions, leading to a suppressed stock.

Printing apparatus

Ink in an ink tank is fed through a dissolved gas control filter to a printer head. A gas pressure changing mechanism reduces pressure in a gas pressure control tank. In response, the dissolved gas control filter removes gas dissolved in the ink. The gas pressure control tank is placed under pressure corresponding to a sum of the pressure reduced by the gas pressure changing mechanism and the pressure of the gas having been removed from the liquid. A gas pressure measuring part measures the sum of these pressures as pressure in the gas pressure control tank. Then, a controller determines when time of exchange of the dissolved gas control filter has come based on the magnitude of a gradient of gas pressure variation in the gas pressure control tank.

Liquid feeding device and method of determining time of exchange of gas control element

A liquid cartridge includes an ink bag for storing liquid and being capable of changing its shape, a housing for storing the ink bag, a guiding tube member for being placed in the ink bag, and a liquid supply outlet for providing the liquid to outside the ink bag and being connected to an end of the guiding tube member. Another end of the guiding tube member is placed close to or touching a bottom of the ink bag. The liquid cartridge further includes a bottom plate for supporting the bottom of the ink bag. The bottom plate is configured to be moved with respect to the housing. As remaining ink in the ink bag decreases, the bottom plate is moved to be in an inclining state by an inclination adding member that is placed in a cartridge installing unit of an apparatus.

Liquid container and image forming apparatus

A head unit has a supply tank provided above a plurality of heads, for storing ink and a collecting part having an internal space into which ink flows from the plurality of heads. In the head unit, a plurality of ink inlet pipes serving as a plurality of passages leading from the supply tank to the plurality of heads have the same shape and the same resistance and a plurality of ink outlet pipes serving as a plurality of passages from the plurality of heads to the collecting part have the same shape and the same resistance. This equalizes respective flow rates of ink and respective pressures of ink at nozzles in the plurality of heads. As a result, it is possible to suppress variation in landing positions and the like of ink with respect to the nozzles among the plurality of heads.

Growing community of inventors

Kyoto, Japan

Motoyuki Anno