Toshiba Tec Kabushiki Kaisha

Riso Technologies Corporation

Taiki Goto

Kazuhiro Hara

Masashi Shimosato

Noboru Nitta

Kazuhiko Ohtsu

Yoshiaki Kaneko

Akio Hamada

According to an embodiment, a liquid dispensing head includes a nozzle plate with a plurality of nozzles and a plurality of pressure chambers respectively communicating with the nozzles. A vibration plate is on a side of the pressure chambers opposite the nozzle plate. A supply-side flow path for liquid to be dispensed from the nozzle is on an inlet side of the plurality of pressure chambers. A discharge-side flow path for the liquid is on an outlet side of the pressure chambers. Piezoelectric elements are positioned to vibrate the vibration plate to change a volume of the pressure chambers for ejecting (dispensing) the liquid from the plurality of nozzles. The supply-side flow path is set to have a flow path resistance that is the same as a flow path resistance of the discharge-side flow-path.

Liquid dispensing head

According to one embodiment, a liquid discharge head includes a flexible printed circuit (FPC) connected to piezoelectric elements. The FPC has a first end in the first direction. A wiring layer of the FPC has a first region at the first end and a cover layer covering on a second region. The piezoelectric elements are spaced from each other in a second direction and each has a first electrode on a side surface facing towards the FPC. The first side has a joint surface facing the first region of the wiring layer. The first electrode is electrically connected to the wiring layer at the joint surface. The side surface includes a step portion that is recessed from the joint surface. A portion of the cover layer protrudes into a space adjacent to the step portion.

Liquid discharge head

A liquid circulation device includes a liquid chamber that stores a liquid that is to be supplied to a liquid discharge head. A pipeline through which the liquid can be circulated between the liquid chamber and the liquid discharge head is provided. A heater heats the liquid circulating in the pipeline. A first temperature sensor measures the temperature of the heater, and a second temperature sensor measures the temperature of the liquid in the pipeline. A controller controls the heating of the heater based on the liquid temperature measured by the second temperature sensor. The controller also monitors a change in the measured temperature of the heater over time and turns off the heating of the heater when the monitored change satisfies a predetermined stop condition.

Liquid circulation device and liquid discharge apparatus

According to an embodiment, a piezoelectric pump includes a pressure chamber and a buffer chamber. The buffer chamber is provided for at least one of an inlet of the pressure chamber in which liquid flows or an outlet of the pressure chamber from which the liquid is discharged. The buffer chamber includes a wall portion that forms a gas chamber that retains gas from the liquid.

Piezoelectric pump and liquid ejection device

According to one embodiment, a fluid circulation apparatus includes a first tank to store fluid to be supplied to a fluid ejection head, a circulation path including a first flow path portion to provide fluid from the first tank to a supply port of the fluid ejection head, and a second flow path portion to return fluid from a collection port of the fluid ejection head to the first tank, a bypass flow path to connect the supply port to the collection port outside of the fluid ejection head, and a pressure sensor configured to measure pressure of the bypass flow path.

Fluid circulation apparatus and fluid ejection apparatus

According to an embodiment, a piezoelectric pump includes a pressure chamber. A groove is provided to a bottom portion of the pressure chamber. The groove includes an inlet and an outlet on a bottom portion of the groove, liquid being caused to flow in the pressure chamber through the inlet and to be discharged from the pressure chamber through the outlet.

According to one embodiment, a fluid circulation apparatus includes a first tank to store fluid to be supplied to a fluid ejection head, a circulation path including a first flow path portion to provide fluid from the first tank to a supply port of the fluid ejection head, and a second flow path portion to return fluid from a collection port of the fluid ejection head to the first tank, a bypass flow path that connects the supply port to the collection port outside of the fluid ejection head, and a buffer tank in the bypass flow path.

A liquid circulation device comprises a booster pump that draws liquid from a liquid replenishing tank to supply it to a liquid discharge head; a pressure reducing pump that collects the liquid from the liquid discharge head to supply it to the liquid replenishing tank; a buffer tank connected between the liquid discharge head and the booster pump and between the liquid discharge head and the pressure reducing pump, and into which the liquid flows; a pressure sensor that detects pressure in the buffer tank; and a processor that controls driving voltages of the booster pump and the pressure reducing pump based on a nozzle surface pressure of the liquid discharge head calculated based on pressure data detected by the pressure sensor, and determines whether the liquid is deficient based on the nozzle surface pressure, the driving voltages of the booster pump and the pressure reducing pump.

Liquid circulation device and liquid discharge device

An ink circulation device for an ink jet head includes a first ink storage unit that stores ink to be supplied to an ink jet head, a second ink storage unit that stores ink to be returned from the ink jet head, a pump that operates according to an electric signal to transport the ink from the second ink storage unit to the first ink storage unit, a filter between the pump and the first ink storage unit, a first pressure sensor configured to detect an internal pressure of the first ink storage unit, a second pressure sensor configured to detect an internal pressure between the pump and the filter, and a drive circuit configured to generate the electric signal according to a pressure difference between the internal pressure detected by the second pressure sensor and the internal pressure detected by the first pressure sensor.

Growing community of inventors

Mishima Shizuoka, Japan

Taiki Goto