Toshiba Tec Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Hideyuki Akaba

Hideaki Nishida

Kazuhisa Kimura

Hidekazu Ishii

Noboru Nitta

An image forming apparatus includes an ink jet head, having a pressure chamber, a flow path and a nozzle, which ejects ink in the pressure chamber through the nozzle, a first tank connected to the flow path, a supply unit which supplies ink in the first tank to the pressure chamber through the flow path, a second tank connected to the flow path, a discharge unit which moves ink in the pressure chamber to the second tank through the flow path, and a control section which activates the supply unit and the discharge unit so that ink in the pressure chamber is discharged to the second tank by the discharge unit, ink in the first tank is charged to the pressure chamber by the supply unit and the liquid surface of ink supplied to the pressure chamber is projected from the nozzle.

Image forming apparatus having ink jet head and method for performing maintenance of the same

According to one embodiment, an inkjet device includes: an ink circulating device configured to communicate with an inkjet head to form an ink circulating system; an arithmetic unit configured to calculate, on the basis of pressure detected from the ink circulating system, pressure in an ink discharge port section according to an arithmetic expression set in advance; a pressure determining unit configured to determine, with proper nozzle pressure in the ink discharge port not discharging ink set as a reference value, whether a value calculated by the arithmetic unit is positive pressure or negative pressure with respect to the reference value; and a negative pressure regulator configured to communicate with the ink circulating system and perform, if the pressure determining unit determines that the value is the positive pressure, an ink reducing operation in the ink circulating system and increase a negative pressure value on the ink discharge port. The pressure determining unit changes the reference value to a negative pressure side.

Inkjet head device and method of controlling inkjet head

In such a manner that ink in each of a plurality of pressure chambers for holding the ink therein is brought to a positive pressure state of being ejected from respective nozzles respectively communicating with the respective chambers to the outside of each of the pressure chambers, a cleaning member abutted against a nozzle plate formed with a plurality of nozzles is moved along the nozzles in a state in which pressure is applied to all of the pressure chambers, to thereby extrude foreign particles outside the pressure chambers by the ink ejected from the respective nozzles to the outside of the pressure chambers, thereby making it possible to recover the ink, whereby the occurrence of a delivery failure due to the foreign particles around the nozzles being absorbed into the pressure chambers, can be prevented, and the foreign particles contained in the ink can be purged without consuming much ink needlessly.

Ink jet recording apparatus having cleaning means for the cleaning of the nozzle surface of an ink jet head

An ink jet head cleaning apparatus is provided which includes a wiping unit which performs a wiping operation for a nozzle surface of an ink jet head and a suction unit which performs a sucking operation for the nozzle surface. An operation OFF condition of the wiping unit and an operation OFF condition of the suction unit is detected, and the wiping unit and the suction unit are actuated selectively in accordance with the operation OFF condition thus detected. If an elapsed time after the wiping operation is longer than a first predetermined time, the wiping unit is actuated, and if an elapsed time after the sucking operation is longer than a second predetermined time, the suction unit is actuated. The first predetermined time is longer than the second predetermined time.

Ink jet head cleaning apparatus and ink jet recording apparatus

A mechanism is provided for allowing a wipe member formed of an elastic material to abut against a nozzle plate in which a plurality nozzles communicating with a pressure chamber for holding ink therein are arranged, moving the wipe member along the nozzle plate to remove ink and foreign particles remaining in the nozzle plate, and switching the position of abutment of the wipe member against the nozzle plate, whereby satisfactory sweeping capability of the wipe member can be maintained without providing a wipe member cleaning mechanism and performing the work of replacing of the wipe member with another.

Ink Jet recording apparatus having maintenance means for cleaning an ink jet recording head

There is here disclosed a manual paper feeder attached to an image forming apparatus including at least an image data receiving portion and an image forming device, and the manual paper feeder comprises a manual feed unit for supplying a paper sheet by mounting the paper sheet by a user; and a paper sheet release unit including at least a paper feed roller for carrying the paper sheets mounted in the manual feed unit; a frictional separation member for carrying the paper sheets by the frictional force while holding the manually supplied paper sheets between the frictional separation member itself and the paper feed roller; and a frictional force variable mechanism for changing the frictional force for holding the paper sheet between the paper feed roller and the frictional separation member.

Growing community of inventors

Kawasaki, Japan

Hideyuki Akaba