Patent application number | Description | Published |
20100078087 | LIQUID EJECTION APPARATUS - The present invention provides a liquid ejection apparatus capable of precisely controlling a flow rate of liquid in a flow-path. The liquid ejection apparatus is equipped with: an ejection head that is provided with a feed port and a discharge port, and that ejects fed liquid; a feed flow-path that feeds liquid to the feed port; a discharge flow-path that discharges liquid from the discharge port; at least one of the feed flow-path and/or the discharge flow-path equipped with a main pump that pumps a constant flow rate of liquid in the flow-path, a sub pump provided in parallel to the main pump and that pumps liquid in the flow-path, and a detector unit that detects liquid pressure in the flow-path; and a control unit that controls the flow rate of liquid pumped by the sub pump such that the pressure detected achieves a predetermined pressure. | 04-01-2010 |
20100188453 | DROPLET EJECTING APPARATUS - A droplet ejection apparatus includes droplet ejection units each including a supply port and an ejection port, a common supply flow path, a common discharge flow path, supply flow paths that connect the supply port to the common supply flow path, openable mechanisms provided at the supply flow paths, discharge flow paths that connect the ejection port to the common discharge flow path, one-way valves provided at the discharge flow paths, a pressure applying unit, and a controller. When performing a maintenance operation of a selected droplet ejection unit, the controller applies a pressure with the pressure applying unit so that the pressure in the plural discharge flow paths at the common discharge flow path side with respect to the respective one-way valves is higher than the other side, and opens only the openable mechanism corresponding to the selected droplet ejection unit. | 07-29-2010 |
20100188454 | DROPLET EJECTION APPARATUS - A droplet ejection apparatus includes a common flow path; droplet ejection units each respectively including a first distribution port; first flow paths that respectively connect each first distribution port to the common flow path; first open/close mechanisms provided respectively at the first flow paths; a first pressurizing unit that applies a positive pressure to the common flow path; a second open/close mechanisms provided at the common flow path at the first pressurizing unit side of connection portions that connect the common flow path and the respective first flow paths; and a controller. When the second open/close mechanism is closed, the controller opens only one or more first open/close mechanisms corresponding to one or more target droplet ejection units, applies positive pressure to a section of the common flow path at the first pressurizing unit side of the second open/close mechanism, and then opens the second open/close mechanism. | 07-29-2010 |
Patent application number | Description | Published |
20080198207 | PRESSURE ADJUSTMENT APPARATUS AND IMAGE FORMING APPARATUS, AND PRESSURE ADJUSTMENT METHOD AND LIQUID REMAINING AMOUNT DETERMINATION METHOD - A pressure adjustment apparatus for adjusting a pressure of liquid inside a liquid ejection head including nozzles and flow channels includes: a tank; a pump; a buffer chamber; a first switching device; and a second switching device. The tank includes a movable film and a hermetically sealed container of a prescribed volume, the movable film dividing the hermetically sealed container into a gas chamber filled with gas and a liquid chamber filled with the liquid to be supplied to the liquid ejection head. The pump changes a pressure of the gas inside the gas chamber so as to adjust a pressure of the liquid inside the liquid chamber. The buffer chamber is filled with the gas and damps gas-flow pulsations caused by the pump. The first switching device connects and disconnects the buffer chamber and the gas chamber. The second switching device switches between a state where the pump is connected to the gas chamber without through the buffer chamber, and a state where the pump is connected to the buffer chamber. | 08-21-2008 |
20080231650 | BACK PRESSURE ADJUSTMENT APPARATUS FOR LIQUID EJECTION HEAD - The back pressure adjustment apparatus for a liquid ejection head has: a container having a liquid accommodating chamber which is connected to the liquid ejection head and accommodates liquid to be supplied to the liquid ejection head, and a gas accommodating chamber which accommodates gas; a movable film which separates the liquid accommodating chamber and the gas accommodating chamber, and forms a portion of whole walls of the liquid accommodating chamber; and a pressure adjustment device which causes all or a portion of the movable film to deform so as to adjust pressure of the liquid accommodated in the liquid accommodating chamber. | 09-25-2008 |
20090027435 | LIQUID EJECTION APPARATUS, IMAGE FORMING APPARATUS AND LIQUID STORAGE AMOUNT JUDGMENT METHOD - The liquid ejection apparatus has: a sub tank having a liquid chamber which stores liquid, a gas chamber which fills with gas, and a flexible film which divides the liquid chamber from the gas chamber; a liquid tank which is connected to the liquid chamber and stores the liquid; a liquid conveyance device which conveys the liquid between the liquid chamber and the liquid tank; an ejection head connected to the liquid chamber; a control device which carries out control in such a manner that pressure in the gas chamber is controlled to control back pressure of the liquid in the ejection head; a liquid pressure determination device which determines pressure in the liquid chamber; a gas pressure determination device which determines the pressure in the gas chamber; and a liquid storage amount judgment device which judges whether or not an amount of the liquid stored in the liquid chamber is within a tolerable range in which the back pressure of the liquid in the ejection head can be controlled, according to a gas-liquid pressure differential which is a difference between the pressure of the liquid chamber determined by the liquid pressure determination device and the pressure of the gas chamber determined by the gas pressure determination device. | 01-29-2009 |
20090102879 | INKJET RECORDING APPARATUS AND RECORDING METHOD - An inkjet recording apparatus has: a recording head of an inkjet type having a liquid ejection surface where a plurality of nozzles which eject liquid are arranged, a supply port which supplies the liquid to an internal flow channel connected to the plurality of nozzles, and an outlet port which is connected to the supply port via the internal flow channel and through which the liquid in the internal flow channel is expelled; a first liquid chamber which is connected to the supply port of the recording head via a first external flow channel; a second liquid chamber which is connected to the outlet port of the recording head via a second external flow channel; a liquid buffer chamber which stores the liquid supplied from a liquid supply source; a first connecting flow channel which connects the first liquid chamber to the liquid buffer chamber; a second connecting flow channel which connects the second liquid chamber to the liquid buffer chamber; a first pressure determination device which determines an internal pressure of the first liquid chamber; a second pressure determination device which determines an internal pressure of the second liquid chamber; a liquid movement device which moves the liquid between the first liquid chamber, the second liquid chamber and the liquid buffer chamber; and a pressure control device which controls the liquid movement device in accordance with determination results of the first pressure determination device and the second pressure determination device in such a manner that interiors of the first liquid chamber and the second liquid chamber respectively assume prescribed pressures, wherein the pressure control device controls the liquid movement device so as to adjust the internal pressures of the first liquid chamber and the second liquid chamber in such a manner that a prescribed pressure differential between the internal pressures of the first liquid chamber and the second liquid chamber is produced and a prescribed back pressure is applied to the liquid inside the plurality of nozzles of the recording head. | 04-23-2009 |
20100073437 | INKJET RECORDING APPARATUS - An inkjet recording apparatus includes: a recording head including an introduction section, a discharge section and nozzles; a first liquid chamber connected to the introduction section; a second liquid chamber connected to the discharge section; a first buffer tank which is connected to the first liquid chamber and an interior of which is open to air; a second buffer tank which is connected to the second liquid chamber and an interior of which is open to air; and a pressure control device which sets target pressures of the first liquid chamber and the second liquid chamber in such a manner that a prescribed back pressure is applied to the liquid inside the nozzles of the recording head while a prescribed pressure differential is provided between the first liquid chamber and the second liquid chamber, and controls driving of the first pump and the second pump in accordance with determination results of the pressure determination device in such a manner that the internal pressures of the first liquid chamber and the second liquid chamber remain constant at the target pressures, wherein the first buffer tank and the second buffer tank are connected via a flow channel, and at least one of a filter and a deaeration device is provided in the flow channel. | 03-25-2010 |