Ink-jet recording apparatus

An ink-jet recording apparatus comprising:

• a recording head that has at least one ink nozzle and performs recording onto a recording medium by ejecting ink from the ink nozzle;
• an ink supply source that stores ink to be supplied to the recording head;
• an ink passage that is connected to the ink supply source to supply ink from the ink supply source to the recording head;
• an air trap chamber that has an upper wall, a bottom wall, side walls and is connected to the ink passage to store air generated in the ink passage;
• a purge device that generates an ink-flow that flows from the air trap chamber to the recording head and is faster than an ink-flow generated at the recording operation;
• wherein the air trap chamber further includes:
• a rib that protrudes from the upper wall of the air trap chamber so as to extend in a direction orthogonal to an ink-flow direction;
• and
• an air storage portion that is defined by the rib and the upper wall provided downstream of the rib in the ink-flow direction to store a predetermined amount of air even when the high-speed ink-flow is generated by the purge device.

A computer program embodied on a computer readable storage medium for performing a reset purging operation on an ink-jet recording apparatus, where said ink-jet recording apparatus includes a recording head unit, an airtrap unit, a purge unit, and a purge motor, the computer program comprising:

• code for moving the recording head unit to a position adjacent to the purge unit;
• code for directing the purge unit to attach to the recording head unit;
• code for directing the purge motor to operate the purge unit to apply a suction force to the recording head such that a portion of air trapped in the air trap unit is discharged and a remaining portion of air trapped in the air trap unit is retained in the air trap unit;
• and
• code for directing the purge unit to detach from the recording head unit.

A method for discharging an air bubble contained within an airtrap unit of an inkjet recording apparatus, where the airtrap unit includes a first chamber, a second chamber, a third chamber, a first connecting portion for connecting the first chamber and the second chamber, and a second connecting portion for connecting the second chamber with the third chamber, said method comprising the steps of:

• (1) applying a pressure to the airtrap unit;
• (2) generating an inkflow from the first chamber to the second chamber, via the first connecting portion, such that the air bubble is transferred from the first chamber to the second chamber;
• (3) generating an inkflow from the second chamber to the third chamber, via the second connecting portion, such that the air bubble is transferred from the second chamber to the third chamber and discharge from the airtrap unit;
• (4) retaining a portion of the air bubble in the second chamber;
• and
• (5) returning the retained portion of the air bubble to the first chamber to absorb a kinetic pressure generated by the operation of the ink-jet recording apparatus.

A method for discharging an air bubble contained within an airtrap unit of an ink-jet recording apparatus, where the airtrap unit includes a first chamber, a second chamber, a third chamber, a first connecting portion for connecting the first chamber and the second chamber, and a second connecting portion for connecting the second chamber with the third chamber, said method comprising the steps of:

• (1) applying a pressure to the airtrap unit;
• (2) generating an inkflow from the first chamber to the second chamber via the first connecting portion;
• (3) generating an inkflow from the second chamber to the third chamber via the second connecting portion;
• (4) retaining a first portion of the air bubble in the first chamber, retaining a second portion of the air bubble in the second chamber and discharging a third portion of the air bubble from the third chamber;
• and
• (5) returning the second retained portion of the air bubble to the first chamber;
• (6) combining the second retained portion of the air bubble with the first retained portion of the air bubble to create a single retained portion of the air bubble to absorb a kinetic pressure generated by the operation of the ink-jet recording apparatus.

An ink-jet recording apparatus comprising:

• a recording head that has at least one ink nozzle and performs recording onto a recording medium by ejecting ink from the ink nozzle;
• an ink supply source that stores ink to be supplied to the recording head;
• an ink passage that is connected to the ink supply source to supply ink from the ink supply source to the recording head;
• an air trap chamber that has an upper wall, a bottom wall, side walls and is connected to the ink passage to store air generated in the ink passage;
• and,
• a purge device that generates an ink-flow that flows from the air trap chamber to the recording head and is faster than an ink-flow generated at the recording operation;
• wherein the air trap chamber further includes:
• a partition that divides the air trap chamber into a first chamber connecting with the ink supply source, a second chamber, and a first connecting portion that communicates the first chamber with the second chamber above the partition, where a surface of the partition is made of resin material which is nonrepellant to ink;
• and
• a flow resistant member that further divides the air trap chamber and defines a third chamber at a recording head side and connects the first chamber and a lower end of the second chamber with the recording head, the flow resistant member being provided to allow the ink to flow from the first chamber to the third chamber through the flow resistant member and to also provide resistance to the high-speed ink-flow generated by the purge device such that air is separated from the ink which enters the air trap chamber and is trapped at an upper portion of the first chamber, and the air trapped in the first chamber is discharged from the nozzles by a suction supplied by the purge device that generates the high-speed ink-flow that passes the first, second and third chambers in order.