Printing apparatus
A printing apparatus includes an ejection unit that forms an image on a print medium by ejecting liquid from an ejection port using drive of an ejection energy generation element in a pressure chamber, the liquid flowing into the pressure chamber from a first flow passage, a circulation unit circulates the liquid in a circulation flow passage including the first flow passage, the pressure chamber, and a second flow passage to allow the liquid to flow to outside of the pressure chamber, a recovery unit performs a recovery operation of the ejection unit, and a control unit stops the circulation unit before completion of the print operation when the recovery operation is to be performed after the print operation, such that a flow velocity at a timing of the completion of the print operation is a flow velocity higher than a flow velocity at which an ejection characteristic is maintained.
1 . A printing apparatus comprising:
an ejection unit configured to perform a print operation of forming an image on a print medium by ejecting liquid from an ejection port by using drive of an ejection energy generation element provided in a pressure chamber, the liquid flowing into the pressure chamber from a first flow passage;
a circulation unit configured to circulate the liquid in a circulation flow passage including the first flow passage, the pressure chamber, and a second flow passage configured to allow the liquid in the pressure chamber to flow to an outside of the pressure chamber;
a recovery unit configured to perform a recovery operation of the ejection unit; and
a control unit configured to stop the circulation unit before completion of the print operation by the ejection unit in a case when the recovery operation is to be performed after the print operation,
wherein the control unit stops the circulation unit before the completion of the print operation such that a flow velocity at a timing of the completion of the print operation is a flow velocity higher than a flow velocity at which an ejection characteristic is maintained.
2 . The printing apparatus according to claim 1 , wherein the control unit determines an execution timing of the recovery operation depending on a timing at which the circulation unit is stopped.
3 . The printing apparatus according to claim 1 , wherein the flow velocity at which the ejection characteristic is maintained varies depending on a print mode in which the print operation is performed.
4 . The printing apparatus according to claim 1 , wherein the flow velocity at which the ejection characteristic is maintained varies depending on a type of the liquid.
5 . The printing apparatus according to claim 1 , wherein the control unit causes the recovery unit to execute the recovery operation after a first time elapses, the first time being a time it takes for a flow velocity of the liquid in the circulation flow passage to reach or to fall below a predetermined flow velocity from the stop of the circulation unit.
6 . The printing apparatus according to claim 5 , wherein the predetermined flow velocity is a flow velocity that is determined depending on a type of the recovery unit and at which execution of the recovery operation is allowed.
7 . The printing apparatus according to claim 5 , wherein the control unit does not execute the recovery operation while the flow velocity is not equal to or lower than the predetermined flow velocity.
8 . The printing apparatus according to claim 1 , wherein the control unit is configured to execute the recovery operation after time obtained by adding a second time to a predetermined wait time elapses, the second time being a time it takes from the completion of the print operation to completion of a preliminary operation performed before the execution of the recovery operation by the recovery unit, and
the predetermined wait time is determined based on a third time from the stop of the circulation unit to the completion of the print operation.
9 . The printing apparatus according to claim 8 , wherein the recovery unit executes the recovery operation depending on a type of the recovery operation, a member of the recovery unit, and a recovery sequence including a combination of the type of the recovery operation and the member of the recovery unit, and
the second time varies depending on the recovery operation depending on the recovery sequence.
10 . The printing apparatus according to claim 1 , further comprising a print head including a plurality of the ejection units capable of ejecting multiple types of liquids, respectively,
wherein the recovery unit applies the recovery operation to each of the plurality of ejection units, and
the control unit determines a timing of the recovery operation common to the plurality of ejection units.
11 . The printing apparatus according to claim 1 , wherein, in the case when the recovery operation is a predetermined recovery operation, the control unit does not stop the circulation unit before the completion of the print operation.
12 . The printing apparatus according to claim 11 , wherein the predetermined recovery operation includes an operation of sucking the ejection unit.
13 . The printing apparatus according to claim 1 , wherein, in the case when the recovery operation is not to be performed after the print operation, the control unit does not stop the circulation unit before the completion of the print operation.