Devices, systems, and methods for supplying makeup air through ports in a carrier plate of a printing system
A printing system comprises a print fluid deposition assembly, a media transport device, and an air flow control system. The print fluid deposition assembly comprises a printhead to eject a print fluid through an opening of a carrier plate to a deposition region. The media transport device holds a print medium against the movable support surface by vacuum suction and transports the print medium through the deposition region. The air flow control system is to flow air through the carrier plate to the movable support surface via a port through the carrier plate on an inboard side the carrier plate and to control a flow rate of the air flowed through the port based on a size of a print medium transported by the media transport device.
1. A printing system, comprising:
a print fluid deposition assembly comprising:
a carrier plate comprising an opening;
a printhead supported by the carrier plate, wherein the printhead is arranged to eject a print fluid through the opening of the carrier plate and to a deposition region of the print fluid deposition assembly; and
a media transport device comprising a movable support surface, the media transport device configured to hold a print medium against the movable support surface by vacuum suction and the movable support surface configured to transport the print medium along a process direction through the deposition region of the print fluid deposition assembly; and
an airflow control system arranged to flow air through the carrier plate to the movable support surface via a port through the carrier plate on an inboard side the carrier plate,
wherein the airflow control system is configured to control a flow rate of the air flowed through the port based on a size of a print medium transported by the media transport device.
2. The printing system of claim 1 , wherein:
the airflow control system is arranged to flow air through the opening in the carrier plate to the movable support surface, and
the airflow control system is configured to selectively flow the air through the opening in the carrier plate based on a location of a print medium transported by the media transport device relative to the printhead.
3. The printing system of claim 2 , wherein:
the media transport device is configured to hold a plurality of print media, including the print medium, by vacuum suction against the movable support surface such that consecutive print media are spaced from each other via an inter-media zone, and
the airflow control system is configured to selectively flow the air through the opening based on a location of the inter-media zone relative to the printhead.
4. The printing system of claim 2 , wherein the airflow control system comprises:
an upstream air supply unit arranged to flow air through the opening at an upstream side of the printhead and a downstream air supply unit arranged to flow air through the opening at a downstream side of the printhead,
wherein the airflow control system is configured to individually control the upstream air supply unit and the downstream air supply unit to selectively flow air through the opening, and
wherein upstream and downstream are defined relative to the process direction.
5. The printing system of claim 4 , wherein the airflow control system comprises an inboard air supply unit arranged to flow air through the port, wherein the airflow control system is configured to control the inboard air supply unit to flow the air through the port independently of the flowing of air through the upstream and downstream air supply units.
6. The printing system of claim 4 , wherein:
the media transport device is configured to hold a plurality of print media, including the print medium, against the movable support surface such that consecutive print media are spaced apart from each other via an inter-media zone,
the airflow control system is configured to control the upstream air supply unit to supply the air when an inter-media zone reaches a first position relative to the printhead, and to cease supplying the air when the inter-media zone reaches a second position relative to the printhead, and
the airflow control system is configured to control the downstream air supply unit to supply the air when an inter-media zone reaches a third position relative to the printhead, and to cease supplying the air when the inter-media zone reaches a fourth position relative to the printhead.
7. The printing system printing system of claim 6 , wherein the first position is upstream of the second and third positions, and the second and third positions are upstream of the fourth position.
8. The printing system printing system of claim 7 , wherein the second position is the same as the third position.
9. The printing system printing system of claim 6 , wherein:
the print medium is a first print medium and wherein a second print medium of the plurality of print media consecutively follows and is upstream of the first print medium, and wherein lead and trail edges of the print media are defined based on the process direction through the deposition region,
the first position corresponds to a trail edge of the first print medium being near the upstream side of the printhead,
the second position corresponds to a lead edge of the second print medium being near the upstream side of the printhead,
the third position corresponds to the trail edge of the first print medium being near the downstream side of the printhead, and
the fourth position corresponds to the lead edge of the second print medium being near the downstream side of the printhead.
10. The printing system of claim 1 , wherein the movable support surface comprises a belt with holes through the belt.
11. The printing system of claim 1 , wherein:
the airflow control system comprises an air source configured to selectively supply the air to the port.
12. The printing system of claim 11 , the airflow control system comprises a controllable valve configured to selectively control a supply of air from the air source to the port.
13. The printing system of claim 11 , wherein the air source comprises a fan.
14. The printing system of claim 1 , further comprising:
a control system configured to automatically control the airflow control system to selectively flow the air through the opening in the carrier plate based on a monitored amount of image blur in printed images.
15. A method of operating a printing system, the method comprising:
transporting a print medium through a deposition region of a printhead of a print fluid deposition assembly of the printing system, wherein the print medium is held against a movable support surface via vacuum suction during the transporting;
ejecting print fluid from a printhead of the print fluid deposition assembly through an opening in a carrier plate supporting the printhead to deposit the print fluid to the print medium in the deposition region; and
controlling an airflow control system to flow air through the carrier plate to the movable support surface via a port through the carrier plate at an inboard side the carrier plate,
wherein the controlling the airflow control system to flow the air via the port comprises controlling a flow rate of the air based on a size of the print medium.
16. The method of claim 15 , further comprising:
controlling the airflow control system to selectively flow air through opening in the carrier plate to the movable support surface based on the location of the print medium.
17. The method of claim 16 , wherein
transporting the print medium comprises transporting a plurality of print media, including the print medium, such that consecutive print media are spaced from each other by an inter-media zone,
the airflow control system comprises an upstream air supply unit and a downstream air supply unit,
controlling the airflow control system to selectively flow air through the opening comprises:
in response to the inter-media zone between the print media reaching a first position relative to the printhead, supplying the air through the opening in the carrier plate from the upstream air supply unit,
in response to the inter-media zone reaching a second position relative to the printhead, ceasing supplying the air from the upstream air supply unit;
in response to the inter-media zone reaching a third position relative to the printhead, supplying the air through the opening in the carrier plate from the downstream air supply unit; and
in response to the inter-media zone reaching a fourth position relative to the printhead, ceasing supplying the air from the downstream air supply unit, and
wherein upstream and downstream are defined relative to a direction of the transporting.
18. The method of claim 17 , wherein the first position is upstream of the second and third positions, and the second and third positions are upstream of the fourth position.
19. The method of claim 17 , wherein the second position is the same as the third position.
20. The method of claim 15 , wherein the transporting, ejecting, and controlling the airflow control system is repeated for a plurality of print media being transported through the deposition region, the method further comprising:
monitoring an amount of image blur in a printed image on at least one of the print media; and
controlling the airflow control system to selectively flow the air based on the location of a respective print medium to be printed relative to the printhead in response to the amount of image blur in the printed image.