Inkjet recording apparatus

Patent metadata

Field	Value
Publication number	US-9757940-B2
Application number	US-201615236948-A
Country	US
Kind code	B2
Filing date	Aug 15, 2016
Priority date	Nov 19, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An inkjet recording apparatus includes a plurality of line heads disposed along a conveyance direction of a recording sheet and including a plurality of nozzles to discharge ink droplets, the plurality of nozzles disposed in a direction perpendicular to the conveyance direction of the recording sheet; a plurality of edge sensors corresponding to respective line heads, to detect a lateral edge of the recording sheet; a plurality of actuators corresponding to the respective line heads, to move to the respective line heads laterally in a sheet width direction; a head position adjustor to determine movement amounts of the respective line heads in accordance with outputs of the plurality of edge sensors; and a failure determiner to obtain outputs of the plurality of edge sensors simultaneously and identify a failure of the plurality of edge sensors based on a combination of the outputs from the plurality of edge sensors.

First claim

What is claimed is:

1. An inkjet recording apparatus, comprising:
a plurality of line heads positioned along a conveyance direction of a sheet, each line head of the plurality of line heads including a plurality of nozzles, each nozzle of the plurality of nozzles configured to discharge ink droplets, the plurality of nozzles positioned in a width direction perpendicular to the conveyance direction of the sheet;
a plurality of sensors, each sensor of the plurality of sensors corresponding to a separate line head of the plurality of line heads, each sensor of the plurality of sensors configured to detect a position of the sheet in the width direction; and
a controller configured to,
receive an output from each sensor of the plurality of sensors, such a that a plurality of outputs is received, and
identify a first failure associated with at least one sensor of the plurality of sensors, based on the received plurality of outputs.

2. The inkjet recording apparatus of claim 1 , further comprising:
a plurality of actuators, each actuator of the plurality of actuators configured to move each line head of the plurality of line heads in the width direction, respectively.

3. The inkjet recording apparatus of claim 1 , wherein the controller is configured to determine a movement magnitude associated with each line head of the plurality of line heads, based on the received plurality of outputs.

4. The inkjet recording apparatus of claim 1 , wherein,
each received output includes an output range;
the output range includes a first abnormal range; and
the controller is further configured to,
identify a second failure based on whether the received plurality of outputs include output ranges that are within the first abnormal range, respectively.

5. The inkjet recording apparatus of claim 4 , wherein the controller is further configured to,
determine whether each sensor of the plurality of sensors is not associated with at least one failure of the first failure and the second failure; and
determine whether a change in a conveyance position of the sheet is within the first abnormal range, based on the received plurality of outputs.

6. The inkjet recording apparatus of claim 4 , wherein the controller is further configured to,
identify a third failure based on a first received output from a first sensor of the plurality of sensors, the first received output indicating that the first sensor is within the first abnormal range, the third failure indicating that the first sensor has failed.

7. The inkjet recording apparatus of claim 4 , wherein the controller is further configured to,
determine whether the received plurality of outputs are within the first abnormal range based on a conveyance time period associated with the sheet, the conveyance time period including a time period associated with a movement of the sheet in the conveyance direction from a first sensor of the plurality of sensors to a second sensor of the plurality of sensors, the first sensor being a farthest upstream sensor of the plurality of sensors, and the second sensor being a farthest downstream sensor of the plurality of sensors.

8. The inkjet recording apparatus of claim 4 , further comprising:
a memory configured to store a control table, the control table including a plurality of combination patterns and a determination result associated with each combination pattern of the plurality of combination patterns, the plurality of combination patterns being based on a difference of the determination result as to whether the received plurality of outputs are within the first abnormal range;
wherein the controller is further configured to identify a third failure based on the control table.

9. The inkjet recording apparatus of claim 8 , wherein,
the memory is configured to and store a flowchart in the memory; and
the controller is further configured to determine, based on the flowchart, whether the received plurality of outputs are within the first abnormal range.

10. The inkjet recording apparatus of claim 4 , wherein the controller is further configured to determine that a first sensor of the plurality of sensors has failed, based on a determination that a received output from the first sensor is in a first range and a received output from one or more remaining sensors of the plurality of sensors is in a second range, the first range being different from the second range.

11. The inkjet recording apparatus of claim 4 , wherein,
the output range of the received output of each sensor of a first sensor of the plurality of sensors and a second sensor of the plurality of sensors includes a normal range, the first abnormal range and a second abnormal range;
the first abnormal range is set as an upper limit, the upper limit being above the normal range; and
the second abnormal range is set as a lower limit, the lower limit being below the normal range.

12. A method, comprising:
receiving a plurality of outputs from a plurality of sensors, each output being received from a separate sensor of the plurality of sensors, each sensor of the plurality of sensors corresponding to a separate line head of a plurality of line heads positioned along a conveyance direction of a sheet, each line head including a plurality of nozzles positioned in a width direction perpendicular to the conveyance direction of the sheet, each nozzle configured to discharge ink droplets, each sensor configured to detect a position of the sheet in the width direction; and
identifying a first failure associated with at least one sensor of the plurality of sensors, based on the received plurality of outputs.

13. The method of claim 12 , further comprising:
determining a movement magnitude associated with each line head of the plurality of line heads, based on the received plurality of outputs.

14. The method of claim 12 , wherein,
each received output includes an output range, the output range including a first abnormal range; and
the method further includes,
identifying a second failure based on whether the received plurality of outputs include output ranges that are within the first abnormal range, respectively.

15. The method of claim 14 , further comprising:
determining whether each sensor of the plurality of sensors is not associated with at least one failure of the first failure and the second failure; and
determining whether a change in a conveyance position of the sheet is within the first abnormal range, based on the received plurality of outputs.

16. The method of claim 14 , further comprising:
identifying a third failure based on a first received output from a first sensor of the plurality of sensors, the first received output indicating that the first sensor is within the first abnormal range, the third failure indicating that the first sensor has failed.

17. The method of claim 14 , further comprising:
determining whether the received plurality of outputs are within the first abnormal range based on a conveyance time period associated with the sheet, the conveyance time period including a time period associated with a movement of the sheet in the conveyance direction from a first sensor of the plurality of sensors to a second sensor of the plurality of sensors, the first sensor being a farthest upstream sensor of the plurality of sensors, and the second sensor being a farthest downstream sensor of the plurality of sensors.

18. The method of claim 14 , further comprising:
determining that a first sensor of the plurality of sensors has failed, based on a determination that a received output f

Assignees

• Hommi Masashi
• Ricoh Co Ltd

Inventors

• Hommi Masashi

Classifications

• B41J2/04586

  controlling heads of a type not covered by groups B41J2/04575 - B41J2/04585, or of an undefined type · CPC title

• B41J11/0095

  Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end · CPC title

• B41J2/2146

  for line print heads · CPC title

• B41J2/0451 Primary

  for detecting failure, e.g. clogging, malfunctioning actuator · CPC title

• B41J25/001 Primary

  Mechanisms for bodily moving print heads or carriages parallel to the paper surface · CPC title