System and method for adjusting printhead operations in a direct-to-object printer having a fixed printhead array

Patent metadata

Field	Value
Publication number	US-9975327-B1
Application number	US-201715598807-A
Country	US
Kind code	B1
Filing date	May 18, 2017
Priority date	May 18, 2017
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A direct-to-object printer includes a plurality of imaging devices that generates image data of an object secured in a holder before the holder and the object pass a plurality of printheads for printing an ink image on the object. A controller receives the image data and converts it to an object profile. The controller operates ejectors in the printheads with reference to the object profile to attenuate inconsistent ink image density and ink image distortion.

First claim

What is claimed is:

1. A printing system comprising:
a plurality of printheads, each printhead in the plurality of printheads being configured to eject marking material;
a member having a first end and a second end, the plurality of printheads being positioned opposite the member and between the first end and the second end of the member;
a holder configured to hold an object and to move along the member between the first end and the second end of the member;
an actuator operatively connected to the holder to enable the actuator to move the holder along the member to enable the object to move past the printheads to receive marking material from the printheads in the plurality of printheads;
a plurality of imaging device, the plurality of imaging devices being positioned between the first end of the member and the plurality of printheads, each imaging device in the plurality of imaging devices being configured to generate image data of a portion of the object opposite the imaging device as the object passes the plurality of imaging devices; and
a controller operatively connected to the plurality of printheads, the actuator, and the plurality of imaging devices, the controller being configured to operate the actuator to move the holder and the object along the member, to operate the imaging devices to generate image data of the object in response to the object being opposite the plurality of imaging devices, to generate an object profile with reference to the generated image data received from the imaging devices, and to operate ejectors within the printheads of the plurality of printheads with reference to the generated object profile.

2. The printing system of claim 1 wherein the plurality of imaging devices is a plurality of cameras operatively connected to the controller for delivery of the image data generated by each camera in the plurality of cameras to the controller.

3. The printing system of claim 2 wherein the printheads in the plurality of printheads are fixed printheads.

4. The printing system of claim 3 , the controller being further configured to operate ejectors that are further from the object than ejectors closer to the object at a first frequency and to operate the ejectors closer to the object at a second frequency, the first frequency being greater than the second frequency.

5. The printing system of claim 4 , the controller being further configured to operate ejectors that are further from the object than ejectors closer to the object before operating the ejectors closer to the object to enable drops of marking material from the ejectors further from the object to arrive at the object simultaneously with drops ejected from the ejectors closer to the object.

6. The printing system of claim 3 , the controller being further configured to operate ejectors that are further from the object than ejectors closer to the object before operating the ejectors closer to the object to enable drops of marking material from the ejectors further from the object to arrive at the object simultaneously with drops ejected from the ejectors closer to the object.

7. The printing system of claim 6 , the controller being further configured to operate ejectors that are further from the object than ejectors closer to the object at a first frequency and to operate the ejectors closer to the object at a second frequency, the first frequency being greater than the second frequency.

8. The printing system of claim 3 further comprising:
an ultraviolet (UV) lamp configured to emit light in an UV range to cure UV curable marking material ejected from the plurality of printheads.

9. The printing system of claim 3 wherein the plurality of cameras are arranged in semi-circular pattern opposite the member.

10. The printing system of claim 3 , the controller being further configured to operate the actuator to maintain the holder and the object opposite the plurality of cameras for a predetermined period of time.

11. The printing system of claim 3 , the controller being further configured to identify an object surface area ratio with reference to the object profile.

12. The printing system of claim 3 , the controller being further configured to identify a printhead-to-object distance with reference to the object profile.

13. A method for operating a printer comprising:
operating with a controller an actuator operatively connected to a holder to move the holder and an object secured in the holder along a member to which the holder is mounted;
operating with the controller a plurality of imaging devices to generate image data of the object in response to the object being opposite the plurality of imaging devices;
generating with the controller an object profile with reference to the generated image data received from the plurality of imaging devices; and
operating with the controller ejectors within a plurality of printheads with reference to the generated object profile, the printheads in the plurality of printheads being fixed printheads.

14. The method of claim 13 , the operation of the plurality of imaging devices further comprising:
operating a plurality of cameras with the controller to generate the image data.

15. The method of claim 13 further comprising:
operating with the controller ejectors that are further from the object than ejectors closer to the object at a first frequency; and
operating the ejectors closer to the object at a second frequency, the first frequency being greater than the second frequency.

16. The method of claim 15 further comprising:
operating with the controller ejectors that are further from the object than ejectors closer to the object before operating the ejectors closer to the object to enable drops of marking material from the ejectors further from the object to arrive at the object simultaneously with drops ejected from the ejectors closer to the object.

17. The method of claim 14 further comprising:
operating with the controller ejectors that are further from the object than ejectors closer to the object before operating the ejectors closer to the object to enable drops of marking material from the ejectors further from the object to arrive at the object simultaneously with drops ejected from the ejectors closer to the object.

18. The method of claim 17 further comprising:
operating with the controller ejectors that are further from the object than ejectors closer to the object at a first frequency and to operate the ejectors closer to the object at a second frequency, the first frequency being greater than the second frequency.

19. The method of claim 14 further comprising:
operating with the controller an ultraviolet (UV) lamp to emit light in an UV range to cure UV curable marking material ejected from the plurality of printheads.

20. The method of claim 14 further comprising:
operating with the controller the actuator to maintain the holder and the object opposite the plurality of cameras for a predetermined period of time.

21. The method of claim 14 further comprising:
identifying with the controller an object surface area ratio with reference to the object profile.

22. The method of claim 14 further comprising:
identifying with the controller a printhead-to-object distance with reference to the object profile.

Assignees

• Xerox Corp

Inventors

• Yang Xin
• Mcconville Paul J
• Steurrys Christine A
• Stookey David R
• Frachioni Martin L
• Breed Dale R

Classifications

• B41J3/4073

  Printing on three-dimensional objects not being in sheet or web form, e.g. spherical or cubic objects (B41J3/283, B41J3/286 take precedence; building up a 3D object using individual droplets from jetting heads B29C64/112) · CPC title

• B41J2/04586

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

• B41J11/002

  Curing or drying the ink on the copy materials, e.g. by heating or irradiating · CPC title

• B41J2/21

  for multi-colour printing · CPC title

• B41J3/543 Primary

  with multiple inkjet print heads (B41J2/17503, B41J2/2103 take precedence) · CPC title