Pin-actuated printhead

Patent metadata

Field	Value
Publication number	US-9757900-B2
Application number	US-201514717560-A
Country	US
Kind code	B2
Filing date	May 20, 2015
Priority date	May 20, 2015
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

A pin actuated printhead includes an orifice through which a material is ejected, a chamber to hold the material to be ejected, a channel connecting the chamber to the orifice, and an actuated pin, to enter the orifice and to eject the material from the orifice. The printhead is configured to eject a material with a viscosity of 10,000 cP or more at an elevated temperature.

First claim

The invention claimed is:

1. A pin actuated printhead, comprising:
a plurality of orifices through which a material is ejected;
at least one chamber to hold the material to be ejected at an elevated temperature of 100° C. or more;
a plurality of channels connecting the at least one chamber to the plurality of orifices; and
a plurality of actuated pins, to enter the plurality of orifices and to eject drops of the material from the plurality of orifices,
wherein, the printhead is configured to eject a material with a viscosity of 10,000 cP or more at the elevated temperature, and
wherein, the at least one chamber is configured to hold the material at a pressure of 25 psi or greater to support a firing frequency of the plurality of actuated pins between 100 Hz and 2000 Hz.

2. The printhead of claim 1 wherein, in a first, open, position, the plurality of actuated pins allows material to enter into an associated orifice, and wherein in a second, closed, position, the plurality of actuated pins blocks material in an associated channel from entering the associated orifice, while simultaneously, entering the associated orifice and ejecting the material therewith.

3. The printhead of claim 2 , wherein a duration of time of each of the actuated pins in the first, open, position determines a volume of the drop of material ejected.

4. The printhead of claim 2 , wherein each orifice is configured to eject a drop of material with a diameter between 100 μm and 300 μm, and
wherein, the firing frequency of the plurality of actuated pins is between 500 Hz and 1500 Hz.

5. The printhead of claim 2 , wherein in the second, closed, position, each of the actuated pins protrudes past a plane defining an outer surface of the orifice.

6. The printhead of claim 1 , further comprising a plurality of pin chambers to guide a movement of the plurality of actuated pins.

7. The printhead of claim 1 , further comprising a plurality of actuator modules to move the plurality of actuated pins,
wherein the plurality of actuated pins move with a velocity of 1 M/s or greater and decelerate at a rate of 20 M/sec 2 or greater.

8. The printhead of claim 7 , wherein the plurality of actuator modules comprise at least one of electromagnetic actuators and piezo-electric actuators, and
wherein the plurality of actuated pins move with a velocity of 5 M/s or greater.

9. The printhead of claim 8 , wherein the at least one chamber holds the material to be ejected at an elevated temperature of 200° C. or more and wherein the material is an engineering polymer with a viscosity of 50,000 cP or more at 200° C.

10. The printhead of claim 9 , wherein the material has a viscosity of 500,000 cP or more at 230° C.

11. The printhead of claim 1 , wherein the at least one chamber is configured to hold the material at a pressure between 50 psi and 150 psi.

12. The printhead of claim 10 , wherein the at least one chamber is configured to hold the material at an elevated temperature of 300° C. or more.

13. The printhead of claim 1 , wherein the at least one chamber comprises a plurality of chambers, each one of the plurality of chambers is associated with one or more of the plurality of orifices, and wherein each one of the plurality of chambers provides material to the associated orifices.

14. The printhead of claim 13 , where said plurality of chambers hold a plurality of different materials, each chamber providing material to the associated orifices.

15. The printhead of claim 7 , wherein the plurality of actuator modules are spaced apart from the at least one chamber, the plurality of orifices, and material so as to enable heating of the at least one chamber, the plurality of orifices, and material to a temperature that is higher than that of the actuator modules.

16. The printhead of claim 1 , where said plurality of actuated pins comprise a metallic wire.

17. The printhead of claim 1 , where said plurality of actuated pins are coated with a low adhesion coating to facilitate the separation of the ejected material from the tip of the plurality of actuated pins.

18. The printhead of claim 7 , further comprising a plurality of pin chambers to guide a movement of the plurality of actuated pins, wherein the plurality of actuated pins have a stepped configuration and the plurality of pin chambers are configured to engage the stepped configuration of the plurality of actuated pins to stop a movement of the plurality of actuated pins.

19. The printhead of claim 7 , further comprising a plurality of pin chambers to guide a movement of the plurality of actuated pins, wherein the plurality of actuated pins have a stepped configuration and the plurality of pin chambers are configured to engage the stepped configuration of the plurality of actuated pins to provide a seal.

20. The printhead of claim 7 , wherein each of the plurality of orifices is associated with one of the plurality of actuator modules, and the plurality of actuators modules are spaced apart from one another at a distance that is greater than a spacing between their associated orifices.

21. The printhead of claim 3 , wherein the timing for each one of the plurality of actuated pins is controlled such that the drops of material ejected by each one of the plurality of actuated pins are of a consistent size.

22. The printhead of claim 2 , wherein a duration of time of each one of the plurality of actuated pins in the first, open, position is controlled such that the drops of material ejected can be varied in size.

23. The printhead of claim 1 , where said printhead is spaced apart from a surface receiving the drops of ejected material such that the drops of ejected material becomes airborne when traveling from said orifices to said receiving surface.

24. The printhead of claim 1 , where said printhead is spaced close to a surface receiving the drops of ejected material such that the plurality of actuated pins carry said drops of ejected material to said receiving surface.

25. The printhead of claim 7 , where said plurality of actuators drive the plurality of actuated pins through one of a lever arm or flexure, which amplifies the motion of said plurality of actuators.

Assignees

• Xerox Corp

Inventors

• Nystrom Peter J
• Mandel Barry P
• Hays Andrew W
• Ma Jun
• Mantell David Allen
• Redding Gary D
• Gulvin Peter M

Classifications

• B29C64/209 Primary

  Heads; Nozzles · CPC title

• B29C64/20

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B29C64/112 Primary

  using individual droplets, e.g. from jetting heads · CPC title

• B29C67/0007 Primary

  Manufacturing coloured articles not otherwise provided for, e.g. by colour change · CPC title

• B33Y30/00

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title