Device and method for determining the speed of printing of a fiber and the length of a printed fiber

Patent metadata

Field	Value
Publication number	US-12162207-B2
Application number	US-202017609311-A
Country	US
Kind code	B2
Filing date	May 5, 2020
Priority date	May 7, 2019
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

The method for determining the speed of printing of a fiber and the length of a printed fiber comprises: supplying ink to a nozzle; forming an ink drop at the exit of said nozzle; generating an ink jet carrying a net electrostatic charge; deflecting said ink jet periodically by one or a plurality of jet-deflection electrodes; collecting the ink jet on a substrate repetitively forming a printed motif by means of a continuous fiber; determining the width of the printed motif; calculating the speed of printing of fiber from the frequency of the jet-deflection signal and the width of the printed motif; calculating the length of fiber printed in a time interval from the frequency of the jet-deflection signal and from the width of the printed motif.

First claim

The invention claimed is:

1. A method, comprising:
supplying an ink to a nozzle;
forming an ink drop at an exit of the nozzle;
generating a continuous ink jet from the ink drop, wherein the continuous ink jet carries a net electrostatic charge;
deflecting the continuous ink jet by applying a periodically repeating jet deflection signal to one or more jet deflection electrodes;
collecting the continuous ink jet on a substrate to form a continuous fiber on the substrate, wherein the continuous fiber collected in a period of the periodically repeating jet deflection signal forms a printed motif;
determining a width of the printed motif formed during the period of the periodically repeating jet deflection signal; and
determining a speed of printing the continuous fiber as a product of a frequency of the periodically repeating jet deflection signal and a length of the continuous fiber collected in the period of the periodically repeating jet deflection signal, wherein the length of the continuous fiber collected in the period is determined based on a predefined function of the width of the printed motif.

2. The method according to claim 1 , wherein the deflecting comprises deflecting the continuous ink jet from a default trajectory in one direction or two different directions within a plane that is normal to the default trajectory.

3. The method according to claim 1 , wherein generating the continuous ink jet comprises applying an electrostatic field between the nozzle and the substrate.

4. The method according to claim 1 , wherein supplying the ink comprises flowing the ink from a reservoir to the nozzle continuously, wherein the ink comprises a polymer solution or a polymer melt.

5. The method according to claim 1 , wherein determining the speed of printing of the continuous fiber is performed continuously when collecting the continuous ink jet on the substrate.

6. The method according to claim 1 , wherein determining the width of the printed motif comprises analyzing images of a printed item formed by the printed motif.

7. The method according to claim 1 , wherein collecting the continuous ink jet comprises causing relative movement between the substrate and the nozzle while the continuous ink jet is deflected.

8. The method according to claim 1 , wherein collecting the continuous ink jet comprises moving the substrate or the nozzle in a plane that is normal to a default trajectory of the continuous ink jet.

9. The method according to claim 1 , further comprising printing an object comprising a plurality of printed motifs and causing relative movement between the substrate and the nozzle such that the plurality of printed motifs form a motif band.

10. The method according to claim 1 , further comprising printing an object comprising a plurality of printed motifs and keeping the substrate fixed in position relative to the nozzle such that the object comprises a plurality of stacked layers, wherein each stacked layer corresponds to one of the plurality of printed motifs.

11. The method according to claim 1 , further comprising setting an amplitude of the periodically repeating jet deflection signal above a predefined threshold such that the width of the printed motif is independent of the amplitude of the periodically repeating jet deflection signal.

12. The method according to claim 1 , wherein the length of the continuous fiber collected in the period is determined as two times a square root of a square of the width of the printed motif plus a square of a distance translated by the substrate in half of the period.

13. The method according to claim 1 , wherein the length of the continuous fiber collected in the period is determined as two times the width of the printed motif divided by a sine of an angle between a first direction of deflecting the continuous ink jet and a second direction of translating the substrate.

14. The method according to claim 1 , wherein the length of the continuous fiber collected in the period is determined as a product of the width of the printed motif and Pi (π).

15. A device, comprising:
a nozzle configured to generate a continuous ink jet, wherein the continuous ink jet carries a net electrostatic charge;
one or more jet deflection electrodes configured to deflect the continuous ink jet periodically in response to application of a periodically repeating jet deflection signal to form a continuous fiber on a substrate, wherein the periodically repeating jet deflection signal is configured to cause the continuous fiber to form a printed motif during a period of the periodically repeating jet deflection signal; and
a computer configured to determine a width of the printed motif, determine a length of the continuous fiber formed during the period based on a predefined function of the width of the printed motif, and determine a speed of printing the continuous fiber as a product of a frequency of the periodically repeating jet deflection signal and the length of the continuous fiber formed during the period.

16. The device according to claim 15 , further comprising one or more waveform generators configured to generate a voltage signal provided to the one or more jet deflection electrodes as the periodically repeating jet deflection signal.

17. The device according to claim 16 , further comprising one or more amplifiers connected to the one or more jet deflection electrodes and configured to amplify the voltage signal generated by the one or more waveform generators.

18. The device according to claim 15 , wherein the computer is configured to control at least one of deflection of the continuous ink jet and relative movement of the substrate with respect to the nozzle.

19. The device according to claim 15 , wherein an opening of the nozzle is wider than a diameter of the continuous ink jet.

20. The device according to claim 15 , further comprising one or more cameras configured to capture images of the printed motif, based on which the width of the printed motif can be determined by analyzing the images by the computer.

Assignees

• Univ Rovira I Virgili
• Inst Catalana Recerca Estudis Avancats
• Univ Oregon

Inventors

• Liashenko Ievgenii
• Codina Andreu Cabot
• Llompart Joan Rosell

Classifications

• B29C64/209

  Heads; Nozzles · CPC title

• B33Y30/00

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

• B33Y10/00

  Processes of additive manufacturing · CPC title

• D01D5/0092

  characterised by the electrical field, e.g. combined with a magnetic fields, using biased or alternating fields · CPC title

• B33Y50/02

  for controlling or regulating additive manufacturing processes · CPC title