Method, system, and device for supplying electrical energy through electrical conductors adjacent to electrolyte solution environments

• US 10,315,418 B2
• Filed: 03/21/2016
• Issued: 06/11/2019
• Est. Priority Date: 03/20/2015
• Status: Active Grant

• Current Assignee: Archipelago Technology Group, Ltd.
• Original Assignee: Archipelago Technology Group, Ltd.
• Inventors: Newcombe, Guy Charles Fernley, Mace, Daniel Richard, Hastings, Nicholas James
• Primary Examiner(s): Nguyen, Lam S
• Application Number:
  US15/558,495
• Publication Number:
  US 20180079208A1
• Time in Patent Office: 1,177 Days
• Field of Search: 347 10
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04576 controlling heads of electrostatic type
• CPC Class Codes: B41J 2/06 by electric or magnetic field
• CPC Class Codes: H02J 7/0018 using separate charge circuits
• CPC Class Codes: H02J 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices

Abstract

Systems and methods for controlling supply of electrical energy from power source(s) through a plurality of electrical conductors adjacent to a common electrolyte solution are disclosed. The power source(s) are controlled to apply potential difference waveform(s) between pairs of electrical conductors formed from the plurality of electrical conductors such that the potential difference waveform(s) have a magnitude that exceeds a threshold overpotential for the pairs of electrical conductors in the electrolyte solution while sums of an absolute value of a potential difference across a double layer associated with the first electrical conductor in a pair and an absolute value of a potential difference across a double layer associated with a second electrical conductor in the pair is maintained below the threshold overpotential. Some or all electrical conductor(s) can be coupled to the power source(s) using respective capacitor(s).

Claims

1. A system for controlling supply of electrical energy from at least one power source through a plurality of electrical conductors adjacent to a common electrolyte solution, the system comprising:

circuitry configured to control the at least one power source to apply a first potential difference waveform between a first pair of electrical conductors from the plurality of electrical conductors; and

a capacitor coupling a first electrical conductor in the first pair to the at least one power source,

wherein the circuitry is configured to control the at least one power source to apply the first potential difference waveform of a magnitude that exceeds a threshold overpotential for the first pair of electrical conductors in the electrolyte solution while maintaining a sum of

(i) an absolute value of a potential difference across a double layer associated with the first electrical conductor in the first pair, and

(ii) an absolute value of a potential difference across a double layer associated with a second electrical conductor in the first pair

below the threshold overpotential for the first pair.

2. The system of claim 1, further comprising:

a second capacitor coupling the second electrical conductor to the at least one power source.

3. The system of claim 1, wherein the circuitry is configured to control the at least one power source to apply a second potential difference waveform between a second pair of electrical conductors from the plurality of electrical conductors, the system further comprising:

a third capacitor coupling a third electrical conductor in the second pair to the at least one power source,

wherein, wherein the circuitry is configured to control the at least one power source to apply the second potential difference waveform of a magnitude that exceeds a threshold overpotential for the second pair of electrical conductors in the electrolyte solution, while maintaining, a sum of

(i) an absolute value of a potential difference across a double layer associated with the third electrical conductor in the second pair, and

(ii) an absolute value of a potential difference across a double layer associated with a fourth electrical conductor in the second pair

below the threshold overpotential for the second pair.

4. The system of claim 3, wherein the first pair of electrical conductors and the second pair of electrical conductors have a common electrical conductor.

5. The system of claim 1, further comprising a first resistor and a second resistor coupled together, the first resistor coupled to the first electrical conductor and the second resistor coupled to the second electrical conductor, the first and second resistors configured to discharge potential difference between the first and second electrical conductors.

6. The system of claim 5, further comprising a control voltage source coupling the first and second resistors, the first and second resistors further configured to discharge potential difference between the first and second electrical conductors and the control voltage source.

7. The system of claim 1, wherein the system is configured to supply electrical energy to a load.

8. The system of claim 7, wherein the load comprises a plurality of piezoelectric actuators of a piezoelectric ink jet printhead.

9. A method of supplying energy from an electrical power source system having at least one power source through a plurality of electrical conductors adjacent to a common electrolyte solution, the method comprising:

controlling the power source system to apply potential differences between electrical conductors in a first pair of electrical conductors selected from the plurality of electrical conductors to maintain a sum of

(i) an absolute value of a potential difference across a double layer associated with a first electrical conductor in the first pair, and

(ii) an absolute value of a potential difference across a double layer associated with a second electrical conductor in the first pair

below a threshold overpotential for the first pair of electrical conductors in the electrolyte solution,

wherein the potential differences applied between the electrical conductors in the first pair are characterized by a waveform having a magnitude exceeding the threshold for the first pair of electrical conductors.

10. The method of claim 9, wherein a magnitude of at least one of the applied potential differences exceeds one and a half times the threshold overpotential for the first pair of electrical conductors for a period shorter than a shortest of double layer charging times associated with the first pair of electrical conductors,

wherein a double layer charging time is a time constant characterizing charging of a double layer associated with an electrical conductor adjacent to an electrolyte solution.

11. The method of claim 9, wherein the energy from the at least one power source is supplied to the first pair of electrical conductors through a first capacitor coupling the first electrical conductor in the first pair to the at least one power source.

12. The method of claim 11, wherein the energy from the at least one power source is supplied to the first pair of electrical conductors through a second capacitor coupling the second electrical conductor in the first pair to the at least one power source.

13. The method of any of claim 9, further comprising:

discharging potential difference between the first electrical conductor in the first pair and a control voltage source using a first resistor coupling the first electrical conductor in the first pair and the control voltage source.

14. The method of claim 9, wherein the energy from the at least one power source is supplied through the plurality of electrical conductors to a load.

15. The method of claim 14, wherein the load is a plurality of piezoelectric actuators of a piezoelectric ink jet printhead.

16. The method of claim 9, wherein:

the waveform comprises a plurality of sub-waveforms of finite duration,

an average potential difference of the potential differences applied between the electrical conductors in the first pair is smaller than the threshold overpotential for the first pair of electrical conductors, and

the average potential difference is calculated over a time interval of the first waveform that is equal to or greater than the shortest double layer charging time associated with the first pair of electrical conductors.

17. The method of claim 16, wherein the waveform has no frequency component below 500 Hz whose magnitude exceeds the threshold overpotential for the first pair of electrical conductors.

18. The method of claim 9, wherein the sum of the absolute values of the potential differences across the double layers associated respectively with the electrical conductors in the first pair is maintained below an absolute value of a smallest of potential differences between any of the plurality of electrical conductors that cause an electrolyte current to flow through the electrolyte solution between the conductors.

19. The method of claim 9, wherein:

the energy is supplied through one or more pairs of electrical conductors, selected from the plurality of electrical conductors, to one or more actuators associated with the one or more pairs of electrical conductors to cause ejection of one or more droplets of the electrolyte solution from at least one of one or more chambers housing the electrolyte solution,

wherein each of the one or more first actuators is configured to cause ejection of a droplet from the at least one chamber upon reaching a respective displacement level.

20. A system for a printhead, the system comprising:

a plurality of actuator electrodes of the printhead;

one or more chambers configured to house an ink adjacent to the plurality of actuator electrodes;

an electronic circuitry configured to control ejection of electrolyte droplets from the ink by controlling a power source system coupled to the system for the printhead,

wherein the electronic circuitry is configured to control the power source system to apply potential differences between the actuator electrodes in each of one or more pairs of actuator electrodes selected from the plurality of actuator electrodes to maintain a sum of

(i) an absolute value of a potential difference across a double layer associated with a first actuator electrode in the pair, and

(ii) an absolute value of a potential difference across a double layer associated with a second actuator electrode in the pair

below a threshold overpotential for the pair of actuator electrodes, in the ink,

wherein the potential differences applied between the actuator electrodes in each pair are characterized by a waveform having a magnitude exceeding the threshold overpotential for the pair of actuator electrodes,

wherein each of the one or more first actuators is configured to cause ejection of a droplet from a respective chamber upon reaching a respective displacement level; and

a reference electrical conductor, electrically shielded from the electrolyte solution, the reference electrical conductor configured to maintain reference data concerning average potentials with respect to ground potential of the actuator electrodes of the printhead and make the reference data available to the electronic circuitry.