FLUID DISCHARGE HEAD

• US 20190322102A1
• Filed: 04/02/2019
• Published: 10/24/2019
• Est. Priority Date: 04/18/2018
• Status: Abandoned Application

• Current Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: Takamura, Jun, Gomi, Takanori
• Application Number:
  US16/372,480
• Publication Number:
  US 20190322102A1
• Time in Patent Office: Days
• CPC Class Codes: B41J 2/0452 reducing demand in current or voltage
• CPC Class Codes: B41J 2/04573 Timing; Delays
• CPC Class Codes: B41J 2/04581 controlling heads based on piezoelectric elements
• CPC Class Codes: B41J 2/04588 using a specific waveform
• CPC Class Codes: B41J 2/0459 Height of the driving signal being adjusted

Abstract

According to one embodiment, a fluid discharge head includes a pressure chamber, an actuator, and an application unit. The pressure chamber accommodates a fluid. The application unit applies the driving signal for discharging a fluid from a nozzle communicating with the pressure chamber to the actuator. The driving signal includes a first pulse for driving the actuator to decrease the pressure of the fluid in the pressure chamber and a second pulse for driving the actuator to increase the pressure of the fluid in the pressure chamber. When a half period of a natural oscillation period of the fluid in the pressure chamber is AL, an application time T of the first pulse satisfies a condition of T<AL. A ratio between a voltage of the first pulse and a voltage of the second pulse is −0.95 to −1.05.

Claims

1. A fluid discharge head, comprising:

a pressure chamber that accommodates a fluid;

an actuator that changes the pressure of the fluid in the pressure chamber according to a driving signal to be applied; and

an application unit that applies the driving signal to the actuator for discharging the fluid from a nozzle communicating with the pressure chamber, wherein

the driving signal comprises a first pulse to decrease the pressure of the fluid in the pressure chamber and a second pulse to increase the pressure of the fluid in the pressure chamber,

an application time T of the first pulse satisfies a condition of T<

AL where AL is a half period of a natural oscillation period of the fluid in the pressure chamber, and

a ratio between a voltage of the first pulse and a voltage of the second pulse is from about −

0.95 to about −

1.05.

2. The head according to claim 1, wherein

the application time T of the first pulse satisfies another condition of T≥

(0.5 AL+0.2 (μ

sec)).

3. The head according to claim 1, wherein

the application time T of the first pulse satisfies another condition of 0.54 AL≤

T≤

0.81 AL.

4. The head according to claim 1, wherein

the application of the second pulse is completed when the pressure of the fluid at a meniscus surface of the nozzle is at a peak.

5. The head according to claim 1, wherein

the actuator comprises two piezoelectric members.

6. The head according to claim 1, further comprising

a plurality of pressure chambers and a corresponding plurality of actuators.

7. The head according to claim 1, wherein

the fluid discharge head is an inkjet head.

8. An inkjet recording apparatus comprising the fluid discharge head according to claim 1.

9. A fluid discharge head, comprising:

a pressure chamber that accommodates a fluid;

an actuator that changes the pressure of the fluid in the pressure chamber according to a driving signal to be applied; and

an application unit that applies the driving signal to the actuator, wherein

the driving signal comprises a first pulse to decrease the pressure of the fluid in the pressure chamber and a second pulse to increase the pressure of the fluid in the pressure chamber, and

an application time T of the first pulse satisfies a condition of T<

0.7 AL where AL is a half period of a natural oscillation period of the fluid in the pressure chamber.

10. The head according to claim 9, wherein

the application time T of the first pulse satisfies another condition of T≥

(0.5 AL+0.2 (μ

sec)).

11. The head according to claim 9, wherein

the application time T of the first pulse satisfies another condition of 0.54 AL≤

T≤

0.81 AL.

12. The head according to claim 9, wherein

the application of the second pulse is completed when the pressure of the fluid at a meniscus surface of the nozzle is at a peak.

13. The head according to claim 9, wherein

the actuator comprises two piezoelectric members.

14. The head according to claim 9, further comprising

a plurality of pressure chambers and a corresponding plurality of actuators.

15. The head according to claim 9, wherein

the fluid discharge head is an inkjet head.

16. An inkjet recording apparatus comprising the fluid discharge head according to claim 9.

17. A fluid discharge method, comprising:

applying a driving signal to an actuator that changes a pressure of fluid in a pressure chamber thereby discharging the fluid from a nozzle communicating with the pressure chamber, wherein

the driving signal comprises a first pulse to decrease the pressure of the fluid in the pressure chamber and a second pulse to increase the pressure of the fluid in the pressure chamber, and at least one of;

an application time T of the first pulse satisfies a condition of T<

AL where AL is a half period of a natural oscillation period of the fluid in the pressure chamber, and a ratio between a voltage of the first pulse and a voltage of the second pulse is from about −

0.95 to about −

1.05, and

an application time T of the first pulse satisfies a condition of T<

0.7 AL where AL is a half period of a natural oscillation period of the fluid in the pressure chamber.

18. The method according to claim 17, wherein

the application time T of the first pulse satisfies another condition of T≥

(0.5 AL+0.2 (μ

sec)).

19. The method according to claim 17, wherein

the application time T of the first pulse satisfies another condition of 0.54 AL≤

T≤

0.81 AL.

20. The method according to claim 17, wherein

the application of the second pulse is completed when the pressure of the fluid at a meniscus surface of the nozzle is at a peak.