Fluid ejection device and medical apparatus

• US 9,737,327 B2
• Filed: 03/27/2014
• Issued: 08/22/2017
• Est. Priority Date: 03/28/2013
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kojima, Hideki, Sekino, Hirokazu
• Primary Examiner(s): Miles, Jonathan
• Assistant Examiner(s): Mannan, Mikail
• Application Number:
  US14/227,374
• Publication Number:
  US 20140296895A1
• Time in Patent Office: 1,244 Days
• Field of Search: 606167
• CPC Class Codes: A61B 17/3203 Fluid jet cutting instruments
• CPC Class Codes: A61B 2017/00154 pulsed
• CPC Class Codes: A61B 2560/02 Operational features

Abstract

A fluid ejection device which ejects a fluid includes: an ejection tube which ejects the fluid; a fluid chamber which communicates with the ejection tube; a piezoelectric element capable of changing a volume of the fluid chamber; a controller which controls a drive voltage applied to the piezoelectric element; and a fluid supplying unit which supplies the fluid to the fluid chamber at a predetermined flow rate. If a maximum frequency available to be set of the drive voltage is fmax [Hz] and an amount of change in the volume of the fluid chamber when a maximum value available to be set of the drive voltage is applied to the piezoelectric element to drive the piezoelectric element is V1 [ml], the fluid supplying unit supplies the fluid at the predetermined flow rate above V1×fmax [ml/s].

Claims

1. A fluid ejection device which ejects a fluid, comprising:

an ejection tube which ejects the fluid;

a fluid chamber which communicates with the ejection tube;

a fluid supplying unit which supplies the fluid to the fluid chamber at a predetermined flow rate;

a pulsation generator which causes the fluid in the fluid chamber to be ejected from the ejection tube; and

a controller which controls operation of the pulsation generator to cause the fluid to be ejected periodically from the ejection tube;

wherein a maximum frequency at which the controller causes the fluid to be ejected is fmax [Hz], and

an amount of change in volume of the fluid chamber when the controller causes the pulsation generator to operate by applying a maximum value of a drive voltage is V1 [ml],

the fluid supplying unit is configured to supply the fluid at the predetermined flow rate above V1×

fmax [ml/s], such that the predetermined flow rate is maintained even when the drive voltage is lower than the maximum value or when the frequency of the drive voltage is lower than the maximum frequency.

2. The fluid ejection device according to claim 1, wherein the fluid supplying unit supplies the fluid at the predetermined flow rate below V1×

2.0×

fmax [ml/s].

3. The fluid ejection device according to claim 1, wherein when the fluid in a volume V1 [ml] is ejected from the ejection tube by driving the pulsation generator once, if a volume of the fluid ejected from the ejection tube together with the fluid of the volume V1 [ml] by an inertial effect of the fluid is V2 [ml],

the fluid supplying unit supplies the fluid at the predetermined flow rate equal to or above (V1+V2)×

fmax [ml/s].

4. The fluid ejection device according to claim 3, wherein the volume V2 is V1×

0.007.

5. A medical apparatus comprising the fluid ejection device according to claim 1.

6. A medical apparatus comprising the fluid ejection device according to claim 2.

7. A medical apparatus comprising the fluid ejection device according to claim 3.

8. A medical apparatus comprising fluid ejection device according to claim 4.