Excision device and air-bubble detecting method

Abstract

An excision device configured to excise living tissue by ejecting liquid includes: a supplying unit configured to supply liquid to be ejected; a chamber configured to be filled with the supplied liquid; an ejection nozzle connected to the chamber; a drive member configured to be deformed in the direction to reduce the volume of the chamber when a drive voltage is applied more than a case where the drive voltage is not applied; a liquid ejecting unit configured to eject the liquid in the chamber in a pulsed manner from the ejection nozzle by applying the drive voltage to the drive member in a state in which the chamber is filled with the supplied liquid; and an air-bubble detecting unit configured to detect air bubbles in the chamber by detecting an electric current flowing in the drive member when the drive voltage is applied to the drive member.

1 . An excision device configured to excise living tissue by ejecting liquid toward the living tissue comprising:
 a liquid supplying unit configured to supply liquid to be ejected;   a liquid chamber configured to be filled with the supplied liquid;   an ejection nozzle connected to the liquid chamber;   a drive member configured to be deformed in the direction to reduce the volume of the liquid chamber when a drive voltage is applied more than a case where the drive voltage is not applied;   a liquid ejecting unit configured to eject the liquid in the liquid chamber in a pulsed manner from the ejection nozzle by applying the drive voltage to the drive member in a state in which the liquid chamber is filled with the supplied liquid; and   an air-bubble detecting unit configured to detect air bubbles in the liquid chamber by detecting an electric current flowing in the drive member when the drive voltage is applied to the drive member.   
     
     
         2 . The excision device according to  claim 1 , wherein the air-bubble detecting unit is an unit that detects the air bubbles in the liquid chamber by detecting a peak current of the electric current flowing in the driving member. 
     
     
         3 . The excision device according to  claim 1 , wherein
 the liquid ejecting unit is an unit that applies a voltage having a waveform rising to a predetermined maximum voltage and then lowering from the maximum voltage to the drive member, and   the air-bubble detecting unit is an unit that detects the air bubbles in the liquid chamber by detecting an electric current flowing in the drive member when the maximum voltage is applied to the drive member.   
     
     
         4 . The excision device according to  claim 1 , further comprising:
 a storage unit that stores a reference current according to the drive member, wherein   the air-bubble detecting unit is an unit that detects the air bubbles in the liquid chamber by comparing the electric current flowing in the drive member with the reference current stored according to the drive member.   
     
     
         5 . An air-bubble detecting method applied to an excision device including a liquid chamber configured to be filled with liquid to be ejected toward living tissue;
 an ejection nozzle connected to the liquid chamber; and   a drive member configured to be deformed in the direction to reduce the volume of the liquid chamber when a drive voltage is applied more than a case where the drive voltage is not applied for detecting air bubbles in the liquid chamber,   the method comprising:   supplying the liquid into the interior of the liquid chamber;   ejecting the liquid in the liquid chamber from the ejection nozzle by applying the drive voltage to the drive member in a state in which the liquid chamber is filled with the liquid; and   detecting air bubbles in the liquid chamber by detecting an electric current flowing in the drive member when the drive voltage is applied to the drive member.