Liquid ejection device actuator unit and liquid ejection device handpiece

1. A liquid ejection device actuator unit which is fitted to a liquid ejection device nozzle unit including a liquid chamber of which an inside volume is variable by deformation of a liquid chamber side diaphragm and an ejection tube which ejects a liquid from the liquid chamber, the liquid ejection device actuator unit comprising:

a movable plate which comes into contact with the liquid chamber side diaphragm;

a piezoelectric element which comes into contact with the movable plate at one end of the piezoelectric element in an expansion or contraction direction to deform the movable plate; and

a support member which comes into contact with the piezoelectric element at other end of the piezoelectric element in the expansion or contraction direction,

wherein at least one of a contact portion of the movable plate and the piezoelectric element and a contact portion of the piezoelectric element and the support member is adhered by a hard material containing adhesive in which a hard material with a larger elastic modulus than a hardened adhesive is mixed.

2. The liquid ejection device actuator unit according to claim 1 ,

wherein the movable plate includes a piston and a piezoelectric element side diaphragm,

wherein a part of the piezoelectric element side diaphragm is fixed to a housing accommodating the piezoelectric element,

wherein the piston and the piezoelectric element side diaphragm come into contact with each other,

wherein the piezoelectric element and the movable plate are adhered by adhering the piezoelectric element and the piston, and

wherein the liquid chamber side diaphragm comes into contact with the movable plate by bringing the liquid chamber side diaphragm into contact with the piezoelectric element side diaphragm.

3. The liquid ejection device actuator unit according to claim 2 ,

wherein the piston and the piezoelectric element side diaphragm are adhered by the hard material containing adhesive.

4. A liquid ejection device handpiece comprising:

a liquid chamber of which an inside volume is variable by deformation of a diaphragm;

a piezoelectric element which comes into contact with the diaphragm at one end of the piezoelectric element in an expansion or contraction direction to deform the diaphragm; and

a support member which comes into contact with the piezoelectric element at other end of the piezoelectric element in the expansion or contraction direction; and

an ejection tube which ejects a liquid supplied to the liquid chamber from the liquid chamber,

wherein at least one of a contact portion of the diaphragm and the piezoelectric element and a contact portion of the piezoelectric element and the support member is adhered by a hard material containing adhesive in which a hard material with a larger elastic modulus than a hardened adhesive is mixed.

5. A liquid ejection device actuator unit fitted to a liquid ejection device nozzle unit including an ejection tube which ejects a liquid, the liquid ejection device actuator unit comprising:

a movable plate which forms a liquid chamber of which an internal volume is variable when the liquid ejection device actuator unit is fitted to the liquid ejection device nozzle unit;

a piezoelectric element which comes into contact with the movable plate at one end of the piezoelectric element in an expansion or contraction direction to deform the movable plate; and

a support member which comes into contact with the piezoelectric element at other end of the piezoelectric element in the expansion or contraction direction,

wherein at least one of a contact portion of the movable plate and the piezoelectric element and a contact portion of the piezoelectric element and the support member is adhered by a hard material containing adhesive in which a hard material with a larger elastic modulus than a hardened adhesive is mixed.