Method of producing a displacement device

Claim 1

A displacement device comprising: a piezoelectric element (1) expanding and contracting in the longitudinal direction thereof in accordance with an applied voltage; a frame (2) extending along the length of the piezoelectric element (1) and supporting a first end of the piezoelectric element (1); a contact member (5) disposed at a second end of the piezoelectric element (1) and displacing in accordance with expansion and contraction of the piezoelectric element (1); a displacement mechanism (6, 7, 8, 10) supported by the frame (2) and operationally connected to the contact member (5), said displacement mechanism (6, 7, 8, 10) operating in accordance with the displacement of the contact member (5); temperature compensating means (12) in communication with the piezoelectric element (1) for applying a preload to the piezoelectric element (1) and to connect the piezoelectric element (1) to the frame (2) and the contact member (5), said temperature compensating means (12) being deformed in response to temperature changes so as to compensate for deformations of the piezoelectric element (1) due to the temperature changes.

Claim 7

A device as set forth in one of Claims 1 to 5, wherein said displacement mechanism comprises: leaf springs (6, 7) fixed to ends of the contact member (5) and of the frame (2), opposing each other; a rocking block (8) formed at ends of the leaf springs (6, 7); and a rocking (10) arm of which a proximal end is fixed to the rocking block (8).

Claim 8

A device as set forth in one of Claims 1 to 6, wherein a printing wire (11) is attached to the displacement mechanism (6, 7, 8, 10).

Claim 9

A device as set forth in one of Claims 1 to 7, wherein the displacement device is a magnifying displacement device.

Claim 10

A method for producing a displacement device comprising a piezoelectric element wherein the displacement of a column shape piezoelectric element (1) caused by applied voltage is applied by a displacement mechanism (8, 10), the method comprising: assembling frames (2, 4), the contact member (5), and the piezoelectric element (1) in a predetermined order; assembling a temperature compensating member (12) having temperature expansion characteristics reverse to those of the piezoelectric element (1) between the frame (2) and the piezoelectric element (1) and/or between the piezoelectric element (1) and the contact member (5); plastically deforming the temperature compensating member (12) in the direction of expansion of the piezoelectric element (1) by pressing at least a part of the side surfaces of the temperature compensating member (12) in the direction perpendicular to the direction of expansion; measuring at least one of a displacement amount of the contact member (5) and that of the displacement mechanism caused by the plastic deformation; and releasing the pressure against the temperature compensating member (12) when the measured displacement amount reaches a predetermined value.

Claim 11

A method for producing a displacement device comprising a piezoelectric element wherein the displacement of a column shape piezoelectric element (1) caused by applied voltage is applied by a displacement mechanism (8, 10), the method comprising: assembling frames (2, 4), the contact member (5), and the piezoelectric element (1) in a predetermined order; assembling a temperature compensating member (12) having temperature expansion characteristics reverse to those of the piezoelectric element (1) between the frame (2) and the piezoelectric element (1) and/or between the piezoelectric element (1) and the contact member (5); plastically deforming the temperature compensating member (12) in the direction of expansion of the piezoelectric element (1) by pressing at least a part of the side surfaces of the temperature compensating member (12) in the direction perpendicular to the direction of expansion; measuring at least one of a displacement amount of the contact member (5) and that of the displacement mechanism caused by the plastic deformation; and releasing the pressure against the temperature compensating member (12) when the measured displacement amount reaches a predetermined value.