Driving apparatus

Abstract

A driving apparatus comprises: an electro-mechanical conversion element; a driving shaft that reciprocates in response to an extension and contraction of the electro-mechanical conversion element; a driven member, frictionally engaged with the driving shaft, that moves along the driving shaft by reciprocating the driving shaft; and at least one shaft support portion each including a groove portion that accommodates therein the driving shaft and a spring member that biases the driving shaft accommodated in the groove portion to a direction of the groove portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view showing a driving apparatus according to an embodiment of the invention;

FIGS. 2A and 2B are diagrams showing waveforms of driving pulses which are impressed to a piezoelectric element shown in FIG. 1;

FIG. 3 is a circuit diagram showing a driving circuit of a control unit;

FIGS. 4A and 4B are diagrams showing waveforms of input signals which are inputted into the driving circuit shown in FIG. 3;

FIGS. 5A and 5B are diagrams showing waveforms of output signals which are outputted from the driving circuit shown in FIG. 3;

FIG. 6 is a perspective view showing a position detector of the driving apparatus shown in FIG. 1;

FIG. 7 is a diagram showing a modified example of a position detector of the driving apparatus shown in FIG. 1;

FIG. 8 is a sectional view of a driven member taken along the line VIII-VIII in FIG. 1;

FIG. 9 is a schematic perspective view showing a supporting state of an actuator shown in FIG. 1;

FIG. 10 is a sectional view of partitioning portions taken along the line α-α and the line β-β in FIG. 9; and

FIG. 11 is a sectional view showing a partitioning portion of a different form from the partitioning portion in FIG. 10.

Claims

1. A driving apparatus comprising: an electro-mechanical conversion element;a driving shaft that reciprocates in response to an extension and contraction of the electro-mechanical conversion element;a driven member, frictionally engaged with the driving shaft, that moves along the driving shaft by reciprocating the driving shaft; andat least one shaft support portion each including a groove portion that accommodates therein the driving shaft and a spring member that biases the driving shaft accommodated in the groove portion to a direction of the groove portion.

2. A driving apparatus as set forth in claim 1, wherein said at least one shaft support portion comprises two shaft support portions, andthe driving shaft is supported in a reciprocating fashion at both end portions of the driving shaft by the two shaft support portions

3. A driving apparatus as set forth in claim 1, wherein the groove portion comprises a groove having substantially a V-shape.