JP3721928B2 - Piezoelectric actuators, watches and portable devices - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a piezoelectric actuator, a timepiece including the piezoelectric actuator, and a portable device.
[0002]
[Prior art]
Since piezoelectric elements are excellent in conversion efficiency from electrical energy to mechanical energy and responsiveness, various piezoelectric actuators utilizing the piezoelectric effect of piezoelectric elements have been developed in recent years. This piezoelectric actuator is applied to fields such as a piezoelectric buzzer, an inkjet head of a printer, or an ultrasonic motor.
[0003]
[Problems to be solved by the invention]
Incidentally, a piezoelectric actuator using a piezoelectric element is often mounted on a small portable device or the like. In this case, if the user drops the portable device, the impact may be applied to the piezoelectric actuator and may be damaged. Conventionally, in the piezoelectric actuator, an effective improvement measure against such an impact caused by dropping or the like has not been proposed.
[0004]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a piezoelectric actuator capable of reducing damage caused by an impact such as dropping, a timepiece including the piezoelectric actuator, and a portable device. And Another object of the present invention is to increase the driving efficiency of a piezoelectric actuator.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, a piezoelectric actuator according to claim 1 of the present invention includes a support,
Are stacked and a pressure conductive element reinforcing portion, a diaphragm is that the plate surface shape a plate-like member having a longitudinal trapezoidal,
; And a support member projecting portion provided on the short side of the two sides of the end located in the longitudinal direction of the front Symbol diaphragm is vibratable supporting the vibrating plate so as to abut on the driven object,
The support member is a member having a fixed portion fixed to the support and an attachment portion attached to the diaphragm,
The attachment portion of the support member is attached to the vibration plate at a position that becomes a node when the vibration plate performs longitudinal vibration that expands and contracts in the longitudinal direction.
The said diaphragm, said at least said longitudinal vibration is generated I accompanied with vibration of the piezoelectric element is characterized and Turkey to drive the drive object by varying the position of the protrusion by the vertical vibration.
According to a second aspect of the present invention, in the piezoelectric actuator according to the first aspect, the longitudinal vibration and a direction perpendicular to the longitudinal direction are caused on the diaphragm in accordance with the vibration of the piezoelectric element. Bending vibration is generated, and the protrusion is moved along an elliptical orbit by the longitudinal vibration and bending vibration to drive the drive target.
According to a third aspect of the present invention, in the piezoelectric actuator according to the first aspect, the vicinity of the mounting portion of the support member is formed thicker than other portions of the support member. Yes.
[0006]
The piezoelectric actuator according to claim 4 is the piezoelectric actuator according to claim 1, in the prior SL diaphragm, the piezoelectric element in a portion other than the vicinity of the position where intake with portions of the front Symbol support member is attached There has been characterized by being stacked.
[0007]
The piezoelectric actuator according to claim 5 is the piezoelectric actuator according to claim 1, in the prior SL diaphragm, shock absorber provided near near the position where the intake mounting portion of the support member is attached It is characterized by being.
[0008]
The piezoelectric actuator according to claim 6 is the piezoelectric actuator according to claim 1, in the vicinity of the mounting portion before Symbol support member, is characterized in that the piezoelectric element is stacked.
[0009]
Further, the piezoelectric actuator according to claim 7, in the piezoelectric actuator according to claim 6, pressure-electronic device that will be stacked in the vicinity of the mounting portion before Symbol support member, Ru is the product layer on the vibrating plate pressure It is characterized by being integrally formed with the electric element.
[0010]
The piezoelectric actuator according to claim 8 is the piezoelectric actuator according to claim 1, before Symbol diaphragm is characterized in that its side shape is trapezoidal.
[0012]
The piezoelectric actuator according to claim 9 is the piezoelectric actuator according to any one of claims 1 to 7, wherein the support member has a front Symbol mounting portion has two, and the longitudinal direction of the diaphragm It is characterized by supporting from both sides in the vertical direction .
[0013]
A timepiece according to a tenth aspect includes the piezoelectric actuator according to any one of the first to ninth aspects.
A portable device according to an eleventh aspect includes the piezoelectric actuator according to any one of the first to ninth aspects.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
A. First embodiment A-1. Overall Configuration First, FIG. 1 is a plan view showing a main configuration of a calendar display mechanism of a wristwatch incorporating a piezoelectric actuator according to a first embodiment of the present invention. The piezoelectric actuator A1 is generally composed of a diaphragm 10 and a rotor 100 that expand and contract in an in-plane direction (a direction parallel to the drawing sheet). The rotor 100 is rotatably supported by the base plate 103 and is disposed at a position where it abuts on the diaphragm 10. When the outer peripheral surface of the rotor 100 is hit by vibration generated in the diaphragm 10, the rotor 100 rotates in the direction indicated by the arrow in the figure. It is designed to be driven.
[0015]
Next, the calendar display mechanism is connected to the piezoelectric actuator A1, and is driven by the driving force. The main part of the calendar display mechanism is mainly composed of a speed reduction wheel train for reducing the rotation of the rotor 100 and a ring-shaped date wheel 50. The speed reduction wheel train includes a date turning intermediate wheel 40 and a date turning wheel 60.
[0016]
Here, when the diaphragm 10 vibrates in the in-plane direction as described above, the rotor 100 in contact with the diaphragm 10 is rotated in the clockwise direction. The rotation of the rotor 100 is transmitted to the date indicator driving wheel 60 through the date indicator driving intermediate wheel 40, and the date indicator driving wheel 60 rotates the date indicator 50 in the clockwise direction.
[0017]
A-2. Next, the piezoelectric actuator A1 according to the present embodiment will be described. As shown in FIG. 2, the piezoelectric actuator A1 includes a trapezoidal diaphragm 10 formed long in the left-right direction in the figure, and a support member 11 that supports the diaphragm 10 on a ground plate 103 (see FIG. 1). ing.
[0018]
A protruding portion 36 made of stainless steel or the like is provided on the end portion 35 in the longitudinal direction of the vibration plate 10 so as to protrude toward the rotor 100, and the protruding portion 36 contacts the outer peripheral surface of the rotor 100. Yes. By providing such a protrusion 36, it is only necessary to perform an operation such as polishing on the protrusion 36 in order to maintain the state of the contact surface with the rotor 100. Becomes easy.
[0019]
Further, as shown in the figure, in the present embodiment, the protrusion 36 has a curved surface shape that protrudes toward the rotor 100 when viewed in a plan view. By forming the protrusions 36 that come into contact with the rotor 100 in a curved shape in this way, even when the positional relationship between the rotor 100 and the diaphragm 10 varies (due to dimensional variations or the like), the outer peripheral surface of the rotor 100 that is a curved surface The contact state with the curved protrusion 36 does not change much. Therefore, a stable contact state between the rotor 100 and the protrusion 36 can be maintained.
[0020]
One end portion (attachment portion) 37 of the L-shaped support member 11 is attached to a side portion in the longitudinal direction of the diaphragm 10. The other end portion (fixed portion) 38 of the support member 11 is supported on the base plate 103 (see FIG. 1) by screws 39. Under this configuration, the support member 11 supports the diaphragm 10 in a state in which the diaphragm 10 is urged toward the rotor 100 by its elastic force, thereby causing the protrusion 36 of the diaphragm 10 to abut against the side surface of the rotor 100. It has been. In addition, a fillet is formed at the end portion 37 of the support member 11, and is thicker in plan view than the other portions of the support member 11. Thereby, the strength of the attachment portion of the diaphragm 10 and the support member 11 is improved. Further, the end portion 37 of the support member 11 is attached to a position (on a line passing through the center of gravity G of the diaphragm 10 indicated by a broken line in the figure) that becomes a node when the diaphragm 10 vibrates longitudinally as described later. This prevents the vibration of the diaphragm 10 from being hindered.
[0021]
As shown in FIG. 3, the diaphragm 10 is between the two trapezoidal piezoelectric elements 30, 31 and has substantially the same shape as the piezoelectric elements 30, 31 and is thicker than the piezoelectric elements 30, 31. It has a laminated structure in which a reinforcing plate (reinforcing part) 32 such as a small stainless steel is arranged. By disposing the reinforcing plate 32 between the piezoelectric elements 30 and 31 in this way, damage to the diaphragm 10 due to overamplitude or external force of the diaphragm 10 can be reduced. Further, as the reinforcing plate 32, a member having a thickness smaller than that of the piezoelectric elements 30 and 31 is used so as not to disturb the vibration of the piezoelectric elements 30 and 31 as much as possible.
[0022]
Electrodes 33 are respectively disposed on the surfaces of the piezoelectric elements 30 and 31 disposed above and below. A voltage is supplied to the piezoelectric elements 30 and 31 via the electrode 33. Here, as the piezoelectric elements 30 and 31, lead zirconate titanate (PZT (trademark)), crystal, lithium niobate, barium titanate, lead titanate, lead metaniobate, polyvinylidene fluoride, lead zinc niobate ( (Pb (Zn1 / 3-Nb2 / 3) 03 1-x-Pb Ti 03 x) x varies depending on the composition. X = 0.09), lead scandium niobate ((Pb ((Sc1 / 2Nb1 / 2) 1- x Tix)) 03) x varies depending on the composition. Various types such as x = 0.09) can be used.
[0023]
When the AC voltage is applied to the piezoelectric elements 30 and 31 from the drive circuit via the electrode 33, the diaphragm 10 having such a configuration is vibrated by expansion and contraction of the piezoelectric elements 30 and 31. At that time, as shown in FIG. 4, the diaphragm 10 vibrates by longitudinal vibration that expands and contracts in the longitudinal direction, whereby the diaphragm 10 vibrates in the left-right direction of FIG. 2. When an AC voltage is applied to the piezoelectric elements 30 and 31 in this way to excite longitudinal vibration, bending vibration in the width direction is caused on the diaphragm 10 due to unbalanced weight balance of the diaphragm 10 or reaction force received from the rotor 100. Will be triggered. When such longitudinal vibration and bending vibration occur, the contact portion of the protrusion 36 of the diaphragm 10 with the outer peripheral surface of the rotor 100 moves along an elliptical orbit as shown in FIG. The rotor 100 is driven to rotate as the projection 36 moves.
[0024]
In the present embodiment, the diaphragm 10 is trapezoidal, so that the unbalanced weight balance is larger than that of the rectangular shape, thereby increasing the induced bending vibration. Moreover, since the diaphragm 10 has a shape in which the protruding portion 36 side becomes narrow, the rigidity on the protruding portion 36 side is lowered. Accordingly, a larger flexural vibration can be obtained on the protruding portion 36 side of the diaphragm 10. By adopting the trapezoidal diaphragm 10 in this manner, the protrusion 36 moves along a larger elliptical orbit, and the rotor 100 can be driven more efficiently.
[0025]
A-3. Operation of Piezoelectric Actuator Next, the operation of the piezoelectric actuator A1 having the above configuration will be described. First, when a voltage is applied to the diaphragm 10 from a drive circuit (not shown), the diaphragm 10 vibrates due to expansion and contraction of the piezoelectric elements 30 and 31, and the diaphragm 10 is in contact with the rotor 100 as described above. Moves along an elliptical orbit. The rotor 100 is rotated in the direction of the arrow in FIG. When the rotor 100 is rotated , the date indicator 50 is rotated via the date turning intermediate wheel 40 (see FIG. 1), and the displayed day and day are switched.
[0026]
When the protrusion 36 is moved along the elliptical orbit as described above, the shape of the diaphragm 10 preferably has impedance characteristics as shown in FIG. The impedance change characteristic shown in FIG. 6 is such that the resonance frequency of bending vibration is slightly higher than the resonance frequency of longitudinal vibration. When the diaphragm 10 having a shape that slightly increases the resonance frequency of the bending vibration as compared with the resonance frequency of the longitudinal vibration as described above and the diaphragm 10 is driven at a frequency between the two resonance frequencies, the diaphragm 10 Both the generated longitudinal vibration and bending vibration can be increased, and the protrusion 36 can be moved along a larger elliptical orbit.
[0027]
In the present embodiment, by adopting the drive frequency and the shape of the diaphragm 10 as described above, the displacement of the protruding portion 36 of the diaphragm 10 is increased to improve the drive efficiency. In addition to this, in this embodiment, the impact resistance of the piezoelectric actuator A1 is improved by using the support member 11 on which the above fillet is formed and making the diaphragm 10 trapezoidal. Specifically, when the wristwatch is dropped or the like and an impact is applied, a large amount of force acts on the end portion 37 that is a joint portion between the support member 11 and the diaphragm 10, and this portion is most likely to be damaged. . In the present embodiment, in consideration of this point, by forming a fillet in the vicinity of the end portion 37 as described above, the strength in the vicinity of the coupling portion between the support member 11 and the diaphragm 10 is increased to improve the impact resistance. ing. Further, when the wristwatch falls, it can be considered that a large force acts on the piezoelectric actuator A1 in the direction perpendicular to the paper surface of FIG. Even when such a force is applied to the diaphragm 10, the diaphragm 10 is shaped like a trapezoid, that is, a shape in which the tip end side becomes narrow as in the present embodiment, so that the vibration is generated by the impact force transmitted from the support member 11. The stress applied to the plate 10 is made more uniform than in the case of a rectangular shape, and the shock resistance against dropping or the like can be improved.
[0028]
B. Second Embodiment Next, a piezoelectric actuator according to a second embodiment of the present invention will be described with reference to FIGS. The difference between the piezoelectric actuator A2 according to the second embodiment and the piezoelectric actuator A1 according to the first embodiment is that the shape of the piezoelectric element laminated on the reinforcing plate 32 in the diaphragm 10 is different. Specifically, as shown in FIG. 7, a piezoelectric element (similarly, a piezoelectric element laminated on the back side of the paper) is not laminated in the vicinity of the portion to which the end portion 37 of the diaphragm 10 is attached. . That is, the diaphragm 10 according to the second embodiment has a structure in which piezoelectric elements 30a and 31a each having a shape in which a part of a trapezoid is cut are stacked on top and bottom of a trapezoidal reinforcing plate 32 as shown in FIG. Yes. In the drawing, the electrodes provided on the piezoelectric elements 30a and 31a are omitted, but the electrodes have the same shape as the piezoelectric elements 30a and 31a.
[0029]
Also in the piezoelectric actuator A2 according to the second embodiment, the rotor 100 can be driven with excellent driving efficiency as in the first embodiment described above. Since the trapezoidal diaphragm 10 is used as in the first embodiment, a force in a direction perpendicular to the plane to which the diaphragm 10 belongs (perpendicular to the plane of FIG. 7) is applied due to dropping or the like. Impact resistance can be improved.
[0030]
In the piezoelectric actuator A2, the piezoelectric elements 30a and 31a are not attached in the vicinity of the portion where the support member 11 is attached. This is because when the impact of external force or the like is applied to the piezoelectric actuator A2, it is considered that the largest force acts in the vicinity of the coupling portion of the diaphragm 10 with the support member 11, and this large force acts. The piezoelectric element with low rigidity is not provided in the portion. For example, when an impact or the like is applied to the piezoelectric actuator and a large force is applied in the vicinity of the portion where the diaphragm 10 is coupled to the support member 11, there is a high possibility that the piezoelectric element in the vicinity is peeled off or damaged. If the piezoelectric element is partially damaged in this way, the piezoelectric actuator will operate with characteristics different from those originally designed. On the other hand, in the piezoelectric actuator A2 according to the second embodiment, a piezoelectric element is not provided in the vicinity of the coupling portion with the support member 11 where a large force is likely to act, and desired characteristics can be exhibited in such a configuration. In addition, the drive frequency is designed. Therefore, it is possible to suppress changes in actuator characteristics due to impact or the like.
[0031]
C. Third Embodiment Next, a piezoelectric actuator according to a third embodiment of the present invention will be described with reference to FIGS. The difference between the piezoelectric actuator A3 according to the third embodiment and the piezoelectric actuator A1 according to the first embodiment is that a shock absorbing film 250 is provided on the diaphragm 10 of the piezoelectric actuator A3. Specifically, as shown in FIG. 9, an impact absorbing film 250 is provided in the vicinity of the coupling portion of the diaphragm 10 with the support member 11. As shown in FIG. 10, the shock absorbing film 250 is formed on the electrodes (not shown) of the piezoelectric elements 30a and 31a, so that the shock applied to the diaphragm 10 can be absorbed. As such a shock absorbing film 250, it is preferable to use a film having a low elastic modulus such as an adhesive or silicon rubber.
[0032]
Also in the piezoelectric actuator A3 according to the third embodiment, the rotor 100 can be driven with excellent driving efficiency as in the first embodiment described above. Further, since the trapezoidal diaphragm 10 is used as in the first embodiment, a force in a direction perpendicular to the plane to which the diaphragm 10 belongs (perpendicular direction in FIG. 9) is applied due to dropping or the like. Impact resistance can be improved.
[0033]
In the piezoelectric actuator A3, the shock absorbing film 250 is provided in the vicinity of the coupling portion of the diaphragm 10 with the support member 11. This is because when the impact such as an external force is applied to the piezoelectric actuator A3, it is considered that the largest force acts in the vicinity of the coupling portion with the support member 11 of the diaphragm 10, and this force acts on the piezoelectric actuator A3. By providing the impact absorbing film 250 having a low elastic modulus in the portion, it is possible to absorb this force and reduce damage to the diaphragm 10 and the like. Of course, it is conceivable to provide a shock-absorbing layer 250 on the diaphragm 10 all face, considering the vibration characteristics of the vibration plate 10 in order to obtain a high drive efficiency, shock-absorbing layer 250 who does not form is preferred. In the present embodiment, in consideration of both vibration characteristics and impact resistance, the impact absorbing film 250 is provided only in a portion where a large force is likely to be applied, and the impact resistance is hardly reduced. Has improved.
[0034]
D. Fourth Embodiment Next, a piezoelectric actuator according to a fourth embodiment of the present invention will be described with reference to FIG. The piezoelectric actuator according to the fourth embodiment has the same planar configuration as that of the first embodiment (see FIG. 2), and the difference between them is that the side surface shape of the diaphragm 10 is different. More specifically, the side surface shape (see FIG. 3) of the diaphragm 10 in the first embodiment is rectangular, whereas the diaphragm 10 of the piezoelectric actuator according to the fourth embodiment is thin on the protruding portion 36 side. It is made into a trapezoid shape.
[0035]
In the piezoelectric actuator according to the fourth embodiment, the rotor 100 can be driven with excellent driving efficiency as in the first embodiment described above. Further, since the trapezoidal diaphragm 10 is used as in the first embodiment, it is possible to improve the impact resistance when a force in a direction perpendicular to the plane to which the diaphragm 10 belongs is applied due to dropping or the like. it can.
[0036]
Moreover, since the side surface shape of the diaphragm 10 is a trapezoidal shape, even when a force is applied to the diaphragm 10 from the side surface direction, the stress applied to the diaphragm 10 is made more uniform than that of the rectangular shape of the side surface. The impact resistance against the force from the side surface direction can be improved.
[0037]
E. Fifth Embodiment Next, a piezoelectric actuator according to a fifth embodiment of the present invention will be described with reference to FIGS. The difference between the piezoelectric actuator A5 according to the fifth embodiment and the piezoelectric actuator A1 according to the first embodiment is that the shape of the piezoelectric element laminated on the reinforcing plate 32 in the diaphragm 10 is different. Specifically, as shown in FIG. 12, in addition to the trapezoidal reinforcing plate, a piezoelectric element (same as the piezoelectric element laminated on the back side of the paper) is also laminated in the vicinity of the end portion 37 of the support member 11. It has become. That is, the diaphragm 10 according to the fifth embodiment has a structure in which piezoelectric elements 30b and 31b each having a portion 300 extending from a part of a trapezoid are stacked on top and bottom of a trapezoidal reinforcing plate 32 as shown in FIG. It has become. In the figure, the electrodes provided on the piezoelectric elements 30b and 31b are omitted, but the electrodes have a trapezoidal shape as in the first embodiment. Therefore, in this embodiment, no voltage is applied to the portion 300 of the piezoelectric elements 30b and 31b, and the portion 300 is not used to excite vibration.
[0038]
Also in the piezoelectric actuator A5 according to the fifth embodiment, the rotor 100 can be driven with excellent driving efficiency as in the first embodiment described above. In addition, since the trapezoidal diaphragm 10 is used as in the first embodiment, a force in a direction perpendicular to the plane to which the diaphragm 10 belongs (perpendicular to the paper in FIG. 12) is applied due to dropping or the like. Impact resistance can be improved.
[0039]
Further, in this piezoelectric actuator A5, since the piezoelectric element is also laminated in the vicinity of the end portion 37 of the support member 11, the thickness in the vicinity of the end portion 37 of the support member 11 is increased by the thickness of the piezoelectric element. Accordingly, the rigidity in the vicinity of the end portion 37 of the support member 11 is improved. The rigidity in the vicinity of the end portion 37 of the support member 11 is improved in the vicinity of the end portion 37 that is a portion where the support member 11 is coupled to the diaphragm 10 when an impact such as an external force is applied to the piezoelectric actuator A5. In this way, the impact resistance of the piezoelectric actuator A5 is improved.
[0040]
In addition, in order to improve the impact resistance as described above, the piezoelectric actuator A5 is simply formed by laminating the piezoelectric elements 30b and 31b having the shape of the portion 300, and a process of newly providing a reinforcing member or the like. There is no need. Therefore, impact resistance can be improved without complicating the manufacturing process.
[0041]
F. Modifications The present invention is not limited to the various embodiments described above, and various modifications as described below are possible.
[0043]
(Modification 1 )
Further, in each of the embodiments described above, the support member 11 supports one side of the diaphragm 10, but the support member 11 is attached to both sides of the diaphragm 10 as shown in FIG. May be supported.
[0044]
(Modification 2 )
Furthermore, the piezoelectric actuator according to each of the above-described embodiments can be used by being mounted on a portable device other than a battery-driven timepiece, in addition to being mounted on the calendar display mechanism of the timepiece as described above.
[0045]
【The invention's effect】
As described above, according to the present invention, the plate surface shape of the diaphragm is trapezoidal, so that the unbalance of the weight balance can be increased compared to the plate surface shape having a rectangular shape. The vibration generated in the diaphragm can be made larger. In addition, since the position where the diaphragm is supported is a position that becomes a node when the diaphragm vibrates longitudinally, the support member prevents the longitudinal vibration generated in the diaphragm as much as possible. As described above, according to the present invention, fluctuations in the protrusions of the diaphragm can be made larger, and less energy is required to generate vibrations in the diaphragm. Can be increased.
Further, according to the present invention, it is possible to reduce damage caused by an impact such as dropping.
[Brief description of the drawings]
FIG. 1 is a plan view showing a main configuration of a calendar display mechanism of a wristwatch provided with a piezoelectric actuator according to a first embodiment of the present invention.
FIG. 2 is a plan view showing an overall configuration of the piezoelectric actuator.
FIG. 3 is a side sectional view showing a diaphragm that is a component of the piezoelectric actuator.
FIG. 4 is a diagram illustrating a state in which the diaphragm vibrates longitudinally.
FIG. 5 is a diagram for explaining a trajectory of a protrusion provided on one end side of the diaphragm during vibration of the diaphragm.
FIG. 6 is a graph showing an example of the relationship between the vibration frequency and impedance of the diaphragm.
FIG. 7 is a plan view showing an overall configuration of a piezoelectric actuator according to a second embodiment of the present invention.
FIG. 8 is an exploded perspective view showing a configuration of a diaphragm that is a component of the piezoelectric actuator according to the second embodiment.
FIG. 9 is a plan view showing an overall configuration of a piezoelectric actuator according to a third embodiment of the present invention.
FIG. 10 is an exploded perspective view showing a configuration of a diaphragm that is a component of the piezoelectric actuator according to a third embodiment.
FIG. 11 is a side view showing a diaphragm that is a component of a piezoelectric actuator according to a fourth embodiment of the present invention.
FIG. 12 is a plan view showing an overall configuration of a piezoelectric actuator according to a fifth embodiment of the present invention.
FIG. 13 is an exploded perspective view showing a configuration of a diaphragm that is a component of the piezoelectric actuator according to a fifth embodiment.
FIG. 14 is a plan view showing an overall configuration of a modified example of the piezoelectric actuator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Diaphragm, 11 ... Support member, 30, 30a, 30b, 31, 31a, 31b ... Piezoelectric element, 35 ... End part, 36 ... Projection part, 37 ... End part (attachment part), 40 …… Day-turning intermediate wheel, 50 …… Date wheel, 60 …… Day-turning wheel, 100 …… Rotor (drive target), 103 …… Ground plate (support) 250 …… Shock absorbing film, A1, A2, A3 , A5: Piezoelectric actuator

Claims (11)

A support;
Are stacked and a pressure conductive element reinforcing portion, a diaphragm is that the plate surface shape a plate-like member having a longitudinal trapezoidal,
; And a support member projecting portion provided on the short side of the two sides of the end located in the longitudinal direction of the front Symbol diaphragm is vibratable supporting the vibrating plate so as to abut on the driven object,
The support member is a member having a fixed portion fixed to the support and an attachment portion attached to the diaphragm,
The attachment portion of the support member is attached to the vibration plate at a position that becomes a node when the vibration plate performs longitudinal vibration that expands and contracts in the longitudinal direction.
The said diaphragm, said at least said longitudinal vibration is generated I accompanied with vibration of the piezoelectric element, you drive the driven object by varying the position of the protrusion by the vertical vibration
The piezoelectric actuator according to claim and this. Along with the vibration of the piezoelectric element, the longitudinal vibration and a bending vibration in a direction perpendicular to the longitudinal direction are generated in the vibration plate, and the longitudinal vibration and the bending vibration cause the protrusion to move along the elliptical orbit. Move to drive the drive object
The piezoelectric actuator according to claim 1. Vicinity of the mounting portion before Symbol support member, a piezoelectric actuator according to claim 1, characterized in that it is formed thicker than other portions of the support member. The front Symbol diaphragm, a piezoelectric actuator according to claim 1, wherein a portion other than the vicinity of the position taken with portions of the front Symbol support member is attached piezoelectric element is characterized in that it is laminated. The front Symbol diaphragm, a piezoelectric actuator according to claim 1, characterized in that shock-absorbing material is provided in the near vicinity of a position taken with portions of the support member is attached. In the vicinity of the mounting portion before Symbol support member, a piezoelectric actuator according to claim 1, characterized in that the piezoelectric element is stacked. The pressure-electronic device that will be stacked in the vicinity of the mounting portion have contact to the support member, according to claim 6, characterized in that said is formed by integral molding with pressure conductive elements that will be the product layer on the vibrating plate Piezoelectric actuator. Before SL diaphragm, a piezoelectric actuator according to claim 1, characterized in that the side surface shape is trapezoidal. The support member, the front Symbol mounting section has two piezoelectric actuator according to any one of claims 1 to 7 to the diaphragm, characterized in that the support from both sides in the direction perpendicular to a longitudinal direction. Claims 1 to watch characterized by having a piezoelectric actuator according to any one of 9. Portable device characterized by having a piezoelectric actuator according to any one of claims 1 to 9.

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