WO2020110654A1 - Actuator and tactile presentation device - Google Patents

Abstract

Provided is an actuator comprising a piezoelectric element and a vibration plate. The piezoelectric element has a bonding face. The vibration plate is bonded to the bonding face of the piezoelectric element and vibrates according to deformation or displacement of the piezoelectric element. The center of the bonding face of the piezoelectric element is bonded so as to be positioned inside an area in which a transmission unit is disposed on the vibration plate.

Description

Actuator and tactile presentation device Cross-reference of related applications

This application claims the priority of Japanese Patent Application No. 2018-222017, which was filed as a patent in Japan on November 28, 2018, and the entire disclosure of the previous application is incorporated herein by reference.

The present disclosure relates to an actuator and a tactile sensation providing device.

Conventionally, a structure in which an actuator that generates vibration is arranged in a touch sensor or the like is known. The actuator may be a piezoelectric element such as a unimorph. For example, Patent Document 1 discloses a structure in which an actuator that generates vibration is arranged on a vibration target (hereinafter, also simply referred to as a vibration target) such as a touch sensor. In such a structure, the actuator provides a tactile sensation to the fingertip of the user who touches the vibration target by vibrating the vibration target.

JP, 2017-175874, A

An actuator according to an embodiment includes a piezoelectric element and a vibration plate.
The piezoelectric element has a bonding surface.
The vibrating plate is joined to the joint surface of the piezoelectric element, and vibrates according to deformation or displacement of the piezoelectric element.
The center of the bonding surface of the piezoelectric element is bonded so that the center of the bonding surface is located in a region in the vibration plate where the vibration transmitting unit is arranged.

A tactile sensation providing apparatus according to an embodiment includes the actuator described above, a vibration target, and a vibration transmission unit.
The vibration of the diaphragm is transmitted to the vibrating object and presents a tactile sensation to the user.
The vibration transmission unit transmits the vibration of the diaphragm to the vibration target.

It is an important section sectional view showing the example of composition of the tactile sense presentation device concerning one embodiment. It is a perspective view which shows the structural example of an actuator. It is an exploded perspective view explaining composition of an actuator. It is a figure which shows an example of the locator which positions a piezoelectric element. It is a figure which shows an example of the locator which positions a piezoelectric element. It is a figure which shows an example of the locator which positions a piezoelectric element. It is a figure which shows an example of the locator which positions a piezoelectric element. It is an example of a functional block of the tactile sensation providing apparatus according to an embodiment. It is an important section sectional view showing the example of composition of the tactile sense presentation device concerning one embodiment.

▽ In order to present a sufficient tactile sensation to the user, it is necessary to vibrate the vibrating object well. For that purpose, it is required that the vibration generated by the actuator be efficiently transmitted to the vibration target. An object of the present disclosure is to provide an actuator and a tactile sensation providing apparatus that efficiently generate good vibration. According to the actuator and the tactile sensation providing apparatus according to the embodiment, good vibration can be efficiently generated.

Hereinafter, an actuator and a tactile sensation providing apparatus according to an embodiment will be described with reference to the drawings. The actuator according to this embodiment can be used in various devices. The tactile sensation providing apparatus according to the present embodiment may be a car navigation system, or an on-vehicle device such as a steering wheel or a power window switch. The tactile sensation providing device may be a mobile phone, a smartphone, a tablet PC (Personal Computer), a notebook PC, or the like. The tactile sensation providing device is not limited to these, and may be various electronic devices such as desktop PCs, home electric appliances, industrial equipment (FA (Factory Automation) equipment), and dedicated terminals. The drawings used in the following description are schematic, and the dimensional ratios and the like in the drawings do not always match the actual ones.

FIG. 1 is a cross-sectional view of essential parts showing a configuration example of a tactile sensation providing apparatus 1 according to an embodiment. As shown in FIG. 1, the tactile sensation providing apparatus 1 according to the present embodiment includes an actuator 10, a vibration transmission unit 15, a housing 20, and a vibration target 30.

The actuator 10 includes a piezoelectric element 11 and a diaphragm 12. Further, the actuator 10 may include the support portion 13. The actuator 10 is joined to the housing 20 via the support portion 13. The vibration target 30 is joined to the actuator 10 via the vibration transmission unit 15.

FIG. 2 is a perspective view showing a configuration example of the actuator 10. FIG. 2 shows a state in which the actuator 10 shown in FIG. 1 is turned upside down. FIG. 3 shows a state in which the actuator 10 shown in FIG. 2 is disassembled. Hereinafter, each part of the actuator 10 will be described with reference to FIGS. 1 to 3.

The piezoelectric element 11 expands and contracts in various patterns in the longitudinal direction according to the applied voltage signal. The piezoelectric element 11 may be a piezoelectric film or a piezoelectric ceramic. Piezoelectric ceramics can generate vibrations with greater vibrational energy than piezoelectric films.

The piezoelectric element 11 may be replaced with a magnetostrictive element. The magnetostrictive element expands and contracts according to the applied magnetic field. When a magnetostrictive element is used, a coil that converts an applied voltage signal into a magnetic field is also used.

The piezoelectric element 11 may have a rectangular shape, for example. More specifically, the piezoelectric element 11 may have a rectangular parallelepiped shape. As shown in FIGS. 2 and 3, the piezoelectric element 11 may have a thin strip shape. That is, the size of the piezoelectric element 11 in the longitudinal direction (X axis direction) and the lateral direction (Y axis direction) may be larger than the size of the piezoelectric element 11 in the thickness direction (Z axis direction).

The diaphragm 12 is a rectangular plate-shaped member having a predetermined thickness. The diaphragm 12 is, for example, a thin plate having elasticity. The diaphragm 12 is made of metal, resin, or a composite material of metal and resin or the like. The diaphragm 12 may be a thin metal plate (also referred to as a shim plate). Hereinafter, the surface facing the housing 20 side is referred to as a first surface 12a. The surface facing the vibration target 30 side is referred to as a second surface 12b. That is, the diaphragm 12 may have the first surface 12a and the second surface 12b opposite to the first surface 12a.

The piezoelectric element 11 is provided on the first surface 12 a of the diaphragm 12. The piezoelectric element 11 is provided so that the longitudinal direction of the piezoelectric element 11 coincides with the longitudinal direction of the diaphragm 12. The vibration transmission unit 15 is arranged on the second surface 12b of the diaphragm 12. At least one of the piezoelectric element 11 and the vibration transmission unit 15 may be bonded to the vibration plate 12 by a method such as bonding.

The structure in which the piezoelectric element 11 is provided on the first surface 12a of the diaphragm 12 is a so-called monomorph. In the monomorph, expansion and contraction displacement of the piezoelectric element 11 causes bending vibration of the diaphragm 12. When only one end of the diaphragm 12 is supported by the housing 20, the amplitude of the other end of the diaphragm 12 in the normal direction (Z-axis direction) of the first surface 12a becomes maximum. To vibrate. As shown in FIG. 1, when both ends of the diaphragm 12 are supported by the housing 20, the amplitude in the normal direction (Z-axis direction) of the first surface 12a near the center of the diaphragm 12 is maximum. Vibrate to become.

The support 13 may be made of a resin material. The resin material may be a rubber material such as silicone rubber or a sponge material such as a hard sponge. The support portion 13 is configured to elastically deform so as to reduce the damping of the vibration of the diaphragm 12. As shown in FIG. 1, support portions 13 are provided at both ends of the diaphragm 12 in the longitudinal direction. The support portion 13 maintains a clearance between the piezoelectric element 11 and the housing 20 so that the piezoelectric element 11 does not collide with the housing 20 even if the vibration plate 12 vibrates according to the deformation or displacement of the piezoelectric element 11. .. The support portion 13 may be a thin plate having elasticity, like the vibration plate 12, for example. The support 13 may be made of the same material as the diaphragm 12, or may be made of a different material. As described above, when both ends of the vibrating plate 12 are supported, the vibrating plate 12 vibrates according to the displacement of the piezoelectric element 11 so that the amplitude near the center of the vibrating plate 12 becomes maximum.

As shown in FIG. 1, one end of the support portion 13 is connected to the diaphragm 12. More specifically, one end of the support 13 is connected to the first surface 12a of the diaphragm 12. The other end of the support portion 13 is connected to the housing 20. The support part 13 is fixed to the housing 20 by, for example, screwing or bonding.

The vibration transmission unit 15 is made of, for example, a rubber material or the like. The vibration transmitting portion 15 is not limited to a rubber material or the like, and may be made of another material such as metal. The vibration transmitting unit 15 is arranged on the second surface 12b side of the diaphragm 12. The vibration transmitting unit 15 may be joined to the diaphragm 12 using a method such as bonding. The vibration transmitting portion 15 is provided near the center on the second surface 12b side. The position where the vibration transmitting unit 15 is provided is not limited to the vicinity of the center. The vibration transmitting unit 15 may be provided in a portion of the diaphragm 12 where the vibration has the maximum amplitude. The vibration target 30 is joined to the vibration transmitting unit 15 by using, for example, a method such as adhesion.

The vibration transmission unit 15 has a large elastic coefficient in the vibration direction of the vibration plate 12, that is, in the normal direction (Z-axis direction) of the first surface 12a so that the vibration of the vibration plate 12 is efficiently transmitted to the vibration target 30. You may have. On the other hand, the vibration transmission unit 15 may have a small elastic coefficient in a direction (X-axis direction or Y-axis direction) parallel to the first surface 12a of the diaphragm 12. By doing so, the possibility of breakage of the tactile sensation providing apparatus 1 due to an external force can be reduced. The elastic coefficient is a constant indicating the relationship between the external force applied to the member and the displacement amount of the member, and the product of the displacement amount and the elastic coefficient is the external force. That is, the displacement amount with respect to the same external force increases as the elastic coefficient decreases.

The actuator 10 is joined to the housing 20 by the support portion 13. The housing 20 has a larger mass and higher rigidity than the actuator 10. Therefore, in this embodiment, the housing 20 is regarded as a rigid body. The vibration target 30 may be, for example, a touch sensor 50 (see FIG. 8) or a switch provided in the device. The vibration transmission unit 15 joins the actuator 10 to the vibration target 30. As described above, when the housing 20 is regarded as a rigid body, the vibration generated by the actuator 10 is mainly transmitted to the vibration target 30. Therefore, the vibration target 30 can present a tactile sensation to the touched user.

Next, the position where the piezoelectric element 11 is bonded to the diaphragm 12 in the present embodiment will be further described.

As shown in FIGS. 2 and 3, the piezoelectric element 11 is bonded to the diaphragm 12. The piezoelectric element 11 has a joint surface 11 a that is joined to the diaphragm 12. As shown in FIG. 3, the bonding surface 11 a of the piezoelectric element 11 is bonded to the first surface 12 a of the diaphragm 12. As shown in FIG. 3, the bonding surface 11a of the piezoelectric element 11 is arranged at the position of the region R1 on the first surface 12a of the diaphragm 12. Further, as shown in FIG. 3, the vibration transmission portion 15 is arranged on the second surface 12b of the vibration plate 12. The arrangement surface 15a of the vibration transmitting unit 15 is arranged at the position of the region R2 on the second surface 12b of the diaphragm 12.

In the present embodiment, when the piezoelectric element 11 is bonded to the vibration plate 12, the center of the bonding surface 11a of the piezoelectric element 11 is positioned inside the region R2 where the vibration transmission portion 15 is arranged in the vibration plate 12. Position. Here, the center of the joint surface 11a of the piezoelectric element 11 may be, for example, the center C1 of the joint surface 11a of the piezoelectric element 11 shown in FIG. Here, the center C1 may be, for example, a point that bisects a two-dot chain line M1 that represents the length of the piezoelectric element 11 in the longitudinal direction (X-axis direction). Thus, at the position corresponding to the center of the piezoelectric element 11 in the longitudinal direction, the vibration (displacement in the Z-axis direction) of the piezoelectric element 11 becomes maximum. Further, the center C1 may be, for example, an intersection of a two-dot chain line M2 indicating the length of the piezoelectric element 11 in the lateral direction (Y-axis direction) and the above-mentioned two-dot chain line M1. As described above, in the present embodiment, the center C1 of the bonding surface 11a of the piezoelectric element 11 is bonded so as to be located in the region R2 where the vibration transmitting portion 15 is arranged in the vibration plate 12.

In the present embodiment, the center C1 of the bonding surface 11a of the piezoelectric element 11 may be located at the center of the region R2 as the position in the region R2 where the vibration transmitting unit 15 is arranged in the diaphragm 12. The center of the region R2 may be, for example, the point C2 in FIG. That is, in the present embodiment, the center C1 of the bonding surface 11a of the piezoelectric element 11 may be bonded so as to be located at the position of the center C2 of the region R2 in the vibration plate 12 where the vibration transmitting unit 15 is arranged. The center C2 of the region R2 may be a point located at the center of gravity of the region R2 where the vibration transmitting unit 15 is arranged in the diaphragm 12. When the vibration transmitting portion 15 is arranged on the diaphragm 12, the position of the center C2 of the region R2 becomes the same as the position of the center of gravity C3 of the arrangement surface 15a of the vibration transmitting portion 15. Therefore, the center C2 of the region R2 may be a position corresponding to the center of gravity C3 of the arrangement surface 15a of the vibration transmission unit 15.

As described above, in the present embodiment, the vibration transmission unit 15 is arranged on the diaphragm 12 with the center of gravity C3 corresponding to the position of the center C2. Further, in the present embodiment, the piezoelectric element 11 is bonded to the vibration plate 12 with the center C1 corresponding to the position within the region R2 (or the center C2). That is, in the present embodiment, the center C1 of the joint surface 11a of the piezoelectric element 11 is positioned within the region R2 (or the center (center of gravity) of the region R2) in the vibration plate 12 where the vibration transmitting portion 15 is arranged. To be joined.

According to such a configuration, the vibration transmission section 15 is arranged at a position where the vibration of the piezoelectric element 11 (displacement in the Z-axis direction) is maximized. Therefore, according to the tactile sensation providing apparatus according to the present embodiment, the vibration generated by the actuator 10 is efficiently transmitted to the vibration target 30. Therefore, according to the actuator 10 of the present embodiment, it is possible to vibrate the vibration target 30 satisfactorily and present a sufficient tactile sensation to the user. Therefore, the actuator 10 according to the present embodiment can efficiently generate good vibration.

Further, the tactile sensation providing apparatus according to the present embodiment includes the actuator 10, the vibration target 30, and the vibration transmission unit 15 described above. The vibration of the diaphragm 12 is transmitted to the vibration target 30, and the tactile sensation is presented to the user. The vibration transmission unit 15 transmits the vibration of the diaphragm 12 to the vibration target 30. According to the tactile sensation providing apparatus according to the present embodiment, the vibration generated by the actuator 10 is efficiently transmitted to the vibration target 30. Therefore, according to the tactile sensation providing apparatus according to the present embodiment, it is possible to satisfactorily vibrate the vibration target 30 and present a sufficient tactile sensation to the user. Therefore, according to the tactile sensation providing apparatus according to the present embodiment, good vibration can be efficiently generated.

Further, according to the tactile sensation providing apparatus according to the present embodiment, the piezoelectric element 11 and the vibration transmitting unit 15 are arranged at structurally appropriate positions with respect to the diaphragm 12. Therefore, the tactile sensation providing apparatus according to the present embodiment has structurally appropriate strength. Therefore, when the user presses the vibration target 30, the piezoelectric element 11 and/or the diaphragm 12 are less likely to be damaged.

Next, the locator provided on the diaphragm 12 in the present embodiment will be further described.

As described above, the piezoelectric element 11 may be bonded to the diaphragm 12 by a method such as bonding. Further, the vibration transmitting portion 15 may also be joined to the diaphragm 12 by a method such as adhesion. For example, it is assumed that the vibration transmitting unit 15 is arranged on the diaphragm 12 with the center of gravity C3 appropriately corresponding to the position of the center C2. Even in such a case, unless the center C1 of the piezoelectric element 11 is properly joined to the position within the region R2 of the vibration plate 12 (or the center C2), the vibration generated by the actuator 10 will be the vibration target 30. Is not transmitted efficiently. However, it is assumed that it is not always easy to bond the piezoelectric element 11 to the appropriate position of the diaphragm 12. Therefore, in the present embodiment, the diaphragm 12 may include a locator for positioning the piezoelectric element 11.

FIG. 4 is a diagram showing an example of a locator for positioning the piezoelectric element 11 in the embodiment.

As shown in FIG. 4, the diaphragm 12A may include a recessed locator L1 for positioning the piezoelectric element 11 on the first surface 12a. Providing the groove-like recessed portion like the locator L1 makes it possible to easily and reliably perform appropriate positioning when the piezoelectric element 11 is bonded to the first surface 12a of the diaphragm 12A.

Also, by having a groove-shaped recess like the locator L1, an appropriate amount of adhesive can be easily applied when the piezoelectric element 11 is bonded to the diaphragm 12A. For example, the piezoelectric element 11 may be bonded after the adhesive is applied to such an extent that the groove-shaped concave portion like the locator L1 of the diaphragm 12A is just filled. With such joining, an appropriate amount of adhesive is uniformly applied to the bonding surface between the piezoelectric element 11 and the vibration plate 12.

When forming a groove-shaped recess like the locator L1, a relatively shallow recess may be formed so that the diaphragm 12 maintains sufficient strength. For example, when the thickness of the diaphragm 12 (size in the Z-axis direction) is about 1 mm and the thickness of the piezoelectric element 11 (size in the Z-axis direction) is about 0.7 mm, the depth of the locator L1 (Z-axis). The size in the direction) may be about 0.3 to 0.4 mm.

Thus, the diaphragm 12 may include a locator for positioning the joint surface 11a of the piezoelectric element 11. For example, the diaphragm 12 may use the recess L1 for positioning the joint surface 11a of the piezoelectric element 11 as a locator. With such a locator, the piezoelectric element 11 can be easily bonded to an appropriate position on the diaphragm 12.

FIG. 5 is a diagram showing another example of the locator for positioning the piezoelectric element 11 in the embodiment.

As shown in FIG. 5, the vibrating plate 12B may include convex-shaped locators L2 to L5 for positioning the piezoelectric element 11 on the first surface 12a. Providing, for example, a protrusion formed in a protrusion shape like the locators L2 to L5, it is possible to easily and reliably perform proper positioning when the piezoelectric element 11 is bonded to the first surface 12a of the vibration plate 12B. You can As an example in which the diaphragm 12B shown in FIG. 5 is simplified, for example, only the locators L2 and L5 or only the locators L3 and L4 may be provided.

FIG. 6 is a diagram showing another example of the locator for positioning the piezoelectric element 11 in the embodiment.

As shown in FIG. 6, the vibrating plate 12C may include locators L6 and L7 having a convex shape for positioning the piezoelectric element 11 on the first surface 12a. Providing, for example, a protrusion formed in a protrusion shape like the locators L6 and L7, it is possible to easily and reliably perform appropriate positioning when the piezoelectric element 11 is bonded to the first surface 12a of the diaphragm 12C. You can As an example in which the diaphragm 12C shown in FIG. 6 is simplified, for example, only one of the locators L6 and L7 may be provided.

As described above, the vibration plate 12 may use a convex portion (for example, L2 to L5, or L6 and L7) for positioning the bonding surface 11a of the piezoelectric element 11 as a locator. With such a locator as well, the piezoelectric element 11 can be easily bonded to an appropriate position on the diaphragm 12.

FIG. 7 is a diagram showing another example of the locator for positioning the piezoelectric element 11 in the embodiment.

As shown in FIG. 7, the diaphragm 12D may include locators L8 and L9 as indexes for positioning the piezoelectric element 11 on the first surface 12a. Providing an index such as a line drawn on the first surface 12a like the locators L8 and L9 facilitates proper positioning when the piezoelectric element 11 is bonded to the first surface 12a of the diaphragm 12D. And it can be done reliably. The locators L8 and L9 may be painted on the first surface 12a using, for example, paint. Further, the locators L8 and L9 may be marked on the first surface 12a by using, for example, a scribe. As a simplified example of the diaphragm 12D shown in FIG. 7, for example, only one of the locators L8 and L9 may be provided.

In this way, the diaphragm 12 may use the indicators L and L9 for positioning the joint surface 11a of the piezoelectric element 11 as locators. With such a locator as well, the piezoelectric element 11 can be easily bonded to an appropriate position on the diaphragm 12.

FIG. 8 is an example of functional blocks of the tactile sensation providing apparatus 1 according to the present embodiment. As shown in FIG. 8, the tactile sensation providing apparatus 1 further includes a controller 40. The controller 40 can be configured by a processor capable of executing application software, a microcomputer, or the like. The controller 40 may appropriately include a storage unit configured by a memory or the like that can store various kinds of information as needed.

As shown in FIG. 8, the controller 40 is connected to the actuator 10. The controller 40 outputs a drive signal to the actuator 10. The drive signal is a voltage signal applied to the piezoelectric element 11 of the actuator 10.

The piezoelectric element 11 expands and contracts in the longitudinal direction according to the drive signal acquired from the controller 40. The vibration plate 12 of the actuator 10 illustrated in FIGS. 1 and 2 bends in accordance with the deformation or displacement of the piezoelectric element 11. That is, when the piezoelectric element 11 is deformed or displaced in the contracting direction of the vibration plate 12 in the longitudinal direction, the vibration plate 12 is bent so that the second surface 12b side is convex. When the piezoelectric element 11 is deformed or displaced in the direction in which the vibration plate 12 extends in the longitudinal direction, the vibration plate 12 bends so that the first surface 12a side is convex. In this way, the deformation or displacement of the piezoelectric element 11 is converted into the vibration of the first surface 12a of the vibration plate 12 in the normal direction (Z-axis direction).

In the present embodiment, the piezoelectric element 11 is displaced only in the contracting direction in response to the application of the voltage signal. In this case, the diaphragm 12 vibrates between a state in which the second surface 12b is bent so as to be convex and a normal straight state. The displacement of the piezoelectric element 11 is not limited to the direction of contracting in response to the application of the voltage signal. The piezoelectric element 11 may be configured to be displaced in the extending direction in response to the application of the voltage signal, or may be configured to be displaced in both the extending direction and the contracting direction.

As described above, the controller 40 drives the actuator 10 and vibrates the diaphragm 12. The vibration of the diaphragm 12 is transmitted to the vibration target 30 via the vibration transmission unit 15. Then, the tactile sensation is presented to the user who touches the vibration target 30.

The controller 40 may be connected to the touch sensor 50 as shown in FIG. 8, for example. In this case, the controller 40 may output a drive signal to the actuator 10 according to the signal acquired from the touch sensor 50. The touch sensor 50 may be the vibration target 30 of the tactile sensation providing apparatus 1. In this case, the touch sensor 50 detects that the user is touching the vibration target 30. The controller 40 vibrates the vibration target 30 when the user is touching the vibration target 30. By doing so, the tactile sensation providing apparatus 1 can present the tactile sensation to the user who touches the vibration target 30. The touch sensor 50 may be provided as a configuration separate from the vibration target 30 of the tactile sensation providing apparatus 1.

In the above-described embodiment, the diaphragm 12 and the support portion 13 are described as separate members. In the embodiment, the case where the diaphragm 12 and the support portion 13 are integrally configured will be described. FIG. 9 is a main-portion cross-sectional view showing a configuration example of the tactile sensation providing apparatus 2 according to the embodiment. Hereinafter, differences from the tactile sensation providing apparatus 1 according to the embodiment shown in FIG. 1 and the like will be described.

In this embodiment, the diaphragm 12 and the support 13 are integrally molded. For example, the vibrating plate 12 and the supporting portion 13 can be integrally molded by molding a resin to be the supporting portion 13 around the metallic vibrating plate 12. Alternatively, the vibration plate 12 and the support part 13 can be integrally molded by providing a fitting part on the metal vibration plate 12 and fitting the support part 13 made of resin. Alternatively, the vibration plate 12 and the support portion 13 can be integrally molded by providing a bonding surface coated with a primer on the surface of the metal vibration plate 12 and molding the resin on the bonding surface. Alternatively, the vibration plate 12 and the supporting portion 13 may be integrally molded by providing a finely-bonded bonding surface on the surface of the metal diaphragm 12 and molding a resin on the bonding surface.

As shown in FIG. 9, in the actuator 10 according to the present embodiment, a fixing portion 14 that fixes the actuator 10 to the housing 20 may be provided at the end of the support portion 13. The fixing portion 14 is fixed to the housing 20 by, for example, screwing or bonding. The fixed portion 14 is a thin plate having elasticity, like the diaphragm 12, for example. The fixed portion 14 may be made of the same material as the diaphragm 12, or may be made of a different material.

In the actuator 10 according to this embodiment, the vibration plate 12, the support portion 13, and the fixed portion 14 may be integrally molded. The member in which the diaphragm 12, the support portion 13, and the fixed portion 14 are integrally molded may be the frame of the actuator 10. The frames according to this embodiment may be made of the same material. The frame according to the present embodiment may be integrally molded, for example, by bending a single thin metal plate by sheet metal working. In the frame according to the present embodiment, the diaphragm 12, the support portion 13, and the fixed portion 14 may be welded to each other and integrally molded. The frame according to the present embodiment may be made by integral molding of resin.

According to the actuator 10 according to the embodiment, the diaphragm 12 and the support portion 13 that are different in material are integrally molded.
Compared with the case where the vibration plate 12 and the support part 13 are configured as separate parts, the damping of the vibration of the vibration plate 12 caused by the expansion and contraction displacement of the piezoelectric element 11 is reduced by the support part 13, The number of points and assembly man-hours are reduced. Further, by not using an adhesive agent between the diaphragm 12 and the support portion 13, the mean time interval between failures (MTBF: Mean Time Between Failure) is extended and the yield at the time of assembly is improved.

In the above-described embodiment, the actuator 10 may not have the fixing portion 14. In this case, the end portion of the support portion 13 is joined to the housing 20 by adhesion or the like. The end portion of the support portion 13 may be configured to be swingable around the joined portion.

Although the embodiments according to the present disclosure have been described based on the drawings and the examples, it should be noted that those skilled in the art can easily make various variations and modifications based on the present disclosure. Therefore, it should be noted that these variations and/or modifications are included in the scope of the present disclosure.

DESCRIPTION OF SYMBOLS 1 Tactile sensation providing device 10 Actuator 11 Piezoelectric element 12 Vibrating plate 13 Supporting part 14 Fixing part 15 Vibration transmitting part 20 Housing 30 Vibrating object 40 Controller 50 Touch sensor

Claims (11)

1. A piezoelectric element having a bonding surface,
   A vibration plate to which the bonding surface of the piezoelectric element is bonded and which vibrates according to deformation or displacement of the piezoelectric element,
   Equipped with
   An actuator in which the center of the bonding surface of the piezoelectric element is bonded so that the center of the bonding surface is within a region in the vibration plate where the vibration transmitting unit is arranged.
2. The piezoelectric element has a rectangular parallelepiped shape,
   The actuator according to claim 1, wherein the size of the piezoelectric element in the longitudinal direction and the lateral direction is larger than the size of the piezoelectric element in the thickness direction.
3. The actuator according to claim 2, wherein the center of the joint surface of the piezoelectric element is a point that divides the length of the piezoelectric element in the longitudinal direction into two equal parts.
4. The actuator according to any one of claims 1 to 3, wherein the center of the joint surface of the piezoelectric element is joined so as to be located at the center of a region of the diaphragm where the vibration transmitting unit is arranged.
5. The actuator according to claim 4, wherein a center of a region of the diaphragm where the vibration transmitter is arranged is a center of gravity of a region of the diaphragm where the vibration transmitter is arranged.
6. The diaphragm has a first surface and a second surface opposite to the first surface,
   The piezoelectric element is bonded on the first surface,
   The actuator according to claim 1, wherein the vibration transmission unit is arranged on the second surface.
7. The actuator according to any one of claims 1 to 6, wherein the diaphragm includes a locator that positions the bonding surface of the piezoelectric element.
8. The actuator according to claim 7, wherein the diaphragm includes, as the locator, a recess for positioning the bonding surface of the piezoelectric element.
9. The actuator according to claim 7, wherein the vibrating plate includes, as the locator, a convex portion for positioning the bonding surface of the piezoelectric element.
10. The actuator according to claim 7, wherein the diaphragm includes, as the locator, an index for positioning the bonding surface of the piezoelectric element.
11. An actuator according to any one of claims 1 to 10,
    The vibration of the vibration plate is transmitted, and the vibration target presents a tactile sensation to the user,
    A vibration transmission unit that transmits the vibration of the diaphragm to the vibration target;
    A tactile sensation providing device.
    

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