阅读说明：本技术 振动装置和光学检测装置 (Vibration device and optical detection device ) 是由 石井友基 坂口仁志 藤本克己 于 2019-04-12 设计创作，主要内容包括：提供一种能够抑制振动的泄漏和阻尼的振动装置。本发明的振动装置(1)具备：振动元件(2),其具有包括第1开口端面(3a)和第2开口端面(3b)的筒状的振动体(3)；支承体(15),在将连结振动体(3)的第1开口端面(3a)与第2开口端面(3b)的方向作为轴向时,该支承体沿轴向延伸,且支承振动体(3)；以及连接构件(14),其连接振动体(3)与支承体(15)。振动体(3)以在振动元件(2)的轴向上的不同位置产生第1节点和第2节点的方式进行呼吸振动,连接构件(14)位于第1节点与第2节点之间。(Provided is a vibration device capable of suppressing leakage and damping of vibration. A vibration device (1) is provided with: a vibration element (2) having a tubular vibration body (3) having a 1 st opening end face (3a) and a 2 nd opening end face (3 b); a support body (15) that extends in the axial direction and supports the vibrating body (3) when the direction connecting the 1 st opening end face (3a) and the 2 nd opening end face (3b) of the vibrating body (3) is taken as the axial direction; and a connecting member (14) that connects the vibrating body (3) and the support body (15). The vibrating body (3) is respiratory-vibrated in such a manner as to generate a 1 st node and a 2 nd node at different positions in the axial direction of the vibrating element (2), and the connecting member (14) is located between the 1 st node and the 2 nd node.)

1. A vibration device, wherein,

the vibration device is provided with:

a vibration element having a cylindrical vibrator including a 1 st opening end face and a 2 nd opening end face;

a support member that extends in an axial direction when a direction connecting the 1 st opening end surface and the 2 nd opening end surface of the vibrating body is defined as the axial direction, and supports the vibrating body; and

a connecting member connecting the vibrating body and the support body,

the oscillating body performs respiratory oscillation in such a manner as to generate a 1 st node and a 2 nd node at different positions in the axial direction of the oscillating element,

the connecting member is located between the 1 st node and the 2 nd node.

2. The vibration device according to claim 1,

the 1 st node is located at the vibration body,

in the vibrating body, a displacement amount of the vibration in the axial direction of the portion to which the connecting member is connected is 40% or less of a displacement amount of the vibration in the axial direction of the portion at which the 1 st node is located.

3. The vibration device according to claim 1 or 2,

the vibration element includes a piezoelectric vibrator configured to vibrate the vibrator.

4. The vibration device according to any one of claims 1 to 3,

the support body has a bottom portion and a connecting portion connected to the connecting member;

in the support body, a portion located closer to the connecting portion side than the bottom portion is more easily deformed than the bottom portion.

5. The vibration device according to claim 4,

when the thickness in the direction orthogonal to the axial direction is defined as a thickness, the thickness of the bottom portion of the support body is larger than the thickness of the other portions, and a cross section of the support body in the axial direction has a substantially L-shape.

6. The vibration device according to any one of claims 1 to 5,

the vibrating body, the connecting member, and the support body are made of the same material.

7. The vibration device according to claim 6,

the vibrating body, the connecting member, and the support body are made of a metal material.

8. The vibration device according to any one of claims 1 to 7,

the vibration element has a cover provided on the 1 st opening end face of the vibrator.

9. The vibration device according to claim 8,

the cover body has light transmission.

10. An optical inspection apparatus, wherein,

the optical detection device includes:

the vibration device of claim 9; and

and an optical detection element configured to include a detection region in a cover provided in the vibration device.

11. The optical detection device of claim 10,

the optical detection element is an image pickup element, and the detection area is a visual field.

Technical Field

The present invention relates to a vibration device and an optical detection device.

Background

Conventionally, vibration devices have been widely used in various applications such as removal of raindrops and the like adhering to an optical detection device as a monitoring device, and acoustic devices. When the vibration device is used, the vibration device is fixed to, for example, an external device. In order to suppress leakage and damping of vibration, the vibration device is often fixed to the outside at a portion serving as a node.

Patent document 1 listed below shows an example of a supporting structure of a piezoelectric vibrator. In this support structure, a cylindrical support body is disposed on a side surface of a cylindrical piezoelectric vibrator that performs respiratory vibration. The length of the support body is λ (2n +1)/4 so that the tip of the support body becomes a node, and the tip of the support body is fixed to the outside.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 62-254667

Disclosure of Invention

Problems to be solved by the invention

Since the node does not shift during vibration, leakage and damping of vibration are suppressed when the vibration device is supported at the node. However, it is very difficult to actually support the vibration device at an accurate position to become a node. Therefore, the position at which the vibration device is supported is actually near the position at which the node is formed. At the time of vibration, the displacement becomes larger as the distance from the node becomes larger. Therefore, when the position supporting the vibration device is displaced from the position that becomes the node, it becomes difficult to suppress leakage of vibration from the portion supporting the vibration device and damping of vibration.

Here, during the respiratory vibration, a rotational moment about the node is applied to a portion near the node. Therefore, even if the distal end of the support body serving as the node is connected to the outside as in patent document 1, a rotational moment about the node is applied to the outside, and therefore it is difficult to sufficiently suppress leakage and damping of vibration.

The present invention aims to provide a vibration device and an optical detection device capable of suppressing leakage and damping of vibration.

Means for solving the problems

The vibration device of the present invention includes: a vibration element having a cylindrical vibrator including a 1 st opening end face and a 2 nd opening end face; a support member that extends in an axial direction when a direction connecting the 1 st opening end surface and the 2 nd opening end surface of the vibration body is defined as the axial direction, and supports the vibration body; and a connecting member that connects the oscillating body and the support body, the oscillating body being respiratory-oscillated so as to generate a 1 st node and a 2 nd node at different positions in the axial direction of the oscillating element, the connecting member being located between the 1 st node and the 2 nd node.

The optical detection device of the present invention includes the vibration device configured according to the present invention, and the optical detection element disposed so as to include the detection region in the cover of the vibration device.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a vibration device and an optical detection device capable of suppressing leakage and damping of vibration can be provided.

Drawings

Fig. 1 is a schematic front cross-sectional view of a vibration device according to embodiment 1 of the present invention.

Fig. 2 is a schematic exploded perspective view of the vibration device according to embodiment 1 of the present invention.

Fig. 3 is a schematic front sectional view of an image forming apparatus having a vibration device of embodiment 1 of the present invention.

Fig. 4 is a diagram for explaining the vibration of the vibration device and the position of the connecting member according to embodiment 1 of the present invention.

Fig. 5 is an element vector diagram for explaining the vibration of the vibration device according to embodiment 1 of the present invention.

Fig. 6 is a diagram showing displacement amounts of vibration in the radial direction and the axial direction at each position of the vibrator according to embodiment 1 of the present invention.

Fig. 7 is a diagram showing a relationship between a position of the connecting member in the support body and a displacement amount of the bottom portion of the support body.

Fig. 8 is an element vector diagram of the vibration element in the case where the distance between the nodes is L +1 mm.

FIG. 9 is a vector diagram of elements of the vibration element in the case where the distance between the nodes is L-0.5 mm.

Fig. 10 is an element vector diagram of the vibration element in the case where the distance between the nodes is L +20 mm.

Fig. 11 is a diagram showing the displacement amount of vibration in the axial direction at each position of the vibrator when the distance between the nodes is L +1 mm.

FIG. 12 is a diagram showing the displacement amount of vibration in the axial direction at each position of a vibrating element, where L-0.5mm is the distance between nodes.

Fig. 13 is a diagram showing the displacement amount of vibration in the axial direction at each position of the vibrator when the distance between the nodes is L +20 mm.

Fig. 14 is a diagram for explaining the vibration of the vibration device according to variation 1 of embodiment 1 of the present invention.

Fig. 15 is a schematic front cross-sectional view of a vibration device according to variation 2 of embodiment 1 of the present invention.

Fig. 16 is a schematic plan view of a vibration device according to modification 3 of embodiment 1 of the present invention.

Fig. 17 is a schematic front cross-sectional view of a vibration device according to embodiment 2 of the present invention.

Fig. 18 is a schematic front cross-sectional view of a vibration device according to a modification of embodiment 2 of the present invention.

Fig. 19 is a schematic perspective view of the support body according to embodiment 3 of the present invention.

Fig. 20 is a schematic perspective view of the support body according to embodiment 4 of the present invention.

Fig. 21 is a schematic perspective view of a support body according to modification 1 of embodiment 4 of the present invention.

Fig. 22 is a schematic perspective view of a support body according to modification 2 of embodiment 4 of the present invention.

Fig. 23 is a schematic front sectional view showing a part of a support according to embodiment 5 of the present invention.

Fig. 24 is a schematic front sectional view showing a part of a support according to embodiment 6 of the present invention.

Detailed Description

The present invention will be made clear by the following description of specific embodiments of the present invention with reference to the accompanying drawings.

Note that the embodiments described in the present specification are exemplary, and partial replacement or combination of the structures may be performed between different embodiments.

Fig. 1 is a schematic front cross-sectional view of a vibration device according to embodiment 1 of the present invention. Fig. 2 is a schematic exploded perspective view of the vibration device of embodiment 1.

The vibration device 1 shown in fig. 1 and 2 is a vibration device that removes water droplets and foreign matter from the field of view of the image pickup device by moving the water droplets and foreign matter by vibration. However, the vibration device of the present invention can be used for applications other than the above, such as applications of generating sound pressure, for example, an ultrasonic sensor, a microphone, and a buzzer.

The vibration device 1 has a vibration element 2, a support body 15 supporting the vibration element 2, and a connecting member 14 connecting the vibration element 2 and the support body 15. More specifically, the vibration element 2 has a substantially cylindrical vibration body 3. The vibrating body 3 of the vibrating element 2 and the support body 15 are connected by a connecting member 14. In the vibration device 1, an internal space surrounded by the vibration element 2, the connection member 14, and the support body 15 is configured.

Fig. 3 is a front sectional view of an image forming apparatus having the vibration device of embodiment 1.

An imaging element 10A indicated by a one-dot chain line is disposed in an internal space surrounded by the vibration element 2, the connecting member 14, and the support body 15. The imaging device 10 as an optical detection apparatus of an embodiment of the present invention is thus constituted. The imaging apparatus 10 has a vibration device 1 and an image pickup element 10A. Examples of the imaging element 10A include a CMOS, a CCD, a bolometer, a thermopile, and the like that receive light having any wavelength from the visible region to the far-infrared region. Examples of the imaging device 10 include a camera, a Radar, and a LIDAR device.

In addition, an optical detection element that optically detects energy rays other than the imaging element 10A may be disposed in the internal space. The energy line to be detected may be, for example, an active energy line such as an electromagnetic wave or an infrared ray. The detection region of the optical detection element is included in a light-transmitting body 7 described later. In the imaging apparatus 10 shown in fig. 3, the field of view of the image pickup element 10A is included in the light transmitting body 7. The term "light transmittance" as used herein means a transmittance through which at least energy rays or light of a wavelength detected by the above-mentioned optical detection element passes.

The details of the vibration device 1 will be described below.

As shown in fig. 1, the vibration element 2 includes the vibration body 3, a light-transmitting body 7 as a cover, and a piezoelectric vibrator 8. The vibrator 3 has a 1 st opening end face 3a and a 2 nd opening end face 3b, and an outer side face 3c and an inner side face 3d connecting the 1 st opening end face 3a and the 2 nd opening end face 3 b. In the present specification, the direction connecting the 1 st opening end surface 3a and the 2 nd opening end surface 3b of the vibrator 3 is defined as an axial direction, and the direction orthogonal to the axial direction is defined as a radial direction.

The vibrator 3 includes a cylindrical 1 st vibrator portion 4, a cylindrical 2 nd vibrator portion 5, and an annular connecting portion 6 connecting the 1 st vibrator portion 4 and the 2 nd vibrator portion 5. The vibrating body 3 is a tubular body in which the 1 st vibrating body portion 4, the connecting portion 6, and the 2 nd vibrating body portion 5 are arranged so that their respective central axes are at the same position. The 1 st vibrating body portion 4 includes a 1 st opening end surface 3a of the vibrating body 3. The 2 nd vibrating body portion 5 includes the 2 nd opening end face 3b of the vibrating body 3. The shapes of the 1 st vibration body 4, the 2 nd vibration body 5, and the connection portion 6 are not limited to the above shapes. The 1 st vibration element 4, the 2 nd vibration element 5, and the connection element 6 may be continuously connected to each other in the shape of a single cylindrical body. The vibrating body 3 is not limited to the configuration having the 1 st vibrating body portion 4, the 2 nd vibrating body portion 5, and the connecting portion 6, and may be a cylindrical body. The vibrator 3 may be, for example, substantially square tube-shaped.

Here, in the present specification, unless otherwise specified, the outer peripheral edge and the inner peripheral edge refer to the outer peripheral edge and the inner peripheral edge in a plan view. In a plan view, the outer peripheral edges of the coupling portion 6, the 1 st vibration element 4, and the 2 nd vibration element 5 overlap. On the other hand, the inner peripheral edge of the coupling portion 6 is located outside the inner peripheral edges of the 1 st vibration body portion 4 and the 2 nd vibration body portion 5. When the thickness in the direction orthogonal to the axial direction is defined as the thickness, the thickness of the coupling portion 6 is smaller than the thickness of the 1 st vibration element 4 and the thickness of the 2 nd vibration element 5. In the vibrator 3, the inner diameter of the connecting portion 6 is larger than the inner diameter of the other portions.

The outer side surfaces 3c of the vibrator 3 are formed by connecting the outer side surfaces of the 1 st vibrator portion 4, the connecting portion 6, and the 2 nd vibrator portion 5. Similarly, the inner surface 3d of the vibrator 3 is formed by connecting the inner surfaces of the 1 st vibrator portion 4, the connecting portion 6, and the 2 nd vibrator portion 5. In the present embodiment, the inner surface 3d has a stepped portion in the portion of the coupling portion 6. On the other hand, the outer surface 3c has no step.

A light-transmitting body 7 is provided on the 1 st opening end face 3a of the vibrator 3 so as to cover the opening. The light-transmitting body 7 is a cover having light-transmitting properties. In the present embodiment, the light-transmitting body 7 has a dome shape, but the light-transmitting body 7 may have a flat plate shape. As a material of the light-transmitting body 7, for example, light-transmitting plastic, glass, or light-transmitting ceramic can be used.

The piezoelectric vibrator 8 is provided on the 2 nd opening end face 3b of the vibrator 3. The portion where the piezoelectric vibrator 8 is provided is not limited to the above portion. The piezoelectric vibrator 8 includes an annular piezoelectric body 8 a. The piezoelectric body 8a is made of, for example, Pb (Zr, Ti) O₃、(K、Na)NbO₃Or other suitable piezoelectric ceramics or LiTaO₃、LiNbO₃And the like, are suitably formed of piezoelectric single crystals.

The piezoelectric vibrator 8 includes a 1 st electrode 9a provided on one main surface of the piezoelectric body 8a and a 2 nd electrode 9b provided on the other main surface. The 1 st electrode 9a and the 2 nd electrode 9b are annular and are provided so as to face each other. The 1 st electrode 9a and the 2 nd electrode 9b are electrically connected to the outside, respectively. Although one annular piezoelectric vibrator 8 is provided in the present embodiment, the present invention is not limited to this, and a plurality of rectangular plate-shaped piezoelectric vibrators may be provided along the outer surface 3 c.

The piezoelectric vibrator 8 is joined to the vibrator 3 on the 1 st electrode 9a side. The piezoelectric vibrator 8 performs respiratory vibration, thereby causing the vibrator 3 to perform respiratory vibration and causing the connection body between the vibrator 3 and the light transmitting body 7 to vibrate. Here, the respiratory vibration refers to a vibration mode that is displaced in the radial direction of the annular piezoelectric vibrator or the tubular vibrator. The vibration element 2 may not necessarily include the piezoelectric vibrator 8, and may include a vibrator that causes the vibrator 3 to vibrate in a respiratory manner.

The annular connecting member 14 is connected to the outer surface 3c of the vibrator 3. More specifically, the connecting member 14 has a lateral side and a medial side. The inner surface of the connecting member 14 is connected to the outer surface 3c of the vibrator 3. In the vibration device 1, the connecting member 14 is provided so as to extend radially outward from the outer surface 3c of the vibrator 3. The vibrator 3 and the connecting member 14 may be provided integrally. Here, the position of the connecting member 14 is more specifically shown with reference to fig. 4 described below.

Fig. 4 is a diagram for explaining the vibration of the vibration device and the position of the connecting member in embodiment 1. Fig. 4 shows a portion corresponding to a radial half of the cross section shown in fig. 1.

The vibrator 3 makes respiratory vibrations in such a manner as to generate the 1 st node N1 and the 2 nd node N2 at different positions in the axial direction of the vibration element 2. More specifically, in the present embodiment, the 1 st node N1 is located at the vibration body 3, and the 2 nd node N2 is located at the light-transmitting body 7. The connecting member 14 is located between the 1 st node N1 and the 2 nd node N2.

In addition, although the vibrating body 3 of the present embodiment performs respiratory vibration so as to generate two nodes, respiratory vibration may be performed so as to generate three or more nodes. In this case, the 1 st node N1 and the 2 nd node N2 are also adjacent nodes.

Returning to fig. 1, the support body 15 is connected to the outer side surface of the connecting member 14. The support body 15 has a connection portion 15a as a portion connected to the connection member 14. The support body 15 is connected to the vibrator 3 via the connecting member 14 to support the vibrator 3.

The support body 15 is a cylindrical body extending in the axial direction. The shape of the support body 15 is not limited to the above shape, and may be, for example, a shape extending in the axial direction such as a square tube. The support body 15 has an outer side surface 15c and an inner side surface 15 d. The connecting portion 15a is located near the upper end of the inner surface 15d of the support body 15 in fig. 1. The support body 15 and the connecting member 14 may be provided integrally.

The support body 15 has a bottom portion 15b including a lower end portion in fig. 1. Vibration device 1 is fixed to the outside at bottom portion 15b of support body 15. Alternatively, a bottom plate is joined to bottom portion 15b, and a closed space may be formed by vibration element 2, connection member 14, support body 15, and the bottom plate.

The present embodiment is characterized in that the vibrator 3 is respiratory-vibrated so that the 1 st node and the 2 nd node are generated at different positions in the axial direction of the vibration element 2, and the connecting member 14 connecting the vibrator 3 and the support body 15 is located between the 1 st node and the 2 nd node. This makes it difficult for vibrations to leak to bottom 15b of support body 15. Therefore, when the vibration device 1 is fixed to the outside, vibration damping of the vibration device 1 is less likely to occur. This detail is explained below.

Fig. 5 is an element vector diagram for explaining the vibration of the vibration device according to embodiment 1. Fig. 5 shows the same parts as fig. 4.

As shown in fig. 5, the vibrations around the 1 st node N1 and the 2 nd node N2 of the vibration element 2 have a rotational moment. Therefore, the vibration of the vibration element 2 has a radial component and an axial component. In the present embodiment, the connecting member 14 is located at a portion where the displacement amount of the vibration in the axial direction is about 0 μm. In the present specification, the displacement amount is expressed as an absolute value unless otherwise specified.

Fig. 6 is a diagram showing the displacement amounts of vibration in the radial direction and the axial direction at each position of the vibrator in embodiment 1. In fig. 6, the horizontal axis indicates the axial position of the vibrator. 0mm on the horizontal axis indicates the position of the 1 st opening end face of the vibrator. The solid line in fig. 6 indicates the amount of displacement in the axial direction, and the broken line indicates the amount of displacement in the radial direction. The alternate long and short dash line a indicates the position where the connecting member is disposed, and the alternate long and short dash line B indicates the position of the 1 st node.

As shown in fig. 6, at the position where the connecting member 14 is arranged, the displacement amount of the vibration in the axial direction is about 0 μm, and the displacement amount of the vibration in the radial direction is about 3.3 μm. On the other hand, at the position of the 1 st node, the displacement amount of the vibration in the radial direction is about 0 μm, but the displacement amount of the vibration in the axial direction is about 0.5 μm.

Here, a vibration device having the structure of embodiment 1 and a vibration device of a comparative example in which a connection member is disposed at the position of the 1 st node were manufactured. Next, the displacement amount of the bottom portion of the support body of the vibration device of embodiment 1 and the comparative example was compared. The compared displacement amounts are obtained by combining the radial component and the axial component.

In the comparative example, the amount of displacement of the bottom of the support was about 2.4. mu.m. In contrast, in embodiment 1, the displacement amount of the bottom portion of the support is about 0.2 μm. As described above, in embodiment 1, it is understood that the vibration of the vibration element can be suppressed from leaking to the bottom of the support body.

When the vibrator is subjected to respiratory vibration, a rotational moment is applied to the vicinity of the node about the node. Therefore, even if the connecting member is connected to the position of the 1 st node of the vibrator as in the comparative example, a rotational moment is applied to the connecting member. Here, in the comparative example, the axial position of the connecting member is the same as the axial position of the node. Therefore, the amount of displacement in the width direction is small but the amount of displacement in the axial direction is large for the vibration that leaks to the connection member due to the application of the rotational moment. When the amount of displacement in the axial direction is large with respect to the vibration leaking to the support body via the connecting member, the amount of displacement of the bottom portion of the support body extending in the axial direction also becomes large. Therefore, it becomes difficult to suppress the vibration leakage to the bottom of the support body. Further, when the vibration device is fixed to the outside at the bottom of the support body, vibration of the bottom is restrained, and therefore, it is also difficult to suppress damping of the vibration.

In contrast, in the 1 st embodiment shown in fig. 4, the connecting member 14 is located between the 1 st node N1 and the 2 nd node N2. Between the 1 st node N1 and the 2 nd node N2, two rotational moments about the two nodes are combined, and therefore the amount of displacement in the axial direction becomes small. Thereby, the amount of displacement in the axial direction of the vibration of the connecting member 14 can be effectively reduced. Even if the radial vibration is transmitted to the support body 15 extending in the axial direction, the bottom portion 15b of the support body 15 is not easily displaced. Therefore, the vibration of the vibration element 2 can be suppressed from leaking to the bottom portion 15b of the support body 15. Further, since the amount of displacement of the bottom portion 15b is extremely small, damping of vibration is less likely to occur when the vibration device is fixed to the outside at the bottom portion 15 b.

In the vibrating body 3, the displacement amount of the vibration in the axial direction of the portion to which the connecting member 14 is connected is preferably 90% or less, more preferably 40% or less, of the displacement amount of the vibration in the axial direction of the portion at which the 1 st node N1 is located. However, the amount of displacement in the axial direction is particularly preferably 0 μm. This can further suppress leakage and damping of vibration. This is illustrated by the following figure 7.

Fig. 7 is a diagram showing a relationship between a position of the connecting member in the support body and a displacement amount of the bottom portion of the support body. In addition, when the relationship shown in fig. 7 is obtained, the vibration element, the connecting member, and the support body of embodiment 1 are used, and the positions of the connecting members are made different from each other. In fig. 7, the horizontal axis indicates the axial position of the vibrating body at which the connecting member is disposed. 0mm on the horizontal axis indicates the position of the 1 st opening end face of the vibrator.

A one-dot chain line a in fig. 7 indicates a position where the connecting member is disposed in embodiment 1. The position indicated by the one-dot chain line C is a position where the displacement amount in the axial direction of the vibrator is 90% of the displacement amount of the vibration in the axial direction of the portion where the 1 st node is located. The position indicated by the one-dot chain line D is a position where the displacement amount in the axial direction of the vibrator is 40% of the displacement amount of the vibration in the axial direction of the portion where the 1 st node is located. The two-dot chain line E indicates the amount of displacement of the bottom of the support body when the connecting member is disposed at the 1 st node. The two-dot chain line F indicates the amount of displacement of the bottom portion of the support body in the case where the connecting member is disposed at the position indicated by the one-dot chain line D.

As shown in fig. 7, it is understood that when the connecting member 14 is disposed at the position indicated by the alternate long and short dash line C, the amount of displacement of the bottom portion 15b of the support body 15 can be further reliably reduced. Thus, the leakage of vibration to the bottom portion 15b can be further reliably suppressed. Further, it is understood that, when the connecting member 14 is disposed at the position indicated by the one-dot chain line D, the displacement amount of the bottom portion 15b is about 50% in the case where the connecting member 14 is located at the 1 st node N1, as indicated by the two-dot chain line E and the two-dot chain line F. Thus, the leakage of vibration to the bottom portion 15b can be effectively suppressed. Of course, as in the present embodiment, when the connecting member 14 is located at a portion where the displacement amount in the axial direction is about 0, the leakage of vibration to the bottom portion 15b can be further suppressed.

As described above, between the 1 st node N1 and the 2 nd node N2, the displacement amount of the vibration in the axial direction decreases. Also, the portion of the vibration where the displacement amount of the vibration is 0 is located between the 1 st node N1 and the 2 nd node N2. They are shown below to be independent of the distance between the 1 st node N1 and the 2 nd node N2. In the present specification, unless otherwise specified, the distance between the nodes refers to the distance between the 1 st node N1 and the 2 nd node N2.

A plurality of vibration elements were produced in which the distance between the nodes was different from that in embodiment 1. More specifically, assuming that the distance between the nodes in embodiment 1 is L, the vibration elements having the distances L +1mm, L-0.5mm, and L +20mm are manufactured. Further, the distances between the nodes are made different by making the lengths of the connection portions of the vibrating bodies different in the axial direction. The displacement amount of the vibration of each vibration element was then measured.

Fig. 8 is an element vector diagram of the vibration element in the case where the distance between the nodes is L +1 mm. FIG. 9 is a vector diagram of elements of the vibration element in the case where the distance between the nodes is L-0.5 mm. Fig. 10 is an element vector diagram of the vibration element in the case where the distance between the nodes is L +20 mm.

As shown in fig. 8 to 10, when the distances between the nodes are different, the 1 st node N1 is also located in the vibrating body 3, and the 2 nd node N2 is also located in the light-transmitting body 7. It is understood that the displacement amount of the vibration of the light-transmitting body 7 is larger than the displacement amount of the vibration between the 1 st opening end surface 3a of the vibrating body 3 and the 1 st node N1, regardless of the distance between the nodes. This is because the displacement amount when the light-transmitting body is excited in the resonance region is represented by the product of the displacement amount of the vibrator and Qm of the light-transmitting body. Here, Qm is the reciprocal of the elastic loss coefficient. More specifically, if the vibration generated in the piezoelectric vibrator is transmitted to the vibrator and the vibrator vibrates at the resonance frequency, the displacement of the vibration generated in the piezoelectric vibrator is amplified by Qm times of the vibrator. The amplitude of vibration generated from a piezoelectric vibrator is set to 1, and Qm of the vibrator is set to Qm₁The amplitude of the natural vibration mode of the vibrating body is 1 Xqm₁. If the vibration generated in the piezoelectric vibrator is transmitted to the light-transmitting body via the vibrator and the light-transmitting body vibrates at the resonance frequency, the displacement of the vibration generated in the piezoelectric vibrator is further amplified by Qm times of the light-transmitting body. Qm of the light-transmitting body is set to Qm₂The amplitude of the natural vibration mode of the light-transmitting body is 1 Xqm₁×Qm₂. Therefore, the displacement of the vibration of the vibrating body at the time of resonance is smaller than the displacement of the vibration of the light transmitting body. In addition, the above relationship is related to the light-transmitting bodyThe cover of (2) is established regardless of the material of the cover having no light-transmitting property.

Fig. 11 is a diagram showing the displacement amount of vibration in the axial direction at each position of the vibrator when the distance between the nodes is L +1 mm. FIG. 12 is a diagram showing the displacement amount of vibration in the axial direction at each position of a vibrating element when the distance between nodes is L-0.5 mm. Fig. 13 is a diagram showing the displacement amount of vibration in the axial direction at each position of the vibrator when the distance between the nodes is L +20 mm. In fig. 11 to 13, 0mm on the horizontal axis indicates the position of the 1 st opening end face of the vibrator.

As shown in fig. 11, when the distance between the nodes is L +1mm, the portion where the displacement amount of the vibration in the axial direction is 0 is located between the 1 st node N1 and the 2 nd node N2, as in embodiment 1. Further, the closer the position of the vibrator 3 shown on the horizontal axis is to the position of the portion where the displacement amount of the vibration in the axial direction is 0, the closer the displacement amount of the vibration in the axial direction is to 0. Therefore, it is understood that the displacement amount of the vibration in the axial direction is small between the 1 st opening end surface 3a having a value of 0mm on the abscissa and the 1 st node N1. Similarly, as shown in fig. 12 and 13, when the distance between the nodes is L-0.5mm and L +20mm, the portion where the displacement amount of the vibration in the axial direction is 0 is located between the 1 st node N1 and the 2 nd node N2. Further, it is understood that the amount of displacement in the axial direction between the 1 st node N1 and the 2 nd node N2 is reduced. Thus, regardless of the distance between the nodes, it is found that the portion where the displacement amount of the vibration in the axial direction is 0 is located between the 1 st node N1 and the 2 nd node N2, and the displacement amount in the axial direction is reduced between the 1 st aperture end surface 3a and the 1 st node N1.

As described above, the displacement amount of the light transmitting body 7 in which the 2 nd node N2 is located is larger than the displacement amount of the vibration between the 1 st opening end surface 3a of the vibrator 3 and the 1 st node N1. Therefore, it is understood that the amount of displacement in the axial direction between the 1 st node N1 and the 2 nd node N2 is reduced regardless of the distance between the nodes.

Returning to fig. 1, the material of the support body 15 is preferably a material having elasticity, such as a metal material. In this case, the support 15 is easily deformed. This makes it easy for the vicinity of the connection portion 15a of the support body 15 to deform when the vibration of the vibration element 2 is transmitted to the support body 15 via the connection member 14. Therefore, the entire support body 15 can be suppressed from being displaced integrally, and the bottom portion 15b of the support body 15 can be suppressed from being displaced. Therefore, leakage of vibration to the bottom portion 15b can be effectively suppressed, and damping of vibration can also be effectively suppressed. In addition, since the rigidity can be improved even when the material of the support body 15 is a metal material, the support body is not easily broken in addition to the above-described effects. When the vibrator 3 is made of a metal material, an insulating film is preferably provided between the piezoelectric vibrator 8 and the vibrator 3.

The vibrating body 3, the connecting member 14, and the support body 15 are preferably composed of the same material. In this case, reflection of vibration and the like can be suppressed, and the vibration of the vibration device 1 is less likely to be attenuated. The vibrator 3, the connecting member 14, and the support body 15 are more preferably made of a metal material. Thus, as described above, leakage and damping of vibration can be effectively suppressed. The vibrator 3, the connecting member 14, and the support 15 may be made of a ceramic material or the like.

The following describes modifications 1 to 3 of embodiment 1. In the 1 st to 3 rd modifications as well, the leakage and damping of the vibration can be suppressed as in the 1 st embodiment.

In the 1 st modification shown in fig. 14, both the 1 st node N1 and the 2 nd node N2 are located at the vibrator 3, and the connecting member 14 is located between the 1 st node N1 and the 2 nd node N2.

In a modification 2 shown in fig. 15, a disc-shaped cover 27 having no light-transmitting property is provided on the 1 st opening end face 3a of the vibrator 3. The lid 27 is made of, for example, a metal material, a ceramic material, or the like. The vibration device of the present modification can be used for applications such as an ultrasonic sensor, a microphone, and a buzzer that generate sound pressure.

In a modification 3 shown in fig. 16, the vibrator 3 and the support body 15 are connected by a plurality of connecting members 24 arranged in a distributed manner in a circumferential direction with an axial direction as a rotation axis. In fig. 16, the connecting member 24 is indicated by hatching. Each connecting member 24 has the shape of an arc of a circular ring. As with embodiment 1, the plurality of connecting members 24 are located between node 1N 1 and node 2N 2.

Fig. 17 is a schematic front sectional view of the vibration device of embodiment 2.

The present embodiment is different from embodiment 1 in that the thickness of the bottom portion 35b of the support body 35 is larger than the thickness of the other portions. More specifically, the thickness of the support body 35 is the same in portions other than the bottom portion 35 b. The bottom portion 35b extends radially outward, and the cross section of the support body 35 in the axial direction has a substantially L-shape. The vibration device of the present embodiment has the same configuration as the vibration device 1 of embodiment 1 except for the above-described different points.

In the support 35, the thickness of the portion other than the bottom portion 35b is smaller than that of the bottom portion 35b, and therefore the portion located closer to the connection portion 15a than the bottom portion 35b is more easily deformed than the bottom portion 35 b. Thus, when the vibration of the vibration element 2 is transmitted to the support body 35 via the connecting member 14, the portion on the connecting portion 15a side can be more easily deformed than the bottom portion 35 b. Therefore, the support body 35 can be further suppressed from being integrally displaced as a whole. Moreover, since the bottom portion 35b is thick, displacement of the bottom portion 35b can be further suppressed. Therefore, the leakage of the vibration to the bottom portion 35b can be further suppressed, and the damping of the vibration can also be further suppressed.

The extending direction of the bottom portion 35b of the support 35 is not limited to the radially outer side. In the modification example of embodiment 2 shown in fig. 18, the bottom portion 45b of the support 45 extends radially inward, and the support 45 has a substantially L-shaped cross section in the axial direction. In this case, too, the leakage and damping of the vibration can be further suppressed. And the vibration device can be miniaturized.

Fig. 19 is a schematic perspective view of the support body according to embodiment 3.

The present embodiment differs from embodiment 1 in that the support body 55 has a substantially square tubular shape, and the outer side surface 55c is inclined with respect to the axial direction. The vibration device of the present embodiment has the same configuration as the vibration device 1 of embodiment 1 except for the above-described different points.

The outer peripheral edge of the support 55 is square in shape in plan view. The outer surface 55c of the support 55 has a shape in which four trapezoidal surfaces are connected. On the other hand, the inner surface 55d has a cylindrical shape as in embodiment 1.

The outer surface 55c of the support 55 is inclined with respect to the axial direction so that the thickness thereof becomes thinner from the bottom portion 55b side toward the connection portion 15a side. Thus, the portion located closer to the connecting portion 15a than the bottom portion 55b is more easily deformed than the bottom portion 55 b. Thus, as in embodiment 2, the leakage of vibration to the bottom portion 55b of the support body 55 can be effectively suppressed, and the damping of vibration can also be effectively suppressed. The shape of the outer peripheral edge of the support body 55 in plan view may be, for example, a polygon other than a square, a substantially polygon, or a circle or a substantially circle.

Although the outer surface 55c of the support body 55 is inclined with respect to the axial direction in the present embodiment, the outer surface 55c may be stepped so that the thickness thereof becomes thinner as it goes from the bottom portion 55b side toward the connection portion 15a side. In this case, too, leakage and damping of vibration can be suppressed.

Fig. 20 is a schematic perspective view of the support body according to embodiment 4.

The shape of the support 65 of the present embodiment is different from that of embodiment 1. The vibration device of the present embodiment has the same configuration as the vibration device 1 of embodiment 1 except for the above-described different points.

More specifically, the support body 65 has a frame-shaped bottom portion 65b having a square inner peripheral edge and a square outer peripheral edge. One end of the column portion 65e is connected to each corner of the bottom portion 65 b. The column portion 65e extends in the axial direction. In the present embodiment, the thickness of the column portion 65e of the support body 65 is constant and is the same as the thickness of the bottom portion 65 b. The other end of each pillar portion 65e is connected to the frame-shaped portion 65 f. More specifically, the frame-like portion 65f has a square outer peripheral edge and a circular inner peripheral edge. Each column portion 65e is connected to each corner of the frame-shaped portion 65 f. The inner peripheral edge of the frame-like portion 65f is a connecting portion 15a connected to the connecting member 14.

In the support body 65, the column portion 65e is more easily deformed in the direction orthogonal to the axial direction than the frame-shaped bottom portion 65 b. Thus, as in embodiment 2, the leakage of vibration to the bottom portion 65b of the support body 65 can be effectively suppressed, and the damping of vibration can also be effectively suppressed. The outer peripheral edges of the bottom portion 65b and the frame-like portion 65f may have a polygonal shape other than a square shape or a substantially polygonal shape, or may have a circular shape or a substantially circular shape, for example.

Here, the thickness of the column portion 65e of the support body 65 may be different from the thickness of the bottom portion 65 b. In a support body 75 according to variation 1 of embodiment 4 shown in fig. 21, a thickness of a bottom portion 75b is larger than a thickness of a column portion 65 e. Thereby, the bottom portion 75b can be further suppressed from being displaced. Therefore, the leakage of the vibration to the bottom portion 75b can be further suppressed, and the damping of the vibration can also be further suppressed. In the present modification, the bottom portion 75b extends outward in the direction orthogonal to the axial direction, but the bottom portion 75b may extend inward in the direction orthogonal to the axial direction.

In the support body 65 shown in fig. 20, the thickness of the column portion 65e is constant, but is not limited thereto. In a modification 2 of embodiment 4 shown in fig. 22, a section of the column portion 76e of the support body 76 along the axial direction has a substantially right-angled triangular shape. The thickness of the pillar portion 76e becomes thinner from the bottom portion 76b side toward the connecting portion 15a side. Thus, the portion located closer to the connecting portion 15a than the bottom portion 76b is more easily deformed than the bottom portion 76 b. Thus, as in embodiment 3, the leakage of vibration to the bottom portion 76b of the support body 76 can be effectively suppressed, and the damping of vibration can also be effectively suppressed.

Fig. 23 is a schematic front sectional view showing a part of the support body according to embodiment 5.

The present embodiment differs from embodiment 1 in that the outer surface 85c and the inner surface 85d of the support 85 have a wavy shape. The vibration device of the present embodiment has the same configuration as the vibration device 1 of embodiment 1 except for the above-described different points.

The outer surface 85c and the inner surface 85d of the support 85 are curved and have a wavy shape. More specifically, the outer side surface 85c is formed in a wave shape such that the repeated outer diameter increases from the bottom portion side toward the connection portion side and then decreases from the bottom portion side toward the connection portion side. The inner surface 85d is formed in a wave shape such that the repeated inner diameter increases from the bottom portion side toward the connection portion side and then decreases from the bottom portion side toward the connection portion side. The support 85 is a shape that repeatedly changes in thickness so as to become thicker from the bottom portion side toward the connection portion side, and then changes in thickness so as to become thinner from the bottom portion side toward the connection portion side.

Since the outer surface 85c and the inner surface 85d of the support 85 have a wavy shape, the elasticity of the portion on the side of the connection portion can be improved as compared with the bottom portion of the support 85. This can suppress the entire support 85 from being displaced integrally, and can suppress the bottom of the support 85 from being displaced. Therefore, the leakage of the vibration to the bottom can be effectively suppressed, and the damping of the vibration can also be effectively suppressed.

Here, the outer surface 85c of the support 85 is defined as a mountain portion where the outer diameter of the support 85 starts to decrease as it increases from the bottom portion side toward the connection portion side. The point where the outer diameter starts to increase as it decreases from the bottom portion side toward the connection portion side is defined as a valley portion. On the other hand, the inner surface 85d of the support 85 is a mountain portion where the inner diameter of the support 85 starts to increase as it decreases from the bottom portion side toward the connection portion side. The point at which the inner diameter starts to decrease as it increases from the bottom portion side toward the connection portion side is defined as a valley portion. The mountain portion of the outer side surface 85c and the mountain portion of the inner side surface 85d are preferably the same in the axial direction. Likewise, the portions of the valleys of the outer side surface 85c and the portions of the valleys of the inner side surface 85d are preferably axially identical. This can suitably increase the elasticity of the support 85.

The cross-sectional shape of the support 85 in the axial direction is more preferably axisymmetric with respect to an axis of symmetry extending in the axial direction. Thereby, the elasticity can be effectively improved.

The outer surface 85c and the inner surface 85d of the support 85 may have a linear and wavy shape. In this case, too, the elasticity can be improved, and leakage and damping of vibration can be suppressed.

Fig. 24 is a schematic front sectional view showing a part of the support body according to embodiment 6.

The present embodiment is different from embodiment 2 in that both the outer surface 95c and the inner surface 95d of the support 95 have a stepped shape. The vibration device of the present embodiment has the same configuration as that of the vibration device of embodiment 2 except for the above-described different points.

The support body 95 is curved in a step shape at a plurality of portions. More specifically, in the support body 95, the axially extending portions are alternately connected with the radially extending portions. This can increase the elasticity of the support 95. Therefore, as in embodiment 5, leakage and damping of vibration can be suppressed.

In the support body 95, the thickness of the bottom portion 95b is larger than the thickness of the portion extending in the axial direction. Therefore, as in embodiment 2, displacement of the bottom portion 95b can be further suppressed. Therefore, leakage of vibration to the bottom portion 95b can be further suppressed, and also damping of vibration can be further suppressed.

Description of the reference numerals

1. A vibrating device; 2. a vibrating element; 3. a vibrating body; 3a, 1 st opening end surface; 3b, the 2 nd opening end surface; 3c, an outer side surface; 3d, inner side surface; 4. 1 st vibration body; 5. a 2 nd vibrating body; 6. a connecting portion; 7. a light transmitting body; 8. a piezoelectric vibrator; 8a, a piezoelectric body; 9a, 1 st electrode; 9b, the 2 nd electrode; 10. an imaging device; 10A, an imaging element; 14. a connecting member; 15. a support; 15a, a connecting part; 15b, a bottom; 15c, an outer side surface; 15d, inner lateral surface; 24. a connecting member; 27. a cover body; 35. a support; 35b, bottom; 45. a support; 45b, bottom; 55. a support; 55b, bottom; 55c, an outer side surface; 55d, inner side; 65. a support; 65b, bottom; 65e, a column portion; 65f, a frame-shaped portion; 75. a support; 75b, bottom; 76. a support; 76b, bottom; 76e, a column portion; 85. a support; 85c, an outer side surface; 85d, the inner side; 95. a support; 95b, bottom; 95c, an outer side surface; 95d, medial surface.