JP2010089042A - Mounting structure of magnetostriction actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting structure of magnetostriction actuator capable of making a magnetostriction actuator thin in thickness and also keeping its performance compatively. <P>SOLUTION: The magnetostriction actuator which transmits vibrations due to a magnetostriction phenomenon is mounted by: a wall of which one side surface is connected to a vibration transmission part of the magnetostriction actuator; and an elastomer which has the peripheral part connected with the same surface as the surface connected with the magnetostriction actuator, of the wall and the center part connected with the upper surface of the magnetostriction actuator, and pressurizes the magnetostriction actuator together with the wall. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnetostrictive actuator mounting structure, and more particularly to a magnetostrictive actuator mounting structure mounted on an electronic device such as a rice cooker, a washing machine, or a laptop computer.

  Conventionally, there has been technology to drive the wall surface using a magnetostrictive actuator and generate sound from the wall surface itself, but with the recent downsizing and thinning of equipment, the magnetostrictive actuator built into the equipment has also become thin. The demand is growing.

  A conventional magnetostrictive actuator mounting structure will be described with reference to the drawings.

  FIG. 13 is a cross-sectional view showing a conventional magnetostrictive actuator mounting structure.

  In FIG. 13, a magnetostrictive element 101, a coil bobbin 102, a coil 103, a magnet 104, a vibration transmitting portion 105, a yoke 106 forming a magnetic circuit, a spring 107, an exterior case 108, a screw 109, and a nut. A magnetostrictive actuator 100 composed of 110 is attached to a wall surface 111.

The magnetostrictive element 101 and the coil bobbin 102 are arranged so as to be concentric. A coil 103 is wound around the coil bobbin 102. Magnets 104 are bonded to the upper and lower surfaces of the magnetostrictive element 101, respectively. A vibration transmitting unit 105 is joined to the magnet 104 joined to the lower surface of the magnetostrictive element 101. The vibration transmitting unit 105 has a protruding portion that protrudes from the outer peripheral portion at the center. One end of a spring 107 is coupled to the outer periphery of the vibration transmitting unit 105. A yoke 106 that bypasses the outer periphery of the coil 103 and is coupled to the other end of the spring 107 guides the magnetic flux to the magnetostrictive element 101. Further, a part of the yoke 106 is opened, and a protruding portion provided at the center of the vibration transmitting portion 105 protrudes from the opening. The tip of the protrusion provided at the center of the vibration transmitting portion 105 is coupled to the wall surface 111. In addition, the outer case 108 is joined to the upper surface of the yoke 106, and the magnetostrictive actuator 100 can be attached to the wall surface 111 with screws 109 and nuts 110 (see, for example, Patent Document 1 below).
JP 2005-303462 A

  However, the conventional magnetostrictive actuator and the mounting structure on the wall surface provide a suitable compressive stress to the magnetostrictive element, expands the magnetostriction amount of the magnetostrictive element and improves the characteristics, and fixes the magnetostrictive actuator and is waterproof and dustproof. Since the exterior case to be performed was a separate member, it was an obstacle to the reduction in the number of parts and the miniaturization. In particular, home appliances such as rice cookers and washing machines require smaller devices, and with conventional magnetostrictive actuator mounting structures, the actuator must be miniaturized by shortening the magnetostrictive element. As a result, the performance was degraded.

  An object of the present invention is to provide a mounting structure for a magnetostrictive actuator that can achieve both miniaturization and performance maintenance.

  In the magnetostrictive actuator mounting structure of the present invention, a magnetostrictive actuator for transmitting vibration due to a magnetostriction phenomenon is formed by connecting a magnetostrictive actuator having one wall connected to the vibration transmitting portion of the magnetostrictive actuator and an outer peripheral portion of the wall. The center portion is coupled to the upper surface of the magnetostrictive actuator and is attached to the wall surface by an elastic body that presses the magnetostrictive actuator together with the wall surface.

  According to the present invention, by applying an appropriate compressive stress to the magnetostrictive element and using an elastic body that can be attached to the wall surface, the spring constituting the magnetostrictive actuator is no longer required, and miniaturization and performance maintenance can be achieved. Both realization can be achieved.

(Embodiment 1)
A magnetostrictive actuator mounting structure according to Embodiment 1 of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing a magnetostrictive actuator mounting structure according to Embodiment 1 of the present invention, FIG. 2 is a plan view of the same embodiment, FIG. 3 is a front view of the same embodiment, and FIG. It is structural sectional drawing in AA '.

  1 to 4, the magnetostrictive actuator 200 includes a magnetostrictive element 201, a coil bobbin 202, a coil 203, a magnet 204, a vibration absorbing material 205, a vibration transmission unit 206, and a yoke 207.

  The magnetostrictive element 201 changes its dimensions according to the magnitude of the external magnetic field, and is composed of a ferromagnetic material such as nickel, cobalt, or iron, or an alloy based on these materials. The magnetostrictive actuator is a device that utilizes the dimensional change of the magnetostrictive element as vibration. The magnetostrictive element 201 is particularly preferably a supermagnetic material composed of an alloy of iron (Fe) and a rare earth such as terbium (Tb) or dysprosium (Dy). When such a supermagnetic material is used, the magnetostrictive element 201 is a supermagnetostrictive element, the magnetostrictive actuator 200 is a supermagnetostrictive actuator, and the magnetostrictive element 201 has a magnetostriction amount and a permeability when pressed. Change.

  The coil bobbin 202 is made of a nonmagnetic material such as resin, and includes a cylindrical portion and upper and lower flange portions. The upper flange portion of the coil bobbin 202 is coupled to the yoke 207. The coil bobbin 202 may or may not be coupled to the side surface of the giant magnetostrictive element 201 on the inner periphery of the cylindrical portion. The coil 203 is wound around the outer periphery of the cylindrical portion of the coil bobbin 202.

  The magnet 204 is configured in a ring shape, and applies a bias magnetic field to the magnetostrictive element 201 to increase the operating point in advance, thereby enabling the behavior as a vibrator. The vibration absorbing material 205 is made of a resin that absorbs vibration such as a ring-shaped rubber or a spring. Accordingly, since the vibration absorbing material 205 suppresses unnecessary vibration, the magnetostrictive actuator 200 can perform an operation faithful to the input signal. The vibration transmitting unit 206 is made of an optimal resin or metal that matches the material of the wall surface 209 and can control sound quality. The lower surface of the vibration transmitting unit 206 is coupled to the upper surface of the wall surface 209.

  The yoke 207 is made of a magnetic material such as iron, and includes a substantially disc-shaped lid portion 207a, a substantially disc-shaped first bottom portion 207b, and a substantially ring-shaped second bottom portion 207c. The yoke 207 guides the magnetic flux generated by the bias magnet 204 to the magnetostrictive element 201.

  The lower surface on the center side of the lid portion 207 a is coupled to the upper surface of the magnetostrictive element 201. The lower surface on the outer peripheral side of the lid portion 207 a is coupled to the upper surface of the bias magnet 204.

  The upper surface of the first bottom portion 207 b is coupled to the lower surface of the magnetostrictive element 201. The side surface of the first bottom portion 207 b is coupled to the inner periphery of the vibration absorbing material 205. The first bottom portion 207b is held by the vibration absorbing material 205 at the center position in the lateral direction of the first bottom portion 207b. The lower surface of the first bottom portion 207 b is coupled to the upper surface of the vibration transmission unit 206.

  The upper surface of the second bottom portion 207 c is coupled to the lower surface of the magnet 204. The inner periphery of the second bottom portion 207 c is coupled to the outer periphery of the vibration absorbing material 205. The vibration absorbing material 205 is provided by a flange provided on the upper surface side of the first bottom portion 207b and projecting in the outer diameter direction, and a flange provided on the lower surface side of the second bottom portion 207c and projecting in the center direction. There is a step. These two flanges increase the contact area between the vibration absorbing material 205 and the first bottom portion 207b and the second bottom portion 207c. Therefore, the coupling strength between the vibration absorbing material 205 and the first bottom portion 207b and the second bottom portion 207c can be increased.

  The leaf spring 208 includes a central portion 208a that is raised on the center side, and an outer peripheral portion 208b that is flat on the outer peripheral side. The center portion 208a is recessed in the vicinity of the center and in the vicinity thereof. And the upper surface of the cover part 207a is fixed by the lower surface of this hollow part.

  This point will be described in detail with reference to FIG. FIG. 5 is a state diagram illustrating a state before the wall surface 209 and the leaf spring 208 are coupled to each other and a state of the magnetostrictive actuator 200 after the coupling. As shown in FIG. 5A, the leaf spring 208 before being coupled to the wall surface 209 is not applied with a restoring force. There is a gap between the leaf spring 208 and the wall surface 209. As shown in FIG. 5 (a), the outer peripheral portion 208b of the leaf spring 208 is pulled downward from the state before the wall surface 209 and the leaf spring 208 are joined together, as shown in FIG. 5 (b). The wall surface 209 and the leaf spring 208 are coupled to each other. At this time, the leaf spring 208 is subjected to a restoring force that attempts to return to the original state where no restoring force is applied, as shown in FIG. As a reaction of the restoring force, a downward force is applied to the central portion 208a of the leaf spring 208, and compressive stress is continuously applied to the lid portion 207a of the magnetostrictive actuator 200 fixed to the central portion 208a of the leaf spring 208.

  In addition, the smaller the contact area between the central portion 208a and the lid portion 207a, the smaller the external force for applying an appropriate pressure, so that the failure of the leaf spring 208 exceeding the elastic limit can be suppressed.

  On the other hand, when the central portion 208a and the lid portion 207a are coupled at a single point and the magnetostrictive actuator 200 is fixed, the leaf spring 208 continues to apply an appropriate compressive stress to the magnetostrictive element 201, thereby increasing the amount of magnetostriction due to the magnetostriction phenomenon. can do. The central portion 208a may be coupled to the upper surface of the lid portion 207a on the lower surface to fix the magnetostrictive actuator 200, and may not be fixed at one point. Adhesive is applied to the entire lower surface of the outer peripheral portion 208b and joined to the wall surface 209.

  As described above, the magnetostrictive actuator 200 is pressed by the wall surface 209 and the leaf spring 208, and an appropriate compressive stress is continuously applied to the internal magnetostrictive element 201. As a result, the magnetostrictive actuator 200 can further increase the amount of magnetostriction due to the magnetostriction phenomenon of the magnetostrictive element 201, and a large stroke can be taken. Therefore, there is a spring inside from the wall surface to which the magnetostrictive actuator is attached. Thus, it is possible to generate a sound equivalent to the case where the conventional magnetostrictive actuator is attached, and it is possible to realize a thinner thickness than the conventional one.

  Further, by using a leaf spring that forms a sealed space as shown in FIG. 6, the magnetostrictive actuator 200 is protected from dust, water, temperature, etc. even in a poor environment in the home, and failure is prevented even in long-term use. Can do.

(Embodiment 2)
A magnetostrictive actuator mounting structure according to Embodiment 2 of the present invention will be described below with reference to the drawings. In addition, the same part as Embodiment 1 attaches | subjects the same number, and abbreviate | omits description.

  FIG. 7 is a structural cross-sectional view showing a magnetostrictive actuator mounting structure according to Embodiment 2 of the present invention. The magnetostrictive actuator 300 further includes a cushion 301 that is an elastic body. The cushion 301 has a lower surface coupled to the lid portion 207 a and an upper surface coupled to the center portion 208 a of the leaf spring 208. The leaf spring 208 presses the magnetostrictive actuator 300 toward the wall surface via the cushion 301 by a restoring force. For this reason, by changing the thickness of the cushion 301, it is possible to use a small number of types of leaf springs as they are for actuators having various thicknesses, and the versatility as a component is improved.

(Embodiment 3)
Hereinafter, a magnetostrictive actuator mounting structure according to Embodiment 3 of the present invention will be described with reference to the drawings. In addition, the same part as Embodiment 1 and Embodiment 2 attaches | subjects the same number, and abbreviate | omits description.

  FIG. 8 is a plan view showing a mounting structure of the magnetostrictive actuator 400 according to Embodiment 3 of the present invention. FIG. 9 is a structural cross-sectional view taken along the line BB ′ in FIG. As shown in FIGS. 8 and 9, the wall surface 209 includes a plurality of clamp portions 401.

  Next, a procedure for attaching the leaf spring 208 to the wall surface 209 will be described. First, the leaf spring 208 is disposed on the wall surface 209 where the clamp portion 401 is not provided. Then, the leaf spring 208 is rotated about a straight line drawn perpendicularly to the paper surface of FIG. 8 as a rotation axis, and is inserted into the clamp portion 401 and fixed. And the leaf | plate spring 208 and the clamp part 401 are couple | bonded using an adhesive agent.

  Thereby, since the wall surface 209 and the leaf | plate spring 208 can be joined mechanically, joining strength increases compared with the case where it joins only using an adhesive agent.

(Embodiment 4)
Hereinafter, a magnetostrictive actuator mounting structure according to Embodiment 4 of the present invention will be described with reference to the drawings. The same parts as those in the first to third embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 10 is a structural sectional view showing a mounting structure of the magnetostrictive actuator 500 according to the fourth embodiment of the present invention. A plurality of holes are provided in the outer peripheral portion 208 b of the leaf spring 208 and the outer peripheral side of the wall surface 209 so as to pass the screw 501 and the nut 502. The leaf spring 208 is fixed to the wall surface 209 with screws 501 and nuts 502.

  Thereby, since the wall surface 209 and the leaf | plate spring 208 can be joined mechanically, joining strength increases compared with the case where it joins only using an adhesive agent.

(Embodiment 5)
Hereinafter, a magnetostrictive actuator mounting structure according to Embodiment 5 of the present invention will be described with reference to the drawings. The same parts as those in the first to fourth embodiments are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 11 is a structural sectional view showing a mounting structure of the magnetostrictive actuator 600 according to the fifth embodiment of the present invention. The leaf spring 208 includes a male screw portion 601 at the entire outer edge of the outer peripheral portion 208b. Further, the wall surface 209 is provided with a concave machining in accordance with the size of the male screw portion 601 of the leaf spring 208, and a female screw portion 602 is provided on the entire edge of the inner circumference of the concave machining portion. The male screw portion 601 of the leaf spring 208 is screwed into the female screw portion 602 of the wall surface 209, and the wall surface 209 and the leaf spring 208 are fixed.

  Thereby, since the wall surface 209 and the leaf | plate spring 208 can be joined mechanically, joining strength increases compared with the case where it joins only using an adhesive agent.

(Embodiment 6)
Hereinafter, a moving body using the magnetostrictive actuator mounting structure according to Embodiment 6 of the present invention will be described with reference to the drawings. The same parts as those in the first to fifth embodiments are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 12 is a sectional view of an automobile using the magnetostrictive actuator mounting structure according to Embodiment 6 of the present invention. For example, the magnetostrictive actuator 700 is attached to a door or window that constitutes an automobile 701 that is a moving body.

  This makes it possible to install the magnetostrictive actuator in a narrower space than in the past, and by using a leaf spring that forms a sealed space, heat, dust, water, etc. do not enter from the outside and it is difficult to break down. It is possible to function as an acoustic device while suppressing breakdown even in a use environment.

  In addition, the magnetostrictive actuator may be attached to a surface part constituting a home appliance such as a rice cooker or a refrigerator, or a surface part constituting an electronic device such as a personal computer or a mobile phone, or to a building such as a ceiling material for a house or a wall material. You may attach to the surface part which comprises household equipment, such as furniture, a bathtub, and a toilet.

  The mounting structure of the magnetostrictive actuator of the present invention is useful as a mounting structure of a magnetostrictive actuator used in acoustic applications, which is mounted on home appliances such as rice cookers and washing machines installed in residential spaces, and AV equipment such as a television set. It is.

The perspective view which shows the attachment structure of the magnetostrictive actuator in Embodiment 1 of this invention The top view which shows the attachment structure of the magnetostriction actuator in the embodiment Front view showing mounting structure of magnetostrictive actuator in same embodiment Structural sectional view taken along the line AA 'in FIG. The state diagram which shows the coupling | bonding state of the leaf | plate spring, magnetostrictive actuator, and wall surface in Embodiment 1 of this invention. The perspective view which shows the attachment structure of the other magnetostrictive actuator in Embodiment 1 of this invention. Structural sectional view showing a magnetostrictive actuator mounting structure in Embodiment 2 of the present invention The top view which shows the attachment structure of the magnetostriction actuator in Embodiment 3 of this invention Structural cross-sectional view along BB 'in FIG. Structural sectional view showing a magnetostrictive actuator mounting structure in Embodiment 4 of the present invention Structural sectional drawing which shows the attachment structure of the magnetostrictive actuator in Embodiment 5 of this invention Sectional drawing of the mobile body carrying the magnetostrictive actuator in Embodiment 6 of this invention Structural sectional view showing mounting structure of conventional magnetostrictive actuator

Explanation of symbols

100, 200, 300, 400, 500, 600, 700 Magnetostrictive actuator 101, 201 Magnetostrictive element 102, 202 Coil bobbin 103, 203 Voice coil 104, 204 Bias magnet 105 Vibration transmitting part 106 Yoke 107 Spring 108 Outer case 109, 501 Screw 110 , 502 Nut 111, 209 Wall surface 205 Vibration absorbing material 206 Vibration transmitting portion 207 Yoke 207a Lid portion 207b First bottom portion 207c Second bottom portion 208 Leaf spring 208a Center portion 208b Outer peripheral portion 301 Cushion 401 Clamp portion 601 Male screw portion 602 Female Screw part 701 Car

Claims (11)

A magnetostrictive actuator that transmits vibration due to the magnetostriction phenomenon
A wall whose one surface is coupled to the vibration transmitting portion of the magnetostrictive actuator;
The outer peripheral portion is coupled to the same surface of the wall surface to which the magnetostrictive actuator is coupled, and the central portion is coupled to the upper surface of the magnetostrictive actuator, and the elastic body presses the magnetostrictive actuator together with the wall surface. A magnetostrictive actuator mounting structure characterized by being mounted on a wall surface. The magnetostrictive actuator mounting structure according to claim 1, wherein the elastic body is a leaf spring. The magnetostrictive actuator mounting structure according to claim 1, wherein the magnetostrictive actuator is sealed and pressed by the wall surface and the elastic body and attached to the wall surface. The magnetostrictive actuator mounting structure according to claim 1, wherein the magnetostrictive actuator is a giant magnetostrictive actuator that transmits vibration by a giant magnetostriction phenomenon. The mounting structure for a magnetostrictive actuator according to claim 1, wherein the wall surface is a wall surface that constitutes a home appliance. The magnetostrictive actuator mounting structure according to claim 1, wherein the wall surface is a wall surface constituting an electronic device. The mounting structure for a magnetostrictive actuator according to claim 1, wherein the wall surface is a wall surface constituting a moving body. The mounting structure for a magnetostrictive actuator according to claim 1, wherein the wall surface is a wall surface constituting a building. 5. The magnetostrictive actuator mounting structure according to claim 1, wherein the wall surface is a ceiling surface constituting a building. The magnetostrictive actuator mounting structure according to claim 1, wherein the wall surface is a wall surface constituting furniture. The magnetostrictive actuator mounting structure according to claim 1, wherein the wall surface is a wall surface constituting household equipment.

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