JP2014049853A - Electro-acoustic transducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electro-acoustic transducer capable of converting an electric signal into an acoustic signal of high sound quality using a super-magnetostrictive vibrator.SOLUTION: A super-magnetostrictive vibrator housing 20 internally houses a super-magnetostrictive vibrator. A holder 30 holds the super-magnetostrictive vibrator housing 20, and an annular member 41, which is a vibration transmission body, is attached to the holder 30 in a fixed state. A housing body 10 includes a housing recess 11 for housing a super-magnetostrictive vibrator assembly 50 constituted by the holder 30 that holds the super-magnetostrictive vibrator housing 20 and the annular member 41 attached to the holder 30. The super-magnetostrictive vibrator housing 20 and the holder 30 are in a floating state relative to the annular member 41 and the housing body 10.

Description

  The present invention relates to an electroacoustic transducer that converts an electrical signal into an acoustic signal using a giant magnetostrictive vibration element.

  An electroacoustic transducer that converts an electrical signal into an acoustic signal using a giant magnetostrictive vibration element has been put into practical use. As an example, Patent Document 1 describes an electroacoustic transducer (magnetostrictive speaker) using a giant magnetostrictive vibration element.

JP 2005-176055 A

  The giant magnetostrictive vibration element includes a giant magnetostrictive material and a coil that applies magnetism to the giant magnetostrictive material. When a current is passed through the coil and magnetism is applied to the giant magnetostrictive material, the giant magnetostrictive material expands and contracts. As a result, the giant magnetostrictive vibration element vibrates very minutely. The giant magnetostrictive vibration element has a short length of expansion and contraction, but can transmit a very strong force to a member in contact with the giant magnetostrictive vibration element.

  Higher sound quality is also demanded for electroacoustic transducers using giant magnetostrictive vibration elements. In order to improve the sound quality, it is important how the giant magnetostrictive vibration element is fixed and how the strong force generated by the giant magnetostrictive vibration element is transmitted to a member that generates sound. If the fixing structure of the giant magnetostrictive vibration element and the force transmission structure generated by the giant magnetostrictive vibration element are not appropriate, vibration transmission loss occurs and a high-quality sound signal cannot be generated.

  In order to meet such a demand, an object of the present invention is to provide an electroacoustic transducer capable of converting an electrical signal into a high-quality acoustic signal using a giant magnetostrictive vibration element.

  In order to solve the above-described problems of the prior art, the present invention includes a giant magnetostrictive vibration element (21) housed therein and an electric signal supplied to the giant magnetostrictive vibration element. A super magnetostrictive vibration element container (20) having a vibration part (23) that vibrates when the vibration is transmitted, a holder (30) that holds the super magnetostrictive vibration element container, and an elastic member ( 42-44), the vibration transmitting body (40) which is mounted in a fitted state and transmits the vibration of the vibration section, the holder for holding the giant magnetostrictive vibration element storage body, and the holder mounted on the holder. A giant magnetostrictive vibration element assembly (50) made of a vibration transmitting body is housed, and a housing body (10) that generates a sound by transmitting vibrations transmitted to the vibration transmitting body. The body and the holder To provide an electroacoustic transducer, characterized in that in a floating state with respect to the dynamic transmission body and the housing body.

  In the above electroacoustic transducer, it is preferable that the holder and the vibration transmitting body are each made of metal.

  In the above electroacoustic transducer, it is preferable that the holder is made of aluminum or zinc, and the vibration transmitting body is made of brass.

  In the above electroacoustic transducer, the holder is formed with a circular portion (31) having a circular opening (31a) and a housing recess (322) that projects from the circular portion and houses the giant magnetostrictive vibration element housing. And the vibration transmitting body is formed by a ring-shaped member (41), and the ring-shaped member is fitted into the circular portion through the elastic member in a fitted state. It is preferable.

  In the above electroacoustic transducer, the storage body is formed of a plate material, and the storage body is formed on one surface side of the plate material and has a storage recess (11) for storing the giant magnetostrictive vibration element assembly. The storage recess is preferably covered with a lid (18), and the ring-shaped member is preferably sandwiched between the bottom surface of the storage recess and the back surface of the lid.

  In the above electroacoustic transducer, it is preferable that the giant magnetostrictive vibration element housing and the holder are not in contact with both the bottom surface of the housing recess and the back surface of the lid.

  According to the electroacoustic transducer of the present invention, an electrical signal can be converted into a high-quality acoustic signal using a giant magnetostrictive vibration element.

It is a perspective view which shows the electroacoustic transducer of one Embodiment. It is a top view which shows an example structure of the giant magnetostrictive vibration element storage body used with the electroacoustic transducer of one Embodiment. It is a perspective view which shows an example structure of the holder for hold | maintaining the giant magnetostrictive vibration element storage body shown in FIG. FIG. 4 is a perspective view showing a state in which the giant magnetostrictive vibration element housing shown in FIG. 2 is attached to the holder shown in FIG. It is a perspective view which shows an example structure of the vibration transmission body used with the electroacoustic transducer of one Embodiment. It is a perspective view which shows the ring-shaped member which comprises the vibration transmission body shown in FIG. FIG. 6 is a perspective view showing a giant magnetostrictive vibration element assembly in which the giant magnetostrictive vibration element housing shown in FIG. 2 is attached to the holder shown in FIG. 3 and the vibration transmitting body shown in FIG. 5 is attached to the holder. It is sectional drawing of the giant magnetostrictive vibration element assembly shown in FIG. It is a perspective view which shows an example structure of the storage body used with the electroacoustic transducer of one Embodiment. FIG. 10 is a perspective view showing a state where the giant magnetostrictive vibration element assembly is housed in the housing recess of the housing body shown in FIG. 9. It is a perspective view which shows the state which accommodated the giant magnetostrictive vibration element assembly in the storage recessed part of a storage body, and closed the lid | cover. It is a fragmentary sectional view of the storage body which stores the giant magnetostrictive vibration element assembly. It is a top view which shows the modification of a giant magnetostrictive vibration element assembly. It is sectional drawing which shows the modification of a ring-shaped member. It is a perspective view which shows the example of the usage pattern which uses the electroacoustic transducer of one Embodiment.

  Hereinafter, an electroacoustic transducer according to an embodiment will be described with reference to the accompanying drawings. As shown in FIG. 1, the electroacoustic transducer 100 of one Embodiment is provided with the storage body 10 formed with the solid board | plate material as an example. The storage body 10 stores therein a giant magnetostrictive vibration element assembly including a giant magnetostrictive vibration element to be described later. The giant magnetostrictive vibration element assembly is a vibration generating unit that generates vibration in response to an electrical signal.

  A cord 24 for supplying an electric signal corresponding to the acoustic signal to the giant magnetostrictive vibration element assembly is drawn out from the storage body 10. The cord 24 is connected to an amplifier not shown.

  A specific structure of the giant magnetostrictive vibration element assembly housed in the housing body 10 will be described. In FIG. 2, the giant magnetostrictive vibration element housing 20 houses a giant magnetostrictive vibration element 21 (shown in FIG. 8). The giant magnetostrictive vibration element housing 20 is formed in a cylindrical shape. A cord 24 connected to the giant magnetostrictive vibration element 21 is drawn from the rear end of the giant magnetostrictive vibration element housing 20. A male screw 22 is formed on a substantially half surface portion of the giant magnetostrictive vibration element housing 20 on the front end side.

  A vibration part 23 to which the vibration of the giant magnetostrictive vibration element 21 is transmitted protrudes from the tip of the giant magnetostrictive vibration element housing 20. Accordingly, when an electric signal is supplied to the giant magnetostrictive vibration element housing 20 via the cord 24, only the vibration part 23 vibrates in appearance.

  FIG. 3 shows a holder 30 for holding the giant magnetostrictive vibration element housing 20 shown in FIG. As shown in FIG. 3, the holder 30 includes a circular portion 31 having a circular opening 31 a and a protruding portion 32 protruding from the circular portion 31. Since the holder 30 needs to hold the giant magnetostrictive vibration element housing 20 and fix the giant magnetostrictive vibration element 21, the holder 30 is preferably formed of a metal having a large mass. In consideration of ease of processing and the like, the holder 30 is preferably formed of aluminum or zinc die casting.

  A trapezoidal convex portion 321 is formed at each of the upper and lower portions of FIG. An accommodating recess 322 for accommodating the giant magnetostrictive vibration element accommodating body 20 is formed at the center in the width direction of the protruding portion 32. A female screw 323 is formed on the inner peripheral surface of approximately half of the accommodating recess 322 on the circular portion 31 side. The female screw 323 can be formed by threading after the circular portion 31 and the protruding portion 32 are formed by die casting.

  When the giant magnetostrictive vibration element housing body 20 enters the housing recess 322 and rotates, the male screw 22 is screwed into the female screw 323 so that the giant magnetostrictive vibration element housing body 20 is firmly integrated with the holder 30. FIG. 4 shows a state in which the giant magnetostrictive vibration element housing 20 is housed in the housing recess 322 and the giant magnetostrictive vibration element housing 20 and the holder 30 are integrated.

  A vibration transmission body 40 shown in FIG. 5 is mounted in the opening 31 a of the circular portion 31. The vibration transmitting body 40 has a ring-shaped member 41 shown in FIG. As shown in FIG. 6, here, two grooves 411 formed in the circumferential direction are formed on the outer peripheral surface of the ring-shaped member 41. As shown in FIG. 5, an O-ring 42 made of rubber is fitted in the groove 411. The ring-shaped member 41 is preferably a metal, and most preferably brass. The O-ring 42 is not limited to rubber as long as it is an elastic member, but rubber is preferable.

  When the vibration transmitting body 40 shown in FIG. 5 is mounted in the opening 31a, the state shown in FIG. 7 is obtained. An assembly in which the giant magnetostrictive vibration element housing 20 shown in FIG. 7 is attached to the holder 30 and the vibration transmitting body 40 is attached to the holder 30 is referred to as a giant magnetostrictive vibration element assembly 50. Actually, when assembling the giant magnetostrictive vibration element assembly 50, it is preferable to attach the vibration transmitting body 40 to the holder 30 and then attach the giant magnetostrictive vibration element storage body 20 to the holder 30.

  FIG. 8 shows a state where the projection 32 is cut so as to pass through the top of the giant magnetostrictive vibration element housing 20 at the center in the width direction of the protrusion 32 in FIG. As can be seen from FIG. 8, the ring-shaped member 41 with the O-ring 42 attached is a substantially circular inner peripheral surface formed by the inner peripheral surface of the circular portion 31 and the tip portion of the giant magnetostrictive vibration element storage body 20. It is sandwiched between. That is, the vibration transmitting body 40 is in a state of being fitted inside the circular portion 31 of the holder 30.

  In this state, the vibration part 23 protruding from the giant magnetostrictive vibration element housing 20 is in contact with only the ring-shaped member 41. Since the giant magnetostrictive vibration element housing 20 is firmly held by the holder 30 and the ring-shaped member 41 is in a state of being fitted to the circular portion 31 via the O-ring 42, the O-ring 42 has the giant magnetostrictive vibration. The element housing 20 is biased. Therefore, the vibration of the vibration part 23 is transmitted to the ring-shaped member 41 with very little loss.

  As can be seen from FIG. 8, the height of the ring-shaped member 41 is higher than the height of the circular portion 31 of the holder 30. Further, the height of the ring-shaped member 41 is the distance between the surfaces corresponding to the upper bases of the opposing convex portions 321, that is, the upper flat surface of the upper convex portion 321 and the lower convex portion 321 in FIG. 3. It is higher than the height of the protrusion 32, which is the distance from the lower flat surface. Therefore, the giant magnetostrictive vibration element housing 20 and the holder 30 are in a floating state with respect to the ring-shaped member 41.

  The above-described giant magnetostrictive vibration element assembly 50 shown in FIG. 7 is housed in the housing 10 as follows. FIG. 9 shows the back surface of the housing 10 that is a plate material. An upper inclined surface 10a, a lower inclined surface 10b, and left and right inclined surfaces 10c and 10d are formed on the rear surface side of the storage body 10. A storage recess 11 for storing the giant magnetostrictive vibration element assembly 50 is formed in a central portion surrounded by the inclined surfaces 10a to 10d.

  A stepped portion 12 is formed in the storage recess 11 to place a lid 18 (shown in FIG. 11) for covering the opening of the storage recess 11. The height of the stepped portion 12 and the thickness of the lid 18 are set so that the surface around the opening of the storage recess 11 and the lid 18 are flush with the stepped portion 12 in the state where the lid 18 is placed. .

  Bolts not shown here are attached to the four corners of the storage recess 11 in the stepped portion 12 and the portion closer to the upper inclined surface 10a side than the center of the upper inclined surface 10a and the lower inclined surface 10b. A hole 13 is formed. A demon nut 19N is embedded in the hole 13. The bolt is preferably a hexagon socket head cap screw.

  The hole 13 provided in the portion closer to the upper inclined surface 10a side than the center of the upper inclined surface 10a and the lower inclined surface 10b is not essential. However, since it is better to fix the lid 18 to the storage body 10 at a position close to the giant magnetostrictive vibration element assembly 50, a portion closer to the upper inclined surface 10a side than the center of the upper inclined surface 10a and the lower inclined surface 10b. It is preferable to provide the hole 13 provided in the.

  A circular recess 14 is formed on the bottom surface of the storage recess 11 near the upper inclined surface 10a. A circular convex portion 15 is formed in the central portion of the concave portion 14. The upper surface of the convex portion 15 protrudes from the bottom surface of the storage concave portion 11. Since the circular convex portion 15 is formed in the circular concave portion 14, the periphery of the convex portion 15 is a ring-shaped concave portion. The ring-shaped recess is provided to position the ring-shaped member 41 by positioning the lower surface side of the ring-shaped member 41 in the recess. A rectangular recess 16 extending in a direction connecting the upper inclined surface 10a and the lower inclined surface 10b is formed on the bottom surface of the storage recess 11. The recess 16 is connected to the recess 14. However, the depth of the recess 16 is deeper than the depth of the recess 14.

  A through hole 17 that penetrates the inner wall of the storage recess 11 and the lower inclined surface 10 b is formed in a portion of the storage body 10 that is closer to the lower inclined surface 10 b than the storage recess 11.

  FIG. 10 shows a state where the giant magnetostrictive vibration element assembly 50 is housed in the housing recess 11. In the giant magnetostrictive vibration element assembly 50, the lower surface of the ring-shaped member 41 abuts on the bottom surface of the concave portion 14, and the convex portion 321 and the concave portion 16 of the protruding portion 32 face each other in a non-contact manner. It is assumed that the bottom surface of the giant magnetostrictive vibration element assembly 50 in FIG. The cord 24 is drawn out through the through hole 17.

  FIG. 11 shows a state in which the lid 18 is placed on the stepped portion 12 in the state of FIG. As described above, the demon nut 19N is attached to each hole 13, and the lid 18 is fixed by tightening the hexagon socket bolt 19B to the demon nut 19N.

  FIG. 12 is a partial cross-sectional view of FIG. 11 taken at a position away from the top of the giant magnetostrictive vibration element storage body 20 in the direction connecting the upper inclined surface 10a and the lower inclined surface 10b. As shown in FIG. 12, the lower surface of the ring-shaped member 41 is in contact with the bottom surface of the recess 14, and the upper surface of the ring-shaped member 41 is in contact with the back surface of the lid 18. Since the lid 18 is firmly fixed to the back surface of the storage body 10 with hexagon socket bolts 19B, the ring-shaped member 41 is firmly sandwiched between the bottom surface of the storage recess 11 (recess 14) and the back surface of the lid 18. It is in a state.

  In FIG. 12, the ring-shaped member 41 is positioned in the ring-shaped recess around the protrusion 15 with the outer periphery of the ring-shaped member 41 approaching the outer periphery of the recess 14. The diameter of the convex portion 15 may be made larger than that in the state of FIG. 12 to narrow the width of the ring-shaped concave portion. In this case, the ring-shaped member 41 may be positioned in the ring-shaped concave portion by bringing the inner peripheral side of the ring-shaped member 41 close to the convex portion 15 side.

  Also, as shown in FIG. 12, since the recess 16 is formed on the bottom surface of the storage recess 11, the lower surface of the protrusion 32 of the holder 30 is not in contact with the bottom surface of the storage recess 11. Since a recess 181 is formed on the back surface of the lid 18 facing the protruding portion 32, the upper surface of the protruding portion 32 is not in contact with the back surface of the lid 18. The lower surface of the circular portion 31 is also not in contact with the bottom surface of the storage recess 11, and the upper surface of the circular portion 31 is also not in contact with the back surface of the lid 18. Accordingly, the giant magnetostrictive vibration element storage body 20 and the holder 30 are in a floating state with respect to the storage body 10 and the lid 18.

  When an electric signal is supplied to the giant magnetostrictive vibration element housing 20 via the cord 24, the giant magnetostrictive vibration element 21 vibrates. When the giant magnetostrictive vibration element 21 vibrates, the vibration portion 23 protruding from the giant magnetostrictive vibration element housing 20 vibrates. The vibration of the vibration part 23 is transmitted to the ring-shaped member 41. As shown in FIG. 12, the direction of vibration transmitted from the vibrating portion 23 to the ring-shaped member 41 is the direction of the arrow D1. The direction of the arrow D1 is a direction parallel to the surface of the storage body 10.

  Since the ring-shaped member 41 is in contact with only the housing 10 and the lid 18, the vibration in the direction of arrow D1 is converted into vibration in the direction of arrow D2 orthogonal to the direction of arrow D1, as shown in FIG. The The direction of the arrow D2 is a direction orthogonal to the surface of the storage body 10 and the surface of the lid 18. Therefore, the vibration of the vibration part 23 (the giant magnetostrictive vibration element 21) is transmitted from the vibration part 23 to the ring-shaped member 41 and from the ring-shaped member 41 to the housing 10 and the lid 18 with very little loss. Will be.

  Thereby, in the electroacoustic transducer 100 of the present embodiment, the plate material constituting the housing body 10 of FIG. 1 vibrates very efficiently, and high-quality sound is output from the front surface (and the back surface) of the plate material. The sound reproduced by the electroacoustic transducer 100 is so-called by the device for fixing the giant magnetostrictive vibration element 21 (giant magnetostrictive vibration element storage body 20) and the structure for transmitting the force generated by the giant magnetostrictive vibration element 21. High sound quality with almost no chatter sound.

  The electroacoustic transducer 100 according to the present embodiment can employ various modifications in addition to the configuration described above. In the configuration described above, the ring-shaped member 41 (vibration transmitting body 40) with the O-ring 42 attached is fitted to the circular portion 31 of the holder 30, but an elastic member is not provided on the entire circumference of the ring-shaped member 41. May be.

  For example, as shown in FIG. 13A, the ring-shaped member 41 is attached by attaching an elastic member 43 such as an elastic sheet to the surface of the ring-shaped member 41 on the side opposite to the side on which the vibrating portion 23 abuts. It is good also as a fitting state with respect to the circular part 31. FIG. As shown in FIG. 13B, the ring-shaped member 41 may be fitted to the circular portion 31 by sandwiching four elastic members 44 between the circular portion 31 and the ring-shaped member 41. . As the elastic members 43 and 44, a spring may be used in addition to rubber.

  The shape of the ring-shaped member 41 can be changed as appropriate. In FIG. 14, the cross-sectional views shown in (a) to (d) show examples of the shape of the ring-shaped member 41. Although the shape of the ring-shaped member 41 is different, here, for convenience, the same reference numerals are allotted to (a) to (d) of FIG.

  FIG. 14A shows the shape shown in FIG. 6, and the groove 411 is omitted here for the sake of simplicity. In FIG. 14B, the lower surface side of the ring-shaped member 41 that is the side facing the bottom surface of the storage recess 11 is made thicker than the upper surface side of the ring-shaped member 41 that is the side facing the back surface of the lid 18. It is an example. In this way, more sound can be output from the front side than the back side of the storage body 10.

  14C and 14D are examples in which the central portion in the vertical direction of the ring-shaped member 41 with which the vibrating portion 23 abuts is thickened. In this way, the vibration of the vibration part 23 can be easily transmitted to the ring-shaped member 41, and the vibration transmitted to the ring-shaped member 41 can be easily transmitted to the storage body 10 and the lid 18.

  The shape of the ring-shaped member 41 is not limited to a circle and may be other than a circle such as a polygon. However, the circular shape is easier to manufacture, and the circular shape is preferable in terms of sound quality.

  By the way, in order to improve sound quality, in particular, in order to enhance bass, a plurality of giant magnetostrictive vibration elements 21 may be arranged in series to constitute the giant magnetostrictive vibration element housing 20. In this case, the total length of the giant magnetostrictive vibration element housing 20 is increased. As can be seen from FIG. 10, even if the giant magnetostrictive vibration element housing 20 becomes longer, the giant magnetostrictive vibration element assembly 50 housed in the housing recess 11 only becomes longer toward the lower inclined surface 10b. The electroacoustic transducer 100 does not become thick. Regardless of the length of the giant magnetostrictive vibration element container 20, the thickness of the container 10 can be reduced.

  Here, an example of a usage pattern of the electroacoustic transducer 100 will be described. As shown in FIG. 15A, the electroacoustic transducer 100 incorporating the giant magnetostrictive vibration element assembly 50 is brought into a nearly vertical state by the stopper 101, and sound is generated from the electroacoustic transducer 100. The arrows in FIG. 15 conceptually indicate the sound output from the electroacoustic transducer 100.

  FIG. 15B is an example in which the electroacoustic transducer 100, the bottom plate 102, the upper plate 102, and the rear plate 104 are assembled into a box shape having two open surfaces. It is also possible to configure the rear plate 104 with the electroacoustic transducer 100. In FIGS. 15A and 15B, the code 24 is not shown. In addition, it is also conceivable to use the electroacoustic transducer 100 while being hung on a wall.

  The present invention is not limited to the embodiment described above, and various modifications can be made without departing from the scope of the present invention. The storage body 10 is preferably a solid plate material, but plywood may be used. The material of the storage body 10 is preferably wood, but may be other than wood.

DESCRIPTION OF SYMBOLS 10 Storage body 11 Storage recessed part 18 Cover 20 Super magnetostrictive vibration element storage body 21 Super magnetostrictive vibration element 23 Vibrating part 24 Code 30 Holder 31 Circular part 31a Opening 32 Projection part 40 Vibration transmitting body 41 Ring-shaped member 42 O-ring (elastic member)
43, 44 Elastic member 50 Giant magnetostrictive vibration element assembly 100 Electroacoustic transducer 322 Housing recess

Claims (6)

A giant magnetostrictive vibration element housing having a vibration part that houses a giant magnetostrictive vibration element and vibrates by transmitting vibrations of the giant magnetostrictive vibration element generated when an electric signal is supplied to the giant magnetostrictive vibration element. ,
A holder for holding the giant magnetostrictive vibration element housing;
A vibration transmitting body that is mounted in an engaged state with respect to the holder via an elastic member, and that transmits vibrations of the vibrating portion;
A giant magnetostrictive vibration element assembly comprising a holder for holding the giant magnetostrictive vibration element housing and the vibration transmitting body mounted on the holder is housed, and the vibration transmitted to the vibration transmitting body is transmitted to generate sound. And a storage body
With
The electroacoustic transducer, wherein the giant magnetostrictive vibration element storage body and the holder are in a floating state with respect to the vibration transmission body and the storage body.   2. The electroacoustic transducer according to claim 1, wherein the holder and the vibration transmitting body are made of metal.   The electroacoustic transducer according to claim 2, wherein the holder is made of aluminum or zinc, and the vibration transmitting body is made of brass. The holder includes a circular portion having a circular opening, and a protruding portion that protrudes from the circular portion and has an accommodating recess that accommodates the giant magnetostrictive vibration element accommodating body,
The vibration transmission body is formed by a ring-shaped member, and the ring-shaped member is mounted in a fitted state inside the circular portion via the elastic member. The electroacoustic transducer according to Item 1. The storage body is formed of a plate material,
The storage body is formed on one surface side of the plate member, and has a storage recess for storing the giant magnetostrictive vibration element assembly.
The storage recess is covered by a lid;
The electroacoustic transducer according to any one of claims 1 to 4, wherein the ring-shaped member is sandwiched between a bottom surface of the housing recess and a back surface of the lid.   6. The electroacoustic transducer according to claim 5, wherein the giant magnetostrictive vibration element housing and the holder are not in contact with both the bottom surface of the housing recess and the back surface of the lid.

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