JP2005191776A - Acoustic device and speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acoustic device attachable and removable easily at a desired position. <P>SOLUTION: The acoustic device includes a pillar-shaped magnetostrictor 51 having one edge fixed to a fixing end of a separation plate 22 on the edge side and the other edge fixed to a free end thereof and expanding and shrinking in an axial direction, a driving coil 54 for generating a magnetic field for expanding and shrinking the pillar-shaped magnetostrictor 51 through a driving current based on the acoustic signal, and a bias magnet 53 located on the other edge side of the pillar-shaped magnetostrictor 51 for applying a bias magnetic field to the pillar-shaped magnetostrictor 51. Under a condition, where the bias magnet 53 is put in contact with a glass plate 7, a magnet body 8 is attracted by the bias magnet 53 through the glass plate 7 so as to be mounted on the glass plate 7 in this structure. At the same time, the oscillation caused by the expansion and shrinkage of the pillar-shaped magnetostrictor 51 can be transmitted through the glass plate 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an acoustic device and a speaker using a magnetostrictive element.

  As this type of acoustic device, an acoustic device disclosed in Japanese Patent Laid-Open No. 9-261797 is known. This acoustic device includes a columnar magnetostrictive element and a drive coil wound around a bobbin with the columnar magnetostrictive element as the center. In this case, the columnar magnetostrictive element is disposed such that one end thereof is in contact with the disk-shaped magnetic body and the other end is in contact with the end of the magnetic member. The magnetic member has a flange, and an elastic member is inserted between the flange and the case. Therefore, the magnetic member is biased toward the columnar magnetostrictive element by the inserted elastic member, so that the magnetic member is maintained in a state of being able to advance and retract in a direction along the vibration direction of the columnar magnetostrictive element. As a result, the disk-shaped magnetic body, the columnar magnetostrictive element, and the magnetic member are integrally connected in a state that allows vibration of the columnar magnetostrictive element.

  In this acoustic device, when a drive current based on an acoustic signal is supplied, the drive coil generates a magnetic field oriented along the axial direction of the columnar magnetostrictive element. At this time, the columnar magnetostrictive element expands and contracts in the axial direction by applying the generated magnetic field. For this reason, a magnetic member vibrates in the axial direction according to expansion and contraction of the columnar magnetostrictive element. Therefore, by pressing this magnetic member against a vibrating body such as a diaphragm, the vibration is transmitted to the vibrating body, and sound is output from the vibrating body.

As this type of speaker, a speaker disclosed in Japanese Patent Laid-Open No. 10-145892 is known. In this speaker, one end of a columnar magnetostrictive element (giant magnetostrictive rod) is supported by a disk-shaped yoke, thereby forming a fixed end that cannot move in the axial direction. An actuator rod is integrally connected to the other end of the columnar magnetostrictive element via a movable yoke. In this case, the diaphragm of the actuator rod is fixed to the tip of the actuator rod via the attachment disk. Therefore, in this speaker, the vibration of the actuator rod is transmitted to the diaphragm, and sound is output from the diaphragm.
JP-A-9-261797 (page 3, FIG. 1) Japanese Patent Laid-Open No. 10-145892 (page 3, FIG. 1)

  However, the above-described acoustic device has the following problems. That is, in this acoustic device, sound is output from the diaphragm by pressing the magnetic member against the diaphragm. Therefore, in order to output sound, a method of pressing the magnetic member against the diaphragm by a human hand (hereinafter also referred to as “first method”), a method of using a jig for pressing and fixing the magnetic member ( Hereinafter, also referred to as “second method”) or a method of fixing the magnetic member to the diaphragm using a screw or an adhesive (in this method, the inertial mass of the acoustic device is used as a force to press the diaphragm) In the following, it is conceivable to adopt the “third method”). In this case, the first method is somewhat complicated because it is necessary to continue holding the acoustic device while outputting the sound. Further, in the second method, it is complicated for each user to produce a jig, and using a special jig as an accessory for an audio device increases the manufacturing cost. In the third method, since the magnetic member is fixed to the diaphragm with screws or an adhesive, it is difficult to change the mounting position or change to another diaphragm after being fixed once. Furthermore, the use of screws or adhesives may cause holes in the diaphragm or adhesion of adhesives.

  On the other hand, the conventional speaker has the following problems. That is, in this speaker, a columnar magnetostrictive element or the like is fixed to the diaphragm via the mounting disk. Therefore, there is a problem that it is difficult to change to another arbitrary diaphragm (vibration transmission object) and enjoy different sound quality and design changes.

  This invention is made | formed in view of this subject, and it aims at providing the audio equipment which can be easily attached or detached to arbitrary places. It is another object of the present invention to provide a speaker that can be easily replaced with an arbitrary vibration transmission object.

  In order to achieve the above object, the acoustic device according to the present invention has a columnar shape in which a stopper is disposed on one end side, the one end is defined as a fixed end, and the other end is defined as a free end and extends and contracts along the axial direction. A magnetostrictive element; a magnetic field generating unit configured to generate a magnetic field for expanding and contracting the columnar magnetostrictive element by a drive current based on an acoustic signal; and a bias magnetic field applied to the columnar magnetostrictive element disposed on the other end side of the columnar magnetostrictive element The permanent magnet is attached to the vibration transmission target body by adsorbing the magnetic body to the permanent magnet via the vibration transmission target body in a state where the permanent magnet is in contact with the vibration transmission target body. It is configured to be capable of transmitting vibration due to expansion and contraction of the columnar magnetostrictive element to the vibration transmission target body.

  Further, the acoustic device according to the present invention is a columnar magnetostrictive element that is provided with a stopper on one end side, the one end is defined as a fixed end, and the other end is defined as a free end, and expands and contracts along the axial direction. A magnetic field generator for generating a magnetic field for expanding and contracting the columnar magnetostrictive element by a driving current based on an acoustic signal; and a magnetic body disposed on the other end side of the columnar magnetostrictive element; A structure that can be attached to the vibration transmission target body by adsorbing the magnetic body through the vibration transmission target body to a permanent magnet capable of applying a bias magnetic field to the columnar magnetostrictive element in a state of contact with the body. In addition, vibration due to expansion and contraction of the columnar magnetostrictive element can be transmitted to the vibration transmission target body.

  The speaker according to the present invention includes a columnar magnetostrictive element that is provided with a stopper on one end side, the one end is defined as a fixed end, the other end is defined as a free end, and expands and contracts along an axial direction. A magnetic field generating section that generates a magnetic field for expanding and contracting the columnar magnetostrictive element by a driving current based on a signal; a permanent magnet that is disposed on the other end side of the columnar magnetostrictive element and applies a bias magnetic field to the columnar magnetostrictive element; A vibration transmission object disposed with one surface in contact with the permanent magnet, and disposed on the other surface of the vibration transmission object and attracted to the permanent magnet via the vibration transmission object. And a magnetic body that is configured to transmit vibration caused by expansion and contraction of the columnar magnetostrictive element to the vibration transmission target body.

  The speaker according to the present invention includes a columnar magnetostrictive element that is provided with a stopper on one end side, the one end is defined as a fixed end, the other end is defined as a free end, and expands and contracts along an axial direction. A magnetic field generator for generating a magnetic field for expanding and contracting the columnar magnetostrictive element by a driving current based on a signal, a magnetic body disposed on the other end side of the columnar magnetostrictive element, and one surface of the magnetic body contacting each other A vibration transmission target body arranged in a state, the magnetic transmission body being attached to the other surface of the vibration transmission target body, and adsorbing the magnetic body through the vibration transmission target body, and a bias magnetic field applied to the columnar magnetostrictive element And a permanent magnet for applying a vibration to the vibration transmission object.

  In the acoustic device according to the present invention, a stopper is disposed on one end side of the columnar magnetostrictive element, and a permanent magnet that applies a bias magnetic field to the columnar magnetostrictive element is disposed on the other end side of the columnar magnetostrictive element. For this reason, in a state where the permanent magnet is in contact with the vibration transmission target body, the acoustic device is fixed to the vibration transmission target body by adsorbing the magnetic body to the permanent magnet via the vibration transmission target body. At the same time, vibration due to expansion and contraction of the columnar magnetostrictive element is transmitted to the vibration transmission object. Therefore, although it is a simple fixing method in which a magnetic material is attracted to a permanent magnet of an acoustic device through a vibration transmission target body, sound can be generated at any place (vibration transmission target body) where the permanent magnet and the magnetic body can be attracted. Equipment can be easily attached and detached.

  In the acoustic device according to the present invention, a stopper is disposed on one end side of the columnar magnetostrictive element, and a magnetic body is disposed on the other end side of the columnar magnetostrictive element. For this reason, in a state where the magnetic body is in contact with the vibration transmission target body, the acoustic device is fixed to the vibration transmission target body by adsorbing the magnetic body to the permanent magnet via the vibration transmission target body. At the same time, vibration due to expansion and contraction of the columnar magnetostrictive element is transmitted to the vibration transmission object. Therefore, although it is a simple fixing method in which the magnetic body of the acoustic device is attracted to the permanent magnet through the vibration transmission target body, the sound can be generated at any place (vibration transmission target body) where the magnetic body and the permanent magnet can be attracted. Equipment can be easily attached and detached.

  In the speaker according to the present invention, a stopper is disposed on one end side of the columnar magnetostrictive element, and a permanent magnet that applies a bias magnetic field to the columnar magnetostrictive element is disposed on the other end side of the columnar magnetostrictive element. Therefore, in a state where the permanent magnet is in contact with the vibration transmission target body, the columnar magnetostrictive element or the like is fixed to the vibration transmission target body by attracting the magnetic body to the permanent magnet via the vibration transmission target body. In addition, vibration caused by expansion and contraction of the columnar magnetostrictive element is transmitted to the vibration transmission object. Therefore, it is a simple fixing method in which the magnetic material is attracted to the permanent magnet through the vibration transmission target body, but it can be attached to any diaphragm (vibration transmission target object such as a casing) on which the permanent magnet can attract the magnetic body. A columnar magnetostrictive element or the like can be easily fixed. As a result, since it can be easily replaced with an arbitrary diaphragm, various sound quality and design changes can be fully enjoyed.

  In the speaker according to the present invention, a stopper is disposed on one end side of the columnar magnetostrictive element, and a magnetic body is disposed on the other end side of the columnar magnetostrictive element. Therefore, in a state where the magnetic body is in contact with the vibration transmission target body, the columnar magnetostrictive element or the like is fixed to the vibration transmission target body by attracting the magnetic body to the permanent magnet via the vibration transmission target body. In addition, vibration caused by expansion and contraction of the columnar magnetostrictive element is transmitted to the vibration transmission object. Therefore, it is a simple fixing method in which the magnetic material is attracted to the permanent magnet through the vibration transmission target body, but it can be attached to any diaphragm (vibration transmission target object such as a casing) on which the permanent magnet can attract the magnetic body. A columnar magnetostrictive element or the like can be easily fixed. As a result, since it can be easily replaced with an arbitrary diaphragm, various sound quality and design changes can be fully enjoyed.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an audio device and a speaker according to the invention will be described with reference to the accompanying drawings.

  Initially, the structure of the pencil type speaker 1 to which the audio equipment which concerns on this invention is applied is demonstrated with reference to drawings.

  As shown in FIG. 1, the pencil-type speaker 1 includes a cylindrical housing 2, an acoustic signal amplification unit 3, a power supply unit 4, and a vibration conversion unit 5, and a bias magnet 53 (to be described later) at the tip of the pencil speaker 1 is a vibration transmission target. An acoustic signal can be output when pressed against a plate as a body, or when the bias magnet 53 attracts the magnetic body 8 via, for example, a glass plate 7 as a vibration transmission target body. Yes. As shown in the figure, the housing 2 includes an upper housing 2a and a lower housing 2b made of synthetic resin, and is formed at the end of each of the housings 2a and 2b. As a whole, it is configured in a long and thin pencil shape by being fitted and integrally connected by the fitting portion. Further, the upper casing 2a is provided with a partition plate 21. The acoustic signal amplifying unit 3 is housed in an internal space on the rear end side partitioned by the partition plate 21, and the power source unit 4 is connected to the partition plate 21. 21 is housed in the internal space on the tip side divided by 21. On the other hand, a partition plate 22 that partitions the power supply unit 4 and the vibration conversion unit 5 is fixed to the lower housing 2b.

  As shown in FIG. 2, the acoustic signal amplifying unit 3 amplifies an acoustic signal input from the outside via the acoustic signal cable 6 and outputs a driving current generated to the driving coil 54 via a connection cable (not shown). . Further, as shown in FIG. 1, the acoustic signal amplifying unit 3 includes an amplifier board 31 disposed on the rear end side of the upper housing 2a. In the amplifier board 31, as shown in FIG. A power switch 32 and an acoustic signal input connector 33 are mounted. In this case, as shown in the figure, the power switch 32 includes a knob 34 that can be turned on / off by switching operation. The acoustic signal input connector 33 is configured as a jack into which the plug 61 of the acoustic signal cable 6 for inputting an acoustic signal from the outside can be inserted, as shown in FIG.

  As shown in FIGS. 1 and 2, the power supply unit 4 includes, for example, three dry batteries 41, 41, 41, a dry battery terminal 42 fixed to the partition plate 21, and a dry battery terminal 43 fixed to the partition plate 22. The power is supplied to the acoustic signal amplifying unit 3 via a connection cable connected to the dry battery terminals 42 and 43. In this case, the dry battery 41 is taken in and out from the opening on the tip end side of the upper housing 2a in a state separated from the lower housing 2b with the fitting portion removed.

  The vibration converting unit 5 is disposed in the internal space of the lower housing 2b, and includes a columnar magnetostrictive element 51, bias magnets 52 and 53, and a drive coil 54 as shown in FIGS. The columnar magnetostrictive element 51 functions as an element that expands and contracts in the axial direction when a magnetic field is applied in a direction along the axial direction, and converts magnetic field fluctuations into mechanical vibration. The columnar magnetostrictive element 51 is, for example, formed of a super magnetostrictive material having a central composition of Tb0.34-Dy0.66-Fe1.90 that causes a large displacement of about 1500 ppm to 2000 ppm with respect to the axial direction in a magnetic field. Has been. Note that one end of the columnar magnetostrictive element 51 on the partition plate 22 side corresponds to a fixed end in the present invention, and the other end on the bias magnet 53 side corresponds to a free end in the present invention.

  The bias magnet 52 is, for example, a permanent magnet formed in a disk shape having a diameter substantially the same as the diameter of the columnar magnetostrictive element 51, and one end surface of the bias magnet 52 is a one on the upper housing 2 a side of the columnar magnetostrictive element 51. It is fixed in a state where it is in contact with the end surface, and is fixed in a state where the other end surface is in contact with the partition plate 22. The bias magnet 53 (permanent magnet in the present invention) is, for example, a permanent magnet formed in a disk shape whose diameter is slightly larger than the diameter of the housing 2, and its rear end surface is the upper housing in the columnar magnetostrictive element 51. It is fixed in contact with the other end surface opposite to 2a. In this case, the bias magnets 52 and 53 apply a bias magnetic field so that the columnar magnetostrictive element 51 can be operated at an operating point that expands and contracts (vibrates) substantially linearly with respect to the fluctuation of the magnetic field in the axial direction. Further, as shown in FIG. 1, the bias magnet 53 attracts the magnetic body 8 through the glass plate 7 in a state where the tip surface thereof is in contact with the glass plate 7. Therefore, the pencil type speaker 1 can be easily attached (fixed) to the glass plate 7 by sandwiching the glass plate 7 between the bias magnet 53 and the magnetic body 8. The lower casing 2b is formed with a holding portion (not shown) that can hold the columnar magnetostrictive element 51 horizontally. As shown in FIG. The bias magnet 53 can be fixed so that the body 2 is horizontal. The drive coil 54 corresponds to a magnetic field generation unit in the present invention, and is arranged such that its central axis is coaxial with the central axis of the columnar magnetostrictive element 51 as shown in FIGS. Further, as shown in FIG. 2, the drive coil 54 receives a drive current from the acoustic signal amplifying unit 3 via a connection cable, and generates a magnetic field on its axis (on the axis of the columnar magnetostrictive element 51).

  Next, the overall operation of the pencil type speaker 1 will be described.

  As shown in FIG. 1, the magnetic body 8 on the back surface side of the glass plate 7 is attracted to the bias magnet 53 via the glass plate 7 in a state where the tip surface of the bias magnet 53 is in contact with the glass plate 7. Thus, the pencil type speaker 1 is attached to the glass plate 7. In this state, in the pencil type speaker 1, the acoustic signal amplifying unit 3 amplifies an acoustic signal input from the outside via the acoustic signal cable 6 and supplies a driving current to the driving coil 54. At this time, the drive coil 54 applies a magnetic field generated based on the supplied drive current to the columnar magnetostrictive element 51. For this reason, the columnar magnetostrictive element 51 expands and contracts in the axial direction according to the applied magnetic field. At this time, the partition plate 22 functions as a stopper (that is, the weight of the pencil speaker 1 is an inertial mass), so that vibration due to expansion and contraction of the columnar magnetostrictive element 51 is transmitted to the glass plate 7 via the bias magnet 53. The In this state, when the glass plate 7 vibrates, an acoustic signal input from the outside is output from the glass plate 7 as a sufficiently audible sound.

  Thus, according to this pencil type speaker 1, although it is a simple fixing method of adsorbing the magnetic body 8 on the back surface side through the glass plate 7 to the bias magnet 53 of the pencil type speaker 1, The pencil-type speaker 1 can be easily attached to and detached from the vibration transmission target body on which the bias magnet 53 can attract the magnetic body 8 with the vibration transmission target body interposed therebetween.

  The present invention is not limited to the configuration described above. For example, the configuration in which the bias magnet 53 is disposed on the other end side of the columnar magnetostrictive element 51 has been described above. However, as in the pencil type speaker 1A shown in FIG. It is also possible to adopt a configuration that is fixed (arranged) to the other end side of the. In the following description, components having the same functions as those of the pencil type speaker 1 are denoted by the same reference numerals, and redundant description is omitted. In this case, in the pencil type speaker 1A, as shown in the figure, the bias magnet 10 that applies a bias magnetic field to the columnar magnetostrictive element 51 in a state where the tip surface of the magnetic body 55 is in contact with the glass plate 7 is used. By attaching the magnetic body 55 via the glass plate 7, the magnetic body 55 is attached to the glass plate 7. The pencil type speaker 1A is also a simple fixing method in which the magnetic body 55 of the pencil type speaker 1 is attracted to the bias magnet 10 via the glass plate 7, and the bias is sandwiched between arbitrary vibration transmission objects. The pencil type speaker 1 </ b> A can be easily attached to and detached from the vibration transmission target body on which the magnet 10 can attract the magnetic body 55.

  Next, the configuration of the speaker 11 to which the speaker according to the present invention is applied will be described with reference to the drawings. In the following description, components having the same functions as those of the pencil type speaker 1 are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIG. 4, the speaker 11 is formed of a wooden board and has an opening 12 a formed on one side thereof, and a box-shaped housing 12 that houses the pencil-type speaker 1 and a housing 2 for fixing the housing 11. The magnetic body 8 is provided. A diaphragm (a vibration transmission target body in the present invention) 13 formed of, for example, a veneer plywood is detachably fitted in the opening 12a of the casing 12, and the diaphragm 13 and the casing 12 are compatible with each other. It functions as a resonance box. Further, an insertion hole 12 b for drawing out the acoustic signal cable 6 is formed on the back surface of the housing 12 facing the diaphragm 13.

  Next, the overall operation of the speaker 11 will be described.

  First, the pencil type speaker 1 is attached to the housing 12. Specifically, with the diaphragm 13 removed from the housing 12 and the magnetic body 8 pressed against one surface of the diaphragm 13, the bias magnet 53 of the pencil type speaker 1 is pressed against the other surface of the diaphragm 13. . At this time, the magnetic body 8 is attracted with the bias magnet 53 sandwiching the diaphragm 13 together with the magnetic body 8. Therefore, the pencil type speaker 1 is attached (fixed) to the diaphragm 13. Next, after the diaphragm 13 to which the pencil type speaker 1 is attached is fitted into the opening 12a of the housing 12, the acoustic signal cable 6 is pulled out from the insertion hole 12b and connected to an acoustic device (not shown). Thereby, the pencil type speaker 1 is easily attached to the housing 12.

  On the other hand, when outputting sound from the speaker 11, the acoustic signal amplifying unit 3 amplifies an acoustic signal input from the outside via the acoustic signal cable 6 and supplies a driving current to the driving coil 54. At this time, the drive coil 54 applies a magnetic field generated based on the supplied drive current to the columnar magnetostrictive element 51. For this reason, the columnar magnetostrictive element 51 expands and contracts in the axial direction according to the applied magnetic field. At this time, the partition plate 22 functions as a stopper (that is, the weight of the housing 2 is an inertial mass), so that vibration due to expansion and contraction of the columnar magnetostrictive element 51 is transmitted to the diaphragm 13 via the bias magnet 53. . In this state, the sound generated when the diaphragm 13 vibrates is directly output from the diaphragm 13 and the sound resonated by the housing 12 is output. Therefore, a sufficiently audible sound is output from the speaker 11.

  As described above, the bias magnet 53 is attached to the magnetic body 8 with an arbitrary vibration transmission target body (the vibration plate 13) sandwiched between the magnetic bodies 8 by the bias magnet 53 via the diaphragm 13. The pencil type speaker 1 can be easily attached to and detached from the vibration transmission target body capable of adsorbing water. Therefore, since it can be easily replaced with an arbitrary diaphragm 13, various sound qualities can be fully enjoyed and the design change of the speaker 11 can be fully enjoyed.

  Moreover, it can also comprise using the above-mentioned pencil type speaker 1A like the speaker 11A shown in FIG. The speaker 11A includes a box-shaped casing 14 that is formed of a wood board and has an opening 14a formed on one surface thereof and that accommodates the pencil-type speaker 1A. In this case, the housing 14 constitutes a vibration transmission object in the present invention. In the following description, components having the same functions as those of the components in the speaker 11 are denoted by the same reference numerals, and redundant description is omitted.

  Next, the overall operation of the speaker 11A will be described.

  First, the pencil type speaker 1 </ b> A is attached to the housing 14. Specifically, in a state where the bias magnet 10 is pressed against one surface of the housing 14, the magnetic body 55 of the pencil type speaker 1 </ b> A is pressed from the back side of the one surface. At this time, the magnetic body 55 is attracted while the bias magnet 10 sandwiches one surface of the housing 14 together with the magnetic body 55. Therefore, the pencil-type speaker 1A is attached (fixed) to the housing 14. Next, the acoustic signal cable 6 drawn out from the insertion hole 14a is connected to an acoustic device (not shown). Thereby, the pencil type speaker 1 </ b> A is easily attached to the housing 14.

  On the other hand, when the sound is output from the speaker 11 </ b> A, similarly to the speaker 11, the acoustic signal amplifying unit 3 amplifies the acoustic signal input from the outside via the acoustic signal cable 6 and supplies the drive current to the drive coil 54. By supplying, the columnar magnetostrictive element 51 contracts. At this time, vibration due to the expansion and contraction is transmitted to one surface of the housing 14 via the magnetic body 55. In this state, the sound generated by the vibration of the housing 14 is directly output and the sound resonated by the housing 14 is also output. Therefore, a sufficiently audible sound is output from the speaker 11A.

  In this way, the bias magnet 10 is magnetic while sandwiching an arbitrary vibration transmission target body (housing 14) with a simple fixing method in which the magnetic body 55 is attracted to the bias magnet 10 through one surface of the housing 14. The pencil type speaker 1 can be easily attached to and detached from the vibration transmission target body that can adsorb the body 55. Therefore, since it can be easily exchanged for an arbitrary housing 14, various sound qualities can be fully enjoyed and the design change of the speaker 11A can be fully enjoyed.

  The present invention is not limited to the configuration described above. For example, in the pencil type speakers 1 and 1A and the speakers 11 and 11A described above, the example in which the dry battery 41 is disposed inside the housing 2 has been described. However, instead of the dry battery 41, a DC power supply is externally connected via a power cable. It is also possible to employ a configuration in which the commercial AC power supplied via the power cable is converted into a DC power inside the housing 2. Further, although the configuration in which the power switch 32 is disposed in the housing 2 has been described, a configuration in which the power switch 32 is pulled out from the housing 2 with a connection cable may be employed.

  Moreover, although the vibration transmission object in the present invention has been described by taking the speakers 11 and 11A configured by the vibration plate 13 or the housing 14 as an example, the vibration transmission object is not limited to this, but a single flat plate, It can be configured in any shape such as a frame.

  Further, although the pencil type speakers 1 and 1A and the speakers 11 and 11A having a single columnar magnetostrictive element 51 are described above, the number of the columnar magnetostrictive elements 51 is not limited to one, and a plurality of columnar magnetostrictive elements 51 may be provided. it can.

1 is a cross-sectional view showing a configuration of a pencil type speaker 1. FIG. It is a block diagram which shows the electric circuit of the pencil-type speaker 1 (1A). It is sectional drawing which shows the structure of the pencil-type speaker 1A. 2 is a cross-sectional view showing a configuration of a speaker 11. FIG. It is sectional drawing which shows the structure of 11 A of speakers.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1A Pencil type speaker 11, 11A speaker 7 Glass plate 8,55 Magnetic body 10,53 Bias magnet 12,14 Case 13 Diaphragm 22 Partition plate 51 Columnar magnetostrictive element 54 Drive coil

Claims (4)

A columnar magnetostrictive element that is provided with a stopper on one end side, the one end is defined as a fixed end and the other end is defined as a free end and expands and contracts along the axial direction, and the columnar magnetostriction is driven by a drive current based on an acoustic signal. A magnetic field generator for generating a magnetic field for expanding and contracting the element, and a permanent magnet disposed on the other end side of the columnar magnetostrictor to apply a bias magnetic field to the columnar magnetostrictor,
In a state in which the permanent magnet is in contact with the vibration transmission target body, the permanent magnet is configured to be attachable to the vibration transmission target body by adsorbing the magnetic body via the vibration transmission target body and the permanent magnet. An acoustic device configured to be able to transmit vibration due to expansion and contraction of a columnar magnetostrictive element to the vibration transmission target body. A columnar magnetostrictive element that is provided with a stopper on one end side, the one end is defined as a fixed end and the other end is defined as a free end and expands and contracts along the axial direction, and the columnar magnetostriction is driven by a drive current based on an acoustic signal. A magnetic field generator for generating a magnetic field for expanding and contracting the element, and a magnetic body disposed on the other end side of the columnar magnetostrictive element,
In a state in which the magnetic body is in contact with the vibration transmission target body, the vibration transmission is performed by adsorbing the magnetic body to the permanent magnet capable of applying a bias magnetic field to the columnar magnetostrictive element via the vibration transmission target body. An acoustic device configured to be attachable to a target body and configured to be able to transmit vibration due to expansion and contraction of the columnar magnetostrictive element to the vibration transmission target body.   A stopper is provided on one end side, the one end is defined as a fixed end, the other end is defined as a free end, and the columnar magnetostrictive element expands and contracts along the axial direction, and the columnar magnetostriction is driven by a drive current based on an acoustic signal. A magnetic field generator for generating a magnetic field for expanding and contracting the element; a permanent magnet disposed on the other end side of the columnar magnetostrictive element to apply a bias magnetic field to the columnar magnetostrictive element; and one surface of the permanent magnet in contact with the permanent magnet A vibration transmission object disposed in the state, and a magnetic body disposed on the other surface of the vibration transmission object and attracted to the permanent magnet through the vibration transmission object, A speaker configured to be able to transmit vibration caused by expansion and contraction of the columnar magnetostrictive element to the vibration transmission object.   A stopper is provided on one end side, the one end is defined as a fixed end, the other end is defined as a free end, and the columnar magnetostrictive element expands and contracts along the axial direction, and the columnar magnetostriction is driven by a drive current based on an acoustic signal. A magnetic field generator for generating a magnetic field for expanding and contracting the element, a magnetic body disposed on the other end side of the columnar magnetostrictive element, and a vibration transmission target disposed with one surface in contact with the magnetic body And a permanent magnet that is disposed on the other surface of the vibration transmission target body, adsorbs the magnetic body through the vibration transmission target body, and applies a bias magnetic field to the columnar magnetostrictive element. A speaker configured to be able to transmit vibration due to expansion and contraction of the columnar magnetostrictive element to the vibration transmission object.

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