JPWO2008004274A1 - Audio transmission device - Google Patents

Abstract

The headphone 50 includes a vibration unit 10 that converts an electrical signal for generating sound into vibration, a main body 20 that holds the vibration unit 10, an arm 30 that attaches the main body 20 to a user's head, and an arm 30. And a joint portion 40 that pivotally supports the main body 20 in a rotatable manner. The joint unit 40 includes an urging mechanism that urges the main body 20 in a direction in which the vibration unit 10 is pressed against the user's head when the main body 20 is mounted on the user's head. The vibration unit 10 is pressed near the user's ear not only by the elastic force of the arm 30 but also by the biasing mechanism of the joint unit 40.

Description

  The present invention relates to an audio transmission device for transmitting audio to a user.

  Certain magnetic materials are distorted in response to changes in the external magnetic field. Further, when such a magnetic material is deformed by applying stress, the magnetic characteristics change according to the stress. These phenomena are called “magnetostriction”. In recent years, materials having a displacement of 50 to 100 times the displacement amount of a conventionally known magnetostrictive element have been discovered, and they are called “super magnetostrictive elements”.

When an alternating magnetic field is applied to the magnetostrictive element, vibration having a frequency equal to the frequency of the alternating magnetic field can be generated. Using such a phenomenon, for example, it is expected that a giant magnetostrictive element is applied to a bone conduction headphone, a hearing aid, or the like (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 2001-258095

  In an audio transmission device such as headphones, it is important to efficiently transmit vibration to a user's eardrum, skull, or the like. In particular, in a bone-conduction type headphone, unless the vibrating portion is in close contact with the user's body, the vibration is not transmitted well to the user's bone and the sound quality is deteriorated.

  This invention is made | formed in view of such a condition, The objective is to provide the technique which improves the usability | use_condition or transmission efficiency of an audio | voice transmission apparatus.

  One embodiment of the present invention relates to an audio transmission device. The audio transmission device includes a main body including a vibration unit that converts an electrical signal for generating sound into vibration, a mounting unit for mounting the main body on a user's head, the mounting unit, and the main body. A joint that supports the shaft, and when the body is mounted on the user's head, the joint urges the body in a direction in which the vibration unit is pressed against the user's head. Including a biasing mechanism.

  Since the main body is pivotally supported with respect to the mounting portion, the contact angle between the vibration portion and the user's head can be appropriately adjusted. In addition, since the vibration unit is pressed against the user's head by the urging mechanism, the adhesion can be improved, and an appropriate contact state can be maintained for a long time. Thereby, the transmission efficiency of vibration can be improved and sound quality can be improved. Moreover, a user's wearing feeling can be improved.

  The mounting portion may be an arm biased so as to sandwich the user's head. The arm may have a structure that holds the top of the head, a structure that holds the back of the head, or a structure that holds the face part like glasses. The arm may include an ear hook for hanging the arm on the user's ear.

  The surface of the vibrating portion that contacts the user's head may be a convex surface having a high center. Thereby, the adhesiveness of a vibration part and a user's head can be improved more. A cover may be attached or a film may be provided on the surface of the vibration unit that contacts the user's head. The cover or coating may have elasticity. Thereby, a user's wearing feeling can be improved more. The surface of the cover or coating may be a convex surface having a high center vicinity.

  The vibration unit may include a giant magnetostrictive element.

  It should be noted that any combination of the above-described constituent elements and a representation of the present invention converted between a method, an apparatus, a system, etc. are also effective as an aspect of the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which improves the usability | use_condition or transmission efficiency of an audio | voice transmission apparatus can be provided.

It is a figure which shows the structural example of the headphones which concern on embodiment. It is a figure which shows another structural example of the headphones which concern on embodiment. It is a figure which shows another structural example of the headphones which concern on embodiment. It is a figure which shows the structural example of a vibration part.

Explanation of symbols

  1 Giant Magnetostrictive Element, 2 Bias Magnet, 3 Bobbin, 4 Coil, 5 Lead Wiring, 6 Vibrating Rod, 8 Housing, 9 Elastic Member, 10 Vibrating Part, 20 Main Body, 21 Screw Part, 22 Protrusion, 29 Circuit, 30 Arm 32 pinching part, 34 ear hook part, 40 joint part, 50 headphones, 81 screw part.

  In the bone conduction type headphones, a vibration generating device that generates vibration according to an audio signal is brought into contact with the vicinity of the user's ear, and the vibration is transmitted to the user's skull or the like so that the user perceives it as sound. At this time, the transmission efficiency and the feeling of wearing are greatly influenced by the contact state between the vibration transmission surface and the user's head. Since the shape of the head varies from person to person, there is a case where the vibration transmission surface cannot be brought into good contact with the head in the same structure as that of a conventional headphone. If a good contact state cannot be maintained, there is a risk that the vibration will not be transmitted well to the user's skull or the like and the sound quality will deteriorate, or the user will feel uncomfortable wearing. In addition, when applying bone conduction type audio transmission devices to hearing aids, etc., elderly people and people with disabilities who use hearing aids wear headphones for a long time. It is necessary to prepare a device having a small shape. Furthermore, in usage scenes where staff members are dealing with customers in restaurants and entertainment facilities and receiving in-store office contact through headphones, it is possible to efficiently transmit voice while being unobtrusive to customers. It is necessary to prepare a possible device. In order to meet such a demand, the present inventor proposes a technique for improving the transmission efficiency of a sound transmission device such as a headphone, particularly a bone-conduction headphone, and the user's wearing feeling in the present embodiment.

  FIG. 1 shows a configuration example of a headphone that is an example of a sound transmission device according to an embodiment. The headphone 50 is an example of a vibration unit 10 that converts an electrical signal for generating sound into vibration, a main body 20 that holds the vibration unit 10, and a mounting unit for mounting the main body 20 on a user's head. An arm 30 and a joint portion 40 that pivotally supports the arm 30 and the main body 20 are provided. The arm 30 has elasticity and is urged so as to sandwich the top of the user's head. The joint unit 40 includes a coil spring that is an example of a biasing mechanism that biases the main body 20 in a direction in which the vibration unit 10 is pressed against a site near the ear of the user's head. The main body 20 and the vibration part 10 are urged in the direction of the arrow in the figure by the coil spring of the joint part 40.

  When the user wears the headphones 50 on the head, the vibration unit 10 comes into contact with the vicinity of the user's ear. The main body 20 has a circuit that inputs an electrical signal to the vibration unit 10. When the electrical signal is input from the circuit to the vibration unit 10, the vibration unit 10 generates vibration according to the electrical signal. The user perceives the vibration transmitted from the vibration unit 10 as a sound by bone conduction through the skull or the like.

  In a general headphone, the joint portion 40 is not provided, and the arm 30 and the main body 20 are directly connected. When the headphone is worn, the arm 30 is widened and put on the head, and the arm 30 is configured to press the vibrating portion 10 of the main body 20 near the user's ear by using a force for returning the arm 30 to its original shape. . However, as described above, such a structure cannot maintain a good contact state, and there is a possibility that the transmission efficiency and the user's wearing feeling are lowered.

  In order to solve such a problem, the headphone 50 of the present embodiment is provided with a joint portion 40 so that the main body 20 can be rotated in a direction substantially perpendicular to the contact portion of the user's head. A coil spring is built in the joint portion 40 so that the vibrating portion 10 is pressed against the contact portion of the user's head. As a result, not only the elastic force of the arm 30 but also the biasing force of the coil spring appropriately presses the vibrating portion 10 against the contact portion of the head, so that the vibrating portion 10 can be brought into close contact with the contact portion. . Thereby, a favorable contact state can be maintained and the transmission efficiency of vibration can be improved. Further, since the main body 20 is rotatable about the joint portion 40, the contact angle between the contact surface of the vibration unit 10 and the surface of the contact portion of the user's body can be adjusted, and the user's wearing feeling can be adjusted. Can be improved. Through experiments conducted by the present inventors, the same headphone 50, that is, the headphone 50 having the same length from the joint portion 40 to the vibration portion 10 is worn in a good contact state regardless of whether it is an adult or a child. I know I can.

  The joint part 40 may be configured by a hinge, a hinge, a hinge, or the like. The biasing mechanism may be configured by a spring mechanism such as a leaf spring, a disc spring, a coil spring, or a torsion spring, or an elastic body such as rubber.

  The surface of the vibration unit 10 that contacts the user's body may be curved according to the shape of the contact portion of the user's body. For example, the surface of the vibration unit 10 may be a convex surface that is high near the center and low near the periphery. Thereby, when the vibration part 10 is pressed near the user's ear, the surface of the vibration part 10 is easily adhered to the skin. Thereby, since the area of the contact surface of the surface of the vibration part 10 and a user's body becomes large, the vibration of the vibration part 10 can be transmitted efficiently and sound quality can be improved. In addition, the user's feeling of use can be improved, and discomfort can be reduced even when the headphones 50 are worn for a long time.

  A cover may be affixed to the surface of the vibration unit 10 that contacts the user's body. In addition, a film may be provided on the surface of the vibration unit 10. The cover or the coating is preferably made of a material having elasticity. Thus, by providing a cover or a coating having elasticity, when the vibration unit 10 is brought into contact with the user's skin, the cover or the coating is deformed according to the shape of the part of the user's body to be contacted. . Thereby, since the area of the contact surface of a cover or a film and a user's body becomes large, the vibration of the vibration part 10 can be transmitted efficiently and sound quality can be improved. Moreover, a user's feeling of use can be improved.

  The cover or coating may be made of an elastic material such as rubber or resin, or a bag made of a deformable soft material such as rubber or resin filled with gas, liquid, gel, or the like. May be. The cover may be attached to the surface of the vibration unit 10 with an adhesive or the like. The film may be formed by coating the surface of the vibration part 10 with a resin or the like. The cover or the coating preferably has an elasticity and a thickness that do not hinder the transmission of sound from the surface of the vibration unit 10 to the outside, for example, the user's skin. Note that, by using a giant magnetostrictive element having a large generated stress as the vibration converting element, even if an elastic cover or coating is provided, sound can be transmitted efficiently.

  The cover may be affixed with an adhesive having an adhesive strength that can be easily peeled off, sticky silicone rubber, or the like. Moreover, you may form a cover or a film with adhesive silicone rubber. For example, when an unspecified user uses the headphones 50, such as installing headphones for viewing at a music CD store or the like, the cover may be exchangeable each time the headphones are used. In addition, even a user who has circumstances such as metal allergy cannot directly contact the skin, by providing a cover or coating made of silicon rubber or resin on the surface of the vibration part 10, The headphones 50 can be used.

  The vibration unit 10 may be pivotally supported with respect to the main body 20 by a universal joint or the like. Thereby, the angle of the vibration part 10 can be finely adjusted so that a better contact with the contact surface of the user's body can be obtained.

  FIG. 2 shows another configuration example of the headphones according to the embodiment. The headphone 50 shown in FIG. 2 is different from the headphone 50 shown in FIG. The arm 30 of the headphone 50 shown in FIG. 2 includes a curved ear hook 34 for hanging on the user's ear and a holding portion 32 biased so as to hold the user's back head. Wear 20 Also in the headphone 50 of this figure, the main body 20 is pivotally supported by the joint portion 40 with respect to the arm 30 so as to be rotatable, similarly to the headphone 50 shown in FIG. The vibrating unit 10 is biased so as to be pressed near the user's ear. Thereby, the transmission efficiency of a vibration and a user's usability can be improved.

  FIG. 3 shows another configuration example of the headphones according to the embodiment. The headphone 50 shown in FIG. 3 is different from the headphone 50 shown in FIG. The arm 30 of the headphone 50 shown in FIG. 3 has a shape similar to that of eyeglasses, and is sandwiched so as to sandwich an ear hook 34 for hanging on the user's ear and a user's face. The main body 20 is attached to the user's head by the unit 32. Also in the headphone 50 of this figure, the main body 20 is pivotally supported by the joint portion 40 with respect to the arm 30 so as to be rotatable, similarly to the headphone 50 shown in FIG. The vibrating unit 10 is biased so as to be pressed near the user's ear. Thereby, the transmission efficiency of a vibration and a user's usability can be improved.

  The arm 30 of the headphone 50 may have a shape such as a hat or a hair band, or only the ear hook. In addition to the arm 30, the mounting portion may be a clip for attaching the main body 20 to a hat, a helmet, or the like. In addition, two vibrating portions 10 may be provided in order to make contact in the vicinity of both ears, or one may be provided in order to make contact in the vicinity of either ear.

  In addition to the vibration unit 10 that transmits sound by bone conduction, a speaker that transmits sound to the eardrum of the ear via air vibration may be provided in the same manner as a conventional headphone. In this case, by providing a speaker of a type that covers the ear, it is possible to block ambient noise and give a deeper immersive feeling. The same sound may be given to the speaker and the vibration unit 10, or different sounds may be given.

  FIG. 4 shows a configuration example of the vibration unit 10. The vibration unit 10 of the present embodiment mainly includes a giant magnetostrictive element 1, a bias magnet 2 (a bias upper magnet 2a and a bias lower magnet 2b), a bobbin 3, a coil 4, lead wires 5a and 5b, and a vibration rod. 6, a housing 8, and an elastic member (string winding ridge) 9.

  The giant magnetostrictive element 1 is used as a vibration converting element for converting a signal obtained by converting sound into vibration, and has a substantially cylindrical outer shape. The upper magnet 2a for biasing on the upper surface and the biasing magnet on the bottom surface. The lower magnets 2b are respectively arranged. The giant magnetostrictive element 1 is housed inside the housing 8 while being sandwiched between the upper biasing magnet 2a and the lower biasing magnet 2b, and the magnetic field generated by the upper biasing magnet 2a and the lower biasing magnet 2b. Is constantly received as a bias magnetic field (the bias magnetic field constantly penetrates the giant magnetostrictive element 1). At the same time, in the giant magnetostrictive element 1, when the housing 8 is connected to the main body 20 by the screw portion 81, the bottom surface is supported by the protrusions 22 of the main body 20, and the vibration rod 6 is elastic on the upper surface of the elastic member 9. It is set so that so-called pre-stress is constantly applied by being pressed by receiving force. The giant magnetostrictive element 1 responds to an input electric signal by receiving a variable magnetic field by a coil 4 disposed in the periphery in a state where a bias magnetic field and prestress are constantly applied as described above. Generated vibration.

  The coil 4 is formed by winding a conductor wire around a central barrel of a bobbin 3 made of a material such as glass base polycarbonate, for example. When an electric signal is input to the conductor wire via the lead wiring, the coil 4 generates a magnetic field correspondingly. When the variable magnetic field generated from the coil 4 penetrates the giant magnetostrictive element 1, the giant magnetostrictive element 1 expands and contracts in accordance with the strength of the variable magnetic field, and is output as vibration.

  One end of the vibrating rod 6 is mechanically connected to the giant magnetostrictive element 1 via the bias upper magnet 2a, and transmits vibration output from the giant magnetostrictive element 1 from the other end to the outside. The vibration rod 6 is provided with a flange portion 61. The flange portion 61 receives a biasing force from the elastic member 9 and is pressed against the upper bias magnet 2a. The pressing force is applied to the giant magnetostrictive element 1 through the bias upper magnet 2a. Further, the flange portion 61 and the elastic member 9 prevent the entire vibration rod 6 from falling out of the housing 8.

  The housing 8 accommodates the giant magnetostrictive element 1, the upper biasing magnet 2a, the lower biasing magnet 2b, the bobbin 3, the coil 4, the vibrating rod 6, and the elastic member 9 in a predetermined state. It is a so-called container (or body). The housing 8 is preferably made of a magnetic material so as not to leak the internal magnetic field to the outside and to generate the internal magnetic field more effectively.

  The housing 8 has a screw portion 81 for connecting with the main body 20. The vibration part 10 is attached to the main body 20 by screwing the screw part 81 of the housing 8 and the screw part 21 of the main body 20 together. The vibration part 10 and the main body 20 may be connected by other screw mechanisms, welding, caulking, resin curing, or the like. The surface of the housing 8 on the main body 20 side is open, and when the vibration unit 10 is attached to the main body 20, the bias lower magnet 2 b directly contacts the main body 20. At this time, the protrusion 22 is provided at a position of the main body 20 where the lower biasing magnet 2b abuts. By tightening the screw, the giant magnetostrictive element 1 is pressed from the protrusion 22 via the lower biasing magnet 2b. A predetermined prestress is applied to the giant magnetostrictive element 1. Thereby, the conversion efficiency between an electric signal and vibration can be improved. In addition, the lead wires 5 a and 5 b are connected to the circuit 29 of the main body 20, and an electric signal input from the circuit 29 is transmitted to the coil 4.

  The end of the giant magnetostrictive element 1 opposite to the output end that transmits vibration to the user (hereinafter referred to as “fixed end”) is supported and fixed by the main body 20. Thereby, since vibration on the fixed end side of the giant magnetostrictive element 1 can be suppressed, vibration of the giant magnetostrictive element 1 can be efficiently transmitted from the output end to the outside. Therefore, good acoustic characteristics can be realized in a wide range of frequencies. In addition, since the function of supporting the fixed end and the function of applying prestress to the giant magnetostrictive element 1 are assigned to the main body 20 including a circuit for inputting an electric signal, not the vibration unit 10, a large Since there is no need to provide a member having an inertial mass in the vibration part 10 and one of the members holding the giant magnetostrictive element 1 can be omitted, the vibration part 10 can be reduced in size and weight. The entire headphone 50 can be reduced in size and weight. It is desirable that the protrusion 22 has sufficient hardness to suppress vibration on the fixed end side of the giant magnetostrictive element 1.

  The present invention has been described based on the embodiments. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. is there.

  The present invention can be used in a voice transmission device that transmits voice to a user.

Claims (8)

A main body including a vibration part that converts an electrical signal for generating sound into vibration;
A mounting portion for mounting the main body on a user's head;
A joint portion that pivotally supports the mounting portion and the main body,
The joint includes an urging mechanism that urges the main body in a direction in which the vibration unit is pressed against the user's head when the main body is mounted on the user's head. Transmission device. The audio transmitting apparatus according to claim 1, wherein the mounting unit is an arm biased so as to sandwich the head of the user. The audio transmission device according to claim 2, wherein the arm has an ear hooking portion for hooking the arm on an ear of the user. The sound transmission device according to any one of claims 1 to 3, wherein a surface of the vibration unit that abuts on the user's head is a convex surface having a high center. The sound transmission device according to any one of claims 1 to 4, wherein a cover is affixed or a coating is provided on a surface of the vibration unit that contacts the user's head. The sound transmission device according to claim 5, wherein the cover or the coating has elasticity. The voice transmission device according to claim 5 or 6, wherein the surface of the cover or the coating is a convex surface having a high center. The sound transmitting device according to claim 1, wherein the vibration unit includes a giant magnetostrictive element.

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