JP2015177485A - Dynamic headphone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of trouble or damage by preventing an excessive amplitude from being generated in a diaphragm even when strong impact or the like is received by a fall or the like while a dynamic headphone is not mounted, the dynamic headphone being configured to drive the diaphragm by vibration of a voice coil.SOLUTION: A dynamic headphone 1 includes a headphone unit 200 including: a diaphragm 10 to which a voice coil 13 is attached; and a magnetic circuit part 20 forming a magnetic gap G to the voice coil, and the voice coil is provided in the headphone unit so as to be vibrated within the magnetic gap. The dynamic headphone 1 further includes: a short-circuiting switch 3 which is electrically connected to both end sides of the voice coil and short-circuits the voice coil by being turned on; and switch changeover means 2, 35 and 42 for switching ON/OFF of the short-circuiting switch 3 in association with mounting/demounting to/from a listener. When the dynamic headphone is mounted by the listener, the short-circuiting switch is turned off and when the dynamic headphone is demounted by the listener, the short-circuiting switch is turned off.

Description

  The present invention relates to a dynamic headphone in which a diaphragm is driven by vibration of a voice coil, and more particularly to a dynamic headphone capable of preventing the voice coil from jumping out and damage to the diaphragm due to excessive amplitude.

For example, as disclosed in Patent Documents 1 and 2, the basic structure of the dynamic headphones is configured as shown in FIG.
As shown in the figure, the dynamic headphones include a headphone unit 200. The headphone unit 200 is an electroacoustic transducer and includes a diaphragm 10, a magnetic circuit unit 20, and a unit frame 30.
The diaphragm 10 includes a center dome 11 and a sub dome 12. The sub dome 12 is an elastic support part, and is integrally connected around the center dome 11. A voice coil 13 is attached to the back surface of the boundary portion between the center dome 11 and the sub dome 12. In order to protect the diaphragm 10, a net-like protector 40 is provided in front of the diaphragm 10.

  The magnetic circuit unit 20 includes a permanent magnet 21 and a yoke 22. The permanent magnet 21 is formed in a disk shape. The yoke 22 is formed in a cup shape. The permanent magnet 21 is magnetized in the thickness direction and is disposed in the yoke 22. A pole piece 23 is provided on the permanent magnet 21. A magnetic gap G is formed between the pole piece 23 and the yoke 22.

The unit frame 30 is formed in a disc shape. A central portion of the unit frame 30 supports the magnetic circuit unit 20. In the diaphragm 10, the peripheral edge of the sub-dome 12 is hermetically supported with respect to the unit frame 30 so that the voice coil 13 can vibrate back and forth within the magnetic gap G.
An annular baffle plate 35 is provided around the unit frame 30. A headphone housing 41 can be attached to the rear surface side (anti-vibration plate side) of the baffle plate 35. An ear pad 42 is attached around the front side (the diaphragm side) of the baffle plate 35.

Further, the first rear air chamber A <b> 1 is formed on the back side of the unit frame 30 by the headphone housing 41. The first rear air chamber A1 has a predetermined volume. Further, the peripheral edge of the sub dome 12 is hermetically supported with respect to the unit frame 30. Therefore, a second rear air chamber A2 is also formed between the diaphragm 10 and the unit frame 30.
The unit frame 30 is provided with a plurality of openings 31. Each opening 31 is provided with an acoustic resistance material 32. The first rear air chamber A1 and the second rear air chamber A2 communicate with each other through the plurality of openings 31.
In this configuration, the diaphragm 10 is vibrated by energizing the voice coil 13 with a sound signal as a current from a sound reproducing device (not shown). Then, the headphone unit 20 operates as a speaker, and sound is emitted from the headphone unit 20.

JP 2010-178006 A JP 2011-155331 A

By the way, the vibration plate 10 needs to be designed so as not to come into contact with the magnetic circuit unit 20 or to jump out of the magnetic cap G due to the vibration. Therefore, the headphones are designed in consideration of the elasticity of the sub dome 12 and the like.
However, an excessive amplitude may occur in the diaphragm 10 due to a strong impact such as dropping when the headphones are not attached. When a large amplitude is generated in the diaphragm 10 as described above, the diaphragm 10 greatly moves forward from the state shown in FIG. 4A as shown in FIG. 4B. As a result, the voice coil 13 may jump out of the magnetic gap G and the voice coil 13 may not be restored as it is.
In order to prevent the voice coil 13 from jumping out of the magnetic gap G, it has also been proposed to move the protector 40 rearward as shown in FIG. However, when the distance between the protector 40 and the diaphragm 10 is shortened, the diaphragm 10 strongly collides with the back surface of the protector 40 as shown in FIG. As a result, there has been a problem that the diaphragm is deformed or damaged by the collision.

  The present invention has been made paying attention to the above points. In a dynamic headphone in which a diaphragm is driven by vibration of a voice coil, excessive vibration is applied to the diaphragm even if it is subjected to a strong impact or the like due to dropping when not attached. An object of the present invention is to provide a dynamic headphone that does not cause an amplitude and can prevent occurrence of a failure or breakage.

In order to solve the above-described problems, a dynamic headphone according to the present invention has a headphone unit provided with a diaphragm to which a voice coil is attached and a magnetic circuit unit that forms a magnetic gap with respect to the voice coil. In the headphone unit, the voice coil is a dynamic headphone provided so as to be able to vibrate within the magnetic gap, and is a short-circuit switch that is electrically connected to both ends of the voice coil and short-circuits the voice coil by an ON operation. And a switch switching means for switching the on / off operation of the short-circuit switch.
Further, the switch switching means is characterized in that the on / off operation of the short-circuit switch is switched in conjunction with the attachment / detachment of a listener, the short-circuit switch is turned off when the listener is worn, and the short-circuit switch is turned on by removal. .
The switch switching means includes an annular baffle plate that supports the headphone unit, an ear pad that is provided on the baffle plate and is directed to a listener's ear when worn, and one end fixed to the ear pad. And a switch pressing member whose other end moves forward and backward in one direction with respect to the baffle plate in conjunction with the compression restoration of the ear pad, the short-circuit switch is provided on the baffle plate, and the ear pad is compressed. Thus, the other end portion of the switch pressing member is separated from the baffle plate to turn off the short-circuit switch, and the ear pad is restored from the compressed state, whereby the other end portion of the switch pressing member is the baffle plate. It is desirable that the short-circuit switch is pressed and turned on in the vicinity.

According to the dynamic headphones configured as described above, the voice coil is short-circuited and stored in the magnetic gap G when not worn. Therefore, when the voice coil is short-circuited to form a closed circuit, a braking force acts so as to prevent vibration of the voice coil in the magnetic field in the magnetic gap. As a result, the vibration of the diaphragm is suppressed, and even if the headphones receive a strong impact or the like, an excessive amplitude is not generated in the diaphragm. Therefore, it is possible to prevent the occurrence of problems such as the voice coil jumping out of the magnetic gap, the breakage of the diaphragm, and the like.
Furthermore, according to the dynamic headphones provided with the switch switching means for switching the on / off operation of the short-circuit switch in conjunction with the attachment / detachment of the listener, when the listener wears, the ear pad is compressed and the short-circuit switch is turned off. Therefore, the dynamic headphones are in a state in which the diaphragm can be driven by the vibration of the voice coil as a normal operation, and sound can be output.
On the other hand, when the listener removes the dynamic headphones, the ear pad is restored from the compressed state, and the other end of the pressing member is pressed close to the short-circuit switch. As a result, the short-circuit switch is turned on.
Thereby, since the voice coil is short-circuited, the vibration of the diaphragm is suppressed.
With such a simple structure, it is possible to obtain a headphone that is resistant to failure, and thus it is possible to provide reliable voice communication without being broken even in situations where it is susceptible to impact, such as for military use or for working at high places.

  In the dynamic headphones in which the diaphragm is driven by the vibration of the voice coil, even if it is subjected to a strong impact or the like due to a drop or the like when it is not worn, an excessive amplitude is not generated in the diaphragm, and the occurrence of malfunction or damage can be prevented.

FIGS. 1A and 1B are cross-sectional views of dynamic headphones according to the present invention. 2A and 2B are circuit diagrams showing the mechanical configuration of the dynamic headphones shown in FIG. FIG. 3 is a cross-sectional view of a conventional dynamic headphone. 4 (a) and 4 (b) are cross-sectional views for explaining the problems of the conventional dynamic headphones. 5A and 5B are cross-sectional views for explaining another problem of the conventional dynamic headphones.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIGS. 1A and 1B are cross-sectional views of dynamic headphones according to the present invention. The present invention can be applied to dynamic headphones that drive a diaphragm by vibration of a voice coil. Further, the configuration related to the headphone unit can use the same configuration as the configuration shown in FIG. Therefore, in FIGS. 1A and 1B, members that can be shared with the configuration of FIG. 3 are denoted by the same reference numerals, and detailed description thereof is omitted.
In FIGS. 1A and 1B, the headphone housing 41 shown in FIG. 3 is not shown, but is actually provided in the same manner.

  As shown in FIGS. 1A and 1B, the dynamic headphone 1 includes a headphone unit 200 as an electroacoustic transducer. The headphone unit 200 includes a diaphragm 10, a magnetic circuit unit 20, and a unit frame 30 in substantially the same configuration as shown in FIG. 3. The headphone unit 200 is energized with an audio signal as a current from an audio reproduction device (not shown) to the voice coil 13. Then, the diaphragm 10 of the headphone unit 200 vibrates and operates as a speaker. As a result, the headphone unit 200 emits sound.

The dynamic headphone 1 has an annular baffle plate. This baffle material supports the headphone unit 200. An ear pad 42 is provided on one surface side of the baffle plate. The ear pad 42 is a portion addressed to the ear part of the listener when the headphones are worn. The baffle plate 35 is formed with a through hole 35a. A rod-shaped pressing member 2 (switch pressing member) is inserted through the through hole 35a. Flange portions 2a and 2b are formed at both ends of the pressing member 2, respectively. One flange portion 2b serves as a foot and is fixed to the back side of the skin 42a of the ear pad 42.
In the ear pad 42, a packing member 42b made of a sponge material is provided inside the skin 42a. However, the pressing member 2 is not held by the stuffing member 42b. Therefore, as shown in FIG. 1B, when the ear pad 42 is compressed, the other flange portion 2 a side protrudes backward with respect to the baffle plate 35. That is, the flange portion 2 a is configured to advance and retract in one direction with respect to the baffle plate 35 in conjunction with the compression and restoration operation of the ear pad 42.

Further, as shown in the drawing, the baffle plate 35 is provided with a pin-like short-circuit switch 3. The flange portion 2a of the pressing member 2 is brought into contact with the short-circuit switch 3 by the advance / retreat operation and can be pressed.
Specifically, as shown in FIG. 1A, the short-circuit switch 3 is pressed by the flange portion 2a of the pressing member 2 when the ear pad 42 is not compressed. Moreover, as shown in FIG.1 (b), when the ear pad 42 is compressed, it will separate from the flange part 2a of the press member 2, and will be in the state which is not pressed.
In this embodiment, the baffle plate 35, the ear pad 42 and the pressing member 2 constitute a switch switching means.

A schematic circuit diagram is shown in FIGS. The short-circuit switch 3 electrically connects both ends of the voice coil 13. As shown in FIG. 1 (a), when the short-circuit switch 3 is pressed, the voice coil 13 is short-circuited (ON operation) as shown in FIG. 2 (a).
On the other hand, when the short-circuit switch 3 is not pressed as shown in FIG. 1B, the voice coil 13 is normally operated (OFF operation) as shown in FIG. 2B.

According to the dynamic headphone 1 configured as described above, when the listener wears the ear pad 42, the ear pad 42 is compressed and the short-circuit switch 3 is turned off as shown in FIG. As a result, the voice coil 13 can be driven as a normal operation. The diaphragm 10 is vibrated by driving the voice coil 13. And the headphone unit 200 will be in the state which can output an audio | voice.
On the other hand, when the listener removes the dynamic headphones 1, the ear pad 42 is restored from the compressed state as shown in FIG. Then, the flange portion 2 a of the pressing member 2 presses close to the short-circuit switch 3. As a result, the short-circuit switch 3 is turned on.
Thereby, the voice coil 13 is short-circuited to form a closed circuit. When the closed circuit is formed, a braking force acts so as to prevent vibration of the voice coil 13 in a magnetic field. As a result, the vibration of the diaphragm 10 is suppressed. Therefore, even if the headphones are subjected to a strong impact or the like, it is possible to prevent problems such as the voice coil 13 jumping out of the magnetic gap G, damage to the diaphragm 10, and the like.
Accordingly, headphones that are resistant to failure can be realized with such a simple structure. Therefore, reliable voice communication can be provided without breaking even under conditions such as military use and high altitude work that are susceptible to impact.

In the above embodiment, the short-circuit switch 3 is provided on the rear surface side of the baffle plate 35, and the short-circuit switch 3 is turned on when the headphones are removed. However, the dynamic headphones according to the present invention are not limited to the configuration.
For example, the short-circuit switch 3 is provided on the front side of the baffle plate 35. Then, when the headphones are removed, the short-circuit switch 3 may be pulled forward in response to the restoration of the ear pad 42. Also with this configuration, the short-circuit switch 3 can be turned on. Further, the short-circuit switch 3 may be separately provided in a housing (not shown) of the dynamic headphones.

DESCRIPTION OF SYMBOLS 1 Dynamic headphones 2 Press member 2a Flange part 3 Push pin switch 10 Diaphragm 13 Voice coil 20 Magnetic circuit part 42 Ear pad 200 Headphone unit 22 Rear acoustic terminal G Magnetic gap

Claims (3)

A headphone unit provided with a diaphragm to which a voice coil is attached and a magnetic circuit unit for forming a magnetic gap with respect to the voice coil, wherein the voice coil is provided so as to vibrate within the magnetic gap; Dynamic headphones,
A dynamic headphone comprising: a short-circuit switch electrically connected to both ends of the voice coil and short-circuiting the voice coil by an on-operation; and switch switching means for switching on / off operation of the short-circuit switch.   The switch switching means switches on / off operation of the short-circuit switch in conjunction with attachment / detachment of a listener, wherein the short-circuit switch is turned off when the listener is worn, and the short-circuit switch is turned on by removal. 1 is a dynamic microphone; The switch switching means is
An annular baffle plate that supports the headphone unit, an ear pad that is provided on the baffle plate and is addressed to the ear part of the listener when worn, and one end of the ear pad is fixed to the ear pad for compression and restoration. In conjunction with the baffle plate, the other end of the switch has a switch pressing member that advances and retreats in one direction,
The shorting switch is provided on the baffle plate;
When the ear pad is compressed, the other end of the switch pressing member is separated from the baffle plate to turn off the short-circuit switch,
3. The dynamic according to claim 2, wherein the ear pad is restored from a compressed state, whereby the other end of the switch pressing member approaches the baffle plate and presses the short-circuit switch to turn on. headphone.

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