BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to earphone devices. For example, the present invention may be applied to an earplug type earphone device in which a sound tube is inserted to an external auditory meatus with an earpiece interposed therebetween.

Description of the Related Art

An earphone device typically vibrates a diaphragm disposed in a driver unit accommodated in a housing (a casing of the earphone device) in accordance with audio signals supplied from a portable music player or the like, varies a compression state of air, and thus generates sound corresponding to the audio signals.

For example, according to a lateral in-the-ear earphone device, a housing of the earphone device is supported by a tragus and an antitragus of a user, so that the earphone device fits in an ear of the user (for example, see Japanese Examined Patent Application Publication No. 6-81351).

In the above earphone device, since the shape of a pinna varies from person to person, a gap may be present between the housing and an external auditory meatus when the user wears the earphone device, resulting in leakage of sound through the gap.

In addition, in the above earphone device, since the shapes of the tragus and the antitragus vary from person to person, the user may not support the housing by the tragus and the antitragus, resulting in deterioration in fitting comfortability such as that fitting state is not maintained for a long time.

Meanwhile, according to a vertical in-the-ear earphone device, a diaphragm is arranged to directly oppose the entrance of the external auditory meatus of the user, and hence, the shape around the entrance of the external auditory meatus less influences the sound. Accordingly, such an earphone device may provide stable, high-quality sound to the user (for example, see Japanese Examined Patent Application Publication No. 6-59120).

In the above earphone device, a holder, such as a band or a hanger, is used for holding the earphone device when the user wears the earphone device, resulting in lack of portability. Also, the band is located over the top of the head thereby making the user's hair untidy.

To address the disadvantages with the lateral in-the-ear and the vertical in-the-ear earphone devices, as shown inFIGS. 15A to 15C, there is provided an earplug type earphone device30which includes an earpiece31having a profile corresponding to the external auditory meatus when the user wears the earphone device30, a substantially cylindrical sound guide tube32provided in the earpiece31, a substantially spherical housing33in which the sound guide tube32is mounted, a cord retainer34integrally provided with the housing33, and a cord7connected to a driver unit (not shown) provided in the housing33.

FIG. 15Ais a lateral elevational view showing the earphone device30in the Y-Z plane.FIG. 15Bis a rear elevational view showing the earphone device30in the X-Z plane.FIG. 15Cis a bottom plan view showing the earphone device30in the X-Y plane.

The housing33vibrates a diaphragm disposed in the driver unit in accordance with audio signals supplied through the cord7, and thus generates sound corresponding to the audio signals.

The sound guide tube32protrudes from the center portion of a front surface of the housing33, and when the user wears the earphone device30, the sound guide tube32is inserted to the external auditory meatus with the earpiece31interposed therebetween, so that the sound output via the driver unit of the housing33is guided to the external auditory meatus.

The earpiece31is formed of flexible material so that its shape is freely deformable. Once the earpiece31is inserted to the external auditory meatus, the earpiece31is closely attached to the external auditory meatus, thereby maintaining the fitting state in which the earpiece31is closely attached to the user's ear, and providing gentle fitting.

SUMMARY OF THE INVENTION

In the above earphone device30, as shown inFIG. 16Awhich is a cross section of the user who wears the earphone device30viewed from the top taken along the line XVI-XVI, since the width W2of the housing33is restricted to prevent the housing33from abutting on a tragus22, the size of a diaphragm (not shown) accommodated in the housing33is also restricted. Accordingly, the diaphragm is relatively small.

Due to this, the earphone device30only secures a small amount of air at the front of the diaphragm to be compressed or decompressed to output bass sound, and in addition, the air generally flows to the sides of the diaphragm. Accordingly, a compression state of air may not vary sufficiently, and hence, the bass sound may not be output effectively.

In addition, as shown inFIG. 16Bwhich is a cross section of the user who wears an earphone device35viewed from the top taken along the line XVI-XVI, in a case of the earphone device35that employs a housing36having a width W3slightly larger than the width W2of the housing33, a diaphragm accommodated in the housing36may increase in size by the increment of the width W3of the housing36. However, when the earphone device35fits in the user's ear, the housing36may abuts on the tragus22, and hence, it is difficult to maintain the fitting state, and even to insert the earphone device35to the ear.

With the earplug type earphone device30, the size of the diaphragm tends to be restricted for improving the fitting state, resulting in difficulty of providing sufficiently high-quality sound. Contrary, fitting comfortability may be deteriorated if the diaphragm increases in size.

To address the above-described disadvantages, it is desirable to provide an earphone device which provides comfortable fitting, and high-quality sound.

An earphone device according to an embodiment of the present invention includes a housing having a driver unit, and a sound guide tube mounted on a front surface of the housing to protrude from the front surface, in which the sound guide tube is disposed at a position deviated from a center position of the housing.

With this configuration, when the user wears the earphone device in the ear, the width of the housing may be large as compared with the related art without the housing abutting on the tragus. Owing to this, an aperture of a diaphragm disposed in a driver unit accommodated in the housing may increase in size, and thereby providing high-quality sound with improved fitting comfortability for the user. Therefore, there may be provided the earphone device which provides comfortable fitting, and high-quality sound.

