Earphone device

1. An earphone comprising:

a housing having (i) a front portion having a front surface, (ii) a rear portion including a rear-most surface, and (iii) a cord lead-out portion whereat a cord is led out of the housing, the housing houses a driver unit;

a sound guide tube protruded from the front surface; an earpiece provided around the sound guide tube; and

a first hole formed at a surface of the rear portion of the housing other than the rear-most surface thereof,

the driver unit separates a space of the housing between a front space positioned at a front surface side and a rear space positioned at a rear surface side,

the rear space is connected to an outer space of the housing through the first hole, the cord is led out from the driver unit through the rear space and the cord lead-out portion to outside the earphone, and

the cord lead-out portion is located between the driver unit and the rear-most surface such that the rear-most surface is located beyond the cord lead-out portion in a rearward direction and the cord lead-out portion is configured to enable the cord to be led out to the outside from a side surface of the housing such that the cord is substantially perpendicular to the side surface of the housing at a position outside the earphone whereat the cord exits the earphone,

wherein the longitudinal axis of the cord lead-out portion coincides with an axis that passes through a mid-point of the front surface and a mid-point of the rear surface.

2. The earphone according to claim 1 , wherein the first hole is opened in a direction from the front surface toward the rear-most surface.

3. The earphone according to claim 1 further comprising:

a second hole formed at the rear portion of the housing, wherein the second hole is positioned at an opposite side of the first hole.

4. The earphone according to claim 1 further comprising a second hole having a same shape as the first hole.

5. The earphone according to claim 1 , wherein the first hole is covered by a protecting member having an outer hole.

6. The earphone according to claim 1 further comprising a front hole at the front surface of the housing outside of the sound guide tube.

7. The earphone according to claim 1 , wherein

an angle of the sound guide tube is no less than 10° and no more than 60° with respect to the center line of the driver unit.

8. The earphone according to claim 1 , further comprising a projecting portion configured to project from the other surface of the rear portion and extend in a direction that is away from the driver unit.

9. The earphone according to claim 1 , further comprising:

a projecting portion configured to project from the other surface of the rear portion and extend in a direction that is away from the driver unit, wherein the projecting portion and the housing are separated by a constricted portion.

10. The earphone according to claim 1 , further comprising an annular portion configured to cover a portion of an outer surface of the housing.

11. The earphone according to claim 1 , wherein the earphone is configured to generate sound corresponding to the audio signals supplied from a music player.

12. The earphone according to claim 1 , in which the housing houses a cord knot.

13. The earphone according to claim 1 , in which the driver unit has a disk-like diaphragm.

14. The earphone according to claim 1 , further comprising a metallic circular protection plate between the front surface and the rear-most surface.

15. The earphone according to claim 1 , in which the rear-most surface is located beyond the cord lead-out portion in a rearward direction along a housing center axis, in which the housing center axis passes through a mid-point of the front surface and a mid-point of the rear surface and the rearward direction is toward the rear portion from the front surface.

16. The earphone according to claim 1 , wherein at the position outside the earphone whereat the cord exits the earphone the cord is substantially perpendicular to the longitudinal axis of the cord lead-out portion.