Electronic device including key button

1. An electronic device comprising:

a housing comprising an outer surface configured to at least partially form an external appearance of the electronic device, a button accommodation recess having a predetermined depth from the outer surface in a first direction oriented to an inner space of the electronic device, and at least one through-hole connected to an inner surface of the housing in the button accommodation recess;

a key button disposed through the button accommodation recess, the key button comprising a key top inserted into the button accommodation recess and at least partially exposed to an outside, and a key base coupled to the key top and comprising a protrusion facing a key flexible printed circuit board (FPCB) disposed in the inner space through the at least one through-hole; and

a waterproof member disposed between the key FPCB and the inner surface of the housing to be in close contact therewith,

wherein the protrusion comprises an engagement portion formed at an end thereof to be larger than the protrusion,

wherein, after the protrusion passes through the at least one through-hole, the engagement portion is engaged with the inner surface around the at least one through-hole,

wherein the waterproof member is configured to seal a periphery of the at least one through-hole, and

wherein the key FPCB is configured to perform a switching operation through pressing of the waterproof member by the protrusion and the engagement portion.

2. The electronic device of claim 1 ,

wherein the engagement portion comprises a first inclined surface,

wherein the at least one through-hole comprises a second inclined surface, and

wherein, after the protrusion passes through the at least one through-hole, the first inclined surface of the engagement portion is engaged with the second inclined surface.

3. The electronic device of claim 2 ,

wherein the first inclined surface has a size that gradually increases toward the first direction, and

wherein the second inclined surface is gradually narrowed toward a second direction opposite to the first direction.

4. The electronic device of claim 1 , wherein the engagement portion has an outer surface having a curved shape.

5. The electronic device of claim 1 , wherein the engagement portion has a hook shape to be engaged after passing through the at least one through-hole.

6. The electronic device of claim 1 , wherein the key button is provided in a manner of injection-molding the key base made of a polymer to the key top made of a metal material.

7. The electronic device of claim 6 , further comprising:

a support projection protruding from the key top,

wherein the support projection extends to a vicinity of an end of the protrusion of the key base.

8. The electronic device of claim 1 , further comprising:

at least one engagement projection protruding from a portion of the key base,

wherein the button accommodation recess comprises at least one engagement recess at a corresponding position at which the at least one engagement projection is engaged in the at least one engagement recess.

9. The electronic device of claim 8 , wherein the at least one engagement projection is disposed at each of positions symmetrically opposite to each other in the key base.

10. The electronic device of claim 1 ,

wherein the key FPCB further comprises a dome key, and

wherein the dome key is disposed at a position facing the protrusion of the key button.

11. The electronic device of claim 10 ,

wherein the waterproof member is configured to seal the periphery of the at least one through-hole and a periphery of the dome key.

12. The electronic device of claim 11 ,

wherein the waterproof member further comprises a first accommodation portion provided through a waterproof projection protruding toward the inner surface, and

wherein the engagement portion protruding from the at least one through-hole is accommodated in the first accommodation portion.

13. The electronic device of claim 12 ,

wherein the waterproof member further comprises a second accommodation portion provided through a waterproof projection protruding toward the key FPCB, and

wherein the dome key is accommodated in the second accommodation portion.

14. The electronic device of claim 11 , wherein the waterproof member is made of at least one of urethane, acryl, or silicone.

15. The electronic device of claim 1 , further comprising:

a display disposed in the inner space to be visible from the outside through at least a portion of a front cover of the electronic device.

16. An electronic device comprising:

a front cover;

a rear cover facing away from the front cover;

a side frame connecting the front cover and the rear cover, the side frame comprising an outer surface configured to at least partially form an external appearance of the electronic device, a button accommodation recess having a predetermined depth from the outer surface in a first direction oriented to an inner space of the electronic device, and at least one through-hole connected to an inner surface of the side frame in the button accommodation recess;

a key button disposed through the button accommodation recess, the key button comprising a key top inserted into the button accommodation recess and at least partially exposed to an outside, and a key base coupled to the key top and comprising a protrusion facing a key flexible printed circuit board (FPCB) disposed in the inner space through the at least one through-hole; and

a waterproof member disposed between the key FPCB and the inner surface of the side frame to be in close contact therewith,

wherein the protrusion comprises an engagement portion having a first inclined surface,

wherein the at least one through-hole comprises a second inclined surface,

wherein, when the protrusion passes through the at least one through-hole, the first inclined surface of the engagement portion is engaged with the second inclined surface,

wherein the waterproof member is configured to seal a periphery of the at least one through-hole, and

wherein the key FPCB is configured to perform a switching operation through which the protrusion and the engagement portion press the waterproof member.

17. The electronic device of claim 16 ,

wherein the first inclined surface has a size that gradually increases toward the first direction, and

wherein the second inclined surface is gradually narrowed toward a second direction opposite to the first direction.

18. The electronic device of claim 16 , further comprising:

at least one engagement projection protruding from at least a portion of the key base,

wherein the button accommodation recess comprises at least one engagement recess at a corresponding position at which the at least one engagement projection is engaged in the at least one engagement recess.

19. An electronic device comprising:

a front cover;

a rear cover facing away from the front cover;

a side frame connecting the front cover and the rear cover, the side frame comprising an outer surface configured to at least partially form an external appearance of the electronic device, a button accommodation recess having a predetermined depth from the outer surface in a first direction oriented to an inner space of the electronic device, and at least one through-hole connected to an inner surface of the side frame in the button accommodation recess;

a key button disposed through the button accommodation recess, the key button comprising a key top inserted into the button accommodation recess and at least partially exposed to an outside, and a key base coupled to the key top and comprising a protrusion facing a key flexible printed circuit board (FPCB) disposed in the inner space through the at least one through-hole, wherein the protrusion comprises an engagement portion formed at an end thereof to be larger than the protrusion, and after the protrusion passes through the at least one through-hole, the engagement portion is engaged with the inner surface around the at least one through-hole; and

a waterproof member disposed between the key FPCB and the inner surface of the side frame to be in close contact therewith, the waterproof member being configured to seal a periphery of the at least one through-hole comprising the engagement portion and a periphery of a dome key.

20. The electronic device of claim 19 ,

wherein the waterproof member further comprises a first accommodation portion provided through a waterproof projection protruding toward the inner surface, and

wherein the engagement portion protruding from the at least one through-hole is accommodated in the first accommodation portion.

21. The electronic device of claim 20 ,

wherein the waterproof member further comprises a second accommodation portion is provided through the waterproof projection protruding toward the key FPCB, and

wherein the dome key is accommodated in the second accommodation portion.

22. The electronic device of claim 21 , wherein the waterproof member is made of at least one of urethane, acryl, or silicone.