Composite switch and portable device with same

1. A composite switch comprising:

a first switch that is actuable by applying a first load to a first key;

a second switch that is actuable by applying a second load to a second key; and

a stopper to prevent the first key from being pressed down when the second key is pressed down to perform a contact operation in the second switch, and

a plurality of projections, wherein a first projection deforms a first flexible member from among a plurality of first flexible members, wherein the first flexible member is located at a center region of the plurality of the first flexible members and the first projection has a height in a direction of a deformation that is longer than a height of a second projection, wherein the second projection deforms a second flexible member from among the plurality of the first flexible members, and the second flexible member located at a position not in the center region of the plurality of the first flexible members; wherein

a keytop of the second key is disposed on a keytop of the first key;

the second key is disposed on the first key, and

a stroke St 1 of the stopper, a stroke St 2 of the second key, and

a stroke St 3 of the first key satisfy following relations St 2 <St 1 and (St 1 −St 2 )<St 3 .

2. The composite switch according to claim 1 , wherein the first key is:

elastically connected to a housing by a first elastic member, movable in both a parallel and a perpendicular direction relative to a first plane of the housing on which the first key is disposed, and rotatable about an axis extending parallel to the first plane; and

the second key is:

elastically connected to the first key by a second elastic member, and

movable in a direction perpendicular to a pushing surface of the first key.

3. The composite switch according to claim 1 , further comprising:

a plurality of second flexible members, wherein each of the plurality of the second flexible members performs a second contact operation in the second switch by changing its shape upon application of the second load to the second key, and

wherein each of the plurality of the first flexible members performs a first contact operation in the first switch by changing its shape upon application of the first load to the first key.

4. The composite switch according to claim 3 , wherein:

the plurality of first flexible members is disposed on a first board; and

the plurality of second flexible members is disposed on a second board that is parallel to the first board.

5. The composite switch according to claim 3 , wherein

said each of the plurality of the first flexible members is dome-shaped; and

the first flexible member from among the plurality of the first flexible members, which is located at the center region of the plurality of the first flexible members, has a higher dome height than the second flexible member from among the plurality of the first flexible members.

6. The composite switch according to claim 3 , wherein the first key includes an analog pointer and a confirm key; and

the confirm key is actuated by deforming the first flexible member from among the plurality of the first flexible members located at the center region of the plurality of the first flexible members.

7. The composite switch according to claim 3 , wherein the first key includes a direction key; and the direction key is actuated by deforming the first flexible member from among the plurality of the first flexible members that is not located at the center region of the plurality of the first flexible members.

8. The composite switch according to claim 3 , further comprising a third key that is connected to the first key by an elastic member and is located around the first key, wherein

the third key includes a menu key; and

the menu key is actuated by deforming the first flexible member from among the plurality of the first flexible members that is not located at the center region of the plurality of the first flexible members.

9. The composite switch according to claim 3 , wherein at least one of the plurality of the first flexible members and the plurality of the second flexible members is a metal dome.

10. The composite switch according to claim 3 , wherein at least one of the plurality of the first flexible members located at the center region of the plurality of the first flexible members is a metal dome, wherein the metal dome includes a projection located at an apex region of the metal dome.

11. The composite switch according to claim 10 , wherein the metal dome is disposed on a third board, and the third board faces a first board, so that the projection faces toward the first board.

12. The composite switch according to claim 1 , wherein the second load is less than the first load.

13. The composite switch according to claim 1 , wherein the second key includes a ten key.

14. The composite switch according to claim 13 , wherein the ten key is located at a center region of the first key; and

a direction key is arranged around the ten key.

15. The composite switch according to claim 1 , wherein the stopper is disposed on a bottom region of the second key and the stopper touches a first board when the second key is pressed down to perform the contact operation in the second switch.

16. The composite switch according to claim 1 , wherein the stopper is disposed on a first board and the stopper touches the second key when the second key is pressed down to perform the contact operation in the second switch.

17. A composite switch comprising:

a first switch that includes a first key pressed down by a first load;

a second switch that includes a second key pressed down by a second load; and

a stopper to prevent the first key from being pressed down when the second key is pressed down to perform a contact operation in the second switch, and

a plurality of projections, wherein a first projection deforms a first flexible member from among a plurality of first flexible members, wherein the first flexible member located at a center region of the plurality of the first flexible members and the first projection has a height in a direction of a deformation that is longer than a height of a second projection, wherein the second projection deforms a second flexible member from among the plurality of the first flexible members, and the second flexible member located at a position not in the center region of the plurality of the first flexible members; wherein

a keytop of the second key is disposed on a keytop of the first key;

the second key is disposed on the first key, and

a stroke St 1 of the stopper, a stroke St 2 of the second key, and a stroke St 3 of the first key satisfy the following relations St 2 <St 1 and (St 1 −St 2 )<St 3 .