Hinge module and foldable electronic device including the same

1. A foldable electronic device comprising:

a first housing;

a second housing provided in a shape corresponding to a shape of the first housing; and

a hinge module rotatably connecting the first housing to the second housing, the hinge module configured to fix the first housing and the second housing at a certain opening angle,

wherein the hinge module includes:

a fixed gear fixed without rotation and configured to allow a rotation of a counterpart gear in a first direction, and limit a rotation of the counterpart gear in a second direction opposite to the first direction,

a guiding gear configured to allow a rotation of a counterpart gear in the second direction and limit a rotation of the counterpart gear in the first direction,

a first rotary gear configured to be engaged with the fixed gear,

a second rotary gear configured to be engaged with the guiding gear, and

an elastic member arranged between the first rotary gear and the second rotary gear, and providing an elastic force for the first rotary gear and the second rotary gear to move toward the fixed gear and the guiding gear, respectively.

2. The foldable electronic device of claim 1 , wherein the hinge module further includes a shaft gear configured to pass through the fixed gear, the guiding gear, the first rotary gear, the second rotary gear, and the elastic member.

3. The foldable electronic device of claim 2 , wherein the shaft gear includes a first shaft gear serving as a rotation shaft of the first housing and a second shaft gear serving as a rotation shaft of the second housing.

4. The foldable electronic device of claim 2 , wherein the first rotary gear and the second rotary gear are provided to advance and retreat in an axial direction of the shaft gear.

5. The foldable electronic device of claim 4 , wherein when a distance in which the first rotary gear advances and retreats with respect to the second rotary gear is g, and a height of the first rotary gear is h, the distance and the height satisfy a condition

g≥h.

6. The foldable electronic device of claim 4 ,

wherein the first rotary gear includes a first coupling portion extending in a direction parallel to the axial direction of the shaft gear and having a cross section of an arc shape, and

wherein the second rotary gear includes a second coupling portion extending in a direction parallel to the axial direction of the shaft gear, and configured to form a circular cross section together with the first coupling portion by being coupled to the first coupling portion in the axial direction.

7. The foldable electronic device of claim 6 ,

wherein the first coupling portion includes guide protrusions formed to protrude outward from both sides of the first coupling portion, and

wherein the second coupling portion includes guide grooves formed to be recessed inward from both sides of the second coupling portion.

8. The foldable electronic device of claim 7 , wherein the guide protrusion has a cross-sectional shape that corresponds to a cross-sectional shape of the guide groove.

9. The foldable electronic device of claim 1 , wherein the hinge module includes:

a rotating member provided to rotate together with the first housing or the second housing;

a wing member provided to rotate together with the rotating member, and including the guiding gear; and

a transmission shaft configured pass through each of the rotating member and the wing member to transmit a rotational force of the rotating member to the wing member.

10. The foldable electronic device of claim 9 ,

wherein the rotating member includes a transmission shaft hole formed to allow the transmission shaft to be inserted thereinto, and

wherein the transmission shaft hole configured to limit a movement range of the transmission shaft such that a folding range of the first housing or the second housing is limited.

11. The foldable electronic device of claim 3 , wherein the hinge module further includes a link gear arranged between the first shaft gear and the second shaft gear to transmit the rotation of the first shaft gear to the second shaft gear or transmit the rotation of the second shaft gear to the first shaft gear.

12. The foldable electronic device of claim 2 ,

wherein, when the shaft gear rotates in the first direction, the first rotary gear rotates relative to the fixed gear in the first direction, and

wherein, when the second rotary gear and the guiding gear rotate together with the first rotary gear in the first direction.

13. The foldable electronic device of claim 12 ,

wherein, when the shaft gear rotates in the second direction, the fixed gear, the first rotary gear and the second rotary gear are fixed, and

wherein, when the guiding gear rotates relative to the second rotary gear in the second direction.

14. The foldable electronic device of claim 12 ,

wherein, when the first rotary gear rotates relative to the fixed gear in the first direction, and

wherein, when the first rotary gear moves toward the second rotary gear.

15. The foldable electronic device of claim 13 ,

wherein, when the guiding gear rotates relative to the second rotary gear in the second direction, and

wherein, when the second rotary gear moves toward the first rotary gear.

16. A hinge module rotatably connecting a first housing to a second housing, the hinge module comprising:

a fixed gear fixed without rotation and configured to allow a rotation of a counterpart gear in a first direction, and limit a rotation of the counterpart gear in a second direction opposite to the first direction;

a guiding gear configured to allow a rotation of a counterpart gear in the second direction and limit a rotation of the counterpart gear in the first direction;

a first rotary gear configured to be engaged with the fixed gear;

a second rotary gear configured to be engaged with the guiding gear; and

an elastic member arranged between the first rotary gear and the second rotary gear, and providing an elastic force for the first rotary gear and the second rotary gear to move toward the fixed gear and the guiding gear, respectively.

17. The hinge module of claim 16 ,

wherein, when a shaft gear rotates in the first direction, the first rotary gear rotates relative to the fixed gear in the first direction, and

wherein, when the second rotary gear and the guiding gear rotate together with the first rotary gear in the first direction.

18. The hinge module of claim 17 ,

wherein, when the shaft gear rotates in the second direction, the fixed gear, the first rotary gear and the second rotary gear are fixed, and

wherein, when the guiding gear rotates relative to the second rotary gear in the second direction.

19. The hinge module of claim 17 ,

wherein, when the first rotary gear rotates relative to the fixed gear in the first direction, the first rotary gear moves toward the second rotary gear, and

wherein, when the guiding gear rotates relative to the second rotary gear in the second direction, the second rotary gear moves toward the first rotary gear.

20. A foldable electronic device comprising:

a first housing;

a second housing provided in a shape corresponding to a shape of the first housing; and

a hinge module rotatably connecting the first housing to the second housing, the hinge module configured to fix the first housing and the second housing at a certain opening angle,

wherein the hinge module includes:

a first fixed gear fixed without rotation and configured to allow a rotation of a counterpart gear in a first direction, and limit a rotation of the counterpart gear in a second direction opposite to the first direction,

a second fixed gear fixed together with the first fixed gear and configured to limit a rotation of a counterpart gear in the first direction, and allow a rotation of the counterpart gear in the second direction,

a first guiding gear provided to rotate together with the first housing and configured to allow a rotation of a counterpart gear in the second direction and limit a rotation of the counterpart gear in the first direction,

a second guiding gear provided to rotate together with the second housing and configured to limit a rotation of a counterpart gear in the first direction and limit a rotation of the counterpart gear in the second direction,

a first rotary gear unit including a first gear engaged with the first fixed gear, a second gear engaged with the first guiding gear, and a first elastic member arranged between the first gear and the second gear, and

a second rotary gear unit including a third gear engaged with the second fixed gear, a third gear engaged with the second guiding gear, and a second elastic member arranged between the third gear and a fourth gear.