Rollable electronic device including rack gear
An electronic device is provided. The electronic device includes a housing including a first housing and a second housing configured to contain at least a part of the first housing and to move relative to the first housing, a display configured to unfold based on sliding of the first housing, a motor structure disposed in the housing and configured to generate driving power for sliding of the first housing, a pinion gear configured to rotate based on the driving power generated by the motor structure, and a rack gear disposed in the housing and configured to mesh with the pinion gear. The rack gear includes a first part made of a first material, the first part including at least one recess, and a second part including a lower area disposed below the first part, at least a part of the second part being contained in the at least one recess.
1. An electronic device comprising:
a housing comprising a first housing and a second housing configured to accommodate at least a part of the first housing and to move relative to the first housing;
a display configured to unfold based on sliding of the first housing;
a motor structure disposed in the housing and configured to generate driving power for sliding of the first housing;
a pinion gear configured to rotate based on the driving power generated by the motor structure; and
a rack gear disposed in the housing and configured to mesh with the pinion gear,
wherein the rack gear comprises:
a first part made of a first material having a first thermal conductivity, the first part comprising at least one recess and first gear teeth configured to at least partially mesh with the pinion gear, and
a second part comprising a lower area disposed below the first part, at least a part of the second part being accommodated in the at least one recess, the second part being made of a second material having a second thermal conductivity higher than the first thermal conductivity.
2. The electronic device of claim 1 , wherein the second part comprises second gear teeth extending in the lower area, the second gear teeth being at least partially positioned in the at least one recess and configured to contact the pinion gear.
3. The electronic device of claim 1 , wherein the first part comprises a first surface facing the pinion gear, a second surface opposite to the first surface, and a third surface extending from the first surface to the second surface, the third surface defining the at least one recess, and
wherein the second part comprises a fourth surface facing the pinion gear, a fifth surface facing the second surface, and a sixth surface extending from the fourth surface to the fifth surface, the sixth surface facing the third surface.
4. The electronic device of claim 3 , further comprising a lubricating material applied onto the second part and configured to contact the pinion gear.
5. The electronic device of claim 1 ,
wherein the second part comprises second gear teeth configured to at least partially mesh with the pinion gear, and
wherein the first gear teeth are at least partially positioned closer to the pinion gear than the second gear teeth.
6. The electronic device of claim 5 , wherein the first gear teeth are arranged to surround at least a part of the at least one recess.
7. The electronic device of claim 1 ,
wherein the first material comprises at least one of stainless steel or aluminum, and
wherein the second material comprises copper.
8. The electronic device of claim 1 ,
wherein first stiffness of the first material is higher than second stiffness of the second material, and
wherein first strength of the first material is higher than second strength of the second material.
9. The electronic device of claim 1 ,
wherein the motor structure is connected to the first housing, and
wherein the rack gear is connected to the second housing.
10. The electronic device of claim 1 , further comprising a heat dissipation member attached to the second part, the heat dissipation member comprising graphite.
11. The electronic device of claim 1 ,
wherein the motor structure comprises a shaft structure connected to the pinion gear, and
wherein the shaft structure comprises copper.
12. The electronic device of claim 1 , further comprising:
a gear bracket connected to the motor structure and configured to surround at least a part of the pinion gear; and
a heat transfer member connected to the gear bracket and the rack gear.
13. The electronic device of claim 1 , further comprising a battery configured to supply power to the motor structure,
wherein the housing comprises at least one slit positioned between the motor structure and the battery.
14. The electronic device of claim 1 ,
wherein the display comprises a first display area connected to the second housing and a second display area connected to the first housing, and
wherein the electronic device further comprises a display support member configured to support the second display area.
15. An electronic device comprising:
a housing comprising a first housing and a second housing configured to accommodate at least a part of the first housing and to move relative to the first housing;
a display configured to unfold based on sliding of the first housing;
a motor structure disposed in the housing and configured to generate driving power for sliding of the first housing;
a pinion gear configured to rotate based on the driving power generated by the motor structure; and
a rack gear disposed in the housing and configured to mesh with the pinion gear,
wherein the rack gear comprises:
a first part made of a first material having first thermal conductivity, the first part comprising a through-hole and first gear teeth arranged on a periphery of the through-hole, and
a second part made of a second material having second thermal conductivity higher than the first thermal conductivity, the second part comprising a lower area disposed below the first part and second gear teeth extending in the lower area, the second gear teeth being at least partially accommodated in the through-hole.
16. The electronic device of claim 15 , further comprising a lubricating material applied onto the second part and configured to contact the pinion gear.
17. The electronic device of claim 15 , wherein the first gear teeth are at least partially positioned closer to the pinion gear than the second gear teeth.
18. The electronic device of claim 15 ,
wherein the first material comprises at least one of stainless steel or aluminum, and
wherein the second material comprises copper.
19. The electronic device of claim 15 , further comprising a heat dissipation member attached to the second part, the heat dissipation member comprising graphite.
20. The electronic device of claim 1 ,
wherein the first part comprises at least one first fastening hole and the second part comprises at least one second fastening hole positioned to align with the at least one first fastening hole, and
wherein the first part is connected to the second part via the at least one first fastening hole and the at least one second fastening hole.