Refrigerator

1. A refrigerator comprising:

a cabinet having an opening to access a storage chamber provided within the cabinet;

a drawer including a front panel and a storage bin coupled to a rear of the front panel, the drawer being coupled to the cabinet such that drawer moves between a first position in which the front panel closes the opening of the cabinet and the storage bin is received in the storage chamber, and a second position in which the front panel is spaced away from the opening of the cabinet and at least a portion of the storage bin is positioned outside of the storage chamber;

at least first and second pinions positioned at a lower surface of the storage chamber;

a driving motor to supply a driving force for rotation of the first and second pinions; and

at least two rack gear assemblies positioned at a lower surface of the storage bin, and to operate based on rotations of the first and second pinions so that the drawer moves between the first position and the second position,

wherein the first rack gear assembly includes:

a first rack having a first rack gear to engage with gear teeth of the first pinion; and

an idle gear provided at the first rack to engage with the gear teeth of the first pinion, and the idle gear to allow the first pinion to idle,

wherein lower ends of teeth of the idle gear are lower than a lower end of gear teeth of the first rack gear.

2. The refrigerator of claim 1 , wherein a sensing device is provided at the drawer and the cabinet, and

when the sensing device senses closing of the drawer, the driving motor is to provide a driving force for providing a driving operation by a predetermined time or a predetermined number of rotations from when the closing of the drawer is sensed, and then the driving motor is to deactivate the driving operation.

3. The refrigerator of claim 2 , wherein the sensing device comprises:

a sensor provided at the storage chamber; and

a sensing member to be sensed by the sensor.

4. The refrigerator of claim 3 , wherein the sensor is provided at a bottom in the storage chamber, and the sensing member is provided at a lower surface of the storage bin.

5. The refrigerator of claim 3 , wherein the sensor is a hall sensor, and the sensing member is a magnet.

6. The refrigerator of claim 2 , wherein the driving motor is configured to provide the driving force for performing the driving operation from when the closing of the drawer is sensed by the sensing device, and then the driving motor is to deactivate the driving operation, wherein the driving operation is to be performed for an amount of time or a number of rotations in which the first rack gear is further moved by at least one pitch of gear teeth of the first rack gear.

7. The refrigerator of claim 6 , wherein the driving motor is configured to provide the driving force for performing the driving operation from when the closing of the drawer is sensed by the sensing device, and then the driving motor is to deactivate the driving operation, wherein the driving operation is to be performed so that the first pinion is further rotated by two rotations or less.

8. The refrigerator of claim 1 , wherein the idle gear is provided at the first rack of the first rack gear assembly.

9. The refrigerator of claim 8 , wherein the idle gear is positioned in front of the first rack gear provided at the first rack of the first rack gear assembly.

10. The refrigerator of claim 9 , wherein the idle gear includes one gear tooth to engage with the gear teeth of the first pinion.

11. The refrigerator of claim 10 , wherein the idle gear includes two gear teeth, and a pitch of the two gear teeth of the idle gear is same as a pitch of two of the gear teeth of the first rack gear.

12. The refrigerator of claim 11 , wherein the idle gear is to elastically move up such that the idle gear is released from engagement with the first pinion, and the idle gear to elastically move down such that the idle gear is engaged with the first pinion.

13. The refrigerator of claim 12 , wherein the idle gear is to elastically move back and forth for engagement and release with the first pinion.

14. The refrigerator of claim 13 , wherein the first rack includes a first seating step provided at an upper side of the idle gear, and a first elastic member for up and down movement is provided between the first seating step and the idle gear.

15. The refrigerator of claim 14 , wherein the first elastic member for up and down movement is positioned at a portion of an upper surface of the idle gear, the portion being positioned in the upper side of the idle gear between the two gear teeth of the idle gear.

16. The refrigerator of claim 14 , wherein the first rack includes a second seating step provided in front of the idle gear, and a second elastic member for back and forth movement is provided between the second seating step and the idle gear.

17. The refrigerator of claim 8 , wherein the first rack includes a cover body to cover an exterior of the idle gear.