Key drive device

1. An electrical key lock device, comprising:

a second gear configured to rotate by driving power received from a motor;

a first gear configured to transfer the driving power, received through the rotation of the second gear, to an external rotational element;

a third gear configured to mesh with the second gear and installed between the second gear and the first gear and configured to transfer the driving power generated by the motor to the first gear; and

a fourth gear configured to mesh with the first gear and the third gear, and installed between the first gear and the third gear,

wherein the third gear enables switching between closing and opening of a transfer path of the driving power between the second gear and the first gear.

2. The electrical key lock device according to claim 1 ,

wherein the third gear is a planet gear of the second gear and moves between a first position at which the transfer path is closed and a second position at which the transfer path is opened.

3. The electrical key lock device according to claim 2 , further comprising:

a motor controller configured to control rotation of the motor such that the motor rotates, according to an input instruction, to drive the first gear while the transfer path is opened,

wherein the third gear moves from the second position to the first position after the driving of the first gear is completed, and

wherein the motor controller is implemented via at least one processor.

4. The electrical key lock device according to claim 3 , further comprising:

a detector configured to detect a position of the third gear,

wherein the motor controller controls the rotation of the motor such that, after the driving of the first gear is completed, the detector detects that the third gear is positioned at the first position and the rotation of the motor is stopped.

5. The electrical key lock device according to claim 3 , further comprising:

a fifth gear installed between the second gear and the first gear and also configured to transfer the driving power generated by the motor to the first gear, wherein

the fifth gear enables switching between closing and opening of an additional transfer path of the driving power between the second gear and the first gear,

the fifth gear moves between a third position at which the additional transfer path is closed and a fifth position at which the additional transfer path is opened,

the input instruction includes one of an unlocking request or a locking request,

the motor controller decides a rotation direction of the motor according to whether the input instruction includes the unlocking request or the locking request, and

the motor controller controls the rotation of the motor such that either the third gear moves from the first position to the second position or the or the fourth fifth gear moves from the third position to the fifth position, based on whether the input instruction is the unlocking request or the locking request.

6. The electrical key lock device according to claim 2 , wherein

the motor includes a motor output shaft,

the electrical key lock device further comprises:

a torque limiter installed between the second gear and the motor output shaft, and

when torque applied to the torque limiter exceeds a predetermined threshold value, the torque limiter slides around the motor output shaft.

7. The electrical key lock device according to claim 2 ,

wherein a knob for rotating the rotational element manually is installed to be coupled with the first gear.

8. The electrical key lock device according to claim 7 , further comprising:

an attachment removable from the rotational element and coupled to the first gear.

9. The electrical key lock device according to claim 8 ,

wherein the knob and the attachment are coaxially installed.

10. The electrical key lock device according to claim 8 , further comprising:

an output shaft coupled to the first gear,

wherein the attachment includes an Oldham coupling coupled to the output shaft.

11. The electrical key lock device according to claim 7 , further comprising:

a rotation measuring unit configured to measure a rotation amount of the first gear.

12. The electrical key lock device according to claim 11 ,

wherein the fourth gear includes the rotation measuring unit installed therein, and

the rotation measuring unit measures the rotation amount of the first gear based on measurement of rotation of the fourth gear.

13. The electrical key lock device according to claim 11 , further comprising:

an operation detector configured to detect a start of rotation of the first gear; and

a measurement controller configured to cause the rotation measuring unit to start measurement of the rotation amount of the first gear when the operation detector detects the start of the rotation of the first gear.

14. The electrical key lock device according to claim 13 ,

wherein, when the rotation measuring unit is performing the measurement of the rotation amount of the first gear, and the operation detector detects that the first gear is in a stop state for a predetermined period of time or more, the measurement controller causes the rotation measuring unit to end the measurement of the rotation amount of the first gear.

15. The electrical key lock device according to claim 11 , further comprising:

a storage configured to store an operation log related to an operation of the knob; and

a log recorder configured to record a measurement result obtained by the rotation measuring unit in the operation log.

16. The electrical key lock device according to claim 15 , further comprising:

a locked state determination unit configured to determine whether or not the external rotational element is in a locked state based on the measurement result obtained by the rotation measuring unit,

wherein the log recorder further records a determination result obtained by the locked state determination unit in the operation log.

17. The electrical key lock device according to claim 1 ,

wherein, when the transfer path is closed, the third gear is disengaged from driving the first gear, and when the transfer path is opened, the third gear is engaged to drive the first gear.