Battery charger capable of notifying a user of a power connection state thereof

1. A battery charger for charging a detachably attached battery pack by supplying an electric power from an external power source, the battery charger comprising:

a notification unit for notifying a user of a charging operation by turning on or flickering a light-emitting member,

wherein the notification unit is configured to notify the user of a power connection state of the battery charger by turning on or flickering the light-emitting member immediately after the battery charger is electrically connected to the external power source without attaching the battery pack thereto, and the notification unit turns off the light-emitting member after a predetermined period of time lapses and keeps the light-emitting member in an off-state until the battery pack is attached to the battery charger.

2. The battery charger of claim 1 , wherein a light brightness used in the turning-on or flickering of the light-emitting member performed immediately after the battery charger is electrically connected to the external power source is darker than a light brightness used in the turning-on or flickering of the light-emitting member performed to notify the user of the charging operation.

3. A battery charger for charging a detachably attached battery pack by supplying an electric power from an external power source, the battery charger comprising:

a notification unit for notifying a user of a charging operation by turning on or flickering a light-emitting member,

wherein the notification unit is configured to notify the user of a power connection state of the battery charger by turning on or flickering the light-emitting member immediately after the battery charger is electrically connected to the external power source without attaching the battery pack thereto, and the notification unit turns off the light-emitting member after a predetermined period of time lapses and keeps the light-emitting member in an off-state until the battery pack is attached to the battery charger,

wherein the notification unit includes a sound output unit outputting a sound to the outside, and

wherein the sound output unit notifies the user of the power connection state of the battery charger by outputting a sound immediately after the battery charger is electrically connected to the external power source.

4. A battery charger for charging a detachably attached battery pack by supplying an electric power from an external power source, the battery charger comprising:

a notification unit for notifying a user of a charging operation by turning on or flickering a light-emitting member,

wherein the notification unit is configured to notify the user of a power connection state of the battery charger by turning on or flickering the light-emitting member immediately after the battery charger is electrically connected to the external power source without attaching the battery pack thereto, and the notification unit turns off the light-emitting member after a predetermined period of time lapses and keeps the light-emitting member in an off-state until the battery pack is attached to the battery charger, and

wherein a light brightness used in the turning-on or flickering of the light-emitting member performed immediately after the battery charger is electrically connected to the external power source is darker than a light brightness used in the turning-on or flickering of the light-emitting member performed to notify the user of the charging operation,

wherein the notification unit includes a sound output unit for outputting a sound to the outside, and

wherein the sound output unit notifies the user of the power connection state of the battery charger by outputting a sound immediately after the battery charger is electrically connected to the external power source.

5. The battery charger of claim 1 , wherein if the battery pack is attached to the battery charger in a fully charged state, the notification unit notifies the user of the fully charged state.

6. The battery charger of claim 2 , wherein if the battery pack is attached to the battery charger in a fully charged state, the notification unit notifies the user of the fully charged state.

7. The battery charger of claim 3 , wherein if the battery pack is attached to the battery charger in a fully charged state, the notification unit notifies the user of the fully charged state.

8. The battery charger of claim 1 , wherein the notification unit notifies the user of the power connection state if it is determined that the battery charger is ready to perform the charging operation once the battery pack is attached thereto.

9. The battery charger of claim 1 , wherein the notification unit notifies the user of the power connection state if it is determined that the battery charger is electrically connected to the external power source and there is no failure in the battery charger.

10. The battery charger of claim 1 , wherein the notification units notifies the user of the power connection state without user's manipulation.

11. The battery charger of claim 1 , wherein if the external power source is electrically connected to the battery charger while the battery pack is attached to the battery charger in a fully charged state, the notification unit notifies the user of the fully charged state without notifying the power connection state.

12. The battery charger of claim 3 , wherein the notification unit notifies the user of the power connection state if it is determined that the battery charger is ready to perform the charging operation once the battery pack is attached thereto.

13. The battery charger of claim 3 , wherein the notification unit notifies the user of the power connection state if it is determined that the battery charger is electrically connected to the external power source and there is no failure in the battery charger.

14. The battery charger of claim 3 , wherein the notification units notifies the user of the power connection state without user's manipulation.

15. The battery charger of claim 3 , wherein if the external power source is electrically connected to the battery charger while the battery pack is attached to the battery charger in a fully charged state, the notification unit notifies the user of the fully charged state without notifying the power connection state.