ELECTRONIC DEVICE

• US 20170006692A1
• Filed: 09/15/2016
• Published: 01/05/2017
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: USUI, Takashi, KATO, Mitsuaki
• Granted Patent: US 10,091,861 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: H05B 45/56 involving measures to prevent abnormal temperature of the LEDs
• CPC Class Codes: H05B 47/105 in response to determined parameters
• CPC Class Codes: H05B 47/17 Operational modes, e.g. switching from manual to automatic mode or prohibiting specific operations

Abstract

According to one embodiment, an electronic device capable of switching power on and power off by a switch outside the electronic device, the electronic device includes a determination unit, a detection unit, an output unit, and a control unit. The determination unit determines whether power is supplied from an AC power source or not. The detection unit detects a conductive state of the switch. The control unit performs at least one of cutting off power to be supplied to the output unit, supplying power from the AC power source to the output unit, and supplying power from a second power source different from the AC power source to the output unit.

Claims

1. An electronic device capable of switching power on and power off by a switch outside the electronic device, the electronic device comprising:

a determination unit configured to determine whether power is supplied from an AC power source or not;

a detection unit configured to detect a conductive state of the switch;

a second power source different from the AC power source;

an output unit; and

a control unit configured to perform at least one of cutting off power to be supplied to the output unit, supplying power from the AC power source to the output unit, and supplying power from the second power source to the output unit.

2. The electronic device of claim 1, wherein

the electronic device is connected to the AC power source via a power source supply line, the switch being connected in the power source supply line, and

the detection unit is configured to detect the conductive state of the switch via the power source supply line when the determination unit determines that no power is supplied from the AC power source.

3. The electronic device of claim 2, wherein

the detection unit is configured to apply a predetermined voltage to the power source supply line, and detect the conductive state of the switch by detecting an electric potential of the power source supply line.

4. The electronic device of claim 3, wherein

the control unit is configured to perform one of cutting off the power to be supplied to the output unit, supplying the power from the AC power source to the output unit, and supplying the power from the second power source to the output unit, based on the electric potential of the power source supply line.

5. The electronic device of claim 4, wherein

the control unit is configured to cut off the power to be supplied to the output unit when the detection unit detects the electric potential on the predetermined voltage, and supply the power from the second power source to the output unit when the detection unit detects no electric potential on the predetermined voltage and no power is supplied from the AC power source.

6. The electronic device of claim 3, wherein

the detection unit is configured to determine that the switch is conductive when a detection result of the electric potential is lower than the predetermined voltage by a predetermined value or more.

7. The electronic device of claim 3, wherein

the power source supply line comprises a hot wire and a ground wire, and the switch is configured to cause at least the hot wire to be conductive or cut off at least the hot wire, and

the electronic device further comprises:

a power source line connected to the hot wire and the ground wire; and

a switching element configured to change a conductive state of the power source line and the ground wire when the detection unit applies the predetermined voltage to the hot wire via the power source line.

8. The electronic device of claim 2, further comprising a power source line connected to the power source supply line,

wherein

the detection unit comprises:

a relay provided in the power source supply line and opened when the determination unit determines that no power is supplied from the AC power source;

a potential setting unit configured to set the power source line between the relay and the switch to a predetermined potential; and

a potential detecting unit configured to detect a conductive state of the switch, based on the electric potential set by the potential setting unit.

9. The electronic device of claim 8, wherein

the potential setting unit is supplied with power from the second power source.

10. The electronic device of claim 8, wherein

the determination unit comprises a voltage variation detecting unit configured to detect voltage variation of the power source line, and determine power supply and no power supply from the AC power source by detecting the voltage variation in a predetermined period.

11. The electronic device of claim 10, wherein

the potential detecting unit and the voltage variation detecting unit are configured to share:

a resistor connected to the power source line; and

a photo-coupler configured to detect a current flowing through the resistor and output a detection signal to the control unit.

12. The electronic device of claim 11, wherein

the control unit is configured to cause a resistance of the resistor to be smaller when no power is supplied from the AC power source, as compared with a state in which the power is supplied from the AC power source.

13. The electronic device of claim 8, wherein

the power source supply line comprises a hot wire and a ground wire, and the switch causes at least the hot wire conductive or cuts off at least the hot wire,

the power source line includes a first line connected to the determination unit and the detection unit, and a second line different from the first line, and

the electronic device further comprises a polarity switching unit configured to switches the power source line to connect the first line to the hot wire and connect the second line to the ground wire.

14. The electronic device of claim 13, wherein

the control unit is configured to automatically switch the polarity switching unit in accordance with a level of the voltage applied to the power source line.

15. The electronic device of claim 1, wherein

the output unit comprises a light emitting unit.

16. The electronic device of claim 15, wherein

the control unit is configured to control the light emitting unit to emit light in a first emission mode when the power is supplied from the AC power source and to emit light in a second emission mode when the power is supplied from the second power source.

17. The electronic device of claim 16, wherein

the light emitting unit is caused to flash at least one time in the second emission mode.

18. An electronic device capable of switching power on and power off by a switch outside the electronic device, the electronic device comprising:

a light emitting unit;

a second power source different from the AC power source; and

a control unit configured to, when no power is supplied from the AC power source and the switch is conductive, detect a conductive state of the switch, supply power from the second power source to the light emitting unit, and cause the light emitting unit to emit light in a second emission mode different from a first emission mode at a normal time.

19. The electronic device of claim 18, wherein

the light emitting unit is made to flash at least one time in the second emission mode.

20. An electronic device capable of switching power on and power off of an AC power source by a switch outside the electronic device, the electronic device comprising:

a light emitting unit;

a second power source different from the AC power source; and

a control unit configured to, when no power is supplied from the AC power source and the switch is conductive, detect a conductive state of the switch, supply power from the second power source to the light emitting unit, and cause the light emitting unit to emit light in a second emission mode different from a first emission mode at a normal time.