Power supply apparatus

• US 6,434,024 B2
• Filed: 04/06/2001
• Issued: 08/13/2002
• Est. Priority Date: 04/07/2000
• Status: Expired due to Term

• Current Assignee: Saturn Licensing LLC (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Shirato, Keiji
• Primary Examiner(s): NGUYEN, MATTHEW VAN
• Application Number:
  US09/827,445
• Publication Number:
  US 20010055216A1
• Time in Patent Office: 494 Days
• Field of Search: 363/16, 363/20, 363/21.01, 363/21.07, 363/21.15, 363/95, 363/97, 363/131
• US Class Current: 363/21.07
• CPC Class Codes: H02J 9/007 Detection of the absence of a load
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A power supply apparatus is provided with a power supply transformer; excitation circuit portions provided at a primary side of the power supply transformer, for exciting the power supply transformer by means of a commercial power supply; and control circuit portions provided at a secondary side of the power supply transformer, for starting operation by the power supply transformer having entered an excited state and for intermittently operating the excitation circuit portion 50. Thereby, power in a waiting state can be suppressed at maximum and energy saving can be executed further efficiently.

Claims

1. A power supply apparatus, comprising:

a power supply transformer;

an excitation circuit portion to be provided on a primary side of said power supply transformer and to excite said power supply transformer with an alternating current power supply; and

a control circuit portion provided on a secondary side of said power supply transformer, to start an operation by said power supply transformer in an excitation state, and to cause said excitation circuit portion to operate intermittently;

wherein said control circuit portion halts the excitation operation of said power supply transformer by said excitation circuit portion when the charged voltage value of a secondary side voltage accumulating capacitor charged by said power supply transformer in said excitation state exceeds a first threshold level; and

after said power supply transformer halts the excitation operation, said control circuit portion resumes the excitation operation of said power supply transformer by said excitation circuit portion when a charged voltage value of said secondary side voltage accumulating capacitor drops due to a discharge to reach lower than a second threshold level.

2. A power supply apparatus, comprising:

a power supply transformer;

an excitation circuit portion to be provided on a primary side of said power supply transformer and to excite said power supply transformer with an alternating current power supply;

said excitation circuit; and

a control circuit portion provided on a secondary side of said power supply transformer, to start an operation by said power supply transformer in an excitation state, and to cause said excitation circuit portion to operate intermittently;

said excitation circuit portion including;

a switching element to switch supply of said alternating current power supply to said power supply transformer;

a direct current voltage generating circuit to generate a direct current voltage for causing said switching element to operate, and supplying said switching element with said direct current voltage when supply of said alternating current voltage supply starts, said direct current voltage generating circuit including a switching accumulating capacitor to supply said switching element with a charged voltage of said switching voltage accumulating capacitor by said alternating current voltage supply; and

a photocoupler to insulate said excitation circuit portion and said control circuit portion in between and to intermediate a control signal outputted from said control circuit portion to said switching element;

wherein said control circuit portion resumes the excitation operation of said power supply transformer by said excitation circuit portion with said photocoupler of said excitation circuit portion to intermediate when a charged voltage value of said secondary side voltage accumulating capacitor drops due to a discharge to reach lower than a second threshold.

3. The power supply apparatus according to claim 2, wherein said control circuit portion controls a predetermined current to be supplied to said photocoupler in case of halting the excitation operation of said power supply transformer by said excitation circuit portion.

4. The power supply apparatus according to claim 3, wherein said control circuit portion is selected to have a large time constant including said secondary side voltage accumulating capacitor.

5. The power supply apparatus according to claim 4, wherein said photocoupler is in an ON condition, and said switching element supplies said alternating current power to said transformer.

6. The power supply apparatus according to claim 5, wherein said witching element is a field effect transistor to switch supply of said alternating current power supply.

7. The power supply apparatus according to claim 6, wherein a momentary switch is provided in parallel on an output end in order to make said switching element be in an ON state by hand operation.

8. The power supply apparatus according to claim 2 wherein said switching element includes a plurality of bridge diodes and a FET switch connecting them in a middle point.

9. The power supply apparatus according to claim 2 wherein said switching element includes a plurality of bridge diodes and a thyristor switch connecting them in a middle point.

10. The power supply apparatus according to claim 2 wherein said switching element includes a plurality of bridge diodes and an IGBT connecting them in a middle point.

11. The power supply apparatus according to claim 8, wherein said switching element includes two FET connected to each other in series, a limiting resistor connected in series with the two FET, and a triac iconnected in parallel with the two FET and the limiting resistor.