Power source apparatus

• US 20040080304A1
• Filed: 10/14/2003
• Published: 04/29/2004
• Est. Priority Date: 10/23/2002
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Takehara, Nobuyoshi
• Granted Patent: US 6,967,415 B2
• Time in Patent Office: Days
• US Class Current: 323/282
• CPC Class Codes: H02M 1/36 Means for starting or stopping converters

Abstract

A power source apparatus comprising: a direct current power source to output a first voltage; a load driven with a second voltage higher than the first voltage; a booster converter to boost an output from the direct current power source to the second voltage; and a control circuit, arranged to operate at a voltage higher than the first voltage, to control the booster converter. A power storage unit for storing an output from the booster converter is provided, and a reverse current blocking unit is provided between the power storage unit and the load, for preventing supply of electric power stored in the power storage unit to the load. When the booster converter is started, the electric power is supplied from the power storage unit to the control circuit, and when the booster converter has started, the electric power is supplied from the booster converter to the control circuit.

Claims

1. A power source apparatus comprising:

a direct current power source to output a first voltage;

a load driven with a second voltage higher than the first voltage;

a booster converter to boost an output from the direct current power source to the second voltage;

a control circuit, arranged to operate at a voltage higher than the first voltage, to control the booster converter;

power storage means for storing an output from the booster converter;

reverse current blocking means, provided between the power storage means and the load, for preventing supply of electric power stored in the power storage means to the load; and

switch means for, when the booster converter is started, supplying the electric power from the power storage means to the control circuit, and when the booster converter has started, supplying the electric power from the booster converter to the control circuit.

2. The power source apparatus according to claim 1, wherein the switch means stops power supply to the control circuit when the voltage outputted from the direct current power source is lowered or when the load is not connected.

3. The power source apparatus according to claim 1, wherein the direct current power source is one of a fuel battery, a solar cell and a chemical cell.

4. The power source apparatus according to claim 1, wherein the direct current power source is constructed with a single cell which is not serially connected.

5. The power source apparatus according to claim 1, wherein the switch means automatically supplies the electric power from the power storage means to the control circuit when connected to the direct current power source.

6. The power source apparatus according to claim 1, wherein in the switch means, a user manually selects a first state to supply the electric power from the power storage means to the control circuit, and when the booster converter has started, a second state to supply the electric power from the booster converter to the control circuit.

7. The power source apparatus according to claim 1, wherein in the switch means, a first state to supply the electric power from the power storage means to the control circuit, and when the booster converter has started, a second state to supply the electric power from the booster converter to the control circuit, are selected with a timer.

8. The power source apparatus according to claim 1, wherein the reverse current blocking means is a diode.

9. A control method for controlling a power source apparatus having:

a direct current power source to output a first voltage;

a load driven with a second voltage higher than the first voltage;

a booster converter to boost an output from the direct current power source to the second voltage;

a control circuit, arranged to operate at a voltage higher than the first voltage, to control the booster converter; and

power storage means for storing an output from the booster converter, comprising the steps of;

preventing supply of electric power stored in the power storage means to the load; and

when the booster converter is started, supplying the electric power from the power storage means to the control circuit, and when the booster converter has started, supplying the electric power from the booster converter to the control circuit.