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US 10,566,907 B1Granted
Power supply apparatus and image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorMinoru Hayasaki
Life of this patent
Estimating the term…
Abstract
The power supply apparatus having a current resonance circuit includes a charge unit connected to a primary winding of a transformer, and storing electric charge, and a connection unit connected in series with the charge unit, and configured to switch the charge unit between a connecting state in which one of charging and discharging is enabled, and a non-connecting state, and after making the connection unit into the connecting state, while a current is flowing into either one of the first diode and the second diode, the first control unit performs transition from a halt period to an operating period of a switching operation by turning ON the switching element of the one of the first diode and the second diode, the current being flowing into the one of the first diode and the second diode.
Claims8
A power supply apparatus comprising:
- a transformer including a primary winding and a secondary winding;
- a first switching element connected in series with the primary winding;
- a first diode connected in parallel with the first switching element;
- a second switching element connected in parallel with the primary winding;
- a second diode connected in parallel with the second switching element;
- a first capacitor connected in series with a resistor and the primary winding, the first capacitor with the resistor connected in parallel with a series circuit of the second switching element and the primary winding;
- a first control unit configured to control a switching operation of the first switching element and the second switching element, wherein in a case where a voltage output from the power supply apparatus is a first voltage, the first control unit continuously drives the first switching element and the second switching element, and in a case where the voltage output from the power supply apparatus is a second voltage smaller than the first voltage, the first control unit is capable of controlling the switching operation so as to repeat an operating period in which the first switching element and the second switching element are continuously driven, and a halt period in which the first switching element and the second switching element are stopped;
- a charge unit connected to the primary winding, and configured to store electric charge;
- and
- a connection unit connected in series with the charge unit, and configured to switch the charge unit between a connecting state in which one of charging and discharging is enabled, and a non-connecting state,
- wherein after a state of the connection unit is switched to the connecting state, during a period in which a current is flowing into either one of the first diode and the second diode, the first control unit performs transition from the halt period to the operating period by turning ON the first switching element or the second switching element on a side of the either one of the first diode and the second diode into which the current is flowing,
- wherein the charge unit is a second capacitor connected in series with the second switching element,
- wherein the connection unit includes a third switching element, and a third diode connected in parallel with the third switching element, and
- wherein the first control unit controls the second switching element to turn on during the current flows into the second diode by discharging electric charge in the second capacitor in a turn-on state of the third switching element.
11 more elements
An image forming apparatus comprising:
- an image forming unit configured to perform image formation on a recording material;
- and
- a power supply apparatus configured to supply electric power to the image forming apparatus so as to perform the image formation,
- the power supply apparatus comprising:
- a transformer including a primary winding and a secondary winding;
- a first switching element connected in series with the primary winding;
- a first diode connected in parallel with the first switching element;
- a second switching element connected in parallel with the primary winding;
- a second diode connected in parallel with the second switching element;
- a first capacitor connected in series with a resistor and the primary winding, the first capacitor with the resistor connected in parallel with a series circuit of the second switching element and the primary winding;
- a first control unit configured to control a switching operation of the first switching element and the second switching element, wherein in a case where a voltage output from the power supply apparatus is a first voltage, the first control unit continuously drives the first switching element and the second switching element, and in a case where the voltage output from the power supply apparatus is a second voltage smaller than the first voltage, the first control unit is capable of controlling the switching operation so as to repeat an operating period in which the first switching element and the second switching element are continuously driven, and a halt period in which the first switching element and the second switching element are stopped;
- a charge unit connected to the primary winding, and configured to store electric charge;
- and
- a connection unit connected in series with the charge unit, and configured to switch the charge unit between a connecting state in which one of charging and discharging is enabled, and a non-connecting state,
- wherein after a state of the connection unit is switched to the connecting state, during a period in which a current is flowing into either one of the first diode and the second diode, the first control unit performs transition from the halt period to the operating period by turning ON the first switching element or the second switching element on a side of the either one of the first diode and the second diode into which the current is flowing,
- wherein the charge unit is a second capacitor connected in series with the second switching element,
- wherein the connection unit includes a third switching element, and a third diode connected in parallel with the third switching element, and
- wherein the first control unit controls the second switching element to turn on during the current flows into the second diode by discharging electric charge in the second capacitor in a turn-on state of the third switching element.
15 more elements
Dependencies are inferred from the claim text.