Microwave oven having generator power supply

Patent metadata

Field	Value
Publication number	US-11792897-B2
Application number	US-201616307232-A
Country	US
Kind code	B2
Filing date	Aug 22, 2016
Priority date	Aug 22, 2016
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

A microwave oven and a method of operating the same is provided herein. The method includes the steps of: sensing that a door of the microwave is in an open state; interrupting a power input to a generator power supply unit comprising a first converter, a first energy reserve, a second energy reserve located downstream from the first energy reserve, and a second converter located between the first and second energy reserves; detecting an input voltage; and disabling the second converter if the detected input voltage is less than a threshold voltage that is proportional to the detected input voltage, wherein disabling the second converter triggers the second energy reserve to discharge, and wherein the time necessary to discharge the second energy reserve is free of influence from the first energy reserve and is independent of the detected input voltage.

First claim

What is claimed is:

1. A microwave oven comprising:
a door movable between an open state and a closed state;
a microwave generator for generating microwaves, the microwave generator including at least one solid state amplifier; and
a generator power supply unit comprising the following components ordered from upstream to downstream:
a first converter for converting a power input to a power output;
a first energy reserve electrically coupled to the first converter for receiving the power output;
a second converter electrically coupled to the first energy reserve for converting the power output to a low voltage power output; and
a second energy reserve electrically coupled to the second converter for receiving the low voltage power output and supplying the low voltage power output to the at least one solid state amplifier of the microwave generator; and

a detection circuit configured to detect an input voltage and disable the second converter when the input voltage is less than a threshold voltage as a result of the door being in the open state, wherein disabling the second converter triggers the second energy reserve to discharge, and wherein the time necessary to discharge the second energy reserve is free of influence from the first energy reserve.

2. The microwave oven as claimed in claim 1 , further comprising an interruption circuit for electrically decoupling the generator power supply unit from a power source configured to supply the power input, and wherein the interruption circuit electrically decouples the generator power supply unit from the power source if the door is in the open state.

3. The microwave oven as claimed in claim 1 , wherein the detection circuit comprises a comparator for comparing the detected input voltage to the threshold voltage that is proportional to the detected input voltage.

4. The microwave oven as claimed in claim 3 , wherein the detection circuit transmits a switch-off signal for disabling the second converter if the detected input voltage is less than the threshold voltage.

5. The microwave oven as claimed in claim 4 , wherein the threshold voltage is maintained at a value greater than zero.

6. The microwave oven as claimed in claim 1 , wherein the power input comprises an AC power input, the power output comprises a DC power output, the low voltage power output comprises a low voltage DC power output, and the input voltage comprises a rectified peak AC input voltage.

7. The microwave oven as claimed in claim 1 , wherein the input voltage is detected upstream of the first converter.

8. The microwave oven as claimed in claim 1 , wherein the detection circuit bypasses components of the generator power supply unit located upstream from the second converter such that the first energy reserve remains charged while the discharging of the second energy reserve is underway.

Assignees

• Whirlpool Co
• Panasonic Corp
• Panasonic Holdings Corp

Inventors

• Gigante Alessandro
• Tarantino Giuseppe
• Rinaldi Matteo
• Wahlander David O

Classifications

• H05B6/686

  Circuits comprising a signal generator and power amplifier, e.g. using solid state oscillators · CPC title

• H02M1/322

  Means for rapidly discharging a capacitor of the converter for protecting electrical components or for preventing electrical shock · CPC title

• H05B6/76 Primary

  Prevention of microwave leakage, e.g. door sealings · CPC title

• H02M1/007

  Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826) · CPC title

• H05B6/68

  for monitoring or control · CPC title