U.S. patent application number 10/406254 was filed with the patent office on 2003-10-09 for circuit for operating microwave oven.
Invention is credited to Han, Sung Jin, Kim, Wan Soo.
Application Number | 20030189041 10/406254 |
Document ID | / |
Family ID | 28036197 |
Filed Date | 2003-10-09 |
United States Patent
Application |
20030189041 |
Kind Code |
A1 |
Kim, Wan Soo ; et
al. |
October 9, 2003 |
Circuit for operating microwave oven
Abstract
Circuit for operating a microwave oven including a DC voltage
source, a switching part having at least two switching devices
electrically connected to the DC voltage source for switching a
voltage from the DC voltage source, controlling part for
controlling the switching part, a magnetron for generating a
microwave and a converting part for converting the voltage from the
DC voltage source to a voltage for operating the magnetron by
switching of the switching part, thereby permitting operation of
the microwave oven by using a car battery.
Inventors: |
Kim, Wan Soo;
(Kwangmyong-shi, JP) ; Han, Sung Jin; (Seoul,
KR) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
28036197 |
Appl. No.: |
10/406254 |
Filed: |
April 4, 2003 |
Current U.S.
Class: |
219/715 ;
219/702 |
Current CPC
Class: |
H05B 6/80 20130101; Y02B
40/00 20130101; H05B 6/683 20130101 |
Class at
Publication: |
219/715 ;
219/702 |
International
Class: |
H05B 006/66 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 4, 2002 |
KR |
2002-0018619 |
Claims
What is claimed is:
1. A circuit for operating a microwave oven comprising: a DC
voltage source; a switching part having at least two switching
devices electrically connected to the DC voltage source for
switching a voltage from the DC voltage source; a controlling part
for controlling the switching part; a magnetron for generating a
microwave; and a converting part for converting the voltage from
the DC voltage source to a voltage for operating the magnetron by
switching of the switching part.
2. The circuit as claimed in claim 1, wherein the DC voltage source
is a car battery source.
3. The circuit as claimed in claim 1, wherein the switching part
includes two or four switching devices.
4. The circuit as claimed in claim 3, wherein the switching device
includes a bipolar transistor and a diode connected in parallel to
each other.
5. The circuit as claimed in claim 4, wherein the switching devices
each having the bipolar transistor and the diode are connected in
parallel.
6. The circuit as claimed in claim 3, wherein the switching device
includes an MOSFET, a diode and a capacitor connected in
parallel.
7. The circuit as claimed in claim 6, wherein the switching devices
each having the MOSFET, the diode and the capacitor form a serial
resonant half-wave voltage doubler rectifier circuit or a serial
resonant full wave rectifier circuit.
8. The circuit as claimed in claim 1, wherein the converting part
is a transformer.
9. A circuit for operating a microwave oven comprising: a DC
voltage source; a first switching device connected to the DC
voltage source in series for switching a voltage from the DC
voltage source; a second switching device connected to the first
switching device in parallel for switching the voltage from the DC
voltage source; a controlling part for controlling the first, and
second switching devices: a magnetron for generating a microwave;
and a converting part connected between the DC voltage source and a
node between the first and second switching devices for converting
the voltage from the DC voltage source to a voltage for operating
the magnetron by switching of the first and second switching
devices.
10. The circuit as claimed in claim 9, wherein each of the first,
and second switching devices includes a bipolar transistor and a
diode connected in parallel to each other.
11. The circuit as claimed in claim 9, wherein the converting part
is connected to an anode of the DC voltage source.
12. A circuit for operating a microwave oven comprising: a DC
voltage source; first and second switching devices connected to the
DC voltage source in series for switching a voltage from the DC
voltage source; a controlling part for controlling the first, and
second switching devices; a magnetron for generating a microwave;
and a converting part connected between the DC voltage source and a
node between the first and second switching devices for converting
the voltage from the DC voltage source to a voltage for operating
the magnetron by switching of the first and second switching
devices.
13. The circuit as claimed in claim 12, wherein each of the first,
and second switching devices includes an MOSFET, a diode and a
capacitor connected in parallel to one another.
14. The circuit as claimed in claim 12, wherein the converting part
is connected to a cathode of the DC voltage source.
15. A circuit for operating a microwave oven comprising: a DC
voltage source; first and second switching devices connected to the
DC voltage source in series for switching a voltage from the DC
voltage source; third and fourth switching devices connected to the
first and second switching devices in parallel for switching the
voltage from the DC voltage source; a controlling part for
controlling the first, second, third and fourth switching devices;
a magnetron for operating a microwave; and a converting part
connected between a first node between the first and second
switching device and a second node between the third and fourth
switching devices for converting the voltage from the DC voltage
source to a voltage for operating the magnetron by switching of the
first, second, third and fourth switching devices.
16. The circuit as claimed in claim 13, wherein each of the first,
second, third and fourth switching devices includes an MOSFET, a
diode and a capacitor connected in parallel to one another.
Description
[0001] This application claims the benefit of the Korean
Application No. P20021-18619 filed on Apr. 4, 2002, which is hereby
incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a circuit for operating a
microwave oven, and more particularly, to an inverter circuit which
can operate a microwave oven by using a DC voltage.
[0004] 2. Background of the Related Art
[0005] Recently, enhancement of an energy consumption efficiency
and performance of most home appliances, such as electric rice
cookers, air conditioners, refrigerators and the like, are sought
by applying an inverter operating system thereto. It is because
users' demand for home appliances that have a high energy
consumption efficiency, an improved performance and convenience in
use becomes the greater, as goods for convenience of life, such as
the electric rice cookers, air conditioners, refrigerators and the
like, are used the wider gradually.
[0006] Such an inverter operating system is applied to the
microwave oven, too. The microwave oven heats an object by
directing microwave generated from a current to the object. For
generation of the microwave, an inverter operating system of
control is employed.
[0007] FIG. 1 illustrates a related art circuit for operating a
microwave oven.
[0008] Referring to FIG. 1, a related art inverter circuit for
operating a microwave oven is provided with a rectifying circuit 15
for rectifying an AC current from an AC power source 10, which
rectified current is provided to a primary side of a transformer
through the inductor 20. There is a magnetron 40 on a secondary
side of the transformer 25 for generating microwave. That is, the
magnetron 40 is operative from the voltage induced at the secondary
side of the transformer 25 for generating the microwave.
[0009] A primary side voltage of the transformer 25 is controlled
by a power switching part 30. The power switching part 30 is turned
on/off in response to a PWM control signal generated at an inverter
operating part 55 based on an output control signal from the
microcomputer 35, to control a primary supply voltage of the
transformer 25.
[0010] A current to the magnetron 40 is detected at a current
transformer 45, rectified at a rectifying circuit 50, and
forwarded. A signal of a current intensity to the magnetron 40
detected at the current transformer 45 is provided to the
microcomputer 35.
[0011] In the meantime, an anode of the magnetron 40 has no
current, but a high voltage provided thereto from the transformer
25, until a heater in the magnetron 40 is heated enough to emit
thermal electrons. This state is a non-oscillation region of the
magnetron 40, and it takes a certain time period (about 2 seconds)
until the heater in the magnetron 40 makes a regular emission of
the thermal electrons enough to generate the microwave.
[0012] That is, only after the regular oscillation of the magnetron
40 is made by the heater, the current flow to the anode of the
magnetron 40 starts. This current is called as an anode current,
and a product of the anode current and an anode voltage is a power
P provided to the magnetron 40. A product of the power P to an
efficiency of the magnetron 40 represents an intensity of the
microwave from the magnetron 40.
[0013] Therefore, the current intensity to the magnetron 40 is in
correspondence to a microwave output, such that if the current
intensity is high, the microwave output is high, and if the current
intensity is low, the microwave output is low.
[0014] That is, the current intensity detected at the current
transformer 45 is used for controlling the microwave output as the
current intensity is provided to the microcomputer 35 to control
the current intensity to the magnetron 40.
[0015] However, the related art circuit for operating a microwave
oven has the following problems.
[0016] Because the related art microwave oven is only operative on
an utility AC power, operation of the magnetron in outdoor without
the utility AC power is not possible, and operation of the
magnetron is also not possible in a black out.
SUMMARY OF THE INVENTION
[0017] Accordingly, the present invention is directed to a circuit
for operating a microwave oven that substantially obviates one or
more of the problems due to limitations and disadvantages of the
related art.
[0018] An object of the present invention is to provide a circuit
for operating a microwave oven in which the microwave oven is
controlled by using a DC power such as a power source for a
car.
[0019] Additional features and advantages of the invention will be
set forth in the description which follows, and in part will be
apparent from the description, or may be learned by practice of the
invention. The objectives and other advantages of the invention
will be realized and attained by the structure particularly pointed
out in the written description and claims hereof as well as the
appended drawings.
[0020] To achieve these and other advantages and in accordance with
the purpose of the present invention, as embodied and broadly
described, the circuit for operating a microwave oven includes a DC
voltage source, a switching part having at least two switching
devices electrically connected to the DC voltage source for
switching a voltage from the DC voltage source, a controlling part
for controlling the switching part, a magnetron for generating a
microwave, and a converting part for converting the voltage from
the DC voltage source to a voltage for operating the magnetron by
switching of the switching part.
[0021] The DC voltage source is a car battery source.
[0022] The switching part includes two or four switching devices.
The switching device includes a bipolar transistor and a diode
connected in parallel to each other. The switching devices each
having the bipolar transistor and the diode are connected in
parallel.
[0023] The switching device includes an MOSFET, a diode and a
capacitor connected in parallel.
[0024] The switching devices each having the MOSFET, the diode and
the capacitor form a serial resonant half-wave voltage doubler
rectifier circuit or a serial resonant full wave rectifier
circuit.
[0025] In another aspect of the present invention, there is
provided a circuit for operating a microwave oven including a DC
voltage source, a first switching device connected to the DC
voltage source in series for switching a voltage from the DC
voltage source, a second switching device connected to the first
switching device in parallel for switching the voltage from the DC
voltage source, a controlling part for controlling the first, and
second switching devices, a magnetron for generating a microwave,
and a converting part connected between the DC voltage source and a
node between the first and second switching devices for converting
the voltage from the DC voltage source to a voltage for operating
the magnetron by switching of the first and second switching
devices.
[0026] Each of the first, and second switching devices includes a
bipolar transistor and a diode connected in parallel to each
other.
[0027] In further aspect of the present invention, there is
provided a circuit for operating a microwave oven including a DC
voltage source, first and second switching devices connected to the
DC voltage source in series for switching a voltage from the DC
voltage source, a controlling part for controlling the first, and
second switching devices, a magnetron for generating a microwave,
and a converting part connected between the DC voltage source and a
node between the first and second switching devices for converting
the voltage from the DC voltage source to a voltage for operating
the magnetron by switching of the first and second switching
devices.
[0028] Each of the first, and second switching devices includes an
MOSFET, a diode and a capacitor connected in parallel to one
another.
[0029] In still further aspect of the present invention, there is
provided a circuit for operating a microwave oven including a DC
voltage source, first and second switching devices connected to the
DC voltage source in series for switching a voltage from the DC
voltage source, third and fourth switching devices connected to the
first and second switching devices in parallel for switching the
voltage from the DC voltage source, a controlling part for
controlling the first, second, third and fourth switching devices,
a magnetron for generating a microwave, and a converting part
connected between a first node between the first and second
switching device and a second node between the third and fourth
switching devices for converting the voltage from the DC voltage
source to a voltage for operating the magnetron by switching of the
first, second, third and fourth switching devices.
[0030] Each of the first, second, third and fourth switching
devices includes an MOSFET, a diode and a capacitor connected in
parallel to one another.
[0031] It is to be understood that both the foregoing general
description and the following detailed description are exemplary
and explanatory and are intended to provide further explanation oil
the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention:
[0033] In the drawings:
[0034] FIG. 1 illustrates a circuit diagram for describing a
related art circuit for operating a microwave oven; and
[0035] FIGS. 2 to 4 illustrate circuit diagrams each for describing
a circuit for operating a microwave oven in accordance with one of
different preferred embodiments of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0036] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings. FIGS. 2 to 4 illustrate
circuit diagrams each for describing a circuit for operating a
microwave oven in accordance with one of different preferred
embodiments of the present invention.
[0037] Referring to FIG. 2, the circuit for operating a microwave
oven in accordance with a preferred embodiment of the present
invention is provided with a DC voltage source DC, for an example,
a car battery which is used widely, for cooking food in outdoor by
using the microwave oven.
[0038] The circuit for operating a microwave oven in accordance
with a preferred embodiment of the present invention includes a
switching part 100 having at least two electrically connected
switching, devices S1 and S2 for switching a voltage from the DC
voltage source DC, a controlling part 110 for controlling the
switching devices S1 and S2, a magnetron 130 for generating a
microwave, a converting part 120 for converting, the voltage into a
voltage or operating the magnetron 130 by turning, on/off of the
switching part 100.
[0039] That is, the embodiment shown in FIG. 2 includes the DC
voltage source DC. the first switching device S1 connected to the
DC voltage source in series for switching the voltage of the DC
voltage source, the second switching device S1 connected to the
first switching device S1 in parallel for switching, the voltage of
the DC voltage source, the controlling part 110 for controlling the
first and second switching devices S1 and S2, the magnetron 130 for
generating the microwave, and the converting part 120 connected to
the DC voltage source and a node between the first and second
switching devices S1 and S2 for converting the voltage from the DC
voltage source to a voltage which can operate the magnetron
according to switching of the first and second switching devices S1
and S2.
[0040] The first and second switching devices S1 and S2 are a
bipolar transistor and a diode respectively connected in
parallel.
[0041] The converting part 120, a transformer, is connected to the
anode of the DC voltage source.
[0042] Though not shown, the controlling part 110 includes an
inverter operating part and a microcomputer, so that the switching
devices S1 and S2 are turned on/off in response to control signals
provided from the inverter operating part based on an output
control signal from the microcomputer, for controlling the primary
side supply voltage of the converter 120.
[0043] The operation will be described in more detail. The DC
voltage source voltage DC is made to be provided to the primary
side of the converting part 120 as a pulsating voltage through the
rectifying circuit (not shown). The pulsating voltage is turned
into an alternating voltage by switching of the switching part 100
before being provided to the primary side of the converting part
120. Since an intensity of the current i switched is as high as
about 139A, the present invention formulates the switching part 100
with the two switching devices.
[0044] Accordingly, the secondary side of the converting part 120
is converted into a voltage range enough to operate the magnetron
130 in proportion of a number of windings, and to make the
magnetron 130 to generate the microwave.
[0045] The current to the magnetron 130 is detected by the current
transformer 140, and the detected current is converted through the
rectifying circuit 150 before being forwarded. A signal of an
intensity of the current to the magnetron 130 detected at the
current transformer 140 is provided to the microcomputer in the
controlling part 110.
[0046] As described before, the current intensity detected at the
current transformer 140 is provided to the microcomputer for
controlling the current intensity to the magnetron, to control
microwave output.
[0047] Since the present invention operative thus can operate a
microwave oven by using a power source, such as a car battery, food
can be cooked even in outdoor conveniently.
[0048] Next. FIG. 3 illustrates a circuit diagram for describing
another preferred embodiment of the present invention, wherein
parts the same with FIG. 2 will be represented with the same
reference symbols.
[0049] Referring to FIG. 3, the two switching devices S1 and S2 of
the switching part 100 are provided in serial resonant half-wave
rectification circuits each inclusive of an MOSFET transistor, a
diode, and a capacitor connected in parallel.
[0050] That is, the embodiment in FIG. 3 includes the DC voltage
source DC, first, and second switching devices S1 and S2 connected
to the DC voltage source in series for switching a voltage provided
from the DC voltage source, a controlling part 110 for controlling
the first and second switching devices S1 and S2, a magnetron 30
for generating a microwave, and a converting part 120 connected to
the DC voltage source and a node between the first and second
switching devices S1 and S2 for converting the voltage from the DC
voltage source to a voltage which can operate the magnetron
according to switching of the first and second switching devices S1
and S2.
[0051] Each of the first and second switching devices S1 and S2
includes an MOSFET Transistor, a diode, and a capacitor connected
in parallel. The converting part 120 connected to the DC voltage
source is connected to a cathode of the DC voltage source.
[0052] Since the embodiment of FIG. 3 has a current to the
switching device S1 or S2 as high as approx, 118A, the MOSFET
transistor is employed, which has excellent current handling
capability and switching speed.
[0053] Upon subjecting a voltage of approx, 2 KV, a secondary
voltage of the converting part 120 provided by switching of the
switching devices, to a half-wave voltage doubler rectification and
application to the magnetron 130, a microwave energy is produced to
cook the food.
[0054] FIG. 4 illustrates a circuit diagram for describing a
circuit for operating a microwave oven in accordance with another
preferred embodiment of the present invention.
[0055] Referring to FIG. 4, four switching devices S1.about.S4 of
the switching part 100 are provided in serial resonant full wave
rectifier circuits.
[0056] That is, the embodiment in FIG. 4 includes the DC voltage
source DC, first, and second switching devices S1 and S2 connected
to the DC voltage source in series for switching a voltage provided
from the DC voltage source, third, and fourth switching devices S3
and S4 connected to first, and second switching devices S1 and S2
in parallel for switching a voltage provided from the DC voltage
source, a controlling part 110 for respectively controlling the
first second, third and fourth switching devices S1, S2, S3 and S4,
a magnetron 130 for generating a microwave, and a converting part
120 connected to a first node between the first and second
switching n devices S1 and S2 and a second node between the third
and fourth switching devices S3 and S4 lot converting the voltage
from the DC voltage source to a voltage which can operate the
magnetron according to switching of the first, second, third, and
fourth switching devices S1, S2, S3 and S4.
[0057] Each of first, second, third, and fourth switching devices
S1, S2, S3 and S4 includes an MOSFET transistor, a diode and a
capacitor connected in parallel.
[0058] Since the embodiment of FIG. 4 has a current to the
switching device S1, S2, S3 or S4 as high as approx. 59A, alike the
case of FIG. 3, the MOSFET transistor is employed, which has
excellent current handling capability and switching speed.
[0059] Upon subjecting a voltage of approx, 2 KV, a secondary
voltage of the converting part 120 provided by switching of the
switching devices, to a half-wave voltage doubler rectification and
application to the magnetron 130, a microwave energy is produced,
to cook the food.
[0060] As has been described, the circuit for operating a microwave
oven of the present invention has the following advantages.
[0061] The operating circuit, which can generate a microwave energy
from a magnetron by using DC power source, such as car battery
which is used widely, permits convenient outdoor cooking of food as
well as convenient cooking of food in a black out, by using a car
battery.
[0062] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the invention. Thus,
it is intended that the present invention cover the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *