JPH07226166A - Magnetron device integrated with electric power supply - Google Patents

Abstract

PURPOSE:To provide a magnetron device having small, safe, low noise and simple constitution by integrally housing a magnetron and an inverter electric power supply part in a shielding case. CONSTITUTION:A magnetron driving inverter electric power supply part 3 having a magnetron 1, a circuit board 3a, a power switch element 4 or the like is housed in a shielding case 2 composed of first, second and third shielding parts 2a, 2b and 2c. A cooling duct 5 to house a heat radiating body 6 contacting with the element 4 is provide between the first and the second shielding parts, and a through-capacitor 7 having a terminal being an electric power supply input terminal 7a by projecting outside from the case 2, a power control input terminal 8 and an antenna 1a, are provided. A radiator 10 is provided in a frame-shaped yoke 9 of the maghetron 1, and is cooled in common with the heat radiating body 6 by an air blowing fan.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power source integrated magnetron device for use in a microwave oven for household microwave ovens, an industrial microwave oscillator unit and the like.

[0002]

2. Description of the Related Art Conventionally, a ferroresonance type magnetron power source has been used, which has a large transformer and a large capacitor, which not only makes it heavy, but also causes dielectric breakdown due to high voltage. To prevent this, a considerable amount of mounting space was required.

[0003]

In recent years, an inverter power supply has been developed and can be reduced in size and weight.
The level of noise from the inverter power supply is high, and we are struggling with this measure. Moreover, when an inverter power supply is mounted on the magnetron device, a failure due to moding is likely to occur. In addition, in the inverter power supply, to prevent noise, the layout of each part, the shield, the way to run the cord,
Complex design considerations were required due to the use of ferrite cores and noise filters. Further, when the outer case of a microwave oven or the like is opened, the high-voltage portion is exposed, which sometimes causes an electric shock accident during production and inspection / repair.
Further, the magnetron device equipped with an inverter power source has a problem that it is likely to cause a moding failure.

The present invention has been made to solve such a problem, and provides a compact, safe, low noise, and power source integrated magnetron device having a simple structure.

[0005]

According to the present invention, there is provided a magnetron device integrated with a power source, in which a magnetron and an inverter power source part for driving the magnetron are housed in a shield case, an antenna is projected from the shield case, and the shield is provided. It has a configuration in which a power supply input terminal and a power control control input terminal are provided outside the case.

[0006]

According to the present invention, since the magnetron and the inverter power supply unit are housed in the shield case, it is not necessary to design the high voltage unit and the insulation distance, and noise can be suppressed sufficiently. it can.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a magnetron device with a power source integrated according to an embodiment of the present invention includes a magnetron 1 having an antenna 1a, a first shield portion 2a and a second shield portion 2b for shielding the magnetron. And a shield case 2 composed of a third shield portion 2c, a magnetron drive inverter power supply portion 3 housed in the shield case 2 and provided with a power switch element 4 and the like on a circuit board 3a, and a first shield portion 2a. Second shield part 2
b, a cooling duct 5 provided between the cooling duct 5, a power switch element radiator 6 provided in the cooling duct and in contact with the power switch element 4, and housed in a shield case 2. The power supply input terminal 7a has a feedthrough capacitor 7 provided outside the shield case 2 and a power control control input terminal 8 provided outside the shield case 2.

The magnetron 1 has a frame-shaped yoke 9 forming an exciting circuit thereof, and a radiator 10 is mounted on the outer peripheral surface of the magnetron 1 inside the frame-shaped yoke 9. The radiator 6 and the radiator 10 are commonly cooled by the blower fan 11 arranged on the cooling duct 5 side. The antenna 1 a is provided so as to project from the shield case 2.

FIG. 3 shows a circuit configuration of the inverter power supply unit 3. In FIG. 3, a commercial AC power source S of 100 V, 50 Hz / 60 Hz is rectified by a rectifier circuit D ₁ and smoothed by a smoothing circuit composed of capacitors C ₁ and C ₂ and a smoothing choke coil L. Capacitors C ₁ and C ₂ having a capacitance of several μF are used to prevent the power factor from being lowered, so that the pulsating waveform is supplied almost to the switching circuit SW.

The switching circuit SW includes a primary winding W ₁ ,
A high-frequency step-up transformer T having a secondary winding W ₂ , a tertiary winding W _3, and a heater winding H connected to the cathode of the magnetron 1, a resonant capacitor C ₃ connected in parallel with the primary winding W 1, It has a power switch element Q and a flywheel diode D _2, and has a voltage resonance type switching circuit configuration. A half-wave voltage doubler rectifier circuit including a capacitor C ₄ and a diode D ₃ is connected to the secondary winding W ₂ of the high frequency boosting transformer T. The output of the half-wave voltage doubler rectifier circuit is supplied to the anode of the magnetron 1. Signals such as a magnetron anode current signal, a power supply voltage signal on the primary winding side, a power supply current signal, and a voltage of the tertiary winding flowing at this time are sent to the control circuit N. The control circuit N stably controls the oscillation of the magnetron 1 by comparing (calculating) the above signal with an oscillation ON-OFF signal or a power control signal from an external input.

In such a magnetron device with integrated power source, the commercial AC power source S is connected to the power source input terminal 7a provided in the shield case 2, and the power control control input terminal 8 provided in the shield case 2 is provided with a predetermined voltage. By applying a signal, the oscillating operation and power control of the magnetron 1 are performed, and the microwave oscillates from the magnetron 1.

Further, when the moding occurs, an abnormal anode voltage (spike voltage) is generated in the magnetron 1. Therefore, as shown in FIG.
Is detected by the third winding W ₃ , and the comparator compares the detected voltage V ₁ with the reference voltage V _2, and if the spike voltage is abnormal, the operation of the magnetron 1 is stopped.

The moding detector is shown in FIG.
In addition to those shown in FIG. In FIG. 5, R ₅₁ , R ₅₂ , R ₅₃ , and R ₅₄ are resistors, C ₅₁ and C ₅₂ are capacitors, and the time constant indicated by the product of the resistors R ₅₁ and C ₅₁ is τ ₁ , and the resistor R _{5 3} and when the constants tau ₂ when represented by the product of the capacitor C _52, have a relationship of τ ₁ <τ _2, Although the constant operating voltage is the relation of V ₁ <V _2, when moding When a spike voltage is generated in the tertiary winding W ₃ , the relationship of V ₁ > V ₂ is changed.

According to the magnetron device integrated with the power supply of the embodiment of the present invention, unlike the conventional one, it is not necessary to consider the design of the routing of the high voltage part and the insulation distance. Further, in the product using the magnetron with integrated power supply according to the embodiment of the present invention, since the high-voltage portion is not exposed during manufacturing, maintenance and service, electric shock accident can be completely prevented. Further, since the inverter power supply unit 3 which is a noise generation source is shielded by the shield case 2 (FIG. 3) and the power supply input terminal 7a has a feedthrough capacitor structure, both radiation noise and conductive noise are sufficiently suppressed. can do.

Further, according to the magnetron device with integrated power supply of the embodiment of the present invention, the air cooling of the power switch element Q and the air cooling of the magnetron 1 can be performed by the common blower fan 11.

[0017]

As described above, according to the present invention,
Since the inverter power supply unit has a configuration that is integrated with the magnetron, it can be made compact, and because the inverter power supply unit is housed in a shield case, it is safe and can prevent noise emission to the outside. Moreover, it is possible to provide a magnetron device with an integrated power supply having a simple structure. INDUSTRIAL APPLICABILITY The present invention can be used not only in a microwave oven but also in a microwave oscillator application field, and the field of application thereof is large.

[Brief description of drawings]

FIG. 1 is a perspective view of a magnetron device with an integrated power supply, which is an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the same.

FIG. 3 is a circuit configuration diagram of an example of an inverter power supply unit.

FIG. 4 is a circuit configuration diagram of an example of a magnetron moding detection unit.

FIG. 5 is a circuit configuration diagram of another example of the magnetron moding detection unit.

[Explanation of symbols]

 1 Magnetron 1a Antenna 2 Shield Case 3 Inverter Power Supply Section 4 Power Switch Element 5 Cooling Duct 6 Power Switch Element Radiator 7 Feedthrough Capacitor 7a Power Input Terminal 8 Power Control Control Input Terminal

Claims (3)

[Claims] 1. A magnetron and an inverter power supply unit for driving the magnetron are housed in a shield case,
A magnetron device integrated with a power source, wherein an antenna is projected from the shield case and a power input terminal and a power control control input terminal are provided outside the shield case. 2. An inverter power supply unit includes a high frequency boosting transformer, a tertiary winding is provided on the high frequency boosting transformer, and the operation of the magnetron is stopped by detecting the anode voltage of the magnetron on the tertiary winding. The magnetron device with integrated power supply according to claim 1, further comprising a control circuit connected thereto. 3. The magnetron device with integrated power supply according to claim 1, wherein a feedthrough capacitor is housed in a shield case, and a power supply input terminal is constituted by a terminal of the feedthrough capacitor.