JPS618892A - High frequency heating device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a high-frequency heating device equipped with a so-called cleaning heater-equipped humidity sensor.

Structure of the conventional example and its problems FIG. 1 is an electrical circuit diagram of a high frequency heating device showing a conventional example.

One side of the AC 100V input from the controller 1 is input to the primary side of the high voltage transformer 2, and is boosted to a high voltage.
It is supplied to the voltage circuit 3 and generates a high frequency. The other is supplied to low voltage transformer A4. Low pressure 1 Lannes A4
The coil A5 on the secondary side generates a heater voltage for the display tube 6. The coil B7 is a coil having an intermediate tap 8, and after each half-wave rectification and smoothing are performed, a positive voltage with respect to the intermediate tap 8, which is a reference potential, is supplied to the control unit 9.

A negative voltage is supplied to the display tube 6. The coil CIO applies voltage to a heater 12 that heats and cleans dirt adhering to a humidity sensor 11 that detects steam information generated from an object to be heated. The heater 12 is controlled by a signal from the control section 9, and is controlled on and off by a triac 13, which is a gate driver element.

The temperature control section 9 receives information from the humidity sensor 11 and performs heating control, and also performs display control on the display tube 6.

Control unit 9 also controls relay A14 and relay BL5.

Conventionally, the power supply of the heater 12 for sensor heating and cleaning was controlled on and off by the triac 13, which is a gate trigger element, so a dedicated coil C10 was required, and the power supply of the heater 12 for sensor heating and cleaning was controlled on and off. There are many terminals,
This had the disadvantage that an inexpensive streamlined transformer with a small total number of terminals could no longer be used. Also, since the point after passing through the triac 13 or heater 12 from the wire ring C10 is connected to the extremely low level of the control unit 9, the voltage seen from the reference potential becomes large, which may prevent electric shock. ,
, *! ;! i:l″Jm&&′itz″″・26
1.1 "0゛0101 semiconductor) 1□ ") Since it is connected to the reference potential by tracing the triac 13, which is an element, 10,000 - other '% and /) (j When the final state occurs , there was a risk that the semiconductor could generate heat and cause a fire.

Purpose of the Invention The present invention solves the above-mentioned conventional drawbacks, and aims to improve the safety against electric shock and fire of a high-frequency heating device equipped with a (humidity) sensor equipped with a device for heating and cleaning dirt such as oil, and to reduce noise. The aim is to improve trust in customers and achieve significant cost reductions.

Structure of the Invention In order to achieve the above object, the high frequency heating device of the present invention is used as a sensor that detects information such as steam generated from an object to be heated by heating it, and cleans dirt attached to the sensor by heating it. One end of the heater is shared with the guard ring provided around the sensor terminal (one of the heaters is used, and the heater is switched on and off using a triac, which is a gate trigger element. Ee-1;'(D-@l IJ111 part 0JJJ
! (sl: #i8Kf), connect the other terminal to the triac, and supply the reference potential to the control unit. This has the effect that the voltage from the terminal is kept low and there is no need to worry about electric shock.

Furthermore, the reference potential on the secondary side of the low-voltage transformer, the power supply reference supplied to the control unit, and the power supply reference supplied to the heater are exactly the same, and the reference potential does not drop to the reference potential through parts such as semiconductors. This also has the effect of completely eliminating the fear of fire, etc. as in the example.

DESCRIPTION OF EMBODIMENTS An example of the present invention will be described below with reference to the drawings.

In FIG. 2, the operating spring /l/ of the high frequency heating device 16 is
An electronic control circuit device 18 is attached to 17 . The control unit 9 in the electronic control circuit device 18 is an operating spring)
Information from v17 and cooking information from humidity sensor 11 are input, and magneto 719 is controlled intermittently. The propeller fan (fan motor 20) that cools the magnetron 19
) The cooling air enters the heating chamber 21, and the above-mentioned humidity sensor 11 detects the steam coming out from the heated object 22, and feeds back the information to the control section 9.

FIG. 3 shows an electrical circuit diagram of the high frequency heating device 16.

One side of the AC 100V input from the outlet 1 is input to the primary side of the high voltage transformer 20, and after being boosted to a high voltage, it is supplied to the high voltage circuit 3, and the magnetron 19 generates υ high frequency.

The other one is supplied to the low voltage transformer B23.

A coil D24 on the secondary side of the low-pressure lance B23 generates a heater voltage for the display tube 6. The wire E25 generates the cathode potential of the display tube 6 by means of a negative power supply composed of an electric current supplied to the control section 9, a diode 26, and an electrolytic capacitor 27.

The coil F28 applies a voltage to the heater 12 which heats and cleans dirt adhering to the humidity sensor 11 which detects steam information generated from the heated object.

One end of the heater 12 is at the same reference potential as the control unit 9, and the voltage phase applied to the control unit 9 from this reference potential is
The voltage phases applied to the heater 12 are configured to be exactly the same, and the voltage on the secondary side of the low voltage trannu B23 is the same as that of the trannu E.
25 and the wire ring F26 are A:Ro'#5 voltage, so the line voltage is kept low and the configuration is extremely safe from the standpoint of electric shock.

Further, the heater 12 is turned on and off by a triac 13 which is a gate trigger element, and its triac 13
A control signal to the control unit 9 is outputted from the control unit 9.

FIG. 4 is an enlarged detailed view of the humidity sensor 11, and shows the humidity detection section 2.
A heater 12 is installed around 9 to heat and clean the attached dirt. Since the humidity detection section 29 has a high impedance of several tens of M (l), a guard ring 31 is attached to the swivel of the drawer section 30, and one end of the guard ring 31 is connected to one terminal of the heater 12. There is.

In this way, the reference potential on the secondary side of the low voltage transformer B23, the reference potential supplied to the control unit 9, and the I
This is exactly the same as the supplied reference potential, and unlike the conventional example, there is also the effect that there is no risk of fire due to the reference potential falling through parts such as semiconductors.

Furthermore, with regard to external noise, the voltage phase supplied to each part on the secondary side of the low voltage transformer is the same, so noise countermeasures on the secondary side of the low voltage tiger 77 can be easily implemented. When the phase of each part as seen from the front and the reference potential are different, a lot of time and effort is spent removing noise (because noise components occur at various phases and voltages). has also been greatly improved.

In addition, the number of coils on the secondary side of the low-voltage tiger 77 can be reduced by two, from seven in the conventional example to five, which makes it possible to use an inexpensive streamlined transformer, which is also significant in terms of cost.
I was able to improve it.

Effect of the invention As described above, according to the present invention, the following effects are obtained.

(1) Since the reference potential of the voltage supplied from the secondary side of the low-voltage transformer 77 to each circuit is common, and the voltage phase of each coil is the same, the secondary side of the low-voltage transformer
The line voltage can be kept low, making it extremely safe in terms of electric shock.

(2)' Since the reference potential of the voltage supplied to each circuit from the secondary side of the low-voltage transformer is shared, and no components such as semiconductors are passed through, there is no fear of ignition of semiconductors or fires in the event of an abnormality.

(3) The base voltage potential of the voltage supplied to each circuit from the secondary side of the low-voltage transformer is made common, and the voltage level of each coil is set as follows:
[Since 1 is rotated, it is easy to analyze external noise components, and a strong control circuit that can withstand noise can be easily constructed at low cost.

(4) By sharing the voltage phase and reference potential supplied to each circuit from the low voltage 1~lamp secondary side, the number of transformer terminals on the secondary side can be greatly reduced, resulting in inexpensive rationalization. can be used.

[Brief explanation of drawings]

Fig. 1 is an electric circuit diagram of a conventional high-frequency heating device, Fig. 2 is a block diagram of the main body of the high-frequency heating device showing an embodiment of the present invention, and Fig. 3 is a block diagram of the high-frequency heating device showing an embodiment of the present invention. The electric circuit diagram, FIG. 4 is an external perspective view showing the humidity sensor. 1... Outlet, 2... High voltage) lance, 3... High voltage circuit, 4... Low voltage transformer A111... Humidity sensor, 16... ...High frequency heating device. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
figure? 3 Figure 2 Figure 3 “--1”-27 I 1 ・1--□□□Go]□□
□□- Akebono 1! I ///jll,' 11■IL- 1\ Ma□--←--□- r l L-11111111----K1 23 6.1 Child - 11 124 l l2 l S l-1li 111111
Hi 11-1 + 11 II V6s, 1 1 Jishiri -" I, V Go -" 1 Chung 9 Ibu Fig. 4 - 13ρ

Claims (1)

[Claims] A heating chamber that stores an object to be heated, a high frequency oscillator that supplies high frequency waves to the heating chamber, a fan that cools the high frequency oscillator, and a sensor that detects information such as steam generated from the object to be heated by heating. and a heater that heats and cleans dirt adhering to the sensor, a guard ring section that is set between the sensor and the heater, a gate trigger element that turns on and off the heater, and a control section that controls them. an electronic control circuit device, one end of the heater is connected to the reference potential of the control section and the guard ring section, the other terminal is connected to the gate trigger element, and a voltage phase applied to the heater is connected. and a high-frequency heating device configured such that the voltages applied to the control section are in the same phase.