JPS5951817A - Electric cooker - 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-1 relates to the configuration of a control circuit for an electric cooker used in a general household, especially an electric cooker equipped with a control circuit having a changeover switch and the like. be.

Conventional configuration and its problems Conventionally, in this +H1 electric jar rice cooker, a switch 10 that responds to the thermostat that detects the completion of rice cooking is connected to the antibacterial circuit 9 having a microcomputer, and this signal (
・The microcontroller was used to distinguish between rice cooking and warming operations. However, this configuration often requires a separate switch for the human input signal, and also requires a separate operating circuit because the relay 7 is connected in series to the twin heater 4 and the power is suppressed. Because of the large number of cases, it had the disadvantage of low reliability.

For example, if the relay contacts are welded, the main heater will become continuously energized, leading to the melting of the crystal heat.

Purpose of the Invention The present invention IT□V solves such problems.
The present invention provides an electric cooking device having an electric circuit configured to face a wall 1'1.

Structure of the Invention The present invention (a σl-1 electric heating element, a switch Jt connected to the electric heating element in the inner row, and driving an active element r from one contact of the switch via a dynia 1-1, 11J (carving 1
In one circuit, a means for performing a glue change operation and a means for controlling an electric current (inner row in a heat recording body),
The reliability is increased by +1- as a configuration in which a plurality of 9 pieces are installed.
? Let me explain about X.

Reference numeral 17 denotes a switch, and one contact 17a is a relatively large contact in order to interrupt the current. Further, since the contact 17b is connected to the active element via the diode 2o, the current is small and the contact is gold-plated.

The relay 18 is an element that opens and closes in response to a drive signal from the control circuit 23 for power control, and connects the main heater 14 and
The switches 17 are connected in series, so that even if the relay contact is welded, the switch 17 will close the rice cooking container 21.
When the temperature of the heater rises, the sensor mostat 22 operates to shut off the main heater and open the main heater, improving reliability.

FIG. 3 shows the circuit of FIG. 2 in more detail.

A contact 29b of the switch 29 is connected to the base of an active element transistor 46 via a resistor 48 and a diode 47. Since the current flowing through the contact 29b is a half wave, a time constant is provided by the capacitor 49, and the output of the transistor 46 becomes a direct current.

The output of the transistor 46 causes the voltage comparator 40 and
The operating temperature of the temperature control circuit including the thermistor 44 and the like can be changed by turning the transistor 46 ON and OFF.

If contact 29a is connected, rice cooking operation is performed,
When the contact 29c is connected, a heat retention operation is performed.

When the contact 29a is connected and rice cooking starts, the temperature control circuit (block B in FIG. 3) and timer circuit operate to maintain the temperature at a constant temperature for a certain period of time.

On the other hand, when rice cooking is finished, the contact 29b is switched, and a diode 47 and a resistor 48 are connected to the base of the transistor 46.
Since the capacitor 49 ensures a time constant, the output of the transistor 46 is converted to a DC signal, and a half-wave current flows.
The control temperature of block A is changed to the control temperature for keeping warm, and the operation of timer circuit block B is prohibited.

Also, the output of the transistor 46 causes the transistor 39 to
is turned on, the relay drive transistor 37 is held off, and the relay is placed on the 28a side.The configuration of the heater 9 is a configuration for a heat-retaining operation in which the electric heating elements 30, 31, and 27 are connected in series.

Effects of the Invention As is clear from the above embodiments, according to the present invention, reliability can be improved because a plurality of power control means are provided in the main current circuit.

Furthermore, by removing the long signal from the reverse contact of the switch to the control circuit, a highly reliable circuit can be constructed without increasing the number of parts.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of a conventional rice cooker, FIG. 2 is an electric circuit diagram of a jar rice cooker showing an embodiment of the present invention, and FIG. 3 is a specific electric circuit diagram of the same jar rice cooker. 27.30.31... Electric heating element, 29...
··switch.

Claims (1)

[Claims] The electric conditioner 1 has a plurality of electric heating elements and a plurality of power control means, and has at least two or more power control means connected in series to the large current circuit of the electric heating element. ll vessel,.