JPS58149715A - Rice 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] [Technical Field of the Invention] The present invention relates to a rice cooker equipped with a control circuit that uses a rice cooking signal to form a heater energization circuit to perform rice cooking, and particularly a rice cooker that uses a soft touch automatic return type that uses the rice cooking signal to perform rice cooking. The present invention relates to a rice cooker in which rice cooking is activated by a rice cooking operation switch.

(Technical Background of the Invention and Problems Thereof) Conventionally, for example, in a heat retention type rice cooker, a rice cooking signal causes a rice cooking operation to be performed and then a warming operation to be performed, a warming signal causes a warming operation to be performed, and a stop signal causes the above-mentioned heating operation to be performed. A control circuit for stopping the rice cooking operation or the warming operation is provided, and the rice cooking signal is also controlled.

By configuring the heat retention signal and stop signal to be generated by soft-touch automatic return type operation switches for rice cooking, heat retention, and stop, respectively, it is possible to achieve excellent operability and improve the degree of freedom in design. In such a rice cooker, each operation switch is of an automatic reset type, so the output status of the rice cooking signal, keep-warm signal, etc. corresponding to these operations is electrically maintained. That's what I do. However, with this configuration, in the event of a momentary power outage, the holding of the output state is inadvertently canceled, so that after the power is restored, the rice cooking or warming operation is stopped midway and left unnoticed. There is a possibility.

(Object of the Invention) The present invention was made in view of the above circumstances, and its purpose is to provide excellent operability and improve the degree of freedom in design, as well as to prevent rice cooking from occurring due to momentary power outages, etc. To provide a rice cooker which exhibits effects such as no fear of being stopped midway through preparation.

[Summary of the invention]

The present invention provides a rice cooker in which rice is cooked by forming a heater energization circuit in response to a rice cooking signal generated by a rice cooking operation switch of a soft-touch automatic return type.
The present invention is characterized in that the state in which the heater energizing circuit is formed is mechanically maintained when the rice cooking signal is output.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

1 is a 100-volt single-phase AC power source, and between its terminals are an output switch 2a of a drive circuit 2, which will be described later, and an electric heater for cooking rice 3 that heats the rice cooker. A series circuit of a rice cooking detection switch 4, which turns off when rice cooking is completed by sensing the temperature of the pot, and an output switch 5a of a drive circuit 5, which will be described later, is connected, and is connected in parallel with the series circuit of the rice cooking detection switch 4 and output switch 5a. A series circuit including a heat-retaining electric heater 6 that heats the pot and a thermal switch 7 that senses the temperature of the pot and turns it on and off is connected to the pot. In this case, the on-temperature of the rice cooking detection switch 4 is set slightly lower than the on-off temperature of the thermal switch 7. Reference numerals 8, 9 and 10 are respectively a push button switch for rice cooking which is a rice cooking operation switch, a push button switch for keeping warm which is an operation switch for keeping warm, and a push button switch for stopping which is an operation switch for stopping. , the negative terminal is connected to the positive terminal 11 of a grounded DC power supply, for example +VC volts, and each terminal is connected to the line L1 . Connected to L2 and L3. In this case, each of the push button switches 8, 9 and 10 is of a soft-touch automatic return type with a movable contact piece made of conductive rubber,
When the conductive rubber is pressed down lightly, it is turned on while the conductive rubber is pressed down. Therefore, this soft-touch type switch has an extremely simple structure, and is smaller and lighter than the known mechanical push button switch. 12 and 1
3 is a relay called a so-called keep relay, and these have electromagnets 12a, i3a, 12b, and 13b for operation and return, respectively, and when the operation electromagnets 12a and 13a are energized, they turn on contacts 12C913C, respectively. At the same time, even if the excitation is stopped thereafter, the on state is mechanically maintained, and when the return electromagnets 12b and 13b are energized, the contacts 12C and 13C are turned off, and the excitation is then stopped. This configuration maintains the above-mentioned off state even if the

In such relays 12 and 13, the operating electromagnet 1
2a and 13a are connected between the line L1 and the ground, and between the line L2 and the ground, respectively, and the return electromagnets 12b',
13b is connected to the line L3 and the line L3. Now, 14 is a control circuit, which will be described below.

That is, 15 has one of its pair of input terminals connected to the line L.
3 and the other is connected to the positive terminal 11 via the line L4 and the contact 130, and its output terminal is connected to the reset input terminal R of the R-8 type flip-flop circuit 16. There is. 17 is an OR circuit in which one of the pair of strain input terminals is connected to the input L4, and the other is connected to the positive terminal 11 via the line L5 and the contact 12C, and its output terminal is of the R-8 type. It is connected to the set input terminal S of the flip-flop circuit 18. This flip-flop circuit 18 has its reset input terminal R
is connected to the line L3, and the set output terminal Q is connected to the input terminal of the drive circuit 2, and the set input terminal S of the flip-flop circuit 16 is connected to the line L5. At the same time, a set output terminal Q is connected to an input terminal of the drive circuit 5.

In this case, the drive circuits 2 and 5 each have an output switch 2a
and 5a, and when a high-level signal is applied to each input terminal, the relays are energized to turn on the output switches 2a and 5a, respectively.

Next, the operation of this embodiment will be explained.

First, when the rice cooking push button switch 8 is pressed down, the rice cooking push button switch 8- is turned on and a rice cooking signal 3a of +z and VC volts is generated on the line L1.
This rice cooking signal Sa causes the electromagnet 1 for operating the relay 12 to
2a is excited, the contact 12c is turned on, and this on state is mechanically maintained even after the push button switch 8 for rice cooking is released. Then, in response to the turning on of the contact 12C, +Vc volts, that is, a rice cooking signal S'a, which is a high level signal, is outputted to the line L5, and this is applied to the set input terminal S of the flip-flop circuit 16 and also to the OR circuit 17. The signal is applied to the set input terminal S of the flip-flop circuit 18 through the flip-flop circuit 16, 18, and the flip-flop circuits 16 and 18 enter the set state, and the set output signal of each set output terminal Q thereof becomes high level.

Then, the high-level set output signals of the flip-flop circuits 18 and 16 are applied to the drive circuits 2 and 5, respectively, so that the drive circuits 2 and 5 turn on the output switches 2a and 5a, respectively. As a result, the rice cooking electric heater 3 is energized via the output switch 2a, the rice cooking detection switch 4, and the output switch 5a to generate heat, thereby starting the rice cooking operation. In this case, the series circuit of the warming electric heater 6 and the thermal switch 7 is short-circuited by the rice cooking detection switch 4 and the output switch 5a, so that the warming electric heater 6 is not energized. after that,
When the rice cooking in the rice cooker is finished, the temperature of the rice cooker will rise rapidly, so the rice cooking detection switch 4 will sense this and turn off. They are connected in series and are energized when the thermal switch 7 is turned on, thereby starting the heat retention operation. Thereafter, both the electric heaters 3 are turned on and off by the thermal switch 7 that detects the concentration in the pot.
．． The series circuit of No. 6 is now controlled to be powered off, and the heat retention operation is continued.

In the above case, when the stop push button switch 10 is pressed, the stop push button switch 10 is turned on and +V is turned on.
A stop signal SC, which is a c-volt, that is, a high-level signal, is generated on the line L3, and this is applied to the reset input terminal R of the flip-flop circuit 16 via the OR circuit 15, and directly to the reset input terminal of the flip-flop circuit 18. Then, the flip-flop circuits 16 and 18 are inverted to the reset state, and the set output signals at the respective set output terminals Q are set to low level. As a result, the drive circuits 2 and 5 are connected to the output switch 2.
a and 5a are turned off, and therefore the rice cooking operation or warming operation as described above is stopped. At the same time, the return electromagnet 1211.13b of the relay 12.13 is excited by the stop signal SC, so the contact 12
C213c is now turned off.

On the other hand, when the heat retention push button switch 9 is pressed,
The heat retention push button switch 9 is turned on and a heat retention signal sb of 10 VC volts is generated on the line L2, and this heat retention signal sb excites the operating electromagnet 13a of the relay 13, turning on the contact 13c. The on state is mechanically maintained even after the pressing operation of the heat retention push button switch 9 is released. Then, in response to the turning on of the contact 13c, +VC volts, that is, a high-level signal S', is output to the line L4, and this is sent to the reset input terminal R of the flip-flop circuit 16 via the OR circuit 15.
It is also applied to the set input terminal S of the flip-flop circuit 18 via the OR circuit 17, so that the flip-flop circuit 18 is put into the set state and the flip-flop circuit 16 is put into the reset state. Therefore, the drive circuit 2 turns on the output switch 2a, and the drive circuit 5 turns off the output switch 5a, and the electric heater 3 for cooking rice and the electric heater 6 for keeping warm are connected in series and energized, and a keeping-warm operation is performed. It will be done.

In the above embodiment, the operation switches are soft-touch automatic return type push button switches 8 to 1 using conductive rubber.
0 is used, but instead, a soft-touch automatic return type that utilizes changes in capacitance due to the touch of the user's finger may be used.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings; for example, the control circuit may be configured by combining a plurality of relays, or may be configured by a microcomputer, etc. Of course, modifications may be made as appropriate without departing from the spirit of the invention.

〔Effect of the invention〕

As explained above, the present invention uses a soft-touch automatic return type as the rice cooking operation switch, so the operation switch is lightweight and has excellent operability. Since the structure is simple, compact, and lightweight, there are no significant restrictions on the mounting position or mounting space, and an excellent effect can be achieved in that the degree of freedom in design can be improved. Moreover, when a rice cooking signal is generated by the operation switch and a heater energization circuit for rice cooking is formed, the configuration is such that the heater energization circuit formation state is mechanically maintained.
Even if there is a momentary power outage during the rice cooking operation, there is no possibility that the rice cooking operation will be stopped inadvertently.

[Brief explanation of the drawing]

The figure is an electrical configuration diagram showing one embodiment of the present invention.
is a drive circuit, 3 is an electric heater for rice cooking, 4 is a rice cooking detection switch, 5 is a drive circuit, 6 is an electric heater for keeping warm, 8 is a push button switch for rice cooking (operation switch for rice cooking), 12.13 is a relay, 14 is a It is a control circuit. Applicant Tokyo Shibaura Electric Co., Ltd.

Claims (1)

[Claims] 1. In the rice-cooking device, which is equipped with a soft-touch automatic return type rice-cooking operation switch that generates a rice-cooking signal, and a control circuit that uses the rice-cooking signal to form a heater energization circuit to perform rice cooking, the rice-cooking signal is output. A rice cooker characterized in that a relay is provided for mechanically maintaining the heater energization circuit formation state by the control circuit.