JPS5949497B2 - heating cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a heating cooker such as a gas oven.
The present invention relates to a programmable control device that controls the setting, storage, and operation of various heating sequence patterns combining heating temperature, heating time, and order.

It has long been understood that cooking appliances that use gas combustion energy as a heat source, such as gas ovens, have advantages in terms of energy efficiency and cooking performance (finishing) compared to cooking appliances that rely on other heat sources. However, there are difficulties in controllability.
Its realization was delayed.

On the other hand, regarding the method of proportionally controlling the gas flow rate so that the temperature inside the oven reaches the target value, and its control means,
An idea has been made to improve cooking performance by controlling an electronic proportional control valve using an electronic control circuit to maintain a constant open temperature.

However, in general, many types of heating cooking involve not only heating at a constant temperature for a certain period of time, but also by sequentially controlling multiple steps by treating a combination of temperature and time as one step. There are many items that can be cooked with good heat.

Furthermore, the cooker itself has a function that allows you to pre-memorize ideal heating sequences for these cooking items and recall them as needed. If you can do this, you will have advantages in terms of cooking quality and energy efficiency, as well as a dramatic expansion of the cooking range, flexible usability, etc.
This new feature makes it possible to realize an ideal heating cooker.

The present invention relates to a control method and specific control means based on the above viewpoints.

The concept of the control method of the present invention will be explained with reference to FIG. 1a.

27 is open, 28 is a gas burner, 28a is a gas flow path, and the gas flow is interrupted by a cock 26.

Further, the cock 26 works in conjunction with the igniter 35 to open the gas flow path and ignite the burner at the same time.

27b is a heat shield plate. 29 is an electronic proportional valve, which has a function of controlling the gas flow rate in proportion to the control signal 31a.

31 is a temperature control circuit, which is located at a corner 27a of the open 27.
The temperature inside the opening is detected by a temperature sensor 30 located inside, and the detected signal is compared with a set target temperature value 32a, and the difference signal is amplified and a control signal 31a is output.

It also outputs a temperature attainment signal 38 to the monitor 32.

The monitor 32 stores the cooking item number, temperature, time, or displays the stored contents according to the operation of the key switch or card reader on the operation surface 33, and also displays the proportional control circuit 3.
Output of code 32a corresponding to the set temperature for 2, during operation, controls or monitors the entire operation and operation of the gas open, such as counting heating time, controlling the heating sequence, and logical control and notification function considering safe operation. It is a circuit.

The control method shown in FIG. 1a makes it possible to control the heating sequence as shown in FIG. 1 and to store the heating pattern.

In Figure 1, ta is the time until the open reaches temperature T3, (tl-ta) is the time to maintain temperature T3, (12-11) is the time to maintain temperature T2, (13
-12) is the time to maintain the temperature T1.

That is, each stage consists of three sequences of reached temperatures and durations.

This one combination is called a stage. FIG. 1 shows that by executing the programmed target control pattern C2 in three stages indicated by solid lines, an actual temperature versus time curve C1 is obtained.

Corresponding to FIG. 1a, T1. T2. The part that detects and controls T3 is 30° 30a 31 31a 29
28, (T3.(tl-ta)), (
T2. (t2tt)).

The combination of (T1.(t3-t2)), setting of the order, and display are performed by the operation unit 33, and the storage and reading of the setting pattern, execution of the setting pattern, and overall sequence control are performed by the monitor 32. Let's do it.

A specific example of each functional block in FIG. 1 will be described below.

FIG. 2 is an example of the operation and display section.

1 is a gas open outer box, 2 is a display tube, and 43 represents the time from 00 to 99 in minutes.

567 represents the temperature in degrees Celsius.

8 represents the stage number.

Reference numeral 9 indicates automatic operation, and reference numeral 10 indicates manual operation. When the card 90 is not inserted into the card reader 16, the manual operation is displayed.

At this time, all of the displays 3 to 8 are lit, and the displays can be changed using the keys described below.

Numeral setting key switches 11, 12, 13, 14, and 15 correspond to 34678, as shown by the arrows, and each time the keys are pressed, the corresponding number 9 is incremented by 1 and displayed.

When the card 90 is inserted into the card reader 16, the card reader built-in switch 91, which is a card insertion detection means,
is closed, and the automatic display 9 is turned on by the monitor 32.

At the same time, the monitor 32 erases the displays 3 to 8, reads the inserted card number, and newly displays the number 34 corresponding to the card number.

Next, when the start switch 24 is pressed, cooking information such as stage, temperature, and time is displayed in 3 to 8 displays, as in the manual mode, to clearly indicate the current settings.

Automatic is a function that automatically cooks food by calling and setting the cooking items stored in the card 90 in advance by assigning numbers to various cooking patterns as shown in Figure 1. , Manually means that after setting the temperature and time for each stage as necessary,
This function allows you to cook according to that sequence.

17 18 19 20 21 22 2 as necessary
By operating the keys in the homemade area No. 3, the manual cooking pattern can be stored, read out, and set.

The number of manual cooking types that can be stored at this time is five.

Numeral 25 is a key used for commands such as canceling set values during setting, erasing stored values, and stopping operation during operation.

26a is a knob for operating the cock 26 and the ignition switch 35.

In the stop position, the cock is closed; in the ignition position, the cock opens and simultaneously ignites the burner.

FIG. 3 shows a specific embodiment of the monitor 32. As shown in FIG.

The core of the monitor 32 is the LSI chip 32b, and in this example, it uses a stored program method.
It uses a microcomputer 7 computer, which is a general-purpose chip from Program.

So. Sl, Ao, A□, A2. A3 is the input terminal, c
o, C1゜C2, C3, C4, C5, C6, C7, C8
, C9, C10゜cti, Do, DI, D
2, D3, D4, D5, D6 are output terminals, VDD and VSS are power supply terminals, RE-8ET
is a chip initialize terminal, and O8C is a terminal for basic clock oscillation.

Input terminal A.

, AI, and A2 are used to input signals from the key switch group 37 in the operation section 33.

A3 inputs the temperature attainment signal 38. co. c,,C2
, C3, c, , c, , C6 are output terminals for directly driving each numerical digit of the display tube 2, and Co-C6
Each digit is driven by scanning at a certain period, and it is also used as a signal to select keyboard switches group by group.

Do%D6 selects and directly drives the display segment of the display tube 2 according to the number to be displayed.

The resistor group 4748 is a resistor for supplying a negative bias voltage to the terminal of the display tube when the output terminal is OFF, and the negative bias voltage is determined by the constant voltage diode 39.

52 is a cathode of the display tube and also a filament.

The filament is heated by a filament power transformer 46.

The terminal S1 is a terminal for inputting the commercial power frequency to the microcomputer 32b, and is connected to a transistor 45 and a resistor 45.
A 45b shapes the waveform and inputs the signal.

32b counts the commercial power frequency, for example 60 Hz, as the reference time of the timer.

Terminal S. In order to select the operation sequence of the microcomputer in accordance with the commercial power frequency that differs depending on the region, S
.

This is a terminal to which the potential of the terminal, that is, the logic level, is changed and input.

Terminal c8. C9, CIO, C1l are temperature control circuit 3
1, the target temperature value is encoded and output.

Since a 4-bit code can be output by 08 to C1□, temperature setting of 24=16 levels is possible.

53 is a 4-bit decoder, which converts the 4-bit code into 16
decode it into a signal and output it.

eoel, . . . C15 is an output terminal of the decoder 53.

Terminal C7 turns on the power to the temperature control circuit 31. / Outputs a signal to connect resistor 41 and transformer FF The register 40 activates the relay 42.

The contact 42a of the relay 42 turns the power supply circuit of the temperature control circuit 31 ON10FF (see FIG. 9).

FIG. 4 is a detailed diagram of the key switch group 37.

Ko, 1. --------, 3 is 11 in Figure 2
, 12°...corresponds to 25 key switches, K
14 corresponds to the card reader switch 91.

The input signal to the microcomputer 32b is Co-0
When the scanning pulse E S-E output from Ao, A1 . It is taken in as a key switch signal from the A2 terminal.

For example, if the K8 key is pressed when there is an Eco pulse, the Eol pulse value is input to Ao.

FIG. 5 is a detailed diagram of the fluorescent display tube drive circuit.

4950 is an output driving transistor of a microcomputer, and in the case of a P-channel M'OS process, it has an output terminal of an open drain structure.

The drain terminals of the output transistors Do to D6 are connected to the anode (segment) of the fluorescent display tube 2 and partially connected to each other through a resistor 47.

The drain terminals of the output transistors Co to C6 are connected to the grid (digit designation) of the fluorescent display tube 2, and similarly connected to -V through a resistor 48.

As is well known, in a fluorescent display tube, when a voltage is applied to both the anode and the grid to the cathode, that segment emits fluorescence, so the output transistor connected to Do-D6 becomes conductive, and the output transistors C8 to C6 become conductive. When a suitable transistor is turned on, Vss-VrV] is applied between the anode and the cathode and between the grid and the cathode, and a predetermined segment emits light.

On the other hand, for example, if the output transistors 49 and 50 are cut off, each anode and grid are biased at -Ea (V) with respect to the cathode through resistors 47 and 48, and light emission is stopped.

The timing of the above display follows the procedure of a control program stored in the microcomputer.

FIG. 6 shows the representation format of numbers by segments of the display tube and the corresponding figures.

-D6 output code list.

In FIG. 6, 140/4 indicates that the output transistor is in a cut-off state, and 1" indicates that the output transistor is in a conductive state.

FIG. 7a is a representative example of the architecture of the microcomputer chip used in the present invention.

The ROM is a fixed storage unit in which control procedures related to gas open display and operation are programmed and stored in the form of instruction codes.

In this example, an i8-bit instruction code can be stored with a maximum of 2048 steps.

IR is an instruction register that temporarily stores instruction codes read from the ROM.

The PC is a program counter that specifies and updates the address of the instruction code in the ROM.

Since it is necessary to specify addresses for a maximum of 2048 (=211) steps, 11 bits are required.

5TACK is a register that holds the return address when a subroutine is called.

MPX53 uses the address held in the stack and the BR
(Branch) This is a multiplexer that selects the specified address when the instruction is executed.

1N5T-DEC is an instruction decoder and decodes the contents of the instruction register.

RAM is a writable and readable data memory, and can be stored and read in units of 4 bits.

The storage capacity is 4 bits x 128 steps.

Addressing of 128 steps is possible with 7 bits, and the RAM address register uses 3 bits of
There is a 4-bit X register.

The contents of the X register are decoded by the DEC 55 and the output terminals of co-07 are individually specified.

The ALU is an arithmetic logic unit and performs various processing decisions.

Two sets of 4-bit data are input to the ALU according to the command, and the processing results are sent to the ACC (
accumulator), CF ZF (flag), X register, or RAM.

TEMP is a 4-bit register used for temporary storage.

PS is a program status and is a 1-bit register that is set or reset by an instruction.

CF is carry fluff, and as a result of processing in ALU,
Set when a carry occurs from the highest pitch.

ZF is a zero flag, and is set when the result of processing by the ALU is zero.

C indicates a comparison circuit.

C and G are clock generators, circuits that generate basic frequency signals for microcomputer operation, CNT
SEQ is a control sequence circuit that controls the internal operating procedures of the microcomputer.

The numbers appended to the signal lines in FIG. 7a represent the number of bits of the signal lines.

The microcomputer architecture described above is controlled according to instruction codes stored in its own ROM, and as a result controls key switches, display tubes, and temperature control circuits connected to each input/output terminal, and also controls various gases. Stores and reads heating sequence patterns for automatic cooking.

FIG. 7 shows part of the structure of an instruction code of a microcomputer based on the architecture of FIG. 1a.

Functions such as inputting data from key switches, displaying numerical values, outputting target temperature codes, storing and reading various cooking patterns, and controlling cooking sequences are as follows.
All are programmed with the combination of instruction codes shown in FIG. 7 and stored in the ROM in advance.

FIG. 8 shows the electromagnetic proportional control valve 29.

Reference numeral 70 denotes an outer body, which has a gas manifold lower 1 and a gas converter lower 2 on both sides, and a valve seat 73 is attached with a screw 83 via a gasket 84 in a passage leading from the inlet lower 1 to the converter lower 2.

14 is an intermediate opening. 75 is a cylindrical bobbin around which a coil 76 is wound, and magnetic washers 77 are abutted on both ends to form an outer body 70.
Together, they constitute a magnetic circuit.

A magnetic plunger 78 is housed in the hollow cylinder of the bobbin 75, and has a valve 79 at one end that corresponds to the valve seat 73 and opens and closes the intermediate lower 4, and a non-magnetic member 80 at the other end.

81 is integrally fixed to the outer body with a leaf spring, and the other end is rotatably attached to the plunger 1880.

Next, this raising operation will be explained.

When no current flows through the coil 16, the leaf spring 81 always presses the valve 79 against the valve seat 73, and at the same time presses the plunger 7.
8 is prevented from swinging left and right and coming into contact with the bobbin 75.

When current flows through the coil 76, an electromagnetic force is generated and a force that pulls the plunger 78 upward is exerted. This force acts on the leaf spring 81.
When the force is overcome, the plunger 78 is pulled up and the valve 7
9 leaves the valve seat 73 and comes to rest at a place where the electromagnetic force and the force of the leaf spring 81 are balanced.

The degree of opening of the valve 79 is proportional to the current flowing through the coil 76.

FIG. 9 shows an embodiment of a temperature control circuit using a proportional valve.

The temperature sensor 30 is a temperature sensing element such as a positive temperature coefficient thermistor, and is linearly corrected by a resistor 8586 and connected as an input resistor of the operational amplifier 89.

A reference voltage corresponding to the target temperature value set in FIG. 3 is applied to the positive input terminal of the operational amplifier 89.

The feedback resistance of the operational amplifier is Rf, the resistance of the temperature sensitive resistance element 30 is R30, and the resistors 85.86 are R85 and R8, respectively.
6, the output voltage E of the operational amplifier.

here It is.

According to equation (1), if R3o is a positive characteristic thermistor, as the temperature rises, R(T) increases and the absolute value of the first term becomes smaller, so Eo increases in the positive direction.

The current in the coil 16 is reduced accordingly, reducing the amount of combustion and lowering the temperature of the oven.

If the temperature drops too much, the temperature is raised by the reverse operation.

88 is a diode for absorbing back electromotive force of the coil 16.

Here, R8(T) is a voltage corresponding to the set temperature,
In FIG. 3, RO-ats is selected by turning the transistor 56 ON10FF in response to the code output from the output terminals 08 to C1l of the microcomputer 32b.

As a result, a voltage Es (T) is generated, which is the constant voltage +Vcc divided by R6-R15 and RS, and the temperature control circuit 3
1 reference voltage.

Note that the contact 42a is connected to C7 of the microcomputer 32b.
These are the contacts of the relay 42 controlled by the output.

FIG. 10 shows the rise characteristic, which is part of the control characteristic.

The vertical axis T is the oven temperature, and the horizontal axis t is the elapsed time.

Set the temperature to T. When the oven is closed and burned from time O, the oven temperature rises over time as shown in the curve, and after showing some overshoot characteristics, the set temperature T is reached.

calm down. It can be said that this level of characteristics is closest to the ideal.

As described above, by using the high-precision temperature control circuit and the characteristics of the proportional valve, high-quality heating cooking can be achieved by performing stepwise control as shown in the example of FIG.

□ As is clear from the above explanation, the advantages of the present invention are (
1) Heating control that combines multiple oven temperatures and durations can be specified and executed with a simple key switch operation.

(2) By using the card input that stores the heating cooking pattern, the user does not need to set the original numerical value in the cooking block.

(3) Since the set temperature and time can be displayed numerically for each step, monitoring during cooking is easy.

(4) The configuration is such that a card insertion signal can be obtained)
Therefore, just by inserting the card, the cooking mode automatically switches to automatic cooking, and since the automatic display is performed, no extra key operations are required, making it easy to use.

(5) Since the card number is displayed when the card is inserted, confirmation is easy and misuse can be prevented.

Examples include.

[Brief explanation of drawings]

FIG. 1a is a diagram showing the principle of the cooking device of the present invention, and FIG. 1 is a diagram showing an example of a heating cooking pattern controlled by the present invention.
FIG. 2 is a front view showing an example of the gas open operation unit realized by the present invention, FIG. 3 is a diagram showing an example of the monitor/controller circuit, FIG. 4 is a diagram showing an example of the key switch input circuit, and FIG. FIG. 5 is a diagram showing an example of a fluorescent display circuit driving circuit, FIG. 6 is a diagram showing the correspondence between segments and codes of the numeric display section, and FIG. 7a is a configuration diagram of a microcomputer.
Figure 7 is a diagram showing an example of the configuration of an instruction code, Figure 8 is a sectional view showing the structure of an electronic gas proportional valve, Figure 9 is a diagram showing an example of a proportional control circuit, and Figure 10 is a diagram showing temperature and time. It is a control characteristic diagram in the relationship. 2...Display tube, 11-1517-25...
...Key switch, 16...Card reader,
29...Electronic proportional valve, 30...Temperature sensor, 31...Temperature control circuit, 32...
. . . Monitoring means, 32b . . . Microcomputer, 90 . . . Card, 91 . . . Card insertion detection means (switch).

Claims (1)

[Claims] 1. A keyboard comprising at least a switch for setting numbers, a switch for setting cooking functions, a switch for controlling cooking operations, and a switch for starting cooking; means for displaying in accordance with the function; means for detecting the temperature of the oven; temperature control means for controlling the amount of heat supplied to keep the temperature of the oven constant; and a switching signal from the keyboard that can be input and stored or read. the keyboard, the temperature or heating amount control means, the display means, and the temperature detection means. a card in which cooking functions are stored in advance; a card reader for reading cooking information from the card; and a card insertion detection means for detecting the insertion signal. This heating cooker is configured so that the control function automatically switches from manual setting cooking to automatic setting cooking when 2. The cooking device according to claim 1, wherein the monitor means has a function of reading the card number and outputting the number to the display means when the card is inserted. 3. The heating cooker according to claim 1, wherein the display means has an automatic status display function to notify that the setting has been switched to automatic setting based on a signal from the card insertion detection means when the card is inserted. 4. The monitor means displays the card number on the display means when the card is inserted and at the same time turns off all other displays, and when the start switch is pressed, displays cooking information such as temperature and time necessary to know the cooking status. The heating cooker according to claim 1, which has an automatic cooking information display function.