JPH074309B2 - Cooker with clock - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooker with a clock having a clock function, such as a jar rice cooker, a coffee brewer, and a microwave oven, which are used by being connected to an AC power source.

2. Description of the Related Art A conventional cooker with a clock of this type has a circuit configuration as shown in FIG. FIG. 3 is a circuit diagram of a conventional jar rice cooker with a clock, which includes a microcomputer 1 and peripheral circuits. The microcomputer 1 shown here is a so-called one-chip microcomputer including a CPU, a ROM, a RAM, an input / output port and the like. Reference numeral 2 denotes an oscillation circuit including a ceramic oscillator 3 and an inverter 4, and the oscillation circuit 2 determines a processor cycle in which a program of the microcomputer 1 is operated. Reference numeral 5 denotes a timepiece oscillation circuit including a crystal oscillator 6 and an inverter 7. The timepiece oscillation circuit 5 is input to the microcomputer 1 and determines the basic period of time measurement. A liquid crystal display device 8 displays the time and the like by a signal from the output port of the microcomputer 1. Reference numeral 9 is a setting switch for setting the time, 10 is a rice cooking switch for starting rice cooking, and this rice cooking switch 10 is input to the microcomputer 1 so as to determine whether or not the rice cooking switch 10 has been pressed. Reference numeral 11 denotes an AC power supply. A series circuit of a heater 12 and a relay contact 13 is connected to the AC power supply 11, and a signal from an output port of the microcomputer 1 is passed through a transistor 14 to a relay coil 15 so that a current flows. It is configured to open and close the relay contact 13. Reference numeral 16 is a zero volt detecting means for detecting zero volt of the AC power supply 11, which is full-wave rectified by the transformer 17 and the diode bridge 18 and is divided by the resistors 19 and 20, and the divided voltage is inputted to the base of the transistor 21. The zero voltage of the AC power supply 11 is detected. 22 is a microcomputer 1
It is a DC power supply that drives the circuit such as.

With the above configuration, the time for cooking rice is set by the setting switch 9, and when the rice cooking switch 10 is pressed, the relay contact 13 is turned on at the set time, and the heater 12 is energized. The signal of the zero volt detecting means 16 is used to set the timing of turning on / off the relay contact 13 to near zero volt.

Problems to be Solved by the Invention In such a conventional configuration, in order to improve the accuracy of the timepiece, the crystal oscillator 6 is required, and since a high-accuracy one is also required, it is expensive and However, there was a problem that the number of parts increased.

The present invention solves such a problem, and improves the accuracy of time measurement by detecting variations in ceramic oscillators and the like and automatically correcting them with a simple configuration, and at the same time, it is an inexpensive component. It is an object of the present invention to provide a cooker with a clock, which is configured by and can reduce the number of parts.

Means for Solving the Problems In order to solve the above problems, the cooker with a clock of the present invention is
Zero volt detection means for detecting zero volt of the AC power source, an oscillator made of ceramic, etc., counting means for counting the output cycle of the zero volt detection means by the output of the oscillator, and the count value of the counting means. Storing means, an AC power supply detecting means for detecting whether or not it is connected to an AC power supply, and an output of the zero volt detecting means when connected to an AC power supply by the output of this AC power supply detecting means. It is provided with clock counting means for counting and counting the oscillator when it is not connected to an AC power source, and correcting and counting with the measured value of the storage means.

Operation According to the above configuration, while connected to the AC power supply, the number of zero volts of the AC power supply is counted to count the time, and at this time, the variation of the oscillator is counted to determine the correction value. , While it is not connected to the AC power supply, the time can be counted based on the correction value that corrects the variation of the oscillator, so even if the variation of the oscillator is large, the stable cycle of the AC power supply can be counted. In addition, the accuracy of time measurement is improved, and stable time measurement can be performed. Further, since a highly accurate crystal oscillator or the like is not required, it can be obtained at low cost.

Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, the same parts as those in FIG. 3 shown in the conventional example are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 1 is a circuit diagram of a jar rice cooker with a watch according to an embodiment of the present invention. Compared with FIG. 3 shown in the conventional example, the watch oscillator circuit 5 including the crystal oscillator 6 is eliminated. It is configured.

Next, the operation of the timepiece measuring device configured as described above will be described.

FIG. 2 shows a flow chart of a program stored in the ROM of the microcomputer 1. The procedure of the program shown in this flow chart will be described.
First, in step 1, it is determined whether or not it is connected to the AC power supply 11, and if it is connected to the AC power supply 11, the process proceeds to step 2. In step 2, determine whether it is 50Hz, and
If it is Hz, F = 100 is set in step 3, and if it is not 50 Hz, F = 120 is set in step 4, and the process proceeds to step 5. In step 5, it is determined whether the AC power supply 11 is zero volt. If the AC power supply 11 is not zero volt, the process proceeds to step 6, in which it is determined whether the counter exceeds 1 / F second. If the counter is 1 / F seconds or less in step 6, proceed to step 5, and if the counter is 1 / F seconds or less in step 6, proceed to step 1.

If the AC power supply 11 becomes 0 volt in step 5, the process proceeds to step 7, T = T + 1 is set, and the process proceeds to step 8 to store the value of the counter in T ₁ . Further, in step 9, the counter value is set to zero and the process proceeds to step 10. If T <F here, the process proceeds to step 1. In step 10, if T ≧ F, the process proceeds to step 11, increments the time count by 1 second, and then proceeds to step 1.

When it is determined in step 1 that the AC power supply 11 is not connected, the process proceeds to step 12, and in step 12, the counter is T ₁
If this is the case, the time count is incremented by 1 second in step 13, and then the process proceeds to step 1. If the counter is less than or equal to T _{1 in} step 12, proceed directly to step 1.

EFFECTS OF THE INVENTION As described above, according to the present invention, while connected to an AC power supply, the number of zero volts of the AC power supply is counted and time is counted, and further, the variation of the oscillator is counted at this time. Determine the correction value in advance, and while it is not connected to the AC power supply,
Since it is possible to count time based on the correction value that corrects the variation of the oscillator, the stable cycle of the AC power source is counted even if the variation of the oscillator is large, so the accuracy of time measurement is improved, and moreover, Since stable time measurement can be performed and a highly accurate crystal oscillator or the like is not required, it can be obtained at low cost.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a jar rice cooker with a clock showing an embodiment of the present invention, FIG. 2 is a flow chart showing an example of a program of the jar rice cooker with a clock, and FIG. 3 is a circuit of a conventional jar rice cooker. It is a figure. 1 ... Microcomputer, 2 ... Oscillation circuit, 3 ...
Ceramic oscillator, 8 ... Liquid crystal display device, 11 ... AC power supply, 16 ... Zero volt detection means.

Claims (1)

[Claims] 1. A zero volt detecting means for detecting zero volt of an alternating current power source, an oscillator made of ceramic or the like, and a counting means for counting the output cycle of the zero volt detecting means by the output of the oscillator. Storage means for storing the count value of the counting means, AC power supply detection means for detecting whether or not it is connected to an AC power supply, and zero volts when connected to an AC power supply by the output of this AC power supply detection means. A cooker with a clock equipped with a time counting means for counting the output of the detecting means, counting the oscillator when not connected to an AC power source, and correcting with the count value of the storing means.