JPH01163692A - Weather information display device - Google Patents

Abstract

PURPOSE:To reduce the size of the title weather information display device and to accurately display a weather state by detecting variation in atmospheric pressure as variation in the output of an absolute pressure sensor and turning on and off a display element according to the output variation. CONSTITUTION:An interruption signal generating circuit 71 charges a capacitor 72 when a transistor (TR) 20 turns on, and the capacitor 73 is discharged through a resistance 74 after the TR 20 turns off to send an interruption signal to a microcomputer 91 through a CMOS inverter 75. The microcomputer 91 enters a stand-by state after the TR 20 turns off, and becomes active again by receiving the interruption signal. Further, a signal from the absolute pressure sensor 41 is inputted 16 times at specific intervals of time, e.g. 5min to find the mean value. If there is variation, the stored value is updated to a new mean value and one of LED1-LED4 is lighted in correspondence to the variation to display the weather state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a weather/sunny information display device that displays weather conditions based on changes in atmospheric pressure, such as clear skies, rain then clear skies, sunny then rain, and rainy conditions.

[Conventional technology]

It is known that weather conditions can be predicted to some extent by knowing changes in atmospheric pressure.

Generally, air flows from areas of high pressure to areas of low pressure. When there is low pressure, the air is lifted up into the sky, expands, cools, becomes fog and clouds, and eventually falls as rain, resulting in more rain. When there is high pressure, the air conversely comes down.
Temperatures rise at a rate of about 1°C per 100m, which causes clouds to evaporate and clear skies to often occur. From this principle,
By measuring atmospheric pressure, you can predict the weather to some extent.

Among the conventional methods, Japanese Patent Laid-Open No. 48-94455 is known as a method for predicting the weather from changes in atmospheric pressure. This is done by arranging a main shaft rotated by a motor on the same axis as the center of rotation of the needle of an aneroid barometer, and fixing a pair of contacts in the direction of rotation of the needle with the needle sandwiched between the main shaft. When the needle contacts one of the contacts due to the rotation of the needle due to changes in atmospheric pressure, the main shaft (or motor) is rotated in the direction in which one contact moves away from the needle, and the rotation of the main shaft causes the other pointer to move. While the pointer is rotated by a large power such as a motor, the direction of rotation of the main shaft is detected, and depending on the direction of rotation, a pilot lamp indicates that the atmospheric pressure is rising.A pilot lamp does not indicate that the direction of atmospheric pressure fluctuation has been reversed. , one of the pilot lamps indicating the atmospheric pressure 14 is turned on.

[Problem that the invention seeks to solve]

The above-mentioned conventional barometer requires a motor to rotate the main shaft so that the main shaft follows the rotation of the needle of the aneroid barometer, which has the disadvantage of increasing the size of the device. Therefore, it is extremely inconvenient to carry it around while traveling to predict the weather at the destination.

Furthermore, since the conventional system simply indicates the direction of atmospheric pressure fluctuation, it is difficult to immediately predict the weather based on the direction of atmospheric pressure fluctuation.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to overcome these conventional drawbacks and to provide a rain or shine information display device that is compact and capable of accurately displaying weather conditions.

[Means for solving problems]

Therefore, in the present invention, a plurality of display elements each displaying a different weather condition in response to changes in atmospheric pressure, an absolute pressure sensor that detects changes in atmospheric pressure as an electrical signal, and the plurality of display elements and absolute pressure sensor are provided. The present invention is characterized by comprising a power supply device for driving the sensor, and a signal processing device for lighting one of the corresponding display elements according to fluctuations in the signal from the absolute pressure sensor.

[Effect]

As the atmospheric pressure changes, the output from the absolute pressure sensor changes. Then, the signal processing device lights up the corresponding display element in accordance with the change in the output of the absolute pressure sensor. Here, lighting includes blinking.

Therefore, an observer can accurately grasp the weather condition by looking at which display element is lit among the plurality of display elements. Moreover, it does not require a motor like conventional ones.
The device can be made smaller.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 shows a block diagram of the rain or shine information display device of this embodiment. The rain or shine information display device can be broadly divided into power supply device 1.
, an absolute pressure sensor 41 that is driven by this power supply device 1 and detects changes in atmospheric pressure as an electrical signal, an amplifier circuit 51 that amplifies the signal from this absolute pressure sensor 41, and an output signal from this amplifier circuit 51 that converts the output signal into a digital signal. A to convert into a signal
The /D conversion circuit 61 and the interrupt signal generation circuit 71 display different weather conditions (here, four weather conditions: sunny, sunny after rain, sunny then rain, and rain) in response to changes in atmospheric pressure. Light emitting diode LED as four display elements
, - a display circuit 81 including LED4, and a microcomputer 91 as a signal processing device that blinks one of the corresponding light emitting diodes LED, -LED4 based on the signal from the A/D conversion circuit 61; , is composed of.

The power supply device 1 includes a battery 11 connected to the microcomputer 91.
, a constant voltage circuit 21 connected to the microcomputer 91 via a transistor 20 constituting a power switch of an analog circuit, and this constant voltage circuit 21 and the absolute pressure sensor 41.
and a constant current circuit 31 connected between. The constant voltage circuit 21 includes a Zener diode 22), a resistor 23 for setting the bias current of the Zener diode 22, and two resistors 24 and 25 for voltage setting, and sets the cathode side of the Zener diode 22 to a constant voltage. . The constant current circuit 31 includes an operational amplifier 32 and three resistors 33.
, 34.35. The voltage of the constant voltage circuit 21 is connected to the input terminal of the operational amplifier 32 through a resistor 33.3.
A reference voltage divided by 4 is applied, and a feedback voltage through the absolute pressure sensor 41 and the resistor 35 is applied to the negative input terminal. As a result, the operational amplifier 32 operates so that a constant potential is maintained between the resistor 35 and the ground, thereby forming a circuit in which a constant current flows between the input terminals of the absolute pressure sensor 41.

The absolute pressure sensor 41 is a resistance bridge type sensor that uses the so-called piezo effect, in which a resistor is deposited in a bridge shape on a diaphragm that deforms according to changes in atmospheric pressure, and the output voltage VA at the output terminal changes depending on changes in atmospheric pressure.

This is a structure in which VB changes.

The amplifier circuit 51 is a differential input type DC amplifier consisting of two operational amplifiers 52, 53 and resistors 54, 55, 56, 57, and output voltage V from the absolute pressure sensor 41,
■□ is amplified to V and output. In other words, V8=(1+10/9) VB -(1+8/7)
The A/D conversion circuit 61, which is a VA, converts the output ■s of the amplifier circuit 51 into a digital signal, and is composed of an operational amplifier 62), a transistor 63, a resistor 64, and a capacitor 65. The output V of the amplifier circuit 51 is connected to the input terminal of the operational amplifier 62. Now, when the base potential of the transistor 63 is set to the "I" level, the collector potential of the transistor 63 drops to VCC, so the output of the operational amplifier 62 is at the "■1" level. On the contrary, 1~
If the base potential of Ranjistaro 3 is [LJ level],
Since the integrating circuit of the resistor 64 and the capacitor 65 operates, the potential at one input terminal of the operational amplifier 62 gradually rises, and the moment it becomes higher than the potential at the tenth input terminal, the output of the operational amplifier 62 is inverted to the "L" level.

The microcomputer 91 determines the base potential of the transistor 63 -)J
< r L Start counting a certain period at J level,
Counting is stopped when the output of the operational amplifier 62 is inverted to "L" level. Therefore, the count value becomes a value proportional to the voltage at the 4-input terminal of the operational amplifier 62. Note that in order to improve the accuracy of the integration time between the resistor 64 and the capacitor 65, a constant voltage is applied to the resistor 64 from the constant voltage circuit 21.

The interrupt signal generating circuit 71 is composed of a diode 72, a capacitor 73, a resistor 74, and a CMOS inverter 75. When the transistor 20 is turned on, the capacitor 73 is charged with electric charge. After the transistor 20 is turned off, the electric charge charged in the capacitor 73 is
It is gradually discharged through the resistor 74. This signal is CMO
Since the interrupt signal is applied to the interrupt signal input terminal of the microcomputer 91 through the S inverter 75, the interrupt signal is applied to the microcomputer 91 at the moment the output of the CMOS inverter 75 is inverted from the "H" level to the "I" level.

The microcomputer 91 enters a standby state after turning off the transistor 20, and becomes active again when the interrupt signal is input. In standby state, the analog circuits are turned off, so the current consumption is low, and therefore
The overall power consumption is reduced. Furthermore, at predetermined time intervals (for example, about 5 minutes), signals from the absolute pressure sensor 41 are captured multiple times, 16 times in this case, and their average value is determined. Then, this average value is compared with the average value before a predetermined interval time, and if there is a change, the new average value is updated and stored, and in response to the change, one of the light emitting diodes L ED , ~ L E D a
lights up.

92 is a clock oscillator for the microcomputer 91; 93 is a diode 94 and a capacitor 95; 96 is a capacitor for noise prevention; 97 is an LED connected in parallel with the battery 11;
A capacitor 98 is a test terminal for preventing voltage drop during blinking. The test terminal 97 is used as a check terminal during manufacturing.

Next, the operation of this embodiment will be explained with reference to FIGS. 2 to 4.

As shown in the main flowchart of FIG. 2, first, in step (hereinafter abbreviated as ST-) 1, the analog circuit is turned on, that is, the transistor 20 is turned on. Next, 5T-2 displays I and ED2 to show the state of clear skies after rain.
After flashing, clear the time counter to "0" with 5T-3.

Next, at 5T-4, atmospheric pressure measurement is performed. This includes:
As shown in the subroutine of FIG. 3, first, the data measured for the first time is inputted, then the data measured for the second time is inputted, and the measurement data for 16 times are inputted in sequence. Thereafter, the data for the 1st to 16th times are added, the added data divided by 16 is calculated, the result is processed for 7 to 8 people, and the process returns to the main routine.

Next, at 5T-5, T-ED n to be blinked is selected. To do this, as shown in the subroutine of FIG. 4, it is first determined whether the previously stored average atmospheric pressure data HD is higher than the newly obtained average atmospheric pressure data ND. If HD is higher than ND, that is, if the atmospheric pressure is decreasing, it is then determined whether the difference between the two is "5" or more.

If the difference is not 5 or more, the process returns to the main routine. If the difference is 5J or more, it is then determined whether the LED, which indicates sunny conditions, is lit.If the LED is lit, it will display sunny and then rain conditions. Select L E D 3, while LED,
If is not lit, the rain condition will be displayed L E
D4 is selected, after which the ND is updated and stored in place of the HD, and then the process returns to the main routine.

On the other hand, if HD is not higher than ND, that is, if the atmospheric pressure is rising, then the difference between the two is "5".
Determine if it is the above. If the difference is not 5 or more, the process returns to the main routine.

If the difference is 5 or more, display the rain condition L E
Determine whether D4 is lit. L.E.D.

If is lit, it will indicate the rainy and then sunny condition.L
ED 2 is selected, and on the other hand, when LED 4 is not lit, the LED displays the clear weather condition.

is selected, after which the ND is replaced with the HD and updated and stored, and then the process returns to the main routine.

Next, at 5T-6, the LED selected in the preprocessing is turned on, and then at 5T-7, for a certain period of time (for example, about 1
LED lit after seconds) have elapsed.

Turn off the light. After this, at 5T-8, the analog circuit is turned off. Then, since the electric charge charged in the capacitor 73 is discharged through the resistor 74, an interrupt signal is given to the microcomputer 91 after a predetermined period of time.

Next, at 5T-9, the presence or absence of an interrupt signal is detected.

If there is an interrupt signal, the analog circuit is turned on at 5T-10, then the time counter +1 is processed at 5T-11, and the time counter 16 is determined at 5T-12. If the time counter≠16, the process returns to 5T-4. If the time counter is 16, proceed to 5T-13.

That is, initially, the processes from 5T-4 to ST-1, 2 are repeated 16 times. Therefore, at first, the atmospheric pressure is measured each time, and the LED blinks based on the measurement result.
, are selected, so that the LED fi corresponding to the current atmospheric pressure can be quickly blinked.

Now, if we proceed to 5T-13, we will set the time counter to 0.
After clearing, the processes of 5T-14 to 5T-21 are sequentially performed. Note that the processing of 5T-14 to 5T-21 is the same as the processing of 5T-4 to 5T-11 described above, so a description thereof will be omitted. After the processing at 5T-21, the time counter 256 is determined at 5T-22. If the time counter≠256, the process returns to 5T-16. Therefore,
5T-14 barometric pressure measurement and 5T-15 LED. After selection of , the processes 5T-16 to 5T-22 are repeated 256 times (about 5 minutes). During this time, the selected LED is blinking.

On the other hand, in the case of time counter 256, 5T-14
Return to Therefore, in this state, atmospheric pressure measurements are performed approximately every 5 minutes, and the selected L E
D, , is blinking.

Therefore, according to this embodiment, fluctuations in atmospheric pressure are detected as electrical signals, this output is amplified and then converted into a digital signal, which is input to the microcomputer 91. The microcomputer 91 processes the output signal in a predetermined manner. Since we have made it possible to light up any of the light emitting diodes LED,~LED4 that display different weather conditions, the light emitting diode LED that is lit
,~You can accurately grasp the weather condition just by looking at the LED 4. In addition, since a motor corner is not required as in the conventional case, the device can be made smaller.

Also, in the microcomputer 91, initially 5T-4 to 5T-12
By repeating the steps up to 16 times, in other words, measuring the atmospheric pressure each time, we made the ■, ED, and corresponding to the atmospheric pressure blink, so that we can quickly make the ■, ED, and l corresponding to the current atmospheric pressure blink. be able to.

After the LED corresponding to the current atmospheric pressure started blinking, the process from 5T-16 to 5T-22 was repeated 256 times, so at intervals of about 5 minutes corresponding to the number of times. You can check changes in atmospheric pressure.

In addition, the microcomputer 91 captures the output from the absolute pressure sensor 41 multiple times at predetermined time intervals, calculates the average value of these, and depending on the difference between this average value and the average value before the predetermined time interval, the LED, Since any one of the ~LED4 is made to blink, changes in atmospheric pressure can be detected accurately and with high precision.

Further, since the battery 11 is used as the power supply device 1, it can be made smaller and can be constructed as a portable device that is particularly convenient to carry when traveling.

Moreover, a constant voltage circuit 21 and a constant current circuit 31 are provided between the battery 11 and the absolute pressure sensor 41, and the absolute pressure sensor 41
Since a constant current is caused to flow through the absolute pressure sensor 41, the temperature characteristics of the absolute pressure sensor 41 can be improved.

Furthermore, since a bridge type sensor in which a resistor is deposited on a diaphragm is used as the absolute pressure sensor 41, fluctuations in atmospheric pressure can be detected with high sensitivity.

In addition, in implementation, the power supply device 1 is not limited to the battery 11 described in the above embodiment, and an AC power supply may be used.

Further, the absolute pressure sensor 41 is not limited to the resistance bridge type sensor described in the above embodiment, but may be any sensor as long as it can detect changes in atmospheric pressure as an electrical signal with high sensitivity.

Furthermore, in the above embodiment, the microcomputer 91 captures 16 signals from the absolute pressure sensor 41 at predetermined time intervals and calculates the average value of these signals. You may also do so.

In addition, in the above embodiment, the weather conditions are divided into four conditions, that is, sunny, sunny after rain, rain after sunny, and rainy conditions. You can.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a rain or shine information display device that is small and can accurately display weather conditions.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is an overall circuit diagram, Fig. 2 is a flowchart showing the main routine, Fig. 3 is a flowchart showing the barometric pressure measurement subroutine, and Fig. 4 is the LED, , is a flowchart 1 showing a selection subroutine. DESCRIPTION OF SYMBOLS 1... Power supply device, 11... Battery, 21... Constant voltage circuit, 31... Constant current circuit, 41... Absolute pressure sensor, 51... Amplification circuit, 61... A/ D conversion circuit, 7
1... Interrupt signal generation circuit, 81... Display circuit, L
E D , ~LED4... Light emitting diode, 91...
・Microcomputer.

Claims (5)

[Claims] (1) A plurality of display elements that each display different weather conditions in response to changes in atmospheric pressure, an absolute pressure sensor that detects changes in atmospheric pressure as an electrical signal, and a power source that drives the plurality of display elements and the absolute pressure sensor. What is claimed is: 1. A fair or rainy weather information display device, comprising: a signal processing device that lights up one of the corresponding display cables according to fluctuations in a signal from the absolute pressure sensor. (2) In claim 1, the display element is composed of four display elements that display the following conditions: sunny, sunny after rain, sunny then rain, and rain in response to changes in atmospheric pressure. A rain or shine information display device. (3) In claim 1 or 2, the weather/rain information display is characterized in that the absolute pressure sensor is a sensor in which a resistor is fixed in a bridge type to a diaphragm that deforms in response to changes in atmospheric pressure. Device. (4) In any one of claims 1 to 3, the power supply device includes a battery that drives the plurality of display elements and an absolute pressure sensor, and a constant voltage that makes the voltage of the battery constant. A rain or shine information display device comprising: a circuit; and a constant current circuit provided between the constant voltage circuit and the absolute pressure sensor. (5) In any one of claims 1 to 4, the signal processing device acquires signals from the absolute pressure sensor multiple times at predetermined time intervals and calculates an average value based on these signals. A rain or shine information display device, characterized in that one of the corresponding display elements is turned on according to the difference between this average value and an average value before a predetermined time interval.