JPS589650B2 - Automatic watering device for plants - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that automatically supplies water to plants and flowers growing in pots, planters, gardens, fields, etc. The purpose of the present invention is to provide a device that can ideally supply water for a long period of time and can be made cordless.

Conventionally, automatic watering devices for plants have been devised that first use a soil moisture detector that measures the moisture in the soil as a change in resistance, and then detects dry conditions and supplies water. .

Such a device has a problem in detecting moisture, and the contact resistance between the soil damage and the moisture detection electrode becomes very large, resulting in poor detection sensitivity.

Furthermore, the resistance value varies greatly even at the same moisture content depending on the salt concentration during the soil breakage and the soil breakage temperature, and the service life is short.

Therefore, in the automatic water supply device using the above device, there is a risk that the area around the roots of the plant becomes overly humid or becomes too dry due to malfunction.

The second device operates a solenoid valve or pump using a timer to periodically replenish water. It carried an even greater risk.

By the way, the amount of water evaporation from the leaf surface of plants and the amount of water evaporation from the ground in cultivated land is influenced by factors such as temperature, solar radiation, soil moisture, and humidity, but the amount of water evaporating from the leaf surface of plants and the amount of water evaporating from the ground in cultivated land are influenced by factors such as temperature, solar radiation, soil moisture, and humidity, but solar radiation and temperature have a large effect on Depends on it.

Furthermore, there is a strong correlation between solar radiation and temperature.

When the amount of solar radiation is high (and the temperature is high), evapotranspiration becomes active, reducing the amount of water in the soil and increasing the amount of water required by plants.

Therefore, it is preferable that sufficient water is supplied to plant roots when the amount of solar radiation is high, and that water is not supplied when there is little evapotranspiration of plants or fields during rainy weather or at night.

The present invention supplies water by taking advantage of the fact that the water requirement of the roots of the plant described above is closely related to the amount of solar radiation, and completely overcomes the above-mentioned conventional drawbacks.

The feature of the present invention is a device that stores solar radiation converted into electrical energy by solar cells in a power storage device, and supplies water to plants in an amount equivalent to the stored energy, that is, water proportional to the cumulative solar radiation. It is.

This will be explained below with reference to the drawings.

In FIG. 1, a solar cell 1 generates electrical energy corresponding to the intensity of solar energy irradiated onto a light receiving surface, which is charged to a power storage unit 3 via a reverse current prevention diode 2.

The solenoid valve drive circuit section 4 is connected in parallel with the power storage section 3. When the voltage of the power storage section 3 reaches a certain value or higher, the drive circuit is activated, the solenoid valve 5 becomes energized, and water flows through the water supply pipe 6. The water is supplied to the plants 8 through the brine pipe 7.

As the power storage unit 3, a secondary battery such as a lead storage battery or a Ni-CD storage battery, or a large capacity capacitor having a capacity of IF to 100F is used.

FIG. 2 is an example of a control circuit diagram of an automatic irrigation system, in which electrical energy generated by the solar cell 1 is stored in a capacitor 9 of a power storage unit.

The output voltage of the capacitor 9 increases approximately in proportion to the amount of accumulated electricity, that is, the integrated amount of solar radiation on the light receiving surface.

In the drive circuit section 4 connected in parallel with the capacitor 9, a Zener diode 11 is connected so that the gate voltage of the trigger element 10, for example a unijunction transistor, is kept constant even if the output voltage of the capacitor 9 increases.
The output voltage of the capacitor 9, which has increased more than the gate voltage, is added as the anode voltage of the trigger element 10, and the trigger element 10 is turned on, making the transistor 12 conductive.
A DC current flows through the capacitor 3, and the solenoid valve 5 is opened until the capacitor 9 finishes discharging, and water is supplied.

As soon as the capacitor discharge ends, trigger element 1
0 returns to the OFF state and charging of the capacitor 9 is started again.

The power storage unit 3 can also be used by connecting a secondary battery in series.

In this case, the drive circuit section 4 is configured so that the gate voltage of the trigger element 10 is set equal to the voltage in the charging state of the secondary battery, and the voltage at which the ON state is turned on (trigger voltage) is set to be the voltage at the time of overcharging. be done.

Furthermore, instead of supplying water by opening and closing a solenoid valve, water is supplied by driving a pump. is also possible with a similar configuration.

The water supply amount and water supply interval in the automatic water supply device according to the present invention are determined by the output of the solar cell 1, the electric capacity of the power storage unit 3, and the amount of solar radiation.

That is, under a constant amount of solar radiation and solar cell output, if the electrical capacity of power storage unit 3 is large, the water supply interval becomes longer and the amount of water supplied at one time becomes larger.

On the other hand, when the electric capacity of power storage unit 3 is small, the water supply interval is short and the amount of water supplied at one time is small.

Also, under a constant solar cell output and storage unit capacity,
The watering interval is determined by an arbitrary value of solar radiation (if the conversion efficiency of the solar cell is constant, it corresponds to the capacity of the power storage unit). The watering interval becomes shorter, and when it is cloudy or cloudy and the amount of sunlight is low (there is less water evaporation from the plant), the watering interval becomes longer, and on rainy days or at night, electricity cannot be stored in the power storage unit 3. Water supply will not be provided.

As described above, the automatic water supply device according to the present invention can supply water in proportion to the amount of solar radiation to the plants by determining the output of one solar cell and the capacity of three power storage units according to the number of plants and the cultivation area. The inconveniences of periodic watering using a soil moisture meter or watering using a soil moisture meter can be completely eliminated, and an ideal watering device can be provided for plants.

Example 1 When used for irrigation of the field 10a The amount of evapotranspiration in the vegetable field on a sunny day in midsummer in the field 10a reaches 5 to 6 m3 per day.

Output capacity 15.0V 500mA (incident energy 100
When m-Δ1) is used, the power storage unit 3 is supplied with 12V, 2. Uses OAH lead acid batteries.

A solenoid valve 5 directly connected to a water pipe with a water pressure of 1-8 kg/cm' is operated at DC 12 V and 2 A, and a flow rate of 50 l/min is obtained.

The water that has passed through the electromagnetic valve 5 passes through a water supply pipe 6 and is supplied to the roots of cultivated plants 8 through a hole in a irrigation pipe 7.

The gate voltage of the electromagnetic valve drive circuit 4 is set to 12.6 V, which is the open voltage of the lead acid battery used in the power storage unit 3 in the charged state, and the trigger voltage is set to 13.8 V, which is the overcharge voltage of the lead acid battery. Set to .

The amount of electricity obtained from the above solar cell on a clear day in summer is 5A.
h and the charging efficiency of the lead-acid battery used is 80%, the lead-acid battery can be charged and discharged twice.

The amount of irrigation by one discharge is 50l x 60min = 3 tons/time, and 2 times/day can provide 6 tons/day of irrigation, which can sufficiently compensate for the amount of evapotranspiration during midsummer in a 10a field. .

Embodiment 2 Water supply of potted plants on a flower stand FIG. 3 is an example in which the automatic watering device of the present invention is applied to potted plants on a flower stand.

In the figure, 1 is 3.6V5mA (incident energy 10
It is a solar cell with an output of 0 mw/cm) and has a reverse current prevention diode inside.

Reference numeral 21 denotes a control box containing a power storage unit and a pump drive circuit, and is electrically connected to the solar cell 1 through a lead wire 22 and to the pump 24 through a lead wire 23 .

The power storage unit inside the control box 21 has a withstand voltage of 3.5V and 20F.
A capacitor of 1 is used, and the drive circuit is set to a gate voltage of 2.4 V and a H-gauge voltage of 3.0 ■.

The pump 24 has a DC of 3.0 to 1. Driven by OV and above 20F
With one discharge of the capacitor, approximately 2 liters of water can be pumped up from the water supply tank 25 and supplied to the potted plants 27 placed on the flower stand 26 through the water supply pipe 28.

The solar radiation energy during clear weather in summer is about 100 mw/cm', and when the solar cell 1 and the 20F capacitor are used as a power storage unit, water is automatically supplied to the potted plants once every 3.5 hours.

Of course, water is not supplied at night or during rainy days.

As described above, the automatic water supply device according to the present invention is a device that is based on the integrated value of solar radiation, which has a high correlation with the amount of transpiration in plants and the amount of evapotranspiration in fields, and its application ranges from home use to agricultural use. The present invention has great industrial value in that it has a wide range of advantages.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an automatic water supply device according to the present invention, FIG. 2 is a control circuit diagram of the same device, and FIG. 3 is a block diagram of a flower stand equipped with the device of the present invention. 1...Solar cell, 3...Power storage unit, 4.
... Solenoid valve circuit section, 5 ... Solenoid valve, 6.
...Water supply pipe, 7...Irrigation pipe.

Claims (1)

[Scope of Claims] 1. A device for supplying water to a culture medium for plant cultivation, which includes a drive circuit that drives a water supply section consisting of a solar cell, a power storage section, a pump, and/or a solenoid valve, and obtains water according to the amount of solar radiation. automatic water supply to plants, comprising: storing power from the solar cell in the power storage unit; and when the amount of electricity stored in the power storage unit reaches a predetermined value, the stored power drives a water supply unit to perform automatic watering; Device. 2. The automatic water supply device for plants according to claim 1, which uses a power storage unit in which the amount of stored electricity and the output voltage exhibit linear characteristics. 3. The plant according to claim 1, which uses a secondary battery as the power storage unit and has a drive circuit for a water supply unit that operates by detecting a voltage increase when the secondary battery is overcharged. Automatic water supply device.