JPS639754Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an opening/closing device for a ventilation window of a greenhouse such as a glass house for greenhouse horticulture or a greenhouse.

In recent years, greenhouses have rapidly become larger and more centrally managed, but forced ventilation using ventilation fans is being avoided due to insufficient ventilation and poor efficiency, and natural ventilation is being reconsidered. In order to reduce the labor required for ventilation, the opening and closing of ventilation windows has been automated using electric motors, etc. Generally, the temperature inside the greenhouse is detected using a thermistor, etc.
If the temperature is higher than the set temperature, the ventilation window is opened, and if it is lower, it is closed, and the temperature inside the greenhouse is automatically ventilated using a proportional control method that changes the opening width depending on the size of the difference from the set temperature. However, in times of rain or strong winds, the ventilation windows must be closed over temperature conditions, etc., and there is a need for a device that can perform this operation efficiently in addition to the automatic ventilation described above.

The present invention provides a greenhouse ventilation window control device that satisfies these conditions, and will be described in detail below with reference to the drawings.

Fig. 1 shows an outline of this device. In order to control the opening and closing of the ventilation window 2 installed in the greenhouse 1 for greenhouse horticulture, an electric motor 3, which is opened and closed by a speed reduction mechanism (not shown), etc., is shown in Fig. 2. The contents include a controller 4, a thermistor 5 for temperature detection installed at an appropriate location in the greenhouse 1, a potentiometer 6 that operates in conjunction with the opening and closing of the ventilation window 2, and a rain sensor whose contacts 7 open in the event of rain or strong winds. (not shown) and a wind sensor (not shown).

The potentiometer 6 is set so that the sliding contact C is approximately at the center when the ventilation window 2 is fully closed, that is, the resistance value Rac=Rbc, and when the ventilation window 2 is opened, the potentiometer 6 is The resistance value Rac between A and C becomes small, and when it is closed, B- of potentiometer 6
The resistance value Rbc between C and C is set to be small.

In such a configuration, if the circuit changeover switch 8 is set to A, the temperature setting variable resistor 9 will be turned on when the contact 7 is closed during normal weather where no rain or wind is detected. When the set temperature matches the temperature in the greenhouse 1, the output terminal T ₁ of the bridge circuit consisting of the thermistor 5, fixed resistors R ₂ and R ₃ , one end Rac of the potentiometer 6, and the variable resistor 9, The voltages of T ₂ are equal and voltage comparator 1
1a and 11b are electrically connected, and Schmitt circuits 13a,
13b is reversed, the relays 14a and 14b are de-energized, the motor 3 does not rotate, and the ventilation window 2 remains as it is.

When the temperature in the greenhouse 1 is higher than the set temperature, the voltage at the output terminal _T1 of the bridge circuit becomes higher than the voltage at _T2 , the voltage comparator 11a becomes conductive and the voltage comparator 11b is cut off, and as a result, The Schmitt circuit 13a is reversed, the closing relay 14a is de-energized, the Schmitt circuit 13b is not reversed and the opening relay 14b is energized, the electric motor 3 rotates in the opening direction, and the ventilation window 2 opens. 2, the sliding contact C of potentiometer 6 moves and resists
As the value of Rac becomes smaller, the bridge circuit gradually becomes balanced, the voltage comparator 11b becomes conductive, and therefore the Schmitt circuit 13b is inverted and the open relay 14b is turned on.
becomes de-energized and the electric motor 3 stops.

When the indoor temperature in the greenhouse 1 is lower than the set temperature, the voltage at the output terminal _T1 of the bridge circuit becomes lower than the voltage at _T2 , the voltage comparator 11a is cut off and the voltage comparator 11b is made conductive, and the schemitsu Circuit 13a
is not reversed and the closing relay 14a is energized, the Schmitt circuit 13b is reversed and the opening relay 14b is de-energized, the motor 3 rotates in the closing direction, the ventilation window 2 is closed, and at the same time the ventilation window 2 is linked. As a result, the sliding contact C of the potentiometer 6 moves and the value of the resistor Rac increases, the bridge circuit is balanced, the voltage comparator 11a becomes conductive, and the Schmitt circuit 13a becomes conductive.
is reversed, the closing relay 14a becomes de-energized, and the motor 3 stops. On the other hand, when the ventilation window 2 is fully opened, the resistance value between B and C of the potentiometer 6
As Rbc increases and the voltage at point B decreases,
Adjust the variable resistor 10b so that the voltage comparator 12b is cut off at that time.Furthermore, when the ventilation window 2 is fully closed, the resistance value Rbc between B and C of the potentiometer 6 becomes small, and B Since the voltage at the point becomes high, adjust the variable resistor 10a so that the voltage comparator 12a is cut off at that time.By doing this, when the ventilation window 2 is fully opened, the transistor 15b is cut off and the voltage is passed through the diode 16b. A positive voltage is added to the input of the Schmitts circuit 13b and reversed, and the opening relay 14b becomes de-energized and the motor 3
stops. Conversely, when the ventilation window 2 is fully closed, the transistor 15a is cut off, a positive voltage is added to the input of the Schmitt circuit 13a through the diode 16a, and the circuit is reversed, and the closing relay 14a is de-energized and the motor 3 is stopped. These two operations are performed regardless of temperature. If rain or wind is sensed and contact 7 opens, the voltage at terminal T ₁ will be lower than the voltage at terminal T ₂ , similar to the closing operation described above, and closing relay 3 will close. direction to close the ventilation window 2.

Note that this operation is also performed regardless of temperature.

Next, when the switch 8 is turned to ``low'', the thermistor 5 is disconnected, the voltage at the terminal _T1 becomes lower than the voltage at the terminal _T2 , and the aforementioned closing operation is performed.

Next, when the switch 8 is set to H, the thermistor 5 is short-circuited, and the voltage at the terminal _T1 becomes higher than the voltage at the terminal _T2 , as in the case of the opening operation described above, and the opening relay 14b is energized. The electric motor 3 rotates in the opening direction and the ventilation window 2 opens. If rain or wind is detected and the contact 7 opens, the voltage at the terminal _T1 becomes lower than the voltage at the terminal _T2 , and the closing operation described above is performed.

By repeating these operations, the temperature inside the greenhouse 1 is not only automatically maintained, but also proportional control and limit detection can be performed using only the wiring from the potentiometer 6. They can be installed separately and maintenance is therefore easy. Furthermore, since the control section is also constructed from a simple circuit, it can be provided at low cost.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the present invention, and FIG. 2 is a control circuit. 1 is a greenhouse, 2 is a ventilation window, 3 is an electric motor, 4 is a controller, 5 is a temperature detection thermistor, 6 is a potentiometer, 7 is a contact point for a rain or wind sensor, 8 is a circuit changeover switch, and 9 is a Variable resistance for temperature setting, 1
0a, 10b are variable resistors for setting reference voltage, 11
a, 11b, 12a, 12b are voltage comparators, 13
Schmitt circuits a and 13b.

Claims (1)

[Scope of utility model registration request] In a greenhouse ventilation window control device that measures the temperature inside the greenhouse and automatically opens and closes the windows using signals from the measured value, the system measures outdoor rainfall and wind speed, converts these measured values into electrical signals, A circuit that closes the ventilation window with priority over the electrical signal based on the temperature inside the greenhouse when at least one of these two electrical signals exceeds a predetermined set value, and a circuit that forcibly closes the ventilation window regardless of these two electrical signals. Then, regardless of the temperature inside the greenhouse, the ventilation windows are forcibly opened, the amount of rain and wind speed outside are measured, these measured values are converted into electrical signals, and at least one of these electrical signals is set according to a predetermined setting. A greenhouse ventilation window control device that can select and use a circuit that closes the ventilation window when the temperature exceeds a certain value.