JPS62284139A - Method of temperature control and ventilation of hothouse - Google Patents

Abstract

PURPOSE:To effect temperature control in a hothouse and forced room ventilation by providing a ventilation fan in the upper layer section on the roof surface and an opening section in its lower layer section and hanging a lead wire which energizes a motor of the ventilation fan and providing a temperature sensing switch at the tip end of the lead wire. CONSTITUTION:A single or a plurality of ventilation fans 30 are provided in the upper layer section on the roof surface 32 of a hothouse 31 and in the lower section an opening section 33 is provided. The opening section 33 is provided with a lid 34, and in its lower section a cold water flow gutter 35, etc. are provided. The outer lid 5 of a ventilation fan 30 covers the upper section of a cylinder 1, and at the gap section 5 in the lid 5 an inner lid 8 which has a circumferential wall 9 which slides on the outer wall face of the cylinder 1 is provided, and in the circumferential wall 9 many holes 10, etc. are provided. The inner lid 8 becomes a closing device by means of a hinge by the existence of rotation of a fan 3 relative to the cylinder 1. Lead wires 11 and 12 for a motor 2 are handing in the hothouse 31 and their tip ends are provided with a temperature sensing switch 13 which turns ON and OFF the current by sensing temperature. With this arrangement when the temperature is low, the cylinder 1 is closed by the inner lid 8 automatically, and when the temperature is high, the inner lid 8 is opened and effects ventilation by a forced circulation flow between the outdoor and the hothouse 31.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention The present invention mainly relates to a method for temperature control and forced ventilation in a greenhouse. can also be used.

Greenhouses are originally intended to protect tropical plants from low temperatures in winter, or to encourage the cultivation of plants outside of the season, and are usually enclosed in a closed room with transparent glass plates or vinyl. , so-called Yuru.

It takes advantage of the greenhouse effect.

Therefore, if summer continues as it is, the greenhouse will inevitably be forced into a high temperature state, and the plants in the greenhouse will become stuffy and wither.

Therefore, skylights or gable windows are installed to achieve natural ventilation by utilizing the circulation flow caused by the temperature difference between the warm room and the outside air.

This skylight/gable window opens and closes depending on the temperature,
Currently, most of this is done manually, and in some cases, thermostatic systems using bimetals and microcomputer control systems with temperature sensors have been developed and used.

By the way, the skylight of a greenhouse uses the density difference due to the temperature difference between the inside of the greenhouse and the outside air to achieve natural ventilation, so in order to ensure its effectiveness, the opening area must be made as large as possible.

Most skylights are opened and closed using hinges, so the automation system itself is extremely simple, but since the opening area is large, it is also difficult to For countermeasures, etc., it has to be a sturdy, six-layer, large-scale device, which inevitably leads to high costs.

In recent years, as the use of garden greenhouses and the like has increased, there has been a strong demand for automated ventilation systems other than the conventional skylight system. The present invention shows one example thereof.

Basically, as shown in the schematic cross-sectional view of FIG.

An opening is provided in the lower part of the greenhouse, and a ventilation fan is provided in the upper part.The ventilation fan is energized by a temperature-sensitive switch that automatically turns on and off the current depending on the temperature, and the inner cover of the ventilation fan's outlet is forced to close. A method that uses exhaust wind pressure to operate upward to open the air, and creates a forced circulation flow from the opening in the lower layer to the exhaust outlet in the upper layer by rotating a ventilation fan, thereby controlling temperature and performing forced ventilation. It is.

Therefore, since the exhaust ports for ventilation are concentrated at one point, the configuration is extremely simple and control is easy.

To describe an example of this, Fig. 1 is a sectional view of a ventilation fan, Fig. 2 is a sectional view of a temperature-sensitive switch using a shape memory alloy, and Fig. 3 is a schematic sectional view of a greenhouse. It is a diagram.

The ventilation fan 30 connects a cylinder 1 made of aluminum or plastic to a greenhouse 3 with a cylindrical, conical, or rectangular cylinder 1.
1 is fixed to the upper layer of the roof surface 32, and a support 4 is installed inside the tube 1.
Set the motor 2 according to the following, and connect it to the motor 2 and place the fan 3.

The fan 3'ri may be an axial flow fan, a hashiroco type, or a turbo type.

A hemispherical or cylindrical outer cover 5 with a larger diameter than the tube 1 is installed with several supports 7 to cover the upper part of the tube 1, keeping a gap 6 between it and the tube 1. do.

It has an appropriate self-weight in the gap 6 at the top of the cylinder 1, has a hemispherical or ring-shaped upper surface, and the peripheral part is the cylinder 1.
A peripheral wall 9 that slides lightly while keeping an appropriate distance from the outer wall surface of the
Place the inner lid 8 with a

A large number of holes 10 can be provided in the peripheral wall 9, or a fence-like structure can be provided so that the exhaust air generated by the rotation of the fan 3 can easily pass through.
At the same time, the inner cover 8 is pushed up by the exhaust air pressure generated by the rotation of the fan 3, opening the cylinder 1, and
The peripheral wall 9 serves as a guide to ensure the repeated operation of bringing the cylinder 1 into a closed state by causing the inner lid 8 to fall under its own weight when the rotation of the cylinder 3 stops.

The inner cover 8 is opened and closed by moving it up and down relative to the cylinder 1 depending on whether or not the fan 3 rotates.

Similar effects can be obtained by adopting a method such as a single hinge method as shown in FIG. 4 or a double hinge method as shown in FIG.

Lead wires 11 and 12 for energizing the motor 2 are hung down to an arbitrary length inside the greenhouse 31, and a temperature-sensitive switch 13 is placed at the tip of the lead wires to sense the temperature and turn on/off the current.

The temperature-sensitive switch 13 includes a shape memory alloy, a bimetal, a solenoid valve with a thermocouple, etc., and turns on/off the current according to a predetermined temperature.

As an example, FIG. 2 shows a case where a shape memory alloy is incorporated.

Spring plates 16 and 17 with good conductivity are set parallel to the insulating support column 14 at appropriate intervals, and a contact point 21 is attached to one end.
Attach terminals 19 and 20 to the other end, and connect lead wires 11 and 1.
Connect 2.

A bidirectional shape memory alloy coiled spring 18 is set to protrude from the spring plate 16 with the support 15.

It is assumed that the coiled spring 18 made of a bidirectional shape memory alloy has a shape memorized so that it is in a contracted tight state at low temperatures and in an expanded state at high temperatures.

Therefore, when the temperature of the greenhouse reaches a predetermined temperature, which is higher than the lower temperature side, the spring 18 expands, and the spring plate 16
is bent with the spring plate 16', the contact point 21 is connected, and the lead wires 11 and 12 are connected and energized.

On the other hand, if the temperature decreases, the spring 18 contracts, so that the spring plate 16' returns to its original state as the spring plate 16, and the contact point 21 is disconnected.

In this way, the current can be turned on and off due to temperature changes.

In this case, the power source used may be either an alternating current of normal power or a direct current of a solar battery.

However, the motor 3 shall be adapted to this.

The above is the configuration of the ventilation fan 30.

One or more ventilation fans 30 are fixed to the upper part of the roof surface 32 of the greenhouse 31, and an arbitrary number of openings 83 of an appropriate size are provided in the lower part of the wall surface of the greenhouse 31.

A rectangular or curved lid 34 is attached to the opening 33 to prevent wind, rain, etc., and a water tank or cold water flow 35 is placed below the lid 34. This may be the cooling medium of a cooling device.

If desired, it is also possible to take in the outside air while cooling it by passing the cold water flow 35 through a group of thin tubes or a finned tube body. Further, a blower may also be provided on the side of the opening 33 to provide forced air supply.

Further, as a measure against low temperatures, it is desirable to be able to close the opening 33.

As described above, the method of temperature control and ventilation of a single greenhouse is (1) installing one or more ventilation fans 30 in the upper layer of the roof surface 32 of the greenhouse 31, and providing an opening 83 in the lower layer; .

(2) A lid 34 is attached to the opening 33, and a water tank or a cold water flow 35 is provided at the bottom thereof. Further, if desired, a blower may be provided on the side of the opening 33 to provide forced air supply.

(3) For ventilation @aO, a motor 2 and a fan 3 are set inside a cylindrical or conical tube 1, and an outer cover 5 covers the top of the tube 1 while maintaining an appropriate gap 6 with the tube 1. An inner cover 8 having a circumferential wall 9 that slides on the outer wall surface of the cylinder 1 is placed in the gap 6, the inner cover 8 has an appropriate weight, and the circumferential wall 9 is provided with a large number of holes 10, etc. The text is that the inner lid 8 has a hinge system that connects the fan 3 to the tube 1.
The opening/closing device is based on the presence or absence of rotation.

Lead wires 11 and 12 for energizing the motor 2 are hung in a greenhouse 31 at arbitrary lengths, and a temperature-sensitive switch 18 is placed at the tip of the lead wires to sense the temperature and turn on/off the current.

With the above configuration, the tube 1 is automatically closed by the inner lid 8 when the temperature is low, and the inner lid 8 is opened when the temperature is high, and the ventilation fan 30 is applied through the opening 33 to force the air between the outside world and the greenhouse 31. This is a temperature control and ventilation method for a greenhouse, which is characterized by ventilation through circulating flow and thereby temperature control.

The specific operation of the greenhouse temperature control and ventilation method based on the above configuration is as follows.

Conventional greenhouse ventilation using skylights is always open during high temperatures in summer, closed during low temperatures in winter, and closed during spring and fall.

The general pattern is that the mind is open and the night is closed.
The smaller the greenhouse, the more sensitive it is to external temperature fluctuations, and it may need to be opened and closed several times a day during spring and fall.

According to the present greenhouse temperature control and ventilation method, it can be replaced by automated operation as described below.

That is, if the temperature inside the greenhouse 31 is to be ventilated and adjusted by opening and closing with the temperature at 20°C as a boundary, the temperature inside the greenhouse 31 is shifting from the low temperature side to the high temperature side.

Now, if the temperature exceeds 20°C, if the temperature-sensitive switch 13 set at an appropriate position in the greenhouse 31 picks up a temperature of 20°C or more, the shape memory alloy coil spring 18 will change its shape. Due to the memory effect, the leads 11 and 11 are in an extended state, pushing the spring plate 16 and bending into the state of the spring plate 16'.
12, and power is supplied to the motor 2.

However, the shape memory alloy used here has a temperature of 20°C.
It is assumed that the shape memory effect is set to perform an expansion/contraction stroke operation using the boundary as .

Therefore, motor 2 rotates, fan 3 also rotates,
An attempt is made to exhaust the air inside the greenhouse 31.

The inner cover 8, which directly covers the cylinder 1 in a hemispherical shape or the like, is guided by the peripheral wall 9 under the pressure of this discharge wind and moves straight upward, a.
It is pushed up from the position to the b position.

However, since the peripheral wall 9 has a large number of holes 10 or is fence-like, the exhaust air easily passes through the holes 10 and between the cylinder 1 and the outer cover 5 and is discharged to the outside world.

The other suction port for this exhaust air is provided as an opening 33 in the lower part of the greenhouse 31, and the opening 33 is covered with a lid 34 in a curved shape, and a cold water flow 35 is installed directly below it. The temperature of this air flow is decreasing because of the presence of air in the greenhouse 31, or because air is sucked in from the outside world through a group of thin tubes passing through this cold water flow 35, and the temperature rise is suppressed while ventilating the inside of the greenhouse 31. That will happen.

When the inside of the greenhouse 31 shifts from a high temperature side to a low temperature side, if the temperature-sensitive switch 13 senses that the temperature has fallen below 20°C, the shape memory alloy coiled spring 18 contracts and the spring plate 16' The spring plate 16 returns to its original state, and the current flowing through the series lead wires 11 and 12 is cut off.

Therefore, the supply of electric power to the motor 2 is stopped, and the rotation of the fan 3 is also stopped.

Along with this, the exhaust air also stops, so the inner cover 8, which had been pushed up by the exhaust air pressure, is guided by its own weight to the peripheral wall 9 and moves along the outer wall surface of the cylinder l from the position b to the original position a. Return to position.

Then, the cylinder l is sealed from the upper part against the outside world. Furthermore, since there is no exhaust air, there is no suction from the opening 33. At this time, it is clear that even if the inner cover 8 is of a hinge type as shown in FIGS. 4 and 5, it will operate in the same manner.

Such operation is intended to control the temperature and ventilate the inside of the greenhouse 31, but the number of ventilation fans 30 installed may be increased depending on the size of the greenhouse, or the capacity of the motors 2 and 77 fans 3 may be increased.

Furthermore, if the temperature and method of passage of the cold water flow 35 located directly below the lid 34 of the opening 33 that serves as the air suction port are improved, for example, the method of suctioning through a group of thin tubes, the method of using a finned tube body, and the method of If a method such as placing a cooling medium from a cooling device is used, it is possible not only to simply ventilate the greenhouse, but also to lower the temperature inside the greenhouse 31 compared to the outside temperature, which is more effective in preventing stuffiness of cultivated plants and damage from pests and diseases. You can.

As mentioned above, the method of temperature control and ventilation in this greenhouse uses centralized forced ventilation, compared to the conventional method of skylighting, which expands the opening area to achieve natural ventilation. This is a method that makes it easier to operate and improves the functionality of the greenhouse.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a ventilation fan portion according to the present invention. FIG. 2 is a sectional view of a temperature-sensitive switch using a shape memory alloy. FIG. 3 is a schematic cross-sectional view of the greenhouse. FIG. 4 is a sectional view of a ventilation fan with a single-hinged inner cover. FIG. 5 is a cross-sectional view of a ventilation fan with a double-hinged inner cover. 1...Cylinder 2...Motor 3...Fan 5...Outer cover 8...Inner cover 9. Monument......Surrounding wall 13...Temperature-sensitive switch 30...
Ventilation fan 31... Greenhouse 33...
・Opening, i 310

Claims (2)

[Claims] (1) One or more ventilation fans 30 are installed in the upper part of the roof surface 32 of the greenhouse 31, and an opening 33 is provided in the lower part. (2) The ventilation fan 30 has a motor 2 and a fan 3 set inside a cylinder 1 having a cylindrical or conical shape, and an outer cover 5 covers the upper part of the cylinder 1 while maintaining an appropriate gap 6 with the cylinder 1. An inner cover 8 having a circumferential wall 9 that slides on the outer wall surface of the cylinder 1 is placed in the inner cover 8, the inner cover 8 has an appropriate weight, and the circumferential wall 9 is provided with a large number of holes 10, or, The inner lid 8 is of a hinge type and serves as an opening/closing device for the cylinder 1. Lead wires 11 and 12 for energizing the motor 2 are hung down to an arbitrary length, and a temperature-sensitive switch 13 is placed at the tip of the lead wires to sense the temperature and turn on/off the current. With the above configuration, when the temperature changes, the inner lid 8 automatically closes the tube 1 when the temperature is low, and when the temperature is high, the inner lid 8 is opened and the ventilation fan 30 is applied through the opening 33 to create a connection between the outside world and the greenhouse 31. Ventilate through forced circulation, and
A greenhouse temperature control and ventilation method characterized by temperature control