JP2016163541A - Agricultural plastic greenhouse - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic greenhouse capable of maintaining temperature in the house high in the winter and low in the summer by spreading and retracting a film according to the seasons and daytime and nighttime.SOLUTION: In an agricultural plastic greenhouse, as a first film 1 that is fixedly extended on a ceiling plane of the agricultural plastic greenhouse, a material having a high permeability in the visible light region, near-infrared region, and far-infrared region is used. Different from the first film 1, a second film 2 that can be spread/retracted over/from the ceiling plane is provided, and for the second film 2, a material permeating light in the visible light region and shielding light in the near-infrared region and far-infrared region is used.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure and characteristics of a coating for improving heat retention in winter and suppressing temperature rise in summer in an agricultural greenhouse.

Agricultural greenhouses are high prices by spreading transparent vinyl film on a frame made of metal, etc., confining solar heat and keeping the house warm, promoting crop growth and shifting the harvest time. Although the transaction is to be realized, the temperature inside the house at night falls to almost the same as the outside temperature due to the heat conduction and radiant heat of the film. Was not fully feasible. Therefore, two films are spread and spread, and an air layer of a certain thickness is provided between them, so that the air between the two films is used as a heat insulating layer to construct a greenhouse with good heat retention. Yes.
As specific prior art, there are Patent Document 1 and Patent Document 2. However, among these three paths of heat, namely conduction heat, convection heat, and radiant heat, the convection heat is blocked by sealing the entire house with a film, and the conduction heat is blocked by a double film. No action was taken against radiant heat.
On the other hand, convection heat is released by opening the side of the greenhouse and ventilating it so that the temperature inside the house rises due to sufficient sunlight entering the house during the daytime and the temperature does not rise too much in the summer. However, in summer, the temperature is usually 10 ° C. or more higher than the outside temperature, and there is a problem that the crop is damaged by high temperature or grows badly.
Then, there existed a technique of comprising the covering material of a house with the member which interrupt | blocks near infrared rays like patent document 3. FIG. However, if this technique is used, the temperature rise in the summer can be suppressed, but the temperature rise in the house is similarly suppressed in the winter, so that there is a problem that a sufficient house temperature cannot be secured.
In addition, there is a greenhouse called Nikko Greenhouse as shown in Non-Patent Document 1, but this is an emphasis on the warmth in winter, and a futon material that can be unfolded and stored on the outside of the house roof is provided. However, it is effective to block the heat conduction and radiant heat at night in winter to improve the warmth in winter, but does not have any effect on the temperature rise in summer.

JP 2002-58355 A Japanese Patent Laid-Open No. 2008-5798 JP 2006-68964 A

"November 2012 issue of modern agriculture" 88-89 pages, 128-131 pages

The problem of the present invention is that the above-mentioned prior art has a problem that the warming effect in winter is not sufficiently obtained, a problem due to a temperature rise in summer, and further, if the temperature rise in winter is controlled to suppress the temperature rise in summer. The problem is that it cannot be secured.
Here, a part that contributes to photosynthesis and a part that does not contribute to photosynthesis and is ultimately converted into thermal energy are considered. As shown in FIG. 10, sunlight falling on the ground surface is widely distributed from an ultraviolet region near a wavelength of 350 nm to a near infrared region near a wavelength of 3000 nm. On the other hand, the wavelength band that contributes to the photosynthesis of plants varies to some extent depending on the plant, but substantially matches the ultraviolet region from about 350 nm to 750 nm to the visible light region. That is, the solar energy in the infrared region of 750 nm or more is a region that is finally converted into heat. The challenge is to suppress the rise in house temperature by preventing this area from being taken in in the summer, and to raise the house temperature by actively taking this area in the winter.
On the other hand, the black body radiation due to the temperature of the soil in the house, the structural members of the house, and the crop is mainly distributed far from 4000 nm to 12000 nm or more as shown in FIG. In the infrared region, the energy of these blackbody radiations is actively released into the outer space of the house during summer nights to reduce the temperature in the house by radiation cooling, and the energy of these blackbody radiations during winter nights. The problem is to keep warm without releasing it outside the house.

  Therefore, in the present invention, in addition to the transparent film fixedly stretched on the roof surface, another film that can be unfolded and stored on the roof surface is attached. Of the energy contained in the light, light in the visible light region that mainly contributes to photosynthesis is transmitted, so that near-infrared rays that do not contribute to photosynthesis and far-infrared energy due to black body radiation from the soil and frame members in the house are blocked. It is assumed that it has special characteristics. Then, by deploying and storing the film according to the season and day and night, the greenhouse greenhouse can be maintained at a high temperature in the winter and the house temperature in the summer can be kept low.

  It is possible to keep the house temperature in the summer low while keeping the house temperature in the winter low, so there is no need for heavy oil or electric air conditioning in the first place, or it is sufficient to operate a small one for a short time. It is possible to provide a high-performance agricultural greenhouse capable of increasing production volume and shipping at different times, and reducing facility costs and running costs.

The perspective view which installed the film winding apparatus, the 1st film, and the 2nd film on the roof surface of the flat type | mold house which is the agricultural greenhouse of the 1st Embodiment of this invention. Side view from the wife's wife Side view of the agricultural greenhouse of the second embodiment of the present invention Side view of the main part seen from the wife of the greenhouse The side view seen from the wife side of the agricultural greenhouse of the 7th Embodiment of this invention The perspective view and side view of the agricultural greenhouse of the 8th Embodiment of this invention The principal part side view of the agricultural greenhouse of the 9th Embodiment of this invention The perspective view of the agricultural greenhouse of the 10th Embodiment of this invention The side view seen from the wife side of the agricultural greenhouse of the 11th embodiment of the present invention A diagram representing the spectrum of sunlight and the spectrum that contributes to photosynthesis. Illustration of the spectrum of blackbody radiation emitted from an object with a temperature of 25 ° C.

  As a first embodiment according to the present invention, FIG. 1 shows an embodiment of a roof surface of a greenhouse called a flat-type house, in which a film is stretched flat on a metal frame. A fixed transparent first film 1 is stretched on the roof surface, and the light shielding characteristics of the first film 1 fixedly stretched are in the visible light region, the near infrared region, and the far infrared region. Use materials with good transmittance. Here, the reason why the transmittance in the visible light region is good is to allow the photosynthesis of the crops in the greenhouse to be performed well, and the reason why the transmittance in the near infrared region is good is the temperature inside the greenhouse in winter. The reason is that the near-infrared region included in the sunlight is captured in order to maintain high, and the transmittance in the far-infrared region is good because the radiation cooling in summer is effectively performed.

  On the roof surface of the greenhouse, there is installed a film winding device 3 that is generally marketed for ventilation of the greenhouse. The film winding device 3 transmits a visible light region, a near infrared region, A second film 2 having a characteristic of blocking the far infrared region is attached. FIG. 1 shows a state during development. The state which looked at this state from the vinyl house wife side is shown in FIG. In the present embodiment, the second film 2 having one end fixed to the uppermost portion (ridge portion) of the roof can be wound and stored by the film winding device 3 or can be spread over the entire roof surface. As an example of a commercially available film winding device 3, a new can kit (manual type) manufactured by Toto Kogyo Co., Ltd. or a DC motor for winding (electric type) manufactured by NI System Co., Ltd. can be used.

  As an example of the 2nd film 2 which gave the characteristic which permeate | transmits a visible region and cut | disconnects the near-infrared region and a far-infrared region, the film base material uses the vinyl chloride which has an absorption characteristic in a far-infrared region, A resin coated with a resin having a near-infrared region blocking characteristic as disclosed in JP-A-2002-370319 can be used. As another embodiment, a film base material made of vinyl chloride having absorption characteristics in the far-infrared region and a near-infrared shielding member of Patent Document 3 laminated and fixed can be used. Moreover, even if the near-infrared region blocking member has a structure that is kneaded into the film base material itself, the same effects as those coated on the surface can be obtained.

  Here, the movement of expansion and storage of the second film 2 will be described. By winding and storing the second film 2 during the daytime in the winter, all the energy contained in the sunlight is taken into the greenhouse, and during nighttime in the winter, the black body radiation is emitted from the soil and crops in the greenhouse. By blocking the far-infrared rays caused by, the temperature inside the greenhouse due to radiation cooling is prevented. The second film 2 is unfolded during the daytime in the summer to prevent the solar energy unnecessary for photosynthesis from entering the greenhouse, and it is taken up from the soil and crops in the greenhouse by being rolled up and stored during the summer. Far-infrared rays from blackbody radiation escape toward outer space and radiate cooling.

  As a second embodiment according to the present invention, a film take-up device 3 similar to that of the first embodiment is used separately from the first film 1 fixedly stretched on the roof surface as shown in FIG. A third film 4 using a material that transmits the visible light region and the far-infrared region that can be deployed and stored on the roof surface and blocks the near-infrared region is attached, and a separate film winding device 3 is installed inside the roof surface. The 4th film 5 using the material which permeate | transmits the visible-light area | region and near-infrared area | region which can be expand | deployed and can be stored, and interrupts | blocks a far-infrared area | region is attached. 4A shows a state in which the third film 4 has been unfolded about half from the state of FIG. 3, and FIG. 4B shows a state in which the fourth film 5 has almost been unfolded from the state of FIG. ing.

As the third film 4 having a property of transmitting the visible light region and blocking the near infrared region, a polyolefin resin having a low absorption rate in the far infrared region is used as the film base, and further, JP-A-2002-370319 is used. A resin coated with a resin having a near-infrared region blocking characteristic as shown in the Japanese Patent Publication No. JP-A No. 2004-26853 can be used, or a film in which a polyolefin resin is similarly used for a film base and the near-infrared blocking member of Patent Document 3 is laminated and fixed. .
Vinyl chloride can be used as the fourth film 5 that transmits the visible light region and the near infrared region and blocks the far infrared region.

Here, the movement of unfolding and storing the third film 4 and the fourth film 5 will be described.
During winter daytime, as shown in FIG. 4 a, the third film 4 is wound and stored, and the fourth film 5 is unfolded, so that energy contained in sunlight (ultraviolet, visible light, near infrared region) is increased. All are taken into the greenhouse and far infrared rays caused by black body radiation emitted from the surface of the soil and members in the greenhouse are blocked by the fourth film 5 to ensure heat insulation.
As shown in FIG. 4b, during the winter night, the third film 4 and the fourth film 5 are unfolded to cut off far-infrared rays generated by black body radiation from soil and crops in the greenhouse. By preventing the temperature in the house from decreasing and increasing the number of films, the heat conduction is reduced, so that the heat retaining property is enhanced.
During summer daytime, as shown in FIG. 4c, the third film 4 is unfolded and the fourth film 5 is wound and stored, so that only the ultraviolet region and the visible light region of sunlight are taken into the greenhouse. Far-infrared rays due to black body radiation emitted from the surface of the soil and members inside are not absorbed by the fixed and stretched roof surface first film 1 and third film 4, so that the radiation cooling effect in the direction other than the sun even in the daytime Can be issued.
As shown in FIG. 4d, the radiation cooling effect can be enhanced by winding and storing both the third film 4 and the fourth film 5 during the summer night.

As a third embodiment according to the present invention, the infrared shielding principle of the second film 2, the third film 4, and the fourth film 5 includes reflection and absorption, but a coating mainly composed of reflection is applied. Is used.
When reflecting infrared rays, there is no temperature rise in the film itself, so it is highly effective in suppressing the temperature rise during the daytime in the summer. Because the black body radiation is returned to the greenhouse as it is, the heat retention effect is high.
On the other hand, when absorbing infrared rays, the temperature of the 2nd film 2, the 3rd film 4, and the 4th film 5 itself rises. As a result, inflow of thermal energy from the second film 2 and the third film 4 outside the roof surface of the greenhouse to the inside of the greenhouse due to conduction heat occurs to some extent. Therefore, the summer daytime temperature rise suppression effect is slightly lower than the reflection. Moreover, regarding the radiant heat confinement effect in winter night, the temperature of the second film 2 and the third film 4 is almost equal to the outside air temperature, which is much higher than near absolute zero in outer space. Since it is a little lower than the temperature of the soil and members, the thermal insulation effect at night in winter is slightly lower than the reflection.
Actually, when the second film 3, the third film 4, and the fourth film 5 are manufactured, absorption and reflection of infrared rays occur simultaneously, and it is difficult to construct strictly by reflection. In the case of, a higher effect is obtained by mainly using reflection.

  As a fourth embodiment according to the present invention, as the second film 2 that can be unfolded and stored, a film that has a characteristic of transmitting the visible light region and blocking the infrared region and blocking the ultraviolet region is used. is there. By blocking the ultraviolet region, it is possible to obtain an effect of reducing diseases and insects caused by ultraviolet rays. Furthermore, by coating a member that blocks the ultraviolet region on the outside of the substrate film, the film substrate can be prevented from being deteriorated by ultraviolet rays and the effect of extending the life can be obtained. Photosynthesis also uses some light in the ultraviolet region, so the photosynthesis ability is slightly reduced, but more effects can be expected in diseases and insect damage and film life.

  In the fifth embodiment of the present invention, a film that transmits the visible light region and the far infrared region and blocks the near infrared region and blocks the ultraviolet region is used as the third film 4. This can also obtain the same effect as the fourth embodiment.

  In the sixth embodiment according to the present invention, the second film 2, the third film 4, and the fourth film 5 on the roof surface are automatically controlled. Specifically, it is possible to control it uniquely according to the season and time with an annual timer, or install sensors inside and outside the greenhouse, and more appropriate control according to the temperature inside and outside the greenhouse and the amount of solar radiation It is also possible to do. For example, if the amount of solar radiation in winter daytime is more than a certain level and the temperature inside the greenhouse is high, the second film 3, the third film 4 and the fourth film 5 are deployed, and even in the summer daytime, When the temperature is low, the second film 2, the third film 4, and the fourth film 4 on the roof surface are wound and stored. In this case, an electric type is used as the film winding device 3.

  As a seventh embodiment according to the present invention, as shown in FIG. 5, a second film 2 that can be unfolded and stored is installed on the inner side of a roof of a greenhouse. In the present embodiment, a lining film is installed on the ceiling portion in the greenhouse, and the second film 2 has a property of transmitting the visible light region and blocking the near infrared region and the far infrared region. Use film. In the present embodiment, when the temperature of the second film 2 itself rises, the heat leads to an increase in the temperature in the greenhouse. Therefore, in order to suppress the temperature rise in the daytime in summer, the principle of infrared shielding is that reflection rather than absorption. Is definitely suitable. On the other hand, the function of suppressing radiative cooling at night in winter is that the heat remains effectively in the greenhouse even when the temperature of the second film 2 itself rises. An effect can be obtained. In addition, as a mechanism for opening and closing the second film 2, a film winding device 3 similar to the first film 1 described above may be used, or a wire-type lining curtain unfolding device may be used.

  An eighth embodiment according to the present invention is shown in FIGS. 6 (a) and 6 (b). In the present embodiment, not only the roof surface of the greenhouse, but also the side surface has the same optical characteristics as the second film 2 having the characteristics of transmitting the visible light region and blocking the near infrared region and the far infrared region. Use the film 6 you have. In an ordinary greenhouse, the insect repellent net is installed on the side and the film take-up device 3 is installed on the outside to ensure ventilation. When the temperature inside the greenhouse is high, the film is taken up and the net is taken up. In this embodiment, the ventilation property is ensured. However, in this embodiment, the normal winding film itself has a light blocking property, and the film for adjusting the ventilation property is used as the film. .

  A ninth embodiment according to the present invention is shown in FIG. In the present embodiment, the film 6 having the same optical characteristics as the second film 2 according to claim 1 is applied not only to the roof surface of the greenhouse but also to the side surface, and the film of the side film 7 that is normally spread on the side surface of the greenhouse. In addition to the winding device 3, a film winding device 3 is separately installed outside the winding device 3 to develop a film 6 having the same optical characteristics as the second film 2. Moreover, the 3rd film 4 and the 4th film 5 are also applicable to each of the two film winding apparatuses 3 attached to the side surface.

  A tenth embodiment according to the present invention is shown in FIG. The present embodiment is an example in which the present invention is applied to a roof surface of a kamaboko type greenhouse called an arch pipe type. As described above, the present invention can be applied regardless of the shape of the greenhouse main body such as a flat tension type or an arch pipe type.

  An eleventh embodiment according to the present invention is shown in FIG. This embodiment is applied to the roof surface of a flat-type house to which a panel 8 in which a double film is stretched is fixed, thereby blocking both heat radiation by conduction heat and heat radiation by radiant heat, and on the roof surface during summer daytime. Even when the unfolded film itself rises in temperature due to the absorption of infrared rays, the conductive heat is not easily transmitted into the greenhouse. Also, the central top of the roof surface, the so-called ridge, has a stepped structure, and the hot air accumulated in the upper part of the greenhouse can be discharged outside the greenhouse by natural convection. With these structures, it becomes possible to keep the temperature inside the greenhouse in winter higher and to keep the temperature inside the greenhouse in summer low.

The present invention can also be applied to greenhouses other than those for agriculture.

DESCRIPTION OF SYMBOLS 1 1st film 2 2nd film 3 Film winding-up apparatus 4 3rd film 5 4th film 6 Film 7 Side film 8 Panel

Claims (10)

  A material having high transmittance in the visible light region, near infrared region and far infrared region is used as the first film fixedly stretched on the roof surface of the agricultural greenhouse, and separately from the first film, A second film that can be unfolded and stored on a roof surface is provided, and the second film uses a material that transmits the visible light region and blocks the near infrared region and the far infrared region. vinyl house.   A material having high transmittance in the visible light region, near infrared region and far infrared region is used as the first film fixedly stretched on the roof surface of the agricultural greenhouse, and separately from the first film, A third film using a material that transmits the visible and far-infrared regions that can be unfolded and stored on the roof surface and blocks the near-infrared region; and the visible-light region and the near-red that can be unfolded and stored An agricultural greenhouse comprising a fourth film made of a material that transmits an outer region and blocks the far-infrared region.   2. The agricultural greenhouse according to claim 1, wherein the infrared shielding material of the second film is mainly composed of a shielding method based on the principle of reflection.   The agricultural greenhouse according to claim 2, wherein the infrared shielding material of the third film and the fourth film is mainly composed of a shielding system based on a reflection principle.   The agricultural greenhouse according to claim 1 or 3, wherein a material that blocks an ultraviolet region in addition to the infrared region is used for the second film.   The agricultural greenhouse according to claim 2 or 4, wherein a material that blocks an ultraviolet region in addition to the near infrared region is used as the third film.   The agricultural greenhouse according to claim 1, 3, or 5, wherein the second film is automatically unfolded and stored in accordance with temperature conditions and sunlight conditions.   The agricultural greenhouse according to claim 2, 4, or 6, wherein the third film and the fourth film are automatically unfolded and stored in accordance with temperature conditions and sunlight conditions. .   The agricultural greenhouse according to claim 1, 3, 5, or 7, wherein the second film is used not only on the roof surface but also on a side surface of the agricultural greenhouse.   The said 3rd film and said 4th film were used not only on the said roof surface of the said greenhouse for agriculture but on the side surface, The claim 4, Claim 6, Claim 8 or Claim 8 characterized by the above-mentioned. Agricultural greenhouse.