JPS597852A - Reflective heat-absorbing window - Google Patents

Abstract

PURPOSE:To give a remarkable effect on energy conservation in a building through the year, by a method wherein a reflective heat-absorbing glass window in rotatably provided, solar radiations are effectively excluded in summer, and the solar radiations are effectively taken into the interior in winter. CONSTITUTION:In a light-transmitting body 41 for a composite window, a surface of a light-transmitting flat plate capable of absorbing a portion of solar radiations is treated to be capable of reflecting a part of the solar radiations, and a frame 42 for supporting and fixing the body 41 is supported by a window frame member 44 so that the frame 42 can be rotated by at least 180 deg. relatively to the frame member 44. Accordingly, solar heat can be effectively utilized in each period of the year by directing the reflection-augmented surface of the light-transmitting body 41 to the exterior to reduce cooling load in summer or in intermediate periods of cooling, and directing the surface to the interior in winter or in intermediate periods of heating.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reflective heat-absorbing window installed in an opening of a building to control solar radiation which has a strong influence on the cooling unit load of the building.

Conventionally, in order to block or control the entry of solar radiation into a room in connection with air conditioning, a metallic reflector was attached to one side of the glass, or a film with a metallic reflector attached was laminated. Radiation removal glass, radiation acquisition glass with improved transparency for solar radiation, or heat ray absorption glass that selectively absorbs near-infrared radiation from the sun and acquires solar heat by re-radiating it indoors. Alternatively, glasses with a combination of these properties have been used. However, all of these methods are only effective for either cooling or heating, and the radiation-eliminating glass used for cooling is effective in the winter, but it is rather energy-efficient as it cannot effectively introduce solar energy into the room. is a loss. Similarly, radiation acquisition glass and heat ray absorbing glass used in the winter allow more summer solar radiation to enter the room than ordinary glass, causing an increase in the cooling load. These films and glasses usually require that the amount of energy gained offsets the amount of loss, calculating the energy gain or loss over two years, and then determining whether or not there is an energy gain. The current situation is that the company has decided to adopt it. for example,
In offices, buildings, etc. in warm regions with large openings, no eaves, and air conditioning, the contribution of solar radiation to the cooling load is extremely large, often exceeding the solar heat removal loss during the heating season. However, this is not necessarily true for buildings located in relatively cold regions or homes where heating is more important than air conditioning. That is, the range of application of various films and glasses according to the prior art is relatively limited.

However, in recent years, the need for energy conservation in buildings has been emphasized, and along with building insulation, the power of window openings has increased.

There is currently a strong demand for the development of window opening members that have both the functions of actively acquiring solar heat in the winter and removing radiant heat in the summer.

The present invention was developed against the background of these current circumstances, and is an all-season energy-saving type that uses a rotatable reflective and heat-absorbing glass window and can be easily changed from front to back to the indoor side in summer and winter. The purpose is to provide a window.

An embodiment of the present invention will be described below with reference to the drawings. Figure 1 is a side cross-sectional view of a composite core transparent material that is the main element constituting the reflective heat-absorbing window of the present invention. A reflection-enhancing layer 2 is attached to one surface of a light-transmitting flat plate 1 such as glass, which has been subjected to a reflection treatment.In order to enhance the absorption rate of glass, an arbitrary method can be applied by introducing a known metal element. Solar radiation absorption rate can be obtained. Particularly in carrying out the present invention, it is desirable to use a glass that has higher near-infrared absorption than visible light absorption, and for that purpose, it is recommended to use iron or the like as the metal element. Various known methods can be used for the reflection treatment on one side of the transparent plate 1, such as glass. For example, metals such as aluminum and copper can be deposited as a thin film by vapor deposition, sintering, plating, etc. In this method, a thin metal film is bonded to a polymer film and coated with a protective coating such as a resin, or a thin metal film is bonded to a polymer film using a similar method, and the metal thin film is bonded to one surface of a glass or the like. In either case, the reflectance can be selected relatively arbitrarily. However, there is a certain relationship between the above-mentioned selection of absorptance and reflectance and the resulting energy saving, as will be described later. % or more in relation to the light transmittance into the room.

FIGS. 2 and 3 are diagrams illustrating the reflection/absorption characteristics of the composite core transmissive body when the solar radiation incident surface is the reflection enhancing surface and when the opposite surface is the reflection enhancing surface, respectively.

The branching arrows shown in the figure schematically show each component of the radiation that is removed outdoors and the radiation that is transmitted indoors due to the balance between solar radiation and the absorption rate and reflectance of the composite core transparent material. It is. Although back reflections and higher-order internal reflections are not shown to simplify the drawing, it is clear that the principles of the present invention do not lose their generality due to this simplification.

In Fig. 2, when solar radiation 3 enters from the reflection-enhancing surface 2, the reflected component 4 is first removed to the outside according to the reflectance of the reflection-enhancing surface 2, while the remaining radiation components are After penetrating through the glass and receiving absorption corresponding to the absorption rate of the glass, it is acquired into the room as a transmitted component 6. The radiant components absorbed during this period are conducted through the light-transmitting plate 1 such as glass, increasing its temperature, and as a result, the heat is radiated indoors and outdoors as heat radiating components. The ratio of indoor heat radiation 6 to outdoor heat radiation 7 has different values depending on the indoor and outdoor temperature and humidity, and the amount of sky radiation.

The ratio of the energy component, which is the sum of the reflected component 4 and the outdoor component 7 of absorption and conduction heat radiation, to the incident component 3 is the solar radiation removal rate, and the ratio of the energy component, which is the sum of the transmitted component 5 and the indoor heat radiation component 6, to the incident component 3 is the solar radiation. This is sometimes called total transmittance, and here they are simply described as removal rate and total transmittance, respectively, to distinguish it from the normally used transmittance in which only the transmitted component 5 is considered.

Figure 3 shows the case where solar radiation is incident on the opposite surfaces of the reflection enhancement diagram 2. The incident solar radiation 3 is absorbed and conducted by the transparent flat plate 1, and is conducted to the indoor side and the outdoor side, respectively. Heat is radiated as heat radiation component 9.10. The remaining radiation is reflected by the reflection-enhancing surface 2 in accordance with the reflectance, but a part of the radiation component is absorbed again while passing through the glass 1 and is conducted into the room.

Heat is radiated into the room as conduction heat radiation components 11 and 12, respectively. The remainder is removed to the outside as a reflected component 8. On the other hand, the remaining radiation that is not reflected by the reflection-enhancing surface 2 is acquired into the room as a transmitted component 5. Therefore, the removal rate in this case is the sum of the reflection component 8 and the conduction heat radiation components 10 and 12, and the total transmittance is the sum of the transmission component 5 and the conduction heat radiation components 9 and 11.

As can be qualitatively understood from the explanations and diagrams in Figures 2 and 3, the incidence state in Figure 2 (has a higher removal rate than that in Figure 3), and the incidence state in Figure 3 The total transmittance into the room is larger than that shown in Figure 2. Therefore, in order to reduce the cooling load in the summer or mid-air cooling period, the composite window transmissive material should be used with the reflection-enhancing surface 2 facing the outdoor side. It will be understood that if the reflection-enhancing surface 2 is directed toward the indoor side during each season, the solar heat can be utilized very effectively during each season.

FIG. 4 shows an embodiment of a reflective heat-absorbing window in which such a composite window glass is used as a specific window member as described above. In the figure, numeral 41 denotes the above-mentioned reflective/endothermic composite window transmissive body, and numeral 42 denotes a frame for supporting and fixing it. The frame 42 is rotatably supported by at least 180° relative to the window frame material 44 at the intersection with a rotating shaft 43 along the surface of the transparent body so that the front and back sides of the composite window transparent body 410 can be changed in summer and winter. With this configuration, the frame 42 can be rotated 42 times so that the reflection-enhancing surface faces outward in summer and inward in winter, and the frame 42 can be fixed to the window frame material 44 using the holes, rips 46, 46', etc. .

Next, the relationship between the related physical quantities of the composite window transparent body and the energy saving effect will be explained with reference to the characteristic diagram shown in FIG. 5. FIG. 5 shows various changes in the transmittance and reflectance of the reflection-enhancing surface when glass is used as the base material of the composite window transmissive body of the present invention.
The increase in the total solar radiation transmittance of the composite core transmittance during the winter season with respect to the front and back sides is expressed as a percentage, assuming that the energy saving is one time. In other words, here, the term "one-time energy saving" refers to when the glass is used as a reflective glass in the same way as the conventional method in the summer, that is, when the reflection-enhancing surface is used on the outside, and when it is left in that state in the winter, and when the method of the present invention is used as a reflective glass. In the winter, the increase in total transmittance related to the amount of solar radiation entering the room when the reflection-enhancing surface is rotated inward is shown as a percentage.In the figure, the horizontal axis A is the absorption rate of the glass. is expressed as a percentage, B indicates the energy saving degree mentioned above, and curves 1D to 6
Corresponds to D. C indicates the reflectance of the corresponding reflection-enhancing surface in percentage and corresponds to curves 1E to 6E.

In addition, iD and IE are 2 if the transmittance of the composite window glass (corresponding to the transmitted component 5 in Figures 2 and 3) is 30%
This is the characteristic curve when D and 2E are 36%, 3D and 3E are 4o%, 4D and 4 are 45%, 5D and 5 are 50%, and eD and eE are 55% ○ It is clear from Figure 5 As such, in the present invention, the absorption rate,
Transmittance and reflectance are not independent and arbitrary but have a constant relationship, and for example, there is an absorption rate at which energy saving is optimal once for various values of transmittance. In addition, as mentioned above, the characteristics shown in the figure indicate energy savings under standard conditions in the winter, so in order to expect a large effect in the summer, it is advantageous to select a larger value for the reflectance. In addition, these word values are constrained by conditions arising from the original function of windows in practical life.

For example, this is a condition where, although the purpose is to improve energy saving, it is undesirable to significantly reduce transmittance in terms of brightness and the like.

The optimal ranges of absorption and reflectance for effectively carrying out the present invention will be explained below based on the limit values under these various conditions.

It is recommended that the energy saving is at least 6% or more in consideration of the increase in material investment in the present invention. Also, visually, it is better to suppress the transmittance to a certain extent to prevent glare from the outside world [m is comfortable, but visually it is desirable to maintain a transmittance of at least 30%. . On the other hand, the reflectance against solar radiation should be at least 20% to ensure the radiation removal effect in summer.
It is recommended that the above is set.

Taking these conditions into account, it is recommended that the solar radiation absorption rate A of the composite window transmissive body is in the range of at least 10% to 50%, as shown in FIG.

Another embodiment that makes the present invention even more effective is shown in FIG. In the figure, numerals 1 and 2 indicate the absorbent glass and the reflection enhancing layer, respectively, which have been explained above. A light-transmitting flat plate such as ordinary transparent glass 62 is attached to the frame 42 and window frame material 44 shown in FIG. As in the previous example, the reflection-enhancing surface 2 is used on the outside of the room in the summer and on the inside of the room in the winter.

The salient feature of this example is that it is intended not only to enhance the summer and winter effects of the present invention, but also to reduce the heat flow rate and improve the sound insulation properties of double glazing, commonly known as double glazing. The reason for increasing the effects in summer and winter will be clear from the following explanation.One of the requirements of this example is to increase the absorption rate of the transparent flat plate of the composite window transparent body compared to normal. In this respect, the temperature of the composite window transparent material itself increases compared to normal glass, so
Therefore, in the summer when this composite window transparent body is located outside the room, heat transfer from this composite window transparent body to the outside increases, and as a result, the solar radiation removal rate is increased. On the other hand, in winter, from the operation of the present invention described above, considering that the composite window transparent body is on the indoor side and has a higher temperature than normal glass, and that the temperature of the void 61 is higher than the outside temperature,
The total transmittance of solar radiation into the room is significantly greater than when using a single composite window transmissive body. In this way, the effects of this embodiment are a reduction in heat loss due to a reduction in heat flow rate, and
This has a remarkable effect not only in improving the sound insulation properties but also in improving the energy saving of the present invention.

Although the above embodiments have been described using specific materials and configurations for understanding aspects of the present invention, other materials or configurations having similar functions or different combinations may be used in practice.

For example, the composite window transmissive body is not necessarily limited to glass, and the present invention can also be implemented using synthetic resin materials such as acrylic and polycarbonate. Reflective heat-absorbing windows, which are rotatably formed with a compound window transparent body that has been subjected to reflective treatment on one side of an absorbing light-transmitting flat plate, effectively remove solar radiation in the summer and during the cooling period, while being effective in the winter and during the heating period. has a remarkable effect on building energy savings over the year by effectively capturing solar radiation indoors.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional side view showing an example of the composite window transmissive body used in the present invention, and Figs. 2 and 3 are explanatory diagrams of the reflection/absorption characteristics of the composite window transmissive body shown in Fig. 1. , FIG. 4 is a perspective view showing an embodiment of the reflective heat-absorbing window according to the present invention, FIG. 5 is a characteristic diagram of the reflective heat-absorbing window according to the present invention, and FIG. 6 is a perspective view showing an embodiment of the reflective heat-absorbing window according to the present invention. 0 is a cross-sectional side view showing an example of
1... Translucent flat plate, 2... Reflection enhancing layer, 4
1...Composite window translucent body, 42...Frame, 4
4...Window frame material, 61...Gap, 62...
・Translucent board 0 Name of agent: Patent attorney Toshio Nakao and one other person Figure 1 Figure 4 Figure 3

Claims (3)

[Claims] (1) A composite window transparent body in which one surface of a transparent flat plate that absorbs a portion of solar radiation is treated to reflect a portion of solar radiation;
A reflective heat-absorbing window comprising a frame for supporting and fixing the composite window transparent body, and a window frame member for supporting the frame, wherein the frame is rotatable at least 1800 degrees with respect to the window frame member. (2) The solar radiation absorption rate of the transparent flat plate is 10% to 6o%
2. The reflective heat-absorbing window according to claim 1, wherein the reflection-treated surface has a solar radiation reflectance of 20% or more. (3) On the non-reflective side of the composite window transparent material,
A reflective phosphor nitride according to claim 1, wherein a structure in which solar radiation-transmitting flat plates are arranged with gaps in parallel with the surface of the composite window transparent body is supported and fixed to a frame.