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Features and applications of magnetically controlled roll-film insulating glass

The existing various types of conventional insulating glass, once the production process is completed, the relevant performance indicators such as light transmittance and shading coefficient are fixed. These conventional insulating glass, which belongs to static control performance, are used as doors and windows or curtain wall glass for construction to face the ever-changing natural environment, and there will be many shortcomings.

To better solve these problems, there are three development directions: one is to add various accessories on the inner and outer sides of the hollow glass doors and windows for energy saving or dimmings, such as outdoor sun visors and sunshades, and various indoor curtain. The second is to add various adjustable curtains in the hollow glass, such as Venetian blinds and pleated blinds. The third is to make functional glass with adjustable properties, such as photochromic, thermochromic, and electrochromic glass into the hollow glass.

Judging from the current market conditions, the first method has a very long history of use and has been widely used. Although these structures have many characteristics, it has become increasingly difficult to meet the needs of modern life. Due to the non-standard structure, the second method has a high cost, low reliability, and limited market promotion and acceptance. The third method can be said to be the development direction of architectural glass, but it cannot be promoted and applied at least due to cost and other reasons.

The Magnetron Rolled Film Type Insulating Glass is a product with "new functions". Its basic structure belongs to the second form, and its function is just between the second and the third. It not only retains the advantages of both but also avoids their shortcomings. In the future, it will become the main development form of energy-saving and dimming of insulating glass.

Figure 1 The magnetically controlled roll-film insulating glass 1

Figure 1 The magnetically controlled roll-film insulating glass 1

The basic structure and control form of magnetically controlled roll-film insulating glass

The magnetron roll film type insulating glass is mainly composed of conventional hollow glass and magnetron roll film components (mainly including magnetic non-contact transmission control structure, film winding drive mechanism, and various polyester-based selective light transmission functions Film) consists of two parts.

The assembled magnetron film module is enclosed in the conventional insulating glass, and the power is input through the magnetic non-contact transmission system outside the conventional insulating glass to drive the expansion or contraction of the film with different selective light transmission functions inside the conventional hollow glass. To achieve the purpose of controlling the heat insulation or dimming function of conventional insulating glass.

When working, when the outer magnetic body outside the conventional insulating glass is rotated by pulling the zipper outside the conventional insulating glass or the motor is used to drive the outer magnetic body outside the conventional insulating glass, the magnetic non-contact transmission system directly drives the inner magnet sealed inside the conventional insulating glass to rotate, and at the same time drives the fixation. The reel outside the inner magnet rotates to achieve the purpose of shrinking or unwinding the film.

The magnetron roll film module is mainly designed for the existing conventional insulating glass, without changing the existing conventional insulating glass production process, without changing the inner and outer dimensions of the existing conventional insulating glass, and without changing the installation and fixing of the existing conventional insulating glass profiles. It does not increase the adjustment range of conventional insulating glass in terms of heat insulation, light transmission, and sight shielding.

The magnetron roll film module has a simple structure and can be installed in various rectangular plane conventional insulating glass with an internal gap greater than 6 mm. The thickness of the film, the diameter of the reel, and the diameter of the magnetic body in the reel are restricted in the control film component.

Because the magnetic levitation technology is also used in the magnetically controlled roll-film insulating glass, the slender reel is in a straight state during operation and the need for large-size conventional insulating glass is ensured.

Among the many key structures of the magnetically controlled roll-film insulating glass, after domestic and foreign patent searches and market surveys, no similar products or structures have been found. At present, these technologies or basic structures have been applied for Chinese invention patents and have been approved. It has also applied for U.S. and European patents, among which U.S. patents have been published.

When the external magnetic parts are driven by a motor, various remote control, group control, and intelligent control can be easily realized through different control methods, which can better meet the basic requirements of modern buildings for building glass in terms of intelligence.

In addition, since the roll film is made of polyester film as the base material, it has excellent anti-aging properties. At the same time, all power sources are outside the conventional hollow glass, and the inner rotating shaft of the conventional hollow glass is driven to rotate by a magnetic field without any intermediate transmission parts so that the system has good interchangeability and high reliability.

Since this product does not have national standards or other related standards, to ensure the production and quality of magnetron-rolled insulating glass products, Legolas is responsible for the production and inspection standards of the "Magnetic-controlled Rolled Film for Insulating Glass". , It was formally approved by Chinese National Municipal Quality and Technical Supervision Bureau and implemented as an enterprise standard.

We sent the magnetron-rolled insulating glass sample to Chinese National Product Quality Supervision and Inspection Institute for testing. After 100,000 continuous windings, the film and the entire magnetic non-contact transmission mechanism have no failure or damage. If the average rolling film cycle is counted three times per day, it can work for 100 years without damage, and its working life is much longer than the sealing working life of any existing insulating glass.

The magnetron roll film type insulating glass-related performance analysis

When doing the following analysis, first assume two basic conditions:

(1) The production process and technical requirements of the hollow glass equipped with the magnetron roll film module are the same as those of the conventional hollow glass.

(2) The insulating glass equipped with the magnetron roll film module is the same as the glass material used in the conventional insulating glass.

1. Performance analysis of magnetron-rolled insulating glass under different working conditions  

The working state of the magnetically controlled roll film type insulating glass can be roughly divided into three extreme states: 

(1) The roll film is fully wound. 

(2) The roll film is fully unfolded. 

(3) The roll film is in a half-unfolded state.

In the first state, the film is fully rolled up. It can be considered that its related thermal insulation performance is the same as that of conventional insulating glass.

In the second roll film fully unfolded state, it is the same as the hollow glass with a fixed film added between the two glass gaps in the conventional hollow glass. For example, the Southwall Technology Company of the United States produces a thin film called Heat Mirror, which is used to sandwich between insulating glass. According to the test data released by the company, in the hollow glass made of various glass, when different types of films are clamped, the relevant data of the entire block of hollow glass such as transmittance, reflectance, and glass before and after the film is clamped. U value, shading coefficient, ultraviolet transmittance, etc. have all changed greatly, which proves that adding a layer of film in the middle of the hollow glass can effectively change the basic performance of the whole hollow glass.

In terms of heat insulation, convection, and conduction, because there is a certain gap between the periphery of the unrolled film and the inner space of the hollow glass, there will be a certain convection heat loss when there is a temperature difference, so the performance in this aspect is lower than the formation of the internal clamp fixed-film. Insulating glass with two enclosed spaces is better than conventional insulating glass.

In the third state, the roll film is in an intermediate state. For the whole piece of conventional insulating glass, the heat insulation performance of the part that is not covered by the roll film is the same as that of conventional insulating glass, and the part covered by the roll film is the same as the fixed laminated insulating glass in terms of blocking heat insulation radiation, but in blocking convection conduction. In terms of it, it can be considered as basically the same as conventional insulating glass.

2. Performance analysis of various roll film materials combined with various conventional insulating glass  

The combination of various roll film materials and various conventional insulating glass.

The actual effects of the above combinations are discussed separately as follows.

(1) The transparent insulating glass + different roll film

The characteristic of this kind of combination is that it can use low-cost transparent insulating glass, which can have strong heat insulation or dimming effect after being loaded with different roll films. It has an obvious two-way adjustment effect on solar energy when the film is rolled up or fully unfolded.

(1-1) roll film is the matte film  

The characteristic of the matt film is that it is transparent and opaque, and has little effect on blocking heat and radiation, but it is very effective in blocking the line of sight and protecting privacy.

(1-2) roll film is heat reflective film 

The characteristic of heat reflection is that the shading coefficient is small, and the cost is also low. The roll film is unrolled in summer for shading, and the roll film is folded in winter to transmit sunlight for heating, which has a good overall energy-saving effect throughout the year.

(1-3) Roll film is the heat-absorbing film (color film)  

The color type and color depth of this roll film can have a lot of choices, so there is a considerable range of changes in the shading coefficient and light transmittance, and specific designs can be made according to the different requirements of users.

(1-4) roll film is Low-E film   

This is a very ideal combination because it can have better lighting and heat insulation compatibility. When there is sunlight in winter, the film rolls up and can transmit most of the solar heat radiation; when there is no sunlight, the film rolls out to prevent the loss of indoor long-wave thermal radiation. When there is sunshine in summer, the roll film can be opened to block most of the heat radiation from entering the room; at night, when the indoor temperature is higher than the outdoor temperature, the roll film can be folded to dissipate the indoor heat radiation. Its comprehensive energy-saving effect throughout the year is better than that of heat-reflective film, and it has obvious two-way energy-saving and dimming functions.

(2) heat-reflective insulating glass + different roll film

The characteristics of this type of combination are: because the heat reflective glass itself has a low light transmittance and shading coefficient, plus the heat reflective film or the heat absorption film is of little significance, and the adjustment effect after adding other films is not obvious...

(2-1) roll film is the matte film

The main function: after unfolding is to block the line of sight.

(2-2) roll film is Low-E film

After unfolding, the heat insulation effect of the entire glass can be further improved.

(3) heat-absorbing insulating glass + different roll film 

The characteristics of this type of combination are similar to the effect of the above-mentioned heat-reflective insulating glass + different roll film combinations.

(4) Low-E insulating glass + different roll film  

The characteristics of this type of combination are: using the characteristics of Low-E insulating glass, coupled with different functions of the film, can further enhance the relevant functions of Low-E insulating glass, and it is a kind of combination that is worth popularizing.

(4-1) roll film is the matte film

Low-E insulating glass is characterized by high light transmittance. After unfolding the matte film, the light transmittance can be reduced, so that direct light becomes diffuse light, and it can block the line of sight. It is quite ideal combination.

(4-2) roll film is heat reflective film

At present, hollow glass made of Low-E coated glass and heat-reflective coated glass has good application examples. It can not only shield the radiant heat of the sun but also has an extremely low heat transfer coefficient. A more realistic combination. It is also a feasible combination to use heat-reflective film instead of heat-reflective coated glass and Low-E coated glass to form hollow glass.

(4-3) Roll film is the heat-absorbing film (color film)

This combination still has certain uses on some special needs occasions. For example, many occasions need to be kept dark during the day. The use of this roll film is a layer of blackout curtains. Low-E film is blocked, so  will be no overheating problem even with black film.

(4-4) roll film is another Low-E film 

The combination can be coated with winter Low-E coating on the outer and inner surface of the insulating glass, and the roll film can be coated with a sun-shading Low-E coating, making it an all-round Low-E insulating glass that can be applied in winter or summer.

From the above analysis, it can be seen that there are various combinations of various roll film materials and various conventional insulating glass. In the specific use, it should be selected according to the environment.

Specific application design features and usage methods

Architectural glass generally provides visual transparency or daylighting, and at the same time, it should also have the function of adjusting the radiant energy passed into or out of the building, to achieve a comfortable indoor thermal environment with the lowest possible energy consumption. It is necessary to take into account various factors such as appearance and cost, which are also some basic principles for designing and adopting architectural glass.

From the perspective of heat insulation and energy-saving, according to the International  Building Thermal Design Standards, the country is divided into five building thermal design zones, including severe cold areas, cold areas, hot summer, and cold winter areas, and hot summer and warm winter. Regions and warm regions. In these different areas, climate change and the different orientations of specific buildings have different requirements for heat insulation of doors and windows. If conventional insulating glass with static control performance is used, it is difficult to meet some or even contradictory requirements at the same time. However, if the magnetically controlled roll-film insulating glass is used and the dynamic adjustment function of roll-film is fully utilized, better heat insulation and energy-saving effects will be obtained.

In severe cold and cold areas, the common characteristics are long winters, large annual temperature differences, and large solar radiation. Building heating energy consumption in these areas is high.

There are two main almost contradictory requirements for conventional insulating glass : 

(1) Let as much solar heat radiation as possible enter the room, 

(2) The effectively prevent indoor heat from being lost to the outdoors through radiation. 

To meet the above requirements at the same time, it is recommended to use ordinary transparent insulating glass with Low-E film or heat reflective film as the main structure. When there is sunlight, the film rolls up so that ordinary transparent insulating glass can pass most of the heat radiation. When there is no sunlight, the film rolls out to effectively prevent the long-wave heat radiation in the room from dissipating.

In the Middle and high latitudes of the Northern Hemisphere areas, it is characterized by hot summers and cold winters. With the improvement of living standards, the cost of cooling is higher than the cost of heating in terms of building energy consumption. Correspondingly, the use of conventional insulating glass should take into account both solar radiation transmission and shading, and highlight the shading function. When choosing magnetically controlled roll-film insulating glass, it should be selected according to the actual local climate conditions and the specific orientation of the building. At this time, the transparent insulating glass is equipped with Low-E film or heat reflective film, and Low-E insulating glass is equipped with Low-E. Combinations such as film or heat-reflective film are better choices.

For example, taking the Middle and high latitudes of the Northern Hemisphere Area as an example, through simulation calculations, it is proved that the shading coefficient of conventional insulating glass has a great influence on the total energy consumption of the building throughout the year. When the shading coefficient is large, the energy consumption in winter decreases but the energy consumption increases in summer, resulting in an increase in the total energy consumption throughout the year. In this environment, if a magnetically controlled roll-film insulating glass with a low shading coefficient is used, through dynamic adjustment control and changing the shading coefficient, a significant annual comprehensive energy-saving effect can be obtained compared to the conventional hollow glass with static control function.

In areas with hot summers and warm winters, which are characterized by long periods of high temperature and strong solar radiation, building energy consumption is mainly refrigeration, and building glass should also take sunshade as its main function. In this area, it is recommended to use Low-E hollow glass with various functional roll films, which can achieve better results while taking into account the requirements of energy-saving and daylighting.

For example, in most southern hot areas, high-transmittance solar control Low-E insulating glass with matt roll film can be used as door and window or curtain wall glass. The light transmittance of the entire Low-E insulating glass is 70%. The light transmittance is 75%. When the film is exposed to direct sunlight, the visible light transmittance can be reduced to about 50% when the film is unrolled, and at the same time, the direct light becomes diffuse light, which has suitable lighting and visual comfort. When it rains on a cloudy day and there is no direct sunlight, close the roll film to obtain sufficient lighting. In addition, the characteristic of the matt roll film is light transmission and opacity, no matter day or night, it has a good effect of blocking the line of sight, and at the same time does not damage or affect the appearance and decoration of the curtain wall glass. This combination should be a way worth promoting.

From the perspective of lighting and blocking sight, another important contribution of magnetron roll-film insulating glass to modern architecture is to provide more comfort options. Taking indoor lighting as an example, in the face of climate and illumination changes in the four seasons of the year and 24 hours a day in nature, the existing conventional insulating glass with various static control functions has a very narrow adaptation range. To overcome these defects, it has to be supplemented by installing various adjustable curtains and other devices indoors and outdoors. The magnetron roll-film insulating glass has two extreme states (the roll film is fully retracted and fully unfolded) and a variety of intermediate states, which have a large range of adaptation and adjustment to lighting.

Figure 2 The magnetically controlled roll-film insulating glass 2

When magnetron roll-film insulating glass is used as door and window glass, through different choices of conventional insulating glass and roll-film, while taking into account the requirements of building energy conservation, there can be more solutions to control the shielding of outdoor sightlines. For example, the roll film can be a single-reflection film or a heat-reflecting film with a light transmittance of less than 30%, a heat-absorbing film (color film), a matte film, a variety of patterned films, etc., which can better meet the outdoor line of sight after unrolling. sexual demands. From the perspective of performance and effects, the magnetron roll film insulating glass can cancel the internal and external sunshade devices to a considerable extent, especially the various indoor curtains.

When the magnetron roll film insulating glass is used as curtain wall glass, the exterior appearance is the first for the curtain wall glass, and the light shielding and heat insulation properties should be highlighted without affecting the appearance. At this time, light gray frosted or another similar roll film can be used to improve sight blocking and improve the consistency of the appearance of curtain wall glass.

The roll film of the magnetron roll-film insulating glass is flatly unfolded inside the insulating glass. Compared with ordinary curtains hanging outside the glass, its appearance is better, and at the same time, it avoids the trouble of cleaning the external curtains. It is very suitable for hospitals, Some public places with high hygiene requirements, such as schools and food factories.

In addition to the characteristics of simple structure, high reliability, strong anti-aging, and durability, magnetron film-rolled insulating glass itself, compared with conventional insulating glass, the most prominent is its manual or electric two-way dynamic adjustment function, with Good heat insulation, energy-saving, lighting, and blocking sight characteristics provide a wider space for modern buildings and users in the use and selection of architectural glass.


For more information about Jinan LIJIANG Glass insulating glass processing equipment and insulating glass processing accessories, please click here to learn more. 

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