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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 insulating glass doors and windows for energy saving or dimmings, such as outdoor sun visors and sunshades curtains, 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 insulating 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 at least it cannot be promoted and applied due to cost and other reasons.

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.

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

Magnetron roll film type insulating glass is mainly composed of conventional hollow glass and magnetron roll film components (mainly include: magnetic non-contact transmission control structure, film winding drive mechanism, 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 insulating 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. It does not change the existing conventional insulating glass production process, does not change the inner and outer dimensions of the existing conventional insulating glass, and does not change the installation and fixation 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 flat conventional hollow glass with an internal gap greater than 6 mm. Due to the limitation of the internal gap of the conventional hollow glass, the unfolding length of the roll film in the conventional hollow glass is mainly affected by magnetism. 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, through different control methods, various remote control, group control, and intelligent control can be easily realized, 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 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 extremely high reliability.

Since this product does not have relevant national standards or other relevant standards, to ensure the production and quality of magnetically controlled roll-film insulating glass products, the company is responsible for the production and inspection of the "Magnetic Controlled Rolling Film for Insulating Glass" formulated by Legends The standard was formally approved by the China Quality and Technical Supervision Bureau.

Jinan LIJIANG Glass will send the magnetron-rolled insulating glass samples produced by the Jinan LIJIANG insulating glass production line to the China Product Quality Supervision and Inspection Institute for testing. After continuous winding of 100,000 times, the film and the entire magnetic non-contact transmission mechanism have no faults or damage. If the average rolling film cycle is counted three times a 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.

Figure 1 The Jinan LIJIANG insulating glass production line

Figure 1 The Jinan LIJIANG insulating glass production line 

Magnetic control 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 that of the conventional hollow glass.

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

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 wound. 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 HeatMirror, 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 that of the internal clamp 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 hollow 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. On the one hand, it can be considered that it is 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) transparent insulating glass + different roll film

The characteristic of this type 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. When the film is rolled up or fully unfolded, it has an obvious two-way adjustment effect on solar energy.

(1-1) roll film is the matte film  

The sub-light film is characterized by light transmission and opacity. It has little effect on blocking heat and radiation, but it has a good effect on 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 low light transmittance and shading coefficient, plus the heat reflective film or 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 improve the relevant functions of Low-E insulating glass, is a kind of combination that is worthy of promotion.

(4-1) roll film is the matte film   

Low-E hollow 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 an ideal combination method.

(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 a very 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 occasions with special needs. For example, many occasions need to be kept dark during the day. The use of this roll film is a layer of blackout curtains. -E film is blocked, so there will be no overheating problem even with black film.

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

This combination can be coated with winter Low-E coating on the outer 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 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, while 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, the United States is divided into five thermal design areas for buildings, including severe cold areas, cold areas, hot summer, and cold winter areas, hot summer and warm winter areas, and warm areas. 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 the roll film is fully utilized, it will be able to obtain better heat insulation and energy-saving effects.

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 the 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 from being lost indoors.

In hot summer and cold winter areas, 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 the 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 New York area of the United States 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 the magnetically controlled roll-film insulating glass with a low shading coefficient is adopted, through dynamic adjustment control and changing the shading coefficient, it can obtain an obvious comprehensive energy-saving effect throughout the year when compared with 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 architectural glass should also use sun shading as its main function. In this area, it is recommended to use Low-E insulating 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%, and the matte film 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 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 matt film is characterized by light transmission and opacity, which has a good effect of blocking the line of sight regardless of day and night, and at the same time does not damage or affect the appearance of the curtain wall glass. This combination should be a way worth promoting.

From the perspective of daylighting and obstructing the line of sight, another important contribution of magnetically controlled roll-film insulating glass to modern architecture is to provide more comfort options. Taking indoor lighting as an example, in the face of changes in climate and light in nature throughout the year and 24 hours a day, the existing conventional insulating glass with various static control functions has a rather narrow adaptation range. To overcome these shortcomings, it had to be supplemented by installing various adjustable curtains and other devices indoors and outdoors. However, the magnetically controlled roll-film insulating glass has two extreme states (the roll film is fully folded and fully expanded) and a variety of intermediate states, which have a larger range of adaptation and adjustment for lighting.

When the magnetically controlled 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-saving, there can be more solutions in controlling the outdoor sight shielding. For example, the roll film can use a single reflective film or a heat reflective film with a light transmittance of less than 30%, a heat absorption film (color film), a matte film, various patterned films, etc., which can better meet the outdoor sight shielding after unfolding Sexual requirements. From the perspective of performance and effects, the magnetically controlled roll-film insulating glass can eliminate internal and external sun-shading devices to a considerable extent, especially the various indoor curtains.

When the magnetically controlled roll-film insulating glass is used as curtain wall glass, the appearance of the curtain wall glass is the first, and it should highlight the visibility and heat insulation without affecting the appearance. At this time, light gray frosted or other similar rolled film can be used to improve the visibility of the line of sight and improve the consistency of the appearance of the curtain wall glass.

The roll film of the magnetically controlled roll film type hollow glass is flatly unfolded inside the hollow glass. Compared with the ordinary curtains hanging on the outside of the glass, its appearance effect is better, and it avoids the trouble of cleaning the external curtains. It is very suitable for hospitals Schools, food factories, and other public places with high hygiene requirements.

In addition to the characteristics of simple structure, high reliability, strong aging resistance, and durability, the magnetically controlled roll-film insulating glass itself, compared with conventional insulating glass, the most prominent is its manual or electric two-way dynamic adjustment function. Good heat insulation, energy-saving, daylighting, and line of sight blocking 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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