Sunshade net capable of automatically adjusting light transmittance

Abstract

The invention relates to the technical field of sunshade net structures, in particular to a sunshade net capable of automatically adjusting light transmittance, which comprises a sunshade net body, and the sunshade net body is in two forms of weaving thermoplastic shape memory lines or integrally forming a net; the sunshade net body is made of a temperature-sensitive composite material, the temperature-sensitive composite material has a shape memory effect and a thermochromic effect, and the temperature-sensitive composite material comprises a composite body of a thermoplastic shape memory polymer and a thermochromic material; by utilizing the characteristics of the thermoplastic shape memory polymer and the thermochromic material composite material, the sunshade net can automatically adjust the light transmittance at lt according to the environment temperature change; at the normal temperature or low temperature of 25 DEG C, the meshes are in an initial fixed state, the sunshade net body is colorless, and the light transmission is high, so that lighting and temperature rising are promoted; at high temperature gt; when the temperature is 25 DEG C, the meshes become smaller, the color of the sunshade net body becomes darker, and light transmission is reduced so as to lower the temperature.

Description

Technical Field

[0001] This invention relates to the field of shade net structure technology, and in particular to a shade net that can automatically adjust light transmittance. Background Technology

[0002] Shade nets, widely used in agriculture, construction, and outdoor recreation, primarily function to block or reduce excessive solar radiation to achieve cooling, sun protection, and protection for people, animals, plants, or equipment. Currently, most mainstream shade net products on the market have a static design, meaning that the density, size, and shape of the mesh, as well as the material's color and reflectivity—the core optical and physical parameters—are fixed after manufacturing.

[0003] This static characteristic determines the singularity and non-adjustability of its performance, which exposes significant limitations in practical applications, especially when dealing with complex, changeable, and dynamically fluctuating weather conditions, where its drawbacks are even more prominent. When the ambient light intensity and heat are low, static shade nets will still maintain their inherent high shading rate, excessively blocking precious natural light. For agricultural greenhouses, this will lead to insufficient effective photosynthesis of crops inside the greenhouse, which will not only affect the normal growth and development of plants and prolong their growth cycle, but may also lead to reduced crop yield and decreased quality due to long-term low temperature and low light, forming a negative shading effect. For indoor spaces or outdoor facilities that require lighting and heat preservation, static shade nets will also cause unnecessary indoor darkness and heat loss. When solar radiation intensity increases sharply, static shade nets with a fixed shading rate may be inadequate, as their shading capacity is insufficient to cope with extreme heat loads. Excessive infrared and ultraviolet rays penetrating the shade net can lead to excessively high microenvironment temperatures under its coverage. In agricultural settings, this can easily cause problems such as leaf burn, fruit sunburn, and excessively rapid evaporation of soil moisture.

[0004] Therefore, it is evident that traditional static shade nets can no longer meet the needs of most scenarios. Existing static shade nets typically have a shading rate as high as 70-80%, making them unsuitable for use in low light intensity environments. On the other hand, static shading materials with high light transmittance, such as thermoplastic polyurethane used alone, are suitable for use in low light intensity scenarios, but cannot meet the requirements for reducing light transmittance and providing shading in high light intensity scenarios. Therefore, a shade net that can automatically adjust light transmittance is needed to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to solve the problems mentioned in the background section.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A shading net capable of automatically adjusting light transmittance includes a shading net body, which can be formed by either woven thermoplastic shape memory yarn or a one-piece molded net. The shading net body is made of a temperature-sensitive composite material, which possesses both shape memory and thermochromic effects. The temperature-sensitive composite material is a composite of a thermoplastic shape memory polymer and a thermochromic material. The temperature-sensitive composite material is key to achieving automatic adjustment. The shape memory effect causes the one-piece molded net or mesh yarn to expand or contract with temperature changes, thereby altering the mesh size. The thermochromic effect causes the color of the mesh yarn to change with temperature, adjusting light absorption and light transmittance. The shape memory effect is manifested as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape; as the temperature decreases, the material recovers from the temporary shape to the permanent shape. The thermochromic effect is characterized by the material color changing from light to dark as the temperature increases, and changing from dark to light as the temperature decreases.

[0007] Preferably, the thermoplastic shape memory polymer is thermoplastic polyurethane (TPU), and the thermochromic material is a reversible thermosensitive color-developing ink; the reversible thermosensitive color-developing ink is sprayed onto the surface of the thermoplastic polyurethane.

[0008] Reversible thermosensitive color-changing inks and thermoplastic polyurethane composites can also be composited using other methods, such as blending or encapsulating the reversible thermosensitive color-changing material in TPU microcapsules and then polymerizing it.

[0009] Preferably, the reversible thermosensitive color-developing ink changes color from light to dark as the temperature increases. The glass transition onset temperature (Tg) of thermoplastic polyurethane is 20℃-35℃, and the color change onset temperature of the reversible thermosensitive color-developing ink is 20℃-35℃. A reversible thermosensitive color-developing ink with a specific color change temperature can be selected as needed, such as the reversible thermosensitive color-developing ink from JEVEL (Qingdao) Industrial Co., Ltd.

[0010] Preferably, the integrally molded mesh is manufactured from thermoplastic polyurethane in one piece. The mesh type of the integrally molded mesh can be one of the following: a grid-like polygonal structure, a circular structure, or an elliptical structure. The surface of the integrally molded mesh is coated with a reversible thermosensitive color-developing ink. The glass transition onset temperature (Tg) of the thermoplastic polyurethane is 25°C, and the color change onset temperature of the reversible thermosensitive color-developing ink is 25°C. When the temperature is higher than 25°C, the thermoplastic polyurethane integrally molded mesh undergoes thermal expansion and deformation, the mesh size decreases, and the color changes from light to dark. The present invention sets 25°C as a temperature threshold based on the common ambient temperature range to ensure that the shade net responds effectively in most application scenarios.

[0011] Preferably, the thermoplastic shape memory yarn is woven in a warp and weft interlaced pattern. The glass transition onset temperature (Tg) of the thermoplastic polyurethane formed by the warp and weft interlacing of the thermoplastic shape memory yarn in the shade net is 25°C, and the color change onset temperature of the reversible thermosensitive color-developing ink is 25°C. When the temperature is higher than 25°C, the thermoplastic shape memory yarn undergoes thermal expansion and deformation, the mesh size becomes smaller, the thermoplastic shape memory yarn becomes thicker or wider, and the color changes from light to dark. The present invention sets 25°C as the temperature threshold based on the common ambient temperature range to ensure that the shade net responds effectively in most application scenarios.

[0012] This invention selects a reversible thermosensitive color-developing ink whose color-changing temperature is consistent with the glass transition initiation temperature of thermoplastic polyurethane. This allows the deformation of thermoplastic polyurethane and the color change of the reversible thermosensitive color-developing ink to produce a synergistic effect. This results in the shading mesh having larger pores and lighter colors at low temperatures, increasing light transmittance and illumination effect, and darker colors and smaller pores at high temperatures, reducing light transmittance and illumination effect, thus improving the shading effect.

[0013] Preferably, the shade net body is circumferentially connected with a hook assembly. The hook assembly includes a disc end fixed to the end of the thermoplastic shape memory wire or the side end of the integrally formed net. A lower hook ring is connected to the surface of the disc end, and an upper buckle is movably connected to the top of the lower hook ring. A lever plate is connected to the right side of the upper buckle. Elastic members are provided on the outer side of the movable ends of the lower hook ring and the upper buckle. A clamping member is provided on one side of the top of the lower hook ring. The hook assembly provides multiple fixing methods to adapt to different installation environments. The lower hook ring and the upper buckle form a closed loop through a movable connection, which facilitates hooking or attaching to external hooks. The elastic members ensure that the upper buckle automatically resets, maintaining a stable hooking state.

[0014] Preferably, the elastic component consists of end plate A, a support spring, and end plate B. The top of the upper buckle is connected and fixed to end plate A, and the left side of end plate A is connected and fixed to end plate B via the support spring. The bottom end of end plate B is fixed to the surface of the lower hook ring. The clamping component includes a threaded shaft that passes through a threaded hole at the top of the lower hook ring, and a clamping plate is movably installed at the bottom end of the threaded shaft. The elastic force of the support spring can push end plate A, and the force on end plate A can drive the upper buckle to rotate at the movable end of the lower hook ring, so that the upper buckle and the lower hook ring close, which is convenient for fixing with hooks or through-hooks on the side of the greenhouse. The clamping plate and the lower hook ring cooperate to form a clamping effect, providing an additional clamping method.

[0015] Preferably, the thermoplastic shape memory wire is wound and sleeved on the surface of the reinforcing rib assembly; the reinforcing rib assembly includes two torsion memory springs fixed at the center of the inner wall of the disc end, and the two torsion memory springs are fixed on the left and right sides of the flexible wire. The two torsion memory springs on both sides of the flexible wire are connected to the two disc ends, and when the thermoplastic shape memory wire expands and twists due to heat, it cooperates with the torsional force of the torsion memory springs, thereby controlling the horizontal position of the sunshade leaf; the flexible wire can be a nylon wire.

[0016] Preferably, the torsion memory spring is helical in shape and is light-absorbing black. When heated, the torsion memory spring attempts to recover its helical shape and generate torsion force, and it resets upon cooling. Several sunshade leaves are arranged in two equal rows on the outer side of the flexible wire, with the left and right rows of sunshade leaves arranged in a staggered, opposing configuration. The training process involves heating the alloy to a high-temperature phase, then twisting it to a desired specific angle, and cooling it while maintaining this twist. This process imprints the twisted shape within the material as its permanent memory. The staggered arrangement of the sunshade leaves, when the flexible wire rotates and drives the sunshade leaves to rotate, causes several sunshade leaves to be placed horizontally, filling the gaps in the warp and weft threads of the thermoplastic shape memory wire, further improving the sunshade effect.

[0017] Preferably, the leaf blade end of the shading leaf is vertically positioned, and the vertical end of the shading leaf is elliptical in shape.

[0018] This invention has at least the following beneficial effects: This invention utilizes the properties of a composite material of thermoplastic shape memory polymer and thermochromic material to enable the shade net to automatically adjust its light transmittance according to changes in ambient temperature. As the temperature rises from 25°C, the thermoplastic shape memory lines become thicker or wider, the mesh size decreases, and the color changes from light to dark. Conversely, as the temperature drops from its peak to 25°C, the thermoplastic shape memory lines become thinner or narrower, the mesh size increases, and the color changes from dark to light. This adaptive adjustment mechanism relies entirely on the material's inherent properties, requiring no external energy or manual operation, significantly improving the intelligence and energy efficiency of the shade net.

[0019] This invention optimizes shading performance under different temperature conditions through the synergistic effect of physical structural changes in mesh size adjustment and optical performance changes in mesh color depth adjustment. In strong light and high temperature environments, mesh shrinkage and color deepening together reduce heat and ultraviolet transmission; in weak light and low temperature environments, mesh expansion and color lightening together increase natural light transmission. This dual adjustment mechanism not only improves the adaptability of the shading net but also enhances its economic benefits in agricultural, construction, and other scenarios, such as promoting crop photosynthesis or reducing indoor energy consumption.

[0020] This invention enhances the mechanical strength and environmental adaptability of the shade net through the integrated design of hook assembly, reinforcing rib assembly, torsion memory spring, and sunshade leaf. The hook assembly provides multiple installation methods to ensure that the shade net is firmly fixed to different support structures. The torsion memory spring and sunshade leaf work together at high temperatures to further fill the mesh gaps and improve the shading effect. At the same time, it enhances the flexibility and wear resistance of the mesh surface, preventing damage from external impacts or contact with sharp objects in harsh weather conditions, thus extending its service life. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a shading net with automatically adjustable light transmittance woven from thermoplastic shape memory yarn under normal temperature conditions of 20-25 degrees Celsius. Figure 2 This is a schematic diagram of the thermoplastic shape memory yarn weaving of a shading net that can automatically adjust light transmittance, as proposed in this invention, under temperature expansion above 25 degrees Celsius. Figure 3 This is a schematic diagram of the spiral external structure of a shading net that can automatically adjust light transmittance according to the present invention. Figure 4 This is a schematic diagram of the thermoplastic shape memory spiral of a shading net that can automatically adjust light transmittance according to the present invention, showing its shrinkage state when cooled. Figure 5 This is a three-dimensional disassembly diagram of the thermoplastic shape memory wire, hook assembly, and reinforcing rib assembly in a shading net that can automatically adjust light transmittance according to the present invention. Figure 6 This is a three-dimensional disassembly diagram of the hook assembly in a shading net that can automatically adjust light transmittance, as proposed in this invention. Figure 7 For the present invention Figure 6 Enlarged structural diagram of A in the middle; Figure 8 This is a partial disassembly diagram of the reinforcing rib group in a shading net that can automatically adjust light transmittance, as proposed in this invention. Figure 9 This is a partial structural diagram of the integrally formed mesh of the shading net body in the present invention, which can automatically adjust the light transmittance.

[0023] In the picture: 1. Thermoplastic shape memory yarn; 10. Shade net body; 11. Mesh openings; 2. Hook assembly; 21. Disc end; 22. Lower hook ring; 23. Upper buckle ring; 24. Detachment plate; 25. End plate A; 26. Support spring; 27. End plate B; 28. Clamping component; 281. Threaded shaft; 282. Clamping plate; 3. Reinforcing ribs; 31. Flexible ribs; 32. Torque memory springs; 33. Shading leaves. Detailed Implementation

[0024] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. This application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] Reference Figures 1-9 A shading net capable of automatically adjusting light transmittance includes a shading net body 10 (the net body in the figure is a schematic diagram; the net body can extend outwards according to the actual usage area). The shading net body 10 is formed by weaving thermoplastic shape memory yarn 1 or by integral molding. The shading net body 10 is made of a temperature-sensitive composite material, which possesses both shape memory and thermochromic effects. The temperature-sensitive composite material includes a composite of a thermoplastic shape memory polymer and a thermochromic material. The shape memory effect is manifested as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape; as the temperature decreases, the material returns from the temporary shape to the permanent shape. The thermochromic effect is manifested as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape; as the temperature decreases, the material returns from the temporary shape to the permanent shape. As temperature increases, the material color changes from light to dark; as temperature decreases, the material color changes from dark to light. The glass transition onset temperature (Tg) of the thermoplastic polyurethane matrix is ​​set at 25 degrees Celsius. By adjusting the ratio of soft and hard segments and the modification process, setting the glass transition temperature Tg to 20-35 degrees Celsius is a mature technology, such as the TPU produced by Wanhua Chemical Group Co., Ltd. and BASF Europe. The thermochromic material is a reversible thermosensitive color-developing ink. The reversible thermosensitive color-developing ink is sprayed onto the surface of the thermoplastic polyurethane. The color of the reversible thermosensitive color-developing ink changes from light to dark as the temperature increases. The specific reversible thermosensitive color-developing ink is selected according to the required color-changing temperature. The reversible thermosensitive color-developing ink is an existing mature material. Example 1

[0026] like Figure 1-2As shown in Figures 6-7, a shading net capable of automatically adjusting light transmittance includes a shading net body 10. The shading net body 10 is woven from thermoplastic shape memory yarn 1, which is a rectangular strip. Hooks 2 are provided at both ends of the thermoplastic shape memory yarn 1. The thermoplastic shape memory yarn 1 is partially made of a temperature-sensitive composite material, which possesses both shape memory and thermochromic effects. The temperature-sensitive composite material includes a composite of thermoplastic polyurethane and thermochromic materials. The shape memory effect manifests as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape; as the temperature decreases, the material changes from a fixed shape to a fixed shape. The temporary shape is restored to the permanent shape; the thermochromic effect is manifested as follows: as the temperature rises, the material color changes from light to dark, and as the temperature decreases, the material color changes from dark to light; the thermoplastic shape memory line 1 is woven into a warp and weft interlaced pattern, the thermochromic material is a reversible thermosensitive color-developing ink, the shading net formed by the warp and weft interlacing of the thermoplastic shape memory line 1 has a glass transition initiation temperature (Tg) of 25℃, the color change initiation temperature of the reversible thermosensitive color-developing ink is 25℃, when the temperature is higher than 25℃, the thermoplastic shape memory line 1 deforms, the mesh becomes smaller, the long strip thermoplastic shape memory line 1 becomes wider, and the color becomes darker. This invention selects a reversible thermosensitive color-developing ink with a color-changing temperature consistent with the glass transition temperature of thermoplastic polyurethane. This results in a synergistic effect between the deformation of thermoplastic polyurethane and the color change of the reversible thermosensitive color-developing ink. At low temperatures, the shading mesh aperture increases and the color becomes lighter, increasing light transmittance and illumination effect. At high temperatures, the color becomes darker and the aperture decreases, reducing light transmittance and illumination effect, thus improving the shading effect.

[0027] The hook assembly 2 includes a disc end 21 fixed to the end of the thermoplastic shape memory wire 1. A lower hook ring 22 is connected to the surface of the disc end 21, and an upper buckle 23 is movably connected to the top of the lower hook ring 22. A lever plate 24 is connected to the right side of the upper buckle 23. Elastic members are provided on the outer side of the movable ends of the lower hook ring 22 and the upper buckle 23. A clamping member 28 is provided on one side of the top of the lower hook ring 22. The elastic member consists of an end plate A25, a support spring 26, and an end plate B27. The top of the upper buckle 23 is connected and fixed to the end plate A25. The left side of the end plate A25 is connected and fixed to the end plate B27 through the support spring 26, and the bottom end of the end plate B27 is fixed to the surface of the lower hook ring 22. The clamping member 28 includes a threaded shaft 281 that passes through a threaded hole and is inserted into the top of the lower hook ring 22. A clamping plate 282 is movably installed at the bottom end of the threaded shaft 281. The hook assembly 2 is used to fix the shade net to the external support structure. The threaded shaft 281 rotates and moves downward in the threaded hole of the lower hook ring 22, pushing the clamping plate 282 with its shaft end. The clamping plate 282 and the lower hook ring 22 cooperate to form a clamping effect, providing additional clamping methods. The hook assembly 2 provides multiple fixing methods to adapt to different installation environments. The lower hook ring 22 and the upper buckle ring 23 form a closed loop through a movable connection, which is convenient for hooking or attaching to external hooks. The elastic element ensures that the upper buckle ring 23 automatically resets and maintains a stable hooking state. The clamping element 28 allows the shade net to be directly clamped on a flat surface such as a board frame, enhancing installation flexibility. The elastic force of the support spring 26 can push the end plate A25. The force on the end plate A25 can drive the upper buckle ring 23 to rotate at the movable end of the lower hook ring 22, so that the upper buckle ring 23 and the lower hook ring 22 are closed, which is convenient for fixing to hooks or through hooks on the side of the greenhouse. Example 2

[0028] like Figure 3-8 As shown, a shade net that can automatically adjust the light transmittance includes a shade net body 10, which is woven from thermoplastic shape memory yarn 1. Hook groups 2 are provided on both ends of the thermoplastic shape memory yarn 1, and the thermoplastic shape memory yarn 1 is wound and sleeved on the surface of the reinforcing rib group 3. Part 1 of the thermoplastic shape memory line is made of a thermosensitive composite material. The thermosensitive composite material has both shape memory effect and thermochromic effect. The thermosensitive composite material is a composite material including thermoplastic polyurethane and thermochromic material. The shape memory effect manifests as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape, and as the temperature falls, the material returns from the temporary shape to the permanent shape. Thermochromic effect is characterized by the material color changing from light to dark as the temperature rises and from dark to light as the temperature falls.

[0029] The shading net formed by the interlacing of thermoplastic shape memory lines 1 has a glass transition temperature (Tg) of 25°C. The reversible thermosensitive color-changing ink also has a color-changing initiation temperature of 25°C. When the temperature exceeds 25°C, the thermoplastic shape memory lines 1 undergo thermal expansion and deformation, resulting in smaller mesh openings, wider diameters, and darker colors. This invention selects a reversible thermosensitive color-changing ink with a color-changing temperature consistent with the glass transition temperature of thermoplastic polyurethane. This creates a synergistic effect between the deformation of the thermoplastic polyurethane and the color change of the reversible thermosensitive color-changing ink. At low temperatures, the shading net openings become larger and the color becomes lighter, increasing light transmittance and illumination. At high temperatures, the color becomes darker and the openings become smaller, reducing light transmittance and illumination, thus improving the shading effect.

[0030] The hook assembly 2 includes a disc end 21 fixed to the end of the thermoplastic shape memory wire 1. A lower hook ring 22 is connected to the surface of the disc end 21, and an upper buckle 23 is movably connected to the top of the lower hook ring 22. A lever plate 24 is connected to the right side of the upper buckle 23. Elastic members are provided on the outer side of the movable ends of the lower hook ring 22 and the upper buckle 23. A clamping member 28 is provided on one side of the top of the lower hook ring 22. The elastic member consists of an end plate A25, a support spring 26, and an end plate B27. The top of the upper buckle 23 is connected and fixed to the end plate A25. The left side of the end plate A25 is connected and fixed to the end plate B27 through the support spring 26, and the bottom end of the end plate B27 is fixed to the surface of the lower hook ring 22. The clamping member 28 includes a threaded shaft 281 that passes through a threaded hole and is inserted into the top of the lower hook ring 22. A clamping plate 282 is movably installed at the bottom end of the threaded shaft 281.

[0031] like Figure 8 As shown, the reinforcing rib group 3 includes two torsion memory springs 32 fixed at the center of the inner wall of the disc end 21, and the two torsion memory springs 32 are fixed on the left and right sides of the flexible line 31.

[0032] The torsion memory spring 32 is helical and is light-absorbing black. When heated, the torsion memory spring 32 can attempt to restore its helical shape to generate torsional force. The torsion memory spring 32 resets when cooled.

[0033] The flexible line 31 has several sunshade leaves 33 arranged in two rows at equal intervals on the outer side, and the two rows of sunshade leaves 33 are arranged in opposite directions and staggered.

[0034] The blade end of the sunshade leaf 33 is set vertically, and the vertical blade end of the sunshade leaf 33 is designed in an elliptical shape.

[0035] Thermoplastic shape memory yarn 1, as the core component of the shade net, forms an adjustable grid base through its interwoven warp and weft structure. Hook and hook assembly 2 is used to fix the shade net to an external support structure such as a greenhouse frame, while reinforcing rib assembly 3 serves as a support frame to ensure the flatness and stable unfolding of the net surface, making the shade net easy to install and disassemble while maintaining the overall structural coordination. Thermosensitive composite material is the key to achieving automatic adjustment. The shape memory effect causes the yarn to expand or contract when the temperature changes, thereby changing the mesh size. The thermochromic effect causes the color of the yarn to change with the temperature, adjusting light absorption and transmittance. The two effects work together to enable the shade net to dynamically respond to the ambient temperature and achieve precise control of light transmittance. The thermochromic material can be sprayed onto the surface of the shade net body later to achieve color change. The threaded shaft 281 rotates and moves downward in the threaded hole of the lower hook ring 22, pushing the clamping plate 282 with its shaft end. The clamping plate 282 and the lower hook ring 22 cooperate to form a clamping action, providing an additional clamping method. Two torsion memory springs 32 on both sides of the flexible wire 31 are connected to the two disc ends 21. When the thermoplastic shape memory wire 1 expands and twists due to heat, it cooperates with the torsional force of the torsion memory springs 32, thereby controlling the horizontal position of the sunshade leaf 33. This allows the sunshade leaf 33 to further fill the gaps in the warp and weft mesh of the thermoplastic shape memory wire 1, improving the sunshade effect. The flexible wire 31 can be made of high-performance engineering plastics, such as nylon. These materials have excellent mechanical strength, fatigue resistance, and good heat resistance, typically withstanding 80-120℃ for extended periods, sufficient to work stably and effectively transmit heat at 60℃. Torque transfer; the training process involves heating the alloy spring material to a high-temperature phase, then twisting it to a specific angle as desired, and cooling it while maintaining this twisted state. This process imprints the twisted shape inside the material as its permanent memory. When sunlight irradiates it and raises its temperature above the phase transition temperature, it is forced to return to the twisted state it was trained to remember. The torsion memory spring 32 thus controls the flexible wire 31 to deflect to a certain extent. The sunshade leaves 33 are staggered. When the flexible wire 31 rotates, it drives the sunshade leaves 33 to rotate. Several sunshade leaves 33 are placed horizontally, filling the gaps in the warp and weft threads of the thermoplastic shape memory wire 1, further improving the sunshade effect. After the sunshade leaves 33 rotate, they form a whole with the sunshade net formed by the thermoplastic shape memory wire 1, which improves the protective effect of the sunshade net to a certain extent. The hook assembly 2 provides multiple fixing methods to adapt to different installation environments; the lower hook ring 22 and the upper buckle ring 23 form a closed loop through a movable connection, which is convenient for hooking or attaching to external hooks; the elastic element ensures that the upper buckle ring 23 automatically resets and maintains a stable hooking state; the clamping element 28 allows the shade net to be directly clamped on a flat surface such as a board frame, enhancing installation flexibility; the elastic force of the support spring 26 can push the end plate A25, and the force on the end plate A25 can drive the upper buckle ring 23 to rotate at the movable end of the lower hook ring 22, so that the upper buckle ring 23 and the lower hook ring 22 are closed, which is convenient for fixing to hooks or through hooks on the side of the greenhouse. Example 3

[0036] like Figure 9 As shown, a shade net that can automatically adjust the light transmittance includes a shade net body 10, which is a one-piece molded net, and a hook assembly 2 is connected to the side end of the one-piece molded net. The integrally molded mesh is manufactured by integral molding of thermoplastic shape memory polymer, and the mesh type 11 of the integrally molded mesh can be one of the following: grid-like polygonal, circular, or elliptical structure design. The surface of the integrally molded mesh is covered with a thermochromic material. The shape memory effect manifests as follows: as the temperature rises, the material changes from a preset permanent shape to a temporary shape, and as the temperature falls, the material returns from the temporary shape to the permanent shape. Thermochromic effect is characterized by the material color changing from light to dark as the temperature rises and from dark to light as the temperature falls.

[0037] The thermochromic material is a reversible thermosensitive color-developing ink. When the temperature of the integrally molded mesh is below 25℃, the mesh body shrinks, the mesh holes become larger, and the color becomes lighter; when the temperature is above 25℃, the mesh body expands, the mesh holes become smaller, and the color becomes darker.

[0038] The hook assembly 2 includes a disc end 21 fixed to the end of the thermoplastic shape memory line 1. A lower hook ring 22 is connected to the surface of the disc end 21, and an upper buckle 23 is movably connected to the top of the lower hook ring 22. A lever plate 24 is connected to the right side of the upper buckle 23. Elastic members are provided on the outer side of the movable ends of the lower hook ring 22 and the upper buckle 23. A clamping member 28 is provided on one side of the top of the lower hook ring 22.

[0039] The elastic component consists of end plate A25, support spring 26 and end plate B27. The top of the upper buckle 23 is connected and fixed to end plate A25. The left side of end plate A25 is connected and fixed to end plate B27 through support spring 26, and the bottom of end plate B27 is fixed to the surface of lower hook ring 22.

[0040] The clamping member 28 includes a threaded shaft 281 that passes through the top of the hook ring 22 via a threaded hole, and a clamping plate 282 is movably mounted at the bottom end of the threaded shaft 281.

[0041] When the shade net body 10 adopts a one-piece molded mesh structure, that is, the entire mesh structure is manufactured by one-time molding of thermoplastic shape memory polymer, and the mesh is designed as a grid-like polygonal structure, the one-piece molding avoids the seams and nodes at the intersection of warp and weft threads in traditional woven nets. The overall structure is more uniform and firm, and less prone to local breakage or deformation. The polygonal grid structure, such as hexagons, rhombuses, circles, ellipses, etc., has good mechanical stability, can effectively disperse external forces, enhance the tensile strength and wind load resistance of the net body, and has no loose threads or joints, reducing wear and loosening problems caused by long-term use or harsh weather, and extending service life. The mesh is made of thermoplastic polyurethane, and its deformation behavior under temperature changes, such as the opening and closing of the holes, is more synchronous and consistent, without the problem of local response lag or incoordination. The polygonal mesh can shrink as a whole when the temperature rises and return to its original shape and the holes enlarge when the temperature drops. The deformation process is more controllable and predictable, and the light transmittance adjustment is more precise. The one-piece molding structure avoids gaps between the lines. At high temperatures, the mesh shrinks more tightly, resulting in better shading effect. At low temperatures, the mesh opens more fully, allowing more light to pass through. The shading net body structure under this design does not require multiple processes such as warp and weft weaving and sewing, resulting in high production efficiency and suitability for large-scale standardized production. This invention sets 25°C as the temperature threshold, which is based on the common ambient temperature range to ensure that the shade net responds effectively in most application scenarios. When the temperature is below 25°C, the net wires shrink and the color lightens to maximize light transmission and promote light and temperature rise; when the temperature is above 25°C, the net wires expand and the color darkens to minimize light transmission and reduce heat load. This threshold design improves the reliability and practicality of the system.

[0042] Without human intervention or the use of external energy, the sunshade net automatically adjusts its light transmittance based on sunlight and ambient temperature, achieving intelligent management by allowing more sunlight to pass through when needed and reducing sunlight transmission when shading and cooling are required. It combines the changes in mesh size due to physical structural variations with the color of the warp and weft threads changing with temperature in terms of optical performance. This achieves the dual benefits of shading and light transmission, resulting in significant effectiveness and economic benefits.

[0043] Because the sunshade net involved in this patent has the dual functions of shading and light transmission, it can effectively prevent plants, people, equipment and other items from being sunburned or damaged in strong sunlight and high temperature weather; in insufficient sunlight and low temperature weather, it can transmit light to plants, people, equipment and other items, and play a role in warming them.

[0044] The temperature-sensitive composite material of the shading net responds to changes in ambient temperature, automatically adjusting its light transmittance without external energy or human intervention. The thermoplastic shape memory polymer (SMP) 1 uses shape memory polyurethane as its raw material. It can obtain its initial shape through conventional polymer preparation methods. Under external temperature stimuli, it can correspondingly change its shape. After the stimulus is removed, its deformed state is fixed. If the external environment changes again in a specific way and according to a certain pattern, it can reversibly return to its initial state. This material has a defined glass transition temperature range, and its molecular network consists of a stationary phase and a reversible phase. When the temperature changes, the polymer chain segment movement is activated, and the material transitions between a glassy state and a highly elastic state, thus allowing the material to change between a temporary shape and a preset permanent shape. The "memory" characteristic of thermoplastic shape memory polymers is mainly due to its two different internal structures: a stationary phase and a reversible phase. The stationary phase mainly maintains the original shape of the material, while the reversible phase is used to fix the temporary shape of the material, freezing or softening near the material transition temperature. When certain conditions are changed, the reversible phase will return to its initial form, thus exercising the "memory" function of SMP.

[0045] Working principle: Taking the warp and weft woven thermoplastic shape memory yarn (1) woven mesh as an example, according to Figure 6 and Figure 7 As shown, when the shading net is laid out, the lower hook ring 22 and the upper buckle ring 23 cooperate to hook the position with hooks or hanging rings, or the hanging rope containing counterweight is passed through the loop formed by the lower hook ring 22 and the upper buckle ring 23 for hoisting, or the rope is knotted and fixed when it passes through, so that the shading net formed by the thermoplastic shape memory line 1 is unfolded to form a shading effect. When there are protruding panels on both sides of the greenhouse, the clamping plate 282 cooperates with the lower hook ring 22 to form a clamp on the surface of the protruding panel. During the clamping process, the threaded shaft 281 rotates and moves down in the threaded hole of the lower hook ring 22, driving the threaded shaft 281 to push the clamping plate 282. The clamping plate 282 and the lower hook ring 22 cooperate to fix the surface of the protruding panel on both sides of the greenhouse.

[0046] At room temperature (20-25℃): such as Figure 1 As shown, the temperature-sensitive material is in the initial state, and the color of the warp and weft threads of the thermoplastic shape memory line 1 is in a colorless state. Under these conditions, most sunlight can pass through the mesh holes and the warp and weft threads, and the plants, equipment and other items under the sunshade net can receive sufficient light. High temperature conditions >25℃: such as Figure 2As shown, the temperature-sensitive material is in a temporary shape. As the light intensifies and the ambient temperature rises, the warp and weft threads gradually expand and widen, the mesh size of the sunshade net decreases, and the color of the warp and weft threads darkens. Under these conditions, less and less sunlight can pass through the mesh and warp and weft threads. At this time, plants, equipment, and other items under the sunshade net gradually receive less sunlight exposure, achieving a certain temperature drop in high-temperature environments, thus avoiding high-temperature sunburn and damage, and achieving a good shading effect.

[0047] Taking a spiral thermoplastic shape memory wire (1) woven mesh as an example, at a high temperature of >25℃, the temperature-sensitive material is in a temporary shape state; as the light intensity increases and the ambient temperature rises, the warp and weft wires gradually expand, the wire diameter becomes thicker, the mesh size of the sunshade net becomes smaller, and at the same time, the color of the warp and weft wires darkens; simultaneously, according to Figure 8 As shown, when the thermoplastic shape memory wire 1 expands due to heat, it rotates to a certain extent during expansion due to its spiral state. The torsion memory spring 32 absorbs heat simultaneously. When the surface temperature of the torsion memory spring 32 reaches 60°C, the torsion memory spring 32 deforms due to its spiral shape and material. The thermoplastic shape memory wire 1 and the torsion memory spring 32 work together to drive the flexible wire 31 to form a certain torsional force, causing the sunshade leaf 33 to overlap during rotation, resulting in a better sunshade effect. At the same time, the flexible wire 31 and the sunshade leaf 33 work together to improve the flexibility and pressure resistance of the sunshade net formed by the thermoplastic shape memory wire 1, preventing the sunshade net from being worn or cut by sharp objects in bad weather, thus affecting the sunshade effect of the net surface.

[0048] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A sunshade net capable of automatically adjusting light transmittance, characterized in that, The sunshade net body (10) is formed by weaving or one-piece forming net, and is made of a temperature-sensitive composite material with shape memory effect and thermochromic effect. The shape memory effect is that the material changes from a preset permanent shape to a temporary shape as the temperature rises, and the material returns to the permanent shape from the temporary shape as the temperature drops. The thermochromic effect is that the color of the material changes from light to dark as the temperature rises, and the color of the material changes from dark to light as the temperature drops.

2. The sunshade net capable of automatically adjusting light transmittance according to claim 1, characterized in that, The thermoplastic shape memory polymer is thermoplastic polyurethane (TPU), and the thermochromic material is reversible heat-sensitive color ink.

3. The sunshade net capable of automatically adjusting light transmittance according to claim 2, characterized in that, The reversible heat-sensitive color ink changes color from light to dark as the temperature rises, and the thermoplastic polyurethane glass transition temperature (Tg) is 20-35℃, and the reversible heat-sensitive color ink color change temperature is 20-35℃.

4. The sunshade net capable of automatically adjusting light transmittance according to claim 3, characterized in that, The one-piece net is made of thermoplastic polyurethane, and the mesh (11) type of the one-piece net can be one of grid-shaped polygon, circular, and elliptical structure design.

5. The sunshade net capable of automatically adjusting light transmittance according to claim 3, characterized in that, The reversible heat-sensitive color ink is sprayed on the surface of the thermoplastic polyurethane, and the thermoplastic polyurethane glass transition temperature (Tg) is 25℃, and the reversible heat-sensitive color ink color change temperature is 25℃.

6. The sunshade net capable of automatically adjusting the light transmittance according to claim 4 or 5, characterized in that, When the temperature is higher than 25℃, the thermoplastic polyurethane one-piece net deforms, the mesh (11) becomes smaller, and the color becomes darker. The thermoplastic shape memory wire (1) is woven by interlacing warp and weft, and the thermoplastic shape memory wire (1) is woven into a sunshade net with a thermoplastic polyurethane glass transition temperature (Tg) of 25℃ and a reversible heat-sensitive color ink color change temperature of 25℃. When the temperature is higher than 25℃, the thermoplastic shape memory wire (1) expands and deforms, the mesh (11) becomes smaller, the thermoplastic shape memory wire becomes thicker or wider, and the color becomes darker. The sunshade net body is circumferentially connected with a hooking group (2), the hooking group (2) includes a disc end (21) fixed to the end of the thermoplastic shape memory wire (1) or the side end of the one-piece net, the disc end (21) is connected with a lower hook ring (22) on the surface, and the top end of the lower hook ring (22) is movably connected with an upper buckle ring (23), the right side of the upper buckle ring (23) is connected with a push plate (24), the outer side of the movable end of the lower hook ring (22) and the upper buckle ring (23) is provided with an elastic member, and the top end of the lower hook ring (22) is provided with a clamping member (28) on one side.

7. The sunshade net capable of automatically adjusting light transmittance according to claim 6, characterized in that, The elastic member is composed of an end plate A (25), a supporting spring (26) and an end plate B (27), the upper clamping ring (23) top is connected with the end plate A (25), the left side of the end plate A (25) is connected with the end plate B (27) through the supporting spring (26), and the bottom of the end plate B (27) is fixed on the surface of the lower clamping ring (22); the clamping piece (28) comprises a threaded rotating shaft (281) which is inserted into the top of the lower clamping ring (22) through a threaded hole, and the bottom of the threaded rotating shaft (281) movably installs a clamping plate (282).

8. The sunshade net capable of automatically adjusting light transmittance according to claim 7, characterized in that, The thermoplastic shape memory wire (1) is wound on the surface of the reinforcing rib group (3); the reinforcing rib group (3) comprises two torsion memory springs (32) fixed on the inner wall center of the disc end (21), and the two torsion memory springs (32) are fixed on the left and right sides of the flexible wire (31).

9. The sunshade net capable of automatically adjusting light transmittance according to claim 8, characterized in that, The torsion memory spring (32) is in a spiral shape, and the color of the torsion memory spring (32) is light-absorbing black; the torsion memory spring (32) can try to restore the torsional force after being heated, and the torsion memory spring (32) resets when cooled; the outside of the flexible wire (31) is provided with a plurality of sunshade leaves (33) in double rows at equal intervals, and the sunshade leaves (33) in the left and right rows are oppositely and staggeredly arranged.

10. The sunshade net capable of automatically adjusting light transmittance according to claim 9, characterized in that, The blade end of the sunshade leaf (33) is vertically arranged, and the vertical plate end of the sunshade leaf (33) is designed in an oval shape.

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