Extrusion equipment and method for producing high-insulation pvb interlayer

Abstract

This invention relates to the field of extrusion molding technology, specifically disclosing an extrusion equipment and method for producing high-insulation PVB interlayer films. The extrusion equipment includes: a frame; a screw extrusion unit; an eccentric suspension throwing unit; a variable cross-section flow channel unit; and a feeding unit. This invention uses a rotating drum to drive an eccentrically oscillating suspension sleeve, forcibly throwing up nanoparticles that have settled to the bottom of the extrusion cylinder, eliminating agglomerate pulses and preventing the formation of crystal points in the PVB film; simultaneously, it removes the deposited layer in the screw grooves, eliminates extrusion cylinder wear, and ensures long-term stable extrusion pressure; in the extrusion flow channel formed by the extrusion head and the guide core, the radial expansion member periodically adjusts the pressure, rolling up the particles and promoting dispersion, so that the melt passes through the subsequent filtration device without high-intensity agglomerate impact, effectively preventing fatigue fracture of the filter element.

Description

Technical Field

[0001] This invention relates to the field of extrusion molding technology, and more specifically, to an extrusion apparatus and method for producing high-insulation PVB interlayer film. Background Technology

[0002] In the production of high-insulation PVB interlayer films, in order to achieve excellent insulation performance, it is often necessary to add a high concentration of nano-inorganic insulating particles (such as nano-antimony tin oxide ATO, nano-indium tin oxide ITO, or cesium tungsten bronze) to the matrix. These particles have the characteristics of high hardness and high specific surface area, and their uniform dispersion is the key to ensuring the optical quality and thermal insulation performance of the thin film.

[0003] When melt containing high-hardness nanoparticles enters the extrusion equipment, a low-pressure reflux zone exists on the back of the screw edge, where the melt flows slowly. Due to their high inertia, nanoparticles tend to deposit and accumulate in this area. When they accumulate to a certain extent, they are suddenly swept away by the main flow channel, forming a pulse of instantaneous high-concentration agglomerates. This eventually forms visible "crystal points" or "fish-eye" defects in the PVB film. At the same time, in the microstructure at the bottom of the screw groove, a retention layer is formed due to the deposition of nanoparticles. The particles continue to agglomerate in the dead corners of the micro-vortex, such as the back of the edge. Once hard agglomerates are formed, they will scratch the inner wall of the extrusion barrel under subsequent extrusion pressure, causing uneven radial wear and seriously affecting the long-term stability of the extrusion pressure. Summary of the Invention

[0004] To overcome the above-mentioned technical problems, this invention proposes an extrusion equipment and method for producing high-insulation PVB interlayer film.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] An extrusion apparatus for producing a high-insulation PVB interlayer film includes:

[0007] frame;

[0008] A spiral extrusion unit, mounted on a frame, includes an extrusion cylinder fixed to the frame and an extrusion screw rotatably mounted inside the extrusion cylinder;

[0009] An eccentric suspension throwing unit is located in the middle section of the extrusion cylinder and includes a rotating cylinder rotatably connected to the extrusion cylinder and a suspension sleeve eccentrically and movably embedded in the rotating cylinder.

[0010] A variable cross-section flow channel unit is disposed at the outlet end of an extrusion barrel, including an extrusion head that is detachably connected to the extrusion barrel and a flow guide core that is coaxially fixed inside the extrusion head. An extrusion flow channel is formed between the extrusion head and the flow guide core, and a radial expansion member is disposed inside the extrusion flow channel.

[0011] The feeding unit is located at the inlet end of the extrusion cylinder and is used to feed the extruded raw materials into the extrusion cylinder.

[0012] As a further aspect of the present invention: the spiral extrusion unit further includes a drive motor fixedly installed at one end of the extrusion cylinder, the output end of the drive motor being connected to the extrusion screw, and the extrusion screw being provided with spiral extrusion blades adapted to the interior of the extrusion cylinder.

[0013] As a further aspect of the present invention: the eccentric suspension throwing unit further includes a sealing ring fixed to the inner wall of both ends of the extrusion cylinder. The sealing ring is used to axially limit both ends of the suspension sleeve. A lubrication cavity is formed between the suspension sleeve and the rotating cylinder. The two ends of the lubrication cavity are respectively connected to an inlet pipe and a outlet pipe.

[0014] As a further aspect of the present invention: a rotary motor is fixedly installed on the frame, a rotary gear is connected to the output end of the rotary motor, a rotary gear ring that meshes with the rotary gear is provided on the outside of the rotating drum, and a protruding rib that abuts against the suspension sleeve is provided inside the rotating drum.

[0015] As a further embodiment of the present invention: the drainage core is coaxially fixed inside the extrusion head by a plurality of circumferentially distributed fixing columns, the drainage core is provided with an arc-shaped recess, and the radial expansion member is located at the arc-shaped recess.

[0016] As a further aspect of the present invention: the radial expansion member includes a radial expansion bladder disposed on the inner wall of the extrusion head and adapted to the arc-shaped recess, and the drainage core is provided with an air nozzle communicating with the interior of the radial expansion bladder.

[0017] As a further aspect of the present invention: the drainage core is provided with a number of U-shaped channels in the circumferential direction, and each of the two ends of the U-shaped channels is provided with a connecting hole, and each of the corresponding fixing posts at both ends of the U-shaped channels is provided with a connecting nozzle that communicates with the connecting hole on the same side.

[0018] As a further aspect of the present invention: the feeding unit includes a hopper connected to the inlet end of the extrusion cylinder, and rotating shafts are symmetrically and rotatably installed on both sides of the hopper. A deflector plate is provided on the rotating shaft, and driven gears meshing with each other are provided on both sets of rotating shafts; a drive gear is sleeved on the extrusion screw, and an intermediate gear meshing with the drive gear is rotatably installed on the outer wall of the hopper. The intermediate gear meshes with one set of driven gears.

[0019] As a further aspect of the present invention: a central chamber is provided inside the rotating shaft, and a permeable membrane communicating with the inside of the hopper is embedded in the central chamber; a bearing seat is fixedly installed outside the hopper, and one end of the rotating shaft is rotatably sleeved in the bearing seat; an annular transition chamber is provided inside the bearing seat, and an infusion tube communicating with the annular transition chamber is provided outside the bearing seat; a connecting cavity communicating with the central chamber is provided at one end of the rotating shaft, and a plurality of through holes communicating with the annular transition chamber are provided circumferentially on the inner wall of the connecting cavity.

[0020] This invention also discloses a method for producing high-insulation PVB interlayer film using extrusion equipment, comprising the following steps:

[0021] Step 1: The mixture of PVB resin and nano-insulating particles is fed into the extrusion cylinder through the feeding unit, heated and melted, and then continuously pushed towards the extrusion head by the extrusion screw;

[0022] Step 2: Drive the suspension sleeve to oscillate circumferentially by rotating the drum, periodically throwing the nanoparticles deposited at the bottom upwards and extruding the melt in all directions.

[0023] Step 3: When the raw material flows through the extrusion channel, the radial expansion member periodically contracts and expands, dynamically changing the cross-sectional area of ​​the channel. The increased flow velocity in the contraction section rolls up the deposited particles, while the turbulence generated in the expansion section promotes further mixing.

[0024] Step 4: The fully dispersed raw material is extruded from the extruder outlet.

[0025] The beneficial effects of this invention are:

[0026] This invention drives the suspension sleeve to periodically eccentrically oscillate inside the extrusion cylinder by rotating the cylinder, which forces the nano-inorganic heat insulation particles that have settled to the bottom to be continuously thrown upwards, directly destroying the particle deposition environment, thereby eliminating the formation of instantaneous high-concentration agglomerate pulses and avoiding defects such as crystal points and fish eyes in the subsequent high heat insulation PVB film.

[0027] The continuous oscillation of the suspension sleeve effectively removes the stagnant layer formed by the deposition of nanoparticles at the bottom of the screw groove, eliminating the long-term adhesion and compaction of microparticles in the dead corner of the micro-zone eddy. This not only avoids uneven radial wear caused by the peeling off of the deposit layer and scratching the inner wall of the extrusion cylinder, but also ensures the high stability of the extrusion pressure during long-term continuous operation of the equipment.

[0028] In the extrusion channel formed by the extruder head and the guide core, the periodic contraction and expansion motion of the radial expander creates a dynamic variable pressure control environment. The high flow rate during the contraction phase rolls up the deposited particles, and the micro-turbulence during the expansion phase promotes uniform dispersion. When the melt after upstream dispersion passes through the subsequent filtration device, the absence of high-intensity agglomerate pulses effectively avoids local fatigue fracture of the subsequent filtration elements. Attached Figure Description

[0029] The invention will now be further described with reference to the accompanying drawings.

[0030] Figure 1 This is a three-dimensional schematic diagram of an extrusion device for producing a high-insulation PVB interlayer film according to the present invention;

[0031] Figure 2 This is a three-dimensional schematic diagram from another perspective of an extrusion device for producing a high-insulation PVB interlayer film according to the present invention;

[0032] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0033] Figure 4 This is a cross-sectional view of an extrusion apparatus for producing a high-insulation PVB interlayer film according to the present invention;

[0034] Figure 5 This is an axial cross-sectional view of an eccentric suspension throwing unit in an extrusion device for producing a high-insulation PVB interlayer film according to the present invention.

[0035] Figure 6 This is a radial cross-sectional view of an eccentric suspension throwing unit in an extrusion device for producing a high-insulation PVB interlayer film according to the present invention.

[0036] Figure 7 This is a cross-sectional view of an eccentric suspension throwing unit in an extrusion device for producing a high-insulation PVB interlayer film according to the present invention.

[0037] Figure 8 This is an axial sectional view of a variable cross-section flow channel unit in an extrusion device for producing a high-insulation PVB interlayer film according to the present invention.

[0038] Figure 9 This is a schematic diagram of the structure of the rotating shaft and the dial plate in an extrusion device for producing high heat-insulating PVB interlayer film according to the present invention;

[0039] Figure 10 This is a cross-sectional view of the rotating shaft and bearing housing in an extrusion device for producing a high-insulation PVB interlayer film according to the present invention.

[0040] Figure 11 for Figure 10 Enlarged view of section B in the middle.

[0041] In the picture:

[0042] 100. Rack;

[0043] 200, Screw extrusion unit; 210, Extrusion cylinder; 220, Drive motor; 230, Extrusion screw; 240, Screw extrusion blades;

[0044] 300. Eccentric suspension throwing unit; 310. Sealing ring; 320. Rotary drum; 330. Lubrication chamber; 331. Liquid inlet pipe; 332. Liquid outlet pipe; 340. Suspension sleeve; 350. Rotary motor; 360. Rotary gear; 370. Rotary gear ring; 380. Raised rib;

[0045] 400, Variable cross-section flow channel unit; 410, Extruder head; 420, Guide core; 421, Extrusion flow channel; 430, Fixing column; 440, Arc-shaped recess; 450, Radial expansion bladder; 460, Air nozzle; 470, U-shaped flow channel; 480, Connecting hole; 490, Connecting nozzle;

[0046] 500. Feeding unit; 510. Hopper; 520. Rotating shaft; 521. Central chamber; 522. Permeable membrane; 523. Connecting chamber; 524. Through hole; 530. Paddle plate; 540. Driven gear; 550. Drive gear; 560. Intermediate gear; 570. Bearing seat; 571. Annular transition chamber; 580. Infusion tube. Detailed Implementation

[0047] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0048] Please see Figure 1 and Figure 2 This invention discloses an extrusion device for producing high heat insulation PVB interlayer film, including a frame 100, a spiral extrusion unit 200, an eccentric suspension throwing unit 300, a variable cross-section flow channel unit 400, and a feeding unit 500.

[0049] Please see Figure 4 The spiral extrusion unit 200 is disposed on the frame 100 and includes an extrusion cylinder 210 fixed on the frame 100 and an extrusion screw 230 rotatably disposed in the extrusion cylinder 210.

[0050] Please see Figure 5 The eccentric suspension throwing unit 300 is disposed in the middle section of the extrusion cylinder 210, and includes a rotating cylinder 320 rotatably connected to the extrusion cylinder 210 and a suspension sleeve 340 eccentrically and movably embedded in the rotating cylinder 320.

[0051] Please see Figure 8The variable cross-section flow channel unit 400 is disposed at the outlet end of the extrusion barrel 210, including an extrusion head 410 detachably connected to the extrusion barrel 210 and a flow guide core 420 coaxially fixed inside the extrusion head 410. An extrusion flow channel 421 is formed between the extrusion head 410 and the flow guide core 420, and a radial expansion member is disposed inside the extrusion flow channel 421.

[0052] The feeding unit 500 is disposed at the inlet end of the extrusion cylinder 210 and is used to feed extruded raw materials into the extrusion cylinder 210;

[0053] Specifically, the extrusion material, after mixing PVB resin particle matrix with nano-inorganic heat insulation particles, is fed into the extrusion cylinder 210 through the feeding unit 500 and heated to melt. The extrusion screw 230 rotates continuously, thereby gradually pushing the molten mixed material towards one end of the extrusion head 410. The suspension sleeve 340 is eccentrically set relative to the extrusion cylinder 210. When the material passes through the eccentric suspension throwing unit 300, the suspension sleeve 340 is driven by the rotating cylinder 320 to continuously circumferentially eccentrically swing relative to the extrusion cylinder 210, thereby causing the radial distance between the suspension sleeve 340 and the extrusion screw 230 at different positions to change periodically. The eccentrically moving suspension sleeve 340 periodically throws the nano-inorganic heat insulation particles that gradually sink to the bottom of the extrusion cylinder 210 upwards and performs all-round extrusion and dispersion of the material in the extrusion cylinder 210, thereby improving the dispersion effect of nano-inorganic heat insulation particles and PVB resin particle matrix.

[0054] Subsequently, the raw material is extruded from the outlet of the extruder head 410 through the extrusion channel 421. During the process of the raw material passing through the extrusion channel 421, the cross-sectional area of ​​the extrusion channel 421 is dynamically changed by the periodic contraction and expansion motion of the radial expansion member. During the contraction phase, the flow velocity increases, which rolls up the deposited particles. During the expansion phase, turbulence is generated, which promotes the dispersion of the raw material.

[0055] It should be noted that the PVB melt has high viscosity, which enables the melt to effectively convert the mechanical motion of the suspension sleeve 340 into the transmission of volume force. During the eccentric extrusion process of the suspension sleeve 340, the high viscosity melt is not prone to local slippage and can uniformly transmit the extrusion stress to the nanoparticles deposited at the bottom, forcing them to move with the melt.

[0056] The extrusion screw 230 continuously rotates to push the material, while the suspension sleeve 340 performs radial eccentric oscillation. The two movements are orthogonal, forming a three-dimensional flow field with superposition of axial pushing and radial disturbance. At the bottom of the screw groove, the area that was originally prone to forming a stagnant layer is constantly disturbed by the periodic extrusion of the suspension sleeve 340, and the deposited particles are forced into the mainstream area, thereby eliminating the formation of agglomerates.

[0057] In high-viscosity PVB melt, the sedimentation behavior of nanoparticles is not instantaneous, but rather a gradual enrichment caused by dead or low-velocity flow zones. The eccentric oscillation of the suspension sleeve 340 does not rely solely on mechanical impact to disperse the particles, but rather generates dynamic compression and release in the melt by periodically changing the radial gap, forming a flow field with alternating local high and low pressures. In this process, the high-viscosity melt can effectively transfer momentum, forcibly entraining the particles deposited at the bottom into the mainstream area, thereby achieving uniform dispersion.

[0058] In high-viscosity melts, the settling velocity of nanoparticles is much lower than that in low-viscosity media. This is a local enrichment phenomenon caused by dead zones in the flow of nanoparticles in high-concentration, high-viscosity systems, rather than rapid settling caused by gravity. Therefore, the periodic intervention of the suspension sleeve 340 is sufficient to redisperse the particles back into the melt before they form hard agglomerates. In addition, after the melt is initially dispersed by the eccentric suspension throwing unit 300, it will undergo periodic contraction and expansion of the radial expansion member after entering the variable cross-section flow channel unit 400, generating local high-speed flow and turbulence, further entraining residual deposited particles and promoting micro-mixing.

[0059] It is worth noting that the present invention drives the suspension sleeve 340 to periodically eccentrically swing within the extrusion cylinder 210 by rotating the cylinder 320, which forces the nano-inorganic heat insulation particles that have settled to the bottom to be continuously thrown upwards, directly destroying the particle deposition environment, thereby eliminating the formation of instantaneous high-concentration agglomerate pulses and avoiding defects such as crystal points and fish eyes in the subsequent high heat insulation PVB film.

[0060] The continuous oscillation of the suspension sleeve 340 effectively removes the stagnant layer formed by the deposition of nanoparticles at the bottom of the screw groove, eliminating the long-term adhesion and compaction of microparticles in the dead corner of the micro-zone eddy. This not only avoids uneven radial wear caused by the peeling off of the deposit layer and scratching the inner wall of the extrusion cylinder 210, but also ensures the high stability of the extrusion pressure during long-term continuous operation of the equipment.

[0061] In the extrusion channel 421 formed by the extruder head 410 and the guide core 420, the periodic contraction and expansion motion of the radial expander creates a dynamic variable pressure control environment. The high flow rate during the contraction phase rolls up the deposited particles, and the micro-turbulence during the expansion phase promotes uniform dispersion. When the melt after upstream dispersion treatment passes through the screen changer, the absence of high-intensity agglomerate pulses effectively avoids local fatigue fracture of the filter screen.

[0062] In one embodiment, please refer to Figure 4 The spiral extrusion unit 200 also includes a drive motor 220 fixedly installed at one end of the extrusion cylinder 210. The output end of the drive motor 220 is connected to the extrusion screw 230. The extrusion screw 230 is provided with spiral extrusion blades 240 adapted to the inside of the extrusion cylinder 210.

[0063] Specifically, by driving the extrusion screw 230 to rotate continuously by the drive motor 220, the spiral extrusion blades 240 of the extrusion screw 230 can be used to spirally push the mixed raw materials in the extrusion cylinder 210. Combined with the eccentric extrusion of the eccentric suspension throwing unit 300 and the periodic contraction and expansion of the variable cross-section flow channel unit 400, the raw materials are evenly dispersed and extruded from the outlet of the extrusion head 410.

[0064] It should be noted that the drive motor 220 provides continuous and stable rotational power to the extrusion screw 230, driving the spiral extrusion blades 240 to perform basic spiral pushing of the molten raw material. This forms a temporal coupling with the periodic eccentric extrusion of the eccentric suspension throwing unit 300 and the dynamic expansion and contraction of the cross-section of the variable cross-section flow channel unit 400, so that the raw material repeatedly experiences the composite action field of conveying-throwing-pressure changing during the forward movement, effectively improving the dispersion effect.

[0065] By driving the constant speed of the drive motor 220, the extrusion screw 230 is ensured to provide a stable material base for the radial oscillation of the suspension sleeve 340 while completing the axial conveying. This allows the nanoparticles to be subjected to forced dispersion forces in three dimensions: axial propulsion, radial throwing, and circumferential turbulence, effectively eliminating the physical defect of high-hardness particles settling to the bottom due to their large inertia.

[0066] The continuous power output of the drive motor 220 ensures the pressure continuity of the melt as it passes through the eccentric suspension throwing unit 300 and the variable cross-section flow channel unit 400. Even when the suspension sleeve 340 is oscillating and the cross-section of the extrusion channel 421 changes periodically, the forced pushing of the spiral extrusion blades 240 can still maintain the basic stability of the extrusion pressure, which not only ensures the dispersion effect but also avoids the drastic pressure fluctuations caused by sudden changes in the flow channel.

[0067] Further, please refer to Figure 5 and Figure 6 The eccentric suspension throwing unit 300 also includes a sealing ring 310 fixed to the inner wall of both ends of the extrusion cylinder 210 corresponding to the rotating cylinder 320. The sealing ring 310 is used to axially limit both ends of the suspension sleeve 340. A lubrication cavity 330 is formed between the suspension sleeve 340 and the rotating cylinder 320. The two ends of the lubrication cavity 330 are respectively connected to an inlet pipe 331 and a drain pipe 332.

[0068] Specifically, the sealing rings 310 at both ends prevent the suspension sleeve 340 from axially moving during eccentric swing. The lubrication cavity 330 is filled with thermally conductive lubricating fluid, thereby reducing the resistance of the suspension sleeve 340 during eccentric swing. At the same time, the heated thermally conductive lubricating fluid is introduced into the lubrication cavity 330 through the inlet pipe 331. The molten raw material in the extrusion cylinder 210 is heated by the thermally conductive lubricating fluid. The thermally conductive lubricating fluid after heat exchange is discharged through the drain pipe 332.

[0069] It is worth noting that the sealing ring 310 is fixed to the inner wall of both ends of the extrusion cylinder 210 to axially limit the suspension sleeve 340, effectively eliminating the axial movement that may occur during high-speed eccentric swing, ensuring that the periodic change of the radial distance between the suspension sleeve 340 and the extrusion screw 230 strictly follows the preset trajectory, thereby achieving uniform and stable periodic throwing of nanoparticles that have settled to the bottom, eliminating the dispersion blind zone caused by mechanical displacement, and ensuring the uniform distribution of heat-insulating particles in the PVB melt;

[0070] The lubrication cavity 330 is formed between the suspension sleeve 340 and the rotating cylinder 320. The heat-conducting lubricating fluid filled inside forms a stable dynamic oil film when the two move relative to each other, thereby greatly reducing the frictional resistance and contact stress during eccentric oscillation, reducing mechanical wear and energy loss, and enabling the equipment to withstand the intense movement under the condition of high hardness nanoparticles for a long time.

[0071] Heated thermally conductive lubricating fluid is introduced through the inlet pipe 331. Circulation within the lubrication chamber 330 provides continuous lubrication to the moving parts and directly heats the molten material in the extrusion cylinder 210 in a non-contact, uniform manner. The lubricating fluid, after heat exchange, is discharged and recycled through the outlet pipe 332. By combining the lubricating medium and the heat transfer medium, efficient and uniform heat transfer from the lubricating fluid to the melt is achieved, improving the accuracy and response speed of temperature control and providing an ideal thermodynamic environment for the stable extrusion of high-insulation PVB films.

[0072] Furthermore, please refer to Figure 5 , Figure 6 and Figure 7 A rotary motor 350 is fixedly installed on the frame 100. A rotary gear 360 is connected to the output end of the rotary motor 350. A rotary gear ring 370 that meshes with the rotary gear 360 is provided on the outside of the rotating drum 320. A protruding rib 380 that abuts against the suspension sleeve 340 is provided inside the rotating drum 320.

[0073] Specifically, the rotary motor 350 drives the rotary gear 360 to rotate. Under the meshing transmission of the rotary gear 360 and the rotary gear ring 370, the rotating drum 320 is driven to rotate continuously in the circumferential direction relative to the extrusion cylinder 210. During the rotation of the rotating drum 320, the protruding ribs 380 inside it also move in the circumferential direction in sync. The protruding ribs 380 push the suspension sleeve 340 at different positions, thereby driving the suspension sleeve 340 to swing eccentrically inside the extrusion cylinder 210 to push the molten material inside the extrusion cylinder 210 and prevent nanoparticles from depositing at the bottom of the extrusion cylinder 210.

[0074] It should be noted that during the circumferential rotation of the rotating drum 320, the protruding ribs 380 inside the drum periodically abut and push against different positions of the suspension sleeve 340, so that the suspension sleeve 340 generates a continuous, smooth and impact-free eccentric oscillation trajectory in the extrusion cylinder 210, avoiding material impact or dispersion dead zones that may be caused by intermittent drive, and continuously and evenly throwing the nanoparticles deposited at the bottom back to the mainstream of the melt, effectively eliminating the conditions for the formation of agglomerates.

[0075] The rotating gear ring 370 drives the rotating drum 320 to rotate continuously, causing the pushing action point of the protrusion 380 to move cyclically along the circumferential surface of the suspension sleeve 340, realizing dynamic intervention of the melt inside the extrusion cylinder 210 in the whole circumference. No matter where the nanoparticles settle to the bottom of the cylinder due to inertia or gravity, they will be effectively captured and lifted up again by the circumferential pushing action.

[0076] In yet another embodiment, please refer to Figure 8 The core 420 is coaxially fixed inside the extrusion head 410 by a number of circumferentially distributed fixing posts 430. The core 420 is provided with an arc-shaped recess 440, and the radial expansion member is located at the arc-shaped recess 440.

[0077] Furthermore, the radial expansion member includes a radial expansion bladder 450 disposed on the inner wall of the extrusion head 410 and adapted to the arc-shaped recess 440, and the extrusion head 410 is provided with an air nozzle 460 communicating with the interior of the radial expansion bladder 450.

[0078] Specifically, high-pressure gas is periodically introduced and extracted into the radial expansion bladder 450 through the air nozzle 460, thereby causing the radial expansion bladder 450 to periodically expand and contract. The radial expansion motion of the radial expansion bladder 450 is used to radially squeeze and release the raw material flowing through the extrusion channel 421, thereby promoting the full integration of nanoparticles and the matrix.

[0079] It is worth noting that by using several circumferentially distributed fixed columns 430 to coaxially fix the flow core 420 inside the extrusion head 410, the gap height of the extrusion channel 421 is consistent throughout the entire circumferential direction, eliminating the uneven flow velocity distribution caused by eccentricity or deformation, so that the melt forms a stable circumferential flow field before entering the variable cross-section control area, providing a uniform material basis for subsequent dynamic dispersion.

[0080] High-pressure gas is periodically introduced and extracted into the radially expanding capsule 450 located in the arc-shaped recess 440 through the air nozzle 460, driving the capsule to perform regular expansion and contraction movements, thus achieving non-contact dynamic control of the high-temperature and high-pressure melt flow channel. When expanding, the radially expanding capsule 450 expands radially towards the arc-shaped recess 440, implementing uniform annular extrusion of the melt in the extrusion channel 421; when contracting, it rapidly releases the flow channel space. The narrowing of the cross section during the expansion stage causes a sharp increase in flow velocity, forming a strong stretching flow to break up soft agglomerates; the expansion of the cross section during the contraction stage induces microscopic turbulence, promoting the uniform distribution of nanoparticles; the alternating radial extrusion also forces the melt to repeatedly undergo stretching and relaxation, effectively strengthening the interfacial fusion between PVB molecular chains and nanoparticles.

[0081] The arc-shaped recess 440 provided on the core 420 provides a specific working space for the radial expansion bladder 450. This recessed structure forms a local low-pressure zone when the bladder contracts and forms a constricted flow channel together with the bladder when it expands. This abrupt change and recovery of the flow channel geometry prolongs the working time of the melt in the variable cross-section region, so that each radial extrusion can effectively intervene in a larger volume of melt, thereby maximizing the dispersion effect in a limited space and improving the unit energy consumption efficiency of the equipment.

[0082] Furthermore, please refer to Figure 8 The drainage core 420 has several sets of U-shaped channels 470 arranged in the inner circumference. Both ends of the U-shaped channels 470 are provided with connecting holes 480. The fixing posts 430 at both ends of the U-shaped channels 470 are provided with connecting nozzles 490 that communicate with their respective connecting holes 480.

[0083] Specifically, heat transfer oil is injected into the corresponding core 420 through one end connector 490. When the heat transfer oil flows through the U-shaped flow channel 470, it heats the raw material in the extrusion flow channel 421. Then, the heat-exchanged heat transfer oil flows out through the opposite connector 490.

[0084] It should be noted that several sets of U-shaped flow channels 470 are evenly distributed circumferentially inside the flow core 420. Through the circulation of heat transfer oil, the molten raw material in the extrusion flow channel 421 is uniformly heated in the entire circumference, ensuring that the melt viscosity at any position on the circumference of the flow channel is highly consistent, and eliminating uneven dispersion caused by local temperature differences.

[0085] The U-shaped flow channel 470's orientation design allows the heat transfer oil to flow back and forth inside the core 420, extending the heat exchange path and contact time between the heat transfer oil and the core. This enables the heat transfer oil per unit flow rate to release more heat energy, significantly improving heat exchange efficiency and energy utilization.

[0086] High-temperature heat transfer oil is injected through one end connector 490, flows through the U-shaped flow channel 470 for full heat exchange, and then flows out through the opposite connector 490, forming an independent circulation loop with completely separated inlet and outlet. This avoids the mixing and interference of hot and cold fluids, ensuring that the flow core 420 is always in a stable temperature field. Combined with the dynamic control of the radial expansion bladder 450, the melt is always in the optimal processing temperature range while undergoing periodic changes in the flow channel cross-section, improving process repeatability and product yield.

[0087] The connecting hole 480 is located at the fixed post 430, which integrates the inlet and outlet channels of the heat transfer oil with the core fixing structure, reducing the need for additional interfaces on the extrusion head 410 housing, avoiding potential leakage risks, and is completely independent of the melt flow channel. This ensures the heating effect and eliminates the possibility of heat transfer oil leakage contaminating the PVB product.

[0088] In further embodiments, please refer to Figure 2 , Figure 3 and Figure 4 The feeding unit 500 includes a hopper 510 connected to the inlet end of the extrusion cylinder 210. Rotating shafts 520 are symmetrically mounted on both sides of the hopper 510. A lever 530 is mounted on each rotating shaft 520. Each of the two sets of rotating shafts 520 is equipped with a meshing driven gear 540. A drive gear 550 is sleeved on the extrusion screw 230. An intermediate gear 560 is rotatably mounted on the outer wall of the hopper 510, meshing with the drive gear 550. The intermediate gear 560 meshes with one of the sets of driven gears 540.

[0089] Specifically, during the process of the drive motor 220 driving the extrusion screw 230, the drive gear 550 drives the intermediate gear 560 to rotate, thereby driving one set of driven gears 540 to rotate. Then, through the meshing action of the driven gears 540 on both sides, the two sets of rotating shafts 520 are driven to rotate synchronously. The paddle plate 530 on the rotating shaft 520 can be used to paddle and disperse the mixed raw materials in the hopper 510.

[0090] It should be noted that the power is transmitted to the rotating shaft 520 through the drive gear 550 sleeved on the extrusion screw 230, the intermediate gear 560 and the driven gear 540 in sequence, so that the feeding action of the feed plate 530 is related to the rotation speed of the extrusion screw 230 in real time.

[0091] Two sets of rotating shafts 520 are equipped with meshing driven gears 540. Through the unilateral drive of the intermediate gear 560, the synchronous reverse rotation of the two side plates 530 can be achieved, so that the mixed raw materials in the hopper 510 are subjected to alternating pushing forces from the left and right sides, forming a forced convection circulation. This completely eliminates the material segregation and bridging phenomena commonly found in traditional unilateral pushing or free fall feeding, ensuring that PVB resin particles and nano heat insulation particles always remain in a uniform mixing state before entering the extrusion section.

[0092] In view of the fact that the specific gravity of the nano-inorganic heat insulation particles is much greater than that of the PVB resin matrix, the continuous agitation of the agitator 530 in the hopper 510 applies forced disturbance to the material. This dynamic intervention prevents the high-hardness nanoparticles from settling to the bottom of the hopper 510 in the gravitational field in advance, and keeps them in a suspended state to enter the extrusion cylinder 210 together with the resin particles, thus reducing the load on the subsequent dispersion unit.

[0093] Further, please refer to Figure 10 and Figure 11 The rotating shaft 520 has a central chamber 521 inside, and a permeable membrane 522 communicating with the inside of the hopper 510 is embedded in the central chamber 521. A bearing seat 570 is fixedly installed on the outside of the hopper 510. One end of the rotating shaft 520 is rotatably sleeved in the bearing seat 570. An annular transition chamber 571 is opened in the bearing seat 570. An infusion tube 580 communicating with the annular transition chamber 571 is provided on the outside of the bearing seat 570. A connecting cavity 523 communicating with the central chamber 521 is opened at one end of the rotating shaft 520. Several through holes 524 communicating with the annular transition chamber 571 are opened circumferentially on the inner wall of the connecting cavity 523.

[0094] Specifically, plasticizer is introduced into the annular transition chamber 571 through the infusion tube 580. Subsequently, the plasticizer enters the central chamber 521 through the through hole 524 and the connecting cavity 523. Finally, the plasticizer extends circumferentially into the hopper 510 from the permeation membrane 522 and mixes thoroughly with the raw material. The plasticizer can be continuously added while the material is being fed by the pusher plate 530, so that the plasticizer and nanoparticles are fully impregnated, avoiding the plasticizer being preferentially absorbed and expanded by the PVB resin to form a non-uniform shell.

[0095] It is worth noting that the plasticizer is injected into the annular transition chamber 571 through the infusion tube 580, enters the central chamber 521 of the rotating shaft 520 through the through hole 524 and the connecting cavity 523, and finally permeates into the hopper 510 from the rotating permeation membrane 522, so that the addition of plasticizer is completely synchronized with the feeding action of the push plate 530.

[0096] The permeation membrane 522 rotates synchronously with the rotating shaft 520, and the plasticizer permeates uniformly from its circumferential surface, forming a diffuse droplet field in the hopper 510. This allows the high specific surface area nano-inorganic heat insulation particles to be fully wrapped and wetted by the plasticizer droplets in a suspended state, avoiding local over-concentration or wettability blind spots. By continuously feeding plasticizer while the material is being fed by the push plate 530, the nanoparticles and PVB resin are in an equal window of opportunity to contact the plasticizer. The nanoparticles preferentially adsorb plasticizer molecules due to their high specific surface area, forming a uniform liquid phase coating layer. This effectively inhibits the unidirectional migration of plasticizer to the PVB matrix, eliminating the hard core-soft shell heterogeneous structure caused by preferential swelling of PVB from the source.

[0097] The rotary sealing conveying structure formed by the annular transition chamber 571 and the through hole 524 enables the plasticizer to be stably delivered to the central chamber 521 while the rotating shaft 520 continues to rotate, which not only ensures the continuity of the injection process, but also avoids the defects of leakage and blockage.

[0098] The present invention also provides a method for producing high-insulation PVB interlayer film using extrusion equipment, comprising the following steps:

[0099] Step 1: The mixture of PVB resin and nano heat insulation particles is fed into the extrusion cylinder 210 through the feeding unit 500, heated and melted, and then continuously pushed towards the extrusion head 410 by the extrusion screw 230.

[0100] Step 2: Drive the suspension sleeve 340 to oscillate radially eccentrically through the rotating drum 320, periodically throwing the nanoparticles deposited at the bottom upwards and extruding the melt in all directions.

[0101] Step 3: When the raw material flows through the extrusion channel 421, gas is periodically introduced and extracted through the air nozzle 460, causing the radial expansion member to periodically contract and expand, dynamically changing the cross-sectional area of ​​the channel. The increased flow velocity in the contraction section rolls up the deposited particles, while the turbulence generated in the expansion section promotes further mixing.

[0102] Step 4: The fully dispersed raw material is extruded from the outlet of extruder 410.

[0103] The specific embodiments of the present invention have been described above. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention, all of which are within the protection scope of the present invention.

Claims

1. An extrusion apparatus for producing high-insulation PVB interlayer film, characterized in that, include: Rack (100); The spiral extrusion unit (200) is mounted on the frame (100) and includes an extrusion cylinder (210) fixed on the frame (100) and an extrusion screw (230) rotatably mounted inside the extrusion cylinder (210). An eccentric suspension throwing unit (300) is disposed in the middle section of the extrusion cylinder (210) and includes a rotating cylinder (320) rotatably connected to the extrusion cylinder (210) and a suspension sleeve (340) eccentrically and movably embedded in the rotating cylinder (320). A variable cross-section flow channel unit (400) is disposed at the outlet end of the extrusion barrel (210), including an extrusion head (410) detachably connected to the extrusion barrel (210) and a flow guide core (420) coaxially fixed inside the extrusion head (410). An extrusion flow channel (421) is formed between the extrusion head (410) and the flow guide core (420), and a radial expansion member is disposed inside the extrusion flow channel (421). The feeding unit (500) is located at the inlet end of the extrusion cylinder (210) and is used to feed extruded raw materials into the extrusion cylinder (210); The spiral extrusion unit (200) also includes a drive motor (220) fixedly installed at one end of the extrusion cylinder (210). The output end of the drive motor (220) is connected to the extrusion screw (230). The extrusion screw (230) is provided with spiral extrusion blades (240) adapted to the inside of the extrusion cylinder (210). The eccentric suspension throwing unit (300) also includes a sealing ring (310) fixed to the inner wall of both ends of the extrusion cylinder (210) corresponding to the rotating cylinder (320). The sealing ring (310) is used to axially limit both ends of the suspension sleeve (340). A lubrication cavity (330) is formed between the suspension sleeve (340) and the rotating cylinder (320). The two ends of the lubrication cavity (330) are respectively connected to an inlet pipe (331) and a drain pipe (332). A rotary motor (350) is fixedly installed on the frame (100). A rotary gear (360) is connected to the output end of the rotary motor (350). A rotary gear ring (370) that meshes with the rotary gear (360) is provided on the outside of the rotating drum (320). A protruding rib (380) that abuts against the suspension sleeve (340) is provided inside the rotating drum (320). The drainage core (420) is coaxially fixed inside the extrusion head (410) by a number of circumferentially distributed fixing columns (430). The drainage core (420) is provided with an arc-shaped recess (440), and the radial expansion member is located at the arc-shaped recess (440). The radial expansion member includes a radial expansion bladder (450) disposed on the inner wall of the extruder (410) and adapted to the arc-shaped recess (440), and the extruder (410) is provided with an air nozzle (460) communicating with the interior of the radial expansion bladder (450).

2. The extrusion equipment for producing high-insulation PVB interlayer film according to claim 1, characterized in that, The drainage core (420) has several sets of U-shaped channels (470) arranged in the inner circumference. Both ends of the U-shaped channels (470) are provided with connecting holes (480). The fixing posts (430) at both ends of the U-shaped channels (470) are provided with connecting nozzles (490) that communicate with their respective connecting holes (480).

3. The extrusion equipment for producing high-insulation PVB interlayer film according to claim 1, characterized in that, The feeding unit (500) includes a hopper (510) connected to the inlet end of the extrusion cylinder (210). The hopper (510) has symmetrical rotating shafts (520) mounted on both sides. The rotating shafts (520) are equipped with a lever plate (530). Both sets of rotating shafts (520) are equipped with mutually meshing driven gears (540). The extrusion screw (230) is fitted with a drive gear (550). The outer wall of the hopper (510) is rotatably mounted with an intermediate gear (560) that meshes with the drive gear (550). The intermediate gear (560) meshes with one of the sets of driven gears (540).

4. The extrusion equipment for producing high-insulation PVB interlayer film according to claim 3, characterized in that, The rotating shaft (520) has a central chamber (521) inside, and a permeation membrane (522) communicating with the inside of the hopper (510) is embedded in the central chamber (521); a bearing seat (570) is fixedly installed on the outside of the hopper (510), and one end of the rotating shaft (520) is rotatably sleeved in the bearing seat (570). An annular transition chamber (571) is opened in the bearing seat (570), and an infusion tube (580) communicating with the annular transition chamber (571) is provided on the outside of the bearing seat (570); a connecting cavity (523) communicating with the central chamber (521) is opened at one end of the rotating shaft (520), and several through holes (524) communicating with the annular transition chamber (571) are opened circumferentially on the inner wall of the connecting cavity (523).

5. A method for producing high-insulation PVB interlayer film using the extrusion equipment according to any one of claims 1-4, characterized in that, Includes the following steps: Step 1: The mixture of PVB resin and nano heat insulation particles is fed into the extrusion cylinder (210) through the feeding unit (500), heated and melted, and then continuously pushed towards the extrusion head (410) by the extrusion screw (230); Step 2: Drive the suspension sleeve (340) to swing radially eccentrically through the rotating drum (320), periodically throwing the nanoparticles deposited at the bottom upwards and extruding the melt in all directions; Step 3: When the raw material flows through the extrusion channel (421), gas is periodically introduced and extracted through the air nozzle (460), causing the radial expansion member to periodically contract and expand, dynamically changing the cross-sectional area of ​​the channel. The flow velocity in the contraction section increases and rolls up the deposited particles, while the expansion section generates turbulence to promote further mixing. Step 4: The fully dispersed raw material is extruded from the outlet of the extruder (410).

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