Polymer volatile component removal device

Abstract

The invention relates to the technical field of polymer volatile component removal, and particularly discloses a polymer volatile component removal device which comprises a barrel, a feed liquid distribution cavity formed in the top of the barrel, a mounting shaft arranged in the axial direction of the barrel and a scraper blade. A plurality of feeding holes communicated with the interior of the barrel are uniformly formed in the circumferential direction of the feed liquid distribution cavity, a plugging ring is rotationally arranged in the feed liquid distribution cavity, plugging holes matched with the feeding holes are formed in the plugging ring, the interior of the mounting shaft is hollow, a driving shaft is coaxially arranged in the mounting shaft, and the driving shaft is in threaded connection with the mounting shaft; the driving shaft can lift and move in the axial direction when rotating; the driving shaft is connected with the plugging ring through a connecting mechanism, so that the driving shaft drives the plugging ring to rotate synchronously when rotating, and a plurality of hollow mounting rods are spirally arranged on the periphery of the mounting shaft; according to the invention, self-adaptive adjustment aiming at the viscosity characteristic of the polymer is realized, and the problem that the feeding viscosity is difficult to adapt to the scraper blade is solved.

Description

Technical Field

[0001] This invention relates to the field of polymer volatile matter removal technology, and more specifically to a polymer volatile matter removal device. Background Technology

[0002] During polymer synthesis or post-processing, residual unreacted monomers, organic solvents, moisture, oligomers, and other volatiles not only affect the physical and mechanical properties and electrical properties of the product, but may also generate odors and precipitate during subsequent processing or use, causing pollution or safety hazards. Therefore, reducing the volatile content to extremely low levels (typically requiring ppm levels) is a crucial step in obtaining high-quality polymer products. Traditional polymer devolatilization methods mainly include hot air drying ovens, vacuum ovens, and screw extruder devolatilization. Hot air drying and vacuum ovens are intermittent operations, resulting in low production efficiency, high energy consumption, large footprint, high labor intensity, and a tendency to cause uneven heating of the polymer, leading to localized degradation.

[0003] Chinese patent document CN113908573B discloses a novel scraper-type thin-film evaporator, comprising: a connecting shaft, a drive motor, a vacuum connection port, a scraper device, a heating pipe, a connecting bearing, a base, a bottom connecting shaft, an electric cylinder, a housing, a material distribution plate, a feed pipe, and an upper cover; the base is fixedly installed inside the housing; the base is fixedly connected to the outer ring of the connecting bearing; one end of the bottom connecting shaft is fixedly connected to the inner ring of the connecting bearing, and the other end is fixedly connected to the scraper device; there are at least two sets of scraper devices, and the two sets are connected by an electric cylinder; the material distribution plate is fixedly installed on the scraper device at the upper end; one end of the connecting shaft is fixedly installed on the material distribution plate, and the other end is fixedly connected to the output shaft of the drive motor; the upper cover is fixedly installed on the upper side of the housing; the main body of the drive motor is fixedly installed on the upper cover; the feed pipe is fixedly installed on one side of the housing; the vacuum connection port is fixedly installed on one side of the upper cover, located away from the feed pipe; and the heating pipe is fixedly installed on the side of the housing.

[0004] In the aforementioned technical solution, the scraper device and feeding disc are used to adjust the distance between the scraper and the box according to the different polymers being processed. Furthermore, the scraper can be pushed against the inner wall of the box according to the required degree of drying for different polymers. This allows the patented technology to process polymers with high water content and high viscosity that are difficult to form a film within a limited space. However, different types of polymers, or even the same polymer at different devolatilization stages, exhibit vastly different viscosities (ranging from hundreds to millions of centipoises). For low-viscosity fluids, a smaller gap and a faster rotation speed are required to maintain a stable liquid film. For high-viscosity melts, if the gap is too small or the scraper rigidity is too high, the enormous shear resistance will overload the motor, and the material will easily accumulate at the leading edge of the scraper, failing to form a uniform film. Although some equipment attempts to introduce elastic scrapers, their elasticity coefficient is usually fixed, unable to simultaneously meet the wall-adhering requirements for low viscosity and the avoidance requirements for high viscosity. Moreover, the control of the feed flow rate is usually independent of the scraper rotation speed, lacking a linkage mechanism. When processing high-viscosity materials, it is usually necessary to reduce the feed rate to ensure sufficient residence time and devolatilization effect. However, existing equipment often requires independent adjustment of the feed pump and scraper motor, which is cumbersome and difficult to achieve the best matching state. Summary of the Invention

[0005] This invention provides a polymer volatile matter removal device, which aims to solve the problems of existing scraper-type volatile matter removal equipment being unable to adapt to materials with a wide viscosity range, having unstable film thickness control, and having difficulty matching operating parameters.

[0006] A polymer volatile matter removal device includes: a cylindrical body, a liquid distribution chamber disposed at the top of the cylindrical body, a mounting shaft disposed along the axial direction of the cylindrical body, and a scraper; a plurality of feed holes communicating with the interior of the cylindrical body are evenly arranged circumferentially along the liquid distribution chamber; a sealing ring is rotatably disposed within the liquid distribution chamber, and the sealing ring has sealing holes adapted to the feed holes; the overlap between the feed holes and the sealing holes is adjusted by rotating the sealing ring; the mounting shaft is hollow inside, and a drive shaft is coaxially disposed inside the mounting shaft; the drive shaft is threadedly connected to the mounting shaft, so that the drive shaft can move up and down axially when rotating; a drive component for driving the drive shaft to rotate is mounted on the cylindrical body; the drive shaft is connected to the sealing ring through a connecting mechanism, so that the drive... When the rotating shaft rotates, it drives the sealing ring to rotate synchronously; several hollow mounting rods are spirally arranged on the outer circumference of the mounting shaft, and a rotating shaft and a pushing shaft are coaxially arranged inside the mounting rods; the scraper is connected to one end of the rotating shaft near the inner wall of the cylinder; an elastic element is installed between the rotating shaft and the pushing shaft to generate elastic potential energy when the two rotate relative to each other; a connecting assembly is installed between the pushing shaft and the driving shaft, configured to drive the pushing shaft to rotate relative to the mounting rods when the driving shaft moves axially up and down, thereby adjusting the preload of the elastic element; a guide assembly is provided between the rotating shaft and the mounting rods, configured to guide the rotating shaft to generate radial displacement when the rotating shaft is subjected to force and rotates, thereby adjusting the distance between the scraper and the inner wall of the cylinder.

[0007] Its effect is as follows: This solution constructs a single-power-source, multi-parameter linkage mechanical system. When the drive shaft rotates, due to the threaded connection, the drive shaft undergoes axial lifting and lowering while rotating. The rotational motion of the drive shaft is directly transmitted to the sealing ring, changing the effective flow area of ​​the feed hole. The axial lifting and lowering motion of the drive shaft is converted into the rotation of the internal drive shaft of the mounting rod through the connecting assembly. The rotation of the drive shaft compresses or relaxes the elastic element, changing the "hardness" of the scraper system. The material resistance encountered by the scraper during operation acts on the rotating shaft. The guide assembly forces the rotating shaft to undergo radial displacement (changing the gap) when it rotates under force, while the elastic element provides the restoring force. The device achieves "one-click" adaptive adjustment based on the viscosity characteristics of polymers. When processing high-viscosity materials, the device can automatically adjust to: a large feed orifice diameter (reducing flow resistance), a high elastic element pre-tightening force (preventing the scraper from being blocked by the material and unable to scrape the film), and a large base gap with automatic retraction function. When processing low-viscosity materials, the device automatically adjusts to: a small feed orifice diameter (controlling the flow rate to prevent flooding), a low elastic element pre-tightening force (flexible contact), and a small base gap. This solves the problems of traditional equipment where the feed and scraper adjustments are separate, the operation is cumbersome, and it is difficult to match the optimal process parameters.

[0008] Preferably, the driving component is a servo motor, and the drive shaft is connected to the output end of the servo motor. An internal thread is formed on the inner wall of the mounting shaft, and an external thread is formed on the outer surface of the drive shaft. The internal and external threads mesh with each other to achieve axial linear motion of the drive shaft while it rotates. The servo motor is configured to rotate in both directions to control the lifting and lowering direction of the drive shaft. The servo motor provides precise rotation angle control, accurately converting rotational motion into axial linear displacement of the drive shaft through a screw drive principle (lead screw and nut pair principle). The forward and reverse rotation of the servo motor corresponds to the rising and falling of the drive shaft, thus corresponding to the switching of different working modes. The structure is compact, and complex motion synthesis is achieved using simple mechanical principles. The introduction of the servo motor makes the adjustment process digital and precise, avoiding the risk of media contamination associated with hydraulic or pneumatic adjustment, making it suitable for the production of high-purity polymers.

[0009] Preferably, the connecting mechanism includes a connecting rod, a groove formed on the outer periphery of the drive shaft, and a slider disposed within the groove; the groove extends axially along the drive shaft, and the slider is slidably disposed within the groove; one end of the connecting rod is hinged to the sealing ring, and the other end is hinged to the slider; when the drive shaft rotates, the slider and connecting rod rotate through the groove, thereby causing the sealing ring to rotate; when the drive shaft rises or falls, the slider slides relative to the groove to compensate for axial displacement; the groove and the slider constitute a coupling mechanism capable of transmitting torque but allowing free axial movement. When the drive shaft rotates, the sidewall of the groove pushes the slider to rotate; when the drive shaft rises or falls, the groove slides over the slider, cleverly resolving the motion contradiction between the drive shaft "rotating and rising / falling simultaneously" and the sealing ring "only rotating and not rising / falling." This avoids structural damage or sealing failure caused by the forced pulling of the sealing ring due to the rise and fall of the drive shaft, ensuring the smoothness and reliability of the feeding adjustment mechanism.

[0010] Preferably, a first baffle is fixedly mounted on the rotating shaft, and a second baffle is fixedly mounted on the pushing shaft. The elastic element is a torsion spring or a cylindrical helical compression spring. One end of the elastic element is connected to the first baffle, and the other end is connected to the second baffle. By changing the angular position of the pushing shaft relative to the rotating shaft, the relative distance or angle between the first and second baffles can be changed, thereby compressing or relaxing the elastic element. The rotation of the pushing shaft changes the relative position of the first and second baffles, thereby changing the deformation (length or torsion angle) of the elastic element sandwiched in between. According to Hooke's Law, the change in deformation directly leads to a change in the magnitude of the elastic force, realizing stepless adjustment of the scraper contact pressure (or stiffness). This allows the device to gently handle low-viscosity solutions to prevent liquid film rupture, and to powerfully scrape high-viscosity melts to achieve surface renewal, significantly broadening the applicability of the device.

[0011] Preferably, the connecting assembly includes a mounting groove formed on the inner wall of the mounting shaft, a rack slidably disposed within the mounting groove, a gear fixedly disposed at the end of the push shaft, an annular groove formed on the outer periphery of the drive shaft, and a locking block fixedly disposed on one side of the rack; the gear meshes with the rack; the end of the locking block extends into the annular groove, so that when the drive shaft rises and falls, it drives the rack to move up and down, thereby driving the gear and the push shaft to rotate, while the rotation of the drive shaft does not affect the vertical position of the rack; the annular groove allows the drive shaft to rotate without interfering with the locking block, but when the drive shaft rises and falls, it will lock the locking block to drive the rack to rise and fall. The linear motion of the rack drives the gear to rotate through meshing, thereby driving the push shaft to rotate. Within the extremely limited space inside the mounting shaft, the linear motion of the central shaft is converted into the rotational motion of the internal shafts of the surrounding radial mounting rods. This mechanism has high transmission efficiency and good synchronization, ensuring that the elastic coefficient of all scrapers is adjusted completely consistently.

[0012] Preferably, the connecting assembly includes a mounting groove formed on the inner wall of the mounting shaft, a push bar slidably disposed in the mounting groove, an abutment block fixedly disposed on the drive shaft, an annular groove formed on the outer periphery of the drive shaft, and a locking block fixedly disposed on one side of the push bar; the end of the push bar contacts and engages with the end of the abutment block, configured to convert linear motion into rotational thrust; the end of the locking block extends into the annular groove, causing the drive shaft to move when it rises and falls; by utilizing the inclined thrust of the abutment block (such as a wedge block or cam structure) or by directly pushing the eccentric position, the lifting displacement of the drive shaft is converted into the action of the push shaft, providing another high-load-bearing transmission scheme besides gear and rack transmission, with a simpler and more robust structure, suitable for large-size, heavy-load freewheeling equipment, and reducing manufacturing and maintenance costs.

[0013] Preferably, the guiding assembly includes an arc-shaped guide groove formed on the inner wall of the mounting rod and an arc-shaped slider fixed on the rotating shaft; the arc-shaped slider is slidably disposed within the arc-shaped guide groove; the trajectory of the arc-shaped guide groove is configured such that when the rotating shaft rotates along the direction of resistance to the scraper, it guides the rotating shaft to retract away from the inner wall of the cylinder; the guiding assembly defines the movement trajectory of the rotating shaft. When the scraper encounters high-viscosity materials or hard lumps, the resistance forces the rotating shaft to rotate, and the arc-shaped groove forces the rotating shaft to retract (give way) towards the center while rotating, giving the scraper an obstacle avoidance function. This not only protects the scraper and motor from overload damage, but more importantly, through the dynamic balance of resistance and elasticity, it automatically forms the optimal film thickness that matches the material viscosity, greatly improving the stability of the devolatilization process.

[0014] Preferably, the mounting rods are distributed in a multi-headed helical pattern along the outer circumference of the mounting shaft, and the helix angle is configured to generate a downward axial thrust when the scraper coats the polymer. The outer wall of the cylinder is provided with a heating jacket or a heat tracing pipe to control the devolatilization temperature. The rotating helical mounting rods are similar to the blades of a screw pump, generating a downward thrust component on the material they contact, which helps the high-viscosity material flow more smoothly downward in the gravitational field, preventing the material from staying on the cylinder wall for too long, which would lead to thermal degradation or cross-linking, and ensuring the uniformity of product quality.

[0015] Preferably, the bottom of the liquid distribution chamber is funnel-shaped, and the feed inlet is located on the side wall of the funnel-shaped bottom. The sealing ring is fitted against the inner wall of the liquid distribution chamber, and a sealing assembly is provided between the sealing ring and the liquid distribution chamber to prevent polymer liquid from leaking from areas outside the feed inlet. The funnel-shaped design utilizes gravity to collect the material, and the sealing assembly ensures that the fluid can only flow out from the adjusted orifice, improving the accuracy of feed flow control, avoiding "short-circuit" flow, and ensuring that all material entering the cylinder undergoes accurate metering and subsequent sufficient devolatilization.

[0016] Preferably, the device further includes a control unit electrically connected to the drive component. The control unit controls the rotation direction and number of revolutions of the drive component according to the viscosity parameters of the polymer to be processed, thereby synchronously adjusting the feed flow rate, scraper elastic coefficient, and the basic distance between the scraper and the cylinder wall. The control unit receives instructions or sensor feedback, calculates the target speed and position of the servo motor through an algorithm, and automatically executes the adjustment action, realizing the automation and intelligent control of the devolatilization process, reducing the dependence on operator experience, and improving production efficiency and batch stability of product quality.

[0017] By adopting the above technical solution, the beneficial effects of the present invention are as follows: 1. This invention achieves synchronous and coordinated adjustment of feed flow rate, scraper stiffness, and foundation gap through a single drive source. The device can automatically switch modes according to the material viscosity (high viscosity corresponds to high flow rate and high stiffness; low viscosity corresponds to low flow rate and low stiffness), avoiding cumbersome manual adjustment and equipment blockage or incomplete volatilization caused by parameter mismatch; 2. A "resistance-displacement" feedback mechanism was constructed using guide components and elastic elements. When the scraper encounters hard lumps or a sudden increase in resistance, it can automatically retract to avoid overloading the motor or scratching the cylinder wall; it automatically resets after the resistance disappears, ensuring the continuity of the film scraping process and the dynamic stability of the film thickness. 3. The mounting rods are arranged in a spiral shape, generating a downward axial thrust during operation, similar to the principle of a screw pump, forcibly pushing high-viscosity materials downward. This effectively eliminates dead zones in the flow, strictly controls the residence time of materials in the high-temperature zone, and prevents the polymer from yellowing or carbonizing due to prolonged wall adhesion. 4. This invention employs a threaded transmission and a gear and rack (or sliding groove) mechanism to complete the motion conversion from "rotation + lifting" to "rotation + variable stiffness". The transmission components are encapsulated internally, avoiding material contamination, and the structure is compact and easy to maintain. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the cylinder of the present invention.

[0019] Figure 2 This is a schematic diagram of the mounting shaft and drive shaft of the present invention.

[0020] Figure 3 This is a schematic diagram of the connection mechanism of the present invention.

[0021] Figure 4 This is a schematic diagram of the sealing ring and sealing hole of the present invention.

[0022] Figure 5 This is a schematic diagram of the connection component of the present invention.

[0023] Figure 6 This is a schematic diagram of the push shaft, drive shaft, and elastic element of the present invention.

[0024] Figure 7 This is a schematic diagram of another embodiment of the connection component of the present invention.

[0025] Figure 8 This is a schematic diagram of the structure of the guide component of the present invention.

[0026] Figure label: 1. Cylinder; 2. Liquid distribution chamber; 21. Feed hole; 22. Sealing ring; 23. Sealing hole; 3. Mounting shaft; 31. Mounting rod; 32. Rotating shaft; 33. Pushing shaft; 34. Elastic element; 35. First baffle; 36. Second baffle; 4. Scraper; 5. Drive shaft; 6. Drive element; 7. Connecting mechanism; 71. Connecting rod; 72. Slide groove; 73. Slider; 8. Connecting assembly; 81. Mounting groove; 82. Rack; 83. Gear; 84. Annular groove; 85. Locking block; 86. Pushing bar; 87. Abutment block; 9. Guide assembly; 91. Arc-shaped guide groove; 92. Arc-shaped block. Detailed Implementation

[0027] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0028] like Figures 1-8As shown, this embodiment provides a polymer volatile matter removal device. The main body of the device is a vertically placed cylindrical cylinder 1. The cylinder 1 is usually made of corrosion-resistant stainless steel. Its outer wall is covered with a heating jacket or wrapped with a semi-tube heating coil (not shown in detail in the figure) for introducing heat transfer oil or steam to maintain the process temperature required for the devolatification process, ensure that the polymer remains in a molten state and provide the latent heat required for the evaporation of volatile matter.

[0029] A liquid distribution chamber 2 is provided at the top of the cylinder 1. The function of this distribution chamber is to buffer and initially distribute the polymer melt or solution delivered from the upstream reactor or storage tank. To adapt to the flow control requirements under different operating conditions, a ring of feed holes 21 is uniformly formed along the circumferential sidewall or bottom of the liquid distribution chamber 2. These holes connect the interior of the distribution chamber with the working space inside the cylinder 1. A rotatable sealing ring 22 is set close to the inner wall of the distribution chamber. The sealing ring 22 is also an annular component, on which sealing holes 23 are formed, corresponding to the position and shape of the feed holes 21.

[0030] The core moving component of the device is the mounting shaft 3, which is installed along the central axis of the cylinder 1. This mounting shaft 3 is driven to rotate by a motor at the top, driving the scraper 4. However, in this invention, the mounting shaft 3 is not merely a solid drive shaft; it is hollow inside, and its inner wall is machined with internal threads. A drive shaft 5 is coaxially mounted inside the mounting shaft 3, and the outer surface of the drive shaft 5 is machined with external threads that mate with the aforementioned internal threads. A drive component 6, preferably a high-precision servo motor, is installed at the top of the cylinder 1. The output shaft of the servo motor is connected to the internal drive shaft 5. When the servo motor drives the drive shaft 5 to rotate, due to the presence of the threaded pair (assuming the mounting shaft 3 is temporarily relatively stationary, at which point there is a certain frictional resistance between the mounting shaft 3 and the cylinder 1, this frictional resistance keeps the mounting shaft 3 relatively stationary before the drive shaft 5 rotates to its highest or lowest point), the drive shaft 5 will undergo axial lifting and lowering motion relative to the mounting shaft 3. This composite motion of "rotation + lifting" is utilized in this invention to simultaneously achieve multiple adjustment functions.

[0031] To adjust the feed rate using the rotation of the drive shaft 5, the sealing ring 22 is connected to the drive shaft 5 via a special connecting mechanism 7. Since the drive shaft 5 moves up and down during adjustment, while the sealing ring 22 can only rotate on a horizontal plane, a rigid fixed connection cannot be used.

[0032] This embodiment employs the following scheme: Multiple grooves 72 are axially formed on the upper outer periphery of the drive shaft 5. A slider 73, which fits well with the groove 72, is embedded within each groove. The slider 73 can slide freely up and down within the groove 72, but cannot rotate relative to the drive shaft 5. One end of the connecting rod 71 is hinged to the slider 73, and the other end is hinged to the sealing ring 22. The working principle is as follows: When it is necessary to adjust the feed flow rate (e.g., switching from processing low-viscosity materials to high-viscosity materials), the servo motor is activated. The drive shaft 5 rotates, and the thrust of the sidewall of the groove 72 drives the slider 73 to rotate. The slider 73, through the connecting rod 71, drives the sealing ring 22 to rotate within the liquid distribution chamber 2. The rotation of the sealing ring 22 changes the overlapping area of ​​the sealing hole 23 and the feed hole 21. For example, rotating the drive shaft 5 clockwise causes the sealing ring 22 to rotate accordingly, increasing the overlapping area and allowing for smooth feeding, which is suitable for high-viscosity materials. Rotating it counterclockwise reduces the overlapping area, creating a throttling effect, which is suitable for controlling the flow rate of low-viscosity materials. Simultaneously, the drive shaft 5 is undergoing axial displacement (e.g., rising or falling) due to the threaded action. At this time, the relative sliding of the slider 73 within the groove 72 counteracts this axial displacement, ensuring that the sealing ring 22 is not forcibly pulled up or damaged, allowing only pure rotational adjustment.

[0033] Traditional scraper 4 is rigidly fixed to the main shaft by a bracket, while the present invention adopts a "flexible + variable stiffness" support method.

[0034] Several mounting rods 31 are spirally welded or bolted onto the outer circumference of the mounting shaft 3. These mounting rods 31 extend outwards, not only supporting the scraper 4, but their spiral arrangement also resembles a giant screw when the whole assembly rotates, generating a downward axial force to help high-viscosity materials overcome viscosity and flow downwards under gravity, preventing "wall-hanging" phenomena. The mounting rods 31 are hollow tubular structures. Inside each mounting rod 31, two shafts are placed in parallel: the push shaft 33 is closer to the inner side (towards the mounting shaft 3), and the rotating shaft 32 is closer to the outer side (towards the cylinder wall). The scraper 4 is directly fixed to the end of the rotating shaft 32 that extends out of the mounting rod 31.

[0035] The rotating shaft 32 and the pushing shaft 33 are not completely free inside the mounting rod 31; they are connected by an elastic element 34 (preferably a high-strength torsion spring or a compression spring connected by a baffle). Specifically, a first baffle 35 is fixed to the rotating shaft 32, and a second baffle 36 is fixed to the pushing shaft 33. The spring is compressed between the two baffles. When the pushing shaft 33 rotates relative to the rotating shaft 32, it changes the distance or angle between the two baffles, thereby changing the spring's compression or torsion angle, and consequently changing the preload applied by the spring to the rotating shaft 32 (i.e., changing the system's equivalent elastic coefficient).

[0036] A connecting component 8 is provided at the root position where the mounting shaft 3 connects to the mounting rod 31.

[0037] A preferred connecting component 8 is as follows: A vertical mounting groove 81 is formed in the hollow inner wall of the mounting shaft 3, and a rack 82 that can slide up and down is placed in the groove. A small gear 83 is fixed to the inner end of the push shaft 33, and the gear 83 passes through the root hole of the mounting rod 31 and meshes with the rack 82. To allow the rack 82 to move with the rise and fall of the drive shaft 5, an annular groove 84 is cut into the outer circumference of the drive shaft 5. A retaining block 85 extends from the back of the rack 82, and the end of the retaining block 85 is inserted into the annular groove 84. When the drive shaft 5 moves up and down due to the rotation of the servo motor, the annular groove 84 drives the retaining block 85 and the rack 82 to move up and down synchronously. The linear motion of the rack 82 drives the meshing gear 83 to rotate, and the gear 83 drives the push shaft 33 to rotate. The rotation of the push shaft 33 compresses or relaxes the internal spring.

[0038] In another embodiment, the connecting assembly 8 may also forgo the gear 83 and rack 82, instead employing a more robust push-pull structure. A sliding push bar 86 is disposed within a mounting groove 81 on the inner wall of the mounting shaft 3. A conical or beveled abutment block 87 is fixed to the drive shaft 5. The bottom of the push bar 86 also has a mating bevel. When the drive shaft 5 descends, the bevel of the abutment block 87 pushes the push bar 86 like a wedge, causing it to shift or rotate (in conjunction with a helical groove). Alternatively, the push bar 86 can be directly connected to the eccentric position of the drive shaft 33. This structure has a higher load-bearing capacity and is suitable for ultra-large equipment, although its adjustment precision is slightly inferior to that of the gear 83 and rack 82.

[0039] Adjusting the spring force alone is not enough; it is also necessary to control the movement trajectory of the scraper 4 when it retracts under force. This invention incorporates a guide assembly 9 between the rotating shaft 32 and the mounting rod 31.

[0040] The guide assembly 9 includes an arc-shaped guide groove 91 formed on the inner wall of the mounting rod 31, and an arc-shaped block 92 (or pin) fixed to the rotating shaft 32. The geometry of this arc-shaped guide groove 91 is precisely calculated. When the scraper 4 scrapes material on the cylinder wall, the material generates a reaction force (resistance) on the scraper 4. This resistance torque is transmitted to the rotating shaft 32. The rotating shaft 32 attempts to rotate to avoid this resistance. At this time, the arc-shaped block 92 slides within the arc-shaped guide groove 91. The trajectory of the guide groove forces the rotating shaft 32 to retract radially (move towards the center of the mounting shaft 3) while rotating. This means that the greater the resistance, the larger the rotation angle of the rotating shaft 32, the greater the radial retraction distance, and the larger the gap between the scraper 4 and the cylinder wall. This forms a perfect adaptive negative feedback mechanism: when encountering extremely high viscosity or hard lumps, the scraper 4 automatically yields a larger gap to avoid hard scraping that could cause motor overload or equipment damage; after the lumps pass, the scraper 4 resets under the action of the spring restoring force and continues film coating.

[0041] Working principle of the invention: When processing low-viscosity polymer solutions, the material has good flowability and easily flows down quickly under gravity. If left uncontrolled, the residence time on the cylinder wall is too short, resulting in insufficient volatilization. Assuming the servo motor rotates forward, the drive shaft 5 moves upward to a higher position. The rotation of drive shaft 5 drives the sealing ring 22, reducing the overlap between the feed hole 21 and the sealing hole 23. The smaller diameter of the feed hole 21 increases flow resistance, limiting the feed rate of the low-viscosity liquid. The drive shaft 5 rises, driving the rack 82 upward, and the drive gear 83 and the push shaft 33 rotate in opposite directions. At this time, the second baffle 36 retracts, the spring is in a relaxed state, and the preload is small. Because the low-viscosity fluid has very little resistance to the scraper 4, a large clamping force is not required. The softer spring allows the scraper 4 to gently conform to the liquid film, avoiding the scraping of the extremely thin liquid film. Due to the small spring force and low fluid resistance, the rotating shaft 32 is in the initial position in the guide groove, and the scraper 4 maintains a small basic gap (or even zero gap contact), ensuring the formation of an extremely thin turbulent liquid film on the cylinder wall, which greatly increases the specific surface area and enhances solvent evaporation. When processing high-viscosity polymer melts, the material flow is extremely slow, and the viscous resistance is enormous, easily leading to overheating and buildup on the cylinder wall. The servo motor is reversed, causing the drive shaft 5 to move downwards to a lower position. The rotation of drive shaft 5 drives the sealing ring 22, ensuring that the sealing hole 23 completely overlaps with the feed hole 21 (maximum overlap). This maximized flow area ensures that the high-viscosity melt can smoothly enter the cylinder 1 without clogging the distribution cavity. Drive shaft 5 descends, causing rack 82 to descend, and drive gear 83 and push shaft 33 to rotate forward. The second baffle 36 presses forward, greatly compressing the spring and storing enormous elastic potential energy. At this point, the scraper 4 system becomes "very stiff." This is necessary because high-viscosity materials generate enormous normal stress and shear resistance. If the spring is too soft, scraper 4 will be easily pushed aside by the material and fail, unable to perform its function of scraping and renewing the surface. The high rigidity ensures that scraper 4 can powerfully shear the material. Although the spring preload is increased, the high viscosity of the material also creates significant resistance. This enormous resistance torque acts on the rotating shaft 32, forcing it to overcome the strong spring force and rotate and retract along the arc-shaped guide groove 91. As a result, scraper 4 automatically creates a larger balance gap. This larger gap (e.g., 1-3 mm) is suitable for high-viscosity materials, ensuring that the material can pass through without jamming, while also achieving surface renewal through powerful shearing. At this point, the helical arrangement of the mounting rod 31 plays a crucial role. Under the high-speed rotation of the main shaft, scraper 4 generates a significant downward thrust, forcibly pushing the high-viscosity melt downwards like a screw pump, ensuring a narrow residence time distribution of the material and preventing localized overheating and degradation.

[0042] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A polymer volatile removal apparatus comprising: A cylinder (1), a material liquid distribution cavity (2) arranged on the top of the cylinder (1), a mounting shaft (3) arranged along the axial direction of the cylinder (1), and a scraper (4), characterized in that: A plurality of feeding holes (21) in communication with the inside of the cylinder (1) are uniformly arranged along the circumferential direction of the material liquid distribution cavity (2), a blocking ring (22) is arranged in rotation in the material liquid distribution cavity (2), a blocking hole (23) matched with the feeding hole (21) is formed in the blocking ring (22), the coincidence degree of the feeding hole (21) and the blocking hole (23) is adjusted by the rotation of the blocking ring (22), the mounting shaft (3) is hollow, a driving shaft (5) is coaxially arranged in the mounting shaft (3), the driving shaft (5) is threadedly connected with the mounting shaft (3); the cylinder (1) is provided with a driving member (6) for rotating the driving shaft (5); the driving shaft (5) is connected with the blocking ring (22) through a connecting mechanism (7), so that the driving shaft (5) drives the blocking ring (22) to rotate synchronously when the driving shaft (5) rotates; A mounting rod (31) is helically arranged on the outer periphery of the mounting shaft (3) and is hollow, a rotating shaft (32) and a pushing shaft (33) are coaxially arranged in the mounting rod (31); the scraper (4) is connected to one end of the rotating shaft (32) close to the inner wall of the cylinder (1); an elastic member (34) is arranged between the rotating shaft (32) and the pushing shaft (33), a connecting assembly (8) is arranged between the pushing shaft (33) and the driving shaft (5), when the driving shaft (5) axially ascends or descends, the pushing shaft (33) rotates relative to the mounting rod (31), so as to adjust the pre-tightening force of the elastic member (34), a guide assembly (9) is arranged between the rotating shaft (32) and the mounting rod (31), when the rotating shaft (32) rotates under force, the guide assembly (9) guides the rotating shaft (32) to produce radial displacement, so as to adjust the distance between the scraper (4) and the inner wall of the cylinder (1).

2. The polymer volatile matter removal apparatus of claim 1, wherein The driving member (6) is a servo motor, the driving shaft (5) is connected to the output end of the servo motor; an internal thread is formed in the inner wall of the mounting shaft (3), an external thread is formed in the outer surface of the driving shaft (5), the internal thread and the external thread are engaged with each other, so as to realize the axial linear motion of the driving shaft (5) while rotating; the servo motor can rotate in opposite directions, so as to control the ascending or descending direction of the driving shaft (5).

3. The polymer volatile matter removal apparatus of claim 1, wherein The connecting mechanism (7) comprises a connecting rod (71), a sliding groove (72) formed in the outer periphery of the driving shaft (5), and a sliding block (73) arranged in the sliding groove (72); the sliding groove (72) extends along the axial direction of the driving shaft (5), the sliding block (73) is slidingly arranged in the sliding groove (72); one end of the connecting rod (71) is hingedly connected to the blocking ring (22), and the other end is hingedly connected to the sliding block (73); when the driving shaft (5) rotates, the sliding groove (72) drives the sliding block (73) and the connecting rod (71) to rotate, and then drives the blocking ring (22) to rotate; when the driving shaft (5) ascends or descends, the sliding block (73) relatively slides in the sliding groove (72), so as to compensate the axial displacement.

4. The polymer devolatilization apparatus of claim 1, wherein The rotating shaft (32) is fixedly provided with a first baffle (35), the pushing shaft (33) is fixedly provided with a second baffle (36), and the elastic member (34) is a torsion compression spring or a cylindrical helical compression spring; one end of the elastic member (34) is connected to the first baffle (35), and the other end is connected to the second baffle (36); by changing the angle position of the pushing shaft (33) relative to the rotating shaft (32), the relative distance or angle between the first baffle (35) and the second baffle (36) can be changed, and then the elastic member (34) is compressed or relaxed.

5. The polymer volatile removal apparatus of claim 1, wherein The connecting assembly (8) comprises a mounting groove (81) formed in the inner wall of the mounting shaft (3), a rack (82) slidingly arranged in the mounting groove (81), a gear (83) fixedly arranged at the end of the pushing shaft (33), an annular clamping groove (84) formed in the outer periphery of the driving shaft (5), and a clamping block (85) fixedly arranged on one side of the rack (82); the gear (83) and the rack (82) are in meshing engagement; the end of the clamping block (85) extends into the annular clamping groove (84), so that the driving shaft (5) drives the rack (82) to move up and down when the driving shaft (5) is lifted or lowered, and then drives the gear (83) and the pushing shaft (33) to rotate, and the vertical position of the rack (82) is not affected when the driving shaft (5) rotates.

6. The polymer volatile removal apparatus of claim 1, wherein The connecting assembly (8) comprises a mounting groove (81) formed in the inner wall of the mounting shaft (3), a pushing bar (86) slidingly arranged in the mounting groove (81), an abutting block (87) fixedly arranged on the driving shaft (5), an annular clamping groove (84) formed in the outer periphery of the driving shaft (5), and a clamping block (85) fixedly arranged on one side of the pushing bar (86); the end of the pushing bar (86) is in contact with the end of the abutting block (87); the end of the clamping block (85) extends into the annular clamping groove (84), so that the driving shaft (5) drives the pushing bar (86) to move when the driving shaft (5) is lifted or lowered.

7. The polymer volatile removal apparatus of claim 1, wherein The guiding assembly (9) comprises an arc-shaped guiding groove (91) formed in the inner wall of the mounting rod (31) and an arc-shaped block (92) fixedly arranged on the rotating shaft (32); the arc-shaped block (92) is slidingly arranged in the arc-shaped guiding groove (91); when the rotating shaft (32) rotates in the direction of resistance of the scraper (4), the rotating shaft (32) is guided to retract away from the inner wall of the cylinder (1).

8. The polymer devolatilization apparatus of claim 1, wherein, The mounting rod (31) is distributed in a multi-head spiral line along the outer circumferential surface of the mounting shaft (3), and the spiral lift angle causes the scraper (4) to generate a downward axial thrust when scraping the polymer; the outer wall of the cylinder (1) is provided with a heating jacket or a heat tracing pipe for controlling the devolatilization temperature.

9. The polymer volatile removal apparatus of claim 1, wherein The bottom of the liquid distribution cavity (2) is funnel-shaped, and the feeding hole (21) is formed in the side wall of the funnel-shaped bottom; the plugging ring (22) is arranged on the inner wall of the liquid distribution cavity (2). The bottom of the liquid distribution cavity (2) is funnel-shaped, and the feeding hole (21) is formed in the side wall of the funnel-shaped bottom; the plugging ring (22) is arranged on the inner wall of the liquid distribution cavity (2).

10. The polymer volatile matter removal apparatus of any one of claims 1-9, wherein, The removing device further comprises a control unit electrically connected with the driving member (6) for controlling the rotating direction and the number of turns of the driving member (6) according to the viscosity parameter of the polymer to be treated, so as to synchronously adjust the feeding flow, the elastic coefficient of the elastic member (34) and the basic distance between the scraper (4) and the cylinder wall.

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