A kind of dynamic adjustable axial flow fan blade root sealing device

Abstract

The utility model relates to a dynamic adjustment axial flow fan sealing technical field discloses a kind of dynamic adjustment axial flow fan blade root sealing device, including air duct, motor, fan hub and the blade that is evenly distributed in the outer circumferential wall of fan hub, blade root is integrally connected with blade shaft;Fan hub outer wall is integrally formed with twelve groups of evenly distributed mounting seat, mounting seat is opened with the mounting hole for blade shaft to wear and tear along its own axis, and is equipped with installation hole;The end of blade shaft away from blade extends to the inside of fan hub and is transmission connection with the angle adjusting mechanism in fan hub, penetrating mounting hole;The cooperation gap of blade shaft and mounting seat is equipped with root sealing device. The present application is assisted by repulsion of magnetic pole of permanent magnet and abutting spring, drives first permanent magnet to extrude rubber ring to form high-efficiency radial seal, can actively fill dynamic gap to prevent leakage and prevent impurities from entering, and can self-adapting blade shaft adjustment displacement not increase resistance, also can maintain stable sealing force after slight wear of rubber ring.

Description

Technical Field

[0001] This utility model relates to the field of sealing technology for dynamically adjustable axial flow fans, specifically a sealing device for the root of the blades of a dynamically adjustable axial flow fan. Background Technology

[0002] Adjustable axial flow fans (i.e., axial flow fans with adjustable blades) are core ventilation and gas conveying equipment in industrial fields such as power, mining, petrochemical, and metallurgy. With the core advantage of real-time adjustment of blade angle, they can flexibly adapt to the dynamic requirements of air volume and air pressure under different operating conditions. They are widely used in key scenarios such as high-temperature flue gas conveying and harmful gas emission, effectively solving the pain point of low efficiency of fixed blade fans under changing operating conditions, and are an important guarantee for the stable operation of industrial systems.

[0003] Dynamically adjustable axial flow fans rely on the dynamic coordination between the blade root shaft and the adjustment mechanism within the hub. The blade shaft needs to rotate around its own axis to change the installation angle, inevitably resulting in a dynamic gap of 0.52mm to 2mm between it and the hub mounting hole. This gap can cause problems: firstly, high-pressure airflow or harmful / corrosive media can leak into the hub through the gap, causing a decrease in fan efficiency; secondly, dust, water vapor, and other impurities can intrude into the hub, wearing down and corroding the adjustment mechanism, leading to decreased blade adjustment accuracy or jamming, thus losing the advantages of dynamic adjustment.

[0004] Existing sealing solutions have drawbacks: when the fan flue gas temperature is low, condensation forms an acidic liquid, which corrodes the walls of the gaps, producing rust and scale. Simultaneously, the acidic liquid mixes with ash to form scale, which adheres to the gaps and inside the hub, leading to increased or uneven blade adjustment torque. This ultimately causes blade jamming, component damage, and forces the fan to shut down. Therefore, we propose a dynamically adjustable axial flow fan blade root sealing device to address the aforementioned problems. Utility Model Content

[0005] The purpose of this utility model is to provide a sealing device for the root of the blades of a dynamically adjustable axial flow fan, so as to solve the problems mentioned in the background art, such as the dynamic gap between the blade shaft and the hub mounting hole of the dynamically adjustable axial flow fan, which causes high-pressure airflow, leakage of harmful media, intrusion of impurities, scaling, blockage and corrosion of the gap, resulting in blade adjustment jamming, component damage and shutdown.

[0006] This utility model provides the following technical solution:

[0007] A dynamically adjustable axial flow fan blade root sealing device includes a fan casing, a motor, a fan hub, and blades evenly distributed on the outer circumferential wall of the fan hub. A blade shaft is integrally connected to the root of each blade. The outer wall of the fan hub is integrally formed with twelve evenly distributed mounting seats. Each mounting seat has a through-hole along its own axis for the blade shaft to pass through. The end of the blade shaft furthest from the blade extends through the mounting hole into the fan hub and is connected to an angle adjustment mechanism within the fan hub.

[0008] A root sealing device is provided at the fit gap between the blade shaft and the mounting base. A first mounting groove is provided on the top of the mounting base near the mounting hole. Bolt grooves are provided on the top of the mounting base near the outer walls on both sides.

[0009] Preferably, the root sealing device includes a sealing sleeve adapted to the top of the mounting base, a first permanent magnet, a second permanent magnet, an abutment spring, and a rubber ring; the sealing sleeve is fitted around the outer circumference of the blade shaft, and a second mounting groove is provided at its bottom; the rubber ring is fitted around the outside of the blade shaft and embedded in the top of the second mounting groove, and a sealing abutment groove is provided at the bottom of the rubber ring, and an abutment slope structure is provided on the inner wall of the sealing abutment groove near the blade shaft.

[0010] Preferably, the first permanent magnet is annular and sleeved on the outside of the blade shaft, and is embedded in the second mounting groove below the rubber ring; the top of the first permanent magnet is provided with a first protruding ring that is adapted to and abuts against the sealing abutting ring groove, and the inner wall of the top of the first protruding ring is provided with an abutting structure that slides and abuts against the abutting slope structure.

[0011] Preferably, the second permanent magnet is annular and embedded in the first mounting groove. The second permanent magnet and the first permanent magnet are arranged opposite each other and their magnetic poles repel each other. Embedding grooves are symmetrically provided on both sides of the top of the second permanent magnet. The abutting spring is vertically installed inside the embedding groove, and its top abuts against the bottom of the first permanent magnet.

[0012] Preferably, the second permanent magnet generates an upward repulsive force on the first permanent magnet, forcing the first permanent magnet to drive the first convex ring to squeeze and seal against the ring groove. At the same time, the abutment structure squeezes and abuts against the sliding structure, so that the inner wall of the rubber ring tightly fits the outer circumferential surface of the blade shaft, forming a radial seal.

[0013] Preferably, the top of both sides of the sealing sleeve is symmetrically provided with mounting screw holes, and a fixing bolt is inserted into the mounting screw hole. The bottom of the fixing bolt is threaded to the bolt groove to realize the fixed connection between the sealing sleeve and the mounting base.

[0014] This utility model has the following beneficial effects:

[0015] 1. This application utilizes the repulsive force between the magnetic poles of the second and first permanent magnets to drive the first permanent magnet to compress the sealing groove of the rubber ring with the first convex ring. Simultaneously, the abutment structure compresses the sliding structure, ensuring that the inner wall of the rubber ring tightly adheres to the outer circumferential surface of the blade shaft, forming a highly efficient radial seal. This structure can actively fill the dynamic gap between the blade shaft and the mounting base, effectively preventing leakage of high-pressure airflow, harmful, and corrosive media. It also isolates dust, water vapor, and other impurities from intruding into the wind turbine hub, avoiding wear and corrosion of the adjustment mechanism, and ensuring stable wind turbine efficiency and dynamic adjustment functions.

[0016] 2. The sealing sleeve and blade shaft are in non-rigid contact. The rubber ring has a certain degree of elasticity, and the magnetic repulsion combined with the contact spring can adapt to the slight displacement during blade shaft rotation adjustment, without increasing the resistance to blade angle adjustment. Compared with existing labyrinth seals, which are prone to jamming due to improper gaps and have high frictional resistance in packing seals, this device can ensure that the blades rotate smoothly around their own axis, maintain adjustment accuracy, and avoid affecting the fan's adaptability to changing operating conditions due to the sealing structure.

[0017] 3. The repulsive force between the second and first permanent magnets provides a long-lasting driving force. Combined with the auxiliary compensation effect of the retaining spring, it can continuously provide stable extrusion pressure even after the rubber ring has undergone slight wear over long-term use, preventing sealing failure due to weakening sealing force. Compared to the shortcomings of existing elastic sealing sheets that are prone to aging and require frequent packing, this device requires no frequent maintenance, reducing operating costs and extending the overall service life of the sealing device. Attached Figure Description

[0018] Figure 1 This is an isometric view of the dynamic axial flow fan of this utility model.

[0019] Figure 2 This is a schematic diagram of the wind turbine hub and blade structure of this utility model.

[0020] Figure 3 For the present utility model Figure 2 Enlarged view of area A in the middle.

[0021] Figure 4 This is a side view of the blade shaft of this utility model being installed with the wind turbine hub via a root sealing device.

[0022] Figure 5 This is a side view of the root sealing device of this utility model.

[0023] Figure 6 This is an enlarged side view of the rubber ring and the first permanent magnet of this utility model being installed and abutting.

[0024] In the diagram: 1. Air duct; 2. Motor; 3. Fan hub; 31. Mounting base; 311. First mounting groove; 312. Bolt groove; 32. Mounting hole; 4. Blade; 41. Blade shaft; 5. Root sealing device; 51. Sealing sleeve; 511. Second mounting groove; 512. Mounting screw hole; 52. First permanent magnet; 521. First convex ring; 523. Abutment structure; 53. Second permanent magnet; 531. Embedded groove; 54. Abutment spring; 55. Rubber ring; 551. Sealing abutment ring groove; 552. Abutment slope structure; 56. Fixing bolt. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see Figure 1 - Figure 3 As shown, a dynamically adjustable axial flow fan blade root sealing device includes a fan casing 1, a motor 2, a fan hub 3, and blades 4 evenly distributed on the outer circumferential wall of the fan hub 3. The motor 2 is installed inside the fan casing 1 via a T-shaped fixing seat, and the output end of the motor 2 is fixedly connected to the fan hub 3. The fan hub 3 is provided with an adjustment mechanism for adjusting the angle of the blades 4. A blade shaft 41, made of 45# steel, is integrally connected to the root of the blades 4 to ensure strength and transmission stability. Twelve sets of evenly distributed mounting seats 31 are integrally formed on the outer wall of the fan hub 3. The mounting seats 31 have mounting holes 32 through which the blade shafts 41 pass along their own axis. The end of the blade shaft 41 away from the blades 4 passes through the mounting holes 32 and extends... Extending into the interior of the fan hub 3, it is connected to the angle adjustment mechanism inside the fan hub 3 to realize blade angle adjustment. When the power supply mechanism starts the motor 2 to work, the motor 2 drives the fan hub 3 and the blades 4 on its outer wall to rotate to transport flue gas. When it is necessary to adjust the blades 4, the angle adjustment mechanism inside the fan hub 3 drives the blade shaft 41 connected to the bottom of the blades 4 to rotate to adjust the angle. The top of the mounting base 31 near the mounting hole 32 is provided with a first mounting groove 311 for embedding the second permanent magnet 53 for root sealing. The top of the mounting base 31 near the outer walls on both sides is provided with bolt grooves 312, through which the root sealing device 5 is connected to the mounting base 31.

[0027] Please see Figure 2 - Figure 6As shown, a root sealing device 5 is provided at the mating gap between the blade shaft 41 and the mounting base 31. The root sealing device 5 includes a sealing sleeve 51 adapted to the top of the mounting base 31, a first permanent magnet 52, a second permanent magnet 53, a retaining spring 54, and a rubber ring 55. The sealing sleeve 51 is fitted around the outer circumference of the blade shaft 41 and is made of 304 stainless steel, which is resistant to atmospheric corrosion and suitable for most industrial environments. A second mounting groove 511 is provided at its bottom to accommodate the rubber ring 55 and the first permanent magnet 52. Mounting screw holes 512 are symmetrically provided through the top of both sides of the sealing sleeve 51. A fixing bolt 56 is provided to allow for the detachable fixing of the sealing sleeve 51 and the mounting base 31, facilitating maintenance and replacement. The rubber ring 55 is sleeved on the outside of the blade shaft 41 and embedded in the top of the second mounting groove 511. The rubber ring 55 is made of fluororubber (temperature resistance -20℃ to 200℃, strong acid and alkali resistance, and oil resistance, suitable for acidic environments where flue gas condensation occurs). A sealing abutment ring groove 551 is provided at the bottom of the rubber ring 55. The inner wall of the sealing abutment ring groove 551 near the blade shaft 41 is provided with an abutment sliding structure 552. The inclined design facilitates deformation towards the blade shaft 41 when compressed, ensuring sealing performance. The first permanent magnet 52 is annular and sleeved on the outside of the blade shaft 41, and is embedded in the second mounting groove 511 below the rubber ring 55. It is made of neodymium iron boron permanent magnet (grade N35, strong magnetic force, high coercivity, and low magnetic force attenuation rate after long-term use). The top of the first permanent magnet 52 is provided with a first protruding ring 521 that fits and abuts against the sealing abutting ring groove 551. The inner wall of the top of the first protruding ring 521 is provided with an abutting structure 523 that slides and abuts against the abutting slope structure 552. The inclined surface that matches the abutting slope structure 552 is used to squeeze the rubber ring 55 to generate deformation, prevent leakage between the sealing sleeve 51 and the outer circumference of the blade shaft 41, and ensure sealing.

[0028] The second permanent magnet 53 is annular and embedded in the first mounting groove 311. The second permanent magnet 53 is a neodymium iron boron permanent magnet (N35). The second permanent magnet 53 and the first permanent magnet 52 are arranged vertically opposite each other and their magnetic poles repel each other (like magnetic poles repel each other, generating a continuous upward repulsive force). The top of the second permanent magnet 53 has symmetrically arranged embedding grooves 531 on both sides. The abutment spring 54 is vertically installed inside the embedding groove 531, and its top abuts against the bottom of the first permanent magnet 52. The abutment spring 54 is made of austenitic stainless steel, which has high tensile strength, long fatigue life, and is suitable for long-term reciprocating motion. Compensation requirements; the second permanent magnet 53 generates an upward repulsive force on the first permanent magnet 52, forcing the first permanent magnet 52 to drive the first convex ring 521 to squeeze and seal the sealing abutment ring groove 551. At the same time, the abutment structure 523 of the first convex ring 521 slides and squeezes along the abutment slope structure 552 of the rubber ring 55, causing the inner wall of the rubber ring 55 to deform towards the blade shaft 41, tightly fitting the outer circumferential surface of the blade shaft 41, forming a reliable radial seal; the abutment spring 54 moves and compresses with the first permanent magnet 52, generating an upward auxiliary elastic force to ensure that the sealing force does not decrease during long-term use.

[0029] Workflow: The blade shaft 41 at the base of the blade passes through the sealing sleeve 51 and extends below it. A rubber ring 55 is fitted onto the blade shaft 41 and inserted into the top of the second mounting groove 511 at the bottom of the sealing sleeve 51. Then, the first permanent magnet 52 is fitted onto the blade shaft 41 and placed in the second mounting groove 511 below the rubber ring 55, ensuring that the first protruding ring 521 at the top of the first permanent magnet 52 is aligned with the sealing abutment groove 551 of the rubber ring 55. The second permanent magnet 53 is embedded into the first mounting groove 311 at the top of the mounting base 31, ensuring its centered position and forming an upper-lower relative structure with the subsequent first permanent magnet 52. The abutment spring 54 is vertically placed into the embedding grooves 531 on both sides of the top of the second permanent magnet 53, ensuring that the top of the spring is flush and has uniform elasticity compensation capability. The blade... The bottom of the blade shaft 41 is aligned with the mounting hole 32 of the mounting seat 31 on the outer wall of the fan hub 3, and is inserted into the inside of the fan hub 3. At this time, the sealing sleeve 51 is fastened to the top of the mounting seat 31, so that the mounting screw holes 512 on both sides of the sealing sleeve 51 are aligned with the bolt grooves 312 of the mounting seat 31. The fixing bolts 56 are inserted and tightened to complete the detachable fixing of the sealing sleeve 51 and the mounting seat 31. At this time, the bottom of the first permanent magnet 52 naturally abuts against the top of the abutment spring 54 to form an initial sealing state. The power supply mechanism starts the motor 2, and the motor 2 drives the fan hub 3 and the blades 4 on the outer wall to rotate at high speed. The external flue gas flows along the axial direction of the wind tunnel 1 under the action of the blades 4 to realize the flue gas transportation. During this process, at the gap between the blade shaft 41 and the mounting seat 31, the root sealing device 5 automatically enters the sealing working state. The second permanent magnet 53 and the first permanent magnet 52, being opposite each other and with their magnetic poles repelling each other, generate a continuous upward repulsive force. This repulsive force forces the first permanent magnet 52 to move upward within the second mounting groove 511 of the sealing sleeve 51, causing the first convex ring 521 at the top to press against the sealing abutment groove 551 of the rubber ring 55. While the first convex ring 521 presses against the sealing abutment groove 551, the abutment structure 523 on its top inner wall slides and presses along the abutment slope structure 552 of the rubber ring 55. Utilizing the guiding effect of the inclined surface, the inner wall of the rubber ring 55 is forced to deform towards the blade shaft 41, ultimately tightly fitting against the outer circumference of the blade shaft 41, forming a reliable radial seal. This prevents high-pressure flue gas, dust, and water vapor from leaking or intruding into the wind turbine hub 3 through the gap between the blade shaft 41 and the mounting base 31. During the upward movement of the first permanent magnet 52, the abutment spring 54 is compressed and generates an upward auxiliary elastic force, which works in conjunction with the magnetic repulsion force to ensure that the extrusion force of the first permanent magnet 52 on the rubber ring 55 is stable. Even if the rubber ring 55 experiences slight wear during long-term operation, the elastic force of the abutment spring 54 can compensate for the displacement, and together with the magnetic repulsion force, maintain the sealing force without attenuation, ensuring a long-lasting and reliable sealing effect.

[0030] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0031] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A dynamically adjustable axial flow fan blade root sealing device, comprising a fan casing (1), a motor (2), a fan hub (3), and blades (4) uniformly distributed on the outer circumferential wall of the fan hub (3), characterized in that: The blade (4) is integrally connected to the root of the blade shaft (41); the outer wall of the wind turbine hub (3) is integrally formed with twelve sets of evenly distributed mounting seats (31), and the mounting seats (31) are provided with mounting holes (32) through their own axis for the blade shaft (41) to pass through; the end of the blade shaft (41) away from the blade (4) extends through the mounting hole (32) into the inside of the wind turbine hub (3) and is connected to the angle adjustment mechanism inside the wind turbine hub (3) for transmission. A root sealing device (5) is provided at the fitting gap between the blade shaft (41) and the mounting base (31). A first mounting groove (311) is provided on the top of the mounting base (31) near the mounting hole (32). Bolt grooves (312) are provided on the top of the mounting base (31) near the outer walls on both sides.

2. The blade root sealing device for a dynamically adjustable axial flow fan according to claim 1, characterized in that: The root sealing device (5) includes a sealing sleeve (51) adapted to the top of the mounting base (31), a first permanent magnet (52), a second permanent magnet (53), an abutment spring (54), and a rubber ring (55); the sealing sleeve (51) is fitted on the outer circumference of the blade shaft (41), and a second mounting groove (511) is provided at its bottom; the rubber ring (55) is fitted on the outside of the blade shaft (41) and embedded in the top of the second mounting groove (511), and a sealing abutment ring groove (551) is provided at the bottom of the rubber ring (55), and an abutment sliding structure (552) is provided on the inner wall of the sealing abutment ring groove (551) near the blade shaft (41).

3. The blade root sealing device for a dynamically adjustable axial flow fan according to claim 2, characterized in that: The first permanent magnet (52) is annular and sleeved on the outside of the blade shaft (41), and is embedded in the second mounting groove (511) below the rubber ring (55); the top of the first permanent magnet (52) is provided with a first protruding ring (521) that is adapted to and abuts against the sealing abutting ring groove (551), and the inner wall of the top of the first protruding ring (521) is provided with an abutting structure (523) that slides and abuts against the abutting slope structure (552).

4. The blade root sealing device for a dynamically adjustable axial flow fan according to claim 3, characterized in that: The second permanent magnet (53) is ring-shaped and embedded in the first mounting groove (311). The second permanent magnet (53) and the first permanent magnet (52) are arranged opposite each other and their magnetic poles repel each other. The top two sides of the second permanent magnet (53) are symmetrically provided with embedding grooves (531). The abutting spring (54) is vertically installed inside the embedding groove (531), and its top abuts against the bottom of the first permanent magnet (52).

5. The blade root sealing device for a dynamically adjustable axial flow fan according to claim 4, characterized in that: The second permanent magnet (53) generates an upward repulsive force on the first permanent magnet (52), forcing the first permanent magnet (52) to drive the first convex ring (521) to squeeze and seal the sealing groove (551). At the same time, the abutting structure (523) squeezes and abuts the sliding structure (552), so that the inner wall of the rubber ring (55) is tightly attached to the outer circumferential surface of the blade shaft (41) to form a radial seal.

6. The blade root sealing device for a dynamically adjustable axial flow fan according to claim 2, characterized in that: The sealing sleeve (51) has symmetrical through-holes (512) on both sides of the top. A fixing bolt (56) is inserted in the mounting bolt hole (512). The bottom of the fixing bolt (56) is threaded into the bolt groove (312) to achieve a fixed connection between the sealing sleeve (51) and the mounting base (31).

Images