Rotary mechanism axial seal device and method, powder flattening apparatus

Abstract

The application provides a rotary mechanism axial sealing device and method and a powder flattening device. The rotary mechanism axial sealing device is used for sealing the axial direction of a rotary shaft and comprises a first sealing unit, a second sealing unit and a third sealing unit. The first sealing unit comprises a rotary sealing ring with a slope and a gland. The rotary sealing ring is sleeved on the rotary shaft, and the slope is tightly combined with the end surface of the gland under the axial pressure of the rotary shaft. The second sealing unit comprises a rotary pressure shaft seal, a spring pressing mechanism and a sealing shell. The sealing shell is sleeved on the rotary shaft, the rotary pressure shaft seal is arranged in the sealing shell, the inner diameter of the rotary pressure shaft seal is in interference fit with the rotary shaft, and the outer diameter of the rotary pressure shaft seal is in interference fit with the sealing shell. The spring pressing mechanism applies a continuous axial pressure to the rotary pressure shaft seal, so that the inner diameter of the rotary pressure shaft seal is kept in close contact with the rotary shaft. The third sealing unit comprises a radial lip-shaped sealing ring and a sealing shell. The radial lip-shaped sealing ring is arranged in the sealing shell, the inner diameter of the radial lip-shaped sealing ring is in interference fit with the rotary shaft, and the outer diameter of the radial lip-shaped sealing ring is in interference fit with the sealing shell.

Description

Technical Field

[0001] This invention relates to the field of mechanical seal technology, specifically to an axial sealing device and method for sealing the axial direction of a rotating shaft, and a powder flattening device. Background Technology

[0002] In powder processing equipment, such as soft magnetic alloy powder flattening equipment, axial sealing of its drive shaft (rotation shaft) is one of the key technologies. The working chamber of such equipment usually contains a mixture of powder and solvent, and it is necessary to prevent leakage along the rotation axis towards the drive mechanism (such as a motor). Otherwise, it will damage the motor and affect product quality (for example, affecting the flattening effect of metal powder, resulting in reduced electromagnetic shielding and wave absorption performance of the final device, as well as reduced flattened powder production).

[0003] Currently, mechanical seals are the most common sealing method. Mechanical seals achieve sealing through the relative sliding of the rotating and stationary rings; their structure is reliable and requires no adjustment during operation. However, mechanical seals have the following drawbacks: First, their structure is complex, requiring extremely stringent machining precision for the surface roughness and straightness of each component (such as the rotating and stationary rings); second, precise alignment of components is required during assembly to ensure that parameters such as spring compression and end face parallelism meet standards, making assembly difficult and costly; third, some existing equipment explicitly requires that the normal operating speed should not be too low (e.g., not less than 2500 rpm / min), otherwise the sealing effect will significantly decrease under low-speed conditions, and may even lead to seal failure, which limits the operating speed range and application scenarios of the equipment.

[0004] Therefore, there is an urgent need for an axial sealing solution that has a relatively simple structure, low requirements for machining and assembly precision, and can maintain a good sealing effect over a wider range of speeds (including low speeds).

[0005] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] This invention provides an axial sealing device and method for a rotating mechanism, as well as a powder flattening device. It has a simple structure, is easy to assemble, and can achieve effective axial sealing within a wide speed range (including low and high speeds) to prevent the medium in the working chamber from leaking along the rotating shaft.

[0007] The present invention adopts the following technical solution:

[0008] In a first aspect, an axial sealing device for a rotating mechanism is provided for sealing the axial direction of a rotating shaft to prevent leakage of medium in the working chamber along the rotating shaft toward the drive mechanism that drives the rotating shaft. The device includes: a first-stage sealing unit disposed near the working chamber, comprising a rotating sealing ring with an inclined surface and a pressure cap; the rotating sealing ring with the inclined surface is fitted onto the rotating shaft, and its inclined surface is tightly fitted with the end face of the pressure cap under the axial pressure of the rotating shaft to form an end face seal; and a second-stage sealing unit disposed near the drive mechanism, comprising a rotating pressure shaft seal, a spring clamping mechanism, and a sealing housing. The housing is fitted onto the rotating shaft. The rotary pressure shaft seal and the spring clamping mechanism are both disposed within the sealing housing. The inner diameter of the rotary pressure shaft seal 9 is interference-fitted with the rotating shaft, and its outer diameter is interference-fitted with the sealing housing. The spring clamping mechanism applies continuous axial pressure to the rotary pressure shaft seal to ensure that its inner diameter remains in close contact with the rotating shaft. The third-stage sealing unit includes a radial lip seal ring and the sealing housing. The radial lip seal ring is disposed within the sealing housing and is closer to the drive mechanism than the rotary pressure shaft seal. Its inner diameter is interference-fitted with the rotating shaft, and its outer diameter is interference-fitted with the sealing housing.

[0009] Secondly, a method for axial sealing of a rotating mechanism is provided, employing the axial sealing device for a rotating mechanism as described in the first aspect, comprising the following steps: 1) achieving a first-level seal by the tight fit between the rotating sealing ring with the inclined surface and the gland, thereby isolating the medium in the working chamber during low-speed operation of the equipment; 2) applying axial pressure to the rotating pressure shaft seal by the spring clamping mechanism, ensuring that the inner diameter of the rotating pressure shaft seal remains tightly fitted with the rotating shaft, thereby achieving a second-level seal to compensate for wear and prevent seal failure due to pressure fluctuations or centrifugal force during high-speed operation of the equipment; 3) achieving a third-level seal as final protection by the tight fit between the inner diameter of the radial lip sealing ring and the rotating shaft.

[0010] Thirdly, a powder flattening device is provided, comprising the axial sealing device of the rotating mechanism described in the first aspect.

[0011] This invention can operate stably and reliably over a wide speed range, and is easy to manufacture and maintain. Specifically, this invention has the following beneficial effects:

[0012] 1. This invention forms a multi-stage synergistic sealing barrier by setting up a first-stage sealing unit consisting of a rotating sealing ring with an inclined surface, a second-stage sealing unit consisting of a rotating pressure shaft seal clamped by a spring clamping mechanism, and a third-stage sealing unit consisting of a radial lip sealing ring. The first-stage sealing unit effectively handles low-speed conditions using end-face sealing; the second-stage sealing unit provides a continuous radial force adaptable to the rotational speed of the rotating shaft through the spring clamping mechanism, ensuring effective contact sealing even under high-speed, pressure fluctuation, and wear conditions; the third-stage sealing unit serves as the final safety guarantee. The three-stage sealing units work together to enable the sealing device as a whole to achieve reliable sealing across a wide speed range (e.g., 1500 to 4500 rpm) from low to high speeds, effectively overcoming the problems of poor performance of existing mechanical seals at low speeds and easy failure due to wear or pressure fluctuations at high speeds. This significantly expands the operating speed range of applicable equipment and improves sealing reliability.

[0013] 2. By adopting standard or mature sealing elements such as beveled rotary seals, rotary pressure shaft seals, and radial lip seals, and optimizing their layout, the overall structure is greatly simplified compared to complex mechanical seals. This not only reduces the extremely demanding machining precision requirements for individual parts (such as ultra-high surface finish and flatness), but also significantly reduces the technical requirements for precise alignment and parallelism adjustment during assembly, making the assembly process simpler and maintenance and replacement more convenient, thereby reducing manufacturing and maintenance costs. Attached Figure Description

[0014] Figure 1 This is an exploded view of the axial sealing device of the rotating mechanism in an embodiment of the present invention.

[0015] Figure 2 This is a three-dimensional structural diagram of the axial sealing device of the rotating mechanism in an embodiment of the present invention.

[0016] Figure 3 This is a three-dimensional structural diagram of the axial sealing device of the rotating mechanism in an embodiment of the present invention from another perspective.

[0017] Figure 4 This is a schematic diagram of the axial cross-sectional structure of the axial sealing device of the rotating mechanism in an embodiment of the present invention.

[0018] Figure 5 This is a cross-sectional schematic diagram of the rotary pressure shaft seal in an embodiment of the present invention.

[0019] In the diagram: 1. Rotary shaft; 2. Rotary sealing ring with bevel; 3. Spring base; 4. Compression spring; 5. Spring pressure seat; 6. Cooling chamber sealing cover; 7. Pressure cover; 8. Sealing housing; 81. Sealed cooling chamber; 811. Cooling medium inlet; 812. Cooling medium outlet; 9. Rotary pressure shaft seal; 91. V-groove; 10. Radial lip seal. Detailed Implementation

[0020] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0021] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0022] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] like Figure 1-5 As shown, a specific embodiment of the present invention provides an axial sealing device for a rotating mechanism, used to seal the axial direction of a rotating shaft 1 to prevent the medium in the working chamber from leaking along the rotating shaft 1 towards the driving mechanism that drives the rotating shaft to rotate. The axial sealing device for the rotating mechanism includes:

[0025] The first-stage sealing unit is located on the side near the working chamber and includes a rotating sealing ring 2 with an inclined surface and a pressure cap 7. The rotating sealing ring 2 with an inclined surface is fitted onto the rotating shaft 1, and its inclined surface is tightly fitted with the end face of the pressure cap 7 under the axial pressure of the rotating shaft 1 to form an end face seal.

[0026] The second-stage sealing unit, located near the drive mechanism, includes a rotary pressure shaft seal 9, a spring clamping mechanism, and a sealing housing 8. The sealing housing 8 is fitted onto the rotary shaft 1. Both the rotary pressure shaft seal 9 and the spring clamping mechanism are housed within the sealing housing 8. The inner diameter of the rotary pressure shaft seal 9 is interference-fitted with the rotary shaft 1, and its outer diameter is interference-fitted with the sealing housing 8. The spring clamping mechanism applies continuous axial pressure to the rotary pressure shaft seal 9 to ensure that the radial force it generates keeps its inner diameter in close contact with the rotary shaft 1 and compensates for wear.

[0027] The third-stage sealing unit includes a radial lip seal 10 and the sealing housing 8; the radial lip seal 10 is disposed inside the sealing housing 8 and is closer to the drive mechanism than the rotary pressure shaft seal 9, and its inner diameter is interference-fitted with the rotary shaft 1 and its outer diameter is interference-fitted with the sealing housing 8.

[0028] In some embodiments, the spring clamping mechanism includes a spring base 3, a compression spring 4, and a spring pressure seat 5. The pressure cover 7 is fixed inside the sealing housing 8, and the spring base 3 is fixed on the pressure cover 7. One end of the compression spring 4 is connected to the spring base 3, and the other end applies axial pressure to the rotating pressure shaft seal 9 through the spring pressure seat 5, so that the inner diameter of the rotating pressure shaft seal 9 is always in close contact with the rotating shaft 1.

[0029] In some embodiments, the axial pressure provided by the compression spring 4 is configured such that the radial force between the rotating pressure shaft seal 9 and the rotating shaft 1 is in the range of 1 N / cm to 2 N / cm.

[0030] In some embodiments, the axial pressure provided by the compression spring 4 is in the range of 18-25 N.

[0031] In some embodiments, the axial pressure provided by the compression spring 4 is configured such that when the linear velocity of the rotating shaft 1 is ≤4 m / s, the radial force between the rotating pressure shaft seal 9 and the rotating shaft 1 is in the range of 1.5 N / cm to 2 N / cm; and when the linear velocity of the rotating shaft 1 is >4 m / s, the radial force between the rotating pressure shaft seal 9 and the rotating shaft 1 is in the range of 1 N / cm to 1.5 N / cm.

[0032] By configuring the spring clamping mechanism to provide radial force correlated with the rotational axis speed, the contact state between the sealing lip of the rotary pressure shaft seal and the rotating shaft can be dynamically optimized. Providing a larger radial force at low speeds to ensure sealing performance, and appropriately reducing the radial force at high speeds to decrease frictional heat and wear, this characteristic allows the second-stage sealing unit to adapt to different operating conditions within the speed range of 1500 to 4500 rpm. While ensuring sealing performance, it extends the service life of the seals and improves the efficiency and economy of the entire sealing device under different operating conditions.

[0033] In some embodiments, the spring base 3 and the spring pressure seat 5 are both annular and are sleeved on the rotating shaft 1, and a plurality of compression springs 4 are evenly distributed between the spring base 3 and the spring pressure seat 5.

[0034] In some embodiments, the sealed housing 8 includes a sealed cooling cavity 81 and a cooling cavity sealing cover 6. The cooling cavity sealing cover 6 is connected to the sealed cooling cavity 81 to seal the cooling medium inside the sealed cooling cavity 81. The sealed cooling cavity 81 is provided with a cooling medium inlet 811 and a cooling medium outlet 812.

[0035] By incorporating a sealing housing with a cooling chamber, a circulating cooling medium (such as water) can remove the heat generated by the friction between the seals (such as the rotary pressure shaft seal 9 and the radial lip seal 10) and the rotating shaft. This effectively controls the temperature of the sealing area, preventing the seals from aging and failing due to overheating, and further ensuring the long-term stability of the sealing effect and the durability of the sealing elements.

[0036] In some embodiments, the rotary sealing ring 2 with bevels is made of fluororubber; the rotary pressure shaft seal 9 is made of polytetrafluoroethylene and carbon fiber composite material; and the radial lip seal 10 is made of fluororubber.

[0037] By selecting specific material combinations (such as fluororubber rotary seals with bevels and radial lip seals which have good media resistance and elasticity, and PTFE rotary pressure shaft seals with carbon fiber which have low friction coefficient and wear resistance), the corrosion resistance and operating condition adaptability of each sealing unit to specific media (such as powder solvents) are enhanced, thereby synergistically improving the overall performance of the entire device.

[0038] In some embodiments, the rotary seal 2 with an inclined surface is a V-shaped rotary seal; the radial lip seal 10 is a skeleton oil seal; the rotary pressure shaft seal 9 has a V-shaped groove 91, which is installed facing the working chamber and the V-shaped surface contacts the spring clamping mechanism.

[0039] A specific embodiment of the present invention also includes an axial sealing method for a rotating mechanism, employing the aforementioned axial sealing device for the rotating mechanism, comprising the following steps:

[0040] 1) The first-level seal is achieved by the tight fit between the inclined rotary sealing ring 2 and the pressure cap 7, so as to isolate the medium in the working chamber when the equipment is running at low speed;

[0041] 2) The spring clamping mechanism applies axial pressure to the rotary pressure shaft seal 9, so that the inner diameter of the rotary pressure shaft seal 9 always keeps in close contact with the rotary shaft 1, thereby achieving a second-level seal to compensate for wear and prevent seal failure caused by pressure fluctuations or centrifugal force when the equipment is running at high speed.

[0042] 3) The inner diameter of the radial lip seal 10 is tightly fitted with the rotating shaft 1 to achieve a third-level seal, serving as the final protection.

[0043] In some embodiments, in step 2), the axial pressure provided by the spring clamping mechanism makes the radial force between the rotating pressure shaft seal (9) and the rotating shaft (1) in the range of 1N / cm-2N / cm.

[0044] In some embodiments, in step 2), when the linear velocity of the rotating shaft (1) is ≤4m / s, the radial force is in the range of 1.5N / cm-2N / cm; when the linear velocity of the rotating shaft (1) is >4m / s, the radial force is in the range of 1N / cm-1.5N / cm.

[0045] A specific embodiment of the present invention also includes a powder flattening device, which includes the aforementioned rotating mechanism axial sealing device.

[0046] Applying the axial sealing device of the rotating mechanism of the present invention to a powder flattening equipment can effectively prevent solvents, such as alcohol, from leaking into the motor. This protects the motor, ensures the stability of the powder flattening process and product quality, and improves production safety and powder recovery rate.

[0047] The following describes specific embodiments of the present invention.

[0048] like Figure 1-5As shown, in this example, the axial sealing device of the rotating mechanism is used in the powder flattening equipment. The axial sealing device of the rotating mechanism is sleeved on the rotating shaft of the powder flattening equipment to seal the axial direction of the rotating shaft 1. The axial sealing device of the rotating mechanism is set between the working chamber of the powder flattening equipment (for containing powder and solvent) and the drive mechanism (such as a drive motor) that drives the rotating shaft 1 to rotate, so as to prevent the solvent from leaking towards the drive mechanism. The axial sealing device of the rotating mechanism includes a first-stage sealing unit, a second-stage sealing unit and a third-stage sealing unit arranged sequentially from the side near the working chamber to the side near the drive mechanism.

[0049] The first-stage sealing unit includes a beveled rotary sealing ring 2 (in this example, a V-shaped rotary sealing ring) and a pressure cap 7. The pressure cap 7 is located below the beveled rotary sealing ring 2. The beveled rotary sealing ring 2 is fitted onto the rotary shaft 1. One side of the beveled rotary sealing ring 2 is flat (serving as a mounting surface, in close contact with the stepped surface of the rotary shaft 1), and the other side is beveled (serving as a sealing surface, in close contact with the pressure cap 7). Under the axial pressure applied by the rotary shaft 1 to the beveled rotary sealing ring 2, this beveled surface tightly fits against the end face of the pressure cap 7, forming an end face seal. At the same time, the centrifugal force generated by rotation enhances the sealing effect. Specifically, when the rotary shaft 1 is connected to the output shaft of the drive mechanism, the distance between the stepped surface on the rotary shaft 1 and the pressure cap 7 is less than the distance between the two end faces of the rotary sealing ring 2. Therefore, after assembly, the rotary shaft 1 will apply an axial force to the rotary sealing ring 2, causing its other end face (beveled surface) to fit tightly against the pressure cap 7.

[0050] The second-stage sealing unit includes a rotary pressure shaft seal 9, a spring clamping mechanism, and a sealing housing 8. The sealing housing 8 is fitted onto the rotary shaft 1. Both the rotary pressure shaft seal 9 and the spring clamping mechanism are located within the sealing housing 8. The rotary pressure shaft seal 9 is fitted onto the rotary shaft 1 with its inner diameter and outer diameter both interfering with the sealing housing 8 (i.e., the outer diameter of the rotary pressure shaft seal 9 is tightly fitted to the wall of the central through hole of the sealing housing 8). The V-groove 91 of the rotary pressure shaft seal 9 is installed facing the working chamber side, and the V-shaped surface contacts the spring clamping mechanism. The spring clamping mechanism applies continuous axial pressure to the rotary pressure shaft seal 9 to ensure that the radial force generated by the rotary pressure shaft seal 9 keeps its inner diameter in close contact with the rotary shaft 1. At the same time, it compensates for the wear of the rotary pressure shaft seal, so that even when the rotary pressure shaft seal 9 is worn, its inner side can still fit tightly with the rotary shaft 1, ensuring a sealing effect. The spring clamping mechanism includes a spring base 3, a compression spring 4, and a spring pressure seat 5. Both the spring base 3 and the spring pressure seat 5 are annular and are fitted onto the rotating shaft 1. The spring base 3 has several mounting holes. A plurality of evenly distributed compression springs 4 (in this example, six springs are evenly distributed and installed in the mounting holes on the spring base 3) are provided between the spring base 3 and the spring pressure seat 5. The spring base 3 is fixed to the pressure cover 7 by screws. The pressure cover 7 is fixed to the sealing housing 8 by bolts and is located between the sealing housing 8 and the inclined rotating sealing ring. One end of the compression spring 4... The spring is fixedly connected to the spring base 3, and the other end applies axial pressure to the rotating pressure shaft seal 9 through the spring pressure seat 5, so that the inner diameter of the rotating pressure shaft seal 9 is always in close contact with the rotating shaft 1. That is, the spring pressure seat 5, which is located between the compression spring 4 and the rotating pressure shaft seal 9, contacts the V-shaped surface of the V-shaped groove 91 of the rotating pressure shaft seal 9, and transmits the axial pressure generated by the compression spring 4 to the rotating pressure shaft seal 9, thereby causing the rotating pressure shaft seal 9 to generate a radial force, increasing the friction between it and the rotating shaft 1, and thus ensuring that the inner diameter of the rotating pressure shaft seal 9 is always in close contact with the rotating shaft 1.

[0051] The third-stage sealing unit includes a radial lip seal 10 (in this example, a skeleton oil seal) and the sealing housing 8. The radial lip seal 10 is disposed inside the sealing housing 8 and fitted onto the rotating shaft 1. The radial lip seal 10 is closer to the drive mechanism than the rotating pressure shaft seal 9. The inner diameter of the radial lip seal 10 is interference-fitted with the rotating shaft 1, and the outer diameter is interference-fitted with the sealing housing 8 (i.e., the outer diameter of the radial lip seal 10 is tightly fitted with the wall of the central through hole of the sealing housing 8).

[0052] In this example, the sealing housing 8 includes a sealing cooling chamber 81 and a cooling chamber sealing cover 6. The cooling chamber sealing cover 6 is connected to the sealing cooling chamber 81 to seal the cooling medium inside the sealing cooling chamber 81. The sealing cooling chamber 81 is provided with a cooling medium inlet 811 and a cooling medium outlet 812. During the operation of the powder flattening equipment, a cooling medium (in this example, water) is continuously introduced into the sealing cooling chamber to remove the heat generated by the friction between the seal and the rotating shaft 1.

[0053] In this example, the axial pressure provided by the compression spring 4 is in the range of 18-25N. The axial pressure provided by the compression spring 4 satisfies the following conditions: when the linear velocity of the rotating shaft 1 is ≤4m / s, the radial force between the rotating pressure shaft seal 9 and the rotating shaft 1 is in the range of 1.5N / cm-2N / cm; when the linear velocity of the rotating shaft 1 is >4m / s, the radial force between the rotating pressure shaft seal 9 and the rotating shaft 1 is in the range of 1N / cm-1.5N / cm. In practical applications, the compression spring 4 can be selected according to the range of linear velocity of the rotating shaft 1 to ensure that the axial pressure it provides is compatible with the corresponding linear velocity.

[0054] In this example, the rotary sealing ring 2 with its bevel and the radial lip sealing ring 10 are both made of fluororubber; the rotary pressure shaft seal 9 is made of polytetrafluoroethylene and carbon fiber composite material.

[0055] During assembly, first, the beveled rotary sealing ring 2 is fitted onto the rotating shaft 1. Then, the pressure cap 7, the spring clamping mechanism, and the rotary pressure shaft seal 9 are sequentially installed onto the rotating shaft 1. The entire assembly is then installed from above the sealing housing 8 at the center hole of the sealing housing 8. Next, the radial lip seal 10 is installed from below the sealing housing 8 (from the working chamber to the drive mechanism, the pressure cap 7, spring clamping mechanism, rotary pressure shaft seal 9, and radial lip seal 10 are sequentially located within the central through hole of the sealing housing (specifically, the sealing cooling chamber 81); the beveled rotary sealing ring 2 is located outside the sealing cooling chamber 81, between the pressure cap 7 and the stepped surface of the rotating shaft 1). Finally, the cooling chamber sealing cover plate 6 is installed below the radial lip seal 10. Using the above-described axial sealing device for the rotating mechanism, the axial sealing method for the rotating mechanism includes the following process:

[0056] 1) The first-level seal is achieved by the tight fit between the inclined rotary sealing ring 2 and the pressure cap 7, so as to isolate the medium in the working chamber when the equipment is running at low speed;

[0057] 2) The compression spring 4 generates axial pressure, which pushes the spring pressure seat 5 to squeeze the rotary pressure shaft seal 9, so that the inner diameter lip of the rotary pressure shaft seal 9 always keeps in close contact with the rotary shaft 1, realizing dynamic pressure sealing, forming a second-level seal, and can compensate for wear. It can prevent seal failure caused by pressure fluctuation or centrifugal force when the equipment is running at high speed (when running at high speed, the rotary seal ring with the inclined surface may fail under the action of centrifugal force. At this time, the pressure in the sealing shell will also fluctuate. The seal is achieved by the interference fit between the inner diameter of the rotary pressure shaft seal and the rotary shaft, and the outer diameter of the seal and the sealing shell, and by the axial pressure applied by the spring clamping mechanism, which can prevent seal failure caused by pressure change).

[0058] 3) The inner diameter of the radial lip seal 10 is tightly fitted with the rotating shaft 1 to achieve a third-level seal as a final protection, to intercept the very little solvent that may penetrate the first two levels of seal and prevent the solvent from entering the motor.

[0059] The axial sealing device of the rotating mechanism in this embodiment of the invention is suitable for speed ranges of 1500~4500 rpm. When applied to a powder flattening device (e.g., a rotating shaft with a diameter of 25 mm), the powder and alcohol enter the working chamber of the device via a peristaltic pump. The V-shaped rotating seal ring fits tightly against the pressure cap, forming a sealing surface that prevents the solution from entering the motor shaft. Simultaneously, the motor drives the rotating shaft to rotate, which in turn drives the V-shaped rotating seal ring to rotate, generating centrifugal force to further isolate the solution within the working chamber. If a small portion of the solution passes through the V-shaped rotating seal ring, this portion will enter the sealed cooling chamber. Under the action of the spring-pressurized structure, the rotating pressure shaft seal will always maintain a tight fit with the rotating shaft, thereby preventing further leakage towards the motor. At this point, almost no solution continues to leak downwards. If a very small amount of solution still leaks, a radial lip seal ring will provide final protection, isolating the solution here and preventing further leakage towards the motor. Multiple experiments were conducted on this invention within the rotating shaft speed range of 1500 rpm to 4500 rpm, and no solvent leakage occurred.

[0060] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A rotary mechanism axial seal device for sealing the axial direction of a rotary shaft (1) against leakage of a medium in a working chamber along the rotary shaft (1) in the direction of a driving mechanism that drives the rotary shaft to rotate, characterized by, include: The first-stage sealing unit is located on the side near the working chamber and includes a rotating sealing ring (2) with an inclined surface and a pressure cap (7). The rotating sealing ring (2) with an inclined surface is fitted onto the rotating shaft (1), and its inclined surface is tightly fitted with the end face of the pressure cap (7) under the axial pressure of the rotating shaft (1) to form an end face seal. The second-stage sealing unit, located near the drive mechanism, includes a rotary pressure shaft seal (9), a spring clamping mechanism, and a sealing housing (8). The sealing housing (8) is fitted onto the rotary shaft (1). Both the rotary pressure shaft seal (9) and the spring clamping mechanism are located within the sealing housing (8). The inner diameter of the rotary pressure shaft seal (9) is interference-fitted with the rotary shaft (1), and its outer diameter is interference-fitted with the sealing housing (8). The spring clamping mechanism applies continuous axial pressure to the rotary pressure shaft seal (9) to ensure that the inner diameter of the rotary pressure shaft seal (9) remains in close contact with the rotary shaft (1). The third-level sealing unit includes a radial lip seal (10) and the sealing housing (8); the radial lip seal (10) is disposed inside the sealing housing (8) and is closer to the drive mechanism than the rotary pressure shaft seal (9), its inner diameter is interference-fitted with the rotary shaft (1) and its outer diameter is interference-fitted with the sealing housing (8).

2. The axial sealing device for the rotating mechanism as described in claim 1, characterized in that, The spring clamping mechanism includes a spring base (3), a compression spring (4) and a spring pressure seat (5). The pressure cover (7) is fixed inside the sealing housing (8). The spring base (3) is fixed on the pressure cover (7). One end of the compression spring (4) is connected to the spring base (3), and the other end applies axial pressure to the rotating pressure shaft seal (9) through the spring pressure seat (5), so that the inner diameter of the rotating pressure shaft seal (9) is always tightly fitted with the rotating shaft (1).

3. The axial sealing device for the rotating mechanism as described in claim 2, characterized in that, The axial pressure provided by the compression spring (4) is configured such that the radial force between the rotating pressure shaft seal (9) and the rotating shaft (1) is in the range of 1N / cm-2N / cm.

4. The axial sealing device for the rotating mechanism as described in claim 3, characterized in that, The axial pressure provided by the compression spring (4) is configured such that when the linear velocity of the rotating shaft (1) is ≤4m / s, the radial force between the rotating pressure shaft seal (9) and the rotating shaft (1) is in the range of 1.5N / cm-2N / cm; and when the linear velocity of the rotating shaft (1) is >4m / s, the radial force between the rotating pressure shaft seal (9) and the rotating shaft (1) is in the range of 1N / cm-1.5N / cm.

5. The axial sealing device for the rotating mechanism as described in claim 2, characterized in that, The spring base (3) and the spring pressure seat (5) are both annular and are sleeved on the rotating shaft (1). A plurality of compression springs (4) are evenly distributed between the spring base (3) and the spring pressure seat (5).

6. The axial sealing device for the rotating mechanism as described in claim 1, characterized in that, The sealed housing (8) includes a sealed cooling chamber (81) and a cooling chamber sealing cover plate (6). The cooling chamber sealing cover plate (6) is connected to the sealed cooling chamber (81) to seal the cooling medium inside the sealed cooling chamber (81). The sealed cooling chamber (81) is provided with a cooling medium inlet (811) and a cooling medium outlet (812).

7. The axial sealing device for a rotating mechanism as described in claim 1, characterized in that, The material of the inclined rotary seal ring (2) is fluororubber; the material of the rotary pressure shaft seal (9) is polytetrafluoroethylene plus carbon fiber composite material; and the material of the radial lip seal ring (10) is fluororubber.

8. The axial sealing device for a rotating mechanism as described in claim 1, characterized in that, The rotary sealing ring (2) with an inclined surface is a V-shaped rotary sealing ring; the radial lip sealing ring (10) is a skeleton oil seal; the rotary pressure shaft seal (9) has a V-shaped groove (91), the V-shaped groove (91) is installed facing the working chamber and the V-shaped surface is in contact with the spring clamping mechanism.

9. A method for axial sealing of a rotating mechanism, employing the axial sealing device for a rotating mechanism as described in any one of claims 1-8, characterized in that, Includes the following steps: 1) The first-level seal is achieved by the tight fit between the inclined rotary sealing ring (2) and the gland (7) to isolate the medium in the working chamber when the equipment is running at low speed; 2) The spring clamping mechanism applies axial pressure to the rotary pressure shaft seal (9) so that the inner diameter of the rotary pressure shaft seal (9) always keeps in close contact with the rotary shaft (1) to achieve a second-level seal, so as to compensate for wear and prevent seal failure caused by pressure fluctuation or centrifugal force when the equipment is running at high speed. 3) The inner diameter of the radial lip seal (10) is tightly fitted with the rotating shaft (1) to achieve a third-level seal as the final protection.

10. The axial sealing method for a rotating mechanism as described in claim 9, characterized in that, In step 2), the axial pressure provided by the spring clamping mechanism makes the radial force between the rotating pressure shaft seal (9) and the rotating shaft (1) in the range of 1N / cm-2N / cm.

11. The axial sealing method for a rotating mechanism as described in claim 9, characterized in that, In step 2), when the linear velocity of the rotating shaft (1) is ≤4m / s, the radial force is in the range of 1.5N / cm-2N / cm; when the linear velocity of the rotating shaft (1) is >4m / s, the radial force is in the range of 1N / cm-1.5N / cm.

12. A powder flattening device, characterized in that, It includes a rotary mechanism axial sealing device as described in any one of claims 1 to 8.

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