A centrifuge, a main shaft rotating sealing structure and a sealing bushing thereof

Abstract

This utility model relates to the field of separation equipment technology, specifically to a centrifuge, a main shaft rotary seal structure and its sealing bushing, and a main shaft. The sealing bushing of the main shaft rotary seal structure includes a bushing fixing part for fitting and fixing onto the main shaft fixing part, and a bushing mating part for mating with a portion of the main shaft having a main shaft anti-corrosion layer. The bushing mating part has bushing mating surfaces that are spaced apart from the main shaft mating surface. The bushing anti-corrosion layer includes an outer peripheral anti-corrosion layer on the outer circumferential surface of the sealing bushing and a mating surface anti-corrosion layer on the bushing mating surface. The outer peripheral anti-corrosion layer has a portion for sealing with a rotary seal, and the mating surface anti-corrosion layer forms a sealing fit with the portion of the main shaft anti-corrosion layer on the main shaft mating surface through an inner seal. This achieves a continuous anti-corrosion layer between the main shaft and the sealing bushing, avoiding discontinuities that could lead to exposed metal, improving corrosion resistance, and ensuring reliable operation.

Description

Technical Field

[0001] This utility model relates to the field of separation equipment technology, specifically to a centrifuge, a main shaft rotary sealing structure and its sealing bushing, and a main shaft. Background Technology

[0002] Centrifuges are widely used separation equipment in the chemical industry. They achieve separation by generating centrifugal force through a high-speed rotating drum. A centrifuge consists of a shell, a rotating drum, a main shaft, and a power source. The power source drives the rotating drum to rotate at high speed via the main shaft.

[0003] The spindle comes into contact with corrosive liquids or gases. Existing technologies include a corrosion-resistant coating on the spindle surface and a sealing bushing installed on the spindle to cooperate with the rotary seal and the fixed components of the centrifuge to form a rotary seal structure. Using the spindle with the bushing reduces wear and vibration, and also facilitates equipment maintenance and simplifies equipment structure and manufacturing processes. However, since the bushing also comes into contact with corrosive liquids or gases, existing technologies use a corrosion-resistant coating on the outer surface of the bushing. For example, Chinese Utility Model Patent Application No. 201920646638.0 discloses a wear-resistant sealing bushing for an industrial washing machine spindle, used to increase the service life of the wear-resistant bushing and the spindle sealing structure.

[0004] However, because the bushing and spindle need to withstand axial and radial pressure, and the anti-corrosion coating can be crushed under pressure, this results in exposed metal at the joint between the bushing and spindle, reducing corrosion resistance and affecting service life. In chemical equipment, many highly corrosive environments exist, and any exposed metal point poses a significant risk. Utility Model Content

[0005] The purpose of this invention is to provide a spindle rotary seal structure to solve the problem that the corrosion resistance of the current spindle rotary seal structure is reduced due to metal exposure points between the anti-corrosion layers of the spindle and the sealing bushing. The purpose of this invention is also to provide a sealing bushing, a spindle, and a centrifuge using the spindle rotary seal structure to solve the above problems.

[0006] The technical solution for the sealing bushing of the spindle rotary sealing structure of this utility model is as follows: A sealing bushing for a spindle rotary seal structure includes a bushing fixing part for fitting and fixing onto a spindle fixing part, and a bushing mating part for engaging with a portion of the spindle having a spindle anti-corrosion layer. The bushing mating part has bushing mating surfaces that are spaced apart from the spindle mating surfaces. The sealing bushing is provided with a bushing anti-corrosion layer, which includes an outer peripheral anti-corrosion layer on the outer circumferential surface of the sealing bushing and a mating surface anti-corrosion layer on the bushing mating surface. The outer peripheral anti-corrosion layer and the mating surface anti-corrosion layer are continuous. The outer peripheral anti-corrosion layer has a portion for sealing engagement with a rotary seal, and the mating surface anti-corrosion layer is used to form a sealing engagement with the portion of the spindle anti-corrosion layer on the spindle mating surface through an inner seal.

[0007] Furthermore, the bushing mating surface is the inner circumferential surface of the bushing mating part that is opposite to the outer circumferential surface of the spindle, and the bushing anti-corrosion layer includes an end face anti-corrosion layer located on one end face of the sealing bushing that faces the sealing cavity, and the end face anti-corrosion layer is connected to the outer circumferential surface anti-corrosion layer and the mating surface anti-corrosion layer.

[0008] Furthermore, the sealing bushing includes a large hole section and a small hole section. The inner diameter of the large hole section is larger than that of the small hole section. An inner step is formed at the junction of the large hole section and the small hole section for abutting against the outer step on the spindle. The bushing mating part is located in the large hole section, and the bushing fixing part is located in the small hole section. The small hole section is used for transition mating with the spindle.

[0009] Furthermore, the outer diameter of the larger hole section is larger than that of the smaller hole section, and the outer circumferential surface of the larger hole section is connected to the outer circumferential surface of the smaller hole section through a conical surface.

[0010] Furthermore, the bushing mating part is provided with an annular sealing groove for the inner sealing element to be installed.

[0011] Furthermore, the portion of the sealing bushing used for sealing engagement with the inner seal and the portion used for sealing engagement with the rotary seal are spaced apart axially.

[0012] Beneficial Effects: This utility model innovatively provides a rotary sealing structure for a spindle that allows the anti-corrosion layer of the spindle to be connected to the anti-corrosion layer of the sealing bushing. It features spaced-apart mating surfaces on the spindle and the sealing bushing, preventing the anti-corrosion layers on these surfaces from being crushed or damaged. An inner seal is installed between them, sealing the anti-corrosion layers on both surfaces. This inner seal connects the anti-corrosion layers of the spindle and the bushing, preventing discontinuity and metal exposure, improving corrosion resistance, and ensuring reliable operation.

[0013] The technical solution for the spindle of this utility model's spindle rotary sealing structure is as follows: A spindle with a rotary sealing structure includes a spindle fixing part for fitting and fixing a bushing fixing part for a sealing bushing, and a spindle mating part for engaging with a portion of the sealing bushing having a bushing anti-corrosion layer. The spindle mating part has a spindle mating surface that is spaced apart from the bushing mating surface of the sealing bushing. The spindle is provided with a spindle anti-corrosion layer, which includes a portion located on the spindle mating surface and is used to form a sealing engagement with the portion of the bushing anti-corrosion layer located on the bushing mating surface through an inner seal.

[0014] Furthermore, the main spindle mating surface is the outer peripheral surface of the main spindle mating part that is opposite to the inner peripheral surface of the sealing bushing.

[0015] Furthermore, the spindle includes a large diameter section and a small diameter section. The diameter of the large diameter section is larger than that of the small diameter section. An outer step is formed at the junction of the large diameter section and the small diameter section for abutting against the inner step of the sealing bushing. The spindle mating part is located in the large diameter section, and the spindle fixing part is located in the small diameter section. The small diameter section is used for transition mating with the sealing bushing.

[0016] Furthermore, the spindle mating part is provided with an annular sealing groove for the inner seal to be installed, and the anti-corrosion layer of the spindle includes the portion located on the inner wall surface of the annular sealing groove.

[0017] Beneficial Effects: This utility model innovatively provides a rotary sealing structure for a spindle that allows the anti-corrosion layer of the spindle to be connected to the anti-corrosion layer of the sealing bushing. It features spaced-apart mating surfaces on the spindle and the sealing bushing, preventing the anti-corrosion layers on these surfaces from being crushed or damaged. An inner seal is installed between them, sealing the anti-corrosion layers on both surfaces. This inner seal connects the anti-corrosion layers of the spindle and the bushing, preventing discontinuity and metal exposure, improving corrosion resistance, and ensuring reliable operation.

[0018] The technical solution of the spindle rotary sealing structure of this utility model is as follows: A spindle rotary seal structure includes a spindle and a sealing bushing fixedly mounted on the spindle. The sealing bushing forms a rotary seal with corresponding mating parts through a rotary seal element. An inner seal element is provided between the sealing bushing and the spindle. The sealing bushing includes a bushing fixing part for fitting and fixing onto the spindle fixing part, and a bushing mating part for mating with a portion of the spindle having a spindle anti-corrosion layer. The bushing mating part has a bushing mating surface that is spaced apart from the spindle mating surface of the spindle. The sealing bushing is provided with a bushing anti-corrosion layer, which includes an outer peripheral anti-corrosion layer on the outer peripheral surface of the sealing bushing and a mating surface anti-corrosion layer on the mating surface of the bushing. The outer peripheral anti-corrosion layer and the mating surface... The anti-corrosion layer is continuous, and the outer peripheral anti-corrosion layer has a portion for sealing with the rotary seal. The mating surface anti-corrosion layer is used to form a sealing fit with the portion of the spindle anti-corrosion layer located on the spindle mating surface through the inner seal. The spindle includes a spindle fixing part for sleeve and fixing the bushing fixing part of the sealing bushing and a spindle mating part for mating with the portion of the sealing bushing with the bushing anti-corrosion layer. The spindle mating part has a spindle mating surface that is spaced apart from the bushing mating surface of the sealing bushing. The spindle is provided with a spindle anti-corrosion layer, which includes a portion located on the spindle mating surface and is used to form a sealing fit with the portion of the bushing anti-corrosion layer located on the bushing mating surface through the inner seal.

[0019] Furthermore, the bushing mating surface is the inner circumferential surface of the bushing mating part that is opposite to the outer circumferential surface of the spindle, and the bushing anti-corrosion layer includes an end face anti-corrosion layer located on one end face of the sealing bushing that faces the sealing cavity, and the end face anti-corrosion layer is connected to the outer circumferential surface anti-corrosion layer and the mating surface anti-corrosion layer.

[0020] Furthermore, the sealing bushing includes a large hole section and a small hole section. The inner diameter of the large hole section is larger than that of the small hole section. An inner step is formed at the junction of the large hole section and the small hole section for abutting against the outer step on the spindle. The bushing mating part is located in the large hole section, and the bushing fixing part is located in the small hole section. The small hole section is used for transition mating with the spindle.

[0021] Furthermore, the outer diameter of the larger hole section is larger than that of the smaller hole section, and the outer circumferential surface of the larger hole section is connected to the outer circumferential surface of the smaller hole section through a conical surface.

[0022] Furthermore, the bushing mating part is provided with an annular sealing groove for the inner sealing element to be installed.

[0023] Furthermore, the portion of the sealing bushing used for sealing engagement with the inner seal and the portion used for sealing engagement with the rotary seal are spaced apart axially.

[0024] Furthermore, the main spindle mating surface is the outer peripheral surface of the main spindle mating part that is opposite to the inner peripheral surface of the sealing bushing.

[0025] Furthermore, the spindle includes a large diameter section and a small diameter section. The diameter of the large diameter section is larger than that of the small diameter section. An outer step is formed at the junction of the large diameter section and the small diameter section for abutting against the inner step of the sealing bushing. The spindle mating part is located in the large diameter section, and the spindle fixing part is located in the small diameter section. The small diameter section is used for transition mating with the sealing bushing.

[0026] Furthermore, the spindle mating part is provided with an annular sealing groove for the inner seal to be installed, and the anti-corrosion layer of the spindle includes the portion located on the inner wall surface of the annular sealing groove.

[0027] Beneficial Effects: This utility model innovatively provides a rotary sealing structure for a spindle that allows the anti-corrosion layer of the spindle to be connected to the anti-corrosion layer of the sealing bushing. It features spaced-apart mating surfaces on the spindle and the sealing bushing, preventing the anti-corrosion layers on these surfaces from being crushed or damaged. An inner seal is installed between them, sealing the anti-corrosion layers on both surfaces. This inner seal connects the anti-corrosion layers of the spindle and the bushing, preventing discontinuity and metal exposure, improving corrosion resistance, and ensuring reliable operation.

[0028] The technical solution of this utility model centrifuge is: A centrifuge includes a main shaft for driving a rotating drum and a sealing bushing fixedly mounted on the main shaft. The sealing bushing forms a rotary seal with a fixed component via a rotary seal. The fixed component includes a housing, and the rotating drum is mounted inside the housing. An inner seal is provided between the sealing bushing and the main shaft. The sealing bushing includes a bushing fixing part for fitting and fixing onto a main shaft fixing part of the main shaft, and a bushing mating part for engaging with a portion of the main shaft having a main shaft anti-corrosion layer. The bushing mating part has bushing mating surfaces that are spaced apart from the main shaft mating surfaces. The sealing bushing is provided with a bushing anti-corrosion layer, which includes an outer peripheral surface anti-corrosion layer located on the outer circumferential surface of the sealing bushing and a mating surface anti-corrosion layer located on the bushing mating surface. The peripheral anti-corrosion layer and the mating surface anti-corrosion layer are continuous. The outer peripheral anti-corrosion layer has a portion for sealing with the rotary seal. The mating surface anti-corrosion layer is used to form a sealing fit with the portion of the spindle anti-corrosion layer located on the spindle mating surface through the inner seal. The spindle includes a spindle fixing part for sleeve and fixing the bushing fixing part of the sealing bushing and a spindle mating part for mating with the portion of the sealing bushing with the bushing anti-corrosion layer. The spindle mating part has a spindle mating surface that is spaced apart from the bushing mating surface of the sealing bushing. The spindle is provided with a spindle anti-corrosion layer, which includes a portion located on the spindle mating surface and is used to form a sealing fit with the portion of the bushing anti-corrosion layer located on the bushing mating surface through the inner seal.

[0029] Furthermore, the bushing mating surface is the inner circumferential surface of the bushing mating part that is opposite to the outer circumferential surface of the spindle, and the bushing anti-corrosion layer includes an end face anti-corrosion layer located on one end face of the sealing bushing that faces the sealing cavity, and the end face anti-corrosion layer is connected to the outer circumferential surface anti-corrosion layer and the mating surface anti-corrosion layer.

[0030] Furthermore, the sealing bushing includes a large hole section and a small hole section. The inner diameter of the large hole section is larger than that of the small hole section. An inner step is formed at the junction of the large hole section and the small hole section for abutting against the outer step on the spindle. The bushing mating part is located in the large hole section, and the bushing fixing part is located in the small hole section. The small hole section is used for transition mating with the spindle.

[0031] Furthermore, the outer diameter of the larger hole section is larger than that of the smaller hole section, and the outer circumferential surface of the larger hole section is connected to the outer circumferential surface of the smaller hole section through a conical surface.

[0032] Furthermore, the bushing mating part is provided with an annular sealing groove for the inner sealing element to be installed.

[0033] Furthermore, the portion of the sealing bushing used for sealing engagement with the inner seal and the portion used for sealing engagement with the rotary seal are spaced apart axially.

[0034] Furthermore, the main spindle mating surface is the outer peripheral surface of the main spindle mating part that is opposite to the inner peripheral surface of the sealing bushing.

[0035] Furthermore, the spindle includes a large diameter section and a small diameter section. The diameter of the large diameter section is larger than that of the small diameter section. An outer step is formed at the junction of the large diameter section and the small diameter section for abutting against the inner step of the sealing bushing. The spindle mating part is located in the large diameter section, and the spindle fixing part is located in the small diameter section. The small diameter section is used for transition mating with the sealing bushing.

[0036] Furthermore, the spindle mating part is provided with an annular sealing groove for the inner seal to be installed, and the anti-corrosion layer of the spindle includes the portion located on the inner wall surface of the annular sealing groove.

[0037] Beneficial Effects: This utility model innovatively provides a rotary sealing structure for a spindle that allows the anti-corrosion layer of the spindle to be connected to the anti-corrosion layer of the sealing bushing. It features spaced-apart mating surfaces on the spindle and the sealing bushing, preventing the anti-corrosion layers on these surfaces from being crushed or damaged. An inner seal is installed between them, sealing the anti-corrosion layers on both surfaces. This inner seal connects the anti-corrosion layers of the spindle and the bushing, preventing discontinuity and metal exposure, improving corrosion resistance, and ensuring reliable operation. Attached Figure Description

[0038] Figure 1This is a schematic diagram of an embodiment of the spindle rotary sealing structure of this utility model; Figure 2 for Figure 1 A schematic diagram of the mating structure between the spindle and the sealing bushing; Figure 3 for Figure 1 A cross-sectional schematic diagram of the sealing bushing.

[0039] In the figure: 1. Spindle; 11. Spindle base; 12. Spindle anti-corrosion layer; 2. Sealing bushing; 21. Bushing base; 22. Bushing anti-corrosion layer; 23. Annular groove; 24. Inner step; 3. Inner seal; 4. Fixed component; 5. Rotary seal; 6. Bearing. Detailed Implementation

[0040] The basic concept of this utility model's spindle rotary sealing structure is to set spaced-apart mating surfaces on the spindle and the sealing bushing, and to install an inner seal between them. The inner seal engages with the anti-corrosion layers on the spindle mating surface and the bushing mating surface to achieve a continuous anti-corrosion layer between the spindle and the sealing bushing, avoiding discontinuity that could lead to exposed metal, improving corrosion resistance, ensuring reliable use, and extending service life.

[0041] The technical solution of this utility model will be described in detail below with reference to specific embodiments.

[0042] An embodiment of the spindle rotary sealing structure of this utility model: like Figure 1 , Figure 2 , Figure 3 As shown in the figure, the colors are only for ease of understanding of the technical solution and to make the various components more intuitive, and do not limit the technical solution. The spindle rotary seal structure includes a spindle 1, a sealing bushing 2, an inner seal 3, a fixed component 4, and a rotary seal 5. The sealing bushing 2 is fixedly installed on the spindle 1. The sealing bushing 2 forms a rotary seal with the corresponding mating component through the rotary seal 5. Both the spindle 1 and the sealing bushing 2 are provided with anti-corrosion layers to prevent corrosion from gas or liquid in the sealing cavity.

[0043] In this embodiment, the spindle rotary seal structure is used in a centrifuge. Correspondingly, the spindle 1 is the rotating shaft of a drum, and the sealing bushing 2 rotates with the spindle 1. The corresponding mating component that forms a rotary seal with the sealing bushing 2 is a fixed component 4. The fixed component 4 includes components that do not rotate during use, such as a housing and bearing seats. The inner cavity of the housing forms the sealing cavity of the fixed component 4, and the drum is located within the inner cavity of the housing. The spindle 1 performs a rotary seal at the point where it passes through the fixed component 4. At least one end of the spindle 1 at both its upper and lower ends is rotatably supported on the bearing seat of the fixed component 4 via bearings 6. The sealing bushing 2 is located on the side of the bearing 6 closest to the sealing cavity. This spindle rotary seal structure can be used at both the upper and lower ends of the spindle 1. Figure 1 The diagram shows a rotary seal structure formed by the upper end of the main shaft 1 and the upper sidewall of the fixed component 4; the lower end may have a symmetrical structure. In other embodiments, the rotary seal structure can also be used on a centrifugal extractor or a stirrer.

[0044] The sealing bushing 2 has two axial ends, one of which is close to the sealing cavity and forms the inner end, and the other end facing away from the sealing cavity and forms the outer end. The inner end will come into contact with the gas or liquid inside the sealing cavity, while the outer end will not come into contact with the gas or liquid inside the sealing cavity due to the isolation of the rotary seal 5. The inner wall of the mounting hole of the fixing component 4 through which the sealing bushing 2 and the main shaft 1 pass is provided with a mounting groove for mounting the rotary seal 5. The rotary seal 5 is in sealing fit with the outer circumferential surface of the sealing bushing 2. The rotary seal 5 is a skeleton oil seal, and one, two, or more seals can be set along the axial direction. The skeleton oil seal is a lip seal, which has good sealing performance, compact structure, and can adapt to certain eccentricity and shaft non-roundness.

[0045] The sealing bushing 2 is a steel-lined ceramic bushing, comprising a bushing substrate 21 and a bushing anti-corrosion layer 22. The bushing substrate 21 is made of steel, as shown in the orange portion of the figure. The bushing anti-corrosion layer 22 is a ceramic coating, but it can also be an enamel coating, Teflon coating, or PTFE coating, as shown in the dark blue portion of the figure. The spindle 1 includes a spindle substrate 11 and a spindle anti-corrosion layer 12. The spindle substrate 11 is shown in the figure. Figure 2 The light blue portion refers to the anti-corrosion layer 12 on the main spindle. Figure 2 The black part in the middle.

[0046] The sealing bushing 2 includes a bushing fixing part for fitting and fixing onto the spindle fixing part of the spindle 1. The sealing bushing 2 also includes a bushing mating part for engaging with a portion of the spindle 1 that has a spindle anti-corrosion layer 12. The bushing mating part has bushing mating surfaces that are spaced apart from the spindle mating surface of the spindle 1. The bushing anti-corrosion layer 22 includes an outer peripheral anti-corrosion layer on the outer circumferential surface of the sealing bushing 2 and a mating surface anti-corrosion layer on the mating surface. The outer peripheral anti-corrosion layer and the mating surface anti-corrosion layer are continuous. The outer peripheral anti-corrosion layer has a portion for sealing with the rotary seal 5. The mating surface anti-corrosion layer of the sealing bushing 2 forms a sealing engagement with the portion of the spindle anti-corrosion layer 12 located on the spindle mating surface through the inner seal 3.

[0047] The spindle 1 includes a spindle fixing part for fitting and fixing the bushing fixing part of the sealing bushing 2. The spindle 1 also includes a spindle mating part for engaging with a portion of the sealing bushing 2 that has a bushing anti-corrosion layer 22. The spindle mating part has a spindle mating surface that is spaced apart from the bushing mating surface of the sealing bushing 2. The spindle anti-corrosion layer 12 includes a portion located on the spindle mating surface, and this portion is used to form a sealing engagement with the portion of the bushing anti-corrosion layer 22 located on the bushing mating surface through the inner seal 3. The portion of the bushing anti-corrosion layer 22 located on the bushing mating surface is its mating surface anti-corrosion layer.

[0048] Because the spindle mating surface and the bushing mating surface are spaced apart and opposite each other, the anti-corrosion layers on the spindle mating surface and the bushing mating surface will not be squeezed and damaged. At the same time, an inner seal 3 is installed between them. The inner seal 3 seals and engages with the anti-corrosion layers on the spindle mating surface and the bushing mating surface respectively, so that the anti-corrosion layers of the two are connected through the inner seal 3. This achieves the connection of the anti-corrosion layers of the spindle 1 and the sealing bushing 2, avoids the appearance of exposed metal points at the discontinuity, improves the anti-corrosion capability, and ensures reliable use.

[0049] The bushing mating part of the sealing bushing 2 is the portion near its inner end. The bushing mating part is fitted onto the spindle mating part with a clearance. The inner circumferential surface of the bushing mating part forms the bushing mating surface. The inner circumferential surface of the bushing mating part faces the outer circumferential surface of the spindle mating part and is sealed by the inner seal 3. The outer circumferential surface of the spindle mating part forms the spindle mating surface. The inner diameter of the bushing mating part is slightly larger than the outer diameter of the spindle mating part, forming a clearance fit. The end face of the sealing bushing 2 facing the sealing cavity is its inner end face. The bushing anti-corrosion layer 22 includes an end face anti-corrosion layer located on its inner end face. The end face anti-corrosion layer is connected to the outer circumferential surface anti-corrosion layer and the mating surface anti-corrosion layer. The mating surface anti-corrosion layer is the inner circumferential surface anti-corrosion layer. The bushing anti-corrosion layer 22 extends continuously from the outer circumferential surface of the sealing bushing 2 through the inner end face to the inner circumferential surface. The sealing bushing 2 and the spindle 1 form a circumferential seal through the inner seal 3, which is beneficial for reliable sealing. In other embodiments, the spindle may have a stepped surface that is axially opposite to the end face of the inner end of the sealing bushing. The end face of the inner end of the sealing bushing forms a bushing mating surface, and the stepped surface on the spindle forms a spindle mating surface. The bushing mating surface and the spindle mating surface form an end face seal through an inner seal.

[0050] The sealing bushing 2 includes a large-diameter section and a small-diameter section. The inner diameter of the large-diameter section is larger than that of the small-diameter section. An inner step 24 is formed at the junction of the large-diameter section and the small-diameter section for abutting against the outer step on the main shaft 1. The bushing mating part is located in the large-diameter section, and the bushing fixing part is located in the small-diameter section. The small-diameter section is used for transition fit with the main shaft 1. The main shaft 1 includes a large-diameter section and a small-diameter section. The diameter of the large-diameter section is larger than that of the small-diameter section. The main shaft 1 is a hollow shaft, and this diameter is the outer diameter. An outer step is formed at the junction of the large-diameter section and the small-diameter section for axial abutting against the inner step 24 of the sealing bushing 2. The main shaft mating part is located in the large-diameter section, and the main shaft fixing part is located in the small-diameter section. The small-diameter section of the main shaft 1 is transition fit with the small-diameter section of the sealing bushing 2. The bearing 6 is installed on the small-diameter section of the main shaft 1. The stepped fit can withstand axial force. In other embodiments, the step can be omitted, the diameter of the main shaft is the same at all parts, the inner diameter of the bushing fit of the sealing bushing is slightly larger than the inner diameter of the bushing fixing part, and the inner circumferential surface of the bushing fit and the inner circumferential surface of the bushing fixing part are smoothly transitioned.

[0051] The outer diameter of the large-hole section of the sealing bushing 2 is larger than that of the small-hole section. The outer circumferential surface of the large-hole section transitions to the outer circumferential surface of the small-hole section through a conical surface, which helps to ensure that the sealing bushing 2 has sufficient wall thickness and saves space. In other embodiments, the outer diameter of the large-hole section of the sealing bushing can also be the same as that of the small-hole section.

[0052] It should be noted that, for example, an annular groove 23 is provided on the inner wall of the sealing bushing 2 on the side away from the inner end of the bushing mating surface. The annular groove 23 is located on the inner circumferential surface of the large hole section. The portion of the inner circumferential surface of the large hole section near the inner end constitutes the bushing mating surface. The annular groove 23 connects with the inner step 24. The inner circumferential surface of the bushing fixing part and the inner wall surface of the annular groove 23 do not have an anti-corrosion layer. Because precise edge finishing is not possible during ceramic spraying, the annular groove 23 is set to form a coating spraying finishing groove, allowing a transition area before the coating is sprayed onto the step surface, which has a marking effect on the spraying operation.

[0053] For example, the bushing mating part is provided with an annular sealing groove for the inner sealing element to be installed. The annular sealing groove is located on the inner circumferential surface of the large hole section. The annular sealing groove on the inner circumferential surface of the large hole section has an marking effect, which helps to determine the area where the coating is applied on the bushing mating surface and facilitates processing.

[0054] The portion of the sealing bushing 2 used for sealing with the inner seal 3 and the portion used for sealing with the rotary seal 5 are spaced apart axially. The inner wall of the large-hole section of the sealing bushing 2 forms a static seal with the main shaft 1 through the inner seal 3, and the outer wall of the small-hole section of the sealing bushing 2 forms a dynamic seal with the fixed component 4 through the rotary seal 5. In other embodiments, the outer peripheral surface of the bushing mating part can also form a rotary seal with the fixed component.

[0055] In this embodiment, the spindle mating part is provided with an annular sealing groove for the inner seal 3 to be installed, and the spindle anti-corrosion layer 12 includes a portion located on the inner wall surface of the annular sealing groove. The inner seal 3 adopts an O-ring seal, and the annular sealing groove is provided with two grooves to install two sealing rings, ensuring sealing performance. In other embodiments, the sealing groove can also be provided on the sealing bushing, and the annular sealing groove can be provided with only one groove to install one sealing ring, or with three or more grooves to install multiple sealing rings.

[0056] The spindle 1, sealing bushing 2, and inner seal 3 rotate together. The inner seal 3 adheres and presses tightly against the ceramic coating on the sealing bushing 2 and the anti-corrosion coating on the spindle 1. The rotary seal 5 and the ceramic coating on the sealing bushing 2 form a dynamic seal. The roughness of the part of the bushing anti-corrosion layer 22 used for sealing with the rotary seal 5 is less than the roughness of the other parts, which are the parts of the bushing anti-corrosion layer that do not mate with the seal during use. After the ceramic coating is sprayed, the surface used to mate with the rotary seal 5 is precision ground using a grinding machine. The other outer surfaces are the original sprayed surfaces and are relatively rough. The inner surface can be coarsely ground based on the original sprayed surface, or it can be left unground, as long as it is pressed tightly against the O-ring. The bushing fixing part of the sealing bushing 2 is precisely matched with the spindle fixing part of the spindle 1. The axially perpendicular surface of the inner step 24 of the sealing bushing 2 presses tightly against the axially perpendicular surface of the outer step on the spindle 1, thus completing the bearing capacity of the steel-lined ceramic bushing. This ensures that the bushing anti-corrosion layer 22 and the spindle anti-corrosion layer 12 do not bear the bearing pressure, but are supported by the steel substrate.

[0057] The transition of the anti-corrosion layer without exposed metal points is completed by the internal seal, which greatly improves the anti-corrosion performance of the dynamic seal structure and enhances the applicability of the spindle rotary seal structure in highly corrosive environments.

[0058] An embodiment of the sealing bushing of the spindle rotary sealing structure of this utility model: The sealing bushing of the spindle rotary sealing structure in this embodiment is the same as the sealing bushing structure in the above embodiment of the spindle rotary sealing structure, and will not be described again here.

[0059] An embodiment of the spindle with the spindle rotary sealing structure of this utility model: The spindle of the spindle rotary seal structure in this embodiment is the same as the spindle structure in the embodiment of the spindle rotary seal structure described above, and will not be described again here.

[0060] Embodiments of the centrifuge of this utility model: The centrifuge adopts the spindle rotary seal structure in the above embodiment. The centrifuge includes a spindle for driving the drum to rotate and a sealing bushing fixedly installed on the spindle. The sealing bushing forms a rotary seal with the fixed component through a rotary seal. The fixed component includes a housing, and the drum is installed in the housing. An inner seal is provided between the sealing bushing and the spindle. The sealing bushing has the same structure as the sealing bushing in the above embodiment of the spindle rotary seal structure. The spindle has the same structure as the spindle in the above embodiment of the spindle rotary seal structure, and will not be described again here.

[0061] Finally, it should be noted that the above description is only a preferred embodiment of this utility model and is not intended to limit this utility model. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still make modifications to the technical solutions described in the foregoing embodiments without creative effort, or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A sealing bushing for a spindle rotary sealing structure, characterized in that, The sealing bushing includes a bushing fixing part for fitting and fixing onto the main spindle fixing part, and a bushing mating part for engaging with a portion of the main spindle having a main spindle anti-corrosion layer. The bushing mating part has a bushing mating surface that is spaced apart from the main spindle mating surface. The sealing bushing is provided with a bushing anti-corrosion layer, which includes an outer peripheral anti-corrosion layer located on the outer peripheral surface of the sealing bushing and a mating surface anti-corrosion layer located on the bushing mating surface. The outer peripheral anti-corrosion layer and the mating surface anti-corrosion layer are continuous. The outer peripheral anti-corrosion layer has a portion for sealing engagement with a rotary seal. The mating surface anti-corrosion layer is used to form a sealing engagement with the portion of the main spindle anti-corrosion layer located on the main spindle mating surface through the inner seal.

2. The sealing bushing of the spindle rotary sealing structure according to claim 1, characterized in that, The bushing mating surface is the inner circumferential surface of the bushing mating part that is opposite to the outer circumferential surface of the spindle. The bushing anti-corrosion layer includes an end face anti-corrosion layer located on one end face of the sealing bushing that faces the sealing cavity. The end face anti-corrosion layer is connected to the outer circumferential surface anti-corrosion layer and the mating surface anti-corrosion layer.

3. The sealing bushing of the spindle rotary sealing structure according to claim 2, characterized in that, The sealing bushing includes a large hole section and a small hole section. The inner diameter of the large hole section is larger than that of the small hole section. An inner step is formed at the junction of the large hole section and the small hole section for abutting against the outer step on the spindle. The bushing mating part is located in the large hole section, and the bushing fixing part is located in the small hole section. The small hole section is used for transition mating with the spindle.

4. The sealing bushing of the spindle rotary sealing structure according to claim 3, characterized in that, The outer diameter of the larger hole section is larger than that of the smaller hole section, and the outer circumferential surface of the larger hole section is connected to the outer circumferential surface of the smaller hole section through a conical surface.

5. The sealing bushing of the spindle rotary sealing structure according to any one of claims 1-4, characterized in that, The bushing mating part is provided with an annular sealing groove for the inner sealing element to be installed.

6. The sealing bushing of the spindle rotary sealing structure according to any one of claims 1-4, characterized in that, The portion of the sealing bushing used for sealing with the inner seal and the portion used for sealing with the rotary seal are spaced apart axially.

7. A spindle with a rotary sealing structure, characterized in that, The spindle includes a spindle fixing part for fitting and fixing a bushing fixing part for a sealing bushing, and a spindle mating part for engaging with a portion of the sealing bushing that has a bushing anti-corrosion layer. The spindle mating part has a spindle mating surface that is spaced apart from the bushing mating surface of the sealing bushing. The spindle is provided with a spindle anti-corrosion layer, which includes a portion located on the spindle mating surface and is used to form a sealing engagement with the portion of the bushing anti-corrosion layer located on the bushing mating surface through an inner seal.

8. The spindle with the spindle rotary sealing structure according to claim 7, characterized in that, The main spindle mating surface is the outer circumferential surface of the main spindle mating part that is opposite to the inner circumferential surface of the sealing bushing.

9. The spindle with the spindle rotary sealing structure according to claim 8, characterized in that, The spindle includes a large diameter section and a small diameter section. The diameter of the large diameter section is larger than that of the small diameter section. An outer step is formed at the junction of the large diameter section and the small diameter section for abutting against the inner step of the sealing bushing. The spindle mating part is located in the large diameter section, and the spindle fixing part is located in the small diameter section. The small diameter section is used for transition mating with the sealing bushing.

10. The spindle with a rotary sealing structure according to claim 7, 8, or 9, characterized in that, The spindle mating part is provided with an annular sealing groove for the inner seal to be installed, and the anti-corrosion layer of the spindle includes the part located on the inner wall surface of the annular sealing groove.

11. A spindle rotary seal structure, comprising a spindle and a sealing bushing fixedly mounted on the spindle, wherein the sealing bushing forms a rotary seal with corresponding mating parts through a rotary sealing element, characterized in that, An inner seal is provided between the sealing bushing and the main shaft. The sealing bushing is the sealing bushing of the main shaft rotary sealing structure as described in any one of claims 1-6, and the main shaft is the main shaft of the main shaft rotary sealing structure as described in any one of claims 7-10.

12. A centrifuge, comprising a main shaft for driving a rotating drum and a sealing bushing fixedly mounted on the main shaft, the sealing bushing forming a rotary seal with a fixed component via a rotary seal, the fixed component including a housing, the rotating drum being mounted within the housing, characterized in that... An inner seal is provided between the sealing bushing and the main shaft. The sealing bushing is the sealing bushing of the main shaft rotary sealing structure as described in any one of claims 1-6, and the main shaft is the main shaft of the main shaft rotary sealing structure as described in any one of claims 7-10.

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