Magnetofluid mechanical sealing device and stirring equipment
By incorporating a magnetic fluid receiving ring and a double-blocking structure into the magnetic fluid mechanical seal device, the risks of wear debris contamination and leakage in existing sealing devices are resolved, achieving a high-purity and high-vacuum sealing effect and reducing operating costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-03
- Publication Date
- 2026-04-14
AI Technical Summary
Existing mechanical seal devices are prone to wear and contamination of materials after long-term operation. Non-contact seals are costly and have high operational requirements. Furthermore, the reliability of magnetohydrodynamic seal structures is insufficient, posing a risk of leakage and making it difficult to meet the process requirements of high vacuum and high purity.
A magnetic fluid receiving ring is set in the magnetic fluid mechanical seal device to form a magnetic fluid receiving cavity that can restrict the fluid, ensuring that even if the sealing structure fails, magnetic fluid leakage can be limited to avoid contaminating materials, and reliable sealing is achieved through a double barrier structure and monitoring device.
It effectively prevents magnetofluid leakage in material mixing devices requiring high purity, reduces operating costs, is suitable for high vacuum processes, and can replace contact and non-contact sealing devices.
Smart Images
Figure CN224120664U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of magnetic fluid sealing technology, specifically to a magnetic fluid mechanical sealing device and a stirring device. Background Technology
[0002] In filter washing and drying machines, traditional shaft seals typically employ mechanical seals, utilizing the end faces of rotating and stationary rings to achieve a seal between the shaft and the housing. This type of mechanical seal, with direct contact between the rotating and stationary rings, can lead to the formation of abrasive debris between the rings after prolonged operation. This debris can enter the equipment and contaminate materials. Currently, non-contact mechanical seals are also available, incorporating a venting structure to form a micron-level gas film for lubrication, achieving contactless operation. Compared to contact seals, this eliminates abrasion. However, non-contact mechanical seals are more expensive and require more precise operation; otherwise, there is a risk of contact between the rotating and stationary rings. Furthermore, these non-contact mechanical seals require a continuous supply of clean nitrogen during operation, resulting in higher operating costs. Additionally, they may prevent the equipment from achieving a sufficiently high vacuum level, making them unsuitable for processes requiring high vacuum.
[0003] Furthermore, magnetohydrodynamic (MHD) seals form a closed magnetic flux loop through the magnetic lines of force of the poles, shaft, and magnetohydrodynamic fluid, holding the magnetohydrodynamic fluid within a gap and creating a seal between the container shell and the shaft. Mechanical seal devices employing MHD seals need to prevent magnetohydrodynamic leakage and contamination of the materials inside the equipment. Currently, a sealing structure is typically installed below the MHD seal structure to prevent leakage. However, even the most reliable sealing structures still carry the risk of failure and leakage. Utility Model Content
[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a magnetohydrodynamic mechanical seal device and a stirring device.
[0005] The technical solution adopted by this utility model is as follows: A magnetohydrodynamic mechanical seal device, comprising:
[0006] A bushing, used to fit onto a rotating shaft;
[0007] The outer casing is fitted onto the bushing;
[0008] The magnetic fluid sealing assembly is located between the bushing and the housing. It has a magnetic fluid sealing cavity filled with magnetic sealing fluid and an axial sealing structure at the lower end of the magnetic fluid sealing cavity.
[0009] A magnetic fluid receiving ring is disposed below the magnetic fluid sealing assembly, forming a magnetic fluid receiving cavity with a certain height between it and the outer shell, which can confine the fluid. The volume of the magnetic fluid receiving cavity is greater than the volume of the magnetic sealing liquid in the magnetic fluid sealing cavity.
[0010] The magnetic fluid receiving ring includes a limiting ring, a groove formed on the inner circumference of the outer shell below the magnetic fluid sealing assembly, and a mating ring that protrudes inward relative to the groove below the groove. The outer circumferential surface of the limiting ring fits against the inner circumferential surface of the mating ring, and there is a clearance fit between the inner circumferential surface of the limiting ring and the bushing. The upper end of the limiting ring protrudes relative to the upper end surface of the mating ring, so that it forms a magnetic fluid receiving cavity between itself and the groove to restrict the fluid.
[0011] The outer casing has a through hole at the bottom of the groove.
[0012] The magnetic fluid sealing assembly includes a magnetic guide sleeve, which is sleeved outside the sleeve and fixedly connected to it. The magnetic fluid sealing cavity and axial sealing structure are disposed between the magnetic guide sleeve and the outer shell. A certain gap is provided between the lower end of the inner circumference of the magnetic guide sleeve and the sleeve to form a slot. The upper end of the limiting ring extends into the slot and is in clearance fit with the inner circumference of the magnetic guide sleeve.
[0013] The magnetic fluid receiving ring includes a bottom connecting ring, and the limiting ring is formed by extending upward from the inner circumference of the bottom connecting ring. The bottom connecting ring is fixedly connected to the bottom of the mating ring.
[0014] A positioning pin is provided between the bottom connecting ring and the bottom of the mating ring, and the two are fastened together by bolts.
[0015] The magnetic fluid sealing assembly includes a magnetic bushing and several pole shoe assemblies. The magnetic bushing is sleeved outside the bushing and fixedly connected to it. The several pole shoe assemblies and the axial sealing structure are disposed between the magnetic bushing and the outer shell. The several pole shoe assemblies are sequentially sleeved on the outer periphery of the magnetic bushing along the axial direction and form several annular gaps with the outer peripheral surface of the magnetic bushing. The annular gaps are filled with magnetic sealing fluid.
[0016] The inner circumference of the outer shell is provided with a second support step and a third support step, the plurality of pole shoe assemblies are supported on the second support step, and the axial sealing structure is located between the pole shoe assembly and the third support step.
[0017] The axial sealing structure includes at least two second seals spaced apart along the axial direction.
[0018] A stirring device includes a rotating shaft and a container, wherein a magnetohydrodynamic mechanical seal device as described above is connected to the outside of the container, and the rotating shaft extends into the container through a bushing.
[0019] The beneficial effects of this invention are as follows: This invention provides a magnetic fluid receiving ring below the magnetic fluid sealing component within the magnetic fluid mechanical seal device, ensuring that material is not contaminated after leakage of the magnetic sealing fluid due to axial seal structure failure. This invention can be used for the shaft sealing requirements of stirring devices for materials requiring high purity, and can also be used for the sealing requirements of other devices, replacing contact-type mechanical seal devices or other non-contact mechanical seal devices. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.
[0021] Figure 1 This is a schematic diagram of the structure of the magnetohydrodynamic mechanical seal device and the rotating shaft according to an embodiment of the present invention;
[0022] Figure 2 for Figure 1 Enlarged diagram of part A in the middle;
[0023] Figure 3 for Figure 1 Enlarged diagram of section B;
[0024] In the diagram, the components are: bushing-1, second sealing isolation ring-101, outer shell-2, first support step-201, lubricating oil medium inlet / outlet-202, cooling medium inlet / outlet-203, second support step-204, third support step-205, groove-206, mating ring-207, through hole-208, cooling chamber-209, bearing assembly-3, magnetic bushing-4, slot-401, first sealing isolation ring-5, first seal-6, gland-7, retaining ring-8, pole shoe assembly-9, magnetic sealing fluid-10, second seal-11, magnetic fluid receiving ring-12, bottom connecting ring-1201, limiting ring-1202, and rotating shaft-13. Detailed Implementation
[0025] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.
[0026] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.
[0027] The directional and positional terms used in this utility model, such as up, down, front, back, left, right, inside, outside, top, bottom, side, etc., are only for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.
[0028] This utility model provides a magnetohydrodynamic mechanical seal device, such as... Figure 1 As shown, it includes a bushing 1 and a housing 2, and a bearing assembly 3 and a magnetohydrodynamic sealing assembly are connected between the bushing 1 and the housing 2.
[0029] A sealing and isolation structure is provided between the bushing 1 and the outer shell 2, dividing the space between the bushing 1 and the outer shell 2 into an upper chamber and a lower chamber. The bearing assembly 3 is disposed in the upper chamber, and the magnetohydrodynamic sealing assembly is disposed in the lower chamber. Specifically, as shown... Figure 2 As shown, the sealing and isolation structure includes a first sealing isolation ring 5, a first sealing element 6, and a second sealing isolation ring 101. The outer shell 2 has a first supporting step 201, on which the first sealing isolation ring 5 is supported. The second sealing isolation ring 101 is a convex ring integrally formed on the outer periphery of the bushing 1. The first sealing element 6 is a lip seal disposed between the first sealing isolation ring 5 and the second sealing isolation ring 101. The lower end of the inner periphery of the bearing assembly 3 is supported on the second sealing isolation ring 101 on the outer periphery of the bushing 1. A pressure cap 7 is bolted to the upper end of the outer shell 2, abutting against the upper end of the outer periphery of the bearing assembly 3. A retaining ring 8 is threadedly connected to the upper end of the bearing assembly 3 on the outer periphery of the bushing 1, forming a retaining limit on the upper end of the inner periphery of the bearing assembly 3, thus fixing the axial relative position between the bushing 1 and the outer shell 2. The outer shell 2 has a lubricating oil inlet / outlet 202 above the sealing and isolation structure for introducing lubricating oil into the bearing assembly 3.
[0030] The magnetic fluid sealing assembly includes a magnetic bushing 4, several pole shoe assemblies 9, and an axial sealing structure. The magnetic bushing 4 is sleeved outside the bushing 1 and located below the sealing isolation structure. The magnetic bushing 4 and the bushing 1 are fixedly connected by fasteners and screws. The axial sealing structure is disposed between the magnetic bushing 4 and the outer shell 2. The axial space formed between the magnetic bushing 4 and the sealing isolation structure forms a magnetic fluid sealing cavity. The several pole shoe assemblies 9 are disposed in the magnetic fluid sealing cavity. The several pole shoe assemblies 9 are sequentially sleeved on the outer periphery of the magnetic bushing 4 along the axial direction and form several annular gaps with the outer peripheral surface of the magnetic bushing 4. The annular gaps are filled with magnetic sealing liquid 10.
[0031] Specifically, such as Figure 3 As shown, the inner circumference of the outer shell 2 is provided with a second support step 204 and a third support step 205. The plurality of pole shoe assemblies 9 are axially limited between the second support step 204 and the sealing isolation structure. The second seal 11 is limited between the pole shoe assembly 9 and the third support step 205. In this embodiment, the second seal 11 is a lip seal. In order to better reduce the risk of magnetohydrodynamic leakage, in this embodiment, two second seals 11 are used, and the two second seals 11 are spaced apart along the axial direction.
[0032] In this embodiment, a magnetic fluid receiving ring 12 is provided below the magnetic fluid sealing assembly. The magnetic fluid receiving ring 12 is connected to the outer shell 2 and forms a magnetic fluid receiving cavity with a certain height between it and the outer shell 2 to restrict the fluid. The volume of the magnetic fluid receiving cavity is larger than the volume of the magnetic fluid filled in the magnetic fluid sealing cavity. With this configuration, even if both second seals 11 fail and the magnetic fluid in the magnetic fluid sealing cavity leaks downward, it will leak into the magnetic fluid receiving cavity and be restricted by the magnetic fluid receiving ring 12, preventing it from flowing into the equipment container and contaminating the material.
[0033] Specifically, the magnetic fluid receiving ring 12 includes a bottom connecting ring 1201 and a limiting ring 1202 extending upward from the inner circumference of the bottom connecting ring 1201. The inner circumference of the outer shell 2 forms a groove 206 below the magnetic fluid sealing assembly, and a mating ring 207 is formed below the groove 206 that protrudes inward relative to the groove 206. The bottom connecting ring 1201 is fixedly connected to the bottom of the mating ring 207. The outer circumferential surface of the limiting ring 1202 fits against the inner circumferential surface of the mating ring 207, and the inner circumferential surface is in clearance fit with the bushing 1. The upper end of the limiting ring 1202 protrudes relative to the upper end surface of the mating ring 207, thereby forming a magnetic fluid receiving cavity that can restrict fluid between the limiting ring 1202 and the groove 206.
[0034] Furthermore, the outer shell 2 has a through hole 208 at the bottom of the groove 206. In this embodiment, the through hole 208 is used as a purge hole to discharge magnetic fluid and clean the magnetic fluid receiving cavity when magnetic fluid leaks. A monitoring device can also be set as needed to determine whether the magnetic fluid sealing assembly is leaking by monitoring whether magnetic fluid appears in the magnetic fluid receiving cavity, so as to facilitate timely maintenance and handling.
[0035] Furthermore, a certain gap is provided between the lower end of the inner circumference of the magnetic bushing 4 and the bushing 1 to form a slot 401. The upper end of the limiting ring 1202 extends into the slot 401 and is in clearance fit with the inner circumference of the magnetic bushing 4. In this way, even if the magnetic fluid leaks between the magnetic bushing 4 and the second seal 11, the magnetic bushing 4 and the limiting ring 1202 form a double barrier.
[0036] A positioning pin is provided between the bottom connecting ring 1201 and the bottom of the mating ring 207, and the two are fastened together by bolts.
[0037] Furthermore, the outer casing 2 is provided with a cooling chamber 209 outside the magnetic fluid sealing cavity, and has a cooling medium inlet and outlet 203 connected to the cooling chamber 209. This is used to cool the magnetic fluid sealing assembly.
[0038] Furthermore, this utility model also provides a stirring device equipped with the aforementioned magnetohydrodynamic (MHD) mechanical seal, including a rotating shaft 13 and a container. The MHD mechanical seal is connected to the upper end of the container, and the rotating shaft 13 extends into the container through the bushing 1. The stirring device can be a three-in-one device for filtration, washing, and drying with vacuum function.
[0039] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.
Claims
1. A magnetohydrodynamic mechanical seal device, characterized in that, include: A bushing (1) is used to fit onto a rotating shaft (13); The outer casing (2) is fitted onto the bushing (1); The magnetic fluid sealing assembly is located between the bushing (1) and the outer shell (2), and has a magnetic fluid sealing cavity filled with magnetic sealing liquid (10) inside, and has an axial sealing structure at the lower end of the magnetic fluid sealing cavity. A magnetic fluid receiving ring (12) is disposed below the magnetic fluid sealing assembly, forming a magnetic fluid receiving cavity with a certain height between it and the outer shell, which can restrict the fluid. The volume of the magnetic fluid receiving cavity is greater than the volume of the magnetic sealing liquid (10) in the magnetic fluid sealing cavity.
2. The magnetohydrodynamic mechanical seal device according to claim 1, characterized in that: The magnetic fluid receiving ring (12) includes a limiting ring (1202), a groove (206) formed on the inner circumference of the outer shell (2) below the magnetic fluid sealing assembly, and a mating ring (207) protruding inward relative to the groove (206) below the groove (206). The outer circumferential surface of the limiting ring (1202) fits against the inner circumferential surface of the mating ring (207), and there is a clearance fit between the inner circumferential surface and the bushing (1). The upper end of the limiting ring (1202) protrudes relative to the upper end surface of the mating ring (207), so that it forms a magnetic fluid receiving cavity that can restrict the fluid between itself and the groove (206).
3. The magnetohydrodynamic mechanical seal device according to claim 2, characterized in that: The outer shell (2) has a through hole (208) at the bottom of the groove (206).
4. The magnetohydrodynamic mechanical seal device according to claim 2, characterized in that: The magnetic fluid sealing assembly includes a magnetic bushing (4), which is sleeved outside the bushing (1) and fixedly connected to the bushing (1). The magnetic fluid sealing cavity and axial sealing structure are arranged between the magnetic bushing (4) and the outer shell (2). A certain gap is provided between the lower end of the inner circumference of the magnetic bushing (4) and the bushing (1) to form a slot (401). The upper end of the limiting ring (1202) extends into the slot (401) and is in clearance fit with the inner circumference of the magnetic bushing (4).
5. The magnetohydrodynamic mechanical seal device according to claim 2, characterized in that: The magnetic fluid receiving ring (12) includes a bottom connecting ring (1201), and the limiting ring (1202) is formed by extending upward from the inner circumference of the bottom connecting ring (1201). The bottom connecting ring (1201) is fixedly connected to the bottom of the mating ring (207).
6. The magnetohydrodynamic mechanical seal device according to claim 5, characterized in that: The bottom connecting ring (1201) and the mating ring (207) are provided with a positioning pin and are fastened together by bolts.
7. The magnetohydrodynamic mechanical seal device according to claim 1, characterized in that: The magnetic fluid sealing assembly includes a magnetic bushing (4) and several pole shoe assemblies (9). The magnetic bushing (4) is sleeved outside the bushing (1) and fixedly connected to the bushing (1). The several pole shoe assemblies (9) and the axial sealing structure are arranged between the magnetic bushing (4) and the outer shell (2). The several pole shoe assemblies (9) are sequentially sleeved on the outer periphery of the magnetic bushing (4) along the axial direction and form several annular gaps with the outer peripheral surface of the magnetic bushing (4). The annular gaps are filled with magnetic sealing liquid (10).
8. The magnetohydrodynamic mechanical seal device according to claim 7, characterized in that: The inner circumference of the outer shell (2) is provided with a second support step (204) and a third support step (205), the plurality of pole shoe assemblies (9) are supported on the second support step (204), and the axial sealing structure is located between the pole shoe assembly (9) and the third support step (205).
9. The magnetohydrodynamic mechanical seal device according to claim 7, characterized in that: The axial sealing structure includes at least two second seals (11) spaced apart along the axial direction.
10. A stirring device, comprising a rotating shaft (13) and a container, characterized in that: The container is externally connected to a magnetohydrodynamic mechanical seal device as described in any one of claims 1-9, and the rotating shaft (13) extends into the container through the bushing (1).