A tool for assembling large-diameter magnetic liquid seals

Abstract

The present invention provides a tool for assembling large-diameter magnetic liquid seals, comprising a positioning shaft and a positioning sleeve. The positioning shaft is designed with a through hole for connection with the sealing main shaft, and a stop is designed to ensure coaxiality with the sealing main shaft. The positioning sleeve is designed with a through hole for connection with the sealing shell, and a stop is designed to ensure coaxiality with the sealing shell; a threaded hole is designed above the positioning sleeve. The invention ensures the coaxiality of the sealing main shaft and the sealing shell during installation by positioning the mating surfaces of the positioning shaft and the positioning sleeve, and adjusts the height of the pole shoe shaft by screws. The tool can ensure that when assembling the magnetic liquid seal, the pole shoe will not scratch the rotating shaft due to excessive magnetic force, thereby effectively avoiding the pole tooth damage that is easily caused during the installation of existing magnetic liquid seals, protecting the seal and other parts, effectively improving work efficiency, and preventing dangerous operations.

Description

Technical Field

[0001] The patent of this invention relates to the field of tooling technology, and in particular to a tooling for assembling magnetic liquid seals. Technical Background

[0002] Magnetic fluid seals are a new type of sealing method with advantages such as zero leakage, long life, and high reliability. They are widely used in aviation, aerospace, vacuum, and chemical industries. As shown in Patent No. 201810364032.8, magnetic fluid seal assemblies typically consist of two pole pieces, a permanent magnet, and a magnetic shaft. Magnetic fluid is injected into the sealing gap between the pole pieces and the shaft. The magnetic fluid is magnetically attracted to the pole teeth, forming a series of liquid rings similar to "O" rings, which act as a seal.

[0003] The pole pieces and shafts of magnetic fluid seals are constructed from highly permeable materials such as electrical pure iron and 2Cr13. The magnetic source is typically a strong permanent magnet such as neodymium iron boron. During assembly, the magnetic field is very strong, making collisions very likely. Furthermore, the sealing gap is small, the pole teeth are thin, and the magnetic force is high. Without tooling, the pole teeth can be easily damaged during assembly or disassembly, directly impacting sealing performance and reliability. Furthermore, without tooling, assembly is performed manually by the operator, which can be dangerous. Therefore, when using large-diameter magnetic fluid seals, especially when they require frequent assembly and disassembly, a tooling system for large-diameter magnetic fluid seals is necessary. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a tool for assembling a large-diameter magnetic liquid seal, which can solve the problem that the pole teeth are easily damaged when the large-diameter magnetic liquid seal is installed.

[0005] The present invention solves the technical problem by employing a technical solution comprising: a tool for assembling a large-diameter magnetic liquid seal, comprising a locating sleeve and a locating shaft. The locating sleeve should be made of a non-magnetic material with good mechanical properties and connected to the magnetic liquid seal housing via a through hole or a threaded hole. The locating sleeve is designed to connect to the magnetic liquid seal housing through a through hole and a threaded hole for connecting to an eyebolt, facilitating installation when the seal is too heavy. The locating shaft should be made of a non-magnetic material with good mechanical properties and connected to the magnetic liquid seal main shaft via a through hole or a threaded hole.

[0006] Furthermore, the inner diameter surface of the positioning sleeve and the outer diameter surface of the positioning shaft are designed to fit with a small gap to ensure the coaxiality during the assembly of the magnetic liquid seal. The maximum gap should be smaller than the sealing gap, and the axial length of the fitting surface should be greater than the axial length of the sealing assembly and the sealing main shaft, thereby preventing damage to the pole teeth during assembly.

[0007] Furthermore, the positioning sleeve is designed with a threaded hole, which is matched with a long screw to adjust the distance between the positioning sleeve and the positioning shaft, so that the magnetic liquid seal can be slowly installed in place during the installation process.

[0008] Furthermore, the positioning sleeve is designed with a through hole connected to the magnetic liquid sealing shell; and a threaded hole is designed to be connected to the eye bolt to facilitate installation when the seal is too heavy.

[0009] The beneficial effects achieved by the present invention are as follows: a tool for assembling a large-diameter magnetic liquid seal is provided. When in use, the sealing main shaft is first installed on the shaft system, and then the positioning shaft is installed. The position of the positioning shaft is adjusted so that the outer diameter of the positioning shaft is as coaxial as possible with the sealing main shaft. The sealing shell is then connected to the positioning sleeve, installed in the upper threaded hole, and the long screw is installed. The whole is inserted into the positioning shaft, moved downward evenly and slowly, and finally lowered to the installation position. After removing the tool and tightening the screws, the magnetic liquid seal assembly is completed. When assembling with the above-mentioned tool, there is no need to specially design or modify the magnetic liquid seal structure and the shaft system structure. The use of the modified tool can effectively avoid the influence of magnetic field force during assembly, thereby preventing damage to the magnetic liquid seal structure, improving the sealing reliability, and ensuring the safety of manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a front view of the structure of the present invention

[0011] Figure 2 It is a schematic diagram of the positioning sleeve 1 of the present invention being connected to the sealing housing 4 , the magnetic liquid sealing assembly 5 , and the sealing end cover 6 by screws 10 .

[0012] Figure 3 It is a schematic diagram of the present invention after the positioning shaft 2 and the sealing main shaft 7 are connected by screws 11.

[0013] Figure 4 The present invention is a schematic diagram of a magnetic liquid seal after being installed in place.

[0014] The serial numbers in the figure and the corresponding structure names are as follows: 1- positioning sleeve, 2- positioning shaft, 3- lifting eye bolt, 4- sealing housing, 5- sealing assembly, 6- sealing end cover, 7- sealing spindle, 8- rotating base, 9- fixed base, 10- screw, 11- screw, 12- long screw, 13- top screw, 101- positioning sleeve inner diameter surface, 102- first threaded hole, 103- first through hole, 104- second threaded hole, 105- first stop, 201- positioning shaft outer diameter surface, 202- countersunk screw hole, 203- second through hole, 204- third through hole, 205- second stop. DETAILED DESCRIPTION

[0015] During seal installation, the sealing spindle 7 is mounted on the rotating base 8. After adjusting the radial runout of the sealing spindle, tighten the screws to secure it. After adjusting the coaxiality of the positioning shaft 2 and the sealing spindle 7, connect the positioning shaft 2 and the sealing spindle 7 with screws 11. After installing the magnetic liquid sealing assembly 5 into the sealing housing 4, install the sealing end cover 6. The assembled sealing housing 4 is connected to the positioning sleeve 1 using screws 10, and the coaxiality of the positioning sleeve 1 and the sealing housing 4 is ensured by the fit of the stopper. The top screw 13 is installed in the countersunk screw hole 202, and the screw is installed in the corresponding first threaded hole 102. After the inner diameter of the magnetic liquid sealing assembly 5 is evenly coated with magnetic liquid, the positioning sleeve 1 is inserted into the positioning shaft 2 from top to bottom. The small gap between the inner diameter surface 101 and the outer diameter surface 201 ensures the coaxiality of the magnetic liquid sealing assembly 5 and the sealing spindle 7 during assembly, thereby preventing scratches between the parts. To reduce friction between the locating sleeve 1 and the locating shaft 2, apply a small amount of lubricating oil or grease to the locating sleeve's inner diameter surface 101 and outer diameter surface 201. Adjusting the screw height ensures that the locating sleeve 1 descends slowly under the influence of a strong magnetic field, effectively avoiding dangerous operations during seal installation. Once the seal is in place, remove the locating sleeve 1 first, then the locating shaft 2. Connect the seal housing 4 to the fixed base 9 with screws to complete the seal assembly.

[0016] When disassembling the seal, first install the positioning shaft 2 in place with the screw 11, and adjust the radial runout to make it as coaxial as possible with the sealing main shaft 7. Remove the fixing screws of the sealing shell 4 and the fixed base 9, insert the positioning sleeve 1 into the positioning shaft 2, and connect it to the sealing shell 4 with the screw 10. Install the top screw in the countersunk screw hole 202, and install the screw in the corresponding first threaded hole 102. By adjusting the height of the screw, the positioning sleeve 1 and the sealing shell 4 move upward slowly and evenly. After the magnetic liquid sealing assembly 5 is completely moved out of the sealing main shaft 7, the magnetic field force is significantly reduced, and the positioning sleeve 1 is taken out. Remove the connecting screws 10 and screws 11, wipe off the magnetic liquid on the magnetic liquid sealing assembly 5 and the sealing main shaft 7, and complete the seal disassembly.

[0017] The beneficial effect of the present invention is that, when the present invention is used for installation, the magnetic liquid sealing assembly 5 and the sealing main shaft 5 can be effectively protected to prevent scratches from occurring and damage to the sealing structure; when assembling and disassembling the seal, the operating actions are all on the tooling, which can prevent damage to the operator and other sealing parts due to improper operation during assembly and disassembly.

Claims

1. A tool for assembling a large-diameter magnetic liquid seal, comprising a positioning sleeve (1) and a positioning shaft (2), characterized in that: The inner diameter of the positioning sleeve (1) is the positioning sleeve inner diameter surface (101), the positioning sleeve (1) is provided with at least 4 first threaded holes (102), the positioning sleeve (1) is provided with a first through hole (103) matched with the sealing shell (4), and the positioning sleeve (1) is provided with a second threaded hole (104) used in conjunction with the eye bolt (3); the outer diameter of the positioning shaft (2) is the positioning shaft outer diameter surface (201), the positioning shaft (2) is provided with a countersunk screw hole (202) corresponding to the first threaded hole (102), the positioning shaft (2) is provided with a second through hole (203) matched with the sealing main shaft, and the positioning shaft (2) is provided with a third threaded hole (104) matched with the second threaded hole (104). Through hole (204); the inner diameter surface (101) of the positioning sleeve and the outer diameter surface (201) of the positioning shaft should be designed to have the same diameter and be designed to be clearance-matched, and the maximum clearance should be smaller than the sealing clearance of the magnetic liquid seal; the axial length of the inner diameter surface (101) of the positioning sleeve and the outer diameter surface (201) of the positioning shaft should be greater than the axial length of the sealing assembly (5) and the sealing main shaft (7); the positioning sleeve (1) is designed with a first stop (105) that matches the sealing housing (4); the positioning shaft (2) is designed with a second stop (205) that matches the sealing main shaft (7).

2. The tooling for assembling a large-diameter magnetic liquid seal according to claim 1, characterized in that: The first threaded holes (102) correspond to the countersunk screw holes (202), and the number thereof is at least four.

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