Double-shaft transmission magnetic fluid sealing structure

Abstract

The utility model relates to the technical field of magnetic fluid sealing, in particular to a double-shaft transmission magnetic fluid sealing structure. The structure comprises a structure body, the structure body comprises a shell, a center shaft is arranged in the shell, an intermediate shaft is arranged on the outer side of the center shaft, a first magnet is arranged between the center shaft and the intermediate shaft, a second magnet is arranged between the intermediate shaft and the shell, a middle bearing is arranged on the inner side of the center shaft in a sleeved mode, and two first magnetic poles are installed on the two sides of the first magnet. A second rear bearing and a third screw cover plate are sequentially installed behind the other side of the middle bearing, the front side of the intermediate shaft is sleeved with a second front bearing, second magnetic poles are arranged on the two sides of the second magnet on the outer side of the intermediate shaft respectively, and a first rear bearing is arranged on the rear side of a second shaft clamp at the rear end. According to the utility model, multi-layer coaxial simultaneous rotation can be realized, the rotation of the central shaft and the rotation of the intermediate shafts do not influence each other, and the stability and the leakage rate are not reduced; and two independent vacuum environments are formed between the central shaft and the intermediate shaft and between the intermediate shaft and the shell.

Description

TECHNICAL FIELD

[0001] The utility model relates to magnetic fluid sealing technical field, concretely relates to a kind of magnetic fluid sealing structure of double-shaft transmission. BACKGROUND

[0002] In recent years, domestic and foreign vacuum equipment develops rapidly.In many rotary sealing devices, magnetic fluid sealing has been widely used, for example, in the sealing of single crystal silicon furnace, vacuum brazing furnace, vacuum smelting furnace, chemical vapor deposition, ion plating, liquid crystal regeneration and other vacuum equipment, as well as high temperature and high pressure equipment and equipment with high environmental requirements, thereby improving product quality and achieving good economic benefits.

[0003] Magnetic fluid sealing technology is developed on the basis of magnetic fluid, which can fill the entire gap when magnetic fluid is injected into the gap of magnetic field, forming a kind of "liquid O-shaped sealing ring".The function of magnetic fluid sealing device is to transmit rotary motion to the sealed container, which is commonly used for vacuum sealing.

[0004] At present, in the process of applying magnetic fluid technology, the contact between the outer surface of the magnetically conductive shaft or magnetically conductive sleeve and the inner surface of the sealing assembly causes sealing failure. This phenomenon is more likely to occur in structures without bearings in the magnetic flow sealing element; this is generally due to the fact that during the installation of the magnetic fluid sealing element, the coaxiality of the rotating shaft and the sealing assembly is not found, causing eccentricity, contact, short circuit of the magnetic force line of the sealing gap, damage to the magnetic flow liquid film, and thus causing leakage; and in recent years, the birth of various vacuum equipment has different needs, and under the condition of constant vacuum leakage rate, connecting multiple vacuum cavities at the same axis is one of them, therefore we urgently need to design a hollow shaft magnetic fluid sealing structure to solve the above problems. UTILITY MODEL CONTENTS

[0005] The utility model aims at the defects and deficiencies of prior art, and provides a kind of double-shaft transmission's magnetic fluid sealing structure with reasonable design, which can solve the above defects.

[0006] In order to achieve the above object, the utility model adopts the following technical scheme: it contains structure ontology, the structure ontology includes the casing, the inside of casing is provided with the central shaft, the outside of central shaft is equipped with the interval shaft, is equipped with magnetism one between central shaft and interval shaft, is equipped with magnetism two between interval shaft and casing, the inside of central shaft is equipped with the middle bearing, the both sides of middle bearing are equipped with the shaft card one, installs two magnetic ring one on the central shaft of one side of shaft card one, magnetism one is located between two magnetic ring one, installs two magnetic pole one on the both sides of magnetism one, installs the front bearing one and screw cover plate one on the front side of magnetic ring one, the other side of middle bearing is the installation step of shaft card, installs the rear bearing two, screw cover plate three in proper order after step, the front side of interval shaft is equipped with the front bearing two, the one side of front bearing two is interval shaft positioning step, the other side is positioned by the inside of magnetic guide sleeve and shaft card two, is equipped with magnetic pole two on the both sides of magnetism two outside the interval shaft, is equipped with magnetic ring two outside magnetic pole two, is equipped with the rear bearing one on the rear side of rear end shaft card two, and is locked through screw cover plate two.

[0007] Preferably, the casing is provided with a flange counterbore, which is arranged on the outside of the casing.

[0008] Preferably, the central shaft is provided with key groove one and key groove two on both sides, and a milling groove on the rear side.

[0009] Preferably, the magnetism one and magnetism two are one of a button-like structure or a ring-like structure.

[0010] Preferably, the outside of the magnetic pole one and the magnetic pole two is respectively provided with a group of magnetic pole sealing groove one and magnetic pole sealing groove two.

[0011] Preferably, the central shaft is rotationally sealed relative to the interval shaft, the interval shaft is rotationally sealed relative to the outer shell, and the interval shaft is made of non-magnetic stainless steel material, thereby being provided with a magnetic guide sleeve to form a sealed magnetic field with the magnetic guide sleeve, the magnetic pole two and the magnetism two, and compensate for the non-magnetic property of the interval shaft.

[0012] After adopting the above structure, the utility model has the beneficial effects that:

[0013] 1. The utility model can realize the simultaneous rotation of multiple coaxial layers, the rotation between the central shaft and the interval shaft does not affect each other, and does not reduce the stability and leakage rate; two independent vacuum environments are formed between the central shaft and the interval shaft, and between the interval shaft and the casing.

[0014] 2. The utility model adopts non-magnetic stainless steel material for the interval shaft, thereby forming an incomplete magnetic field with the magnetic pole two and the magnetism two, and thus adding a magnetic guide sleeve made of magnetic material to make the magnetic field loop complete. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a structural schematic view of the utility model.

[0016] Mark explanation:

[0017] 1, keyway one; 2, threaded hole one; 3, front bearing one; 4, magnetic liquid tank; 5, magnetic pole sealing groove one; 6, magnet one; 7, flange counterbore; 8, front bearing two; 9, shaft clamp one; 10, middle bearing; 11, interval shaft sealing groove; 12, magnet two; 13, magnet conducting shaft sleeve magnetic liquid tank; 14, magnetic pole sealing groove two; 15, shaft clamp two; 16, rear bearing one; 17, rear bearing two; 18, internal hexagonal screw; 19, keyway two; 20, milling groove; 21, threaded hole two; 101, center shaft; 102, threaded cover plate one; 103, interval shaft; 104, magnetic separation ring one; 105, magnetic pole one; 106, shell; 107, magnetic separation ring two; 108, magnetic pole two; 109, magnet conducting shaft sleeve; 110, threaded cover plate two; 111, screw cover plate three. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.

[0019] Reference Figure 1As shown, it comprises a structural body, the structural body includes a shell 106, the front end of the shell 106 is connected with a vacuum device, the shell 106 is made of non-magnetic stainless steel material, the inside of the shell 106 is provided with a center shaft 101, the outside of the center shaft 101 is provided with an interval shaft 103, the center shaft 101 and the interval shaft 103 are provided with a magnet one 6, the interval shaft 103 and the shell 106 are provided with a magnet two 12, the inside of the center shaft 101 is sleeved with a middle bearing 10, both sides of the middle bearing 10 are sleeved with a shaft clamp one 9, two magnetic separation rings one 104 are installed on the center shaft 101 at one side of the shaft clamp one 9, the magnet one 6 is arranged between the two magnetic separation rings one 104, two magnetic poles one 105 are installed on both sides of the magnet one 6, the front bearing one 3 and the threaded cover plate one 102 are installed on the front side of the magnetic separation ring one 104, the shaft clamp on the other side of the middle bearing 10 is a mounting step, the rear bearing two 17 and the screw cover plate three 111 are installed in turn after the step, the front bearing two 8 is sleeved with the front bearing two 8, one side of the front bearing two 8 is an interval shaft positioning step, the other side is positioned by the inside magnetic shaft sleeve 109 and the shaft clamp two 15, the magnetic pole two 108 is arranged on the outside of the magnet two 12 on both sides of the interval shaft 103, the magnetic separation ring two 107 is installed on the outside of the magnetic pole two 108, the rear side of the shaft clamp two 15 at the rear end is provided with the rear bearing one 16 and is locked through the threaded cover plate two 110; two pairs of magnetic separation rings are arranged on both sides of the two magnetic poles one 105 and the magnetic pole two 108 respectively, which are used to cut off the magnetic field loop to prevent the magnetic field from being close to the bearing and affecting the rotation of the bearing;

[0020] The flange counterbore 7 is arranged on the shell 106, which is arranged on the outside of the shell 106 to facilitate the connection between the shell 106 and the vacuum device;

[0021] The center shaft 101 is installed in the interval shaft 103, one side of both ends is provided with a key groove one 1 to connect the vacuum device; the other side is provided with a key groove two 19 and a milling groove 20 to connect the power device, the interval shaft 103 is provided with a threaded hole one 2 and a threaded hole two 21, the interval shaft 103 is connected to the transmission device and the vacuum device through the threaded hole one 2 and the threaded hole two 21, the material of the interval shaft 103 is non-magnetic stainless steel, so that the magnetic field formed by the magnetic pole one 105 and the magnet one 6 is separated by the interval shaft 103, and the magnetic field formed by the magnetic pole two 108 and the magnet two 12 is also separated by the interval shaft 103, the two magnetic fields do not interfere with each other due to the interval shaft 103;

[0022] The magnet one 6 and the magnet two 12 are one of a button-like structure or a ring-like structure;

[0023] The outside of the magnetic pole one 105 and the magnetic pole two 108 is respectively provided with a group of magnetic pole sealing grooves one 5 and magnetic pole sealing grooves two 14;

[0024] The central shaft 101 is rotationally sealed relative to the intermediate shaft 103, and the intermediate shaft 103 is rotationally sealed relative to the housing. The intermediate shaft 103 is made of non-magnetic stainless steel material, and a magnetic shaft sleeve 109 is provided, which is made of magnetic material, so that the magnetic shaft sleeve 109, the magnetic pole two 108 and the magnet two 12 form a sealed magnetic field to compensate for the non-magnetic property of the intermediate shaft 103. The intermediate shaft 103 at the inner side of the magnetic shaft sleeve 109 is provided with an intermediate shaft sealing groove 11, and after the sealing ring is added, the intermediate shaft 103 and the magnetic shaft sleeve 109 are sealed. The intermediate shaft 103 and the magnetic shaft sleeve 109 are in high-precision transition fit to ensure the necessary rotation accuracy. One side of the magnetic shaft sleeve 109 is the front bearing two 8, and the other side of the front bearing two 8 is the positioning step. The other side of the magnetic shaft sleeve 109 is the shaft clamp two 15, so that the magnetic shaft sleeve 109 and the front bearing two 8 are positioned on the intermediate shaft 103.

[0025] The magnetic pole one 105 and the magnetic pole two 108 have the same function. The magnetic pole two 108 is made of 3cr13 or 2cr13 magnetic material, and the magnet two 12 is a permanent magnet. The shaft part at the inner side of the magnet two 12 is provided with a magnetic liquid groove 4. The magnetic shaft sleeve 109 is added to replace the original magnetic shaft because the intermediate shaft 103 is made of non-magnetic material. The magnetic liquid groove 4 is provided on the magnetic shaft sleeve 109, and magnetic liquid is added in the magnetic liquid groove 4. In this way, a magnetic field loop is formed between the magnetic pole two 108, the magnet two 12, the intermediate shaft 103 and the magnetic liquid, which is a kind of liquid seal and the main sealing part of the magnetic fluid. A certain gap is left between the magnetic pole two 108 and the intermediate shaft 103, and the magnetic pole two 108 and the intermediate shaft 103 are supported by the front bearing two 8 and the rear bearing one 16 on both sides to ensure that the magnetic pole two 108 does not contact the shaft during operation, so as to affect the magnetic fluid seal. The magnetic pole two 108 is provided with a magnetic pole sealing groove two 14 on the outer side, and a sealing ring is added in the sealing groove for static sealing between the magnetic pole two 108 and the housing. It should be noted that the compression resistance of the sealing ring is selected according to the pressure difference between the vacuum equipment and the atmosphere to ensure the sealing of the magnetic fluid.

[0026] When working, one motor drives the transmission device to rotate on the key groove two 19 on the one side of the center shaft 101, and the other key groove one 1 drives the vacuum equipment internal device connected with the shaft to rotate, at the same time, the magnetic fluid on the magnetic pole one 105, the magnet one 6 and the magnetic liquid groove 4 forms a magnetic field loop to make the magnetic liquid pressure stable; the other route is driven by another motor to drive the transmission device from the threaded hole two 21 to the screw cover plate three 111, the screw cover plate three 111 is fixed on the intermediate shaft 103 by the internal hexagonal screw 18, so that the transmission is linked, after the transmission, the intermediate shaft 103 outputs at the threaded hole one 2 connected with another vacuum equipment, so that the transmission is formed, similarly, the magnetic fluid in the magnetic liquid groove 13 on the magnetic pole two 108, the magnet two 12 and the magnetic guide shaft sleeve 109 forms a magnetic field loop to make the magnetic liquid pressure stable, the center shaft 101 transmission and the intermediate shaft 103 transmission can reach different rotating speeds to meet the needs of the vacuum equipment.

[0027] It should be understood that the above specific embodiments of the present application are only used for illustrative or explanatory purposes of the principles of the present application, and do not constitute a limitation of the present application. Therefore, any modification, equivalent replacement, improvement, etc. made without departing from the spirit and scope of the present application shall be included in the protection scope of the present application. In addition, the appended claims of the present application are intended to cover all changes and modifications falling within the scope and boundary of the appended claims, or the equivalent forms of such scope and boundary.

Claims

1. A magnetic fluid seal structure of double shaft transmission comprising a structural body, characterized in that: The structure body includes a shell (106), the inside of the shell (106) is provided with a center shaft (101), the outside of the center shaft (101) is provided with an interval shaft (103), a magnet one (6) is arranged between the center shaft (101) and the interval shaft (103), a magnet two (12) is arranged between the interval shaft (103) and the shell (106), the inside of the center shaft (101) is sleeved with a middle bearing (10), the two sides of the middle bearing (10) are sleeved with a shaft clamp one (9), the center shaft (101) at one side of the shaft clamp one (9) is provided with two magnetic shielding rings one (104), the magnet one (6) is arranged between the two magnetic shielding rings one (104), two magnetic poles one (105) are arranged on the two sides of the magnet one (6), a front bearing one (3) and a threaded cover plate one (102) are arranged on the front side of the magnetic shielding ring one (104), the shaft clamp on the other side of the middle bearing (10) is a mounting step, a rear bearing two (17) and a screw cover plate three (111) are sequentially arranged after the step, the front side of the interval shaft (103) is sleeved with a front bearing two (8), one side of the front bearing two (8) is an interval shaft positioning step, the other side is positioned by an inner magnetic shaft sleeve (109) and a shaft clamp two (15), the outside of the magnet two (12) on the outside of the interval shaft (103) is respectively provided with a magnetic pole two (108), the outside of the magnetic pole two (108) is respectively provided with a magnetic shielding ring two (107), the rear side of the shaft clamp two (15) at the rear end is provided with a rear bearing one (16), and is locked by a threaded cover plate two (110).

2. A dual shaft transmission magneto-fluid seal structure according to claim 1, wherein: The shell (106) is provided with a flange counterbore (7), and the flange counterbore (7) is arranged on the outside of the shell (106).

3. A dual shaft transmission magneto-fluid seal structure according to claim 2, wherein: The center shaft (101) is respectively provided with a key groove one (1) and a key groove two (19) on the two sides, and is provided with a milling groove (20) on the rear side, the interval shaft (103) is provided with a threaded hole one (2) and a threaded hole two (21) on the two sides.

4. A dual shaft transmission magneto-fluid seal structure according to claim 3, wherein: The magnet one (6) and the magnet two (12) are one of a button structure or a ring structure.

5. A dual shaft transmission magneto-fluid seal structure according to claim 4, wherein: The outside of the magnetic pole one (105) and the magnetic pole two (108) is respectively provided with a group of magnetic pole sealing grooves one (5) and magnetic pole sealing grooves two (14).

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