Two-stage magnetofluid sealing device with nitrogen protection

Abstract

The utility model discloses a two-stage magnetofluid sealing device with nitrogen protection, which belongs to the technical field of magnetofluid sealing and comprises a shell, two bearings are fixedly sleeved in an inner cavity of the shell, a transmission shaft is sleeved on the inner sides of the two bearings, two magnetofluid sealing elements are sleeved in the inner cavity of the shell, and the two magnetofluid sealing elements are sleeved on the inner cavity of the shell. The inner side faces of the two magnetofluid sealing pieces are attached to the outer side face of the transmission shaft. According to the utility model, the spaces between the dustproof oil seal ring and the bearing, between the bearing and the magnetofluid sealing elements and between the magnetofluid sealing elements are filled with nitrogen, so that the dustproof oil seal ring, the bearing and the magnetofluid sealing elements are protected by the nitrogen; the corrosion of water vapor in the air to the dustproof oil seal ring, the bearing and the magnetofluid sealing element is avoided, and the oxidation of oxygen in the air to a magnetic material in the magnetofluid sealing element can also be avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to magnetic fluid sealing technical field more specifically, relate to a kind of two-stage magnetic fluid sealing device with nitrogen protection. BACKGROUND

[0002] Magnetic fluid sealing technology is developed on the basis of magnetic fluid, when magnetic fluid is injected into the gap of magnetic field, it can fill the entire gap, form a kind of "liquid O type sealing ring", widely used in vacuum system, rotating machinery, medical equipment, semiconductor manufacturing and aerospace military fields.

[0003] Through retrieval, the utility model patent with publication No. CN222416020U discloses a kind of two-stage magnetic fluid sealing device with nitrogen protection, including bipolar nitrogen protection mechanism, bipolar nitrogen protection mechanism includes shell, the outside of shell is fixedly connected with nitrogen inlet by flange, the inside of shell is fixedly installed with first magnetic fluid seal and second magnetic fluid seal;The patent is set through the setting of bipolar nitrogen protection mechanism, through the setting of bipolar nitrogen protection mechanism, the magnetic fluid sealing device of this patent adopts two-stage magnetic fluid sealing structure, the front end of first magnetic fluid seal is close to cavity one side, second magnetic fluid seal is set at the other side position, shell flange is equipped with nitrogen inlet, compared with the single-stage magnetic fluid sealing of the past, in the case where first magnetic fluid seal fails, the magnetic fluid sealing device second magnetic fluid seal of this structure can still continue to play the sealing effect of equivalent effect;The service life of magnetic fluid sealing is prolonged.The above-mentioned patent still has the following deficiencies:although effective sealing can be carried out through bipolar magnetic fluid seal, there can be air in the space where magnetic fluid seal is located, and air can oxidize magnetic material, affect its service life and sealing effect.For this reason, we propose a kind of two-stage magnetic fluid sealing device with nitrogen protection. UTILITY MODEL CONTENT

[0004] In view of the problems existing in the prior art, the utility model aims at providing a two-stage magnetic fluid sealing device with nitrogen protection.

[0005] To solve the above problems, the utility model adopts the following technical scheme: a two-stage magnetic fluid sealing device with nitrogen protection, including shell, the inner cavity of shell is fixedly sleeved with two bearings, the inner side of two bearings is sleeved with transmission shaft, the inner cavity of shell is sleeved with two magnetic fluid seals, the inner side surface of two magnetic fluid seals and the outer side surface of transmission shaft are attached, the both ends of shell inner cavity are sleeved with dust-proof oil seal ring, the both ends of shell are installed with cover, the top of shell is provided with multiple gas injection ports, the top end of multiple gas injection ports is fixedly installed with first switch valve, the bottom of shell is provided with multiple exhaust ports, the bottom end of multiple exhaust ports is fixedly installed with second switch valve.

[0006] As a preferred scheme of the utility model, two ends of the shell are respectively provided with mounting grooves, inner walls of the two mounting grooves are respectively provided with a plurality of screw holes, the cover is sleeved in the inner cavity of the mounting groove, a plurality of bolts are sleeved on the cover, end portions of the plurality of bolts are threadedly installed into the inner cavities of the screw holes.

[0007] As a preferred scheme of the utility model, both ends of the inner cavity of the shell are provided with clamping grooves, the dustproof oil seal ring is sleeved in the inner cavities of the clamping grooves, the inner side surface of the dustproof oil seal ring and the side surface of the transmission shaft are attached, the inner wall of the clamping groove and the outer side surface of the dustproof oil seal ring are attached, and the inner end surface of the cover and the end surface of the dustproof oil seal ring are attached.

[0008] As a preferred scheme of the utility model, both ends of the shell are provided with connecting flanges, a plurality of mounting holes are formed in the connecting flanges.

[0009] As a preferred scheme of the utility model, the middle part of the cover is provided with a perforation, and the transmission shaft penetrates the inner cavity of the perforation.

[0010] As a preferred scheme of the utility model, the inner wall of the mounting groove and the side surface of the cover are attached, and the outer end surface of the cover and the end surface of the shell are flush.

[0011] Compared with the prior art, the utility model has the advantages that in the utility model, the space among the dustproof oil seal ring, the bearing and the magnetic fluid sealing piece in the inner cavity of the shell is filled with nitrogen, the dustproof oil seal ring, the bearing and the magnetic fluid sealing piece are protected by nitrogen, corrosion of water vapor in the air on the dustproof oil seal ring, the bearing and the magnetic fluid sealing piece is avoided, and oxidation of the magnetic material in the magnetic fluid sealing piece by oxygen in the air is also avoided. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is the whole structure schematic diagram of the utility model;

[0013] Figure 2 It is the whole sectional view schematic diagram of the utility model;

[0014] Figure 3 It is the structure schematic diagram of the shell of the utility model;

[0015] Figure 4 It is the structure schematic diagram of the cover of the utility model.

[0016] Label explanation: 1, shell; 2, transmission shaft; 3, dustproof oil seal ring; 4, cover; 5, bearing; 6, magnetic fluid seal; 7, gas injection port; 8, first switch valve; 9, exhaust port; 10, second switch valve; 11, clamping groove; 12, mounting groove; 13, screw hole; 14, bolt; 15, perforation; 16, connecting flange; 17, mounting hole. DETAILED DESCRIPTION

[0017] 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.

[0018] In the description of the utility model, it should be explained that the terms 'upper', 'lower', 'inner', 'outer', 'top / bottom end' and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms 'first' and'second' are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0019] In the description of the utility model, it should be explained that, unless otherwise explicitly specified and limited, the terms'mounting', 'provided with','sleeved / connected', 'connected' and the like should be understood broadly, for example, 'connected' can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances. Embodiment 1

[0020] Please refer to Figures 1-4 A two-stage magnetic fluid sealing device with nitrogen protection, comprising a shell 1, the inner cavity of the shell 1 is fixedly sleeved with two bearings 5, the inner side of the two bearings 5 is sleeved with a transmission shaft 2, the inner cavity of the shell 1 is sleeved with two magnetic fluid sealing elements 6, the inner side surface of the two magnetic fluid sealing elements 6 and the outer side surface of the transmission shaft 2 are in close contact, the inner cavity of the shell 1 is sleeved with a dustproof oil seal ring 3 at both ends, the shell 1 is provided with a cover 4 at both ends, the top of the shell 1 is provided with a plurality of gas injection ports 7, the top end of the plurality of gas injection ports 7 is fixedly provided with a first switch valve 8, the bottom of the shell 1 is provided with a plurality of exhaust ports 9, and the bottom end of the plurality of exhaust ports 9 is fixedly provided with a second switch valve 10.

[0021] In the embodiment, the bottom end of the inner cavity of the plurality of gas injection ports 7 and the top end of the inner cavity of the plurality of gas exhaust ports 9 are respectively connected with the dustproof oil seal ring 3 and the bearing 5, the bearing 5 and the magnetic fluid seal 6, the space between the magnetic fluid seal 6 and the magnetic fluid seal 6, and the top end of the plurality of first switch valves 8 can be connected with the external nitrogen input pipe, so as to guide the nitrogen into the space between the dustproof oil seal ring 3 and the bearing 5, the bearing 5 and the magnetic fluid seal 6, and the magnetic fluid seal 6 and the magnetic fluid seal 6 in the inner cavity of the shell 1, and the magnetic fluid seal 6 is composed of a permanent magnet, a pole shoe and a magnetic fluid, the permanent magnet is installed on the inner side wall of the shell 1, the pole shoes are respectively arranged on the left and right sides of the permanent magnet, the magnetic liquid groove is arranged on the outer side wall close to the pole shoe of the transmission shaft 2, and the magnetic fluid is arranged on the magnetic liquid groove.

[0022] Specifically, please refer to Figures 1 to 4 Two installation grooves 12 are respectively arranged at the two ends of the shell 1, a plurality of screw holes 13 are arranged in the inner walls of the two installation grooves 12, the cover 4 is sleeved in the inner cavity of the installation groove 12, a plurality of bolts 14 are sleeved on the cover 4, and the end portions of the plurality of bolts 14 are threadedly installed into the inner cavities of the screw holes 13.

[0023] In the embodiment, the cover 4 is installed in the inner cavity of the installation groove 12 through the cooperation of the screw holes 13 and the bolts 14.

[0024] Specifically, please refer to Figure 2 and Figure 3 The clamping grooves 11 are arranged at the two ends of the inner cavity of the shell 1, the dustproof oil seal ring 3 is sleeved in the inner cavity of the clamping groove 11, the inner side surface of the dustproof oil seal ring 3 is attached to the side surface of the transmission shaft 2, the inner wall of the clamping groove 11 is attached to the outer side surface of the dustproof oil seal ring 3, and the inner end surface of the cover 4 is attached to the end surface of the dustproof oil seal ring 3.

[0025] In the embodiment, the dustproof oil seal ring 3 is sleeved through the clamping groove 11.

[0026] Specifically, please refer to Figure 3 The connecting flanges 16 are arranged at the two ends of the shell 1, and a plurality of installation holes 17 are arranged on the connecting flanges 16.

[0027] In the embodiment, the shell 1 is installed through the cooperation of the connecting flanges 16, the installation holes 17 and the bolts.

[0028] Specifically, please refer to Figure 2 and Figure 4 The through hole 15 is arranged in the middle portion of the cover 4, and the transmission shaft 2 penetrates through the inner cavity of the through hole 15.

[0029] Specifically, please refer to Figures 1 to 3 The inner wall of the installation groove 12 is attached to the side surface of the cover 4, and the outer end surface of the cover 4 is flush with the end surface of the shell 1.

[0030] In this embodiment, the stability of the installation of the cover 4 in the inner cavity of the installation groove 12 is ensured, and the installation of the cover 4 does not affect the installation of the shell 1.

[0031] Working principle: when the magnetic fluid sealing device is installed, the nitrogen input pipe of the external device is sleeved on the top end of the plurality of first switch valves 8, and the first switch valve 8 and the second switch valve 10 are opened, so that the nitrogen is introduced from the first switch valve 8 and the gas injection port 7 to the inner cavity of the shell 1, and the air between the dustproof oil seal ring 3 and the bearing 5, the bearing 5 and the magnetic fluid sealing element 6, and the magnetic fluid sealing element 6 and the magnetic fluid sealing element 6 in the inner cavity of the shell 1 is extruded from the exhaust port 9 and the second switch valve 10 by using nitrogen, so that the nitrogen is filled between the dustproof oil seal ring 3 and the bearing 5, the bearing 5 and the magnetic fluid sealing element 6, and the magnetic fluid sealing element 6 and the magnetic fluid sealing element 6, and at this time, the first switch valve 8 and the second switch valve 10 are closed, so that the inner cavity of the shell 1 is in a state of being filled with nitrogen.

[0032] When the transmission shaft 2 rotates, the bearing 5 supports the transmission shaft 2, and the dustproof oil seal ring 3 and the magnetic fluid sealing element 6 seal between the shell 1 and the transmission shaft 2.

[0033] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any skilled person in the art can make equivalent replacement or change according to the technical scheme and improvement concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A two-stage magnetohydrodynamic sealing device with nitrogen protection, comprising a housing (1), characterized in that: The inner cavity of the housing (1) is fixedly fitted with two bearings (5), and the inner side of the two bearings (5) is fitted with a drive shaft (2). The inner cavity of the housing (1) is fitted with two magnetic fluid seals (6), and the inner side of the two magnetic fluid seals (6) is in contact with the outer side of the drive shaft (2). Dustproof oil seals (3) are fitted at both ends of the inner cavity of the housing (1). A cover (4) is installed at both ends of the housing (1). Multiple air injection ports (7) are provided at the top of the housing (1). A first switch valve (8) is fixedly installed at the top of the multiple air injection ports (7). Multiple exhaust ports (9) are provided at the bottom of the housing (1). A second switch valve (10) is fixedly installed at the bottom of the multiple exhaust ports (9).

2. The dual-stage magnetohydrodynamic sealing device with nitrogen protection according to claim 1, characterized in that: The housing (1) has mounting grooves (12) at both ends, and the inner walls of the two mounting grooves (12) are provided with multiple screw holes (13). The cover (4) is fitted into the inner cavity of the mounting groove (12), and multiple bolts (14) are fitted onto the cover (4). The ends of the multiple bolts (14) are threaded into the inner cavity of the screw holes (13).

3. The dual-stage magnetohydrodynamic sealing device with nitrogen protection according to claim 2, characterized in that: Both ends of the inner cavity of the housing (1) are provided with a mounting groove (11). The dustproof oil seal ring (3) is fitted into the inner cavity of the mounting groove (11). The inner side of the dustproof oil seal ring (3) is in contact with the side of the drive shaft (2). The inner wall of the mounting groove (11) is in contact with the outer side of the dustproof oil seal ring (3). The inner end face of the cover (4) is in contact with the end face of the dustproof oil seal ring (3).

4. The dual-stage magnetohydrodynamic sealing device with nitrogen protection according to claim 1, characterized in that: Both ends of the housing (1) are provided with connecting flanges (16), and the connecting flanges (16) are provided with multiple mounting holes (17).

5. A two-stage magnetohydrodynamic sealing device with nitrogen protection according to claim 1, characterized in that: The cover (4) has a perforation (15) in the middle, and the drive shaft (2) passes through the inner cavity of the perforation (15).

6. A two-stage magnetohydrodynamic sealing device with nitrogen protection according to claim 2, characterized in that: The inner wall of the mounting groove (12) fits against the side of the cover (4), and the outer end face of the cover (4) is flush with the end face of the shell (1).

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