阅读说明：本技术 使用具有极齿结构的轴向充磁永久磁铁环的磁流体密封装置 (Magnetic fluid seal using axially magnetized permanent magnet ring with pole tooth structure ) 是由 刘嘉伟 李德才 于 2021-09-07 设计创作，主要内容包括：本发明涉及一种使用具有极齿结构的轴向充磁永久磁铁环的磁流体密封,包括外壳、隔磁环和永久磁铁环。本发明提出了一种新型磁流体密封,该结构解决了磁性液体密封经典结构存在的极齿因主轴轴向跳动而磕碰损坏的问题、大间隙下密封性能差的问题和极齿结构因尺寸微小而存在的安装困难和加工工艺差的问题,使得该密封技术成功应用于磁性液体密封的多种场合之中。(The invention relates to a magnetic fluid seal using an axial magnetizing permanent magnet ring with a pole tooth structure. The invention provides a novel magnetic fluid seal, which solves the problems of pole teeth of a magnetic liquid seal classical structure that the pole teeth are collided and damaged due to axial runout of a main shaft, the sealing performance under a large gap is poor, and the pole teeth structure is difficult to install and poor in machining process due to small size, so that the sealing technology is successfully applied to various occasions of magnetic liquid seal.)

1. A magnetic fluid seal using an axial magnetizing permanent magnet ring with a pole tooth structure comprises a shell (2), a magnetism isolating ring (3) and a permanent magnet ring (4); the method is characterized in that: the magnetism isolating ring (3) and the permanent magnet ring (4) are arranged on the inner wall of the shell (2) and sleeved on the shaft, the sleeving mode is that the magnetism isolating ring, the permanent magnet ring, the magnetism isolating ring, the permanent magnet ring and the magnetism isolating ring are sequentially sleeved on the shaft at intervals, a gap is reserved between the inner circular surface of the magnetism isolating ring (3) and the permanent magnet ring (4) and the outer circular surface of the shaft section of the shaft (1), the gap is filled with magnetic fluid (9) for sealing, the magnetic lines of force generated by magnetization are gathered in the sealing gap by the magnetism isolating ring, magnetic field gradient generated by the magnetic ring on the ring surface enables the magnetic fluid to form an O-shaped sealing ring, the O-shaped sealing ring has certain pressure resistance, a pole tooth structure is arranged on the inner circular surface of the permanent magnet ring, wherein the tooth width is at least 0.5mm, the tooth height and the tooth pitch are not smaller than the tooth width, the structure can fully utilize the tip effect of the magnet to realize multi-stage sealing at the same axial length by using the pole tooth structure, the sealing capability is obviously improved.

2. A magnetic fluid seal using an axially charged permanent magnet ring with a tooth configuration as claimed in claim 1 wherein: the size of a gap between the inner circular surfaces of the magnetism isolating ring (3) and the permanent magnet ring (4) and the outer circular surface of the shaft section of the shaft (1) is 0.05-0.5 mm.

3. A magnetic fluid seal for an axial through-hole configuration magnetic source as claimed in claim 1 wherein: the permanent magnet rings (4) are axial magnetizing type annular magnets, the magnetizing directions of the adjacent permanent magnet rings are opposite, the number of the permanent magnet rings is at least 1, the ring thickness is at least 3mm, and the ring width is not larger than the ring thickness.

4. A magnetic fluid seal using an axially charged permanent magnet ring with a tooth configuration as claimed in claim 1 wherein: the magnetic isolation ring (3) is positioned on the outer circular surface and the end surface of the two end rings and is provided with a ring groove at a necessary position, and a sealing ring (6) is arranged in the ring groove.

5. The magnetic isolating ring (3) and the end cap (8) of the housing (2) as claimed in claim 1 are made of a 304 stainless steel non-magnetic conductive material, and the thickness of the permanent magnet ring is greater than that of the magnetic isolating ring.

6. A magnetic fluid seal using an axially charged permanent magnet ring with a tooth configuration as claimed in claim 1 wherein: the magnetic isolation bearing is characterized by further comprising a left bearing (7) and a right bearing (5), wherein the left bearing (7) and the right bearing (5) are respectively sleeved on the shaft (1), and the left bearing (7) is arranged on the left sides of the magnetic isolation ring (3) and the permanent magnet ring (4) and is in contact with the magnetic isolation ring; the right bearing (5) is arranged on the right sides of the magnetism isolating ring (3) and the permanent magnet ring (4) and is in contact with the magnetism isolating ring.

Technical Field

The invention belongs to the field of mechanical engineering sealing, and particularly relates to a magnetic fluid seal using an axial magnetizing permanent magnet ring

And (5) sealing the device.

Background

The magnetic fluid seal is characterized in that magnetic field force generated by the permanent magnet in the seal gap is utilized to firmly fix the magnetic fluid in the seal gap, so that the magnetic fluid can resist pressure difference on two sides, and the sealing effect is achieved.

Under the working condition of high-speed rotation, the classic magnetic fluid seal is easy to generate the jumping of a main shaft due to the tolerance of the inner diameter of a bearing, a common polar tooth structure is easy to collide and damage, so that the sealing device is poor in reliability and high in rejection rate, most of the schemes for solving the problem are the improvement of thickening the polar teeth and increasing the sealing gap on the basis of the classic tooth shape, the pressure resistance of the magnetic liquid seal is remarkably reduced along with the increase of the sealing gap, and in addition, the problems of difficult installation, poor processing technology and the like exist due to the small size of the polar tooth structure.

Disclosure of Invention

The invention aims to provide a magnetic fluid sealing device using an axial magnetizing permanent magnet ring with a pole tooth structure, which has the pole tooth structure, and solves the problems of pole tooth collision and damage caused by axial runout of a main shaft, poor sealing performance under a large gap and poor processing technology caused by small size of the pole tooth structure in a magnetic fluid sealing classical structure, so that the sealing technology is successfully applied to occasions with large axial runout.

The patent carries out finite element simulation aiming at a large number of magnetic liquid sealing examples, analyzes the simulation result and provides a reasonable design scheme of the structure.

The technical scheme of the invention is as follows: the magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure comprises a shell, a magnetism isolating ring and a permanent magnet ring; the method is characterized in that: the magnetic isolation ring and the permanent magnet ring are arranged on the inner wall of the shell and sleeved on the shaft, the sleeving mode is that the magnetic isolation ring, the permanent magnet ring, the magnetic isolation ring, the permanent magnet ring and the magnetic isolation ring are sequentially sleeved on the shaft at intervals, a gap is reserved between the inner circular surfaces of the magnetic isolation ring and the permanent magnet ring and the outer circular surface of the shaft section of the shaft, magnetic fluid is filled in the gap for sealing, magnetic lines of force generated by magnetization of the magnetic isolation ring are gathered in the sealing gap, magnetic field gradient generated by the magnetic ring on the circular surface enables the magnetic fluid to form an O-shaped sealing ring, the O-shaped sealing ring has certain pressure resistance, a pole tooth structure is arranged on the inner circular surface of the permanent magnet ring, the tooth width is at least 0.5mm, the tooth height and the tooth pitch are not smaller than the tooth width, the structure can also fully utilize the tip effect of the magnet to realize multi-stage sealing at the same axial length by taking advantage of the pole tooth structure, and the sealing capability is obviously improved.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the size of a gap between the inner circular surface of the magnetism isolating ring, the inner circular surface of the permanent magnet ring and the outer circular surface of the shaft section is 0.05-0.5 mm.

The magnetic fluid seal of the axial through hole structure magnetic source is characterized in that: the permanent magnet rings (4) are axial magnetizing type annular magnets, the magnetizing directions of the adjacent permanent magnet rings are opposite, the number of the permanent magnet rings is at least 1, the ring thickness is at least 3mm, and the ring width is not larger than the ring thickness.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the magnetic isolating ring is provided with annular grooves at necessary positions on the outer circular surfaces and the end surfaces of the two end rings, and sealing rings are arranged in the annular grooves.

The magnetism isolating ring is made of 304 stainless steel non-magnetic conductive materials, and the thickness of the permanent magnet ring is 1-5 times that of the magnetism isolating ring.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the permanent magnet bearing is characterized by also comprising a left bearing and a right bearing, wherein the left bearing and the right bearing are respectively sleeved on the shaft, and the left bearing is arranged on the left sides of the magnetism isolating ring and the permanent magnet ring and is in contact with the magnetism isolating ring; the right bearing is arranged on the right sides of the magnetism isolating ring and the permanent magnet ring and is in contact with the magnetism isolating ring.

Drawings

FIG. 1 is a schematic structural view of a magnetic fluid seal having an axially charged permanent magnet ring with a tooth configuration according to an embodiment of the present invention; the serial number designations and corresponding designations in the drawings are as follows: 1-shaft, 2-shell, 3-magnetism isolating ring, 4-permanent magnet ring, 5-right bearing, 6-sealing ring, 7-right bearing, 8-end cover, 9-magnetofluid; FIG. 2 is a cross-sectional view of a 4-permanent magnet ring; FIG. 3 is a graph of the seal gap field strength profile.

Detailed Description

The invention will be further explained with reference to the drawings.

As shown in fig. 1, the magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure comprises a shell, a magnetism isolating ring and a permanent magnet ring; the method is characterized in that: the magnetism isolating ring and the permanent magnet ring are arranged on the inner wall of the shell and sleeved on the shaft in a sleeving mode, the magnetism isolating ring, the permanent magnet ring and the magnetism isolating ring are sequentially sleeved on the shaft at intervals, a gap is reserved between the inner circular surfaces of the magnetism isolating ring and the permanent magnet ring and the outer circular surface of the shaft section of the shaft, magnetic fluid is filled in the gap for sealing, magnetic lines of force generated by magnetization of the magnetism isolating ring are gathered in the sealing gap, magnetic field gradients generated by the magnetic ring on the circular surface enable the magnetic fluid to form an O-shaped sealing ring, the O-shaped sealing ring has certain pressure resistance, and a pole tooth structure is arranged on the inner circular surface of the permanent magnet ring, wherein the tooth width is at least 0.5mm, and the tooth height and the tooth pitch are not smaller than the tooth width.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the size of a gap between the inner circular surface of the magnetism isolating ring, the inner circular surface of the permanent magnet ring and the outer circular surface of the shaft section is 0.05-0.5 mm, the structure uses the pole tooth structure for reference, and meanwhile, the tip effect of the magnet can be fully utilized to realize multi-stage sealing in the same axial length, so that the sealing capacity is remarkably improved.

The magnetic fluid seal of the axial through hole structure magnetic source is characterized in that: the permanent magnet rings are axial magnetizing type annular magnets, the magnetizing directions of the adjacent permanent magnet rings are opposite, the number of the permanent magnet rings is at least 1, the ring thickness is at least 3mm, and the ring width is not larger than the ring thickness.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the magnetic isolating ring is provided with annular grooves at necessary positions on the outer circular surfaces and the end surfaces of the two end rings, and sealing rings are arranged in the annular grooves.

The magnetism isolating ring is made of 304 stainless steel non-magnetic conductive materials, and the thickness of the permanent magnet ring is 1-5 times that of the magnetism isolating ring.

The magnetic fluid seal using the axial magnetizing permanent magnet ring with the pole tooth structure is characterized in that: the permanent magnet bearing is characterized by also comprising a left bearing and a right bearing, wherein the left bearing and the right bearing are respectively sleeved on the shaft, and the left bearing is arranged on the left sides of the magnetism isolating ring and the permanent magnet ring and is in contact with the magnetism isolating ring; the right bearing is arranged on the right sides of the magnetism isolating ring and the permanent magnet ring and is in contact with the magnetism isolating ring.