CN209587141U - A kind of double ladder device for sealing magnetic fluid of symmetric form - Google Patents

Abstract

The purpose of the utility model is to provide a kind of double ladder device for sealing magnetic fluid of symmetric form, the double ladder device for sealing magnetic fluid of the symmetric form, including multi-diameter shaft, shell, the first from left pole shoe ring, a right pole shoe ring, intermediate sleeve, intermediate magnet ring；The multi-diameter shaft includes the secondary axis more than two that the maximum 1 grade of axis of diameter and diameter are sequentially reduced, and the secondary axis is successively arranged to two sides along the side of 1 grade of axis, is boundary bilateral symmetry with the intermediate radial section of 1 grade of axis.The purpose of this utility model is to solve the lower problem of pressure resistance performance existing for existing sealing device, so that the sealing technique is successfully applied in the fields such as high-speed overload.

Description

A kind of double ladder device for sealing magnetic fluid of symmetric form

Technical field

The utility model belongs to sealing field of mechanical engineering, and in particular to a kind of double ladder magnet fluid sealing dresses of symmetric form It sets.

Background technique

In large-diameter rotary shaft magnet fluid sealing occasion, due to the bias of the factors such as process and assemble error, vibration generation The pressure-resistant performance of magnet fluid sealing is caused to decline；On the other hand under the effect of high speed centrifugation power magnet fluid sealing performance also under Drop, therefore the pressure-resistant performance for improving large-diameter magnetic fluid dynamic sealing is one of hot issue of current research.

Reduce Shaft Eccentricity On The Capacity of Magnetic Fluid Seals Against Pressure Difference performance influence method first is that by improve magnetic fluid it is close Seal structure, the sealing device as described in documents 1 (patent of Publication No. CN105465373A).Although document above institute The relatively common magnetic fluid seal performance of the sealing device stated is greatly improved, but its sealing device is not considered to turn Influence of the eccentric shaft to magnet fluid sealing pressure resistance performance.

Utility model content

The purpose of the utility model is to provide a kind of double ladder device for sealing magnetic fluid of symmetric form, to solve existing sealing The problem that device for sealing magnetic fluid pressure resistance performance declines caused by device is acted on because of shaft bias and centrifugal force, so that the sealing skill Art Successful utilization is in the occasion that large-diameter rotates.

The technical solution of the utility model is as follows:

The double ladder device for sealing magnetic fluid of the symmetric form, including multi-diameter shaft, shell, the first from left pole shoe ring, a right pole shoe Ring, intermediate sleeve, intermediate magnet ring；

The multi-diameter shaft includes time 1 grade of axis more than two that the maximum 1 grade of axis of diameter and diameter are sequentially reduced, described Time 1 grade of axis successively arrange to two sides along the side of 1 grade of axis, be boundary bilateral symmetry with the intermediate radial section of 1 grade of axis；

The first from left pole shoe ring, intermediate magnet ring, a right pole shoe ring are successively set on the inner wall of shell, the first from left pole The left end face contact of the right side of boots ring and intermediate magnet ring, the left end of the right side of intermediate magnet ring and a right pole shoe ring Face contact；The corresponding 1 grade of axis setting of the first from left pole shoe ring, intermediate magnet ring, a right pole shoe ring, wherein intermediate permanent magnetism The middle part of the corresponding 1 grade of axis of body ring；

The intermediate sleeve is set on the periphery of 1 grade of axis, the periphery of intermediate sleeve and intermediate magnet ring Inner headed face is corresponding, and there are gaps between them；

Outside on the intermediate sleeve left side is equipped with bulge loop I；In on the right side of the first from left pole shoe ring Portion is equipped with annular groove I, and the left side of the bulge loop I extends close to the bottom surface of annular groove I, annular groove along axial direction to the left The bottom surface of I is equipped with pole tooth I, and the pole tooth I is along axial right extension, and there are gap, the gaps between the left side of bulge loop I In be equipped with magnetic fluid；Lateral wall of the periphery of the bulge loop I close to annular groove I, the periphery and annular groove of bulge loop I Magnetic fluid is filled between the lateral wall of I, for the inner headed face of the bulge loop I close to the inner sidewall of annular groove I, bulge loop I's is interior Magnetic fluid is filled between disc and the inner sidewall of annular groove I；

The inner headed face of the first from left pole shoe ring radially extends to the periphery of 1 grade of axis, between the periphery of 1 grade of axis There are gap, the inner headed face of the first from left pole shoe ring is equipped with pole tooth VI, and the pole tooth VI radially prolongs to the periphery of 1 grade of axis It stretches, there are gap between the periphery of 1 grade of axis, magnetic fluid is equipped in the gap；

Part on the right side of the first from left pole shoe ring between annular groove I and 1 grade of axis is equipped with pole tooth VII, institute The pole tooth VII stated extends along axial direction to the left side of intermediate sleeve, and there are gap, the gaps between the left side of intermediate sleeve In be equipped with magnetic fluid；

Outside on the right side of the intermediate sleeve is equipped with bulge loop II；On the left side of one pole shoe ring of the right side Middle part is equipped with annular groove II, and the right side of the bulge loop II extends close to the right the bottom surface of annular groove II, ring along axial direction The bottom surface of connected in star II is equipped with pole tooth II, the pole tooth II along axial left extension, between the right side of bulge loop II there are Gap is equipped with magnetic fluid in the gap；For the periphery of the bulge loop II close to the lateral wall of annular groove II, bulge loop II's is outer Magnetic fluid is filled between disc and the lateral wall of annular groove II, the inner headed face of the bulge loop II is close to annular groove II's Inner sidewall is filled with magnetic fluid between the inner headed face of bulge loop II and the inner sidewall of annular groove II；

The inner headed face of one pole shoe ring of the right side radially extends to the periphery of 1 grade of axis, between the periphery of 1 grade of axis There are gap, the inner headed face of a right pole shoe ring is equipped with pole tooth VIII, and the pole tooth VIII radially prolongs to the periphery of 1 grade of axis It stretches, there are gap between the periphery of 1 grade of axis, magnetic fluid is equipped in the gap；

Part on the left side of one pole shoe ring of the right side between annular groove II and 1 grade of axis is equipped with pole tooth Ⅸ, The pole tooth Ⅸ extends along axial direction to the right side of intermediate sleeve, and there are gaps between the right side of intermediate sleeve, between being somebody's turn to do Magnetic fluid is equipped in gap.

The pole interval tooth I setting 1-10, the pole interval tooth II setting 1-10, the pole tooth VI is spaced It is arranged 1-10, the pole tooth VII is spaced setting 1-10, the interval of the pole tooth VIII setting 1-10 a, described pole tooth Ⅸ Interval setting 1-10.

The periphery of the first from left pole shoe ring, a right pole shoe ring is equipped with annular groove III, the annular groove Sealing ring I is equipped in III.

The secondary axis that the left and right sides of 1 grade of axis is set gradually respectively is 2-10 grades of axis, 1 grade of axis, 2-10 The diameter of grade axis is sequentially reduced；

It further include the second from left pole shoe ring, right diode boot ring, left magnet ring, right magnet ring；

The second from left pole shoe ring is equipped with one group or more, and interval is set on the inner wall of shell, the 2-10 on the left of corresponding 1 grade of axis Grade axis setting, from right to left, the region of corresponding two secondary axis of every group of the second from left pole shoe ring, the left side near intermediate sleeve It is equipped with left magnet ring between diode boot ring and intermediate sleeve, is equipped with left magnet ring between each group the second from left pole shoe ring；

On the right side of the corresponding 1 grade of axis of the right diode boot ring-setting of grade axis, from left to right, every group of right diode boot ring is corresponding The region of two secondary axis is equipped with right permanent magnet between the right diode boot ring and intermediate sleeve near intermediate sleeve Ring is equipped with right magnet ring between the right diode boot ring of each group；

Anchor ring I, end face I, anchor ring II, end face II are respectively equipped on the second from left pole shoe ring and right diode boot ring；

The end face for the secondary axis that each end face I distinguishes corresponding even level is corresponding；On the end face I Equipped with pole tooth III；The end face of secondary axis of the pole tooth III along axial direction to each even level extends, with each even level There are gap between the end face of secondary axis, magnetic fluid is placed in the gap；

The part of close multi-diameter shaft on each end face II end face phase with the secondary axis of previous odd level respectively Corresponding, the part of the close multi-diameter shaft of end face II is equipped with pole tooth IV；Time of the pole tooth IV along axial direction to each odd level The end face of grade axis extends, and there are gap between the end face of the secondary axis of each even level, magnetic fluid is placed in the gap；

The periphery for the secondary axis that each anchor ring I distinguishes corresponding even level is corresponding, anchor ring I with There are gap between the periphery of the secondary axis of each even level, magnetic fluid is placed in the gap；

The periphery of the secondary axis of the anchor ring II corresponding odd level is corresponding, and anchor ring II is equipped with pole Tooth V, the pole tooth V radially extend to the periphery of the secondary axis of each odd level, the secondary axis with each odd level Periphery between there are gap, magnetic fluid is placed in the gap.

The pole interval tooth III setting 1-10, the interval of pole tooth IV setting 1-10, between the pole tooth V Every setting 1-10.

The periphery of the second from left pole shoe ring and right diode boot ring is equipped with annular groove IV, the annular groove IV It is interior to be equipped with sealing ring II.

The left magnet ring is contrary with the intermediate magnetic line of force of magnet ring, the right magnet ring and centre The magnetic line of force of magnet ring is contrary, and the left magnet ring is identical as the magnetic line of force direction of right magnet ring.

The double ladder device for sealing magnetic fluid of the symmetric form, further include right sleeve, the right sleeve is set to the rightmost side Right diode boot ring on the outside of, contacted respectively with the right diode boot ring and end cap of the rightmost side.

The double ladder device for sealing magnetic fluid of the symmetric form, further include left magnetism-isolating loop, right magnetism-isolating loop, left bearing and right axle It holds；The left magnetism-isolating loop is set to the left side of the second from left pole shoe ring of the leftmost side, is close to the inner wall setting of shell；The right side is every magnetic It is located on the right side of the right diode boot ring in the rightmost side, is close to the inner headed face setting of right sleeve；The left bearing is set in multi-diameter shaft On left end, positioned at the left side of left magnetism-isolating loop；The right bearing is set on the inner headed face of right sleeve, positioned at the right side of right magnetism-isolating loop Side.

Magnet fluid sealing is to generate magnetic field force in seal clearance using permanent magnet magnetic fluid is secured firmly between sealing In gap, the pressure difference of two sides is resisted, to achieve the effect that sealing.

The utility model increases T-type sleeve by designing a kind of multi-diameter shaft on the ladder of multi-diameter shaft, connects with axle thread It connects, labyrinth sealing is then constituted with arcuate pole shoe, and combine symmetrical double staged pole shoes, in multi-diameter shaft and ladder pole shoe Magnetic fluid is injected in axial gap, to realize a kind of double ladder magnet fluid sealings of symmetric form.This T-type sleeve matches synapsid pole The structure of boots further enhances the ability of the sealing pressure resistance of entire device for sealing magnetic fluid.

The utility model can preferably overcome existing sealing device to cause because of operating conditions such as eccentric, centrifugal force and wide arc gaps Sealing performance decline problem the magnetic fluid in seal failure is greatly reduced using the utility model sealing device Loss reduces the influences of the factors to magnet fluid sealing performance such as eccentric and centrifugation, improves the pressure resistance of common magnet fluid sealing Ability and sealing reliability expand its range of safety operation.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of sealing device described in the utility model;

Each serial number mark and corresponding title are as follows in figure:

1- multi-diameter shaft, 2- shell, 3- the first from left pole shoe ring, 4- the second from left pole shoe ring, one pole shoe ring of the right side 5-, the right diode boot ring of 6-, 7- intermediate sleeve, the left magnet ring of 8-, the centre 9- magnet ring, the right magnet ring of 10-, 11- bulge loop I, 12- annular groove I, The pole 13- tooth I, 14- bulge loop II, 15- annular groove II, 16- pole tooth II, 17- anchor ring I, 18- end face I, 19- anchor ring II, The end face the 20- pole II, 21- tooth III, the pole 22- tooth IV, the pole 23- tooth V, 24- annular groove III, 25- sealing ring I, 26- annular are recessed Slot IV, 27- sealing ring II, 28- end cap, the left magnetism-isolating loop of 29-, the right magnetism-isolating loop of 30-, 31- left bearing, 32- right bearing, the right set of 33- Cylinder, the pole 34- tooth VI, the pole 35- tooth VII, the pole 36- tooth VIII, the pole 37- tooth Ⅸ.

101-1 grades of axis.

Specific embodiment

The utility model is described in further detail with reference to the accompanying drawing.

As shown in Figure 1, forever including multi-diameter shaft 1, shell 2, the first from left pole shoe ring 3, a right pole shoe ring 5, intermediate sleeve 7, centre Magnet ring 9；

The multi-diameter shaft 1 includes the secondary axis more than two that the maximum 1 grade of axis 101 of diameter and diameter are sequentially reduced, The secondary axis is successively arranged to two sides along the side of 1 grade of axis 101, is boundary left and right with the intermediate radial section of 1 grade of axis 101 Symmetrically；

The first from left pole shoe ring 3, intermediate magnet ring 9, a right pole shoe ring 5 are successively set on the inner wall of shell 2, left The left end face contact of the right side of one pole shoe ring 3 and intermediate magnet ring 9, the right side of intermediate magnet ring 9 and a right pole shoe The left end face contact of ring 5；The corresponding 1 grade of axis 101 of the first from left pole shoe ring 3, intermediate magnet ring 9, a right pole shoe ring 5 is set It sets, wherein the middle part of the corresponding 1 grade of axis 101 of intermediate magnet ring 9；

The intermediate sleeve 7 is set on the periphery of 1 grade of axis 101, the periphery of intermediate sleeve 7 and intermediate permanent magnet The inner headed face of ring 9 is corresponding, and there are gaps between them；

Outside on 7 left side of intermediate sleeve is equipped with bulge loop I11；On the right side of the first from left pole shoe ring 3 Middle part be equipped with annular groove I12, the left side of the bulge loop I11 extends close to the bottom of annular groove I12 along axial direction to the left Face, the bottom surface of annular groove I12 are equipped with pole tooth I13, left side of the pole tooth I13 along axial right extension, with bulge loop I11 Between there are gap, magnetic fluid is equipped in the gap；The periphery of the bulge loop I11 close to annular groove I12 lateral wall, Magnetic fluid, the inner circle face paste of the bulge loop I11 are filled between the periphery of bulge loop I11 and the lateral wall of annular groove I12 The inner sidewall of near-ring connected in star I12 is filled with magnetic fluid between the inner headed face of bulge loop I11 and the inner sidewall of annular groove I12；

The inner headed face of the first from left pole shoe ring 3 radially extends to the periphery of 1 grade of axis 101, outer with 1 grade of axis 101 There are gap between disc, the inner headed face of the first from left pole shoe ring 3 is equipped with pole tooth VI 34, and the pole tooth VI 34 is radially to 1 grade The periphery of axis 101 extends, and there are gap between the periphery of 1 grade of axis 101, is equipped with magnetic fluid in the gap；

Part on the right side of the first from left pole shoe ring 3 between annular groove I12 and 1 grade of axis 101 is equipped with pole Tooth VII 35, the pole tooth VII 35 extend to the left side of intermediate sleeve 7 along axial direction, stay between the left side of intermediate sleeve 7 There is gap, magnetic fluid is equipped in the gap；

Outside on the right side of the intermediate sleeve 7 is equipped with bulge loop II14；The left side of one pole shoe ring 5 of the right side On middle part be equipped with annular groove II15, the right side of the bulge loop II14 extends close to the right annular groove II15 along axial direction Bottom surface, the bottom surface of annular groove II15 is equipped with pole tooth II16, and the pole tooth II16 is along axial left extension, with bulge loop II14 Right side between there are gap, magnetic fluid is equipped in the gap；The periphery of the bulge loop II14 is close to annular groove The lateral wall of II15 is filled with magnetic fluid between the periphery of bulge loop II14 and the lateral wall of annular groove II15, described is convex Inner sidewall of the inner headed face of ring II14 close to annular groove II15, the inner sidewall of the inner headed face and annular groove II15 of bulge loop II14 Between be filled with magnetic fluid；

The inner headed face of one pole shoe ring 5 of the right side radially extends to the periphery of 1 grade of axis 101, outer with 1 grade of axis 101 There are gap between disc, the inner headed face of a right pole shoe ring 5 is equipped with pole tooth VIII 36, and the pole tooth VIII 36 is radially to 1 grade The periphery of axis 101 extends, and there are gap between the periphery of 1 grade of axis 101, is equipped with magnetic fluid in the gap；

Part on the left side of one pole shoe ring 5 of the right side between annular groove II15 and 1 grade of axis 101 is equipped with pole Tooth Ⅸ 37, the pole tooth Ⅸ 37 extend to the right side of intermediate sleeve 7 along axial direction, stay between the right side of intermediate sleeve 7 There is gap, magnetic fluid is equipped in the gap.

The pole interval tooth I13 setting 1-10, the pole interval tooth II16 setting 1-10, the pole tooth VI 34 interval settings 1-10, the interval of pole tooth VII 35 setting 1-10, the interval of pole tooth VIII 36 setting 1-10, institute The interval of pole tooth Ⅸ 37 setting 1-10 stated.

The periphery of the first from left pole shoe ring 3, a right pole shoe ring 5 is equipped with annular groove III24, and the annular is recessed Sealing ring III25 is equipped in slot I24.

The secondary axis that the left and right sides of 1 grade of axis 101 is set gradually respectively is 2-10 grades of axis, 1 grade of axis 101, the diameter of 2-10 grades of axis is sequentially reduced；

It further include the second from left pole shoe ring 4, right diode boot ring 6, left magnet ring 8, right magnet ring 10；

The second from left pole shoe ring 4 is equipped with one group or more, and interval is set on the inner wall of shell 2, corresponding 1 grade of axis, 101 left side The setting of 2-10 grade axis, from right to left, the region of corresponding two secondary axis of every group of the second from left pole shoe ring 4 is described near centre It is equipped with left magnet ring 8 between the second from left pole shoe ring 4 and intermediate sleeve 7 of sleeve 7, is set between each group the second from left pole shoe ring 4 There is left magnet ring 8；

The 2-10 grade axis setting on corresponding 1 grade of axis, 101 right side of the right diode boot ring 6, from left to right, every group of right diode boot Ring 6 corresponds to the region of two secondary axis, is equipped between the right diode boot ring 6 and intermediate sleeve 7 near intermediate sleeve 7 Right magnet ring 10 is equipped with right magnet ring 10 between the right diode boot ring 6 of each group；

Be respectively equipped in the second from left pole shoe ring 4 and right diode boot ring 6 anchor ring I17, end face I18, anchor ring II19, End face II20；

The end face for the secondary axis that each end face I18 distinguishes corresponding even level is corresponding；The end face I18 is equipped with pole tooth III21；The end face of secondary axis of the pole tooth III21 along from axial direction to each even level extends, and each There are gap between the end face of the secondary axis of even level, magnetic fluid is placed in the gap；

The part of close multi-diameter shaft 1 on each end face II20 end face with the secondary axis of previous odd level respectively Corresponding, the part of the close multi-diameter shaft 1 of end face II20 is equipped with pole tooth IV 22；The pole tooth IV 22 is along axial direction to each surprise The end face of the secondary axis of several levels extends, and there are gap between the end face of the secondary axis of each even level, magnetic fluid is placed between this In gap；

The periphery for the secondary axis that each anchor ring I17 distinguishes corresponding even level is corresponding, anchor ring There are gap between the periphery of the secondary axis of I17 and each even level, magnetic fluid is placed in the gap；

The periphery of the secondary axis of the anchor ring II19 corresponding odd level is corresponding, sets on anchor ring II19 There is pole tooth V 23, the pole tooth V 23 radially extends to the periphery of the secondary axis of each odd level, with each odd level Secondary axis periphery between there are gap, magnetic fluid is placed in the gap.

The pole interval tooth III21 setting 1-10, the interval of pole tooth IV 22 setting 1-10；The pole tooth V 23 interval settings 1-10.

The periphery of the second from left pole shoe ring 4 and right diode boot ring 6 is equipped with annular groove IV 26, and the annular is recessed Sealing ring IV 27 is equipped in slot II26.

The left magnet ring 8 is contrary with the intermediate magnetic line of force of magnet ring 9, the right magnet ring 10 with The magnetic line of force of intermediate magnet ring 9 is contrary, the magnetic line of force direction phase of the left magnet ring 8 and right magnet ring 10 Together.

The double ladder device for sealing magnetic fluid of the symmetric form, further include right sleeve 33, and the right sleeve 33 is set to most 6 outside of right diode boot ring on right side, contacts with the right diode boot ring 6 and end cap 28 of the rightmost side respectively.

The double ladder device for sealing magnetic fluid of the symmetric form, further include left magnetism-isolating loop 29, right magnetism-isolating loop 30, left bearing 31 With right bearing 32；The left magnetism-isolating loop 29 is set to the left side of the second from left pole shoe ring 4 of the leftmost side, is close to the inner wall setting of shell 2； The right magnetism-isolating loop 30 is set to the right side of the right diode boot ring 6 in the rightmost side, is close to the inner headed face setting of right sleeve 33；The left side Bearing 31 is set on 1 left end of multi-diameter shaft, positioned at the left side of left magnetism-isolating loop 29；The right bearing 32 is set to the interior of right sleeve 33 On disc, positioned at the right side of right magnetism-isolating loop 30.

Claims (9)

1. a kind of double ladder device for sealing magnetic fluid of symmetric form, including multi-diameter shaft (1), shell (2), the first from left pole shoe ring (3), the right side one Pole shoe ring (5), intermediate sleeve (7), intermediate magnet ring (9), it is characterised in that:

The multi-diameter shaft (1) includes the maximum 1 grade of axis (101) of diameter and the secondary axis more than two that diameter is sequentially reduced, The secondary axis is successively arranged to two sides along the side of 1 grade of axis (101), is boundary with the intermediate radial section of 1 grade of axis (101) Symmetrically；

The first from left pole shoe ring (3), intermediate magnet ring (9), a right pole shoe ring (5) are successively set in the inner wall of shell (2) On, the left end face contact of the right side of the first from left pole shoe ring (3) and intermediate magnet ring (9), the right side of intermediate magnet ring (9) With the left end face contact of a right pole shoe ring (5)；The first from left pole shoe ring (3), intermediate magnet ring (9), a right pole shoe ring (5) Corresponding 1 grade of axis (101) setting, wherein the middle part of the corresponding 1 grade of axis (101) of intermediate magnet ring (9)；

The intermediate sleeve (7) is set on the periphery of 1 grade of axis (101), the periphery of intermediate sleeve (7) and intermediate permanent magnetism The inner headed face of body ring (9) is corresponding, and there are gaps between them；

Outside on described intermediate sleeve (7) left side is equipped with bulge loop I(11)；The right side of the first from left pole shoe ring (3) On middle part be equipped with annular groove I(12), the bulge loop I(11) left side extend close to annular groove I to the left along axial direction (12) bottom surface, annular groove I(12) bottom surface be equipped with pole tooth I(13), the pole tooth I(13) along axial right extension, with Bulge loop I(11) left side between there are gap, magnetic fluid is equipped in the gap；The bulge loop I(11) periphery close to Annular groove I(12) lateral wall, bulge loop I(11) periphery and annular groove I(12) lateral wall between be filled with magnetic current Body, the bulge loop I(11) inner sidewall of the inner headed face close to annular groove I(12), bulge loop I(11) inner headed face and annular it is recessed Slot I(12) inner sidewall between be filled with magnetic fluid；

The inner headed face of the first from left pole shoe ring (3) radially extends to the periphery of 1 grade of axis (101), with 1 grade of axis (101) There are gap between periphery, the inner headed face of the first from left pole shoe ring (3) is equipped with pole tooth VI (34), and the pole tooth VI (34) is along diameter Extend to the periphery of 1 grade of axis (101), there are gap between the periphery of 1 grade of axis (101), is equipped with magnetic current in the gap Body；

Part on the right side of the first from left pole shoe ring (3) between annular groove I(12) and 1 grade of axis (101) is equipped with Pole tooth VII (35), the pole tooth VII (35) extend along axial direction to the left side of intermediate sleeve (7), the left side with intermediate sleeve (7) There are gap between end face, magnetic fluid is equipped in the gap；

Outside on the right side of the intermediate sleeve (7) is equipped with bulge loop II(14)；The left end of one pole shoe ring of the right side (5) Middle part on face is equipped with annular groove II(15), the bulge loop II(14) to extend close to annular to the right along axial direction recessed for right side Slot II(15) bottom surface, annular groove II(15) bottom surface be equipped with pole tooth II(16), the pole tooth II(16) along an axial left side Extend, there are gap between the right side of bulge loop II(14), magnetic fluid is equipped in the gap；The bulge loop II(14) it is outer Lateral wall of the disc close to annular groove II(15), bulge loop II(14) periphery and annular groove II(15) lateral wall between Filled with magnetic fluid, the bulge loop II(14) inner sidewall of the inner headed face close to annular groove II(15), bulge loop II(14) Inner headed face and annular groove II(15) inner sidewall between be filled with magnetic fluid；

The inner headed face of one pole shoe ring of the right side (5) radially extends to the periphery of 1 grade of axis (101), with 1 grade of axis (101) There are gap between periphery, the inner headed face of a right pole shoe ring (5) is equipped with pole tooth VIII (36), and the pole tooth VIII (36) is along diameter Extend to the periphery of 1 grade of axis (101), there are gap between the periphery of 1 grade of axis (101), is equipped with magnetic current in the gap Body；

Part on the left side of one pole shoe ring of the right side (5) between annular groove II(15) and 1 grade of axis (101) is equipped with Pole tooth Ⅸ (37), the pole tooth Ⅸ (37) extend along axial direction to the right side of intermediate sleeve (7), the right side with intermediate sleeve (7) There are gap between end face, magnetic fluid is equipped in the gap.

2. the double ladder device for sealing magnetic fluid of symmetric form as described in claim 1, it is characterised in that: the pole tooth I(13) Interval setting 1-10, the pole tooth II(16) interval setting 1-10, pole tooth VI (34) interval setting 1-10, Pole tooth VII (35) interval setting 1-10, pole tooth VIII (36) interval setting 1-10, the pole tooth Ⅸ (37) interval setting 1-10.

3. the double ladder device for sealing magnetic fluid of symmetric form as described in claim 1, it is characterised in that: the first from left pole shoe ring (3), the periphery of a right pole shoe ring (5) is equipped with annular groove III(24), the annular groove III(24) it is interior equipped with close Seal I(25).

4. the double ladder device for sealing magnetic fluid of symmetric form as described in claim 1, it is characterised in that:

The secondary axis that the left and right sides of 1 grade of axis (101) is set gradually respectively is 2-10 grades of axis, 1 grade of axis (101), the diameter of 2-10 grades of axis is sequentially reduced；

It further include the second from left pole shoe ring (4), right diode boot ring (6), left magnet ring (8), right magnet ring (10)；

The second from left pole shoe ring (4) is equipped with one group or more, and interval is set on the inner wall of shell (2), and corresponding 1 grade of axis (101) is left The 2-10 grade axis of side is arranged, from right to left, the region of corresponding two secondary axis of every group of the second from left pole shoe ring (4), it is described near Left magnet ring (8) are equipped between the second from left pole shoe ring (4) and intermediate sleeve (7) of intermediate sleeve (7), each group the second from left pole Left magnet ring (8) are equipped between boots ring (4)；

2-10 grade axis setting on the right side of the corresponding 1 grade of axis (101) of the right diode boot ring (6), from left to right, every group of right diode boot The region of corresponding two, ring (6) secondary axis, the right diode boot ring (6) near intermediate sleeve (7) and intermediate sleeve (7) Between be equipped with right magnet ring (10), be equipped with right magnet ring (10) between the right diode boot ring (6) of each group；

Be respectively equipped with anchor ring I(17 in the second from left pole shoe ring (4) and right diode boot ring (6)), end face I(18), anchor ring II(19), end face II(20)；

Each end face I(18) respectively the end face of the secondary axis of corresponding even level it is corresponding；The end face I (18) it is equipped with pole tooth III(21)；The pole tooth III(21) extend along axial direction to the end face of the secondary axis of each even level, There are gap between the end face of the secondary axis of each even level, magnetic fluid is placed in the gap；

Each end face II(20) on close multi-diameter shaft (1) the part end face with the secondary axis of previous odd level respectively Corresponding, end face II(20) the part of close multi-diameter shaft (1) be equipped with pole tooth IV (22)；The pole tooth IV (22) is along axial direction Extend to the end face of the secondary axis of each odd level, there are gap, magnetic fluids between the end face of the secondary axis of each even level It is placed in the gap；

Each anchor ring I(17) respectively the periphery of the secondary axis of corresponding even level it is corresponding, anchor ring I (17) there are gap between the periphery of the secondary axis of each even level, magnetic fluid is placed in the gap；

The anchor ring II(19) corresponding odd level secondary axis periphery it is corresponding, anchor ring II(19) on set There is pole tooth V (23), the pole tooth V (23) radially extends to the periphery of the secondary axis of each odd level, with each surprise There are gap between the periphery of the secondary axis of several levels, magnetic fluid is placed in the gap.

5. the double ladder device for sealing magnetic fluid of symmetric form as claimed in claim 4, it is characterised in that: the pole tooth III (21) interval setting 1-10, pole tooth IV (22) interval setting 1-10, pole tooth V (23) the interval setting 1- 10.

6. the double ladder device for sealing magnetic fluid of symmetric form as claimed in claim 4, it is characterised in that: the second from left pole shoe ring (4) and the periphery of right diode boot ring (6) is equipped with annular groove IV (26), is equipped with sealing in the annular groove IV (26) Enclose II(27).

7. the double ladder device for sealing magnetic fluid of symmetric form as claimed in claim 4, it is characterised in that: the left magnet ring (8) contrary with the magnetic line of force of intermediate magnet ring (9), the right magnet ring (10) and intermediate magnet ring (9) The magnetic line of force is contrary, and the left magnet ring (8) is identical as the magnetic line of force direction of right magnet ring (10).

8. the double ladder device for sealing magnetic fluid of symmetric form as claimed in claim 4, it is characterised in that: further include right sleeve (33), the right sleeve (33) be set to the rightmost side right diode boot ring (6) on the outside of, respectively with the right diode boot ring of the rightmost side (6) it is contacted with end cap (28).

9. the double ladder device for sealing magnetic fluid of symmetric form as claimed in claim 8, it is characterised in that: further include left magnetism-isolating loop (29), right magnetism-isolating loop (30), left bearing (31) and right bearing (32)；The left magnetism-isolating loop (29) is set to the second from left pole of the leftmost side The inner wall setting of shell (2) is close in the left side of boots ring (4)；The right magnetism-isolating loop (30) is set to the right diode boot ring (6) in the rightmost side Right side, be close to right sleeve (33) inner headed face setting；The left bearing (31) is set on multi-diameter shaft (1) left end, is located at The left side of left magnetism-isolating loop (29)；The right bearing (32) is set on the inner headed face of right sleeve (33), is located at right magnetism-isolating loop (30) Right side.