JPH0431368U

JPH0431368U -

Info

Publication number: JPH0431368U
Application number: JP7264590U
Authority: JP
Priority date: 1990-07-10
Filing date: 1990-07-10
Publication date: 1992-03-13
Anticipated expiration: 2005-07-10
Also published as: JP2516192Y2

Description

[Brief explanation of drawings]

第１〜２図は本考案の第一実施例を示しており
、第１図は組み付け後の状態を示す断面図、第２
図は組み付け前の状態を示す断面図、第３〜４図
は本考案の第二実施例を示しており、第３図は第
１図同様の断面図、第４図は平面図、第５図は本
考案の第三実施例を、第６図は同第四実施例を、
第７図は同第五実施例を、第８図は同第六実施例
を、第９図は同第七実施例を、第１０図は同第八
実施例を、第１１図は同第九実施例を、第１２図
は同第十実施例を、それぞれ示す断面図、第１３
図は従来の磁性流体シール装置を組み込んだスピ
ンドルモータを示す断面図である。１……取付フランジ、２……ハウジング、３…
…回転軸、４……転がり軸受、５……ロータ、６
……磁性流体シール装置、７……永久磁石、７ａ
……外周面、７ｂ……内周面、８……ポールピー
ス、９……磁性流体、１０……円筒状空間、１２
……Ｏリング、１３……かしめ部、１４……傾斜
面、１５……段部、１６，１７……凹溝、１８…
…係止部、１９……外輪、２０……凹溝。 1 and 2 show the first embodiment of the present invention, FIG. 1 is a sectional view showing the state after assembly, and FIG.
The figure is a cross-sectional view showing the state before assembly, Figures 3 and 4 show a second embodiment of the present invention, Figure 3 is a cross-sectional view similar to Figure 1, Figure 4 is a plan view, and Figure 5 is a cross-sectional view showing the state before assembly. The figure shows the third embodiment of the present invention, and Figure 6 shows the fourth embodiment of the invention.
7 shows the fifth embodiment, FIG. 8 shows the sixth embodiment, FIG. 9 shows the seventh embodiment, FIG. 10 shows the eighth embodiment, and FIG. 11 shows the eighth embodiment. FIG. 12 is a sectional view showing the ninth embodiment, FIG. 12 is a sectional view showing the tenth embodiment, and FIG.
The figure is a sectional view showing a spindle motor incorporating a conventional magnetic fluid seal device. 1...Mounting flange, 2...Housing, 3...
... Rotating shaft, 4 ... Rolling bearing, 5 ... Rotor, 6
...Magnetic fluid sealing device, 7...Permanent magnet, 7a
...Outer circumferential surface, 7b...Inner circumferential surface, 8...Pole piece, 9...Magnetic fluid, 10...Cylindrical space, 12
... O-ring, 13 ... Caulked part, 14 ... Inclined surface, 15 ... Step part, 16, 17 ... Concave groove, 18 ...
...Locking portion, 19...Outer ring, 20...Concave groove.

Claims

[Scope of utility model registration request]

a first circumferential surface, a second circumferential surface concentric with the first circumferential surface, and an annular ring installed in a cylindrical space between the first circumferential surface and the second circumferential surface; a permanent magnet magnetized in the axial direction; at least one pair of pole pieces each formed in a ring shape and fixed to both sides of the permanent magnet with the permanent magnet sandwiched therebetween; and at least one pole piece. In a magnetic fluid sealing device comprising a magnetic fluid held in a seal gap between one peripheral edge of the pair of pole pieces and the first peripheral surface, the entire circumference or circumference of the other peripheral edge of the pair of pole pieces At least three positions in the direction are in contact with the second circumferential surface or are opposed to each other through a gap sufficiently smaller than the seal gap, and between the second circumferential surface and the circumferential surface of the permanent magnet. A magnetic fluid sealing device characterized in that an O-ring is provided to achieve a seal between the permanent magnet and the second peripheral surface.