PL185488B1 - Ferromagnetic seal for rolling bearings - Google Patents

Abstract

Ferromagnetic seal for rolling bearings, comprising a permanent magnet, multi-edge pole shoes and a ferromagnetic liquid located in the gaps formed between the pole shoe and the shaft, characterized in that a seal housing (3) made of a non-magnetic material is located between the shaft (1) and the housing (2) of the device, in which an axially polarized permanent magnet (4) is fixedly mounted, adjacent to a multi-edge radial pole shoe (5), placed between the housing (3) and the shaft (1), adjacent to a lip sealing ring (6), wherein on the opposite side of the magnet (4) there is a multi-edge axial pole shoe (7) located, adjacent to a slip ring (8) mounted in the housing (3), and the multi-edge radial pole shoe (5) and the multi-edge axial pole shoe (7) are made of a magnetic material, wherein under a permanent magnet (4), a spacer sleeve (9) is placed between the radial pole piece (5) and the axial pole piece (7) and a ferromagnetic fluid (10) is additionally placed in the gaps between the axial pole piece (7) and the permanent magnet (4)

Description

The subject of the invention is a ferromagnetic seal for rolling bearings used as a protective seal for rolling bearings in devices requiring high operational reliability, such as, for example, computer disk memory drives.

Known from the book "Magnitnyje żidkosti w Maszinostrojenije", Wydawnictwo Maszinostrojenije, Moscow 1993, page 54, fig. 4.8, ferromagnetic sealing for rolling bearings has between the body and the shaft of the device an insert made of non-magnetic material adjacent to the bearing, in which a permanent magnet is embedded axially polarized located between the pole pieces. The ferromagnetic liquid is held by the magnetic field forces in the gaps between the pole pieces and the shaft.

The essence of the seal according to the invention containing a permanent magnet, multi-edge pole pieces and a ferromagnetic liquid located in the gaps formed between the pole piece and the shaft is that between the shaft and the housing of the device there is a seal holder made of non-magnetic material, in which an axially polarized permanent magnet is immobile and adjacent to a multi-edge radial pole piece between the housing and shaft, and adjacent to a lip seal. On the opposite side of the magnet there is a multi-edged axial pole piece adjacent to the slip ring embedded in the housing. The multi-edge radial pole piece and the multi-edge axial pole piece are made of a magnetic material, with a spacer sleeve placed under the permanent magnet between the radial pole piece and the axial pole piece. The ferromagnetic liquid is additionally located in the gaps between the axial pole piece and the permanent magnet.

The seal according to the invention is characterized by a compact structure and high operational reliability thanks to the use of a ferromagnetic seal and a lip ring built into the housing. The lip sealing ring embedded in the seal housing provides additional protection against the ingress of dirt.

The subject of the invention is shown in the embodiment on the drawing showing a ferromagnetic seal for rolling bearings in a vertical section.

185 488

The seal according to the invention has between the shaft 1 and the housing 2 of the device a seal housing 3, made of non-magnetic material, in which a permanent magnet 4 axially polarized and adjacent to a multi-edge radial pole piece 5 placed between the housing 3 and the shaft 1 and adjacent to On the opposite side of the magnet 4 there is a multi-edge axial pole piece 7 adjacent to a slip ring 8 seated in the housing 3. The multi-edge radial pole piece 5 and the multi-edge axial pole piece 7 are made of magnetic material. Under the permanent magnet 4, between the radial pole piece 5 and the axial pole piece 7 is a spacer sleeve 9. In the gaps formed between the pole piece 5 and the shaft 1 and between the pole piece 7 and the permanent magnet 4 there is a ferromagnetic liquid 10.

The closed magnetic circuit is formed by a permanent magnet 4, a radial pole 5, an axial pole 7, a ferromagnetic fluid 10 and a shaft 1.

Under the operating conditions of the seal, the magnetic field forces generated by the permanent magnet 4 keep the ferromagnetic fluid. 10 in the gaps between the radial pole piece 5 and the shaft 1 and between the axial pole piece 7 and the permanent magnet 4, thus ensuring tightness. The lip sealing ring 6 embedded in the housing 3 increases the effectiveness of the seal.

185 488

Publishing Department of the UP RP. Mintage 60 copies. Price PLN 2.00.

Claims (1)

Patent claim Ferromagnetic seal for rolling bearings, containing a permanent magnet, multi-edge pole pieces and a ferromagnetic liquid located in the gaps formed between the pole piece and the shaft, characterized in that between the shaft (1) and the housing (2) of the device there is a seal housing (3) made of non-magnetic material , in which a permanent magnet (4), axially polarized, is immobile, adjacent to a multi-edge radial pole piece (5), placed between the housing (3) and the shaft (1), adjacent to the sealing lip ring (6), on the opposite side of the magnet ( 4) there is a multi-edged axial pole piece (7) adjacent to the slip ring (8) embedded in the housing (3), and the multi-edge radial pole piece (5) and the multi-edge axial pole piece (7) are made of magnetic material, and under the permanent magnet (4) between the radial pole (5) and the axial pole (7), there is a distance sleeve (9) and the ferromagnetic liquid (10) is additionally located in the gaps between the axial pole (7) and the permanent magnet (4).