Chain unit sealed and lubricated with magnetic fluid and chain having same

Patent metadata

Field	Value
Publication number	US-11353088-B2
Application number	US-202117507520-A
Country	US
Kind code	B2
Filing date	Oct 21, 2021
Priority date	Oct 28, 2020
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

A chain unit lubricated and sealed with magnetic fluid includes a pin shaft, a magnetic sleeve, a first pole piece and a second pole piece. The sleeve is fitted over an outer periphery of the pin shaft. Both ends of the pin shaft protrude from the sleeve. A first gap exists between an inner peripheral surface of the sleeve and an outer peripheral surface of the pin shaft. The first pole piece is arranged at one of the sleeve and has a first mating hole. A second gap exists between an inner wall surface of the first mating hole and the outer peripheral surface of the pin shaft. The second pole piece is arranged at the other end of the sleeve and has a second mating hole. A third gap exists between an inner wall surface of the second mating hole and the outer peripheral surface of the pin shaft.

First claim

What is claimed is:

1. A chain unit lubricated and sealed with magnetic fluid, comprising:
a pin shaft;
a magnetic sleeve fitted over an outer periphery of the pin shaft, both ends of the pin shaft protruding from the sleeve, and a first gap being formed between an inner peripheral surface of the sleeve and an outer peripheral surface of the pin shaft;
a first inner plate having a first through-hole, one end of the sleeve being fitted and connected in the first through-hole;
a second inner plate having a second through-hole, the other end of the sleeve being fitted and connected in the second through-hole;
a first pole piece arranged at one of the sleeve and having a first mating hole, one end of the pin shaft passing through the first pole piece via the first mating hole, and a second gap being formed between an inner wall surface of the first mating hole and the outer peripheral surface of the pin shaft; and
a second pole piece arranged at the other end of the sleeve and having a second mating hole, the other end of the pin shaft passing through the second pole piece via the second mating hole, and a third gap being formed between an inner wall surface of the second mating hole and the outer peripheral surface of the pin shaft,
wherein the third gap is in communication with the first gap and the first gap is in communication with the second gap to form a cavity, and the magnetic fluid is filled in the cavity.

2. The chain unit according to claim 1 , further comprising a roller fitted over an outer periphery of the sleeve,
wherein:
a fourth gap is formed between an inner peripheral surface of the roller and an outer peripheral surface of the sleeve, and the magnetic fluid is filled in the fourth gap; and
the roller and the first pole piece are spaced apart from each other in a length direction of the pin shaft, and the roller and the second pole piece are spaced apart from each other in the length direction of the pin shaft.

3. The chain unit according to claim 2 , a wherein the first inner plate and the second inner plate arranged opposite to each other and spaced apart from each other along the length direction of the pin shaft; and,
the first inner plate and the second inner plate are arranged between the first pole piece and the second pole piece, the first inner plate adhering to the first pole piece, and the second inner plate adhering to the second pole piece.

4. The chain unit according to claim 3 , further comprising:
a first outer plate arranged on a side of the first pole piece away from the first inner plate, and having a third through-hole; and
a second outer plate arranged on a side of the second pole piece away from the second inner plate, and having a fourth through-hole;
wherein one end of the pin shaft passes through the first outer plate via the third through-hole, and the other end of the pin shaft passes through the second outer plate via the fourth through-hole.

5. The chain unit according to claim 4 , further comprising:
a first connection member connecting the first inner plate with the first pole piece; and
a second connection member connecting the second inner plate with the second pole piece.

6. The chain unit according to claim 5 , wherein:
the first pole piece has a first connection hole extending along a thickness direction of the first pole piece, the first inner plate has a second connection hole extending along a thickness direction of the first inner plate, and the first connection hole is opposite to the second connection hole, one end of the first connection member being fitted in the first connection hole, and the other end of the first connection member being fitted in the second connection hole; and
the second pole piece has a third connection hole extending along a thickness direction of the second pole piece, the second inner plate has a fourth connection hole extending along a thickness direction of the second inner plate, and the third connection hole is opposite to the fourth connection hole, one end of the second connection member being fitted in the third connection hole, and the other end of the second connection member being fitted in the fourth connection hole.

7. The chain unit according to claim 5 , wherein the first inner plate, the second inner plate, the roller, the first connection member, the second connection member, the first outer plate, and the second outer plate are all made of magnetically non-conductive materials.

8. The chain unit according to claim 1 , wherein the first pole piece, the second pole piece, and the pin shaft are all made of magnetically conductive materials.

9. The chain unit according to claim 1 , wherein the sleeve is made of a permanent magnet material.

10. A chain comprising a plurality of chain units connected in sequence, wherein the plurality of chain units are lubricated and sealed with magnetic fluid, and each of the plurality of chain units comprises:
a pin shaft;
a magnetic sleeve fitted over an outer periphery of the pin shaft, both ends of the pin shaft protruding from the sleeve, and a first gap being formed between an inner peripheral surface of the sleeve and an outer peripheral surface of the pin shaft;
a first inner plate having a first through-hole, one end of the sleeve being fitted and connected in the first through-hole;
a second inner plate having a second through-hole, the other end of the sleeve being fitted and connected in the second through-hole;
a first pole piece arranged at one of the sleeve and having a first mating hole, one of the pin shaft passing through the first pole piece via the first mating hole, and a second gap being formed between an inner wall surface of the first mating hole and the outer peripheral surface of the pin shaft; and
a second pole piece arranged at the other end of the sleeve and having a second mating hole, the other end of the pin shaft passing through the second pole piece via the second mating hole, and a third gap being formed between an inner wall surface of the second mating hole and the outer peripheral surface of the pin shaft,
wherein the third gap is in communication with the first gap and the first gap is in communication with the second gap to form a cavity, and the magnetic fluid is filled in the cavity.

Assignees

• Univ Tsinghua

Inventors

• Li Decai
• Li Yanwen
• Chen Siyu

Classifications

• F16J15/43 Primary

  kept in sealing position by magnetic force · CPC title

• F16G13/06 Primary

  with links connected by parallel driving-pins with or without rollers {so-called open links} · CPC title

• F16G15/12

  Chain links · CPC title