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US4351515A Expired / Lapsed US ⏱️ 0.0 years remaining

Feedback control type shock absorbing suspension system

Assignee: Toyota Motor Corp
•
Filing: 1980-06-16
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Granted: 1982-09-28
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Expires: 2000-06-16
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Abstract

Abstract A feedback control type shock absorbing suspension system is inserted between a body including a vibration source and a foundation for suspension of the body. The absorbing system includes a suspending spring mechanism. A sensor mechanism detects velocity of relative movement between the body and the foundation. A cylinder-piston mechanism includes a cylinder connected to one of the body and the foundation and a piston connected to the other of the body and the foundation. Magnetic fluid or powder is held between the inner wall of the cylinder and the outer wall of the piston. An exciting coil generates magnetic flux for magnetizing the magnetic fluid or powder. An electric circuit applies to the exciting coil a control voltage which corresponds to the detected value of the sensor mechanism. The vibration-damping force between the cylinder and the piston is controlled by magnetizing the magnetic fluid or powder.

Inventors

  • 👤 Akio Yoshida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:26
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/32; F16F9/53; F16F9/535; B; B60; B60G; B60G17/00; B60G17/015; B60G17/0152; B60G17/0157; B60G2204/00; B60G2204/10; B60G2204/11; B60G2204/112

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 224 words
A feedback control type shock absorbing suspension system to be inserted between a body including a vibration source and a foundation for suspension of said body, which system comprises a suspending spring mechanism interposed between said body and said foundation, a sensor mechanism for detecting velocity of relative movement between said body and said foundation, a cylinder-piston mechanism including a cylinder connected to one of said body and said foundation and a piston connected to the other of said body and said foundation, a magnetic fluid or powder being held between the outer wall face of the piston and the inner wall face of the cylinder, an exciting coil for generating a magnetic flux for magnetizing said magnetic fluid or powder, and an electric circuit for applying a control voltage corresponding to the detected value of said sensor mechanism to said exciting coil, wherein at least two annular seal members are arranged in axially spaced relation between the outer wall face of the piston and the inner wall face of the cylinder, the space between said seal members constituting a sealed annular chamber, said chamber being filled with all of the magnetic fluid or powder between the inner wall surfaces of the cylinder, and wherein the vibration-damping force between the cylinder and the piston is controlled by magnetization of said magnetic fluid or powder.
Claim 2
Dependent Claim 224 words
A feedback control type shock absorbing suspension system to be inserted between a body including a vibration source and a foundation for suspension of said body, which system comprises a suspending spring mechanism interposed between said body and said foundation, a sensor mechanism for detecting velocity of relative movement between said body and said foundation, a cylinder-piston mechanism including a cylinder connected to one of said body and said foundation and a piston connected to the other of said body and said foundation, a magnetic fluid or powder being held between the outer wall face of the piston and the inner wall face of the cylinder, an exciting coil for generating a magnetic flux for magnetizing said magnetic fluid or powder, and an electric circuit for applying a control voltage corresponding to the detected value of said sensor mechanism to said exciting coil, wherein at least two annular seal members are arranged in axially spaced relation between the outer wall face of the piston and the inner wall face of the cylinder, the space between said seal members constituting a sealed annular chamber, said chamber being filled with all of the magnetic fluid or powder between the inner wall surfaces of the cylinder, and wherein the vibration-damping force between the cylinder and the piston is controlled by magnetization of said magnetic fluid or powder.
Claim 3
Dependent Claim 64 words
A suspension system as set forth in claim 1, wherein the suspending spring mechanism comprises a first compression coil spring disposed between one inner end wall face of the cylinder and one end wall face of the piston and a second compression coil spring disposed between the other inner end wall face of the cylinder and the other end wall face of the piston.
Claim 4
Dependent Claim 59 words
A suspension system as set forth in claim 1, wherein the sensor mechanism for detecting velocity of relative movement comprises an annular magnet attached to a rod connected to the piston and a coil attached to the inner circumference of an annular yoke extended from one end of the cylinder, said coil being disposed adjacent to said annular magnet.
Claim 5
Dependent Claim 30 words
A suspension system as set forth in claim 1, wherein an annular magnetic core is disposed in close proximity to the periphery of the cylinder outside the sealed annular chamber.
Claim 6
Dependent Claim 32 words
A suspension system as set forth in claim 4, wherein the exciting coil for generating a magnetic flux for magnetizing the magnetic fluid is disposed in the interior of the magnetic core.
Claim 7
Dependent Claim 38 words
A suspension system as set forth in claim 5, wherein in the central portion of the sealed annular chamber, an annular magnetic flux guide groove is formed on the periphery of the piston in the circumferential direction thereof.
Claim 8
Dependent Claim 29 words
A suspension system as set forth in claim 5, wherein a non-magnetic portion for intercepting the magnetic flux is disposed between the sealed annular chamber and the exciting coil.
Claim 9
Dependent Claim 43 words
A suspension system as set forth in claim 4, wherein a plurality of fine holes extending in the radial direction and communicating with the sealed annular chamber are formed in the portion of the wall of the cylinder surrounded by the magnetic core.

References Cited (Backward Citations)

US2973969A Cited
US3084009A Cited
US3059915A Cited
US3243013A Cited
US3509742A Cited
US3840097A Cited
US4093177A Cited
US4131866A Cited
US4127835A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-09-27 1986-03-29 1986-09-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-09-27 1990-03-29 1990-09-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-09-27 1994-03-29 1994-09-28 $7700.00 Window Closed / Lapsed

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