IP Library Granted Patent US 7,219,781
Granted Patent B2
US 7,219,781 · App. 10/784,960 · Granted May 22, 2007

Electromagnetic suspension system

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Quick Facts
Patent No.
US 7,219,781
App. No.
10/784,960
Granted
May 22, 2007
Kind
B2
Abstract

An electromagnetic suspension system comprises a universal joint mechanism for permitting radial movement of a cylinder relative to a center yoke while preventing axial movement of the cylinder relative to the center yoke. Since the cylinder is capable of radial movement relative to the center yoke, if a lateral force acts on the cylinder, the lateral force acting on a hydraulic damper does not have any significant effect on the center yoke 17 with respect to radial movement or rocking movement thereof. Therefore, excessive sliding friction does not occur in a center-yoke dry metal and a piston-rod dry metal, thereby ensuring smooth axial relative displacement between the center yoke and an outer yoke.

Claims (42)

1. An electromagnetic suspension system comprising:

an extensible member including a cylinder and a rod capable of displacement relative to the cylinder in the axial direction of the cylinder;

a first cylindrical member connected to the rod so as to be prevented from moving relative to the axial direction of the rod, either one of a coil member and a magnetic member being provided in the first cylindrical member; and

a second cylindrical member connected to the cylinder so as to be prevented from moving relative to the axial direction of the cylinder, the other of the coil member and the magnetic member being provided in the second cylindrical member, the second cylindrical member facing either one of an inner side and an outer side of the first cylindrical member, and the second cylindrical member being slidable relative to one of the inner side and the outer side of the first cylindrical member and guided thereby;

wherein the first cylindrical member and the second cylindrical member are arranged to obtain at least one of:

the first cylindrical member being capable of radial movement or rocking movement relative to the rod; and

the second cylindrical member being capable of radial movement or rocking movement relative to the cylinder.

2. An electromagnetic suspension system according to claim 1 ,

wherein the second cylindrical member is provided in such a manner as to permit radial movement thereof relative to the cylinder while preventing axial movement thereof relative to the cylinder.

3. An electromagnetic suspension system according to claim 1 , wherein a bearing member for guiding sliding movement of the first cylindrical member and the second cylindrical member is provided between the first cylindrical member and the second cylindrical member.

4. An electromagnetic suspension system according to claim 3 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the cylinder and the second cylindrical member.

5. An electromagnetic suspension system according to claim 1 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the cylinder and the second cylindrical member.

6. An electromagnetic suspension system according to claim 1 ,

wherein the second cylindrical member is provided in such a manner as to permit radial movement thereof relative to the cylinder while preventing axial movement thereof relative to the cylinder

and wherein the first cylindrical member is provided in such a manner as to permit radial movement thereof relative to the rod while preventing axial movement thereof relative to the rod.

7. An electromagnetic suspension system according to claim 6 , wherein universal joint mechanisms for permitting the radial movement while preventing the axial movement are respectively provided between the cylinder and the second cylindrical member and between the rod and the first cylindrical member.

8. An electromagnetic suspension system according to claim 6 , wherein a bearing member for guiding sliding movement of the first cylindrical member and the second cylindrical member is provided between the first cylindrical member and the second cylindrical member.

9. An electromagnetic suspension system according to claim 8 , wherein universal joint mechanisms for permitting the radial movement while preventing the axial movement are respectively provided between the cylinder and the second cylindrical member and between the rod and the first cylindrical member.

10. An electromagnetic suspension system according to claim 1 , further comprising:

a rod guide provided in the cylinder and adapted to guide displacement of the rod;

a spherical bearing provided on an outer circumferential surface of the rod guide;

wherein the second cylindrical member is guided by the spherical bearing so that it is capable of performing rocking movement, thereby substantially uniformly maintaining a radial gap between the first cylindrical member and the second cylindrical member.

11. An electromagnetic suspension system according to claim 10 , wherein a bearing member for guiding sliding movement of the first cylindrical member and the second cylindrical member is provided between the first cylindrical member and the second cylindrical member.

12. An electromagnetic suspension system according to claim 11 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the rod and the first cylindrical member.

13. An electromagnetic suspension system according to claim 10 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the rod and the first cylindrical member.

14. An electromagnetic suspension system according to claim 1 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the rod and the first cylindrical member.

15. An electromagnetic suspension system according to claim 1 , wherein a bearing member for guiding sliding movement of the first cylindrical member and the second cylindrical member is provided between the first cylindrical member and the second cylindrical member.

16. An electromagnetic suspension system according to claim 15 , wherein a universal joint mechanism for permitting the radial movement while preventing the axial movement is provided between the rod and the first cylindrical member.

17. An electromagnetic suspension system according to claim 1 , wherein the second cylindrical member is provided in such a manner as to be capable of performing rocking movement relative to the cylinder.

18. An electromagnetic suspension device according to claim 1 , further comprising a universal joint mechanism including:

a collar provided on the rod, the collar having a flange at one end thereof;

an end of the first cylindrical member, the end including an opening through which the rod extends; and

a shoulder portion formed on the rod,

wherein the end of the first cylindrical member is held between the flange and the shoulder portion, thereby permitting radial movement of the first cylindrical member relative to the rod while restricting axial movement thereof.

19. An electromagnetic suspension system comprising:

an extensible member including a cylinder and a rod capable of displacement relative to the cylinder in the axial direction of the cylinder;

a first cylindrical member connected to the rod so as to be prevented from moving relative to the rod in the axial direction of the rod, either one of a coil member and a magnetic member being provided in the first cylindrical member; and

a second cylindrical member connected to the cylinder so as to be prevented from moving relative to the cylinder in the axial direction of the cylinder, the other of the coil member and the magnetic member being provided in the second cylindrical member, the second cylindrical member facing either one of an inner side and an outer side of the first cylindrical member, the second cylindrical member being slidable relative to one of the inner side and the outer side of the first cylinder member and being guided thereby; and

means for permitting at least one of:

(a) radial or rocking movement of the first cylindrical member relative to the rod, and

(b) radial or rocking movement of the second cylindrical member relative to the cylinder;

wherein said means comprises a connection that allows substantial radial or rocking movement but substantially no axial movement of at least one of the first cylindrical member relative to the rod and the second cylindrical member relative to the cylinder.

Assignments (4)
DEMERGER Recorded Jan 13, 2022
From: HITACHI, LTD.
To: HITACHI AUTOMOTIVE SYSTEMS, LTD.
Reel/Frame 058744/0813 →
CHANGE OF NAME Recorded Jan 13, 2022
From: HITACHI AUTOMOTIVE SYSTEMS, LTD.
To: HITACHI ASTEMO, LTD.
Reel/Frame 058758/0776 →
MERGER Recorded Mar 14, 2005
From: TOKICO LTD.
To: KABUSHIKI KAISHA HITACHI SEISAKUSHO (D/B/A HITACHI, LTD.)
Reel/Frame 016353/0831 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 30, 2004
From: AKAMI, YUSUKE; UTSUMI, NORIYUKI; YOSHIKURA, HIROSHI; CHIKUMA, HIROSHI; OHSAWA, SATOSHI
To: TOKICO LTD.
Reel/Frame 015858/0020 →