Annular support for rolling bearings

• US 7,553,123 B2
• Filed: 07/19/2005
• Issued: 06/30/2009
• Est. Priority Date: 07/20/2004
• Status: Expired due to Fees

• Current Assignee: Varian, S.p.A (Agilent Technologies, Inc.)
• Original Assignee: Varian, S.p.A (Agilent Technologies, Inc.)
• Inventors: Casaro, Fausto
• Primary Examiner(s): Look; Edward
• Assistant Examiner(s): EASTMAN, AARON ROBERT
• Application Number:
  US11/184,279
• Publication Number:
  US 20060018774A1
• Time in Patent Office: 1,442 Days
• Field of Search: 415/90, 415/119, 415/229, 417/423.4, 384/99, 384/535, 384/536, 384/581, 384/582
• US Class Current: 415/90
• CPC Class Codes: F01D 25/164 Flexible supports; Vibration damping means associated with the bearing
• CPC Class Codes: F04D 19/04 specially adapted to the production of a high vacuum, e.g. molecular pumps
• CPC Class Codes: F04D 29/059 Roller bearings
• CPC Class Codes: F04D 29/668 damping or preventing mechanical vibrations
• CPC Class Codes: F16C 2360/45 Turbo-molecular pumps
• CPC Class Codes: F16C 27/04 Ball or roller bearings, e.g. with resilient rolling bodies

Abstract

A support ring (1) for rolling bearings (11), especially for rolling bearings applied to rotors with very high rotation speed, such as rotors of rotary vacuum pumps, the ring comprising a pair of concentric cylindrical shells (3, 5) connected together by a plurality of oblique radial plates (9), at least one of said shells (3, 5) being circumferentially broken so as to define a plurality of shoes (7), each shoe being connected to at least one of the radial plates (9) in such a manner as to define shoe portions or arcs (A₁, A₂) of different length, wherein the plates (9) are resilient and allow for the radial displacement of the shoes (7) so as to restrain vibrations of the rotating portion.

Claims

1. A support (1) for rolling bearings (11) comprising:

a pair of concentric cylindrical shells (3,5) connected together by a plurality of radial plates (9), at least one of said shells (3,5) being circumferentially broken by a plurality of slits (17) so as to define a plurality of shoes (7), each of said radial plates (9) being connected to a corresponding one of said shoes (7),

wherein each of said plates (9) is connected to said shells (3,5) along generatrices lying in different planes (P₁, P₂) passing through a central axis (C) of said concentric cylindrical shells (3,5) and lying in a region intermediate between the slits (17) defining said corresponding shoe (7) and is connected to said respective shoe (7) along a generatrix lying in plane (P₂) arranged so as to define shoe portions or arcs (A₁, A₂) of different lengths.

2. The support as claimed in claim 1, wherein the inner cylindrical shell (5) is circumferentially broken as to defined said plurality of shoes (7), the outer cylindrical shell (3) being solid.

3. The support as claimed in claim 1, wherein the outer cylindrical shell (3) is circumferentially broken as to define said plurality of shoes (7), the inner cylindrical shell (5) being solid.

4. The support as claimed in claim 1, wherein said plates (9) are resilient allowing a radial displacement of said shoes (7).

5. The support as claimed in claim 1, wherein the shoes of said plurality are separated by equally spaced breaks.

6. The support as claimed in claim 1, wherein the shoes of said plurality are separated by breaks, which are formed by axial slits (17) parallel to the generatrices of said cylindrical shells (3, 5).

7. The support as claimed in claim 1, wherein said planes (P₁, P₂) with generatrices are arranged so that the length of the shoe arc (A₃) extending from the line of intersection with said first plane (P₁) to an end of said shoe (7) is substantially the same as that of the shoe arc (A₂) extending from the line of intersection with said second plane (P₂) to the opposite end of said shoe (7).

8. The support as claimed in claim 1, wherein said plates (9) are substantially “

S”

shaped.

9. The support as claimed in claim 1, further comprising a resilient material which is interposed between said shells (3,5).

10. The support as claimed in claim 9, wherein said resilient material is an elastomer such as rubber or a silicone compound.

11. A rolling bearing (11) having an outer first ring (13), an inner second ring (15) and a plurality of balls or rollers interposed between said rings (13,15), comprising:

a cylindrical shell (3) concentric with said inner and outer rings and connected by means of a plurality of radial plates (9) to said first or second ring (13, 15), said shell (3) being broken by a plurality of slits (17) so as to define a plurality of shoes (7), each of said radial plates (9) being connected to one of said shoes wherein each of said plates (9) is connected to said shell (3) and to said first or second ring (13,15) along generatrices lying in different planes (P₁, P₂) passing through a central axis (C) of said rings (13,15) and lying in a region intermediate between the slits (17) defining said corresponding shoe (7) and is connected to said respective shoe (7) along a generatrix lying in plane (P₂) arranged so as to define shoe portions or arcs (A₁, A₂) of different lengths.

12. The support as claimed in claim 11, wherein said rings are made of metal.

13. The support as claimed in claim 11, wherein said ring are made of tempered steel.

14. A rotary vacuum pump comprising a rotating shaft (105) rotated by an electric motor (109) and supported by at least one rolling mechanical bearing (107a, 107b), said shaft being equipped with rotor discs (103) co-operating with stator rings for gas pumping, the pump and comprising:

a support ring (1) disposed between said rolling bearing (107a, 107b) and the corresponding seat (115) provided in said pump, and/or between said bearing (107a, 107b) and said shaft (105), said support ring comprising a pair of concentric cylindrical shells (3, 5) connected together by a plurality of radial plates (9), at least one of said shells (3, 5) being circumferentially broken so as to define a plurality of shoes (7), each of said radial plates (9) being connected to one of said shoes, wherein each of said plates (9) is connected to said shell (3) and to a first or second ring (13,15) along generatrices lying in different planes (P₁, P₂) passing through a central axis (C) of said rings (13, 15) and lying in a region intermediate between the slits (17) defining said corresponding shoe (7) and is connected to said respective shoe (7) along a generatrix lying in plane (P₂) arranged so as to define shoe portions or arcs (A₁, A₂).

15. The vacuum pump as claimed in claim 14, wherein said pump is a turbomolecular pump.