Turbomolecular pump lubricant supply systems

Patent metadata

Field	Value
Publication number	US-11111927-B2
Application number	US-201716322818-A
Country	US
Kind code	B2
Filing date	Jul 31, 2017
Priority date	Aug 4, 2016
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

A turbomolecular pump has a housing, a rotor shaft supported by a plurality of bearings for rotation relative to the housing about an axis of rotation, a deflector, a lubricant supply system and a lubricant transfer device provided on the rotor shaft. The bearings include a rolling bearing that receives lubricant from the lubricant supply system to via the lubricant transfer device. The rolling bearing is disposed intermediate the lubricant transfer device and the deflector and the deflector is configured to deflect lubricant that passes through the rolling bearing outwardly with respect to the rotor shaft.

First claim

The invention claimed is:

1. A turbomolecular pump comprising:
a housing;
a pumping mechanism disposed in said housing, said pumping mechanism comprising a rotor shaft having an axis of rotation;
a plurality of bearings supporting said rotor shaft for rotation relative to said housing about said axis of rotation, said plurality of bearings including a rolling bearing;
a deflector;
a lubricant supply system; and
a lubricant transfer device provided on said rotor shaft to transfer lubricant from said lubricant supply system to said rolling bearing,
wherein said rolling bearing is disposed intermediate said lubricant transfer device and said deflector and said deflector is configured to deflect lubricant that passes through said rolling bearing outwardly with respect to said rotor shaft;
wherein said rotor shaft extends through a bore provided in a partition disposed in said housing, and said bore is disposed between said deflector and said pumping mechanism and is defined by a bore wall;
wherein said deflector comprises an upstream major surface that faces said rolling bearing, said upstream major surface comprising a surface that is inclined with respect to said axis of rotation;
wherein said deflector comprises a downstream major surface that faces away from said rolling bearing and a drip former that is configured to cause lubricant to form into droplets that drip from said deflector to prevent lubricant flowing over said downstream major surface to said rotor shaft;
wherein said drip former comprises a circumferentially extending skirt disposed on said downstream major surface;
the turbomolecular pump further comprising an annular collection channel having an inner circumference defining an upstream end of the annular collection channel and wherein said deflector is configured to deflect said lubricant into said annular collection channel, and said drip former is positioned so that droplets drip into said annular collection channel wherein said bore wall is disposed a first radial distance from the axis of rotation, said upstream end is disposed a second radial distance from said axis of rotation, and said deflector has an outer periphery disposed a third radial distance from said axis of rotation and wherein said second radial distance is greater than said first radial distance and said third radial distance is equal to or greater than said second radial distance.

2. The turbomolecular pump as claimed in claim 1 , wherein said deflector is made of a polymer.

3. The turbomolecular pump as claimed in claim 1 , wherein said deflector is mounted on said rotor shaft.

4. The turbomolecular pump as claimed in claim 3 , wherein said deflector has a bore that receives a mating portion of said rotor shaft and is provided with at least one cut out to provide flexure adjacent said bore.

5. The turbomolecular pump as claimed in claim 1 , wherein said lubricant supply system comprises a lubricant reservoir body, a finger projecting inwardly from said reservoir body to engage said lubricant transfer device and a lubricant return member extending from said lubricant reservoir body to said collection channel to transfer lubricant from said collection channel to said lubricant reservoir body.

6. The turbomolecular pump as claimed in claim 5 , wherein said lubricant supply system further comprises an absorbent collector body disposed in said collection channel and in engagement with said lubricant return member.

7. The turbomolecular pump as claimed in claim 5 , wherein said finger and said lubricant return member are connected by an integral body member.

8. The turbomolecular pump as claimed in claim 7 , wherein said body member is a planar body having a first major face and a second major face and said reservoir body engages at least one said major face.

9. The turbomolecular pump as claimed in claim 5 , further comprising a holder having a main holder body to hold said lubricant reservoir body and a return member holder body extending from said main holder body to hold said lubricant return member, said lubricant return member extending through an aperture provided in said main holder body.

Assignees

• Edwards Ltd

Inventors

• Perrino Nicola

Classifications

• F04D29/063 Primary

  specially adapted for elastic fluid pumps · CPC title

• F04D29/002

  especially adapted for elastic fluid pumps · CPC title

• F04D19/042 Primary

  Turbomolecular vacuum pumps · CPC title

• F16C33/6685

  Details of collecting or draining, e.g. returning the liquid to a sump · CPC title

• F16N7/12

  with feed by capillary action, e.g. by wicks · CPC title