Rotary kinetic fluid motors or pumps – Smooth runner surface for working fluid frictional contact
Reexamination Certificate
2001-06-01
2003-09-30
Verdier, Christopher (Department: 3745)
Rotary kinetic fluid motors or pumps
Smooth runner surface for working fluid frictional contact
C415S121200, C415S143000, C415S169100, C415S055500, C415S055600, C415S055700
Reexamination Certificate
active
06626639
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to vacuum pumps and in particular, “hybrid” or compound vacuum pumps which have two or more sections with different operational modes for improving the operating range of pressures and throughput of the pumps.
In European patent application number 97302890 (EP 0 805 275 A2), there is described a compound vacuum pump having a regenerative section and a Holweck section.
A disadvantage of vacuum pumps, which consist of or include a regenerative section, is that the regenerative section is sensitive to dust and other foreign bodies. Dust and other foreign bodies have been known to cause blade breakage and erosion or occlusion within the fine running tolerances associated with regenerative sections.
OBJECT AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide a compound vacuum pump having Holweck and regenerative sections, and including a trap for preventing or inhibiting dust and other foreign bodies from reaching the inlet of the regenerative section.
According to the present invention, there is provided a compound vacuum pump consisting of a Holweck section upstream of a regenerative section, and means associated with the Holweck section for separating and trapping dust and other foreign bodies within the Holweck section.
In one embodiment, the Holweck section includes alternate stationary and rotating cylinders, the stationary cylinders being mounted on a stator and the rotating cylinders being mounted for rotary movement with a rotor; and separating and trapping means including an annular abutment formed on the radially innermost rotating cylinder.
In a further embodiment, the Holweck section includes alternate stationary and rotating cylinders, the stationary cylinders being mounted on a stator and the rotating cylinders being mounted for rotary movement with a rotor; and separating and trapping means being located between the last stage of the Holweck section and the inlet stage of the regenerative section, the separating and trapping means including a cavity formed in the Holweck stator and immediately opposite said cavity a blade fixed for rotary movement extending radially outwardly from the outermost rotating cylinder.
REFERENCES:
patent: 4323369 (1982-04-01), Monson et al.
patent: 4808067 (1989-02-01), Saulgeot
patent: 5709528 (1998-01-01), Hablanian
patent: 5921746 (1999-07-01), Yu et al.
patent: 6135709 (2000-10-01), Stones
patent: 0 129 709 (1985-01-01), None
patent: 0 805 275 (1997-11-01), None
patent: 0 805 275 (1998-07-01), None
European Search Report completed Nov. 29, 2002 of Application No. EP 01 30 4799.
Cohen Joshua L.
Pace Salvatore P.
The BOC Group plc
Verdier Christopher
Zebrak Ira Lee
LandOfFree
Vacuum pump does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vacuum pump, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vacuum pump will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3061946