STATOR RING FOR A TURBOMOLECULAR VACUUM PUMP

ANNEAU DE STATOR POUR POMPE A VIDE TURBOMOLECULAIRE

English Abstract

The invention relates to a stator ring (1) for a turbomolecular vacuum pump,
comprising an outer spacing ring (3) and stator blades (2). In order to reduce
fabrication and mounting costs, said spacing ring (3) and said stator blades
(2) are designed as a unitary part.

French Abstract

L'invention concerne un anneau de stator (1) conçu pour une pompe à vide turbomoléculaire, comportant un anneau d'écartement extérieure (3) et des ailettes de stator (2). Afin de diminuer les coûts de fabrication et de montage, ledit anneau d'écartement (3) et lesdites ailettes de stator (2) sont d'un seul tenant.

Claims

Page 5
Stator Ring for a Turbomolecular Vacuum Pump
CLAIMS
1. Stator ring (1) for a turbomolecular vacuum pump, comprising an outer
spacing ring (3) and stator blades (2) wherein spacing ring (3) and said
stator
blades (2) are designed as a unitary part.
2. Stator ring according to claim 1, wherein the blades (2) extend between the
outer ring (3) and an inner ring (4) which also is an integrated component of
the stator ring (1).
3. Stator ring according to claim 1 or 2, wherein it is manufactured by
milling.

Description

CA 02379547 2002-O1-16
r WO b1/1 1242 Page 1 of 6 99.012W0
Stator Ring for a Turbomolecular Vacuum Pump
The present invention relates to a stator ring for a turbomolecular vacuum
pump,
comprising an outer spacing ring and with stator blades.
The design of turbomolecular vacuum pumps resembles that of turbines. Series
of
rotor blades alternate with series of stator blades.
It is known to equip the stator and the rotor of a turbomolecular vacuum pump
each
with rings of stator and rotor blades which can be fitted separately. In this
instance
the turbomolecular vacuum pump is assembled in such a manner that one each
ring
of stator and rotor blades are positioned over each other in alternating
fashion.
Spacing rings located between the individual rings ensure that the
intermeshing
blades do not touch each other.
Gaining more and more prominence lately, is a unitary design for the rotor
with its
blades. In this instance the rings for the stator blades need to be divided so
as to be
capable of assembling the system of intermeshing series of stator and rotor
blades.
Commonly the stator rings consist of two stator half-rings which are centred
and
spaced apart by the spacing rings. From EU-A-478882 a stator designed in such
a -
manner for a turbomolecular vacuum pump is known.

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Of disadvantage in the state-of-the-art design is the relatively large number
of
components for the stator pack which have an influence on manufacturing costs
and
assembly costs.
It is the task of the present invention to reduce the complexity of
manufacturing and
assembling the stator for a turbomolecular vacuum pump.
This task is solved through the present invention in that the spacing ring and
the
stator blades within a series of stator blades are of an unitary design.
Besides the reduction in the number of parts which need to be manufactured and
assembled, the present invention offers a further significant advantage
related the
heat dissipation characteristic. In the instance of a ring of stator blades
with
integrated outer spacing ring also the number of outer contact surfaces is
reduced
compared' to the state-of-the.-art. Thus heat dissipation of the heat
dissipated by the
blades into the stator is significantly improved.
'~ Translator's note: The German text states "Verbleich" here whereas
"Vergleich" would be
appropriate. Therefore "Vergleich" has been assumed for the translation.

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Expediently the stator ring has, besides the outer integrated spacing ring
also an
inner ring integrated with the blades. Thus a highly stable system results
which may
easily be manufactured by milling, for example.
Further advantages and details of the present invention shall be explained
with
reference to the design examples depicted in drawing figures 1 to 4. Depicted
are in
- drawing figures 1 and 2 a stator half-ring according to the present
invention
intended for the intake side of a turbomolecular vacuum pump,
- drawing figures 3 and 4 a stator half-ring according to the present
invention
intended for the discharge side of a turbomolecular vacuum pump.
In all drawing figures the stator half-ring is designated as 1, the stator
blades as 2, an
outer half-ring as 3 and an inner half-ring as 4. All components are of an
unitary
design.
''~ The depicted stator half-rings2~ 1 allow the assembly of a turbomolecular
vacuum
pump with a unitary rotor. If also the rotor comprises separate rings of rotor
blades,
undivided rings of stator blades 1 may be employed. In the drawing figures
half-rings
are depicted as design examples.
Translator's note: The German text states "Statorhalbring' here whereas
"Statorhalbringe" would
be appropriate. Therefore "Statorhalbringe" has been assumed for the
translation.

CA 02379547 2002-O1-16
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The patent claims are to be understood in such a manner that a stator ring
according
to the present invention may be either divided or undivided.
The outer ring 3 has - seen from the axial direction - such a height which
allows it to
operate also as a spacing ring. The inner ring must be located between the
series of
rotor blades not depicted. Its axial height is correspondingly less.
Distance and angle of incidence for the blades 2 of the stator half-ring 1 in
accordance with drawing figures 1 and 2 are relatively great. Blade
configurations of
this kind are employed in the inlet area of a turbomolecular vacuum pump.
In the design example in accordance with drawing figures 3 and 4 both angle of
incidence and distance between the blades are relatively small. The blades
overlap
in part. Blade configurations of this kind are employed in the discharge area
of a
turbomolecular vacuum pump.

Representative Drawing