U.S. patent application number 12/529513 was filed with the patent office on 2010-05-13 for centrifugal pump comprising a spiral housing.
This patent application is currently assigned to Continental Automotive GmbH. Invention is credited to Rajko Colic.
Application Number | 20100119391 12/529513 |
Document ID | / |
Family ID | 39323949 |
Filed Date | 2010-05-13 |
United States Patent
Application |
20100119391 |
Kind Code |
A1 |
Colic; Rajko |
May 13, 2010 |
Centrifugal Pump Comprising a Spiral Housing
Abstract
The invention relates to a centrifugal pump comprising a spiral
housing consisting of a first housing part and a second housing
part, the latter being tubular and delimited in a region facing
away from the inlet E of the inflowing medium in order to receive
the rotor in its interior in a wet chamber N. A stator surrounds
the second housing part and is situated in the dry chamber T in the
vicinity of the exterior of the rotor (3). The tubular delimitation
of the second housing part is provided with a cover, a first seal
being located between the cover and the second housing part. Said
seal comes into contact with the environment on at least one side
facing away from the wet chamber N. The invention also relates to
the use of the centrifugal pump as a coolant centrifugal pump in a
motor vehicle.
Inventors: |
Colic; Rajko; (Bad Homburg,
DE) |
Correspondence
Address: |
COHEN, PONTANI, LIEBERMAN & PAVANE LLP
551 FIFTH AVENUE, SUITE 1210
NEW YORK
NY
10176
US
|
Assignee: |
Continental Automotive GmbH
Hannover
DE
|
Family ID: |
39323949 |
Appl. No.: |
12/529513 |
Filed: |
February 8, 2008 |
PCT Filed: |
February 8, 2008 |
PCT NO: |
PCT/EP08/51572 |
371 Date: |
September 1, 2009 |
Current U.S.
Class: |
417/423.14 ;
415/206 |
Current CPC
Class: |
F04D 29/628 20130101;
F04D 13/0626 20130101; F04D 29/086 20130101; F04D 29/426
20130101 |
Class at
Publication: |
417/423.14 ;
415/206 |
International
Class: |
F04D 13/06 20060101
F04D013/06; F04D 29/42 20060101 F04D029/42; F04D 29/08 20060101
F04D029/08 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 1, 2007 |
DE |
10 2007 010 051.7 |
Claims
1.-7. (canceled)
8. A centrifugal pump having a spiral housing, the centrifugal pump
comprising: a first housing part; a second housing part configured
to mate with the first housing part, a portion of the second
housing part remote from an inlet being tubular and accommodating a
rotor in an internal wet chamber; a dry chamber externally
surrounding the second housing part, the dry chamber accommodating
a stator arranged in an area corresponding to the rotor; a motor
housing externally surrounding the stator; a cover configured to
mate with the tubular portion of the second housing part; and a
first seal arranged between the cover and the tubular portion of
the second housing part.
9. The centrifugal pump as claimed in claim 8, wherein the first
seal is connected to a surrounding environment by at least one of a
duct and a passage in the cover.
10. The centrifugal pump as claimed in claim 8, further comprising
a second seal arranged between the motor housing and the tubular
portion of the second housing part.
11. The centrifugal pump as claimed in claim 8, wherein the first
seal is an O-ring seal.
12. The centrifugal pump as claimed in claim 8, wherein the second
housing part comprises a first bearing and the cover comprises a
second bearing, the first and second bearings are configured for
rotatable mounting of the rotor.
13. The centrifugal pump as claimed in claim 8, wherein an outer
area of the second housing part has an outline of curved
longitudinal section perpendicular to a direction of flow of a
medium flowing in from the inlet.
14. The centrifugal pump as claimed in claim 8, wherein the
centrifugal pump is configured as a coolant centrifugal pump in a
motor vehicle.
15. The centrifugal pump as claimed in claim 8, wherein the first
seal is connected to a surrounding environment by at least one of a
duct and a passage on the cover.
16. The centrifugal pump as claimed in claim 10, wherein the second
seal an O-ring seal.
17. The centrifugal pump as claimed in claim 16, wherein the second
housing part comprises a first bearing and the cover comprises a
second bearing, the first and second bearings configured for
rotatable mounting of the rotor.
18. The centrifugal pump as claimed in claim 10, wherein the first
seal and the second seal are arranged at opposing respective
internal and external areas of the tubular portion of the second
housing part.
Description
[0001] The invention relates to a centrifugal pump having a spiral
housing. The invention further relates to the use of the
centrifugal pump. Centrifugal pumps having spiral housings are
known. DE 103 47 302 A1 describes a two-part spiral housing for a
centrifugal pump, which is of optimized design from the point of
view of fluid mechanics. Such centrifugal pumps are generally
driven by an electric motor, the stator of the electric motor being
arranged in a dry chamber and the rotor in a wet chamber. The rotor
therefore turns in the wet chamber, flowing around which is the
medium to be pumped. The dry chamber and the wet chamber are here
divided by a separately arranged can, the disadvantage being that
it is necessary to arrange sealing elements between the one part of
the spiral housing and the can in order to avoid liquid or vapor
from the wet chamber getting into the dry chamber. Over prolonged
operating times, that is to say as the seal gradually becomes
porous, or when subjected to vibrations acting on the centrifugal
pump, it is often not possible to avoid larger quantities of liquid
getting into the dry chamber and flooding it. This then results in
more serious damage to the stator and to electronic components,
which in addition to the stator are also situated in the dry
chamber.
[0002] The object of the invention, therefore, is to create a
centrifugal pump having a spiral housing, in which liquid from the
wet chamber enclosing the rotor is entirely prevented from entering
the dry chamber, and consequently flooding the dry chamber.
[0003] The object of the invention is achieved by a centrifugal
pump having a spiral housing, which comprises a first housing part
and a second housing part, the area of the second housing part
remote from the inlet E of the inflowing medium being of tubular
design and its outline delimited for internal accommodation of the
rotor in the wet chamber N, a stator being arranged in the dry
chamber T externally surrounding the second housing part in the
area of the rotor, wherein a cover is arranged on the tubular
outline of the second housing part, a first seal, which is
connected to the surroundings on at least one side remote from the
wet chamber N, being arranged between the cover and the second
housing part. The area of the second housing part remote from the
inlet E of the inflowing medium is of tubular design and therefore
assumes the function of a can, the additional separate arrangement
of which, however, can be completely dispensed with. The first seal
is connected to the surroundings on at least one side remote from
the wet chamber N. This means that at least one part of the seal is
in direct contact with the surrounding air, or that if the need
arises a liquid flowing out via the seal can pass directly into the
surroundings. It has surprisingly emerged that in this way it is
possible to entirely prevent liquid from the wet chamber N getting
into the dry chamber T, and thereby to prevent flooding of the dry
chamber T. The connection of the first seal to the surroundings
advantageously ensures that should the first seal start to
decompose after prolonged operating times, some of the liquid can
be released directly into the surroundings and therefore does not
get into the dry chamber T. In this way damage to the stator and
damage to other electrical components in the dry chamber T can
advantageously be avoided.
[0004] In a preferred development of the invention the first seal
is connected to the surroundings by ducts or passages in or on the
cover. This represents a relatively easy and straightforward way of
connecting the first seal to the surroundings, which allows the
advantageous use of various sealing elements as first seal.
[0005] In a further preferred development of the invention the
stator is externally surrounded by a motor housing, and a second
seal is arranged between the motor housing and the second housing
part in the area of its tubular outline. This advantageously serves
to prevent even slight quantities of vapor getting into the dry
chamber T. This measure therefore advantageously serves to keep the
dry chamber T absolutely dry. This is of advantage particularly
where the flowing medium contains corrosive constituents.
[0006] In a further preferred development of the invention an
O-ring seal is in each case provided as first seal and as second
seal. It may be advantageous here to arrange the first seal and the
second seal in the form of an O-ring directly opposite on the
second housing part, although this is not absolutely essential. The
first seal in the form of an O-ring is then arranged on the inside
wall of the tubular outline of the second housing part. The second
seal is then arranged in the form of an O-ring on the outside wall
of the tubular outline of the second housing part. This measure
facilitates the manufacture of the centrifugal pump.
[0007] In a further preferred development of the invention the
second housing part comprises a first bearing and the cover
comprises a second bearing for rotatable mounting of the rotor. The
cover may in this case itself form the second bearing, or it merely
serves to accommodate such a bearing. It is advantageous here that
the additional arrangement of a special bearing race inside the
centrifugal pump can be dispensed with.
[0008] In a further preferred development of the invention the
outer area of the second housing part has an outline of curved
longitudinal section perpendicular to the direction of flow of the
medium flowing in from the inlet E. The precise profile of the
curved outline is in this case of an engineered design to optimize
the fluid mechanics. This is an especially advantageous way of
minimizing the overall space required for the centrifugal pump.
[0009] The invention finally relates to the use of the centrifugal
pump as a coolant centrifugal pump in a motor vehicle. Coolant
centrifugal pumps in motor vehicles have to function perfectly over
prolonged operating times, there being an absolute need to avoid
flooding of the dry chamber T. The use of the centrifugal pump as a
coolant centrifugal pump in a motor vehicle is therefore
particularly advantageous.
[0010] The invention will be explained in more detail below by way
of example and with reference to the drawing (FIG. 1 to FIG.
3).
[0011] FIG. 1 shows a longitudinal, three-dimensional section
through the centrifugal pump.
[0012] FIG. 2 shows a longitudinal, three-dimensional section
through the centrifugal pump in the form of an exploded
diagram.
[0013] FIG. 3 shows a longitudinal, three-dimensional section
through a centrifugal pump according to the state of the art.
[0014] FIG. 1 shows a centrifugal pump in longitudinal,
three-dimensional section. The centrifugal pump comprises a spiral
housing, which comprises a first housing part 1 and a second
housing part 2, the area of the second housing part 2 remote from
the inlet E of the inflowing medium being of tubular design and its
outline delimited for internal accommodation of the rotor 3 in the
wet chamber N. The flowing medium is here illustrated by the bold
arrow. A stator 4 is arranged in the dry chamber T externally
surrounding the second housing part 2 in the area of the rotor 3. A
cover 5 is arranged on the tubular outline of the second housing
part 2, a first seal 6, which is connected to the surroundings on
at least one side remote from the wet chamber N, being arranged
between the cover 5 and the second housing part 2. The first seal 6
is here connected to the surroundings by ducts 5' on the cover 5.
The stator 4 is externally surrounded by a motor housing 7. A
second seal 8 is arranged between the motor housing 7 and the
second housing part 2 in the area of its tubular outline. The first
seal 6 and the second seal 8 are each provided in the form of an
O-ring seal. The second housing part 2 has a first bearing 2* and
the cover 5 has a second bearing 5* for rotatable mounting of rotor
3. This makes it possible to dispense entirely with an additional
bearing race. The outer area of the second housing part 2 has an
outline 2** of curved longitudinal section perpendicular to the
direction of flow of the medium flowing in from the inlet E. If the
first seal 6 becomes porous after prolonged operating times, for
example, the liquid passes via the first seal 6 into the ducts 5',
which constitute the connection to the surroundings. The liquid is
therefore given off directly to the surroundings, which is
illustrated by the light arrow. This makes it impossible for liquid
to pass from the wet chamber N, in which the rotor 3 is arranged,
into the dry chamber T, so that flooding of the dry chamber T is
entirely prevented. The arrangement of the second seal 8 also
serves to prevent slight traces of escaping vapor getting into the
dry chamber T, which is especially advantageous where the liquid
contains corrosive fractions. This therefore makes it possible to
keep the dry chamber T completely dry.
[0015] FIG. 2 shows the centrifugal pump in longitudinal,
three-dimensional section in the form of an exploded diagram. In
one area the second housing part 2 is of tubular design and its
outline delineated for internal accommodation of the rotor 3. The
first seal 6 and the second seal 8 are in each case embodied as
O-ring seals.
[0016] FIG. 3 shows a longitudinal, three dimensional section
through a centrifugal pump according to the state of the art. The
centrifugal pump according to the state of the art has a spiral
housing, which comprises a first housing part 1b and a second
housing part 2b. Liquid medium to be pumped, represented by the
bold arrow, passes through the inlet Eb into the wet chamber Nb, in
which the rotor 3b is rotatably mounted. A stator 4b is externally
arranged in the dry chamber Tb in the area of the rotor 3b. The dry
chamber Tb is here closed off from the surroundings by a motor
housing 7b. In the state of the art the wet chamber Nb is separated
from the dry chamber Tb by the disadvantageous arrangement of a can
9b, it being possible under certain circumstances for liquid to get
into the dry chamber Tb from the wet chamber Nb owing to a
disadvantageous arrangement of a sealing ring 10b, which has to be
arranged between the can 9b and the second housing part 2b. This
then results in a disadvantageous flooding of the dry chamber Tb,
which may happen, for example, if the centrifugal pump is subjected
to heavier vibrations in operation. The possible ingress of liquid
into the dry chamber Tb is illustrated by the light arrow. The
possible flooding of the dry chamber Tb results directly in damage
to the stator 4b and other electronic components (not shown), which
is prevented by the centrifugal pump according to the
invention.
* * * * *