Note: Descriptions are shown in the official language in which they were submitted.
~ 7~P~ ~
A Spiral Housing Made of Sheet Metal
The invention relates to a spiral housing according
to the preamble of the main claim.
Spiral housings are frequently used for centrifugal
pumps of the radial and semi-axial type. Such housings may be
readily produced in a cast form; housirlgs made of sheet metal
render manufacture more difficult. Owing to deep drawing
methods, which predominate in sheet metal manufacturin~
technology, it is hardly possible to form spring housin~s
which extend in the radial direction and have a cross section
which increases over the periphery. One way of overcoming
this difficulty is illustrated in the German patent
publication 2,047,501 A, in the case of which the impeller of
a centrifugal pump is followed on the downstream side by a
housing with a simply produced annular chamber. A hollsing
cover arranged on the delivery side has a spiral configuration
extending in the axial direction so that when assembly is
completed there is a spiral chamher whose cross section varies
along the axis. However this design represents a compromise
whose effectiveness is hardly comparahle with a radially
extending spiral configuration. Particularly in the case of
impellers with a high specific speed of rotation it has becomt?
clear that pUIllp housings with radially exten(ling spirals have
distinct hydraulic advantagt?s.
A further possihle tdesign is illustratt?d in the
German patent puhlication 3,00~,672 ~ in the case of which a
spiral manufactured from pipe is inserted into an annular
chamber housiny in such a manner that a spiral chamber is
defined within the annular housing. Support elements connect
-- 2
~q,, '~5~ 3
the spiral chamber with the surrounding sealed annular chamber
housing. This type of construction requires a large amount of
material and its manufacture is an involved process.
The German patent publication 1,892,493 U has a
spiral housing, which consists of two housing halves, which in
plan view are semicircular, have different radiuses and are
offset by the difference between their radiuses. There is a
welded joint at the abutting edges. When the impeller is
suitably fitted a spiral chamber is produced.
One object of the invention is to provide a spiral
housing for a centrifugal pump made of non-machined components
and able to be produced in a simple manner. This object is
achieved in accordance with the characterizing part of the
main claim.
It is therefore possible to provide a spiral chamber
in the form of a separate component and having a uniform
internal diameter, which renders it possihle to apply the
chamber to a pump housing which for instance is in the form of
a drawn can~ and to secure it at the outlet from the impeller.
For this purpose there are further developments of the
invention in accordance with which in a housing part opposite
to the outlet of the impeller the pump housing is provided
with one or more openings and the spiral chamber covers over
such openings and is sealingly connected with the pump housing
and furthermore the spiral chamber is fitted around the pump
housing.
In accordance with a further development of the
invention the spiral chamber is arranged between two pump
housing components located on both sides of the impeller and
is sealingly connected with the same.
In this respect the pump housing may be in the form
of a can or bell housing with or without molded on connections
and may be divided upstream or downstream from the plane of
the impeller by a cutting operation in two parts. The
mutually adjacent cuts in the can housing may then be
connected in a conventional manner with the side walls which
extend in the radial direction, of the spiral housing.
Claims 5 to 8 recite embodiments which relate to the
manufacture of the spiral chamber. The spiral chamber can be
lU placed around the actual pump housing in the form of a unitary
or multipartite, belt-shaped structural component. And claims
9 to 12 relate to the design of the pump housing.
At the spiral chamber the parts of the housing on
the intake and delivery sides are connected with each other by
axially extending ribs. Furthermore it is possible for the
ribs to be in the form of independent components arranged with
a distribution over the periphery of the housing and so as to
connect the parts of the housing on the intake and delivery
sides. It is furthermore possible for the ribs to be
components of a single-piece pump housing having housing parts
on the intake and delivery sides. The ribs may also define an
intermediate chamber between a plurality of stamped openinys
for the passaye of the fluid being pumped. In order to
improve guidance of the flow it i5 possible for the ribs to be
set at an angle of attack in relation to a tanyent to the
periphery as noted.
Working embodiments of the invention are described
in the following account with reference to the figures.
Figures 1 and 2
illustrate sections taken along the
2 ~ 5~
longitudinal axis of spiral housings.
Figure 3 is a section taken transversely to the
axis of rotation through the spiral
housing.
Figures 4 through 9
illustrate different embodiments of the
invention in the form of joins of the purnp
housing at the spiral chamber.
Figure 1 illustrates a spiral housing in section.
In the illustrated working embodiment this housing consists of
a pump housing part 1 on the intake sicle on which a delivery
connection 2 is also formed. For connection with a pipe the
intake connection 2 has a connection flange 3. A pump housing
part 4 on the delivery side is provided with further flange
surfaces S for connection with a bearing support, not
illustrated here, a block motor or the like. The pump housing
parts 1 and 4 on the intake and on the delivery sides are
respectively able to be manufactured as radially symmetrical
deep drawn components. However it is readily possible to
manufacture the parts 1 and 4 as a single-piece deep drawn
component, which is then cut apart at the end surface 6 in
order to constitute a liquid outlet port. The second housing
part which is thus formed, namely the pllmp housing 4 part on
the delivery side, is then mounted at a distance from the
housing part 1 on the intake side and the two parts are joined
together by a separately produced spiral chamher 7. By means
of peripherally extending weldments 8 and 9 tlle two parts are
then joined to each other. Thus it is possible for the inlet
opening 10 into the spiral chamber 7 to he produced in an
extremely simple way by suitable positioning of the parts in
2 ~ r~
relation to each other.
As shown in figures 4 through 9 described below, it
is possible for the inlet opening 10 into the spiral chamber 7
to also consist of a plurality of inlet openings 10, which are
spaced out around the periphery and between which there are
ribs functioning to connect the structure together.
The embodiment of the invention illustrated in
figure 2 is different to that shown in figure 1 since in this
case the spiral chamber 7 is arranged between t~lo pump housing
parts 1 and 4 and is connected with the same.
Figure 3 is a view corresponding to a section taken
on the line III-III of figure 1. The spiral chanrher 7, whose
cross section varies along the periphery, is in the
illustrated working embodimemt manufactured by forming a
strip-like part with an increasing U-like cross section~ at
whose ends 11 and 12 two cups are formed which constitute the
delivery connection. The same are welded together along the
joint 14. The spiral chamher 7 formed in this manner may be
arranged on the outer circumferential surface of the intake
and/or delivery pump housing parts 1 and 4 and secured in
place by a conventional method. It is possihle to provide
connection flanges 15, see figure 1, in an extremely simple
way on the delivery connection 13, whose cross section widens
in the form of a diffusor.
Figure 4 illustrates a developed view of the part of
the inlet openiny 10 in the spiral chamber 7, which is
arranged between the intake and delivery pump housing parts 1
and 4. The latter are connected together by a plurality of
ribs 16~ which are spaced apart and span the intake opening
10. They are in the illustrated working embodiment welded to
2~ 3
the housing parts but any other suitable type of connection
would also be possible.
Figure 5 shows an embodiment of the invention in the
case of which the intake and delivery housing halves 1 and 4
are components of a single housing. The passage openings 10
for the pumped fluid coming from the impeller have in this
case been produced by stamping out rectangular pieces of the
material such openings being distributed over the periphery
and being spaced from each other. Between the openings 10 the
ribs 16 function to stiffen the housing.
A different form of stamped openings lO is shown in
figure 6. The opening 10 has a configuration like a letter U
so that adjacent to the ribs 16 there is a luy-like element 17
left in place.
As shown in figure 7 it is possihle for the lugs 17
to be bent upwards so that a fluid flowing from the impeller
will move through the passage openings l() with full guidance
control.
A further possible configuration is illustrated in
figure 8. Tlle stamped out holes for the passage opening lO in
this case have a configuration like a letter H. Therefore two
lugs 17 and 18 are produced which may be bent inwards and
outwards in order to in this manner to achieve fuller guiddnce
and a design like a yuide wheel.
A -~laim~--
1. A spir~-l hou~ing for a cert-t-~i~uyJl pump of ahe~
- metal construction consistin~-e~ ri~-~h~*~ Hh~ s-
arrarl(3ed downstrea~-f-rom an impeller and is in the form of~
