Note: Descriptions are shown in the official language in which they were submitted.
CA 02744917 2011-05-27
SHIP PROPULSION SYSTEM HAVING A PUMP JET
Description
The present invention relates to a ship propulsion system having a pump jet
according to
EP 0 612 657.
Such ship propulsion systems are known from practice, and they contain a pump
jet as
main and/or auxiliary drive. The energy supply occurs, for example, on one
hand, via a gear
system, with, as desired, a diesel, electric or hydraulic motor connected
before it, or directly via
an impeller shaft by means of a motor arranged outside of the drive. The
electric motors being
used are conventional electric motors.
Although such ship propulsion systems are extremely advantageous
constructions, the
present invention has and achieves the goal of a further improvement,
particularly with regard to
simplifying the construction, efficiency of the drive, and broadening of the
range of possible
applications.
For this purpose, the invention creates a ship propulsion system with a pump
jet, which
contains a pump housing and a drive motor, where a rotor of an impeller of the
pump jet contains
a rotational axis which is not aligned with a control axis of the pump jet.
This design can advantageously be further developed so that the rotational
axis of the
rotor is offset with respect to the control axis of the pump jet, where,
furthermore, it is preferred
for the rotational axis of the rotor and the control axis of the pump jet to
be parallel.
Alternatively or additionally, it is possible to provide advantageously that
the rotational axis of
the rotor and the control axis of the pump jet are mutually inclined, where,
furthermore, the
rotational axis of the rotor and the control axis of the pump jet intersect
particularly at one point.
Moreover, it is possible to provide advantageously that the drive motor is an
electric
motor which is set on the pump housing or integrated partially therein.
This design can advantageously be developed further in that the electric motor
is an
asynchronous motor, synchronous motor or permanent magnet motor, and/or in
that between the
electric motor and parts that transfer force to the impeller, such as teeth,
roller bearings and/or
shafts are provided.
An additional preferred embodiment is one in which the drive motor is a magnet
motor
integrated in the pump housing.
Alternatively, the invention creates a ship propulsion system with a pump jet,
which
contains a pump housing and a drive motor, where the drive motor is a high-
temperature
superconducting motor integrated in the pump housing.
It is preferred for the pump jet to be controllable all around.
Moreover, it is advantageous to provide that the magnet motor or high-
temperature
superconducting motor contains a rotor which is a component of an impeller of
the pump jet.
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An additional preferred embodiment consists in that the magnet motor or high-
temperature superconducting motor contains a stator which is a component of a
diffuser inner
ring of the pump jet.
Another preferred embodiment consists in that the conveyance medium is also
used
particularly by itself as lubricant and/or coolant.
An additional preferred embodiment consists in that the drive of the pump jet
is free of
force transferring parts, such as teeth, roller bearings and/or shafts.
According to an additional preferred embodiment, deflection devices are
provided which
are arranged and/or designed in the inner space of the diffuser housing.
The deflection devices are preferably arranged and/or designed so that they
eliminate
turbulence from a water flow in the inner space of the diffuser housing and/or
direct the water
flow in such a way that water exits through a nozzle of the pump jet as much
as possible without
internal turbulence or in such a way that through individual nozzles a desired
quantity of water
exits per unit of time, particularly the same amount of water per unit of time
and/or to the extent
possible without internal turbulence, to achieve an optimal thrust effect of
the pump jet. In
addition or alternatively, it is preferred for the deflection devices to
contain at least one shaping
of the inner space of the diffuser housing. An additional preferred design in
this connection
consists in that the deflection devices contain an area with constant cross-
sectional profile of the
inner space of the diffuser housing, and/or in that the deflection devices
contain an area with
reduced cross-sectional profile of the inner space of the diffuser housing,
and/or in that the
deflection devices contain an area with enlarged cross-sectional profile of
the inner space of the
diffuser housing. Furthermore, the deflection devices can alternatively or
additionally contain at
least one guide vane in the inner space of the diffuser.
Additional preferred and/or advantageous embodiments of the invention result
from the
claims and their combinations, as well as from all the available application
documents.
The invention is explained below using embodiment examples and in reference to
the
drawing, only as an example, where, in the drawing
Figure 1 shows, in a schematic cross-sectional view, a first embodiment of a
ship
propulsion system with a pump jet,
Figure 2 shows a schematic perspective view of the ship propulsion system with
a pump
jet of the first embodiment example,
Figure 3 shows a schematic view of the ship propulsion system with a pump jet
of the
first embodiment example from below, that is, in the case of a pump jet
attached to the hull of a
ship, in the viewing direction towards the hull,
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Figure 4 shows a schematic view of the ship propulsion system with a pump jet
of the
first embodiment example from the inside towards the outside, that is, in the
case of a pump jet
attached to the hull of a ship, in the viewing direction away from the hull,
Figure 5 shows, in a schematic view, a second embodiment example of a ship
propulsion
system with a pump jet, and
Figure 6 shows, in a schematic view, a third embodiment example of a ship
propulsion
system with a pump jet.
With the aid of the embodiment and application examples described below and
represented in the drawing, the invention is explained in further detail only
as an example, that
is, it is not limited to these embodiment and application examples or to the
combination of
characteristics within these embodiment and application examples. Method and
device
characteristics result in each case also analogously from the device and
method descriptions.
Individual characteristics which are indicated and/or represented in
connection with a
concrete embodiment example are not limited to this embodiment example or the
combination
with the other characteristics of this embodiment example; rather, they can be
combined, within
the scope of technical feasibility, with any other variants, even if they are
not discussed
separately in the available documents.
Identical reference numerals in the individual figures and depictions of the
drawing
denote identical or similar, or identically or similarly acting components.
With the help of the
depictions in the drawing, those characteristics are also to be illustrated
which are not provided
with reference numerals, regardless of whether or not such characteristics are
described below.
On the other hand, characteristics that are contained in the present
description, but not visible or
depicted in the drawing, are also easily understandable to a person skilled in
the art.
Figure 1 is a schematic view of a ship propulsion system S with a pump jet P
in a
longitudinal cross section. The pump jet P contains a magnet motor M which is
integrated in the
flow housing or pump housing G, as drive motor with a stator 1 and a rotor 2.
The rotor 2 is
developed as an impeller outer ring I, and the stator 1 is integrated in a
diffuser inner ring D of
the pump housing G, which contains a diffuser housing 3 or is designed overall
as such. The
pump jet P also comprises a control motor 4, a control drive 5, with, for
example, a spur wheel
R, as well as a receipt transmitter 6 and a well plate 7.
Figure 2 shows the ship propulsion system S with the pump jet P of the first
embodiment
examples in a schematic perspective view. Figure 3 shows the ship propulsion
drive S with a
pump jet P of the first embodiment example in a schematic view from below,
that is, in the case
of a pump jet attached to the hull of a ship, in the viewing direction towards
the hull. Figure 4
shows the ship propulsion system S with the pump jet P of the first embodiment
example in a
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schematic view from the inside towards the outside, that is, in the case of a
pump jet attached to
the hull of a ship, in the viewing direction away from the hull.
In particular, the ship propulsion system S is one that can be controlled all
around, and
whose pump jet P is mounted so it can be rotated by 360 . Besides the fact
that the drive of the
pump jet P occurs via a magnet motor M integrated in the pump housing G, it is
also possible to
provide, for the drive, a high-temperature superconducting or HTSC motor (not
shown
separately), where, in each case, the rotor 2 is more or less a component of
the impeller I, and the
stator 1 is an integrated component of the diffuser inner ring D. The
consequence is that it is not
necessary to use the conventional type of force transfer by means of drive
motor, gear system
and articulated shaft. As a result, a very compact drive unit is produced,
which can be built into
nearly any floating apparatus.
Due to the drive of the pump jet P with a magnet motor M or HTSC motor, no
drive gear
system parts, such as teeth, shafts, roller bearings are necessary. This has
the consequence that
the pump jet P can be classified as very low noise and low vibration, as well
as presenting a high
degree of efficiency. Furthermore, no oil filling for lubrication and cooling
of rotating parts is
necessary, which characterizes the pump jet P as oil free and low maintenance.
The particular resulting advantages are:
- compact design
- high degree of efficiency
- very low noise
- low vibration
- oil free
- low maintenance
By means of the control motor 4, the pump housing G, which contains the
diffuser
housing 3 or is designed overall as such, can be rotated in bearings 8 with
respect to the well
plate 7 about a control axis A precisely preferably by 360 , so that the
nozzles 9 can be
controlled in a desired direction, of which, in the cross-sectional view in
Figure 1, only one
middle nozzle 9b of three nozzles 9a, 9b and 9c (see Figures 2, 3 and 4) can
be seen.
Through a suction opening 10, water is drawn in by means of the rotor 2 into
an inner
space 11 of the diffuser housing 3. The water jet which thus flows into the
inner space 11 of the
diffuser housing 3 is deflected by the shaping of the inner space 11 of the
diffuser housing 3, so
that it exits through the nozzles 9 out of the pump housing G, precisely in
accordance with the
rotational position of the latter set by means of the control motor 4, in a
desired direction.
Because, as a result of the shaping of the inner space 11 of the diffuser
housing 3, a deflection of
the water flow, which enters through the suction opening 10 into the inner
space 11 of the
diffuser housing 3, is achieved, the diffuser housing 3 or the pump housing G
is thus
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simultaneously also a deflection housing. The shaping, in the first embodiment
example shown
in Figure 1, is bead like around the drive motor with the stator 1 in the
diffuser inner ring D of
the pump housing G, and the runner or rotor 2 as impeller outer ring I. The
inner space 11 of the
diffuser or deflection housing 3 with the specific shaping thus represents
deflection devices 12.
To further influence the flow of the water drawn in through the suction
opening 10 by
way of the nozzles 9, as seen in the depiction of Figure 4, a guide vane 13 is
provided as a
component of the deflection devices 12. Depending on the rest of the design of
the deflection
devices 12, several and/or differently positioned and designed guide vanes can
be provided. The
guide vanes, like the guide vane 13, serve the function of applying
"turbulence removal" to and
orienting the water flow with the deflection devices 12, water which enters or
is drawn in
through the inner space 11 of the diffuser or deflection housing 3, and which
is made turbulent
by the rapidly turning rotor 2, in such a way that, through the individual
nozzles 9a, 9b and 9c, in
each case, for example, the same quantity or in general a desired quantity of
water per unit of
time exits to the extent possible without internal turbulence, to achieve an
optimal thrust effect of
the pump jet P.
According to the present invention, although this is not visible in the
representation
chosen for Figure 1, the rotor 2 is provided with a rotational axis B which is
offset with respect
to the control axis A of the pump jet P; specifically, the rotational axis B
is offset towards the
rear, in reference to the drawing plane in which the control axis A is
located; that is, farther away
from the viewer. Such a type of offset is, however, clearly visible and
understandable when
looking at the second embodiment example according to Figure 5.
Figure 5 shows a schematic cross-sectional view, analogous to the
representation of
Figure 1, of a second embodiment of a ship propulsion system S with a pump jet
P. To prevent
repetitions, with regard to all the components, their arrangement and effect,
reference is made to
the description of the first embodiment example according to Figures 1-4.
In contrast to the first embodiment example, in the second embodiment example,
the
rotor 2 is provided with a rotational axis B that is offset with respect to
the control axis A of the
pump jet P. The control axis A of the pump jet P, and the rotational axis b
[sic] of the impeller or
rotor 2 are, however, oriented mutually parallel.
Moreover, the deflection devices 12, to the extent that they are formed by the
shaping of
the inner space 11 of the diffuser or deflection housing 3 or of the pump
housing G, in the
present second embodiment example according to Figure 5, are no longer of
identical shape
around the rotor 2, in comparison to the embodiment of the first embodiment
example according
to Figure 1. The deflection devices 12 have an area 12a with smaller cross-
sectional profile and
an area 12b with larger cross-sectional profile; on the other hand, the cross-
sectional profile in
the entire area 12c in the first embodiment example according to Figure 1 is
constant. A cross
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section which becomes larger towards the nozzles 9, in accordance with the
area 12b - with
reference to the cross section in the area 12a - of the second embodiment
example according to
Figure 5 has, for example, a diffusion or diffuser effect.
It is precisely the offset arrangement of control axis A of the pump jet P and
rotational
axis B of the impeller I or rotor 2 that favors the design of the deflection
devices 12 with the area
12a having a smaller cross-sectional profile and with the area 12b having a
larger cross-sectional
profile. However, the two aspects, on one hand, the offset of the axes, and,
on the other hand, the
irregular design of the deflection devices 12 in the inner space 11 of the
diffuser or deflection
housing 3 or of the pump housing G do not necessarily have to be combined.
In Figure 6, in a schematic cross-sectional representation analogous to the
representation of Figures 1 and 5 - a third embodiment example of a ship
propulsion system S
with a pump jet P is shown. To prevent repetition, with regard to all the
components, their
arrangement and effect, reference is made to the description of the first
embodiment example
according to Figures 1-4.
In contrast to the first embodiment example, in the third embodiment example,
the rotor 2
presents a rotational axis B which is inclined with respect to the control A
of the pump jet P. The
control axis A of the pump jet P and the rotational axis B of rotor 2
intersect, however, at a point
Z.
Moreover, in the third embodiment example according to Figure 6 as well, as in
the
second embodiment example according to Figure 5, the deflection devices 12, to
the extent that
they are formed by the shaping of the inner space 11 of the diffuser or
deflection housing 3 or of
the pump housing G, in comparison to the design in the first embodiment
example according to
Figure 1, no longer present the same shape around the rotor 2, due to its
inclined position. The
deflection devices 12 again, as in the second example according to Figure 5,
have an area 12a
with smaller cross-sectional profile and an area 12b with a larger cross-
sectional profile; in
contrast, as already explained above, the cross-sectional profile is constant
in the entire area 12c
in the first embodiment example according to Figure 1. A cross section which
becomes larger
towards the nozzles 9, in accordance with the area 12b - with reference to the
cross section in
the area 12a - of the second embodiment example according to Figure 6 has, for
example, a
diffusion or diffuser effect.
It is precisely the inclined arrangement of rotational axis B of the impeller
I or rotor 2
with respect to the control axis A of the pump jet P which favors the design
of the deflection
devices 12 with the area 12a having a smaller cross-sectional profile and the
area 12b having a
larger cross-sectional profile. In the design according to the third
embodiment example, which is
illustrated in Figure 6, the areas 12a and 12b are, however, in terms of cross
section not constant
even in a peripheral section of the bead or ring shaped inner space 11 of the
diffuser or deflection
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housing 3 or of the pump housing G, as is the case in the second embodiment
example according
to Figure 5.
Moreover, in the third embodiment example as well, which is illustrated in
Figure 6, it is
not necessary to combine, on the one hand, the inclination of the axis towards
each other, and, on
the other hand, an irregular design of the deflection devices 12 in the inner
space 11 of the
diffuser or deflection housing 3 or of the pump housing P.
The aspect that the rotational axis B of the impeller I or of the rotor 2, and
the control
axis A of the pump jet P are not in alignment, or in other words are not
superposed or
overlapping, can also be considered to be an independent invention, which is
thus in itself
worthy of invention protection, independently of the design of the ship
propulsion system S with
a pump jet P, which contains a pump housing G and a drive motor, where the
drive motor is a
magnet motor M or high-temperature superconducting motor integrated in the
pump housing G.
The nonaligned arrangement of the rotational axis B of the impeller I or rotor
2, and of the
control axis A of the pump jet P is here the generally valid formulation,
which covers the
embodiment examples according to Figures 5 and 6, in which, in the second
embodiment
example, the rotor 2 is provided with a rotational axis B which is offset with
respect to the
control axis A of the pump jet P, or, in the third embodiment example, the
rotor 2 presents a
rotational axis B, which is inclined with respect to the control axis A of the
pump jet P, where
the control axis A of the pump jet P and the rotational axis B of the rotor 2
intersect particularly,
but not necessarily, at a point Z.
In contrast to the described embodiments, one can use, as drive motor, instead
of the
magnet motor M or HTSC motor, alternatively also an electric motor E, such as,
for example,
particularly an asynchronous motor, synchronous motor or permanent magnet
motor, which is
placed on the pump housing G or partially integrated therein. Such an electric
motor E is
indicated only with broken lines in Figures 5 and 6 in connection with the
second and third
embodiment examples for clarification. If such an electric motor E is
provided, it replaces the
magnet motor M or the HTSC motor, which, in the first embodiment example
according to
Figure 1, is provided as the only variant for the drive motor, and which,
precisely in the second
and third embodiment examples, can be provided in each case as the only drive
motor. As
indicated, the variants of a drive motor in the form of a magnet motor M or
HTSC motor
integrated in the pump housing G, on the one hand, and of an electric motor E
placed on the
pump housing G or partially integrated therein are alternatives, if the
inventive aspect of the
nonaligned axes, namely the rotational axis B of the impeller or rotor 2 and
the control axis A of
the pump jet P, is considered separately. When using an electric motor E as a
drive motor placed
on the pump housing G or integrated therein, force transferring parts, such as
teeth, roller
bearings and/or shafts are of course necessary, to ensure the rotatory
connection between such a
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drive motor and the impeller of the pump jet P; however, this is part of the
standard knowledge
of a person skilled in the art, and to that extent not a component of the
present invention, and
also not part of the inventive aspect that the rotational axis b of the
impeller or rotor 2 and the
control axis A of the pump jet P are not in alignment.
The invention is illustrated merely as an example using the embodiment
examples in the
description and in the drawing, and it is not limited to those examples,
rather it comprises all the
variants, modifications, substitutions and combinations that the person
skilled in the art can
obtain from the available documents, particularly in the context of the claim
and the general
presentations in the introduction of this description as well as the
description of the embodiment
examples, and combine with his/her specialized knowledge as well as the prior
art. In particular,
all the characteristics and design possibilities of the invention and their
embodiment examples
can be combined.
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