EP1545970B1 - Water jet drive for marine vehicles - Google Patents

Abstract

A compact operational retro-fit drive plant, for installation in the base of the bow or stern of various types of marine vehicle, in particular of displacement types, which serves for maneuvering and traveling at cruising speed on normal and particularly flat stretches of water. The drive plant includes a simple and economically produced water jet drive ( 1 ), having a propeller pump ( 8 ), for various types of engine and installations, which generates an efficient and completely controllable propeller thrust with optimized propeller approach flow and flat water capability. The propeller shaft ( 11 ) of the water jet drive ( 1 ) is arranged on the pressure side of the propeller pump ( 8 ) in a conventional 90 DEG elbow tube ( 6 ), the rotational axis ( 9 ) of the propeller is neither vertical nor horizontal, but has an inclination angle alpha of 20 DEG to 50 DEG, preferably between 25 DEG and 40 DEG relative to the baseplate ( 20 ) as a horizontal base. At the other end ( 14 ) of the elbow tube ( 6 ), which points downwards at an angle, an outlet housing section ( 7 ) is connected thereto and provided with a rotating base deflector array ( 16 ), in order to have control in all directions over the exit jet and thus the propeller thrust under the base of the water jet drive ( 1 ).

Description

The invention relates to a water jet drive for watercraft.

In particular in the case of vessels which are also used in shallow waters (for example on inland waters with varying water levels), waterjet propulsion systems which are preferably arranged on the bow side in the ground area have proved to be suitable for improving the maneuverability. Such water jet drives, also referred to as bow jet systems, comprise a housing which can be installed in the respective vehicle floor and contains at least one propeller (or a pump impeller) which supplies energy to the water supplied via a bottom housing inlet and, for example, via a manifold and channels in the latter Direction radiates, or by at least one floor level and usually 360 ° swiveling outlet under the ship's bottom controls all around.

In known water jet drives, the axis of rotation of the propeller or the pump impeller extends either in the horizontal or vertical direction.

In a vertical propeller arrangement, that is to say when rotating about a horizontal transverse axis in a transverse jet tunnel, it should be noted that the waterline should be about half the diameter of the propeller above the tunnel vertex in order to avoid air drops and the resulting thrust drop. This has the disadvantage that the vessel in question has a relatively large draft and requires a corresponding fairway depth in order to maneuver it risk-free and efficient.

In addition to these water jet drives with vertical propeller arrangement are known, which have a bottom inlet to reduce the draft according to the principle of conventional axial jets. Because the intake behavior of axial propeller pumps only allows a limited divergence of the propeller blades, a function-related draft ratio must be ensured.

EP 0 024 443 A discloses a water jet drive for the bow control of a watercraft with a horizontally oriented propeller rotation axis. In this known water jet drive, the outlet opening for the water jet is in the direction of travel in front of the inlet opening, so that only a brake shoe and to support the rear-end rudder a maneuvering thrust can be generated. On the other hand, can be produced with such a constructed and arranged in the ship's bow water jet propulsion no economic driving thrust, because a propulsion generating and thus relatively flat inclined thrust jet in the straight ahead crossing the there steeply upward intake flow bsw. strongly swirled. The resulting turbulence and suction effects greatly increase the inlet losses and thus drastically reduce the thrust development in this control zone. The propeller water, which has also been sucked in at the same time, also contributes to the reduction in thrust, because it is less accelerated at higher entry speeds and thus produces less thrust.

Water jet drives with vertically oriented axis of rotation need for the over a bottom inlet horizontally arranged propeller (or pump impeller) Although a relatively small draft for air-free work, but have the disadvantage, inter alia, that such drives at low water depth (ie at less than, for example, about 50 cm Water under the keel) by their suction directed directly to the bottom create a strong suction, which increases the ship's resistance and affects the thrust development or completely collapse, when increasingly sucked foreign bodies enforce the usually existing protective grid.

Furthermore, the risk of damage increases because small foreign bodies pass through the protective grid like a sieve and can increasingly get into or between the blading.

In addition, it has been found that in waterjet drives with vertically oriented propeller axis with increasing travel, the flow to be deflected into the vertical intake begins to break off at a certain speed, which then results in a drastic drop in propulsion.

For propulsion via a horizontally arranged engine, water jet drives with a vertical propeller rotation axis require their own angular gear. And for propulsion via internal combustion engines for coupling and switching the direction of rotation (for example, to rinse the protective grid) nor a ship's turn gear required, which increases the mechanical losses and the cost of the system as a second transmission.

From CH 551 311 A a water jet drive for bow control for ships is known, in which a propeller is provided, whose axis relative to a horizontal base has an inclination angle ≤ 45 °. As in the case of the above-mentioned EP 0 024 443 A, the outlet opening for the water jet is in the direction of travel in front of the inlet opening. The self-closing louvers arranged behind the propeller and the rudder effect, which is efficient only in one beam direction, preclude the use of this drive for the generation of driving slip.

Finally, from US 3,263,643 a hovercraft is known, which has both stern and bow-side jet engines. In both drives, the respective propeller shaft is located on the suction side of the corresponding propeller, so that it comes to the operation of these drives to strong eddies of the respective water flow, which the cavitation-sensitive propeller suction side is supplied. As a result, not only the risk of damage to the propeller is increased by cavitation, but also the efficiency of such drives is not optimal. In addition, relatively high vibrations are associated with the operation of such drives.

The invention is based on the object, as simple and inexpensive to produce water jet propulsion with a propeller pump for watercraft, especially for positive displacement vehicles indicate that generates an optimized thrust with optimized flow during maneuvering and increasing speed and better shallow water properties on-through the propeller, which is inclined towards the primary direction of flow, and the conical pump inlet nozzle, which avoids harmful accumulations of air in the upper intake area (in contrast to round intake nozzles), the intake behavior is partially influenced by partially dipping propeller blades. Compared with water jet drives with horizontal propeller axis of the required draft is well below.

By not directing the suction action of the relatively flat inclined propeller to the bottom and increasing the inlet opening (in relation to the propeller diameter of other waterjet drives), the shallow-water properties with regard to thrust development, suction effect and resistance are improved.

In order to achieve a particularly compact design of the water jet drive according to the invention, it has proven to be advantageous if the water jet drive consists of an insertable into the ship's bottom housing unit, which is formed from at least four interconnected housing sections: a preferably designed for displacement vehicles flush floor inlet - housing section, concentrically connected to a tubular pump housing section with an axis inclined to the horizontal. At the other end of this pump housing section an arcuate housing section is attached at the same inclination, which serves as a housing base with an integrated propeller shaft bearing and which is preferably formed by a commercially available 90 ° round arch, but can also be designed in any other way. At the other obliquely downward-pointing end of the arc a floor-mounted outlet housing section is added, in which there is a storage of a controllable Bodenumlenkgitters.

For optimal flow of the propeller as a prerequisite for efficient thrust development for maneuvering while standing or at low travel speed, but also for driving up to marching speed, the inlet housing section is designed according to special shape and cross-sectional features, the different flow conditions (as in the suction - and supply operation in stationary pumps in a similar manner) best meet.

Starting flat, the inlet - housing contour above the inlet opening assumes a trapezoidal cross-section with rounded corners until the corner radii form a curved cross-section with a circular radius, to which a conical pump inlet nozzle attaches.

By aligning the contours of this inlet - housing section in the main direction of travel (ie straight ahead) and at the same time also lateral or oblique inflows be detected funnel-like, the water is optimally supplied to the propeller inclined to the flow.

The tubular pump housing section, which is arranged between the inlet housing section and the pipe bend and which consists of a particularly corrosion - resistant. wear-resistant material is provided forms a centric pump housing with at least one propeller and behind fixed stator blades, which convert the spin energy into flow energy and at the same time serve as webs to support the central bearing hub, a propeller pump. An alternative support of the bearing hub e.g. with spokes of round cross section, etc. is also conceivable and included.

Depending on the conditions of the vessels and the required drive power are mainly electric u. Combustion engines but also hydraulic motors used to drive. When using electric motors, different drive speeds are specified depending on the on-board frequency (for example 50 or 60 Hz) and motor design (pole pair number). Therefore, it has proved to be advantageous if the electric motor can be attached either directly by means of a coaxial bell housing or parallel to the axis and by means of high-performance belt drive and selectable reduction gear on the water jet drive or on the right or left side of the housing unit.

If the waterjet propulsion system is to be driven by an internal combustion engine, it has proved particularly expedient to connect the internal combustion engine to the propeller shaft via a marine gearbox in a so-called V version with a standard axle inclination angle of, for example, 10 °. As a result, a particularly compact installation of the internal combustion engine on the water jet drive is possible. Preferably, the engine and transmission can be aligned with each other on a common base frame and fixed, which in turn is then based as an elastically mounted unit mounted on the water jet propulsion consoles. In addition to the standard reduction options for speed adaptation, the turning stage of this marine gearbox can be used for flushing the inlet protection grille.

In order to achieve efficient thrust in predominantly shallow water use, the inlet housing section can be designed in special installation-specific variants. For example, by making the entry level of the leading or a lateral leading edge a little higher u./od. By varying the inclination of the front or side casing surface, flat open areas can be created in the bow area or on the side of a watercraft so that additional (air-free) water can flow directly to the propeller from the front or from the side. (For example, in pontoon or double end ferries with lateral or diagonal jet installation.)

Moreover, the waterjet propulsion system according to the invention can be used for different types of vessels and for different purposes, e.g. as a maneuvering u. Auxiliary system and / or used as a main propulsion system at various positions in the vehicle floor. As vehicle types are mainly inland vessels, such as cargo, passenger and work ships and ferries, landing craft, government vehicles and those with increased requirements for holding positions such. Fire-fighting boats, diver ships, measuring u. Laboratory vessels etc. into consideration. However, the water jet drive according to the invention can also with appropriate design as a maneuvering in coastal u. Oceangoing ships are used.

• Fig.1 den Längsschnitt eines erfindungsgemäßen Wasserstrahlantriebes mit einem Elektromotor als koaxialer Direktantrieb oder in achsparalleler Anordnung mit einem Riementrieb;
• Fig.2 eine Bodenansicht des in Fig. 1 dargestellten Wasserstrahlantriebes aus der in Fig. 1 mit II bezeichneten Richtung;
• Fig. 3 und 4 zwei Schnitte entlang der in Fig.2 mit III - III und IV - IV bezeichneten Schnittlinien;
• Fig.5 den Längsschnitt des in Fig.1 dargestellten Wasserstrahlantriebs mit einem Verbrennungsmotor als Antrieb.

Further details and advantages of the invention will become apparent from the following with reference to figures explained embodiments. Show it:

• 1 shows the longitudinal section of a water jet drive according to the invention with an electric motor as a coaxial direct drive or in an axially parallel arrangement with a belt drive;
• FIG. 2 shows a bottom view of the water jet drive shown in FIG. 1 from the direction indicated by II in FIG. 1;
• FIGS. 3 and 4 show two sections along the section lines labeled III-III and IV-IV in FIG.
• 5 shows the longitudinal section of the water jet drive shown in Figure 1 with an internal combustion engine as a drive.

In Fig.1 with 1 an inventive water jet drive is referred to, driven either via a coaxially mounted electric motor 2 (in flange) or an axially parallel mounted electric motor 2 '(foot version) by means of belt drive 38 and corresponding reduction with the desired propeller speed or peripheral speed can be.

The water jet propulsion system 1 consists of a housing unit 3 which can be inserted into the ship bottom (not shown) and consists of four housing sections 4 - 7 connected to one another: a floor - mounted inlet housing section 4 preferably designed for positive displacement vehicles, to which a tubular pump housing section 5 concentrically surrounds Recording a propeller 10 connects. According to the invention, the propeller rotation axis 9 and thus also the propeller shaft 11 are arranged at an angle of inclination α of preferably 28 ° with respect to a horizontal base formed by the base plate 20 of the housing unit 3.

In the direction of the inclined propeller axis of rotation 9, a pipe bend 6 is added to the pump - housing section 5, which serves to support the propeller shaft 11 as a housing base and which may be a commercially available 90 ° - round arch. At the other obliquely downward-pointing arc end 14 of the pipe bend 6 is a floor-mounted outlet housing section 7 with an outlet opening 15 is added, in which a pivotable Bodenumlenkgitter 16 is arranged to control the water jet.

For the implementation, storage and sealing of the control shaft 17 and the propeller shaft 11 concentric bearing stub 18, 19 are arranged on the round arch 6 to the respective shaft axes.

The water-conducting housing sections 4 - 7 and a bottom plate 20 connecting the inlet and outlet openings 13 and 15 are interconnected to form a pre-producible housing unit 3, which is provided with corresponding motor consoles 37 or foundation brackets 45, 46 for installation of the desired drive motor 2, 2 'and 40 can be completed.

Further, the housing unit 3 with an inspection cover on the idle water line (not shown) executable that allows inspection from the engine room and cleaning the inlet area.

By orienting the contours of the inlet housing section 4 in the main direction of travel (i.e., in straight ahead travel), the water is optimally supplied to the propeller 10, which is inclined towards the flow. About the FIG. 3 u. 4 obliquely outwardly issued side surfaces of the inlet housing section 4 are also detected with funnel-like effect oblique or lateral flows.

The contours of the inlet housing section 4 are selected such that the profiles of the tunnel cross sections 21, 22 in Fig. 3 u. 4 with respect to their height and their upper corner radii steadily increase until they form a tunnel with a circular curvature, to which a conical pump inlet nozzle 23 attaches. Below the propeller axis of rotation 9, the contour of the pump inlet nozzle 23 decreases until it merges into the bottom plate 20 downwards. Alternative versions are conceivable and included.

In the area of the inlet opening 13 of the inlet housing section 4 is a protective grid 24 against foreign bodies of detrimental size, which either fixed - or shaking evt. Foreign body - is pivotally mounted and disassembly easy accessibility of the inlet region and the propeller 10 for inspection , Maintenance and repair possible.

The tubular pump housing section 5 arranged between the inlet housing section 4 and the pipe bend 6 forms, with a narrow radial gap around at least one propeller 10, the pump housing and, together with the guide vanes 26 arranged behind it, which convert the swirl energy into flow energy and at the same time support the bearing hub 27 Serve, the propeller pump 8. Similarly, an alternative hub support, for example, with unprofiled spokes (instead of 26) conceivable and included. The propeller side Bearing hub 27 preferably includes a conventional water lubricated propeller shaft sleeve bearing 39.

The upper double-sealed propeller shaft bearing 28 is provided as a grease-lubricated roller bearing for receiving axial and radial loads and arranged in the attached to the pipe bend 6 bearing stub 19.

In the outlet housing section 7, a bearing hub 30 which is supported via webs 29 is likewise arranged for receiving and supporting the floor deflection grille, wherein at least two webs 29 are arranged above the front floor half in such a way that they favor the flow guidance on or through the floor deflection grille 16.

For all-round control of the Bodenumlenkgitters 16, the vertical control shaft 17 below preferably in a water-lubricated plain bearing 31 and above in a sealed on both sides and greased roller bearing 32, which can accommodate axial and radial loads stored in the bearing stub 18 of the housing unit 3. On the control shaft 17 is a drive hub 33 for the (not shown) control drive and a small output hub 34 for the (not shown) optical u. elec. Thrust direction indicator arranged.

The electric motor 2 (in flange design) is connected via an elastic shaft coupling 35 with the propeller shaft 11 and mounted via a coaxial bell housing 36 on the bearing neck 19 of the housing unit 3. The use of an electric motor 2 '(in Fußausführung) and a corresponding high-performance belt drive 38 for driving the propeller shaft 11 allow the adaptation of frequency-dependent engine speeds to a single propeller speed or to a certain peripheral speed. Depending on the given space conditions, the electric motors 2, 2 'can be installed either in front of the propeller shaft 11 or by means of an axially parallel motor bracket 37 above or laterally on the housing unit 3 of the water jet drive 1 ready for use drive unit.

In the embodiment of the invention shown in Fig. 5, an internal combustion engine 40 for driving the water jet drive 1 is provided. In order to achieve a compact and advantageous arrangement of the drive components, the internal combustion engine 40 with the torsionally flexible engine clutch 41 attached thereto is together with a commercial marine gearbox 42, preferably in a V version (ie, the horizontal drive and the inclined output axles form one "Lying V") mounted on a common base frame 43 and positioned so that the connecting propeller shaft 44 results in a W - arrangement with two equal diffraction angles in a permissible size.

The base frame 43 is aligned on foundation brackets 45, 46, which are arranged on the housing unit 3, at least four points via rubber - metal - damping elements 47 to the propeller shaft 11 and elastically mounted. Load-dependent displacements or deflections are compensated by the elastic shaft coupling 48 in double cardan design. In addition, the rubber-metal damping elements 47 and the two elastic elements of the coupling 48 simultaneously serve to effectively dampen the transmission of vibrations and structure-borne noise to the water-jet drive 1 and thus to the hull.

Of course, the invention is not limited to the embodiment described above. Thus, instead of the single-stage propeller pump 8 shown in FIGS. 1-5, the water-jet drive can in principle also be designed with a two-stage propeller pump (pump with a propeller shaft 11 and two propellers 10 with guide vanes 26 therebetween).

Moreover, instead of a fixed propeller pump, the water jet drive 1 can in principle also be realized with a variable pitch propeller pump, in which case the propeller shaft 11 is hollow drilled in order, for example, to guide an actuating rod or lines for adjusting the propeller blades (or the propeller pitch). In a drive by means of axially parallel installed electric motor, the device for pitch adjustment in front of the bearing neck 19 on the water jet drive 1 can be mounted. In the case of an internal combustion engine as a drive motor, for example, an extended actuating rod through the shaft coupling 48 and the hollow-drilled output shaft of the marine gear 42 can be passed, so that the adjustment - as usual - outside the marine gearbox 42 is attachable.

LIST OF REFERENCE NUMBERS

1

Water jet propulsion

2, 2 '

Electric motor, drive

3

housing unit

4

Inlet housing section, housing section

5

Pump housing section, housing section

6

Pipe bend, curved housing section

7

Outlet housing section, housing section

8th

Propeller pump, pump

9

Propeller rotation axis

10

propeller

11

propeller shaft

12

Base

13

inlet opening

14

arch end

15

outlet opening

16

Bodenumlenkgitter

17

control shaft

18

Bearing neck (control shaft)

19

Bearing neck (propeller shaft)

20

baseplate

21

Tunnel cross section

22

arched tunnel cross-section

23

pump intake

24

guard

25

stator

26

vane

27

bearing hub

28

sealed rolling bearing (propeller shaft)

29

web

30

bearing hub

31

bearings

32

sealed rolling bearing (control shaft)

33

drive hub

34

output hub

35

elastic shaft coupling

36

housing bell

37

Motorkonsole

38

belt drive

39

Propeller Shafts - plain bearings

40

Internal combustion engine, engine, drive

41

torsionally elastic engine clutch

42

Marine gearbox, gearbox

43

base frame

44

propeller shaft

45

Base console

46

Base console

47

Rubber - metal - damping element

48

elastic double cardan - shaft coupling, coupling

49

gear console

Claims (10)

1. A hydrojet for watercraft with the features:

   a) the hydrojet (1) comprises a housing unit (3), which can be installed in the bottom of the respective watercraft and contains at least one said propeller (10) that can be rotated about a propeller axis (9) and delivers the water entering through a bottom - side intake opening (13) and through an intake housing section (4) of the housing unit (3) through a bend (6) and through a bottom deflecting grid (16) arranged rotatably by a steering shaft (17) in a discharge opening (15) of the housing unit (3), in which the discharge opening is flush with the bottom, and thus releases it under the housing unit (3);

   b) the hydrojet (1) being designed such that the intake housing section (4) is aligned with the main direction of travel in case of the normal use of the hydrojet (1) and the bottom-side intake opening (13) of the housing unit (3) is arranged in front of the discharge opening (15);
   characterized in that:

   c) the propeller (10) forms an axial-flow pump (8), which is in functional connection with a drive (2, 2', 40), at least with a propeller shaft (11), arranged at the pressure area in the bend (6) and with a pump housing section (5) of the housing unit (3); and

   d) the axis of rotation (9) of the propeller (10) sloping towards the primary flow direction, which axis of rotation (9) extends at an angle down to the intake opening (13) of the housing unit (3), has a slope angle (α) between 20° and 50° in relation to the bottom plate (20) as a horizontal base.
2. A hydrojet in accordance with claim 1, characterized in that the axis of rotation (9) of the propeller has a slope angle (α) between 25° and 40° in relation to the bottom plate (20) as a horizontal base.
3. A hydrojet in accordance with claim 1 or 2, characterized in that the housing unit (3) of the hydrojet (1) comprises at least four housing sections (4-7) connected with one another: an intake housing section (4), through which the water enters the pump (8), a tubular pump housing section (5) comprising the propeller (10), a bent housing section (6) for deflecting the flow of water, and a discharge housing section (7) provided with a pivotable bottom deflecting grid (16).
4. A hydrojet in accordance with claim 3, characterized in that above the intake opening (13), the contour of the intake housing section (4) forms a trapezoidal tunnel cross section (21), which forms a, circularly arched tunnel cross section (22) in the course of the further rise and then passes over, via a conical pump intake nozzle (23), into a circular cross section, which opens concentrically into the pump housing section (5) of the housing unit (3).
5. A hydrojet in accordance with claim 3 or 4, characterized in that the bent housing section (6) is a 90° pipe bend.
6. A hydrojet in accordance with one of the claims 1 through 5, characterized in that the drive (2, 2') of the pump (8) is an electric motor, which is fastened to the housing unit (3) either on the front side or axially in parallel to the propeller shaft (11).
7. A hydrojet in accordance with one of the claims 1 through 5, characterized in that the drive (40) of the pump (8) is an internal combustion engine, which is fastened to the housing unit (3), wherein the drive (40) and the propeller shaft (11) are connected at least via a gear (42), which has ist power input and power output on the same side.
8. A hydrojet in accordance with one of the claims 1 through 7, characterized in that a protective grid (24) is arranged in the intake housing section (4) of the housing unit (3).
9. A hydrojet in accordance with one of the claims 1 through 8, characterized in that the pump (8) in the housing unit (3) is a two-stage axial-flow pump, which has two said propellers (10) on the propeller shaft (11) and at least one said guide vane (26) located in between to rectify the flow.
10. A hydrojet in accordance with one of the claims 1 through 8, characterized in that the propeller (10) of the pump (8) is a variable-pitch propeller.

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