EP1687201B1 - Jet propulsion engine - Google Patents

Abstract

The invention relates to a jet propulsion engine, especially for watercraft, comprising a rotor ( 1 ) on the inside of which blades ( 2 ) are disposed, and a housing ( 3 ) in which the rotor ( 1 ) is rotationally received. The bearing system between the rotor ( 1 ) and the housing ( 3 ) is produced from carbide that is resistant to sea-water. ( 57 ) Zusammenfassung: Die Erfindung betrifft einen Strahlantrieb insbesondere für Wasserfahrzeuge mit einem Rotor ( 1 ), an dessen Innenseite Schaufeln ( 2 ) angeordnet sind und einem Gehäuse ( 3 ), in dem der Rotor ( 1 ) drehbar gelagert ist, wobei die Lagerung zwischen Rotor ( 1 ) und Gehäuse ( 3 ) seewasserfestes Carbid aufweist.

Description

The invention relates to a jet propulsion, in particular for watercraft with a rotor, on the inside of which blades are arranged and a housing in which the rotor is rotatably mounted.

Such a jet propulsion system is known, for example, from US 2001/029133 which discloses all the features of the preamble of claim 1, and DE 39 12 910 C2, in which case the rotor is designed in the form of a tube with an internal screw.

The drive of the motor can be realized mechanically or in the form of an electric ring motor in which the rotor thus forms part of the electric motor.

With increasing diameter of the rotor increases the problem of storage between the rotor and housing.

Ball or roller bearings must be sealed in particular when using the jet propulsion for watercraft against ingress of water.

Extensive tests have shown that although a seal can be achieved with great effort, but the creep strength proved to be a very big problem, since with entering leak in the shortest possible time damage to the storage occurred.

The invention is therefore based on the object for the above-mentioned jet propulsion propose a storage that ensures a long service life.

In addition, the storage should also allow the realization of large rotor diameters for high performance jet engines.

This object is achieved in that the storage between rotor and housing seawater-proof carbide has.

By using seawater-solid carbide, the bearing no longer needs to be sealed, so that the bearing damage is cleared from the outset in the event of leakage.

Preferably, silicon carbide or aluminum carbide is used, since these two materials, in particular silicon carbide high resistance to salt water and on the other hand have the necessary strength.

Furthermore, it is advantageous to form the bearing between rotor and housing exclusively of carbide, as in addition to materials used for storage either non-corrosion resistant or have a lower seawater resistance and thus this would lead to premature wear of the storage.

Due to the good sliding properties of the carbide in conjunction with a water film storage is conveniently designed as a sliding bearing.

According to a preferred embodiment, the bearing in the rotor and / or the bearing in the housing is formed from a plurality of bearing segments.

For large bearing diameters, a one-piece production of the carbide bearing is almost impossible. About the production of storage over several bearing segments, however, can be realized almost unlimited large diameter.

In the formation of storage by a plurality of bearing segments, it is advantageous at least on the rotor, the bearing segments spaced form, so that by the centrifugal force Water between the bearing segments is pressed outwards and thereby results in a pumping action.

As a result of the pumping action, the bearing segments are thus inevitably lapped, which leads to improved heat dissipation.

In particular, in the training as Elektroringmotor the housing surrounds the rotor such that there is a cavity between the outside of the rotor and the inside of the housing.

In this embodiment, it is favorable on one side of the bearing bearing segments on the rotor and on the opposite side of the bearing segments on the housing to be spaced, so that the pumping action by the spaced bearing segments on the rotor, the water pressed into the cavity and back over the spaced bearing segments can be flushed on the housing to the outside.

However, it is also possible on both sides of the bearing segments on the rotor to space, so that on both sides of a pumping action in the direction of the cavity and the cavity towards the outside, for example, through a bore in the housing or more holes in the housing to open, so that the desired flow for cooling the bearings and the Elektroringmotors can arise.

The fixation of the bearing segments on the rotor or housing is conveniently carried out by positive engagement, for example by means of a trapezoidal geometry and possibly subsequent gluing.

Figur 1

zeigt eine Seitenansicht des erfindungsgemäßen Strahlantriebes,

Figur 2

im wesentlichen den Schnitt AA aus Figur 1, wobei Halterung und Schaufeln nicht dargestellt sind,

Figur 3

in vergrößerter Darstellung den unteren Teil aus Figur 2,

Figur 4

eine vergrößerte perspektivische Teilansicht der Lagerung im Gehäuse,

Figur 5a und 5b

Stirn und Seitenansicht eines Lagersegmentes für den Rotor und

Figur 6

einen Teilkreis der nebeneinander gereihten Lagersegmente am Rotor.

The invention will be explained in more detail with reference to an embodiment shown in the drawings.

FIG. 1

shows a side view of the jet drive according to the invention,

FIG. 2

essentially the section AA of Figure 1, wherein the holder and blades are not shown,

FIG. 3

in an enlarged view the lower part of Figure 2,

FIG. 4

an enlarged perspective partial view of the storage in the housing,

FIGS. 5a and 5b

Brow and side view of a bearing segment for the rotor and

FIG. 6

a circle of juxtaposed bearing segments on the rotor.

Figure 1 shows a side view of a jet propulsion for watercraft, which is based on the drive concept of a Elektroringmotors.

In section, part of a boat hull 19 is shown with an opening 20 through which the jet drive can be extended and retracted. In the hull 19 for this purpose, a shaft 21 is formed, in which the jet drive is received in the retracted state.

The jet drive has a rotor 1, on the inside of which inwardly directed blades 2 are arranged. The blades 2 are fixed by clamping on the rotor 1 and can each be replaced individually.

The rotor 1 is accommodated in a housing 3, which in turn is connected to a holder 4.

The holder 4 has a flange 5 towards the housing 3 and is connected via the flange 5 to the housing 3.

The holder 4 is designed as a hydraulic cylinder which is fixed at its upper end via a screw 6 to a cover 7 of the shaft 21.

The boat is an unillustrated generator or other power source, usually a diesel generator, which supplies the jet engine via a line 8 with the necessary power.

For retraction and extension and ur control of the jet propulsion of the hydraulic cylinder 4 is received in a sleeve 22 with groove 23 into which a pin 24 engages, which in turn is fixedly connected to the cover 7. The bolt 24 and the groove 23 form a slotted guide, so that extended in the straight part of the groove of the jet drive and is rotated in the helically extending part of the groove of the jet drive.

Retraction and extension and control can thus be done via the hydraulic cylinder 4. This has for this purpose only at the top of an inlet 25 and outlet 26.

At the bottom of the sleeve 22, a sealing plate 27 is arranged with sealing bead 28 to hold the water from the upper part of the shaft.

The opening 20 is closable via a Lammellenrolo 29, which via a drive 30, for. also in the form of a hydraulic or pneumatic cylinder can be closed.

In the extended state, the jet drive is shown in dashed lines.

Depending on the design of the jet propulsion system, this can be used as the main drive and also only as an additional maneuvering aid, since it can easily be swiveled through 360 ° and, due to its low weight, can easily be turned on and pulled out.

FIG. 2 essentially shows the section AA from FIG. 1, wherein only the inner life between the rotor 1 and the housing 3 is shown and a representation of the blades 2 has been dispensed with.

Figure 3 shows the lower part of Figure 2 in an enlarged view.

The rotor 1 consists essentially of the two rotor parts 1a and 1b, which are screwed together and clamped between them receive an electric motor rotor ring 9 on its outside centric.

The retaining flanges 10a and 10b for fixing the blade segments are respectively provided on the sides of the rotor.

The rotor 1 is surrounded like a shell of the housing 3, wherein the housing 3 is also formed of two housing elements 3a and 3b, which are screwed together as well as the rotor parts 1a and 1b and clamped between them receive an 11 for the electric motor.

The rotor 1 is mounted relative to the housing 3 via two slide bearings 12a and 12b so that a minimum air gap 13 results between the electric motor rotor ring 9 and the stator ring 11.

The bearings 12a and 12b are designed as carbide bearings in the form of silicon or aluminum carbide.

On the one hand, carbide is seawater resistant and on the other hand has very good slip properties in combination with water.

In the illustrated embodiment, a sliding bearing 12a or 12b consists of a rotor bearing 14, which is essentially rectangular on its free outer sides, and two essentially radially and axially arranged housing bearings 15, which are arranged on the outer sides of the rotor bearing 14. For small diameters, the rotor bearing 14 and the housing bearing 15 can be made in one piece. For large diameters almost only a multi-part realization of rotor bearing 14 and housing bearings 15 is possible.

Figure 4 shows schematically in perspective view the multi-part design of the housing bearing 15. The housing bearings 15 are formed in cross-section substantially trapezoidal, so that they can be inserted into trapezoidal grooves in the housing. Due to the trapezoidal design, the housing bearings are thus fixed in a form-fitting manner in the housing 3. In addition, these can still be glued.

After fixing these are ground again, so that there is an exact storage despite the individual bearing segments.

Depending on whether a purging on the housing bearing 15 would like to be achieved, the bearing segments 15 as shown in FIG. 4 can be spaced apart by a certain distance d or can be formed on the bearing segments 15.

By the distance d or the grooves thus the bearing segments are flushed steadily, resulting in additional cooling of the bearing and the electric motor.

Figure 5a shows in cross section the rotor bearing 15, which has a trapezoidal recess 16 on its inner side, so that the bearing on a trapezoidal bead on the rotor 1 can be attached.

The positive fixing of rotor bearing 14 and housing bearing 15 is necessary only for large diameters and the formation of the bearing of several bearing segments. Carbide bearings with small diameters only need to be glued.

The bearing segments of the rotor bearing 14 are also advantageously glued in the trapezoidal recess 16 and then ground.

Figure 5b also shows the side view of a bearing segment 14 wherein it can be seen that the sides of the bearing element 14 are each radially rounded.

FIG. 6 shows a partial circle of the bearing elements 14, wherein it can be seen that, due to the rounded portions, laterally on the bearing elements 14, tapered and then again widening gaps S result.

This design of the rotor bearing elements 14, a pumping action is achieved. The liquid, which is located in the gaps S, is pressed outwardly during the rotation by the centrifugal force and thus enters the cavity 17 (see FIG. 3), which arises between the rotor 1 and the housing 3.

If, as in FIG. 4, the housing bearing segments are also spaced apart, the water pumped into the cavity 17 can flow away again between the housing segments segments 15.

Likewise, it is also possible on the housing 3 to provide a bore 18, through which the water pumped via the rotor bearing 14 can emerge again.

For very large drives, an external pump may alternatively be connected to the bore 18, which pumps filtered water into the cavity 17 and thus generates a certain overpressure and rinses the bearings with filtered water.

By producing the bearings exclusively of carbide, in particular silicon carbide, it is possible to provide the bearing unsealed as a water store, whereby a complex sealing is avoided and at the same time excellent cooling is achieved by the water.

The invention is not limited to the illustrated embodiment. Due to the high heat resistance, the carbide bearing can also be used as an air bearing for an air drive.

For the manufacture, it is crucial that both the rotor and the housing can be preassembled and ground, including storage.

Only for installation, the housing must be loosened again and screwed again after the onset of the rotor.

LIST OF REFERENCE NUMBERS

1

rotor

1a, 1b

rotor parts

2

shovel

3

casing

3a, 3b

housing parts

4

Bracket, hydraulic cylinder

5

flange

6

screw

7

cover

8th

management

9

Electric motor rotor ring

10a, 10b

retaining flange

11

stator

12a, 12b

bearings

13

air gap

14

rotor bearing

15

bearing Units

16

Trapezoidal recess

S

column

17

cavity

18

drilling

19

hull

20

opening

21

shaft

22

shell

23

groove

24

bolt

25

Inlet

26

outlet

27

sealing plate

28

sealing bead

29

Lamellenrolo

30

drive

Claims (11)

1. Jet propulsion engine, especially for watercraft, with a rotor (1) on the inside of which blades (2) are arranged and a housing (3) in which the rotor (1) is rotatably mounted, characterised in that the bearing between the rotor (1) and housing (3) comprises sea-watertight carbide.
2. Jet propulsion engine according to claim 1, characterised in that the bearing between the rotor (1) and housing (3) comprises silicon carbide or aluminium carbide.
3. Jet propulsion engine according to claim 1 or 2, characterised in that the bearing between the rotor (1) and housing (3) is made solely of carbide.
4. Jet propulsion engine according to one of claims 1 to 3, characterised in that the bearing is formed by a sliding bearing.
5. Jet propulsion engine according to one of claims 1 to 4, characterised in that the bearing in the rotor (1) and/or the bearing in the housing (3) is made up of several segments.
6. Jet propulsion engine according to claim 5, characterised in that the bearing segments are spaced apart on the rotor or designed such that a pump effect is produced by the centrifugal force.
7. Jet propulsion engine according to claim 6, characterised in that on one side the bearing segments on the rotor (1) and on the opposite side the bearing segments on the housing (3) are spaced apart, so that by means of the pump effect obtained by the spaced apart bearing segments on the rotor (1) a defined through flow is produced.
8. Jet propulsion engine according to one of claims 6 or 7, characterised in that the bearing segments are secured in a form-closed manner onto the housing (3) or rotor (1) and are subsequently adhered.
9. Jet propulsion engine according to one of claims 1 to 8, characterised in that the housing surrounds the rotor like a tube, producing a hollow cavity (17) between the outside rotor (1) and inside housing (3) and an electric ring motor is arranged in said hollow cavity.
10. Jet propulsion engine according to one of claims 1 to 9, characterised in that the bearing between the rotor (1) and housing (3) has a diameter of more than 200 mm, preferably in the region of 200 mm to 2,500 mm.
11. Method for producing a bearing on a jet propulsion engine, especially for watercraft, with a rotor (1) and a housing (3), characterised by the following steps:

    a form-closed securing of bearing segments made of carbide on the rotor,

    b adhesion of the bearing segments to the rotor,

    c grinding of at least two essentially perpendicular bearing surfaces on the bearing segments on the rotor,

    d form-closed securing of bearing segments made of carbide on the housing,

    e adhesion of the bearing segments on the housing and

    f grinding at least two essentially perpendicular bearing surfaces on the bearing segments on the housing.

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