WO2019166197A1

WO2019166197A1 - Bearing block for a ship drive comprising two propellers which run in opposite directions, and ship drive

Info

Publication number: WO2019166197A1
Application number: PCT/EP2019/052817
Authority: WO
Inventors: Daniel Wolf; Christian Reischl
Original assignee: Zf Friedrichshafen Ag; ZF PADOVA Srl.
Priority date: 2018-03-01
Filing date: 2019-02-06
Publication date: 2019-09-06
Also published as: DE102018203041B4; DE102018203041A1

Abstract

The invention relates to a bearing block (10) for a ship drive (1) with two propellers (2, 3) which run in opposite directions. The bearing block (10) has a first bore (4) for supporting a first propeller shaft (6) and a second bore (5) for supporting a second propeller shaft (7). The second bore (5) runs diagonally to the first bore (4). The invention additionally relates to a corresponding ship drive (1), in which a first and a second propeller (2, 3) can be driven by a common drive motor (30) via a shaft system. The first propeller (2) is arranged on a first propeller shaft (6), and the second propeller (3) is arranged on a second propeller shaft (7). The first propeller shaft (6) runs diagonally to the second propeller shaft (7).

Description

Bearing for a ship propulsion

with two counter-rotating propellers and ship propulsion

The present invention relates to a bearing bracket for a marine propulsion with two counter-rotating propellers according to the preamble of claim 1. Furthermore, the invention relates to a ship propulsion with two counter-rotating propellers according to the preamble of claim 10.

From the prior art it is known that marine propulsion with two propellers driven in opposite directions can achieve a higher efficiency than ship propulsion systems with only one propeller. This is because the turbulence generated by a first propeller and not used for propulsion is partially "neutralized" by the second propeller. Furthermore occurs in ship propulsion systems with two propellers driven in opposite directions no so-called wheel effect, because the supporting torques of the two propellers compensate each other. This improves the maneuverability. The term marine propulsion is understood to mean propulsion systems for smaller vessels such as sport and leisure boats as well as larger, commercially used ships.

From US 5232386 A a marine propulsion is known in which two propellers of a drive motor in opposite directions, i. rotating in opposite directions. The two propellers are driven by a shaft system and a bevel gear arranged in a bearing block. Two coaxial with each other arranged propeller shafts are stored in the bearing block. Such a bearing block is also called Wellenbock. The bearing block supports the part of the ship propulsion arranged outside the hull on the hull of the ship.

The object of the present invention is to provide a bearing block for a marine propulsion with two counter-rotating propellers, which is improved over the prior art, in particular with regard to a simple structure and high efficiency. Furthermore, a corresponding ship propulsion is to be specified. These tasks are performed by a bearing block for a propeller shaft of a

Ship propulsion with two counter-rotating propellers according to claim 1 and solved by a ship propulsion according to claim 10. Advantageous embodiments of the invention are specified in the respective dependent claims.

It is proposed a bearing block for a ship propulsion with two counter-rotating propellers. The bearing block has a first bore for supporting a first propeller shaft and a second bore for supporting a second propeller shaft. In this case, the second bore extends obliquely with respect to the first bore. One of the second bore associated second Bohrungsmittelachse is thus arranged inclined to one of the first bore associated first Bohrungsmittelachse. The Bohrungsmittelachsen the two holes can, for example, at an acute angle to each other. In other words, the second bore may be tilted downwards relative to the first bore by a certain angle. Said angle may be in particular in the range of 10 to 45 degrees. Preferably, the two Bohrungsmittelachsen lie in a common vertical plane, so that the two mutually oblique Bohrungsmittelachsen the two holes intersect at a point. The common vertical plane preferably runs along or parallel to a ship's longitudinal axis. The ship's longitudinal axis runs in a balanced state at standstill of the boat in the longitudinal direction horizontally through the boat hull. The term bore is understood to mean an elongated recess in the bearing block which is suitable for receiving a propeller shaft assigned to it, regardless of how the bore was produced. It may thus be, for example, a resulting in a casting process recess in the bearing block.

The proposed bearing block is particularly suitable for a marine propulsion with a straight shaft system. A straight shaft system is understood to mean a drive arrangement of a ship propulsion system in which a drive train runs straight from a drive shaft of a drive motor to the propeller shaft, that is to say along a common drive axle. A first propeller is mounted in the region of the free end of the first propeller shaft, wherein the free end of the first propeller shaft substantially, that is, apart from its inclination in the vertical direction, is aligned against a main direction of travel of the ship. A second propeller is mounted in the region of the free end of the second propeller shaft, wherein the free end of the second propeller shaft substantially, that is, apart from its inclination in the vertical direction, is aligned in the main direction of travel. In this embodiment, the first propeller is arranged in the main direction of travel behind the bearing block and the second propeller is arranged in the main direction of travel in front of the bearing block. This means that, when traveling in the main direction of travel, the flow is directed from the second propeller towards the first propeller.

The bearing block may have a transmission interior, which is suitable to receive a bevel gear, via which a drive power from the first propeller shaft to the second propeller shaft is transferable. For example, the first propeller shaft may be part of a straight shaft system and the second propeller shaft is driven by the bevel gear via the first propeller shaft. The oblique arrangement of the holes in the bearing block and the two propeller shafts to each other, for example, allows the use of a simply constructed bevel gear with only two bevel gears. In particular, a bevel gear can be used in which the axes of rotation of the two bevel gears are arranged at an acute angle to each other and intersect. This reduces the space requirement and the production cost in comparison to solutions from the prior art. Furthermore, such a higher overall efficiency can be achieved.

Preferably, the transmission interior is sealed by means of sealing elements oil-tight. Thus, in the transmission interior oil lubrication of the bevel gear can be realized, in which the properties of the lubricating oil can be optimized especially for the lubrication and cooling of the bevel gear. Particularly preferably, it can be provided that the bearing block comprises roller bearings for supporting the first and the second propeller shaft, and that said sealing elements are each a part of the rolling bearings. It can be used advantageous rolling bearings, which are sealed at least on one side, namely in each case to the side of the transmission interior. The sealed to the transmission interior bearings themselves can be lubricated with a different lubricant, especially a bearing grease.

In order to protect the components arranged in the bearing block, in particular the roller bearings and the bevel gears, at least one sealing ring can be arranged in each of the first and second bores, which seals the first and second bores outwardly in a watertight manner. Since the bearing block is located below the waterline when used as intended, a watertight seal for the long-term reliable function of the ship propulsion is extremely important.

Guide vanes may be arranged laterally on the bearing block. Such guide vanes can support the deflection of the flow from the second propeller arranged in the main driving direction in front of the bearing block to the first propeller arranged behind the bearing block in the main driving direction. The guide vanes can be designed asymmetrically on the two sides of the bearing block, so that they oppose the whirl caused by the second propeller in the flow little or no resistance.

According to a further preferred embodiment it is provided that the bearing block has a connection plate for attachment to a ship's hull, and that the connection plate has a flat, curved or spherical contact surface for engagement with the ship's hull. The proposed bearing block can be used on differently shaped ship hulls. The bracket can be easily adapted to the particular shape of the hull by selecting the appropriate connection plate and is thus used with little extra effort for a large number of different applications or ship hull shapes.

To support against a ship's hull the bearing block may have a V-shaped fin, for example with a V-shaped through hole. Such a fin can absorb high tilting moments in the transverse direction and thereby similar to a simple, solid finish fin lighter and with less flow resistance.

In order to make the bearing block still usable for further applications, means for fastening a cap can be arranged in the region of the outlet opening of the second propeller shaft, so that the outlet opening can be closed by means of the cap. Such a cap can be screwed for example by means of at least one threaded bore on the bearing block or jammed in the second bore. As a result, the proposed bearing block can be used in ship drives with only one propeller as part of a modular concept. The cap closing the outlet opening is advantageously streamlined and shaped to match the outer shape of the bearing block so that the cap forms a so-called "nose cone" which improves the hydrodynamics of the bearing block and the marine propulsion. The shape and advantageous effect on the water flow of "Nose Cones" are known in the art of conventional ship propulsion systems with only one propeller.

The invention further comprises a ship propulsion system with two counter-propelled propellers, wherein a first and a second propeller can be driven by a common drive motor via a shaft system. The first propeller is arranged on a first propeller shaft and the second propeller on a second propeller shaft, wherein the first propeller shaft is inclined with respect to the second propeller shaft. That is, the first and second propeller shafts are not arranged coaxially and not parallel to each other, as is the case with conventional ship propulsion reciprocating propellers.

In a shaft system, the drive shafts extend from a drive motor to the propeller shaft at least approximately along a common drive axis, so that no deflection or bevel gear between the drive motor and the first propeller shaft are required. The propeller shaft is arranged as an extension of the crankshaft or drive shaft of the drive motor. That is, in the present case, that the first propeller shaft is arranged at least approximately coaxially with the drive shaft of the drive motor. The said drive axle can be inclined at an angle downwards. It then also runs inclined with respect to the water surface. For example, a shaft system has fewer gear stages and bearing points compared to Z drives, POD drives, rear drives, drives with outboard motors or thruster drives. Each gear stage and each bearing point brings a certain loss of power. Therefore, a marine propulsion system with a shaft system is simpler and involves only a very small amount of power loss. Therefore, high efficiency can be achieved.

In the proposed marine propulsion system it is preferably provided that a first bevel gear is arranged on the first propeller shaft, wherein the first bevel gear engages with a second bevel gear arranged on the second propeller shaft. Part of the drive power can be transmitted from the first propeller shaft to the second propeller shaft to the second propeller via the first and second bevel gears. The axes of rotation of the two bevel gears can be arranged at an acute angle to each other and intersect. In conventional ship propulsion systems with two propellers that can be driven in opposite directions, more complex transmissions with more components are used to distribute the drive power to the two propellers. The proposed bevel gear with only two bevel gears is in contrast simpler, so that lower manufacturing costs, less maintenance and higher efficiency can be achieved.

It is preferably provided that the first propeller shaft and the second propeller shaft each extend obliquely with respect to a ship's longitudinal axis. In particular, the first propeller shaft and the second propeller shaft can each be tilted by an angle relative to the ship's longitudinal axis. In this way, a maximum propulsion and efficiency can be achieved because both propeller shafts are each inclined only by a small angle to the water surface and the propulsion vectors thereby have a low vertical component. The ship's longitudinal axis runs in the balanced state at standstill of the boat in the longitudinal direction horizontally, that is parallel to the water surface.

Finally, the present invention includes a marine propulsion with a bearing block as described above. In the following the invention will be explained in more detail with reference to the attached figures. Show

1 shows a schematically illustrated inventive ship propulsion system with a shaft system;

2 shows a section of a ship propulsion system according to the invention with a bearing block shown in simplified form;

FIG. 3 is a sectional view of the plane A - A of FIG. 2; FIG.

Fig. 4 shows a first arrangement of a ship propulsion system according to the invention on a

Hull and

5 shows a second arrangement of a ship propulsion system according to the invention on a ship's hull.

The ship's propulsion system 1 shown in FIG. 1 is arranged in the form of a wave installation in a ship's hull 40, which is shown only partially. In the hull 40, a drive motor 30 is mounted. The drive motor 30 may also be designed as a drive unit and include a transmission for speed adjustment. The shaft system extends from a drive shaft 31 of a drive motor 30 along a common drive shaft 32 to a first propeller shaft 6. The first propeller shaft 6 is thus arranged in an extension of the crankshaft or drive shaft 31 of the drive motor 30. The common drive axle 32 is inclined obliquely downward with respect to a horizontally extending ship's longitudinal axis 33. It runs obliquely to the water surface when the ship is balanced in the calm water. At the free end of the first propeller shaft 6, a first propeller 2 is fixed, which rotates during operation and thus provides for propulsion in the water. The first propeller shaft 6 is supported outside of the hull 40 by means of a bearing block 10. The bearing block 10 is attached to the hull 40. A not shown here Rudder for directional control can be arranged with respect to a main direction of travel 34 behind the first propeller 2 on the hull 40.

FIG. 2 shows a detail of a ship propulsion system 1 according to the invention with the bearing block 10. The bearing block 10 has a first bore 4 for supporting a first propeller shaft 6 and a second bore 5 for supporting a second propeller shaft 7. The second bore 5 extends obliquely with respect to the first bore 4, that is, the second bore 5 is tilted with respect to the first bore 4 by an angle downwards. Consequently, the second propeller shaft 7 mounted in the second bore 5 also extends obliquely with respect to the first propeller shaft 6 mounted in the first bore 4. The axes of rotation 24 and 25 of the first and second propeller shafts 6, 7 enclose an acute angle therebetween.

For the storage of the two propeller shafts 6 and 7 rolling bearings 21, 22, 23 and 24 are provided. The rolling bearings 21 and 22 are arranged in the first bore 4 and provided for mounting the first propeller shaft 6. The rolling bearings 23 and 24 are arranged in the second bore 5 and provided for mounting the second propeller shaft 7.

Part of the drive power is transmitted by a bevel gear 9 from the first propeller shaft 6 to the second propeller shaft 7. The bevel gear 9 is arranged in a transmission interior 8 in the bearing block 10. It consists of a first bevel gear 26 and a second bevel gear 27, said bevel gears 26 and 27 are permanently engaged with each other.

The transmission interior 8 is sealed by means of sealing elements 1 1, 12 oil-tight. The sealing elements 1 1, 12 are executed in this embodiment as part of the rolling bearings 21, 22 and 23. For this purpose, the rolling bearings 21, 22, 23 are each unilaterally, namely on the transmission interior 8 side facing sealed so that the Getriebeeinnenraum 8 is sealed with the bevel gear 9 oil-tight and the bearings 21, 22 and 23 with another lubricant, such as grease , can be supplied. The bearing block 10 may have grease nipples to relubricate the greased areas, in particular the rolling bearings 21, 22, 23, 24. The bearing block 10 may further comprise an oil filler plug and an oil drain plug to change the oil for the bevel gear 9 in the transmission interior 8 can.

In addition, in each case at least one sealing ring 17, 18, 19 is arranged in the first bore 4 and in the second bore 5. These sealing rings 17, 18, 19 seal the first and the second bore 4, 5 waterproof towards the outside.

In the region of an outlet opening 36 of the second propeller shaft 7, means for fastening a cap 37 can be arranged, with which the outlet opening 36 can be closed. The cap 37 is advantageously streamlined and shaped to fit the outer shape of the bearing block, so that the cap 37 forms a so-called "nose cone", which improves the hydrodynamics of the bearing block 10 and the marine propulsion system 1, if the ship propulsion system 1 only with the first propeller shaft. 6 is operated.

In Fig. 3, the laterally arranged on the bearing block 10 vanes 13 and 14 are shown. The vanes 13 and 14 help while driving the flow of the arranged in the main direction of travel 34 in front of the bearing block 10, second propeller 3 to redirect, arranged in the main direction behind the bearing block 10, the first propeller 2.

The bearing block 10 has a connection plate 15 for fastening the bearing block 10 to the hull 40. The connection plate 15 in the present embodiment has a flat contact surface 16 which rests in the mounted state on the hull 40 and is fixed. As can be seen in FIG. 3, the bearing block 10 has a V-shaped fin 35, which is rigidly connected to the connection plate 15. About the V-shaped fin 35 and the connection plate 15, the bearing block 10 is supported on the hull 40 from.

FIGS. 4 and 5 show two different possibilities of arranging the bearing block 10 on the hull 40. For clarification, in each case a vertical calachse 38 and 39 drawn, which is in both arrangements at right angles to the second propeller shaft 7 and the axis of rotation 25.

In the arrangement according to FIG. 4, the vertical axis 38 is also perpendicular to the ship's longitudinal axis 33, so that the axis of rotation 25 of the second propeller shaft 7 runs parallel to the ship's longitudinal axis 33. The bottom of the hull 40 is flat in the region of the bearing block 10 and forms a suitable mounting surface for the connection plate 15 with a flat contact surface 16.

In the arrangement according to FIG. 5, with respect to the arrangement of FIG. 4, both propeller shafts 6 and 7 are tilted with respect to the ship's longitudinal axis 33. The second propeller shaft 7 is tilted downwards relative to the ship's longitudinal axis 33, so that the vertical axis 39 is no longer at right angles to the ship's longitudinal axis 33.

Instead, the vertical axis 39 is inclined at an angle to the exact vertical orientation, so that the second propeller shaft 7 and its axis of rotation 25 are inclined relative to the ship's longitudinal axis 33 downwards. The front, second propeller 3 is thus tilted down and the angle of the first propeller shaft 6 has been reduced relative to the ship's longitudinal axis 33. The angle between the first and second propeller shaft 6 and 7 has not been changed from the arrangement in FIG.

The hull 40 is concavely curved in the region of the bearing block 10 in order to reinforce a downward flow 28, 29, resulting in a higher wake wave. This is desired, for example, in ships or boats that are used for waterskiing. Matching to the concave shape of the hull 40 in the region of the bearing block 10, the connection plate 15 and the contact surface 16 is curved, so that the connection plate 15 and thus the entire bearing block 10 can be fastened securely and reliably to the hull 40. Bezuaszeichen

marine propulsion

first propeller

second propeller

first hole

second hole

first propeller shaft

second propeller shaft

Transmission interior space

bevel gear

bearing block

sealing elements

sealing element

vane

connecting plate

contact area

sealing ring

Rolling

axis of rotation

first bevel gear

second bevel gear

flow

drive motor

drive shaft drive axle

ship's longitudinal axis

Main direction

fin

outlet opening

cap

vertical axis

hull

Claims

claims

1. bearing block (10) for a marine propulsion system (1) with two counter-rotating propellers (2,3), wherein the bearing block (10) has a first bore (4) for supporting a first propeller shaft (6), characterized in that the bearing block (10) has a second bore (5) for supporting a second propeller shaft (7), and that the second bore (5) is inclined with respect to the first bore (4).

2. Bearing block according to claim 1, characterized in that the bearing block (10) has a Getriebeinnenraum (8) which is adapted to receive a bevel gear (9) via which a drive power from the first propeller shaft (6) to the second propeller shaft (7 ) is transferable.

3. bearing block according to claim 2, characterized in that the Getriebeinnenraum (8) by means of sealing elements (11, 12) is sealed oil-tight.

4. Bearing block according to claim 3, characterized in that the bearing block (10) rolling bearing (21, 22, 23) for supporting the first and the second propeller shaft (6, 7), and in that the sealing elements (11, 12) each one Part of the rolling bearings (21, 22, 23) are.

5. Bearing block according to one of the preceding claims, characterized in that in the first and the second bore (4, 5) in each case at least one sealing ring (17, 18, 19) is arranged, so that the first and the second bore (4, 5 ) are watertight sealed to the outside.

6. Bearing block according to one of the preceding claims, characterized in that laterally on the bearing block (10) guide vanes (13, 14) are arranged to the deflection of the flow of the, in the main direction in front of the bearing block (10) arranged second propeller (3 ) To support, in the main direction of travel behind the bearing block (10) arranged first propeller (2).

7. Bearing block according to one of the preceding claims, characterized in that the bearing block (10) has a connection plate (15) for attachment to a ship sleeve (40), and that the connection plate (15) has a flat, curved or spherical contact surface (16) for engagement with the hull (40).

8. Bearing block according to one of the preceding claims, characterized in that the bearing block (10) has a V-shaped fin (35) for support against a ship's hull (40).

9. Bearing block according to one of the preceding claims, characterized in that in the region of an outlet opening (36) of the second propeller shaft (7) means for fixing a cap (37) are arranged, with which the outlet opening (36) is closable.

10. Ship propulsion (1) with two propellers (2, 3) which can be driven in opposite directions, wherein a first and a second propeller (2, 3) can be driven by a common drive motor (30) via a shaft system, wherein the first propeller (2) a first propeller shaft (6) is arranged, wherein the second propeller (3) on a second propeller shaft (7) is arranged, characterized in that the first propeller shaft (6) with respect to the second propeller shaft (7) extends obliquely.

11. Vessel propulsion system according to claim 10, characterized in that a first bevel gear (26) on the first propeller shaft (6) is arranged, and that the first bevel gear (26) arranged with a on the second propeller shaft (7), second bevel gear ( 27) is engaged.

12. Vessel propulsion system according to claim 10 or 11, characterized in that the first propeller shaft (6) and the second propeller shaft (7) each extend obliquely with respect to a ship's longitudinal axis (33).

13. Ship drive according to one of claims 10 to 12, characterized in that the ship's drive (1) comprises a bearing block (10) according to claims 1 to 9.