JP2909278B2 - Shaft system of marine contra-rotating propeller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft device for a contra-rotating propeller for a marine vessel, and more particularly, to maintaining the performance of a bearing on the inner propeller shaft, especially on the stern side, even under severe load conditions on the inner propeller shaft. The present invention relates to a shaft system device for a marine contra-rotating propeller having an arrangement configuration of bearings capable of performing the above.

2. Description of the Related Art First, referring to FIG. 4, a shaft device of a conventional contra-rotating marine propeller will be described. An inner propeller shaft 22 directly connected to the main engine 21 drives a rear propeller 23. The inner propeller shaft 22 drives a reversing gear device 26 via an elastic joint 27 that rotates concentrically with the inner propeller shaft 22.

After reversing the direction of rotation, the reversing gear unit 26 transmits a rotational force in a direction opposite to that of the inner propeller shaft 22 to an outer propeller shaft 25 that drives a front propeller 24.

[0003] The inner propeller shaft 22 forms the inner shaft of the contra-rotating propeller shaft system, while the outer propeller shaft 25 forms the outer shaft. The outer propeller shaft 25 is formed by a pair of front and rear outer shaft bearings 28 in the stern tube 31 so that the stern tube 3
1 and is pivotally supported. Also, the inner propeller shaft 2
Reference numeral 2 denotes an outer propeller shaft provided by an inner shaft bearing 29 provided on an inner peripheral portion at a front end of the outer propeller shaft 25 and an inner shaft bearing 30 provided on an inner peripheral portion at a rear end of the outer propeller shaft 25. 25 and the front propeller 24, and is pivotally supported.

[0004]

By the way, the inner shaft bearing 2
Since both 9 and 30 are arranged on the inner peripheral portion of the outer propeller shaft 25, the span between both inner shaft bearings 29 and 30 is larger than the span between the pair of outer shaft bearings 28. For this reason, the deflection of the inner propeller shaft 22 that supports the rear propeller 23 in the overhang state from the rear inner shaft bearing 30 increases, and the relative inclination between the bent inner propeller shaft 22 and the rear inner shaft bearing 30 increases. The corners also increase.

As a result, the bearing load applied to the rear inner shaft bearing 30 locally increases, the thickness of the oil film decreases, and the bearing performance deteriorates. Further, when the ship turns, the force by which the propeller tries to bend the propeller shaft, that is, the shaft force is further increased.
A bearing performance of 0 is significantly reduced.

As a countermeasure against such inconvenience, when the inner shaft bearing is a hydrostatic inner shaft bearing, it is conceivable to increase the supply hydraulic pressure. However, in such a case, the supply hydraulic pressure is increased. This is practical because the power required by the motor that drives the oil pump increases, the oil supply system requires higher pressure resistance, and special considerations for oil leaks are required. Not.

Accordingly, an object of the present invention is to provide a shaft device of a contra-rotating propeller for a marine vessel, in which the bearing performance of the inner shaft bearing is not reduced even if the hydraulic pressure is not increased.

[0008]

[SUMMARY OF] To achieve the above object, shafting system marine contra-rotating propeller of the present invention, the front
A hollow outer propeller shaft that drives the propeller, and the outer
The shaft concentric with the outer propeller shaft inside the propeller shaft
An inner propeller shaft that is supported and drives the rear propeller.
Shaft device of a contra-rotating marine propeller
The device is spaced apart from each other in the axial direction of the outer propeller shaft.
The inner propeller shaft is disposed so that the outer propeller
A pair of front and rear inner shaft bearings that always support the shaft,
Separate from each inner shaft bearing between a pair of inner shaft bearings.
The upper and lower pairs of the inner and outer shaft bearings are arranged at a distance.
While the inner propeller shaft is not bent,
It does not touch the propeller shaft.
When the inner propeller shaft is bent,
The inner propeller shaft is located between a pair of front and rear inner shaft bearings.
The deflection reduces the bearing performance of the pair of front and rear inner shaft bearings.
Within the set limits within the limits
As described above, the inner diameter is larger than the inner diameter of the pair of front and rear inner shaft bearings.
Having at least one disposed within the outer propeller shaft
And one auxiliary inner shaft bearing.

[0009]

In the above-described shaft device for a contra-rotating marine propeller according to the present invention, even if a large shaft force is generated during turning or the like and the inner propeller shaft is largely bent,
The auxiliary inner shaft bearing suppresses the deflection of the inner propeller shaft to a minute limit, and the relative inclination angle between the inner propeller shaft and the bearing on the inner peripheral portion of the front propeller is so large that the bearing performance of the bearing deteriorates. No.

Also, when assembling the shaft system device, since the inner diameter of the auxiliary inner shaft bearing is larger than the inner diameter of the inner shaft bearing at the inner peripheral portion of the front propeller, the work of inserting the inner propeller shaft and the operation of the shaft system are performed. Alignment work, that is, work for establishing axis system alignment is easily performed.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a marine contra-rotating propeller according to an embodiment of the present invention.

As shown in FIG. 1, an inner propeller shaft 2 directly connected to a main engine 1 drives a rear propeller 3. The inner propeller shaft 2 further drives a reversing gear device 7 via an elastic joint 8 that rotates concentrically with the inner propeller shaft 2. After the reversing gear unit 7 reverses the rotation direction, the front propeller 4
Is transmitted to the outer propeller shaft 5 that drives the motor.

The inner propeller shaft 2 forms the inner shaft of the contra-rotating propeller shaft system, while the outer propeller shaft 5
Constitutes the outer shaft. The outer propeller shaft 5 is axially supported by a pair of front and rear outer shaft bearings 9 in the shaft hole of the stan frame so as to pass through the shaft hole of the stan frame. Also, the inner propeller shaft 2 is formed by an inner shaft bearing 10 disposed on the inner peripheral portion at the front end of the outer propeller shaft 5 and an inner shaft bearing 11 disposed on the inner peripheral portion of the front propeller 4. An inner shaft bearing 1 of the inner periphery of the front propeller 4 is provided between the inner shaft bearings 10 and 11 at the inner periphery of the outer propeller shaft 5 while being axially supported through the propeller shaft 5 and the front propeller 4.
At least one auxiliary inner shaft bearing 12 having an inner diameter larger than one inner diameter is provided.

When the propeller is a single propeller, the outer shaft bearing 9 serves as a stern tube bearing of the propeller shaft of the single propeller. However, in the case of a contra-rotating propeller as shown in FIG. , And serves as an outer shaft bearing for the outer propeller shaft 5. On the other hand, the bearing of the inner propeller shaft 2 usually has a front inner shaft bearing 10 disposed on the inner peripheral portion at the front end of the outer propeller shaft 5 and a front propeller 4 due to a structural reason of the shaft system. The shaft is supported by a rear inner shaft bearing 11 disposed on the inner peripheral portion of the shaft.

For this reason, the span between the inner shaft bearings 10 and 11 becomes longer, and when a large shaft force is applied to the inner propeller shaft 2 from the rear propeller 3 during turning of the hull or the like, as shown in FIG. The propeller shaft 2 tries to bend greatly. However, in this embodiment, since at least one auxiliary inner shaft bearing 12 is provided between both inner shaft bearings 10 and 11, the bending of the auxiliary inner shaft bearing 12 prevents the inner propeller shaft 2 from moving. Of the inner prop of the front propeller 4 is suppressed within a small limit to the extent that the bearing performance of the inner shaft bearing does not decrease.

FIG. 3 is a partially enlarged view of FIG. 2 for explaining the operation of the auxiliary inner shaft bearing 12. As shown in FIG. In FIG. 3, the inner diameter 2 × a of the auxiliary inner shaft bearing 12 is larger than the inner diameter 2 × c of the inner shaft bearing 11 at the inner peripheral portion of the front propeller 4, and the difference between the inner diameters is 2 × b.

During normal operation, the inner propeller shaft 2 is supported by the inner shaft bearing 11 and the auxiliary inner shaft bearing 12
Do not touch each other because there is an inner diameter difference of 2 × b. When a large shaft force is applied to the inner propeller shaft 2 during turning of the hull or the like, the inner propeller shaft 2 tends to bend beyond the amount of deflection b corresponding to the difference in inner diameter. However, at this time, the inner propeller shaft 2 is also supported by the auxiliary inner shaft bearing 12, so that its deflection is prevented from being further increased.

[0018]

According to the present invention, a shaft device for a contra-rotating marine propeller according to the present invention is a hollow outer propeller shaft for driving a forward propeller.
And the same outer propeller shaft inside the same outer propeller shaft
The inner prop that is driven concentrically and drives the rear propeller
A shaft device for a marine contra-rotating propeller having a propeller shaft.
Therefore, the coaxial devices are arranged in an axial direction of the outer propeller shaft.
And the inner propeller shaft is
A pair of front and rear inner shafts that are always supported with respect to the outer propeller shaft
And receiving, Uka the respective inner shaft axis between the front and rear pair of inner shaft bearing
A pair of inner shaft bearings, which are arranged at a distance from each other
No deflection in the inner propeller shaft between
The space is not in contact with the same inner propeller shaft.
The inner propeller shaft between the shaft bearings is bent
In this case, the inner press between the pair of front and rear inner shaft bearings
The deflection of the propeller shaft is reduced by the bearing performance of the pair of front and rear inner shaft bearings.
Within the set deflection within the limit that does not lower the performance
The inner diameter of the pair of front and rear inner shaft bearings
Also has a large inside diameter and is arranged inside the outer propeller shaft
And at least one auxiliary inner shaft bearing,
The following effects and advantages can be obtained. (1) even if an attempt bend large inner propeller shaft large shaft forces at the pivot or the like of the hull is generated, the deflection auxiliary inner shaft bearing of the inner propeller shaft, the inner shaft of the inner peripheral portion of the front propeller The bearing performance of the bearing can be suppressed within a limit that does not decrease, and as a result, the performance of the inner shaft bearing at the inner peripheral portion of the front propeller where the bearing load condition is severe is maintained at the desired performance. (2) In the case where the inner shaft bearing is a hydrostatic inner shaft bearing, it is not necessary to increase the oil supply oil pressure, so that the motor drive power increases due to the increase in the oil pump pressure and the oil supply system increases in pressure. No special measures are required . (3) Since the inner diameter of the auxiliary inner shaft bearing is larger than the inner diameter of the inner shaft bearing at the inner peripheral portion of the front propeller, the insertion of the inner propeller shaft and the alignment of the shaft system can be performed when assembling the shaft system device. The establishment operation can be easily performed.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a main part of a shaft device of a contra-rotating marine propeller as one embodiment of the present invention.

FIG. 2 is an operation explanatory view of the shaft system device of FIG. 1;

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a vertical sectional view of a main part of a shaft device of a conventional contra-rotating marine propeller.

FIG. 5 is an operation explanatory view of the shaft system device of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main engine 2 Inner propeller shaft (inner shaft) 3 Rear propeller 4 Front propeller 5 Outer propeller shaft (outer shaft) 6 Flange joint 7 Reversing gear unit 8 Elastic joint 9 Outer shaft bearing 10 Bow side inner shaft bearing 11 Stern side inner shaft Bearing 12 Auxiliary inner shaft bearing 21 Main engine 22 Inner propeller shaft (inner shaft) 23 Rear propeller 24 Front propeller 25 Outer propeller shaft (outer shaft) 26 Reversing gear shaft 27 Elastic joint 28 Outer shaft bearing 29 Inner shaft bearing 30 Stern side inner Shaft bearing 31 Stern tube a Inner radius b Inner radius difference c Inner radius

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-24320 (JP, A) JP-A-61-179099 (JP, U) JP-A-2-21325 (JP, U) (58) Investigation Field (Int.Cl. ⁶ , DB name) B63H 5/10 B63H 23/36 F16C 17/02 F16C 17/26 F16J 15/32 311

Claims (1)

(57) [Claims] 1. A hollow outer propulsion for driving a front propeller.
The propeller shaft and the outer propeller inside the same propeller shaft
The rear propeller is driven concentrically with the propeller shaft.
Shaft system for marine contra-rotating propeller with side propeller shaft
Wherein the coaxial device is in the axial direction of the outer propeller shaft.
The inner propeller shaft
Is a pair of front and rear that always support the outer propeller shaft.
Each inner shaft between the inner shaft bearing and the pair of inner shaft bearings
It is disposed separately from the bearings,
Deflection of the inner propeller shaft between shaft bearings
While it is not in contact with the propeller shaft inside,
Deflection of the inner propeller shaft between the pair of inner shaft bearings
When it occurs, the above-mentioned pair of inner shaft bearings
The deflection of the inner propeller shaft is
The deflection set within the limit that does not lower the bearing performance
Of the pair of inner shaft bearings
With a larger inside diameter than the inside diameter of the outer propeller shaft.
At least one auxiliary inner shaft bearing provided
A shaft device for a contra-rotating propeller for a ship, characterized in that: