JPH0557958B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lubricating device for a bearing in a propeller shaft system of a counter-rotating marine propeller.

[Prior Art] In general, in ordinary single-shaft ships, when oil lubrication by sliding bearings cannot be achieved, especially when the weight of the propeller is large and the bearing surface pressure is extremely high, or because of low rotation of the propeller shaft, etc. A hydrostatic bearing as shown in is used.

That is, a propeller shaft 1' having a propeller 5' attached to its rear end is disposed through a stern frame 6' and is supported by a bearing bush 2' press-fitted into the stern frame 6'. A bearing metal (mainly white metal) 3' is provided on the inner periphery of this bearing bush 2'.
A pocket 8' is formed at the lowermost end of the inner circumferential surface, and a hydrostatic bearing is constructed by supplying high-pressure lubricating oil from a high-pressure oil pump (not shown) to the pocket 8' through an oil supply pipe 7'. It is becoming more and more common.

The propeller shaft 1' is connected to a propulsion motor (not shown) and rotationally driven by the motor.

Further, the reference numeral 4' in the figure indicates a sealing device.

According to such a hydrostatic bearing, high-pressure lubricating oil is supplied from the pocket 8' at the lowest end of the inner circumferential surface of the bearing bushing 2', where the weight of the propeller 5' causes the propeller shaft 1' to bend and cause uneven contact. is supplied, the propeller shaft 1' is forcibly floated by the lubricating oil, and lubrication is performed.
This prevents problems such as uneven contact.

Hydrostatic bearings as described above have conventionally been applied to marine counter-rotating propeller shaft systems. This is to establish a counter-rotating bearing between the inner and outer shafts that rotate at a constant speed, where it is difficult to form an oil film even in a very low-speed one-sided contact state. In a contra-rotating propeller shaft system, as shown in FIG.
A tubular outer shaft 12' supported in the outer shaft 12' and an inner shaft 11' supported in the outer shaft 12' are provided, and the inner shaft 11' and the outer shaft 12' are rotationally driven in mutually opposite directions. Ru. In such a contra-rotating propeller shaft system, a lubricating oil passage 13' is formed in the inner shaft 11' to introduce high-pressure lubricating oil from an unillustrated hydraulic source, and the lubricating oil passage 13' is connected to the inner shaft 11'. The static pressure is reduced by communicating with a plurality of holes 14' formed radially in the inner shaft 11', and by tightening small hole screws 15' having an orifice restricting function into the openings of these holes 14' on the outer periphery of the inner shaft 11'. bearings are configured. Here, in FIG. 3, illustration of a bearing metal and a bearing bush that constitute a part of the hydrostatic bearing is omitted.

In such a hydrostatic bearing, high-pressure lubricating oil is supplied between the inner shaft 11' and the outer shaft 12' from a hydraulic source (not shown) via the lubricating oil passage 13' and the hole 14', and the bearing is The lubrication takes place as it is formed.

Note that normally, the inner shaft 11' and the outer shaft 12' are
As shown in the figure, there is a high possibility that contact will occur at the bottom due to deflection, so it is required to reliably supply high-pressure lubricating oil to the vicinity of this bottom. Therefore, a plurality of holes 14' are formed radially, and an extremely large amount of lubricating oil is supplied.

[Problem that the invention seeks to solve]

However, in the conventional bearing lubrication device for marine contra-rotating propellers as described above, the inner shaft 11' is forcibly floated by the force of high-pressure oil.
If the supply of high pressure oil stops even for a short time, the inner shaft 1
1' and the outer shaft 12'. The supply of high-pressure oil is generally carried out by a high-pressure oil pump driven by an electric motor, and if the regular and auxiliary generators on a ship stop at the same time for some reason, the ship's power supply will be lost and the high-pressure oil will be turned off. The pump also stops. Therefore, even within a short period of time until the emergency generator is activated, the bearings may seize, making navigation impossible.

The present invention aims to solve these problems by activating the emergency generator after the ship loses power and temporarily supplying high-pressure oil until the ship's power is restored (usually for about 1 minute). be able to supply
An object of the present invention is to provide a bearing lubrication device for a counter-rotating marine propeller, which reliably prevents seizure of the bearing and ensures the safety of the bearing.

[Means for solving problems]

For this reason, the bearing lubricating device for a counter-rotating marine propeller of the present invention has an inner shaft, a bearing bush disposed on the outer periphery of the inner shaft, and a co-bearing bush in a counter-rotating propeller shaft system provided at the stern of the ship. It has a static pressure bearing consisting of a bearing metal provided in the inner shaft, and a tubular outer shaft arranged around the outer periphery of the static pressure bearing, and high pressure lubricating oil is supplied to the static pressure bearing through the inside of the inner shaft. The lubricating oil supply system includes a lubricating oil supply system that supplies high-pressure lubricating oil to the pressure bearing, and the lubricating oil supply system includes a lubricating oil pump that discharges high-pressure lubricating oil, and a high-pressure oil supply pipe that extends from the discharge port of the lubricating oil pump to the hydrostatic bearing. In addition, it is characterized in that it is equipped with an accumulator that is connected to an emergency oil supply pipe branching from the same high-pressure oil supply pipe and capable of discharging high-pressure lubricating oil.

[Effect]

In the bearing lubrication system for a marine counter-rotating propeller of the present invention described above, high-pressure lubricating oil is discharged from the accumulator from the time when the ship's power is lost until the emergency generator is activated, and this lubricating oil is used for emergency use. It is supplied to the hydrostatic bearing via the oil supply pipe and high pressure oil supply pipe.

〔Example〕

Hereinafter, a bearing lubricating device for a contra-rotating marine propeller as an embodiment of the present invention will be explained with reference to the drawings. FIG. 1 is a schematic longitudinal sectional view thereof;
As shown in the figure, in a marine counter-rotating propeller to which the device of this embodiment is applied, a tubular outer shaft 2 having a front propeller 4 at its rear end is disposed to pass through a stern frame 16. , a bow side outer shaft bearing 12 and a stern side outer shaft bearing 13 interposed between the inner circumferential surface of the stun frame 16 and the outer circumferential surface of the outer shaft 2.
Supported by Both of these bearings 12 and 13 are configured as normal stern tube bearings.

Further, an inner shaft 1 having a rear propeller 3 at its rear end and having an inner shaft oil supply passage 18 passes through the outer shaft 2 and is disposed concentrically with the outer shaft 2, and is arranged at the rear end of the outer shaft 2. The stern inner shaft bearing 14 is interposed between the inner circumferential surface of the front end of the outer shaft 2 and the outer circumferential surface of the inner shaft 1. It is supported by a bow-side inner shaft bearing 11 installed therein.

These inner shaft bearings 11 and 14 both have bearing bushes 11a and 14 mounted on the outer periphery of the inner shaft 1.
a and a bearing metal (not shown) provided on the outer periphery of each bearing bush 11a, 14a.

The inner shaft 1 is connected to a reversing device (not shown), and the outer shaft 2 is also connected to a reversing device (not shown) via an outer shaft joint 10 and a split hollow shaft 9. The shaft 2 is connected to a main engine (not shown) via the reversing device, and is configured to rotate the propellers 3 and 4 in opposite directions.

The outer shaft sealing devices 6 and 7 are provided to close the gaps between the stern frame 16 and the outer shaft 2 on the outside and inside the ship, respectively, and the inner shaft sealing devices 5 and 8 are installed on the ship, respectively. The bearing bushes 14a and 11a of the inner shaft bearings 14 and 11 on the outside and inside the ship are provided at one end side to close the gap between the outer shaft 2 and the inner shaft 1, and these sealing devices 5 and 8 are provided. ,
In addition to preventing relative axial movement of the outer shaft 2, inner shaft 1, and stand frame 16, the bearing 1
1 to 14 to prevent leakage of lubricating oil.

In the device of this embodiment for lubricating the bearings of the marine contra-rotating propeller shaft system as described above, as shown in FIG. , a high-pressure oil supply pipe 2 is connected to the bow end thereof via a rotary joint (not shown).
5, and in the vicinity of the inner shaft bearings 11, 14, the inner shaft 1 is connected to the bearing bushes 11a, 1
A large number of oil supply holes 19 are formed radially across 4a and are connected to oil supply holes 19 that communicate with the outer periphery of a bearing metal (not shown).

Further, the high-pressure oil supply pipe 25 is connected to a discharge port of a high-pressure oil pump 23 serving as a lubricating oil pump that discharges high-pressure lubricating oil from the lubricating oil tank 22, and the high-pressure lubricating oil from the high-pressure oil pump 23 is It passes through the oil supply pipe 25, the inner shaft internal oil supply passage 18, and the oil supply hole 19 to reach the inner shaft bearings 11 and 14 as static pressure bearings.

Furthermore, in this embodiment, an accumulator 27 is connected to an emergency oil supply pipe 26 branching from the high pressure oil supply pipe 25 . This accumulator 27 stores lubricating oil at a required pressure so that high-pressure lubricating oil can be discharged in an emergency.
During normal operation, lubricating oil flows into the accumulator 27.
Prada 27 inside the same accumulator 27
A suitable amount is always stored against the gas pressure inside a.

In this embodiment, the above-mentioned lubricating oil pump 23, high-pressure oil supply pipe 25, inner shaft internal oil supply passage 18, oil supply hole 1
9. Emergency oil supply pipe 26 and accumulator 27
A lubricating oil supply system is constructed from these components.

Note that the outer shaft 2 is located near the space between the bow side outer shaft bearing 12 and the outer shaft sealing device 7 (that is, the inner shaft bearing 1
1 and 14 (on the other end side of each of the bearing bushes 11a, 14a), an oil drain hole 20 that connects the inside and outside of the outer shaft 2 and allows lubricating oil to be discharged from the gap between the outer shaft 2 and the inner shaft 1. In addition to this, a seal is formed near the bow side outer shaft bearing 12 and the outer shaft sealing device 7.
An oil drain pipe 21 is provided for discharging lubricating oil from the gap between the outer shaft 2 and the stand frame 16, and this oil drain pipe 21 is connected to a lubricating oil tank 22.

In addition, the inner peripheries of the bearing bushes 11a and 14a in the inner shaft bearings 11 and 14 are provided with lubricating oil that has flowed out from the outside of the bearing metal towards the inner shaft seal device 8 or 5 and is guided to the oil drain hole 20 side. for,
A plurality of oil drain grooves 11b and 14b are each formed.

In FIG. 1, reference numeral 15 indicates a rope guard, 17 indicates a rear bulkhead of the engine room, and 24 indicates a check valve.

Since the bearing lubricating device for a marine counter-rotating propeller as an embodiment of the present invention is configured as described above, during normal operation of the high-pressure oil pump 23, the lubricating oil stored in the lubricating oil tank 22 is The oil is pressurized by the pump 23 and sent out, and is fed from the high-pressure oil supply pipe 2 into the inner shaft internal oil supply passage 18 of the inner shaft 1 . At this time, the lubricating oil is also fed to the accumulator 27 via the emergency oil supply pipe 26, and is stored in an appropriate amount in response to the gas pressure inside the bladder 27a in the accumulator 27.

In this way, the high-pressure lubricating oil supplied to the oil supply passage 18 flows from the bow to the stern within the oil supply passage 18, and flows through the numerous oil supply holes 19 to the bearing bushes of the inner shaft bearings 11 and 14. It flows out to the outer periphery of 11a and 14a, and lubricates these inner shaft bearings 11 and 14.

Then, the bearing bush 1 of the inner shaft bearings 11 and 14
After the high-pressure lubricating oil supplied to the outer peripheries of 1a and 14a lubricates these inner shaft bearings 11 and 14,
There are two types: one that flows out toward the inner shaft sealing device 8, 5 at one end of each bearing bush 11a, 14a, and one that flows out toward the other end of the bearing bush 11a, 14a.

Here, the lubricating oil that has flowed out to the other end side of the latter bearing bushes 11a, 14a passes through the gap between the outer shaft 2 and the inner shaft 1, and enters the oil drain hole 20 formed in the outer shaft 2.
and is discharged to the outside of the outer shaft 2.

In addition, the lubricating oil that has leaked into the former sealing devices 5, 8 lubricates the same sealing devices 5, 8, and then passes through oil drain grooves 11b, 14b formed in the inner circumferences of the bearing bushes 11a, 14a. Bearing bush 11
Since this lubricating oil is guided to the other end side of a, 14a, this lubricating oil is also discharged from the oil drain hole 20 to the outside of the outer shaft 2 together with the latter lubricating oil.

The lubricating oil discharged to the outside of the outer shaft 2 from the gap between the outer shaft 2 and the inner shaft 1 as described above lubricates the outer shaft sealing device 7 and the outer shaft bearing 12, and then lubricates it through the oil drain pipe 21. The oil is discharged to the oil tank 22.

On the other hand, in the unlikely event that the ship's power supply was lost, the high-pressure oil pump 2
3 stops, high-pressure lubricating oil is supplied from the accumulator 27 from the time the power is lost until the emergency generator is activated and the high-pressure oil pump 23 is restarted.
The oil is supplied to the inner shaft bearings 11 and 14 as static pressure bearings through the emergency oil supply pipe 26, the high pressure oil supply pipe 25, the inner shaft internal oil supply passage 18, and the oil supply hole 19, respectively.

That is, when the supply of lubricating oil from the high-pressure oil pump 23 is interrupted in the accumulator 27,
The bladder 27a in the accumulator 27 is expanded by the gas inside, and the lubricating oil having the required pressure is discharged from the accumulator 27. Here, the capacity of the accumulator 27 is the amount of lubricating oil required until the emergency generator is activated, the onboard power supply is restored, and the high-pressure oil pump 23 is restarted to supply high-pressure oil. Nippon Kaiji Kyokai rules require that the emergency generator restore the ship's power supply within 45 seconds, so approximately one minute is required. Of course, this time can be set longer by increasing the capacity of the accumulator 27.

As described above, according to the bearing lubrication device for a contra-rotating marine propeller of the present embodiment, after the loss of onboard power, the emergency generator is activated and the onboard power is restored (the high-pressure oil pump 23 is restarted). , Accumulator 2
High pressure oil from 7 to inner shaft bearing 11 as a static pressure bearing,
14, these inner shaft bearings 11,
14 seizure can be reliably prevented, and the safety and reliability of the hydrostatic bearing can be greatly improved.

Furthermore, since the high-pressure lubricating oil between the inner shaft 1 and the outer shaft 2 is reliably discharged,
It is now possible to use static pressure bearings as the inner shaft bearings 11 and 14 without causing damage to the seal devices 5 and 8, and the inner shaft bearings 11 and 14 always maintain the one-sided contact angle and bearing angle (even during low speed rotation). It becomes possible to form an oil film regardless of the load.

Therefore, seizure due to uneven contact, etc. can be reliably prevented, and the lubrication performance in the shaft system of the counter-rotating propeller is improved. In addition, there is no need to increase the shaft diameter of the inner shaft 1 in order to improve uneven contact, and the shaft diameter can be kept below the rule diameter, so the entire counter-rotating propeller shaft system can be easily and cost-effectively It can be constructed compactly and at low cost, and can also contribute to improving propeller performance.

In addition, in this embodiment, the bearing bushes 11a, 1
4a on the outer periphery of the inner shaft 1 and the same bearing bush 11.
A hydrostatic bearing is used to supply lubricating oil to the outer periphery of a and 14a, but a bearing bushing is attached to the inner periphery of the outer shaft 2 to supply lubricating oil to the inner periphery of the bearing bush. The present device is similarly applicable to hydrostatic bearings.

〔Effect of the invention〕

As detailed above, according to the bearing lubrication device for a counter-rotating marine propeller of the present invention, in the contra-rotating propeller shaft system provided at the stern, the inner shaft and the It is equipped with a static pressure bearing consisting of a bearing bush and a bearing metal provided on the bearing bush, and a tubular outer shaft disposed around the outer circumference of the static pressure bearing, and high-pressure lubricating oil is supplied to the inside of the inner shaft. The lubricating oil supply system includes a lubricating oil pump that discharges high-pressure lubricating oil, and a lubricating oil supply system that supplies high-pressure lubricating oil to the hydrostatic bearing from the discharge port of the lubricating oil pump. It has a simple structure, consisting of a high-pressure oil supply pipe that connects to an emergency oil supply pipe that branches from the same high-pressure oil supply pipe and is equipped with an accumulator that can discharge high-pressure lubricating oil. Even if the hydrostatic bearing is lost, high pressure oil is supplied from the accumulator to the hydrostatic bearing until the emergency generator is started and the ship's power is restored, ensuring that the hydrostatic bearing does not seize. This allows hydrostatic bearings to be employed in counter-rotating propeller shaft systems with sufficient safety and reliability.

In addition, by using hydrostatic bearings, the diameter of the inner shaft can be kept below the rule diameter, making it possible to easily configure the entire counter-rotating propeller shaft system in a compact manner at low cost, improving propeller performance. There is also the advantage of significantly improving

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view showing a bearing lubricating device for a contra-rotating marine propeller as an embodiment of the present invention, and FIG. 2 is a vertical sectional view showing a hydrostatic bearing in an ordinary single-shaft ship. FIG. 3 is a cross-sectional view showing a main part of a conventional bearing lubricating device for a counter-rotating marine propeller using a hydrostatic bearing. 1...Inner shaft, 2...Outer shaft, 3...Rear propeller, 4...
Front propeller, 5... Seal device for inner shaft, 6, 7...
Seal device for outer shaft, 8... Seal device for inner shaft, 9...
2-split hollow shaft, 10...outer shaft joint, 11...bow side inner shaft bearing (static pressure bearing), 11a...bearing bush,
11b...Drain groove, 12...Bow side outer shaft bearing (stern tube bearing), 13...Stern side outer shaft bearing (stern tube bearing), 1
4... Stern side inner shaft bearing (static pressure bearing), 14a... Bearing bush, 14b... Oil drain groove, 15... Rope guard, 16... Stun frame, 17... Rear bulkhead of engine room, 18... Oil supply passage in inner shaft, 19...Oil supply hole, 2
0... Oil drain hole, 21... Oil drain pipe, 22... Lubricating oil tank, 23... High pressure oil pump as a lubricating oil pump,
24... Check valve, 25... High pressure oil supply pipe, 26... Emergency oil supply pipe, 27... Accumulator, 27a... Bladder.

Claims (1)

[Claims] 1. In a counter-rotating propeller shaft system installed at the stern, a hydrostatic bearing consisting of an inner shaft, a bearing bushing provided on the outer periphery of the inner shaft, and a bearing metal provided on the bearing bushing, It is equipped with a tubular outer shaft disposed around the outer circumference of the pressure bearing, and a lubricant supply system that supplies high-pressure lubricating oil to the hydrostatic bearing via the inside of the inner shaft. The system includes a lubricating oil pump that discharges high-pressure lubricating oil,
It is equipped with a high-pressure oil supply pipe leading from the discharge port of the lubricating oil pump to the above-mentioned hydrostatic bearing, and an accumulator that is connected to an emergency oil supply pipe branching from the high-pressure oil supply pipe and capable of discharging high-pressure lubricating oil. A bearing lubricating device for a marine contra-rotating propeller, characterized by: