JPH0545480B2 - - Google Patents

Description

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

[Conventional technology]

Generally, there is a contra-rotating marine propeller as shown in Fig. 3, in which an outer shaft 2' with a bow propeller 7' at the rear end is attached to a stern frame 1.
1', and the stun frame 1
It is supported by an outer shaft stern bearing 5' and an outer shaft bow bearing 6' which are interposed between the outer shaft 1' and the outer shaft 2'.

In addition, an inner shaft 1' having a stern propeller 8' at its rear end passes through the outer shaft 2' and is disposed concentrically with the outer shaft 2'. It is supported by an inner shaft stern bearing 3' and an inner shaft bow bearing 4' interposed between the shaft 1' and the outer peripheral surface of the shaft 1'. Conventionally, oil-lubricated white metal plain bearings have been used as these bearings 3' and 4'.

These inner shaft 1' and outer shaft 2' are connected to a main engine (not shown) via a reversing device (not shown), so that the propellers 8' and 7' can be rotated in opposite directions. .

On the other hand, an outer shaft stern side sealing device 9'a and an outer shaft bow side sealing device 9'b are provided between the stern frame 11' and the outer shaft 2' on the outboard and inboard sides, respectively, and the inner shaft stern side sealing device Device 1
0'a and an inner shaft bow side sealing device 10'b are provided between the outer shaft 2' and the inner shaft 1' on the outboard side and inboard side, respectively, and these sealing devices 9'a, 9'b , 10'a and 10'b prevent relative axial movement of the inner shaft 1', outer shaft 2' and stan frame 11', respectively, and also prevent the bearings 3', 4', 5' and 6' from moving in the relative axial direction. Designed to prevent lubricant leaks.

Conventionally, in a bearing lubrication device for a marine counter-rotating propeller shaft system as described above, as shown in FIG.
A lubricating oil supply port 12' is provided for supplying lubricating oil between the stan frame 11' and the outer shaft 2',
In the outer shaft 2', a lubricating oil passage portion 13' extends from the outer circumferential surface of the outer shaft 2' near the outer shaft stern side sealing device 9'a to the inner shaft stern side bearing 3' in the outer shaft 2'. The lubricating oil supplied from the lubricating oil supply port 12' flows along the outer peripheral surface of the outer shaft 2' to the bearings 6', 5', the outer shaft stern side sealing device 9'a, and the lubricating oil passage section. 1
3', the lubricating oil is applied along the outer peripheral surface of the inner shaft 1' to the inner shaft stern bearing 3', the inner shaft stern sealing device 10'a, and the inner shaft bow bearing 4'. A passage is constructed.

Further, a lubricating oil discharge passage section 1 that can discharge lubricating oil that has passed through the inner shaft bow side bearing 4' through an oil drain port 15' formed on the bow side of the stern frame 11'.
4' is formed on the outer shaft 2'.

Furthermore, conventionally, a separate lubrication device from the above-mentioned lubrication device is provided for lubrication of the inner shaft bow side seal device 10'b on the bow side, and in this device,
Lubricating oil supplied from a lubricating oil supply port 16' provided on the bow side of the stern frame 11' passes through a lubricating oil passage 18' formed on the outer shaft 2' to the inner shaft bow side seal on the bow side. After lubricating the device 10'b,
A lubricating oil passage is formed such that the lubricating oil is discharged through a lubricating oil passage portion 17' bored in the inner shaft 1' and through an oil drain port 15'.

Therefore, in the conventional marine counter-rotating propeller shaft bearing lubrication device as described above, as shown by arrow A, the lubricating oil flowing from the lubricating oil supply port 12' is
After lubricating the outer shaft bow side bearing 6' and the outer shaft bow side sealing device 9'b on the bow side, the outer shaft 2' is moved to the stern side along the outer peripheral surface of the outer shaft 2', and as shown by arrow B, the outer shaft 2 is lubricated. 'On the stern side of the outer peripheral surface, the inner shaft stern bearing 3' configured as a sliding bearing and the outer shaft stern seal device 9'a on the stern side are lubricated.

Then, as shown by arrow C, the lubricating oil flows into the outer circumferential surface of the inner shaft 1' on the stern side through the lubricating oil passage 13', and the inner shaft 1' on the stern side of the inner shaft bearing 3' and the inner shaft stern seal on the stern side. After passing through the device 10'a, as shown by arrows D and E, it flows into the bow side along the outer peripheral surface of the inner shaft 1 and lubricates the outer shaft bow side bearing 6'.

At this stage, the temperature of the lubricating oil has risen extremely high, and the lubricating oil passes through the outer shaft bow bearing 6'.
Since it is not suitable for continuous lubrication of the inner shaft bow side sealing device 10'b, the lubricating oil is discharged through a lubricating oil drain passage consisting of an oil drain passage section 14' and an oil drain port 15', as shown by arrow F. .

In addition, in order to lubricate the inner shaft bow side sealing device 10'b, as shown by arrow H, a lubricating oil supply port 1 is provided.
The low-temperature lubricating oil supplied from 6' passes through the lubricating oil passage 18' to lubricate the inner shaft bow side seal device 10'b, and then, as shown by arrow G, is provided on the inner shaft 1'. The lubricating oil is discharged from the drain port 15' as shown by arrow F through the lubricating oil passage section 17'.

[Problem that the invention seeks to solve]

However, in the conventional bearing lubrication device for a marine counter-rotating propeller shaft system as described above, the inner shaft 1' and the outer shaft 2', which are structurally extremely heavy, rotate at high speed in opposite directions. An oil film is difficult to form on the inner shaft stern bearing 3' and the inner shaft bow bearing 4', which are sliding bearings interposed between the inner shaft 1' and the outer shaft 2', and this problem is unique to sliding bearings. However, the formation factors of the oil film are the shaft rotation speed, the bearing load (local surface pressure), and the angle of partial contact between the shaft and the bearing (shaft inclination angle), so the range in which hydrodynamic lubrication can be achieved for sliding bearings is limited.

In particular, in a contra-rotating propeller shaft system, the inner shaft 1' is largely deflected due to the overhang from the ship's hull of the stern propeller 8' installed at the rear end of the inner shaft 1'. becomes larger, it tends to be difficult to form an oil film on the inner shaft stern bearing 3' and the inner shaft bow bearing 4', and the lubrication performance of these bearings 3' and 4' deteriorates significantly, causing the inner shaft 1' and Direct contact between the bearings 3' and 4' may cause seizure.

Therefore, it may be possible to increase the diameter of the inner shaft 1' to suppress the increase in the angle of contact and local surface pressure, but in this case, the diameter of the outer shaft 2' must also be increased, and the diameter of the outer shaft 2' must be increased. The entire shaft system becomes larger than necessary to accommodate the inner shaft bearing, which not only increases costs but also adversely affects propeller performance.

The present invention is an attempt to solve the above-mentioned problems, and it is possible to reduce the diameter of the inner shaft to the required minimum diameter while ensuring the lubrication of the inner shaft bearing. It is an object of the present invention to provide a bearing lubrication device for a counter-rotating marine propeller shaft system, which allows the propeller shaft system to be made compact easily and at low cost.

[Means for solving problems]

For this reason, the bearing lubrication device for a contra-rotating marine propeller shaft system of the present invention is provided in a counter-rotating propeller shaft system consisting of an inner shaft and an outer shaft that are provided concentrically with each other at the stern of the ship. An inner shaft stern side bearing for supporting the inner shaft is provided between the peripheral surface and the outer peripheral surface of the inner shaft, and an inner shaft bearing is provided between the front end inner peripheral surface of the outer shaft and the outer peripheral surface of the inner shaft. The inner shaft stern bearing is configured as a self-aligning rolling bearing, and the lubricating oil supply system for the rolling bearing is arranged along the central axis of the inner shaft. It is characterized by being configured with an in-shaft oil supply passage and a lubricating oil acceleration passage that bends from the inner shaft in-shaft oil supply passage to the outer circumferential surface of the inner shaft and reaches the self-aligning roller bearing. .

[Effect]

In the bearing lubrication device for a marine counter-rotating propeller shaft system of the present invention described above, the inner shaft stern bearing is configured as a self-aligning rolling bearing, so the diameter of the inner shaft can be made the required minimum diameter. At the same time, a large amount of lubricant can be accelerated and supplied to the inner shaft stern bearing through the inner shaft internal oil supply passage and lubricant acceleration passage along the center axis of the inner shaft, reducing the friction generated in the self-aligning rolling bearing. As powder is washed away, the bearing can be properly lubricated.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a bearing lubricating device for a contra-rotating marine propeller shaft system as a first embodiment of the present invention, and FIG. FIG. 7 is a longitudinal sectional view showing a bearing lubricating device for a marine contra-rotating propeller shaft system as a second embodiment of the invention.

As shown in FIG. 1, in a marine counter-rotating propeller to which the device of the first embodiment of the present invention is applied, an outer shaft 1 having a bow side propeller 18 at the rear end.
1 is disposed through the stun frame 12,
It is supported by an outer shaft bow side bearing 10 and an outer shaft stern side bearing 13 interposed between the inner peripheral surface of the stern frame 12 and the outer peripheral surface of the outer shaft 11. Of these bearings 10, 13, the outer shaft stern bearing 13 is constructed as a static pressure bearing, and the outer shaft bow bearing 10 is constructed as a normal stern tube bearing.

Further, the inner shaft 3 is provided with a stern side propeller 19 at the rear end and has an inner shaft internal refueling passage 21 along the center axis.
An inner shaft stern side bearing 17 is inserted through the outer shaft 11 and is disposed concentrically with the outer shaft 11, and is interposed between the inner circumferential surface of the rear end of the outer shaft 11 and the outer circumferential surface of the inner shaft 3. An inner shaft bow side bearing 7 is supported by and interposed between the inner circumferential surface of the front end of the outer shaft 11 and the outer circumferential surface of the inner shaft 3.
Supported by These inner shaft stern bearing 17 and inner shaft bow bearing 7 are configured as a self-aligning rolling bearing and a sliding bearing, respectively.

The inner shaft 3 is connected to the inner shaft joint 2 and the intermediate inner shaft 1.
The outer shaft 11 is also connected to a reduction and reversal gear device (not shown) via an outer shaft joint 6 and a hollow shaft 4 (not shown), and these inner shafts 3 and the outer shaft 11 are connected to a marine motor (not shown) via the reduction and reversal gear device, so that the propellers 19 and 18 can be driven to rotate in opposite directions.

On the other hand, an outer shaft stern side sealing device 14 and an outer shaft bow side sealing device 9 are provided between the stern frame 12 and the outer shaft 11 on the outboard and inboard sides, respectively, and the inner shaft stern side sealing device 16 and the inner shaft A bow side sealing device 5 is provided between the outer shaft 11 and the inner shaft 3 on the outboard and inboard sides, respectively. In addition to preventing relative axial movement of the stand frames 12, leakage of lubricating oil in the bearings 7, 10, 13, and 17 is also prevented.

In the device of the first embodiment of the present invention for lubricating the bearings of a marine contra-rotating propeller shaft system as described above, the stern of the inner shaft is lubricated along the central axis of the inner shaft 3 and through the inside of the inner shaft 3. The inner shaft oil supply passage 21 that is formed to reach the side bearing (self-aligning rolling bearing) 17 is connected to the inner shaft oil supply pipe 2 at its bow end.
At the stern end of the inner shaft 3, the lubricating oil acceleration passage 21a bends in the radial direction from the rear end of the inner shaft oil supply passage 21 to the outer peripheral surface of the inner shaft 3 and reaches the bearing 17. The passage 21a is connected to the inner shaft stern side sealing device 16 on the outer peripheral surface of the inner shaft 3.
and inner shaft stern bearing (self-aligning rolling bearing) 17
There is communication between the two. In this way, the lubricating oil flowing into the inner shaft oil supply passage 21 from the inner shaft oil supply pipe 27 is accelerated by the centrifugal force accompanying the rotation of the inner shaft 3 while passing through the lubricant acceleration passage 21a. Since it flows vigorously into the shaft stern bearing 17, the friction powder generated in the inner shaft bearing 17, which is a self-aligning rolling bearing, is washed away, thereby providing sufficient lubrication. In this way, the lubricating oil passes through the bearing 17 and enters the outer shaft oil supply passage 47 between the outer peripheral surface of the inner shaft 3 and the inner peripheral surface of the outer shaft 11.
The water flows through the inner shaft toward the bow side and reaches the inner shaft bow side bearing (sliding bearing) 7 and the inner shaft bow side sealing device 5.

The outer shaft 11 also has a lubricating oil passage portion 22 so as to communicate between the inside of the outer shaft 11 near the inner shaft bow side bearing (sliding bearing) 7 and the outer shaft bow side sealing device 9.
is formed, and the outer shaft bow side sealing device 9
An oil drain pipe 33 is provided, and the oil drain pipe 33 is connected to a lubricating oil tank 30 via a sight glass 32.

This lubricating oil tank 30 is connected to the inner shaft oil supply 27 via a lubricating oil cooler 28 and a lubricating oil pump 29, and provides low-temperature, high-quality lubrication to the inner shaft oil supply passage 21 in the lubricating oil supply system. Supply oil.

On the other hand, an oil supply pipe 25 is provided at the center of the outer shaft stern bearing (static pressure bearing) 13 to supply high-pressure lubricating oil between the inner peripheral surface of the bearing 13 and the outer peripheral surface of the outer shaft 11.
This oil supply pipe 25 is also connected to a high pressure oil tank 42 via a high pressure oil pump 36.

Note that an inner shaft oil supply pipe 27 is connected to this high pressure oil tank 42 through a high pressure oil tank supply pipe 26 which is interposed with a needle valve 39, and these inner shaft oil supply pipes 27 and high pressure oil tank supply pipe 26 are connected to each other. Lubricating oil in a lubricating oil tank 30 is supplied via a pipe 26.

Further, an overflow pipe 43 is provided in the high pressure oil tank 42, and when the lubricating oil in the high pressure oil tank 42 exceeds a predetermined amount, the overflow pipe 43
A drop pipe 31 with a sight glass 32 interposed from 3
The lubricating oil is returned to the lubricating oil tank 30 through the lubricating oil tank 30.

At a position between the outer shaft stern side sealing device 15 and the outer shaft stern side bearing (static pressure bearing) 13, the outer shaft 1
1 is formed with an oil drain hole 23 that communicates between the outside of the outer shaft 11 and the outer shaft internal oil supply passage 47 inside the outer shaft 11, while a lubricating oil drop pipe 24 is opened in the stan frame 12. It is formed by This lubricating oil drop pipe 24 is connected to a lubricating oil tank 30 via a stop valve 37 and a switching flange 38.

The lubricating oil that is supplied to the outer shaft stern side bearing (static pressure bearing) 13 and flows toward the bow side after lubricating the same bearing 13 is applied to the outer peripheral surface of the outer shaft 11 and the stern frame 1.
A lubricating oil supply system is provided to reach the outer shaft bow side bearing 10 through between the inner circumferential surface of the outer shaft and the inner circumferential surface of the outer shaft bow side bearing 10.

In addition, an oil drain pipe 3 is provided at the front end of the stan frame 12.
4 is provided, and the oil drain pipe 34 is connected to a sight glass 32.
It is connected to the lubricating oil tank 30 via.

In addition, the reference numeral 8 in FIG. 1 indicates a boss and a plug;
15 is the rope guard, 20 is the propeller cap,
35 is the air vent pipe, 40 is the rear bulkhead of the engine room, 4
1 indicates the hull.

Since the bearing of the marine counter-rotating propeller shaft system and the lubricating device thereof according to the first embodiment of the present invention are configured as described above, the lubricating oil stored in the lubricating oil tank 30 is transferred to the lubricating oil pump 29 and the lubricating device. The oil is cooled by the oil cooler 28, sent out, and fed to the inner shaft oil supply pipe 27.

In this way, the lubricating oil fed to the inner shaft oil supply pipe 27 flows through the inner shaft oil supply passage 21 of the inner shaft 3 from the bow to the stern, and as described above, the lubricant oil is supplied to the inner shaft oil supply pipe 27 in the lubricant acceleration passage 21a. Accelerated by the centrifugal force accompanying the rotation of the inner shaft 3, it flows to the stern portion of the outer peripheral surface of the inner shaft 3, and the inner shaft stern side sealing device 16 and the inner shaft stern side bearing (self-aligning rolling bearing) 17 are Lubricate. At that time, friction powder generated in the inner shaft bearing 17 as a self-aligning rolling bearing is washed away.
In the bearing 17, the lubricating oil is not heated as much as in conventional plain bearings, and the lubricating oil is heated between the outer circumferential surface of the inner shaft 3 and the inner circumferential surface of the outer shaft 11 while maintaining a low temperature. The oil flows toward the bow through the outer shaft inner oil supply passage 47, and the inner shaft bow side bearing (sliding bearing)
7 and the inner shaft bow side seal device 5,
The lubricating oil flows out to the bow side of the outer peripheral surface of the outer shaft 11 through the lubricating oil passage portion 22, and lubricates the outer shaft bow side sealing device 9 at a relatively low temperature.

After lubrication, the lubricating oil is discharged to the lubricating oil tank 30 through the oil drain pipe 33.

On the other hand, the high pressure oil tank 42 includes the lubricating oil tank 3.
The flow rate of the lubricating oil in the inner shaft is adjusted by a needle valve 39 through an inner shaft oil supply pipe 27 and a high-pressure oil tank supply pipe 26 branched from the inner shaft oil supply pipe. It is supplied and stored in a cooled state.

The cooled lubricating oil stored in the high-pressure oil tank 42 is pressurized by the high-pressure oil pump 36 and fed to the oil supply pipe 25 , and from this oil supply pipe 25 the outer shaft stern side bearing (static pressure bearing) 13 is supplied to

Among the high-pressure lubricating oil that lubricates the bearing 13, the high-pressure lubricating oil that flows toward the bow side along the outer peripheral surface of the outer shaft 11 lubricates the outer shaft bow side bearing 10, and then the high-pressure lubricant oil flows from the oil drain pipe 34. It is discharged into tank 42. Also,
Of the high-pressure lubricating oil, the one that flows toward the stern along the outer peripheral surface of the outer shaft 11 lubricates the outer shaft stern side sealing device 14 and then flows from the oil drain hole 23 into the outer shaft internal oil supply passage 47. It joins the flow of lubricating oil or flows into the lubricating oil drop pipe 24 and is discharged to the lubricating oil tank 30 again.

Note that the inner shaft bow side sealing device 5 has only one seal lip, because if the number of seal lips is two as in the past, cooling will be required and the lubricating oil path will become more complicated. Even if lubricating oil leaks from the seal device 5, since the seal device 5 is located inside the ship, problems such as marine pollution will not occur. and plug 8, the leakage is easily discovered.

As described above, according to the bearing lubrication device for a marine counter-rotating propeller shaft system as the first embodiment of the present invention,
Since a self-aligning rolling bearing is now used as the inner shaft stern bearing 17, the increase in the one-sided contact angle and local surface pressure due to deflection of the inner shaft, which had been a problem when conventionally using sliding bearings, has been avoided. Not only does this eliminate the need for consideration, but the diameter of the inner shaft 3 can be reduced to the required minimum diameter, and by adopting a hydrostatic bearing as the outer shaft stern bearing 13, the diameter of the outer shaft 11 can also be reduced. Since the diameter can be reduced to the minimum diameter that can be equipped with a rolling bearing, the entire counter-rotating propeller shaft system can be constructed easily and compactly at low cost, which can also contribute to improving propeller performance.

In addition, the lubricating oil supply system that lubricates the outer shaft system and the lubricating oil supply system that lubricates the inner shaft system are installed independently, so each bearing and seal device can be supplied with low-temperature, high-quality lubricating oil. This enables the performance of each bearing to be dramatically improved compared to conventional bearings.

In particular, in this embodiment, the lubricating oil flows from the inner shaft oil supply passage 21 along the central axis of the inner shaft 3 to the inner shaft stern side bearing 17 as a self-aligning rolling bearing by bending toward the outer peripheral surface of the inner shaft. In the acceleration passage 21a, the lubricating oil is accelerated by centrifugal force when the inner shaft 3 rotates, so
The friction powder generated in the bearing 17 is sufficiently washed away, and the bearing 17 is properly lubricated.

Next, a description will be given of a bearing lubrication device for a marine counter-rotating propeller shaft system as a second embodiment of the present invention.As shown in FIG.
Although the configuration is almost the same as that of the embodiment, in the second embodiment, a stern tube bearing similar to the conventional one is used as the outer shaft stern bearing 44, whereas in the first embodiment, the outer shaft stern bearing (static A high-pressure oil tank 4 provided to supply high-pressure lubricating oil to the pressure bearing) 13
2. The high-pressure oil pump 36, oil supply pipe 25, etc. are eliminated, and the oil drain hole 23 formed in the outer shaft 11 in the first embodiment is also not provided in the second embodiment.

Moreover, the lubricating oil drop pipe 24 in the first embodiment
In the second embodiment, the outer shaft oil supply pipe 46 is branched from the inner shaft oil supply pipe 27 via a flow meter 45 and a needle valve 39.

Further, the outer shaft oil supply pipe 46 and the outer shaft bow side sealing device 9 include lubricating oil drop pipes 24, 24'.
In addition to being connected so as to communicate with the lubricating oil tank 30 via a stop valve 37 and a switching flange 38, respectively, the oil drain pipes 33 and 34 are connected to the lubricating oil tank 30 by merging in the middle.

In the inner shaft oil supply pipe 27, the outer shaft oil supply pipe 46
Similar to the outer shaft oil supply pipe 46, a needle valve 39 and a flow meter 45 are interposed downstream of the branch point.

Since the bearing lubrication device for a marine counter-rotating propeller shaft system according to the second embodiment of the present invention is configured as described above, the lubricating oil tank 30 passes through the inner shaft oil supply pipe 27 along the central axis of the inner shaft 3. The lubricating oil supplied to the inner shaft internal oil supply passage 21 is supplied to the inner shaft stern side bearing (self-aligning rolling bearing) 17 through the lubricating oil acceleration passage 21a in exactly the same manner as in the first embodiment, Furthermore, after lubricating the inner shaft stern side sealing device 16, the inner shaft bow side bearing (sliding bearing) 7, the inner shaft bow side sealing device 5, and the outer shaft bow side sealing device 9, the oil is discharged from the oil drain pipe 33 to the lubricating oil tank 30. be done.

On the other hand, from the lubricating oil tank 30 to the inner shaft oil supply pipe 27
The lubricating oil supplied to the outer shaft oil supply pipe 46 through the lubrication oil lubricates the outer shaft stern side sealing device 14 and the outer shaft stern side bearing (stern tube bearing) 44, and then the outer shaft 1
The water flows toward the bow side along the outer peripheral surface of the outer shaft bow side bearing 10 and lubricates the outer shaft bow side bearing 10.

After the lubrication, the lubricating oil is transferred to the oil drain pipe 3.
4 and is discharged to the lubricating oil tank 30.

Note that the needle valve 39 installed in the oil supply pipes 27 and 46 is connected to the flow meter 45 and the sight glass 3.
This is to adjust the supply amount of lubricating oil while utilizing 2.

In this way, the second embodiment of the present invention can provide the same effects as the first embodiment.

〔Effect of the invention〕

As described in detail above, according to the bearing lubrication device for a marine contra-rotating propeller shaft system of the present invention, in a contra-rotating propeller shaft system consisting of an inner shaft and an outer shaft provided concentrically with each other at the stern, An inner shaft stern side bearing for supporting the inner shaft is provided between the inner circumferential surface of the rear end of the outer shaft and the outer circumferential surface of the inner shaft, and an inner circumferential surface of the front end of the outer shaft and the outer circumferential surface of the inner shaft are provided. An inner shaft bow side bearing for supporting the inner shaft is provided between the inner shaft and the inner shaft, the inner shaft stern side bearing is configured as a self-aligning rolling bearing, and a lubricating oil supply system for the rolling bearing is provided.
The inner shaft has an internal oil supply passage along the center axis of the inner shaft, and a lubricating oil acceleration passage that bends from the inner shaft internal oil supply passage to the outer circumferential surface of the inner shaft and reaches the self-aligning rolling bearing. The self-aligning system has a simple structure, and takes into consideration the increase in uneven contact angle and local surface pressure due to deflection of the inner shaft, which was a problem when conventionally a sliding bearing was used for the inner shaft on the stern side shaft. By using type rolling bearings, not only is this unnecessary, but the diameter of the inner shaft can be reduced to the required minimum diameter, allowing the entire counter-rotating propeller shaft system to be constructed easily, cost-effectively, and compactly. It became like this,
Moreover, the friction powder that is a problem with the self-aligning rolling bearing as the inner shaft stern bearing can be washed away with the lubricating oil that flows in vigorously from the lubricating oil acceleration passage to properly lubricate the bearing. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a bearing lubrication device for a marine contra-rotating propeller shaft system as a first embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a contra-rotating marine propeller shaft system as a second embodiment of the present invention. FIG. 3 is a vertical cross-sectional view showing a shaft system bearing and its lubricating device; FIG. 3 is a vertical cross-sectional view showing a conventional bearing lubricating device for a marine counter-rotating propeller shaft system. 1...Intermediate inner shaft, 2...Inner shaft joint, 3...Inner shaft, 4...Half-split hollow shaft, 5...Inner shaft bow side seal device, 6...Outer shaft joint, 7...Inner shaft Shaft bow side bearing (sliding bearing), 8...Boss and plug, 9
... Outer shaft bow side sealing device, 10 ... Outer shaft bow side bearing (stern tube bearing), 11 ... Outer shaft, 12 ... Stan frame, 13 ... Outer shaft stern side bearing (static pressure bearing), 14 ...Outer shaft stern side sealing device, 15...
Rope guard, 16... Inner shaft stern side seal device,
17... Inner shaft stern bearing (self-aligning rolling bearing), 18... Bow propeller, 19... Stern propeller, 20... Propeller cap, 21...
Inner shaft internal oil supply passage, 21a, 22... Lubricating oil acceleration passage, 23... Oil drain hole, 24, 24'... Lubricating oil drop pipe, 25... Oil supply pipe, 26... High pressure oil tank supply pipe, 27... Inner shaft oil supply pipe, 28... Lubricating oil cooler, 29... Lubricating oil pump, 30... Lubricating oil tank, 31... Drop pipe, 32... Sight glass, 33, 34... Oil drain pipe , 35... Air vent pipe, 36... High pressure oil pump, 37... Stop valve, 3
8...Switching flange, 39...Needle valve, 40
...Aft bulkhead of engine room, 41...Hull, 42...
High pressure oil tank, 43... Overflow pipe, 44
... Outer shaft stern side bearing (stern tube bearing), 45 ... Flow meter, 46 ... Outer shaft oil supply pipe, 47 ... Outer shaft internal oil supply passage.

Claims (1)

[Claims] 1 In a contra-rotating propeller shaft system consisting of an inner shaft and an outer shaft that are provided concentrically with each other at the stern, the inner shaft is supported between the inner circumferential surface of the rear end of the outer shaft and the outer circumferential surface of the inner shaft. an inner shaft stern bearing that supports the inner shaft, and an inner shaft bow bearing that supports the inner shaft between the inner peripheral surface of the front end of the outer shaft and the outer peripheral surface of the inner shaft, and the inner shaft stern bearing It is configured as a self-aligning rolling bearing, and the lubricating oil supply system for the rolling bearing includes an inner shaft oil supply passage along the center axis of the inner shaft, and a supply line extending from the inner shaft oil supply passage to the outer circumference of the inner shaft. A bearing lubricating device for a contra-rotating marine propeller shaft system, comprising a lubricating oil acceleration passage bent into a plane and reaching the self-aligning rolling bearing.