JP2692239B2 - Contra-rotating propeller device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a contra-rotating propeller device for a ship, which is capable of moving the peak of the vibration torque of a shaft system and is capable of operating in a low speed rotation range. It was possible.

[Prior Art] A contra-rotating propeller device has been developed in order to improve the propulsion efficiency of a ship. For example, as shown in FIG. 5, an inner shaft 2 and an outer shaft 3 supported by a stern tube bearing 1 are used. Propellers 5 and 6 are attached to each end of the configured counter rotating shaft 4,
The power from the main engine 7 is transmitted to the counter-rotating shaft 4 via the reversing gear device 8, and the two propellers 5 and 6 are rotationally driven in the opposite directions at substantially equal rotational speeds to obtain thrust. .

In such a counter-rotating propeller device, the power transmission system including the main engine 7 of the diesel engine and the two propellers 5 and 6 constitutes a vibration system, and vibration occurs due to the explosion of the diesel engine and the power transmission Resonance occurs at the natural frequency of the system, and a peak of vibration occurs.

Therefore, when a low-speed diesel engine is used as the main engine 7, as shown in FIG. 6, the vibration torque A has a high peak B within the normal operating speed range of the engine. Even if the peak B of the torque A is present, if these magnitudes are smaller than the so-called average driving torque C transmitted for driving the two propellers 5 and 6, there is no problem.

However, in the power transmission system including the double-reversal propeller device, the reversing gear device 8 almost eliminates the driving force from the main engine 7.
Since the propellers 5 and 6 are driven by being distributed in 1/2 size, the average drive torque C is also approximately 1/2 of the size of each shaft 2 and 3 of the contra-rotating shaft 4 while vibration is generated. Since the torque A has a value of 100% as it is in the gear train of the reversing gear device 8, the vibration torque A exceeds the average drive torque C.

If the vibration torque A exceeds the average drive torque C in this way, the power transmission system including the propellers 5 and 6 and the main engine 7 will be adversely affected by vibration such that durability is reduced and reliability is reduced. At the same time, chattering, which is a phenomenon in which teeth are struck in the gear train of the reversing gear device 8, may occur, resulting in damage to the teeth.

Therefore, continuous use is prohibited in the range of the rotation speed of the main engine 7 where the vibration torque A exceeds the average drive torque C. A so-called continuous use prohibited range D of the engine rotation speed is set.

However, when the so-called continuous use prohibited range D of the engine speed is set, it is usually impossible to operate the main engine 7 in the low speed range, and the minimum ship speed becomes large, so that the ship is at a slow speed (Dead Slow) when entering or leaving the port. This causes inconvenience in maneuvering that it cannot be moved.

As a countermeasure for this, an elastic joint is provided in the input portion of the reversing gear device 8 to reduce the natural frequency,
As shown in FIG. 5, a clutch 9 is provided between the input part and the output part of the reversing gear device 8 to intermittently transmit the driving force to one shaft (for example, the outer shaft 3) of the double reversing shaft 4. Then, it has been proposed to change the mass of the drive system (see JP-A-63-93698).

[Problems to be Solved by the Invention] However, in the case of interposing an elastic joint to lower the natural frequency, the natural frequency of the vibration system does not decrease so much and the range of the normal rotation speed is still maintained. There is a problem that the peak B of the vibration torque A exists.

Further, when transmitting large horsepower and high torque with an elastic joint, the outer shape of the elastic joint becomes huge, which makes manufacture and mounting difficult.
There is a limit to the application of the counter-rotating propeller device to ships up to PS and 150 rpm, and there is a problem that it cannot be applied to ships equipped with a large horsepower main engine.

On the other hand, even when the clutch 9 is provided so as to change the mass of the drive system by intermittently transmitting the driving force to one of the counter-rotating shafts 4, if the large horsepower and the high torque are transmitted, the durability of the clutch 9 is reduced. There is a problem with sex.

Further, when the counter-rotating propeller device is constructed using a wet multi-plate clutch, which is generally known as a clutch for transmitting high horsepower and high torque, abrasion powder from the clutch disc enters the gear train and bearings. There is also the problem of shortening the life of these.

The present invention has been made in view of the problems of the prior art, and provides a contra-rotating propeller device that can be driven with a large horsepower and a high torque and that can be operated at a very low speed required for marine vessel maneuvering. Is what you are trying to do.

[Means for Solving the Problems] In order to solve the problems of the above-described conventional technology, the counter-rotating propeller device of the present invention transmits the driving force of the main engine through a power distribution mechanism to coaxially move the two front and rear propellers. In the counter-rotating propeller device driven in reverse with each other, the power distribution mechanism is composed of a planetary gear mechanism including two sun gears and a planetary gear supported by a rotatable carrier. The present invention is characterized in that braking means is provided which can restrain the rotation to reversely transmit the driving force and allow the carrier to idle to reduce the mass of the vibration system.

[Operation] According to this counter-rotating propeller device, the power distribution mechanism for reversing drive is composed of the planetary gear mechanism, one of the two front and rear propellers is directly connected to the main engine, and the other is between the two sun gears. The power transmission is carried out by means of which the carrier supporting the planetary gears arranged between the two sun gears can be rotated, and the rotation of this carrier can be restrained by the braking means. In order to function as a contra-rotating propeller, the carrier is allowed to idle and the propeller is driven independently to reduce the mass of the power transmission system to lower the resonance point and reduce the rotation speed. It is designed to enable the navigation of.

Therefore, the operation of the contra-rotating propeller can be controlled by fixing and releasing the carrier by the braking means, and the large horsepower,
High torque power transmission can be easily performed.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

1 to 3 relate to an embodiment of the counter-rotating propeller device of the present invention. FIG. 1 is a vertical sectional view in which a braking means is omitted, FIG. 2 is a plan view of a braking means portion, and FIG. In Fig. 1
It is a III-III arrow line view.

This counter-rotating propeller device 10 is provided with two propellers 11 and 12 in which blades having pitches opposite to each other are formed. These propellers 11 and 12 are coaxially arranged one behind the other and rotate about the same as each other. It is designed to drive in the opposite direction by a number to generate thrust.

The contra-rotating shaft 13 is used to drive these two propellers 11 and 12 in the opposite directions on the same axis, and the stern side propeller 11 is connected to the inner shaft 14 of the central portion and is arranged on the outer periphery of the inner shaft 14. The bow-side propeller 12 is connected to the tubular outer shaft 15.

This counter-rotating shaft 13 is rotatable by supporting the outer circumference of the outer shaft 15 by a stern tube bearing 17 attached to the hull 16, and is interposed between the inner shaft 14 and the outer shaft 15. The bearing 18 allows the inner shaft 14 and the outer shaft 15 to rotate in mutually opposite directions.

Further, a thrust pad 20 is installed in the boss of the bow side propeller 12 so as to sandwich a thrust collar 19 provided on the inner shaft 14 from the front and rear, and the thrust of the bow side propeller 12 is inserted through the thrust collar 19 inside. In addition to being transmitted to the shaft 14, the thrust of the stern side propeller 11 is also directly transmitted to the inner shaft and is collectively supported by the thrust bearing built in the main engine 21.

Further, a seal device 22 is provided in a partition wall portion of the hull 16 through which the counter-rotating shaft 13 penetrates, and is in a liquid-tight state.

A power distribution mechanism 23 is provided between the counter-rotating shaft 13 and the main engine 21 in order to distribute and reversely transmit the driving force from the main engine 21 via the counter-rotating shaft 13.

The power distribution mechanism 23 is composed of a planetary gear mechanism, and has a sun gear 24 composed of an external gear at the center, a sun gear 25 composed of an internal gear at the outer periphery, and these two sun gears 24. 2S-C (star type) planetary gear mechanism that is formed between a planetary gear 27 and a planetary gear 27 mounted on a carrier 26.

The carrier 26 to which the planetary gear 27 is attached is formed in a disk shape so as to be freely rotatable without being fixed to the hull 16 or the like, while transmitting power between the two sun gears 24 and 25. Therefore, braking means 28 is provided so as to restrain the rotation of the carrier 26, and the carrier 26 is also used as a brake disc 29 of a disc brake.

Two pedestals 30 are provided on both sides in the width direction of the hull 16 so as to sandwich the outer peripheral portion of the brake disc 29 from both sides in the front-rear direction of the hull 16.
The stand is installed upright, and the disc pads 31 are mounted inside the U-shaped tip of the gantry 30, respectively, so that the disc brake can be operated by a hydraulic mechanism (not shown) or the like.

Although not shown, the braking means 28 is provided with a controller, which functions as a counter-rotating propeller by engaging a disc brake with a signal from a detector that detects the rotation speed of the main engine 21. Alternatively, the disc brake can be released to switch to single drive of only one propeller.

Power distribution mechanism 23 composed of such a planetary gear mechanism
In addition, the intermediate shaft 33, which is directly connected to the main engine 21 such as a low speed diesel engine and supported by the intermediate bearing 32, is connected to the central sun gear 24, and is also connected to the inner shaft 14 of the counter-rotating shaft 13, so that the stern side is formed. The propeller 11 is directly connected to the main engine 21.

Further, the sun gear 25 at the outer peripheral portion composed of the internal gear and the outer shaft 15 of the counter-rotating shaft 13 are connected, and the propeller on the bow side is connected.
When the rotation of the carrier 26 is restrained by the braking means 28, the driving force of the main engine 21 is distributed from the middle of the inner shaft 14 to the 12 via the sun gear 24, the planetary gear 27, the sun gear 25, and the outer shaft 15. , The direction of rotation is reversed and transmitted.

Next, the contra-rotating propeller device 10 configured as described above is used.
Will be described.

(1) Normal navigation (double inversion drive by braking).

When the front and rear propellers 11 and 12 are reversely driven to perform normal navigation, the disc brake of the braking means 28 is engaged and the carrier 26 of the power distribution mechanism 23 is fixed.

Then, the driving force from the main engine 21 is sent to the power distribution mechanism 23 via the intermediate shaft 33, and transmitted from the central sun gear 24 to the inner shaft 14 to directly drive the stern side propeller 11 and also to the central part. Sun gear 24, planet gears 27, outer sun gear
The inverted driving force is transmitted to the outer shaft 15 by 25, and the bow side propeller 12 is driven.

Therefore, by causing the counter-rotating propeller device 10 to function as the original counter-rotating propeller, the "twist generated in the inner shaft of the counter-rotating shaft and the crankshaft of the main engine" shown in the upper part of FIG. In the range where the rotation speed of the main engine 21 is higher than the engine continuous use prohibited range K and is higher than the rotation speed N, such as the relation between the vibration axial stress and the engine speed, adverse effects such as gear chattering as described above occur. It can improve the propulsion efficiency and economically navigate.

On the other hand, in such a double-reversal drive state, when lowering the rotation speed of the main engine 21 to attempt low-speed navigation at the time of entering and leaving the port, a peak occurs in the vibration torque at a certain low-speed engine rotation speed. This causes adverse effects such as gear chattering.

When the engine speed is low due to such double-reversal drive, as shown in the upper part of FIG.
In the vicinity of the engine speed N1 that causes the engine torque, the stress value F approaches the allowable stress G, and the chattering occurrence area H
Occurs, and the engine speed that produces peak E
A considerable rotation speed range including N1 must be set as the continuous use prohibited range K.

Therefore, the braking means 28 is released and the low speed navigation is performed at the time of entering and leaving the port as follows (2) Low speed navigation (single drive by releasing the braking).

The disc brake of the braking means 28 is released to allow the carrier 26 of the power distribution mechanism 23 to rotate freely.

Then, the planetary gear 27 supported by the carrier 26 becomes 2
Since the sun gears 24 and 25 revolve around the sun while rotating, the drive force from the main engine 21 is not transmitted, and the bow propeller 12 connected to the outer shaft 15 rotates freely as the ship travels. Will be done.

Then, the driving force from the main engine 21 is transmitted to the inner shaft 14 directly connected to the sun gear 24 at the center of the power distribution mechanism 23 via the intermediate shaft 33, and is transmitted to and driven only by the stern side propeller 11.

Accordingly, the mass of the power transmission system is reduced by the amount after the power distribution mechanism 23, and as a result, the natural frequency is increased, and the lower part of FIG. 4 shows “Torsion vibration generated in the inner shaft of the counter-rotating shaft and the crankshaft of the main engine”. As shown in "Relationship between axial stress and engine speed", the peak L of the vibration torque can be moved to the high speed N2 side.

Therefore, the continuous prohibited range when the stern side propeller 11 is used alone is moved to the high rotation side, and the new continuous prohibited range M may be set to the high rotation side. It is possible to operate the ship, and the ship can operate at a very low speed (Dead Slo) without causing problems such as vibration or chattering of gears.
You can move it with w).

Propulsion using only the stern side propeller 11 will reduce the ship speed for the same engine speed compared to when traveling with a counter-rotating propeller, but when such low speed navigation is required, navigation in the port This is a special case such as time or narrow water supply, and it is rather preferable that the boat speed is low, and no problem will occur.

As described above, by changing the mass by engaging and releasing the braking means 28 so that the resonance frequency of the power transmission system and the vibration frequency from the main engine 21 do not match, the continuous use prohibited range K,
It becomes possible to carry out vessel maneuvering without M.

Therefore, in the medium or high speed range where the engine speed is equal to or higher than N which is set in advance, the controller controls the braking means 28 to engage based on the detection signal from the detector, and the engine speed is low when the engine speed is N or lower. In the region, the counter-rotating propeller device 10 can be automatically switched by controlling the controller to release the braking means 28 based on the detection signal from the detector.

Further, according to the counter-rotating propeller device 10, even in the case of emergency navigation when the drive mechanism of the bow side propeller 12 or the propeller itself is damaged, it is possible to simply continue the navigation simply by releasing the braking means 28. You can

Further, in the counter-rotating propeller device 10, since the braking means is used to fix the carrier,
Unlike elastic joints and clutches, it is possible to transmit high horsepower and high torque, and the counter-rotating propeller can be applied to a large ship equipped with a large horsepower main engine.

Although the inner shaft of the counter-rotating shaft is directly connected and the outer shaft is rotated by the planetary gear mechanism in the above-described embodiment, it may be reversed. Further, although the disc brake has been described as an example of the braking means, it may be a drum brake.

[Effects of the Invention] According to the counter-rotating propeller device of the present invention as specifically described above with reference to the embodiment, the power distribution mechanism for reversing drive is constituted by the planetary gear mechanism, and two sun gears are provided. The carrier that supports the planetary gears arranged between them is rotatable, and the rotation of this carrier can be restrained by the braking means. By restraining the carrier, reversal drive is performed and it functions as a double reversing propeller. On the other hand, the carrier can be idled and driven independently by only one propeller, and the mass of the power transmission system can be reduced when the engine speed is low and the resonance point can be lowered to allow navigation in the low engine speed range.

Further, the operation of the contra-rotating propeller can be controlled by fixing and releasing the carrier by the braking means, and power transmission of large horsepower and high torque can be easily performed.

[Brief description of the drawings]

1 to 3 show a counter-rotating propeller device 1 according to the present invention.
FIG. 1 is a longitudinal sectional view in which the braking means is omitted, FIG. 2 is a plan view of the braking means portion, and FIG.
III-III arrow view, FIG. 4 is an explanatory view showing the relationship between the torsional vibration axial stress generated on the inner shaft of the counter-rotating shaft and the crankshaft of the main engine and the engine speed, and FIGS. 5 and 6 are conventional drawings. FIG. 3 is a longitudinal sectional view of the device and an explanatory diagram of a relationship between vibration torque and engine speed. 10: Double reversal propeller device, 11: Stern side propeller, 12: Bow side propeller, 13: Double reversal shaft, 14: Inner shaft, 15: Outer shaft, 16:
Hull, 17: Stern tube bearing, 18: Bearing, 19: Thrust collar, 2
0: Thrust pad, 21: Main machine, 22: Seal device, 23: Power distribution mechanism, 24: Sun gear (external gear), 25: Sun gear (internal gear), 26: Carrier, 27: Planetary gear, 28: Braking Means, 29: brake disc, 30: mount, 31: disc pad, 32: intermediate bearing, 33: intermediate shaft.

Claims (1)

(57) [Claims] 1. In a counter-rotating propeller device for transmitting the driving force of a main engine through a power distribution mechanism to drive two front and rear propellers coaxially in opposite directions, the power distribution mechanism is rotatable with two sun gears. It consists of a planetary gear mechanism equipped with a planetary gear supported by a carrier.The rotation of the planetary gear mechanism is restricted by the carrier of the planetary gear mechanism to reversely transmit the driving force, and the carrier idles to reduce the mass of the vibration system. A contra-rotating propeller device characterized in that a braking means for obtaining the same is provided.