JP2965983B1 - Vertical water jet thruster - Google Patents

Abstract

[PROBLEMS] Conventionally, since a casing and a diffuser have an integral structure, a turning force due to a reaction force of a swirling flow received by the diffuser is transmitted to the casing, thereby increasing the capacity of a casing turning motor. SOLUTION: The casing 10 has a swivelable casing, and the impeller 6 is rotated to push up running water taken from the bottom of the casing 6 to pass through a diffuser 8 so that the inside of the casing 10 is filled with a water flow. In a vertical water jet propulsion device W that discharges a water flow from a certain discharge port, a turning bearing inner ring 5 supported on the hull 1 side and having an impeller shaft 7 inserted therein is provided at an upper portion of a casing 10. And the diffuser 8 is integrally or integrally fixed to the inner ring 5 of the slewing bearing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical water jet propulsion device having a structure in which a diffuser and a casing are separated in order to reduce a turning power required for turning the casing.

[0002]

2. Description of the Related Art A vertical water jet propulsion device is configured so that an intake port and a discharge port are flush with the bottom of a ship, and does not protrude from the bottom of the ship. Due to its shallow depth, it is often used for hull-shaped vessels that cannot secure sufficient propeller depth and cannot be equipped with ordinary tunnel-type thrusters. Prior art disclosing this type of vertical water jet propulsion includes JP-A-6-2.
No. 78692, JP-A-6-286693, JP-A-7-52882, JP-A-8-58689, and the like. In such a vertical water jet propulsion machine,
Since the casing body including the discharge port can be turned in any direction of 360 °, thrust can be generated in any direction, and the maneuverability of the boat can be improved. FIG. 3 is a longitudinal sectional view of a vertical water jet propulsion device described in the above-mentioned Japanese Patent Application Laid-Open No. 7-52882. FIG. 4 is a plan view at the diffuser position.

[0003] As shown in the figure, the discharge flow sucked from the water intake port 53 at the center of the bottom surface 52 a of the casing 52 by the rotation of the impeller 51 and flowing out above the impeller 51 is accompanied by a swirling flow due to the rotation of the impeller 51. The diffuser 54 downstream of the impeller 51 converts the swirling flow into the vane 5.
5 has a function of bending, and has a function of changing the direction at the vane outlet so as to flow in the radial direction. If the discharge flow flows into the casing 52 with the swirl flow remaining, the swirl energy also causes a friction loss with the casing wall surface, resulting in a large energy loss. Diffuser 5
Reference numeral 4 also has a role of gradually converting the kinetic energy of the water flow into pressure energy by increasing the cross-sectional area of the flow path, thereby increasing the generated thrust. Therefore, the diffuser 54 having the vane 55 is one of essential components for a vertical water jet propulsion device.

In each of the above-described conventional vertical water jet propulsion machines, the diffuser 54 is provided with a casing 52.
And the casing 52 and the diffuser 5 are driven by the rotation motor 56.
4 is a structure type that turns together.

[0005]

As shown in FIG. 4, the diffuser 54 generates a turning force (turning moment) Y in the direction of the arrow due to the reaction force F received from the water flow in the vane 55, but the force is large. For this reason, the casing 52
The effect on the capacity of the swing motor for turning 360 ° in any direction is very large.

That is, the swing motor 56 controls the casing 5
When the diffuser 54 turns in the same direction as the direction in which the diffuser 54 receives the turning force (turning moment) Y in the direction of the arrow in FIG. 4, the casing 52 itself turns freely, and the turning motor 56 turns. Turns with a small amount of power (conversely, it is necessary to stop the rotation with the turning motor). On the other hand, when turning in the opposite direction, the "moment due to frictional resistance and the total inertial force of the casing"
+ Comparing those values, a large force is needed to overcome the sum of the turning moment due to a water flow that is incomparably large, and the capacity of the turning motor needs to be selected by the amount of power. However, its power consumption is an important issue, especially for workboats with low power generation capacity.
It is desirable that the abilities are as small as possible from the viewpoint of both initial and running costs. In addition, since the swing motor must be arranged in a limited space, it is required to reduce the capacity of the swing motor to make the swing motor itself as small as possible.

In the above-mentioned conventional example, the impeller shaft seal 57 is attached to the revolving casing 52 as shown in FIG. Therefore, the turning direction is the impeller 51.
In the case of the reverse rotation with respect to the rotation direction, the relative peripheral speed of the seal contact portion is a value obtained by adding the turning speed and the impeller rotation speed, so that the use conditions of the seal are severe and the seal life must be shortened.

[0008]

In order to solve the above-mentioned problems, a vertical water jet propulsion device according to the present invention has a casing which can be turned by a turning motor, rotates an impeller, and moves the impeller from the bottom of the casing. In a vertical water jet propulsion device that pushes up the flowing water to the upper part, passes through the diffuser, fills the inside of the casing with water, and discharges the water flow from the discharge port at the bottom of the casing, it is supported on the hull side and the impeller shaft is inserted. The slewing bearing inner ring is provided on the upper portion of a casing, and the casing is supported on the slewing bearing inner ring via a slewing ring bearing, while the diffuser is integrally or integrally fixed to the slewing bearing inner ring.

As a result, the inner ring of the slewing bearing forms a stationary portion supported on the hull side, and the diffuser and the casing are separated and separated. The turning moment by changing the direction of the swirling flow in the diffuser does not act on the casing, and the diffuser is stationary even when the casing is in the turning state. Therefore, the swing motor required to swing the casing itself requires a small amount of power.

In this case, a simple structure is provided in which the lower end of a cylindrical turning bearing inner ring extending downward in connection with the gear box is located in the casing, and the diffuser is integrally attached to the lower end of the turning bearing inner ring. Become.

Further, an impeller shaft seal is provided between the stationary diffuser portion or the inner ring portion of the slewing bearing and the rotating impeller shaft to shut off the seawater chamber and the lubricating oil chamber, thereby preventing leakage and intrusion of each other. I can do it.

A turning seal is provided between the stationary diffuser portion or the inner ring portion of the turning bearing and the turning casing portion to shut off the seawater portion and the lubricating oil chamber so as to prevent mutual leakage and intrusion. Can be.

Further, if the joint surface of the diffuser and the inner ring of the swing bearing to which the diffuser is attached is formed in a tapered shape such that the joint surfaces are pressed against each other by the swirling force due to the reaction force of the water flow received by the diffuser, , And the diffuser mounting bolt can be reduced in size or number.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic longitudinal sectional view of a water jet propulsion device W according to the present invention.

The water jet propulsion machine W is mounted on a hull 1 and has an installation flange 4 in which a gear box 3 having a built-in power transmission mechanism 2 is installed upright in the center, and an installation flange 4.
A slewing bearing inner ring 5 extending downwardly at the center, an impeller shaft 7 having the slewing bearing inner ring 5 penetrated therethrough and having an impeller 6 at a lower end, and a slewing bearing inner ring 5 located downstream of the impeller 6 are attached. It comprises a diffuser 8, a casing 10, and the like, which are supported on a swing bearing inner ring 5 so as to be swingable by a swing motor 9.

The mounting flange 4 is provided on the opening 1c of the hull 1 and is fixed on the inner bottom plate 1a of the hull 1.
The gear box 3 erected at the center of the installation flange 4
A drive shaft 11 extending from a prime mover (not shown) is inserted and supported. A pinion gear 2a is provided at the tip, and a wheel gear 2b that meshes with this and forms the power transmission mechanism 2 is provided. Below this wheel gear 2b, an impeller shaft 7 is inserted and suspended inside a cylindrical turning bearing inner ring 5, and is supported by upper and lower bearings 7a.

The slewing bearing inner ring 5 is connected to the gear box 3 and extends downward in a cylindrical shape. A diffuser 8 is attached to a flange portion 5a at a lower end of the slewing bearing 5 by a large number of attachment bolts 8b and slides on the impeller shaft 7. An impeller shaft seal 12 is attached. The slewing bearing inner ring 5 is attached to or connected to the installation flange 4 fixed to the hull 1 to form a stationary part, and the diffuser 8 attached to be connected to the slewing bearing inner ring 5 does not rotate. Fixed part).

As described above, by providing the impeller shaft seal 12 between the stationary diffuser 8 or the rotating bearing inner ring 5 and the rotating impeller shaft 7, the seawater portion 1 is provided.
2a and the lubricating oil chamber 12b are shut off to prevent leakage and intrusion of each other.

On the other hand, the cylindrical casing 10 has the opening 1
The turning ring 13 is provided upright at the center thereof, concentrically with the turning bearing inner ring 5. The slewing wheel 13 is engaged with and supported by the slewing bearing inner ring 5 via a slewing bearing 14, and is separated from the diffuser 8 so as to be able to turn independently. That is, the diffuser 8 of the stationary part and the casing 10 of the turning movable part are connected to the turning seal 15.
The two parts are separated and separate from each other only by engaging and sliding contact with each other.

In the same manner as described above, the seawater portion 12a and the lubricating oil chamber 12b are shut off by the turning seal 15 provided between the stationary diffuser 8 or the turning bearing inner ring 5 and the turning casing 10 portion. To prevent leakage and intrusion of each other. Also, a seal 4a is provided between the casing 10 and the installation flange 4 to shut off the seawater portion and the lubricating oil chamber.

An engaging gear 13a is formed on the turning wheel 13 of the casing 10 and meshes with a gear 9b at the lower end of a turning shaft 9a of a turning motor 9 disposed on the installation flange 4 and driven by the turning motor 9. The casing 10 turns independently.

A water intake 16 is formed at the center of the bottom surface 10 a of the casing 10, and an inner wall (impeller liner) 10 b rises so as to surround the impeller 6. The diffuser 8 is provided separately from the inner wall 10b (that is, the casing 10) so as to be continuous with the upper end of the inner wall 10b. Diffuser 8 has impeller 6
A passage is formed for the water flow that has been pushed upward from and has flowed out, and a radial vane 8a for guiding the passage is provided.
As described above, the water flow coming out of the impeller 6 becomes a swirling flow and acts on the vanes 8a. And does not affect the turning of the casing 10. Therefore, the turning motor 9 only needs to have a small amount of force necessary to turn the casing 10 itself.

The water flowing out of the diffuser 8 enters the interior (pressure chamber) 17 of the casing 10 communicating with the diffuser 8, and the water in the pressure chamber 17
The ejection thrust is generated from the discharge port 18 having the guide vanes 18a formed at the position a. By rotating the casing 10, the position of the discharge port 18 can be freely changed by 360 °.

FIGS. 2 (a) and 2 (b) show an example of a structure in which the function of fixing the diffuser to the inner ring of the slewing bearing is enhanced by utilizing the slewing force generated as a reaction force of the vane in the diffuser.

That is, at the joint surface 18 between the annular member 8c protruding from the center of the diffuser 8 and the flange 5a at the lower end of the swivel bearing inner ring 5 to which the annular member 8c is attached, the turning force Y due to the reaction force of the water flow received by the diffuser 8 is obtained. By forming the taper 18a so that the joining surfaces 18 are pressed against each other, a self-locking method is achieved, and the mounting bolts 8b (FIG. 1) of the diffuser 8 can be reduced in size or number.

[0027]

The present invention is embodied in the form described above and has the following effects.

Since the diffuser is separate from the casing, no turning force acts on the casing. Therefore, the amount of power of the swing motor only depends on the frictional resistance and the moment due to the total inertial force of the casing, and the value is a very small and negligible level. Therefore, the power of the swing motor can be very small, about 1/5 of the conventional one, and the required power generation capacity can be very small.

Since the impeller shaft seal is attached to the stationary part, the peripheral speed of the seal contact part is only the rotation speed of the impeller, and the seal can have a structure that is reasonable in terms of life.

Since the swirling seal is provided between the stationary portion and the rotating casing portion, the seawater portion and the lubricating oil chamber can be shut off, thereby preventing leakage and intrusion of each other.

Since the joint surface of the diffuser is tapered, that is, the diffuser is shaped so as to be of a self-locking type, no turning force acts on the diffuser mounting bolts or the fixing pins (not shown). For this reason, mounting and fixing can be performed with a small size or a small number, and a reduction in size and a reduction in weight can be achieved.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a water jet propulsion device W according to the present invention.

FIGS. 2 (a) and 2 (b) are a schematic main part view and a perspective view of a structural example in which a function of fixing a diffuser to an inner ring of a slewing bearing using a slewing force generated as a reaction force of a vane is enhanced. .

FIG. 3 is a longitudinal sectional view of a conventional vertical water jet propulsion device.

FIG. 4 is a plan view at the diffuser position.

[Explanation of symbols]

 W ... vertical water jet propulsion machine 1 ... hull 2 ... power transmission mechanism 3 ... gear box 4 ... installation flange 5 ... swing bearing inner ring 6 ... impeller 7 ... impeller shaft 8 ... diffuser 8a ... vane 9 ... swing motor 10 ... casing 12 ... impeller shaft seal 13 ... rotating ring 14 ... rotating ring bearing 15 ... rotating seal 16 ... water intake 17 ... pressure chamber 18 ... discharge port

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B63H 11/08 B63H 11/113

Claims (5)

(57) [Claims] 1. A casing having a casing rotatable by a pivoting motor, wherein the impeller rotates to push up flowing water taken from a bottom face of the casing to an upper portion thereof, pass through a diffuser and fill the inside of the casing with a water flow, and the casing has a bottom face. In a vertical water jet propulsion device that discharges water flow from a discharge port, a slewing bearing inner ring supported on the hull side and having an impeller shaft inserted therein is provided at the upper center of the casing, and the casing is connected to the slewing bearing inner ring via a slewing ring bearing. A vertical water jet propulsion device characterized in that the diffuser is integrally or integrally fixed to the inner ring of the slewing bearing while being supported. 2. A lower end portion of a cylindrical turning bearing inner ring extending downward in connection with a gear box is located in a casing, and a diffuser is integrally attached to the lower end portion of the turning bearing inner ring. The vertical water jet propulsion device according to 1. 3. An impeller shaft seal is provided between a stationary diffuser portion or a rotating bearing inner ring portion and a rotating impeller shaft to shut off a seawater portion and a lubricating oil chamber. The vertical water jet propulsion device as described. 4. A seawater part and a lubricating oil chamber are shut off by providing a turning seal between a stationary diffuser portion or a turning bearing inner ring portion and a turning casing portion. 2. The vertical water jet propulsion device according to claim 1. 5. The joint surface of the diffuser and the inner ring of the swivel bearing to which the diffuser is attached is formed in a tapered shape such that the joint surfaces are pressed against each other by a swirling force due to the reaction force of the water flow received by the diffuser. The vertical water jet propulsion device according to any one of claims 1 to 4.