JPH0347238B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a simple water jet propulsion device.
More specifically, the present invention relates to a simple water jet propulsion device installed under the bottom of a small boat.

[Prior art] As a conventional water jet propulsion device,
There is one described in Publication No. 1562.

In this device, an impeller 105 is arranged in an impeller duct 101 as shown in FIG.
is formed. The rudder plate 114 is the 11th
As shown in the figure, both ends are completely fitted into the wheelhouse 100. The shape of the steering plate 114 is such that a protrusion 114g is formed on one side edge, and a step 114a is formed on the lower edge.

[Problem to be solved by the invention]

However, the conventional device has the following problems.

It is very difficult to go backwards.

That is, in the conventional device, the reverse operation is performed by turning the step 114a of the steering plate 114 forward and rotating the impeller as shown in FIGS. 12a and 12b. erupts from.
However, even if this jet stream hits the steering plate 114 and is decelerated, it is immediately discharged from the opening 121 in front of it, so the injection force is weak and a sufficient backward force cannot be generated. Therefore, it is also not possible to turn the ship during an astern maneuver.

Neutral stopping is extremely difficult.

In the conventional device, the neutral stop operation is performed in the 13th
As shown in Figures a to 13b, the step 114a of the rudder plate 114 is directed rearward to direct the jet flow toward the rudder plate 1.
This is done by squirting it directly downwards after applying it to 14.

However, since jetting directly downwards does not have the power to actively restrict the ship's forward and backward movement, it can only be brought to a partial stop, and a complete stop is difficult.
Particularly when the impeller is rotating at high speed, turbulence occurs due to the impeller's twisting and turning, which usually causes the ship to operate unstablely.

Thrust loss is large.

The steering plate 114 of the conventional device has protrusions 114g formed at the side ends of the steering plate 114 in order to maintain hydrostatic balance and control its movement in all directions easily. Such protrusions naturally create resistance, resulting in loss of thrust.

If the debris is clogged, the rudder will not move properly.

In the conventional device, since both ends of the steering plate 114 enter the steering room (so-called double-sided contact), the steering plate 114 may become stuck if dirt or sand a gets caught in it, as shown in FIG. .

When the rudder plate 114 is oriented diagonally, the jet flow wraps around the rear surface of the rudder plate 114, which reduces the operational effectiveness of the rudder.

As described above, the conventional devices have caused various problems in terms of ship operation.

In view of the above circumstances, the present invention has been developed to provide a simple system that enables powerful reverse operation, stable neutral stopping, little loss of thrust, and can be easily cleared even if the rudder becomes clogged with debris. The object of the present invention is to provide a type water jet propulsion device.

[Means to solve the problem]

The simple water jet propulsion device of the present invention has an impeller and a guide vane arranged in an impeller duct, a main nozzle formed behind the guide vane, a wheelhouse provided behind the main nozzle, and a support at the exit of the wheelhouse. This is a water jet propulsion device in which a rudder plate is rotatably mounted on a shaft, and the side wall in the rudder room has an opposing wall shaped to follow the rotation locus of the side edge of the rudder plate from the tip of the main nozzle to the rudder room. At the same time, the cross section of the wheelhouse is formed into a rectangular cylindrical shape, and the width of the steering plate is made larger than the inner width of the wheelhouse, so that one side edge rotates within the wheelhouse while the other side edge rotates inside the wheelhouse. The side edges protrude from the rudder house, and the lower edge of the rudder plate is formed with an L-shaped shielding plate that protrudes laterally. The neutral relief port is formed at a position spaced apart from the plate, and is formed so that it is formed between the rudder plate and the steering room when the L-shaped shielding plate of the rudder plate is directed rearward. Features.

[Function] Regarding backward operation In the present invention, if the exit of the steering room is closed with the rudder plate and the L-shaped shielding plate is directed forward, the jet stream accelerated by the impeller and ejected from the main nozzle will collide with the rudder plate and Since the reverse injection port is located away from the steering plate, the inside of the rear duct (the cavity between the main nozzle outlet and the steering room) is in a pressure injection state. Since the pressure jet is ejected from the reverse injection port, a strong propulsive force is obtained.
In other words, since the reverse injection port is located far from the rudder plate, it functions like a type of nozzle.

Also, if the rudder plate is turned slightly diagonally, jets will be ejected from the gap between the rudder plate and the steering room (in this case, most of the jets will be ejected from the reverse injection port), and the reaction will cause It is possible to turn backwards.
That is, the ship can be turned left and right while moving backward.

About neutral stop operation Next, when the direction of the steering plate is changed by 180 degrees and the L-shaped shielding plate is facing rearward, a neutral relief opening is created between the steering plate and the wheelhouse. A jet flow is ejected into this neutral relief port in the opposite direction to the reverse injection port, so the jet flow from the reverse injection port and the jet flow from the neutral relief port exert thrust in opposite directions, and are active. Keep the ship in a neutral state. Therefore, the neutral ship stopping operation according to the present invention works stably, and the ship will not move unstablely even if a small amount of external force is applied.

Regarding Operability and Thrust Loss The rudder plate according to the present invention has a longer width by making the width of the rudder plate larger than the inside of the steering room. For this reason, the rudder plate has a strong tendency to return straight along the jet flow, so it is easy to hold the rudder plate immediately when traveling straight, and when turning, the jet force is applied to the rudder plate, but to a certain extent. When the ship turns, forces act on the left and right sides of the rudder around the support shaft and are balanced, so the operating force is small. Therefore, the steering operation is easy.

As described above, in the present invention, the operability is improved by lengthening the steering plate, so there is no need to provide a protrusion on the steering plate as in the conventional device. Therefore, the steering plate of the present invention may be a straight plate and does not have any protrusions, resulting in less resistance and less thrust loss.

Measures against clogging with debris The steering plate according to the present invention has a single-sided structure in which one side edge enters the steering room and the other side edge protrudes from the steering room. Therefore, even if dirt or sand gets stuck between the rudder board and the wheelhouse, it is easier to disengage and restore the rudder's movement than if it were stuck at both ends. .

Regarding the operating effect of the rudder In the present invention, since no gap is created between the rudder plate and the rudder plate due to the opposing wall, the jet flow does not flow turbulently on the back surface of the rudder plate. Therefore, the operating effect of the rudder is high.

〔Example〕

Next, one embodiment of the present invention will be described based on the drawings.

In FIGS. 1 and 2, reference numeral 4 denotes an impeller duct which is bolted to the lower surface of the ship's bottom 2 by means of duct mounting brackets 8 and 18. The impeller 5 is fixed to the shaft 3 through the stub tube 1 and arranged in the impeller duct 4. In addition, a guide vane 7 is fixed inside the impeller duct 4 behind the impeller 5, and a board bearing 6 is attached to the guide vane 7.
A rear end shaft 22 of the impeller 5 is supported on the shaft 22 .

A main nozzle 9 is formed at the rear end of the impeller duct 4. Reference numeral 21 indicates a ventilate portion of the main nozzle 9.

A steering room 20 is formed behind the main nozzle 9. The inside of this steering room 20 has a rectangular tube-like cross section. Continuing with the ventilate portion 21 of the main nozzle 9, an opposing wall 2 is provided within the wheelhouse 20.
4 is formed. This opposing wall 24 is connected to the steering room 2
Since jet flow is prevented from intruding behind the operating surface of the rudder plate 12 within the range of 0, the operating effect of the rudder is not reduced. That is, no matter where the steering plate 12 is located, the jet flow can be received by the operating surface and the steering action can be performed effectively.

The steering plate 12 is rotatably attached to the exit-side open end of the steering room 20 by a support shaft. That is, the rudder shaft 11 is inserted into the upper edge of the rudder plate 12 and fixed with a pin. Further, a lower shaft 14 is fixed to the lower edge of the rudder plate 12. This lower shaft 14 is rotatably supported by a bracket 15 fixed to the lower surface of the steering room 20.

The lower edge of the steering plate 12 is bent as shown in FIG. 3 to form an L-shaped shielding plate 13. The rudder plate 12 is rotated by a bow handle (not shown) connected to the sheave 10 fixed to the rudder shaft 11 by a rope.

A reverse injection port 16 for backward movement is formed on the lower surface of the back side of the main nozzle 9. This reverse injection port 16
The position is not directly below the steering plate 12 but at a position spaced forward, so that a rear duct is formed between the ventilate portion 21 and the steering plate 12.

Further, as shown in FIG. 4, the rear lower end of the steering room 20 is formed so that an opening is formed when the L-shaped shielding plate 13 of the steering plate 12 is directed rearward. This opening is called a neutral escape port 17.

Next, the operation of the above embodiment will be explained based on FIG. 2.

The water accelerated by the impeller 5 passes through the guide vanes 7 and is squeezed by the ventilate section 21 of the main nozzle 9 to become a jet stream. Then, it is injected into the steering room 20.

When the rudder plate 12 is in position a (Figs. 8a and 8b)
(see figure), the jet flow hits the rudder plate 12, is reversed, and is injected from the reverse injection port 16, so the ship moves backward. In this case, the steering plate 12 and the reverse injection port 16 are spaced apart, and the inside of the rear duct between the ventilate portion 21 and the steering plate 12 is in a pressure injection state, so that the injection force becomes strong. Therefore, a much stronger backward force can be obtained compared to the conventional example.

When the rudder plate 12 is in position b, most of the jet flow is injected from the reverse injection port 16, while a small amount of jet flow is ejected to the left from the gap between the rudder plate 12 and the rear end of the steering room 20. While moving astern, the bow swings to the left and turns. Similarly, when the rudder plate 12 is set to the f position, the boat turns with the bow to the right while moving backward. In this way, the present invention allows a backward turning operation.

When the rudder plate 12 is in the g position (Figs. 9a and 9b)
After the jet flow collides with the rudder plate 12, it is ejected from both the reverse injection port 16 and the neutral relief port 17. In this case, the directions of the jet from the reverse injection port 16 and the jet from the neutral relief port 17 are diametrically opposite, and their reaction is canceled out to each other to actively bring the ship to a neutral stop. Therefore, even if some external force is applied, the ship will not move unstablely and can be stopped in a stable state. Note that when stopping in neutral, the engine is used at low speed.

When the rudder plate 12 is in the c position, the ship moves forward while swinging its bow to the left and turns, and when it is in the e position, it moves forward while turning its bow to the right. Moreover, in the case of position d, the ship moves straight.

During such maneuvering, since the rudder plate 12 of the present invention has a long width, the rudder plate tends to return straight along the jet flow, and it is easy to hold the rudder plate 12 straight when proceeding straight. . Further, when making a turn, a jetting force is applied to the rudder plate 12, but once the ship turns to a certain extent, the forces act on the right and left sides of the rudder plate 12 around the spindle and are balanced, so the operating force is small. Therefore, the steering operation is easy.

As described above, since the operability is improved by lengthening the steering plate 12, there is no need to provide a protrusion on the steering plate as in the conventional device. Therefore, as in this embodiment, the rudder plate 12 may be a straight plate without any protrusions, resulting in less resistance and less thrust loss.

The steering plate 12 of this embodiment has one side edge connected to the steering room 20.
It has a one-sided structure in which the other side edge protrudes from the wheelhouse 20. Therefore, even if dirt or sand gets stuck between the rudder plate 12 and the wheelhouse 20, it is easier to disengage the mesh and restore the rudder's movement than if it were stuck at both ends. I can do it.

Next, another embodiment will be described.

FIG. 5 is a longitudinal sectional view of the second embodiment. In the first embodiment, the struts 19 are not attached, but in this embodiment, the struts 19 are provided in the tunnel-shaped bottom of the ship. Therefore, even if the rear end shaft 22 of the impeller 5 is not provided, the impeller 5 is supported by the bearing of the stand tube 1 and the bearing of the strut 19.
Even when the impeller 1 is rotated by the engine, it does not shake.

When the bearing 6 in the duct 4 is provided and fitted to the shaft 3, the attachment of the duct 4 can be maintained even if the duct mounting bracket 8 is removed. This embodiment makes it easier to replace the bearing and clean the inside of the casing. FIG. 6 shows that the attachment of the impeller duct 4 in the second embodiment shown in FIG. 5 can be maintained. This embodiment makes it easier to replace the bearing and clean the inside of the casing.

FIG. 6 shows the main body of the impeller duct 4 in the second embodiment shown in FIG. 5, and shows a state where it is separated from the driving portion of the shaft 3.

FIG. 7 is a schematic rear view of the device according to the present invention, in which the impeller duct 4 is cylindrical, and the wheelhouse 20 is
has a rectangular cylindrical shape. These are not separate things,
It has a one-piece structure, with a rudder plate 12 mounted inside a rectangular cylindrical tube to perform rudder action, reverse movement, and neutral stopping action.

〔Effect of the invention〕

According to the present invention, a simple water jet propulsion device is capable of providing a strong reverse force and stable neutral stop operation, has good operability, has little loss of thrust, and can easily eliminate dust clogging. can be provided.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention, FIG. 2 is a plan view of the main parts of the present invention and an explanatory diagram of the operation of the rudder plate,
Fig. 3 is a perspective view of the main part of the present invention, Fig. 4 is a longitudinal sectional view of the main part and an explanatory diagram of the effect of jet flow, and Figs. 5 and 6 are longitudinal sectional views showing a second embodiment of the invention. , FIG. 7 is a rear view of the present invention, FIGS. 8a and 8b are illustrations of the reverse operation in the first embodiment of the invention, and FIGS. 9a and 9b are illustrations of the neutral stop operation of the same embodiment. Fig. 10 is a sectional view of a conventional water jet propulsion device, Fig. 11 is a plan view of a conventional rudder plate, Figs. 12a and 12b are explanatory diagrams of reverse operation of the conventional example, and Fig. 13a is FIG. 13b is an explanatory diagram of a conventional neutral stop operation. (Drawing codes) 4: Impeller duct, 5: Impeller, 7: Guide vane, 9: Main nozzle, 12:
Rudder plate, 13: L-shaped shielding plate, 16: Reverse injection port, 1
7: Neutral escape port, 20: Wheelhouse, 24: Opposing wall.

Claims (1)

[Scope of Claims] 1. An impeller and guide vanes are arranged in an impeller duct, a main nozzle is formed behind the guide vanes, a steering room is provided behind the main nozzle, and a steering plate is connected to the exit of the steering room by a support shaft. The water jet propulsion device is rotatably attached to a water jet propulsion device, in which an opposing wall is formed on the side wall of the steering room from the tip of the main nozzle to the steering room, and has a shape that follows the rotation locus of the side edge of the steering plate. , the cross section of the wheelhouse is formed into a rectangular tube shape, and the width of the steering plate is made larger than the inner width of the wheelhouse, so that one side edge rotates within the wheelhouse while the other side edge rotates inside the wheelhouse. An L-shaped shielding plate is formed on the lower edge of the rudder plate, which protrudes from the chamber, and protrudes laterally. A simple type characterized in that the neutral relief port is formed between the rudder plate and the steering room with the L-shaped shielding plate of the rudder plate facing rearward. Water jet propulsion device.