JP2592729Y2 - Variable intake for water jet pump - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water jet pump intake, and more particularly, to a water jet pump which can take a large amount of water at low speed without increasing the hull resistance at high speed. It relates to a variable intake.

[0002]

2. Description of the Related Art In recent years, water jet pumps (hereinafter referred to as "water jet pumps") have been developed.
It is simply called WJ pump. ) Is frequently used as a propulsion device for high-speed ships.

[0003] As a hull type employing this WJ pump,
For example, as shown in the schematic side view of FIG. 4 (a) and the CC view of FIG. 4 (b), a hull 1 and a submerged body 2 to be a floating body are connected by struts 4, and both sides of the submerged body 4 There is a hydrofoil ship J provided with a hydrofoil 3.

[0004] The hydrofoil J is provided with an intake port 5 at the bottom of the submerged body 2, and water taken from the intake port 5 A passes through an intake pipe 6 through a main engine 7. It is pressurized by the driven WJ pump 8 and jetted to the rear of the hull.

In such a hydrofoil ship J, the hull 1 travels in a boat-running state in which the hull 1 is slightly submerged in the water at low speed, and the hull 1 rises from the water surface W at high speed due to the buoyancy of the submerged body 2 and the lift of the hydrofoil 3. The wing running in the state shown in the drawing is brought up.

The water intake 5A shown in FIGS. 4 (a) and 4 (b) is a flush type water intake system.
Are provided without protruding from the bottom of the ship, and water taken from the water intake port 5A is jetted by the WJ pump 8 to obtain thrust (conventional example 1).

On the other hand, a schematic side view of FIG.
The intake port 5B shown in the arrow D view shows a pod-type intake system, in which an intake pod 51 is provided from the bottom of the submerged body 2 at the bottom.
The WJ pump 8 jets water taken from an intake port 5B on the front face of an intake pod 51 projecting from the bottom of the ship to obtain thrust (conventional example 2).

[0008] As a prior art of this kind, Japanese Utility Model Laid-Open No.
There is -112199 publication, and the device described in this publication is
The suction port provided in the introduction duct (water intake port) is configured to be able to advance and retreat with respect to the introduction duct (conventional example 3).

[0009]

By the way, in the case of a ship in which the hull 1 separates from the water, such as a hydrofoil ship J shown in the above-mentioned conventional examples 1 and 2, the head from the water surface W to the position of the WJ pump 8 is increased. And the WJ pump 8 cannot be driven efficiently unless there is sufficient water pressure to accommodate the suction head.

In other words, the prior art 1 does not increase the hull resistance at the water intake port 5A because there is no projection from the bottom of the boat, but there is no problem at high speed because the water intake efficiency is poor in the conventional example 1. However, at low speeds, the suction pressure was low, and it was extremely difficult to obtain sufficient water to drive the WJ pump 8. For this reason, it is difficult to apply the flush type to a ship such as a hydrofoil ship having an intake pipe 6 having a large suction resistance.

On the other hand, in the above-mentioned conventional example 2, since water is taken from the water intake port 5B on the front surface of the water intake pod 51 projecting from the bottom of the ship, the water intake efficiency at low speed is very good. It became a big obstacle in the hull resistance,
This has increased the hull resistance.

Although the increase in the hull resistance depends on the hull shape, studies by the inventor have shown the relationship shown in FIG. 6, and it has been found that the pod-type hull resistance is about 110% of that of the flash type. In other words, in order to make the boat run at the same boat speed, the output of the main engine of the pod type needs to be 10% larger than that of the flash type.

By the way, the generated thrust can be increased by increasing the rotation speed of the pump. FIG. 8 is a graph showing the relationship between the pump speed N and the generated thrust TH of the pump. As shown in this graph, the generated thrust is proportional to the square of the pump speed. FIG. 7 shows the relationship between the intake pipe pressure and the pump allowable rotation speed. As shown in this graph, if the pump allowable rotation speed is increased by a predetermined rotation speed or more while the pressure of the intake pipe 6 is low, cavitation hazard may occur. If the pressure is lower than the predetermined pressure, the pump rotation speed cannot be increased. Conversely, the higher the pressure in the water intake pipe, the safer the cavitation of the pump, the higher the allowable rotation of the pump and the greater the thrust generated.

That is, from the relationship between FIG. 7 and FIG. 8, it can be seen that the higher the pressure of the water intake line, the higher the rotation speed of the pump, and consequently the greater the thrust generated by the pump. In other words, the higher the water intake efficiency, the higher the speed of the ship's hull in a shorter period of time, and the more excellent the operation of acceleration.

However, as described above, in the first conventional example, it is difficult to increase the pressure of the intake line 6, and in order to increase the pressure of the intake line 6, the intake pod 51 must be However, in this case, the hull resistance must be increased.

In the prior art 3, the suction port is in a retracted state when starting from a stop, and the water is sucked by moving forward when traveling at high speed. In the case of this invention, the purpose of improving the acceleration performance of the hull is improved. Not applicable to other ships. In addition, in the present invention, since the suction port can be moved only in the same direction as the inclination angle of the introduction duct, when the suction port is advanced, suction is performed with a water intake area smaller than the opening area at the time of storage, and water intake efficiency is poor.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a variable water intake of a water jet pump capable of optimizing water intake efficiency according to a ship speed without increasing the hull resistance.

[0018]

In order to achieve the above object, a variable intake for a water jet pump according to the present invention uses a strut to connect a hull and a submerged body to be a floating body.
The submerged body of the connected hydrofoil has an intake port on the bottom surface, and the water sucked from the intake port is driven by the main engine via a water pipe .
A drive shaft is provided at the back of the water intake pump, which is pressurized by a water jet pump and jetted rearward of the hull, and a variable lip is swingably provided on the drive shaft. , Submerged body bottom on both sides of the variable lip
The height gradually increases with a gentle slope from the front end of the surface intake
Almost maximum height at the tip of the variable lip on the side of the intake pipe
And the height gradually increases from the maximum height position with a gentle inclination.
Immersion at a position behind the drive shaft of the variable lip
It is characterized by providing a side fence that is continuous to the body bottom .

Further , in this configuration, in the above-mentioned intake pipe,
Lower bend of the rear wall connected to the water jet pump
Provide a pressure detector for detecting the pressure in the intake pipe in the section,
Optimum variable pressure according to the suction pressure detected by the pressure detector
Adjust the lip swing angle and adjust the position of the variable lip
The water jet pump for optimum
It may be operated at a water intake efficiency.

[0020]

According to the above construction, at the time of low speed navigation, the variable lip is swung by the drive shaft provided at the rear of the water intake so as to protrude from the bottom of the boat, so that water is easily sucked from the water intake and even at low speed. Water intake with good water intake efficiency becomes possible.
At this time, water leakage from the lip side due to the side fence
And ensure that the suction flow rate is in accordance with the amount of protrusion of the lip.
Can be.

Further, at the time of rated output during high-speed navigation or the like, the variable lip is swung by the drive shaft and stored in the bottom of the ship, so that the hull resistance does not increase.

Further, the variable lip swing angle is adjusted in accordance with the suction pressure detected by the pressure detector provided on the rear wall surface of the water intake pipe, and the position of the variable lip is fed back. Can always be operated at an optimal water intake efficiency.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a drawing showing a hydrofoil provided with a variable intake according to the present invention. FIG. 1 (a) is a schematic side view, FIG. 1 (b) is a view along AA, and FIG. 2 is an enlarged view showing the variable intake. FIG. 3 is a sectional view of FIG.
FIG. In the following embodiment, an example will be described in which the present invention is applied to an intake port of a hydrofoil boat J having a large head from the water surface W as in the above-described related art. Note that the same components as those of the above-described conventional example are denoted by the same reference numerals and described.

As shown, the hydrofoil J has a hull 1, a submerged body 2, and hydrofoils 3 provided on both sides of the submerged body 2. They are connected by struts 4. An intake port 5 is provided at the bottom of the ship below the submerged body 2. Water taken from the intake port 5 passes through an intake pipe 6 and is pressurized by a WJ pump 8 driven by a main engine 7. It is squirted to the rear of the hull.

As shown in FIG. 2, the water intake 5 is continuous with the water intake pipe 6 while drawing a gentle curved surface from the bottom of the submerged body 2 so as to easily take in water flowing from the bow side to the stern side. It is formed by being surrounded by a side fence 18 having such an inclination.

A variable lip 9 is supported at the rear of the water intake port 5 on the hull side by a drive shaft 10.
0 allows the variable lip 9 to swing. An operating lever 11 is provided at one end of the drive shaft 10,
An end of the operating lever 11 is connected to an end of a piston 13 of a hydraulic cylinder 12, which is an actuator. The rear end of the hydraulic cylinder 12 is connected to the hull side, and when pressure oil is supplied through a hydraulic pipe 14, the piston 13 moves forward and backward to swing the variable lip 9 via the operating lever 11. An angle detector 15 is provided at the other end of the drive shaft 10 so as to detect the swing angle of the drive shaft 10. This angle detector 15 may detect other means, for example, the position of the piston 13. A bearing 16 is provided on the hull-side support portion of the drive shaft 10, and a water-tight structure is formed by providing a seal member 17 for sealing between the bearing 16 and the hull 1.

Side fences 18 are provided on both sides of the water intake port 5 provided on the bottom of the submerged body 2, and a variable lip 9 is provided inside the side fence 18 so as to be swingable. I have.

Further, as shown in FIG. 2, the water intake pipe 6 is provided with a pressure detector 19 at one place. The pressure detector 19 may be provided at a plurality of locations.

An operation state of the variable lip 9 of the variable intake H of the present invention having the above-described structure will be described below. First, the operating lever 11 is rotated by moving the piston 13 of the hydraulic cylinder 12 provided on the hull side in accordance with the boat speed, and the rotation of the operating lever 11 causes the drive shaft 10 to rotate. The integrated variable lip 9 is swung.

The swing of the variable lip 9 depends on the suction pressure measured by a pressure detector 19 provided near the inlet of the water intake pipe 6,
Alternatively, the pressure sensor 19 and the suction pressure measured by a pressure sensor provided at a location (not shown) are calculated, and the optimum swing position of the variable lip 9 is adjusted from the performance characteristics of the WJ pump 8 according to the suction pressure. I do.

In this way, the combination of the pressure detector 19 provided on the wall surface of the water intake pipe 6 and the detection angle of the angle detector 15 causes the variable lip 9 to swing to the optimum position.

In this adjustment, when the ship speed is low, the suction pressure is low, so that the variable lip 9 is swung so as to protrude, and the suction pressure increases as the ship speed increases. Therefore, the variable lip 9 is gradually increased as the suction pressure increases. At the time of rated output. As described above, by feeding back the position of the variable lip 9 detected by the angle detector 15, the WJ pump 8 can always be operated at the optimum water intake efficiency required. It should be noted that data other than the suction pressure, such as the state of the sea, may be fed back, thereby making it possible to further optimize the water intake efficiency.

According to the present invention, the angle at which the variable lip 9 swings can be set arbitrarily.
It is also possible to set the angle as shown by the thin line I, and thereby the control range of the water intake efficiency can be widened.

Further, when the variable lip 9 is swung so as to protrude, the opening area of the water intake port 5 can be made larger than the cross-sectional area of the water intake pipe 6, and the area of the water intake port 5 having a large area and a small area can be obtained. Water is introduced into the water intake conduit 6, which is a very good form for increasing the suction pressure.

Since the shape of the variable lip 9 is formed so as to approximate the curved surface of the water pipe 6, the variable lip 9
The water is sucked in smoothly without significantly increasing the resistance of the water that is taken in even if it is swung.

The side fence 18 provided at the bottom of the ship
Serves to prevent water taken in when the variable lip 9 is operated to project from leaking from the side of the variable lip 9.

As described above, the present invention basically uses a flush-type intake port having a small hull resistance, and increases the intake efficiency by using the variable lip 9 provided in the intake port 5 even in a region where the boat speed is low. Thus, it is possible to increase the rotation speed of the WJ pump 8 to increase the generated thrust. Therefore, by adopting the variable intake port H, the acceleration from the hull stop to the rated boat speed is improved, and agile maneuvering becomes possible.

Further, since the conventional water intake pod 51 can be eliminated without lowering the efficiency of the WJ pump 8, the hull 1 can be reduced in weight and the hull resistance can be reduced.
As a result, not only can the speed be increased, but also the fuel consumption of the main engine can be reduced.

In the above-described embodiment, the hydrofoil J in which the submerged body 2 is provided below the hull 1 is taken as an example. However, the submersible body 2 having no submerged body 2 is used. 112
The present invention can be applied to a hull having a hull shape such as that of No. 199.

In the above embodiment, the drive means for swinging the variable lip 9 is constituted by the hydraulic cylinder 12 as an actuator. However, the drive means may be an electric or pneumatic drive means, and is particularly limited. Not something. Further, the connection between the actuator and the drive shaft 10 is not limited to the link mechanism using the operation lever 11.

[0041]

According to the present invention, at low speed, the water intake efficiency is increased by swinging the variable lip provided at the water intake so as to protrude, thereby increasing the rotation speed of the water jet pump to reduce the generated thrust. Can be bigger.

Further, since the variable lip can be stored as the ship speed increases, the hull resistance does not increase. At this time, take out from the lip side by the side fence.
Prevent water leakage and set the suction flow rate according to the amount of protrusion of the lip.
Can be

Further, in accordance with a suction pressure detected by a pressure detector provided on a rear wall surface of the water intake pipe, an optimum variable lip swing angle is adjusted and the position of the variable lip is fed back, so that a water jet pump is provided. Can always be operated at an optimum water intake efficiency, which enables extremely efficient operation of the water jet pump.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing a hydrofoil ship provided with an intake port of the present invention, (a) is a schematic side view, and (b) is a view taken along an arrow AA.

FIG. 2 is an enlarged sectional view showing the water intake of the present invention.

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIGS. 4A and 4B are drawings showing a hydrofoil ship provided with an intake port of Conventional Example 1, wherein FIG. 4A is a schematic side view, and FIG.

FIGS. 5A and 5B are drawings showing a hydrofoil boat provided with an intake port of Conventional Example 2, wherein FIG. 5A is a schematic side view and FIG.

FIG. 6 is a graph showing the relationship between ship speed and hull resistance.

FIG. 7 is a graph showing a relationship between an intake pipe pressure and an allowable pump speed.

FIG. 8 is a graph showing the relationship between the pump rotation speed and the generated thrust.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hull 2 ... Submerged body 3 ... Hydrofoil 4 ... Strut 5 ... Intake port 6 ... Intake line 7 ... Main engine 8 ... Water jet pump 9 ... Variable lip 10 ... Drive shaft 11 ... Operating lever 12 ... Hydraulic cylinder 13 ... Piston 15 ... Angle detector 18 ... Side fence 19 ... Pressure detector H ... Variable water intake J ... Hydroplane W ... Water surface

Claims (2)

(57) [Scope of request for utility model registration] A hull and a submerged body serving as a floating body are struts.
Has a water intake on the bottom of the submerged body of the hydrofoil ship connected by
The water taken in from the intake is taken by the main engine through the intake pipe.
Pressurized by a driven water jet pump and behind the hull
In the water jet inlet of the water jet pump, a drive shaft is provided at the rear of the water inlet, and a variable lip is swingably provided on the drive shaft, and a submerged body is provided on both sides of the variable lip.
Increasing the height gradually with a gentle slope from the front end of the bottom intake
The maximum height is almost at the tip of the variable lip on the side of the intake pipe
From the maximum height position, gradually increasing with a gentle slope.
At a position behind the drive shaft of the variable lip
A variable intake for water jet pumps, characterized by a side fence connected to the bottom of the water body . 2. A water jet pump for said water intake line.
Pressure in the intake pipe at the lower bend of the rear wall connecting to the
Is provided with a pressure detector for detecting
When adjusting to the optimal variable lip swing angle according to the suction pressure
In both cases, the position of the variable lip is fed back to
-Operate the water jet pump with optimal water intake efficiency
The water jet pump according to claim 1, wherein
For variable intake.