JPH08310479A - Backward gear of water jet boat - Google Patents

Abstract

PURPOSE: To secure a astern device of a water jet boat, capable of securing efficient and large backing power, and being good in appearance, aside from high performance and inexpensiveness. CONSTITUTION: In this water jet boat which takes a flow of external seawater from a seawater intake 6 installed in a seawater submerged surface nearby the bow and, after this seawater is pressurized by a variable pitch axial flow pump 2 inserted into the rear end of a main duct 5, it is discharged to the rear from a rear end opening 10 of the duct, whereby being advanced forward, it is provided with a branch duct 8 being branched off from a branch port 8a to be opened upward a little the variable pitch axial flow pump 2, and having a louver 7 extending somewhat in the heading direction and opening to the side shell. In time of going astern, the branch port 8a is fully opened, while air is taken out of the rear end opening 10, and this air is exhausted from side to rear of the hull from the louver 7 by way of a rear end of the main duct 5 and the branch duct 8, whereby the hull is made to go astern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reverse device for a water jet ship.

[0002]

2. Description of the Related Art In a water jet ship which is a high speed ship,
FIG. 8 is a vertical cross-sectional view of the propulsion device when the ship moves backward.
In, the nozzle 012 mounted on the axial flow pump 02 and the reverse traveling bucket 011 are rearranged by a rearrangement mechanism, and the seawater in the duct is drained from the bucket 011 forward and downward as indicated by the arrow, whereby the rearward propulsion is performed. It is gaining strength and is moving backwards.

[0003]

However, in such a reverse drive means, the hull receives a forward force for pumping seawater from the front, which causes resistance during reverse drive, which is inefficient. However, it has a drawback that it cannot obtain a large driving force. Furthermore, the appearance is not very good because a large nozzle and a bucket must be provided at the stern.

The present invention has been proposed in view of such circumstances, and provides a high-performance economical water jet ship reverse device that can obtain a large reverse force with good efficiency and does not look bad. The purpose is to do.

[0005]

In order to achieve such an object, the invention according to claim 1 takes outside seawater from a main duct seawater intake provided on a seawater immersion surface near the bow of the stern. Is a water jet ship in which a variable pitch axial flow pump inserted at the rear end of the main duct is used to advance the water by discharging it backward from the rear end opening above the water surface of the main duct. A water jet comprising a branch duct having a louver that branches from a branch opening that opens slightly upstream of the variable pitch axial flow pump on the upper surface of the ship and has a front end that extends slightly in the bow direction and that opens to the freeboard of the outer shell of the ship. On the ship, the pitch of the coaxial flow pump was changed during backward movement to take in outside air from the rear end opening of the ship and passed through the branch duct to the deflector louver. It characterized by reverse hull by venting laterally-forward Luo hull.

According to a second aspect of the present invention, external seawater is taken in from a main duct seawater intake port provided on the seawater immersion surface near the bow of the stern, and this is added by a fixed pitch axial flow pump inserted in the rear end portion. A water jet ship that is designed to move forward after being pressurized and then drained rearward from the rear end opening above the water surface of the main duct, and slightly upstream of the fixed pitch axial flow pump on the upper surface of the main duct. Reversing the fixed-pitch axial flow pump when going backward in a water jet ship that has a branch duct with a louver that branches off from the opening and has its front end slightly extended in the bow direction and opens on the freeboard of the outer shell of the ship. The outside air is taken in through the main duct from the rear end opening and is exhausted from the louver to the side to the front of the hull via the branch duct. Characterized in that it reverse the hull Ri.

According to the third aspect of the present invention, external seawater is taken from the main duct seawater intake provided on the seawater immersion surface near the bow of the stern, and this is added by a variable pitch axial flow pump inserted at the rear end. In a water jet ship that is designed to move forward after being pressurized and then drained rearward from the rear end opening above the water surface of the main duct, above the outside of the main duct and slightly ahead of the variable pitch axial flow pump. When the front end of the branch opening is pivoted by a hinge and the rear end moves upward to the outside, the front end of the branch opening slightly extends in the bow direction and opens to the outer shell of the ship. When the rear opening is fully closed and the rear end moves in the opposite direction to the above direction, the branch opening is fully opened and a switching valve that shuts off the main duct with the line at the front end of the branch opening is provided. The switching valve fully opens the branch opening and at the same time shuts off the main duct, changes the variable pitch of the variable pitch axial flow pump, and takes in atmospheric air from the rear end opening of the main duct, which is then passed through the branch duct. It is characterized in that the hull is moved backward by exhausting air from the louver at the open end of the outer plate to the side to the front of the hull.

According to a fourth aspect of the present invention, the reverse gears of the third aspect are arranged side-by-side symmetrically along both sides of the hull, and exhaust air from the port side branch duct and the starboard side branch duct is set in reverse. Is exhausted from the port side louver and the starboard side louver to the side to the front of the hull.

According to a fifth aspect of the present invention, in the third aspect, the common main duct part of the water jet advancing device and the air jet reverse device is disposed on the center line of the hull, and the left and right port sides branch from the common main duct part. A louver is provided at the front end opening of each branch duct near each side to exhaust the exhaust air from the side to the front of the hull to move the hull backward.

According to a sixth aspect of the present invention, in the third, fourth or fifth aspect, a fixed pitch axial flow pump is provided instead of the variable pitch axial flow pump, and the fixed pitch axial flow pump is reversed when the vehicle is traveling in reverse. It is characterized by

[0011]

According to such a construction, in the catamaran having the structure shown in FIG. 1, the moving cover 9A is rotated in the direction of the arrow to the broken line position so that the louver at the end of the branch duct is located behind the main duct 5. While communicating with the end opening 10, the pitch of the variable-pitch axial flow pump 2 is changed, or in the case of a fixed-pitch axial flow pump, the rotation direction is reversed and the main duct 5
Atmosphere is taken in from the rear end opening 10, and air is discharged from the louver 7 to the front to the side through the branch opening and the branch duct 8 to obtain a backward force. Here, in the catamaran having the structure shown in FIGS. 2 to 5, the switching valve 9B shuts off the main duct 5 along the front end line of the branch opening, and the branch duct 8 communicates with the main duct 5. Then, in the same manner, the air taken in from the rear end opening by the axial flow pump is discharged from the louver 7 to the front to the side and moves backward.

Next, in the single-hull type water jet ship shown in FIG. 6, the pitch of the variable pitch axial flow pump is changed,
Alternatively, the fixed-pitch axial flow pump is reversed, and the outside air is sucked in from the rear end opening of the main duct arranged on the stern center line, and after being pressurized by the axial flow pump, it is paired on the left and right side port side ducts. , It diverts to the starboard side branch duct, and goes backward by exhausting from port side and starboard side louvers, which are respectively provided on the freeboard side of the port side and starboard side shell plates, to the side to the front.

[0013]

Embodiments of the present invention will now be described with reference to the drawings.
FIG. 1 is a diagram showing a first embodiment in which the present invention is applied to the backward movement of an air jet of a catamaran. FIG. 1 (A) and FIG. 1 (B) are longitudinal sectional views and transverse sectional views, respectively, and FIG. FIG. 3 is a horizontal cross-sectional view showing a second embodiment of the present invention, FIG. 3 is a horizontal cross-sectional view taken along the line III-III in FIG. 2, and FIG. 4 is a partial horizontal view showing the air flow in the main duct and the branch duct in reverse in FIG. Sectional drawing, FIG. 5 is a horizontal sectional view showing the state of the switching valve switched to the forward direction and the water flow in the main duct in FIG. 4, and FIG. 6 is a third embodiment in which the present invention is applied on the hull centerline of a monohull. And FIG. 7 is a front view showing a fourth embodiment in which the present invention is applied to both sides of a monohull.

First, the first embodiment is an example in which an air jet is applied to a catamaran to make it possible to reverse, and in the longitudinal sectional view of FIG. A variable pitch shaft that is mounted coaxially on the rear end openings 10 of a pair of left and right irregularly-shaped V-shaped main ducts that are parallel to the ship side and that are slightly curved so that the latter half of each part approaches the ship side. It is a flow pump, and by changing the pitch of the blades without changing the number of rotations, seawater is sucked from the water intake 6 at the front end of the main duct 5 and forwarded from the water drain 10 at the rear end as a water pump during forward movement. When the vehicle moves backward, the pitch of the axial flow pump is changed to act as a blower, which sucks the outside air from the rear end drainage port 10 and discharges it from the louver 7 through the branch duct 8 to the front to the side. Numerals 7 are louvers that are respectively disposed on the outer shell of the ship and discharge air from the front end opening of the branch duct 8 which will be described later when moving backward. When moving forward, the louvers 7 are fully closed to move forward. To prevent air from flowing into the variable pitch propeller 3. 8 has a front end opening connected to the louver 7, and a rear end opening of the main duct 5
A pair of left and right branch ducts connected to branch openings 8a formed immediately in front of the variable pitch axial flow pump 2 built in the rear part of the louver 7, and the louver 7 extends the air flow blown out from the front end opening in the range from the front to the side. It can be oriented in any desired direction.

Next, FIGS. 2 to 3 show a catamaran of the second embodiment, in which jet propulsion devices on each port are each formed with a branch opening 8a above the main duct 5.
Reference numeral 9A denotes an on-off valve attached to the branch opening 8a of the branch duct 8, the front end of which is pivotally attached to the front end of the branch opening 8a, and when it is rotated to the solid line position, the branch opening 8a is fully closed and is placed at the broken line position. When it is rotated, it is fully opened and at the same time, the main duct 5 is blocked by the line at the front end of the branch opening 8a. The on-off valve 9A fully closes the branch opening 8a to prevent the jet water flowing through the main duct 5 from entering the branch duct 8 when the vehicle is moving forward, and the backward air from the drain to the branch duct 8 when moving backward. Acts to introduce. Since the structure for mounting the opening / closing valve 9 on the branch opening 8a is a pivotal structure with a horizontal axis hinge at its front end, the opening / closing valve 9A is pushed by water pressure so as to block the branch opening 8a during forward movement, so that water pressure is not applied. When there is no reverse air pressure or when backward air pressure is applied, it is possible to open the branch opening 8a by falling due to the action of negative pressure and its own weight. The opening / closing mechanism may be a hydraulic type.

According to such a water jet propulsion device, as shown in FIG. 4, when the vehicle is moving backward, the pitch of the variable pitch axial flow pump 2 is changed so that the external air flows from the rear end drainage opening 10 into the main duct 5 by an arrow. Is discharged in the direction from side to front through the branch duct 8 and the deflector louver 7 at the tip thereof as shown by the arrow from the branch opening 8a that is fully opened along the on-off valve 9A that has been sucked in the direction and switched to the position that shuts off the main duct. To be done. The reaction of the air flow at that time allows the ship to move backward.

Further, according to such a water jet propulsion device, as shown in the rear view of FIG. 5, the on-off valve 9A is closed during forward movement, and the suction action of the axial flow pump 2 or 3 draws water into the main duct 5. The seawater flowing in from the port 6 flows in the direction of the arrow and is discharged rearward from the rear end drainage port 10, so that the reaction moves the ship forward.

When the jet propulsion device of the present invention is applied to a monohull, as shown in the rear view of FIG. 6, the jet propulsion device is mounted on the center line of the hull, and seawater introduced into the main duct from the intake port on the center line of the hull is introduced. It moves forward by draining backward from the rear end drainage ports 10 of the left and right branch ducts. Further, by changing the pitch of the variable-pitch axial flow pump or reversing the fixed-pitch axial flow pump, the outside air is sucked from the rear end drainage port 10, and the outside air is discharged from the louvers that are respectively opened to the outer plates of both ships, from side to front. To go backwards.

Further, as shown in the rear view of FIG. 7, the jet propulsion device of the present invention is installed on both sides of a monohull in parallel with each other, and during reverse travel, the air introduced from the rear end drainage port on the port side is the louver on the port side. Therefore, the air introduced from the starboard side rear end drainage port is discharged from the starboard side louver. INDUSTRIAL APPLICABILITY The jet propulsion device of the present invention can function as an opening / closing valve if the louver can be fully closed, regardless of whether it is applied to a catamaran or a monohull, and therefore the opening / closing valve of the branch opening is Not necessarily required. This is because the introduced air pressure when moving backward is relatively small, so there is no fear of pushing the water in the main duct to the outside through the water inlet. However, in the case where the vehicle travels backward using strong air pressure, an on-off valve must be installed.

[0020]

EFFECT OF THE INVENTION By changing the simple structure such as mounting the variable pitch propeller, the moving cover and the branch duct, it is possible to efficiently obtain a large reverse force, and by eliminating the bucket, the appearance of the ship is improved.

In summary, according to the first aspect of the invention, the external seawater is taken in from the main duct seawater intake provided on the seawater immersion surface near the bow of the stern, and the variable pitch axial flow is inserted into the rear end of the seawater. A water jet ship, which is pressurized by a pump and then advanced by draining backward from a rear end opening above the water surface of the main duct,
A branch duct having a louver that branches from a branch opening that opens slightly upstream of the variable pitch axial flow pump on the upper surface of the main duct and that has a front end that extends slightly in the bow direction and opens in the freeboard of the side plate of the ship is provided. In a water jet ship, the outside air is taken in from the rear end opening by changing the pitch of the coaxial flow pump when moving backward, and this is passed from the deflector louver to the side of the hull through the branch duct.
By moving the hull backwards by exhausting forward,
It is possible to obtain a large reverse power with good efficiency,
The present invention is of great industrial benefit because it provides a high performance, economical water jet ship reverse drive that does not look bad.

According to the second aspect of the present invention, the fixed-pitch axial flow pump in which the external seawater is taken from the main duct seawater intake port provided on the seawater immersion surface near the bow of the stern and which is inserted at the rear end thereof It is a water jet ship that is made to move forward after being pressurized by the main duct and then drained backward from the rear end opening above the water surface of the main duct. In a water jet ship equipped with a branch duct having a louver that branches from the branch opening that opens upstream and extends slightly toward the bow toward the freeboard of the outer shell of the ship, reverses the fixed-pitch axial flow pump when moving backward. By doing so, outside air is taken in from the rear end opening through the main duct, and is exhausted from the louver through the branch duct to the side to the front of the hull. Claim hull by reverse, at a relatively low cost of the fixed pitch axial flow pump by a 1
The present invention is extremely useful industrially because it can produce substantially the same effect as the above effect.

According to the third aspect of the present invention, the variable-pitch axial flow pump is configured to take in external seawater from the main duct seawater intake port provided on the seawater immersion surface near the bow of the stern and insert the external seawater into the rear end thereof. In a water jet ship that is pressurized by the above, and then forwards by draining backward from the rear end opening above the water surface of the main duct, above the main duct to outside the main duct and some of the variable pitch axial flow pump. A branch duct that branches from the branch opening that opens to the front, and the front end extends slightly toward the bow and opens to the outer shell of the ship, and the front end of the branch opening is hinged to the front end, and the rear end moves upward and outward. In this case, the branch opening is fully closed, and when the rear end moves in the direction opposite to the above, the branch opening is fully opened and the main duct is shut off at the front end line of the branch opening. At the same time, the main switching duct is fully opened and the main duct is shut off at the same time, and the variable pitch of the variable pitch axial flow pump is changed to take in air from the rear end opening of the main duct. From the louver at the open end of the outer plate through the side of the hull ~
By letting the hull move backward by exhausting it forward, a large backward force can be obtained with good efficiency, and a high-performance economical water jet backward device that does not look bad is obtained. The invention is extremely useful in industry.

According to the invention of claim 4, the reverse devices of claim 3 are arranged side by side symmetrically along both sides of the hull,
When moving backward, exhaust air from the port side branch duct and starboard side branch duct is exhausted from the port side louver and starboard side louver to the side to the front of the hull, respectively. The present invention is of great industrial benefit because it provides an economical water jet ship reverse gear.

According to the invention of claim 5, in claim 3, the common main duct part of the water jet advancing device and the air jet reverse device is disposed on the center line of the hull and branched from the common main duct part. Louvers are installed at the front end openings of the branch ducts on the left and right sides, respectively, and the exhaust is exhausted from the side to the front of the hull to move the hull backwards. The present invention is of great industrial benefit because it provides a reverse gear for a single-jet waterjet ship that is economical in performance.

According to a sixth aspect of the present invention, in the third, fourth or fifth aspect, a fixed pitch axial flow pump is provided instead of the variable pitch axial flow pump, and the fixed pitch axial flow pump is reversed during reverse travel. By doing so, the present invention is extremely useful industrially because it provides a relatively low-cost, high-performance economical water jet ship reverse drive that does not look bad.

[Brief description of drawings]

FIG. 1 shows a first embodiment in which the present invention is applied to the backward movement of an air jet of a catamaran. FIG. 1 (A) is a longitudinal sectional view of the same, and FIG. 1 (B) is its port side BB arrow. FIG.

FIG. 2 is a cross-sectional view showing an air jet ship of a catamaran different from FIG.

FIG. 3 is a horizontal cross-sectional view taken along the line III-III of FIG.

FIG. 4 is an enlarged view showing a state of airflow when the jet propulsion device on the port side of FIG. 3 is moving backward.

FIG. 5 is a horizontal cross-sectional view showing the state of the switching valve switched to the forward direction and the water flow in the main duct in FIG.

FIG. 6 is a second example in which the present invention is applied to the centerline of a hull of a monohull.
It is a partial cross section rear view which shows an Example.

FIG. 7 is a partial sectional front view showing a third embodiment in which the present invention is applied to both sides of a monohull.

FIG. 8 is a side view showing a reverse device of a conventional water jet ship.

[Explanation of symbols]

 1 Hull 2 Variable Pitch Axial Flow Pump 3 Impeller 4 Pump Shaft 5 Main Duct 6 Intake Port 7 Louver 8a Branch Opening 8 Branch Duct 9A Moving Cover 9B Open / Close Valve 10 Rear Draining Opening (Rear Opening)

Claims (6)

[Claims] 1. A main duct seawater intake port provided on a seawater immersion surface near the bow of the stern part, where external seawater is taken in, pressurized by a variable pitch axial flow pump inserted at the rear end thereof, and then the main part A water jet ship that is designed to move forward by draining backward from the rear end opening above the water surface of the duct, and from a branch opening that opens slightly upstream of the variable pitch axial flow pump on the upper surface of the main duct. In a water jet ship that is branched and has a branch duct that extends slightly toward the bow and has a louver that opens to the freeboard of the outer shell of the ship, from the rear end opening by changing the pitch of the coaxial flow pump when moving backward. Characterized by taking in outside air and exhausting it from the deflector louver to the side to the front of the hull through the same branch duct to move the hull backward. How to reverse the water jet ship. 2. External seawater is taken in from a main duct seawater intake provided in a seawater immersion surface near the bow of the stern, and the main seawater is pressurized by a fixed pitch axial flow pump inserted at the rear end of the main seawater. A water jet ship that is designed to move forward by draining backward from the rear end opening above the water surface of the duct, and from a branch opening that opens slightly upstream of the fixed pitch axial flow pump on the upper surface of the main duct. In a water jet ship equipped with a branch duct having a louver that branches and the front end extends slightly toward the bow and opens to the freeboard of the side plate of the ship, the fixed-pitch axial flow pump is reversed when the vehicle goes backward, and the rear end is opened. To take in outside air from the main duct through the main duct, and exhaust it from the louver to the side to the front of the hull through the branch duct to move the hull backward. A reverse method of a water jet ship, which is characterized in that 3. The main duct seawater intake is taken from a main duct seawater intake port provided on the seawater immersion surface near the bow of the stern, and is pressurized by a variable pitch axial flow pump inserted at the rear end of the main seawater intake port. In a water jet ship that is designed to move forward by draining backward from the rear end opening above the water surface of the duct, from the branch opening that is above the main duct to outside the main duct and slightly ahead of the variable pitch axial flow pump. A branch duct that diverges and the front end extends slightly toward the bow and opens to the outer shell of the ship, and the front end of the branch opening is hinged to the front end, and when the rear end moves upward or outward, the entire branch opening is opened. When the valve is closed and the rear end moves in the opposite direction to the above, it has a switching valve that fully opens the branch opening and shuts off the main duct at the front end line of the branch opening. At the same time as the branch opening is fully opened, the main duct is shut off, the variable pitch of the variable pitch axial flow pump is changed, and the atmosphere is taken in from the rear end opening of the main duct. A backward device for a water jet ship, characterized in that the hull is moved backward by exhausting air from the louver to the side to the front of the hull. 4. The reverse device according to claim 3 is arranged side-by-side symmetrically along both sides of the hull, and exhausts from the port-side branch duct and starboard-side branch duct are respectively ported to the port-side louvers. , A backward-traveling device for a catamaran type water jet ship, which exhausts from the starboard louver to the side to the front of the hull. 5. The branch duct of claim 3, wherein the common main duct portion of the water jet advancing device and the air jet rearward moving device is arranged on the center line of the hull, and the branch ducts on the left and right sides are branched from the common main duct portion. 2. A reverse traveling device for a single-body type water jet ship, characterized in that a louver is arranged at each of the front end openings of the hull so that the exhaust gas is exhausted from the side to the front of the hull to move the hull backward. 6. The variable pitch axial flow pump according to claim 3, 4 or 5, wherein a fixed pitch axial flow pump is provided instead of the variable pitch axial flow pump, and the fixed pitch axial flow pump is reversed during reverse travel. Reverse device for water jet ships.