JPH0911986A - Water jet propulsion change-over device for ship - Google Patents

Abstract

PURPOSE: To facilitate change-over of advance, stop and retreat by disposing a steering casing surrounding an ejection port of a pump casing and having a drain port in a rear part and providing a change-over valve having a base end part pivotably attached to rear proximity of an opening provided in a bottom surface part of the steering casing. CONSTITUTION: When an advancing ship is stopped, a piston 22 in a cylinder 21 is extended to pivot a change-over valve 17. When the change-over valve 17 is soon pivoted to the erected condition a operating lever provided on the piston 22 abuts against a limit switch to transmit a signal. When the piston 22 is stopped on the basis of the signal, jet flow jetted from a drain port 14 of a steering casing 15 is dammed up by the change-over valve 17 to be jetted right below from a jet 16 to stop the ship. Also, when the ship is moved backward, the piston 22 is further extended to the terminal end to pivot the change- over valve 17 to the backward inclined condition and jet the jet flow from the jet 16 obliquely downward in the advance direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water jet propulsion device for a ship, and more particularly, to an improvement in a propulsion switching device capable of advancing, stopping or retracting a ship while rotating an impeller at high speed.

[0002]

2. Description of the Related Art Conventionally, as a water jet propulsion device, it is described in claim 1 of the specification of Japanese Patent Application Laid-Open No. 5-278683 and from the third page, left column, lines 7 to 32 of FIG. As shown in the figure, the steering cylinder behind the jet nozzle of the propulsion machine is provided with a plurality of commutation plates for diverting the water jet flow forward at the bottom opening of the steering cylinder, and the commutation plates are closed. There has been a propulsion switching device in which a flap for controlling rotation is arranged in a horizontal laid state and an inclined standing state in which the rear opening of the steering cylinder can be closed and the vessel is advanced, stopped, or retracted.

[0003]

However, in the above-mentioned conventional device, the forward and backward movements with less traveling resistance can be switched without decelerating the rotation of the impeller. The commutation plate fixed to the bottom of the was the water flow resistance when moving forward at high speed. It is an object of the present invention to provide a device having a simple structure and a small hull resistance, and which can be easily switched between forward, stop and reverse.

[0004]

SUMMARY OF THE INVENTION The gist of the present invention is a water jet that obtains propulsive force by pressurizing water from a suction port opened at the bottom of a ship by an impeller in a pump casing and injecting the water from an ejection port provided at the stern. In the propulsion device, a steering casing having a discharge port is provided so as to surround the discharge port of the pump casing, an opening is provided at the bottom of the steering casing, and the base end portion is provided near the rear of the opening. A switching valve pivotally attached is provided, and the opening is arranged so that it can be opened and closed.
The inner peripheral surface of the steering casing is formed along the peripheral portion of the rotational locus behind the pivotal attachment portion of the switching valve, and the rotational angle of the switching valve is adjustable.

[0005]

The present invention is configured as described above, and when the impeller is rotated, the water such as seawater sucked into the pump casing is pressurized and accelerated to flow into the steering casing, and from the rear end thereof. It is ejected as a jet flow, and the reaction force of the discharge pressure causes the ship to travel forward. Then, when the switching valve of the steering casing is rotated to the upright state, the opening of the bottom surface portion of the steering casing is opened, and at the same time, the discharge port at the rear portion of the steering casing is closed. The water flow pressurized and accelerated from the pump casing is guided by the surface portion of the switching valve and ejected as a jet flow directly below the opening of the steering casing to stop the ship. Further, when the marine vessel is moved backward, if the switching valve is rotated further to the rearward inclined state, the jet flow is jetted obliquely downward in the forward direction from the bottom surface of the steering casing, and it is possible to switch from full speed forward or stop to reverse. .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on embodiments. First, in FIG. 1, reference numeral 1 is a pump casing arranged at the stern 2 of a ship, and the pump casing 1 is inclined downward in the forward direction. It comprises a suction casing 3, a main body casing 5 in which an impeller 4 is arranged in the horizontal direction, and a discharge casing 6 having a reduced opening rearward. Suction
A screen 8 is provided at the suction port 7 of the casing 3 so as to prevent suction of litter and wood chips. Code 9
Is a rotary shaft, and the impeller 4 arranged on the rotary shaft 9 is driven by the gas turbine 10. If the impeller 4 used in the present invention is preferably composed of two spiral blades as shown in FIG. 1, the water flow sucked into the suction casing 3 due to the rotation of the impeller 4 causes the start end of the spiral blade to be changed. Is fed to the section and transported along a series of twisted guide surfaces, which can be accelerated while being pressurized by the guide surfaces. Reference numeral 11 is a guide vane, which is an inner peripheral surface of the discharge casing 6 and a bearing 12 at the tip of the rotary shaft 9.
Both ends thereof are connected to and so that the vortex flow sucked by the rotation of the impeller 4 is made into a linear flow by the guide blade 11. In addition, since the discharge port 13 of the discharge casing 6 is reduced, even if the impeller 4 is rotated at a high speed, a negative pressure does not occur and cavitation does not occur.

As shown in FIG. 2, a steering casing 15 surrounding the discharge port 13 of the discharge casing 6 and having a discharge port 14 at the rear thereof is provided in the latter stage of the discharge casing 6 as shown in FIG.
Is provided, and the water flow pressurized and accelerated from the discharge port 13 of the discharge casing 6 is supplied to the discharge port 14 of the steering casing 15.
It is designed to be ejected as a jet stream from the vessel to advance the vessel. The jet 16 is provided on the bottom surface of the steering casing 15.
Is provided, and a switching valve 17 having a base end portion pivotally attached is provided near the rear of the ejection port 16, and the switching valve 17 can close the ejection port 16. Reference numeral 18 is a seat provided at the ejection port 16. The steering casing 15 will be described in detail with reference to FIGS. 2 to 5.
Is formed in parallel with the rotation axis of the impeller 4, and the middle stage of the steering casing 15 has an inner peripheral surface at the rear of the pivoting portion of the switching valve 17 for the turning locus of the switching valve 17. It is formed along the circumference. Therefore, when the switching valve 17 of FIG. 3 is rotated from the closed state of the jet outlet 16 of the steering casing 15 of FIG. 2 to the upright state, the inner peripheral surface of the steering casing 15 is sealed so that the discharge port 14 can be closed. The discharge port 14 can be closed in the range in which the switching valve 17 rotates from the upright state to the rearwardly inclined state in FIG. If the steering casing 15 is formed in a rectangular tube shape and the upper wall portion and the bottom surface portion of the switching valve 17 behind the pivot portion are formed along the turning trajectory of the switching valve 17, the injection of the bottom surface portion of the steering casing 15 is performed. The outlet 16 can be easily arranged, and the switching valve 17 may be formed in a square plate shape. The steering casing 15 may be cylindrical, the seat 18 of the ejection port 16 may be flat, and the switching valve 17 may be disk-shaped.

A switching valve 17 whose base end is pivotally attached to the bottom surface of the steering casing 15 is fixed to a drive shaft 19, and the drive shaft 19 is fixed to a link rod 20. On the other hand, on the outer peripheral portion of the steering casing 15, a cylinder 21 is provided, the base end portion of which is rotatably connected, and the tip end of a piston 22 of the cylinder 21 is also pivotally attached to the other end of the link rod 20. . When the piston 22 is contracted, the switching valve 17 comes into close contact with the valve seat 18 of the bottom surface seat of the steering casing 15 to close the ejection port (FIG. 2), and the pressure is increased from the pump casing 1. Water flow is steering casing 1
A jet flow is ejected from the discharge port 14 of No. 5 so that the ship travels forward. When the forward movement of the ship is to be stopped, when the piston 22 is extended, the switching valve 17
Rotates, and the discharge port 16 of the steering casing 15 is opened. When the switching valve 17 is continuously rotated to the upright state (FIG. 3), the rear discharge port 14 is closed, the pressurized and accelerated water flow from the pump casing 1 is blocked, and is guided to the surface portion of the switching valve 17. A jet flow is jetted out from the jet port 16 directly below, so that the ship traveling forward is stopped. When the piston 22 is further extended (FIG. 4), the water flow is guided to the surface portion of the switching valve 17, the jet flow is jetted obliquely downward in the forward direction, and the ship can be retracted.

Next, the rotation control device for the switching valve 17 will be described in detail with reference to FIG.
When the piston 22 is contracted, the link rod 20 rotatably connected to the switching valve 17 is connected to the switching valve 17 as shown in FIG.
4 rotates to close the jet outlet 16 at the bottom of the steering casing 15 and extend the piston 22 to the end.
As shown in FIG. 5, the lengths of the switching valves 17 are set so that the inner surface of the steering casing 15 is sealed in the rearward inclined state. The tip of the piston 22 is shown in FIG.
As shown in FIG. 5, a piston rod 22 connected to an operating rod 23 extending rearward thereof corresponds to the upright state of the switching valve 17.
A limit switch 24 is provided opposite to the cylinder 21 depending on the extended position of the cylinder. When the tip of the operating rod 23 abuts against the limit switch 24 when the piston 21 is extended or stored, the piston 2 is detected by the detection signal.
1 is stopped. Instead of the limit switch 24, the rotation of the switching valve 17 may be controlled by detecting the amount of fluid such as oil supplied to the cylinder 21.

That is, when the contracting piston 22 is extended, the switching valve 17 is rotated to stop the forward ship, and the jet port 16 of the steering casing 15 is rotated.
When the switching valve 17 is rotated to the upright state, the operating rod 23 provided on the piston 22 abuts the limit switch 24 and transmits a detection signal. Then, when the piston 22 is stopped based on the detection signal, the jet flow ejected from the discharge port 14 of the steering casing 15 is blocked by the switching valve 17 which is rotated in the vertical state and is ejected from the ejection port 16 on the bottom surface. It is possible to stop the ship traveling forward by injecting it directly below. When the boat is going to be retracted, the piston 22 is further extended to the terminal end, the switching valve 17 is rotated to the rearward tilted state, and the jet flow can be jetted obliquely downward in the forward direction from the ejection port 16. it can. At this time, the rearward inclination angle of the switching valve 17 is set to 30 to 4
If the lengths of the piston 22 and the link rod 20 are adjusted so as to be inclined by 5 °, the water flow that collides with the switching valve 17 is injected obliquely downward at 30 to 45 ° in the forward direction, and the full speed forward to full speed reverse is achieved. Switching can be done immediately. A pair of propulsion units may be provided at both ends of the stern 2 to turn the ship by operating the switching valve 17, or a pair of cylinders 25 may be provided on both side surfaces of the pump casing 1 and the steering casing 15 for steering. The casing 15 may be moved left and right.

[0011]

The present invention is configured as described above,
By operating the switching valve provided in the steering casing, it is possible to advance, stop or retreat the ship with less vibration and noise while rotating the impeller at high speed. That is, in the conventional device, the traveling switching device which becomes the resistance of the water flow is provided so as to be exposed in the water, but in the present invention, the water flow switching device of the propulsion device is arranged inside the casing. Since the switching valve is installed and is in close contact with the bottom surface of the casing during forward movement, it does not affect jetting of the jet flow. Further, since the shape of the intermediate portion of the steering casing is formed along the turning locus of the switching valve, there is no waste of water flow at the time of stopping and retreating. Moreover, since the member outside the steering casing is also rod-shaped, there is almost no member outside the casing that acts as a resistance to the water flow during traveling, so there is no vibration or noise, and there is little damage during traveling. That is, it is possible to secure safety and riding comfort while reducing energy loss with a simple structure.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a water jet propulsion switching device for a ship according to the present invention.

FIG. 2 is an enlarged vertical cross-sectional view of a main portion of the propulsion switching device according to the present invention when the boat is traveling forward.

FIG. 3 is an enlarged vertical cross-sectional view of a main portion of the propulsion switching device according to the present invention when the ship is stopped.

FIG. 4 is an enlarged vertical cross-sectional view of a main part of the propulsion switching device according to the present invention when traveling in reverse.

FIG. 5 is a main part outline view of the propulsion switching device according to the present invention.

[Explanation of symbols]

 1 Pump casing 2 Stern 4 Impeller 13 Discharge port 14 Discharge port 15 Steering casing 16 Jet port 17 Switching valve

Claims (2)

[Claims] 1. A water jet propulsion device for obtaining propulsive force by pressurizing water by an impeller 4 in a pump casing 1 from a suction port 7 opened at the bottom of the ship and jetting it from a discharge port 13 provided at the stern 2 to obtain a propulsive force. A steering casing 15 that surrounds the discharge port 13 of the pump casing 1 and has a discharge port 14 at the rear portion is provided, an opening 16 is provided in the bottom surface portion of the steering casing 15, and a base end of the steering casing 15 is provided near the rear of the opening 16. A switching valve 17 having a pivotally mounted portion is provided, the opening 16 is arranged to be openable / closable, and the inner peripheral surface of the steering casing 15 is formed along the peripheral portion of the rotation locus behind the pivotal portion of the opening / closing valve 17. A water jet propulsion switching device for a ship, characterized in that the turning angle of the switching valve 17 is adjustable. 2. A water jet propulsion switching device for a ship, characterized in that the switching valve 17 according to claim 1 can be rotationally controlled to an upright state or a rearwardly inclined state.