JP2532236Y2 - Underwater jet pump jet propulsion device - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a propulsion device for a ship propelled by jet stream jetting, particularly when a jet jet nozzle is underwater (hereinafter, referred to as "underwater"). (Also referred to as "spout type").

2. Description of the Related Art In recent years, pump jet propulsion has been used to replace the conventional screw propellers, which are often found on certain ships. Its purpose is to provide high-speed conventional additions: rudder, overhang bearing,
When there is too much to compensate for the difference in propulsion efficiency (screw propeller> pump jet) from the resistance of the supporting strut and propeller drive shaft, etc. It is difficult for conventional screw propellers to absorb the horsepower because of the large horsepower Cases In order to reduce the underwater radiated noise of the thruster There are various cases such as when shallow draft navigation is required.

Here, a typical structural example of the pump jet propulsion is shown in FIG.

In the figure, a drive shaft is connected to a suction port P provided in a ship bottom Hb.
This is a type in which water sucked up by a pump 33 rotated by 32 is slightly lifted and spouted into the air. In the case of this type, the steering device R is provided on the stern side of the jet nozzle 34, and further, a steering duct 36, which is another nozzle like.
By turning the steering duct 36 in a horizontal plane with the fluid axis 35 using the vertical axis 37 as a support axis, the direction of the jet flow is changed to perform the steering function (for example, , JP 50-21492, JP 61-2
No. 57395, JP-A-62-205894, Japanese Utility Model Application Laid-Open No. 50-4488, Japanese Utility Model Application No. 50-38091, Japanese Utility Model Application Laid-Open No. 54-23497).

The steering duct 36 has a feature that it does not come into contact with the jet flow when traveling straight, and has little resistance when traveling straight because it is in the air, which is one of the factors for adopting the above-described jet propulsion device.

(Problems to be Solved by the Invention) However, in the above-described conventional jet propulsion of the air jet method, a loss on resistance around the suction port P, that is, a bending loss of a water flow, a lifting of a water flow, a loss of a water flow, and a maintenance of a static pressure of a pump portion. (Prevention of cavitation) Loss of pipeline and other factors, and many negative factors on propulsion performance.

Then, in order to solve this problem, an underwater jet system in which suction ports are arranged in a straight line can be considered. It is considered that this can be applied by appropriately changing the structure of the air jet system, and FIG. 8 shows an example in which this is applied to a semi-submerged catamaran (hereinafter, referred to as a "SWATH ship").

In FIG. 8, 40 indicates a SWATH ship, 41 indicates its superstructure, 42f and 42a indicate struts, and 43 indicates a lower hull. As shown, the jet nozzle 44 is underwater, but the steering function is achieved by a separate rudder (ladder) R '. However, it is clear that the provision of this rudder increases the propulsion resistance and also provides extra stern structure for mounting the rudder (i.e. struts).
42a). This, in turn, increases the surface area in contact with water, thus increasing the resistance.

In view of such a conventional problem, an object of the present invention is to provide an underwater jet type jet propulsion device having a steering function that does not cause extra resistance loss as much as possible.

(Means for Solving the Problems) In order to achieve the above object, the jet propulsion device according to the present invention is provided with a jet nozzle along the stern hull, and the jet nozzle is provided on the bow side of the jet nozzle with the jet nozzle in a fluidly smooth manner. Submersible jets provided continuously with a hub having an impeller for applying energy to water in a circular casing connected to an inner core and a guide blade for converting a swirling flow into an axial flow at an end of the hub. In the propulsion device of the formula, the jet nozzle is constituted by a circular cylindrical main body and a rear end following the upper and lower walls and both side walls to form a rectangular nozzle discharge port at the rear end, The nozzle side walls are rotatably supported around a substantially vertical axis so as to function as a rudder piece, and the nozzle upper and lower walls and both side walls maintain a rectangular nozzle shape when moving straight, and the nozzle is turned when steering. It is characterized in that a rotating means for rotating both side walls of the chisel within a required angle in a horizontal plane is provided.

(Operation) According to the above configuration, the jet stream is pushed straight backward in the straight direction when the vehicle is going straight, and the steering pieces formed on both walls at the ends of the jet nozzle are rotated at a desired angle by the rotating means during steering. Then, the steering function is exhibited by giving an angle to the direction of the jet flow.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a partially cut-away plan view showing a first embodiment of a submerged jet jet propulsion device according to the present invention, FIG. 2 is a view taken in the direction of arrow X in FIG. 1, and FIG. FIG. 4 is a partially cut plan view showing a second embodiment. In each of the above embodiments, for example, as shown in FIG.
This applies to SWATH vessels.

1, 2 and 3, the end of the hull H,
That is, as shown in FIG. 6, a cylindrical jet nozzle 1 is protruded along the rear end of the lower hull 23. At the rear end of the jet nozzle 1, rudder pieces 2 and 2a constituting a rectangular outlet for discharging a jet jet are pivotally supported around a vertical axis 14 as described later (see FIG. 1). (See FIGS. 2 and 3).

The jet nozzle 1 has a lower hull 23 inside.
The rear end is provided with a rotatable hub 6 connected thereto, and the hub 6 is provided with a plurality of impellers 6a radially. The impeller 6a is configured to be variable, that is, configured as a variable pitch blade, and is responsible for matching against changes in ship speed (change in load), reverse thrust, and the like. Although not shown, a pitch change of the impeller 6a, a drive shaft of the hub 6, and the like are built in the rear end of the lower hull 23.

At the rear end of the hub 6, an inner core 9 is provided continuously with the hub. The inner core 9 has an outer peripheral surface formed in a substantially streamlined shape, and is mounted in the jet nozzle 1. However, the tip portion slightly protrudes from the tip (rear end) of the rudder pieces 2 and 2a in order to obtain the rectifying effect of the jet flow as much as possible. A guide vane 7 protrudes radially from the outer surface of the inner core 9, and its tip is fixed to the inner surface of the jet nozzle 1 and is supported and fixed by the jet nozzle 1. The jet nozzle 1 is supported by a stay (support member; not shown) extending from the hull. The kinetic energy given to the fluid by the impeller 6a is applied to the guide vane 7 having the twist.
And is converted to propulsion energy as much as possible.

Further, since the cross-sectional area of the inlet of the jet nozzle 1 is larger than the area of the outlet, the propulsive force given by the impeller 6a increases the pressure in the jet nozzle 1, and usually has the effect of avoiding cavitation that often occurs in the nozzle. I'm playing.

As described above, the circular jet nozzle 1 has a rectangular discharge port formed at the rear end thereof by the upper and lower walls 10 and 11 and the side walls 2 and 2a (FIG. 2). Also serves as. In addition, as shown in the figure, the corner portion 13 of the discharge port is rounded to minimize the resistance, and
Since no gap is formed between the upper and lower walls 10 and 11 and the side walls (rudder pieces) 2 and 2a at the time of steering, the jet flow does not leak and the efficiency is high. In this case, the flow surface of the jet flow is
It is formed so as to gradually and smoothly continue from the circular jet nozzle 1 to the rectangular discharge port. Reference numeral 12 denotes brackets provided at both ends of the upper and lower walls.

The turning means of the rudder pieces 2 and 2a will be described with reference to FIG. At the rear end of the jet nozzle 1, a flat rudder piece 2 (the rudder piece 2a is on the starboard side) hinged by a vertical shaft 14 is provided, and a servo motor ( Cylinder 5 is pivotally mounted. That is, the base end is pivotally attached to the jet nozzle 1 side, and the rod is pivotally attached to the rudder piece 2 side, so that the position of the rudder piece 2 can be changed by the expansion and contraction of the rod. The operation of the servo motor 5 is linked with the steering wheel in the ship's wheelhouse.

In FIG. 3, the position A is when the vehicle is traveling straight, and the positions B and C are shown.
The position indicates the time of turning. Reference numerals 3 and 4 denote fairing covers of the servomotor 5, which are formed in a streamline shape so as not to cause an increase in resistance due to a protrusion such as the servomotor 5. The front end of the fairing cover 4 is formed slightly inside the rear end of the fairing cover 3 in consideration of the swing of the rudder piece 2.

Next, the steering function of the jet propulsion device will be described with reference to FIGS. 5 (a) and 5 (b).

FIG. 5 (a) shows a state in which the vehicle is traveling straight ahead.
2a is at the position A in FIG. In this state, the water flow is ejected straight and smoothly along the inner surface of the jet nozzle 1 and the outer surface of the inner core 9.

FIG. 5 (b) shows the steered state, in which the port side rudder piece 2 rotates inward (swings) by the operation of the servomotor 5.
The starboard-side rudder piece 2a is turned (swinged) outward. For this reason, the jet stream is jetted at an angle θ from the center line as a whole. As a result, a lateral thrust is generated by Tsinθ of the jet thrust T, and the ship turns right. That is, the steering function can be provided by the function of the steering piece 2 and the steering piece 2a.

Next, a second embodiment of the present invention will be described with reference to FIG.

As apparent from FIG. 5 (b), the jet flow in the steered state hits the tip of the inner core 9 and the water flow may be disturbed, and the steering performance may be deteriorated accordingly. .

Therefore, as shown in FIG. 4, the inner core 9 is composed of a base portion 9a and a rotating portion 9b at the distal end thereof, and the base end of the rotating portion 9b is formed in a hemispherical shape. The parts are fitted and slidably contacted with each other, and are pivotally supported by pins 9c. With this configuration, when the jet stream hits the rotating portion 9b at the tip, the jet stream rotates in the direction of the water stream, achieving smooth jet without disturbing the jet stream, and the jet angle θ of the jet stream. And a larger steering force (lateral thrust) can be obtained. Thereby, the steering performance is improved.

As shown in FIG. 6, when the underwater jet type jet propulsion device according to the present invention is applied to a SWATH ship 20, a normal rudder (see FIG. 8) is not required as shown in FIG. 6 (a). Accordingly, the rear strut 22a can be made smaller. As a result, since the water contact surface area can be reduced, the resistance is also reduced and the propulsion performance is improved.

21 is the upper structure, 22f is the front strut, 23
Indicates lower hal, and W indicates a water line.

(Effects of the Invention) As described above, according to the present invention, an underwater jet type jet propulsion device with high propulsion efficiency can be achieved. Moreover, since the steering device is provided with this, for example, when the present invention is applied to a SWATH ship, a normal rudder becomes unnecessary, and the struts supporting the rudder can be made smaller. The surface area can be reduced, and the propulsion resistance can be reduced accordingly. And a high-speed ship (boat) excellent in propulsion performance, which cannot be obtained with a conventional spiral (screw propeller) propulsion device, can be obtained.

[Brief description of the drawings]

1 to 6 are views showing an embodiment of the present invention, and FIG. 1 is a partially cutaway view showing a first embodiment of an underwater jet type jet propulsion device according to the present invention. FIG. 2 is a plan view, FIG. 2 is a view taken in the direction of arrow X in FIG. 1, FIG. 3 is an enlarged view of a main part of FIG. 1, FIG.
5 (a) and 5 (b) are explanatory diagrams of the steering function, and FIG. 6 (a)
(B) is a drawing in which the device of the present invention is applied to a SWATH ship. FIG. 7 is a side view of a conventional air-jet type jet propulsion device, and FIG.
This is a drawing when applied to ATH vessels. 1 ... jet nozzle, 2 and 2a ... rudder piece, 3 and 4 ... fairing cover 5 ... servo motor 6 ... hub, 6a ... impeller, 7 ... guide vane, 9 ...
... inner core, 14 ... vertical axis, H ... hull.

Claims (1)

(57) [Scope of request for utility model registration] 1. A jet nozzle is provided along a stern hull,
A hub having an impeller for applying energy to water in a circular casing fluidly and smoothly connected to the jet nozzle at the bow side of the jet nozzle, and a hub for converting a swirling flow into an axial flow at an end of the hub. In an underwater jet type propulsion device provided with an inner core to which guide vanes are continuously provided, the jet nozzle is constituted by a circular cylindrical main body and upper and lower walls and both side walls at a rear end following the main body. While forming a rectangular nozzle discharge port at the rear end, the nozzle side wall is rotatably pivoted about a substantially vertical axis so as to function also as a rudder piece, and the nozzle upper and lower walls when straight ahead. An underwater jet pump jet propulsion device comprising: a rotating means for maintaining a rectangular nozzle shape with both side walls and rotating the nozzle both side walls within a required angle in a horizontal plane during steering.