JPH05213273A - Astern device for water jet propelling device - Google Patents

Abstract

PURPOSE:To provide an astern device which can smoothly change over going ahead and astern motions by dividing a inside flap into two parts to sharply decrease force required for closing the inside flap. CONSTITUTION:An opening section 4 is provided on the lower face of a nozzle pipe 3 which is connected with a pump 1 and has an outlet passage opened toward the back side of a ship, and an inside flap 5 and an outside bucket 6 are severally arrangedly provided so that the opening section may be closed on the inside and outside of the nozzle pipe 3. The inside flap is divided into an upper and a lower part. The one side ends of the upper and lower flaps 5a, 5b are severally rotatably supported by the upper and lower parts of the nozzle pipe 3, and both the flaps are connected with a U-shaped link mechanism L so that they may rotate simultaneously and in the same direction respectively to compose a balance-type astern device, and the link mechanism L is actuated to open and close the outlet passage by both the flaps according to the ahead and astern states of the ship.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a water jet propulsion device for ships, and more particularly to a reverse drive device for a water jet propulsion device in which the operating force of an inner flap when switching between forward and reverse travel is drastically reduced.

[0002]

2. Description of the Related Art Conventionally, as a reverse device of this type of water injection propulsion device, for example, Japanese Patent Publication No. 32963 as shown in FIG.
There is one described in Japanese Patent No.

As shown in FIG. 5, a nozzle pipe 23 projects from the outlet 22 side of the pump 21 attached to the stern hull H. An opening 24 is formed on the lower surface of the nozzle tube 23. An inner flap 25 and an outer bucket 26 are arranged so as to close the opening 24 from the inner and outer sides of the nozzle tube 23. Inner flap 25 and outer bucket 2
An interlocking device 27 and an operating cylinder 28 are connected to 6.

FIG. 5 (solid line) shows the backward movement of the ship, in which the expansion of the working cylinder 28 raises the inner flap 25 to close the outlet passage 23a of the nozzle pipe 23, and the water ejected from the pump 21 is directed to the inner side. The flap 25 hits the flap 25, is turned downward, and is ejected from the opening 24 through the descending outer bucket 26 to the front lower part as shown by an arrow to generate reverse thrust.

At the time of switching the forward movement, the inner cylinder 25 and the interlocking device 27 connected thereto move the inner flap 25 downward while rotating clockwise about the swivel shaft 25a to close the opening 24, and at the same time, the outer bucket 26 is closed. While rotating counterclockwise, it rises and moves to a position along the lower surface of the nozzle tube 23 in a form in which the inner flap 25 is accommodated. Then, the nozzle pipe has no obstruction in the outlet passage 23. Therefore, the water jetted from the pump 21 passes through the nozzle pipe 23 without being obstructed, and is ejected rearward from the outlet passage 23a to obtain forward thrust.

[0006]

The above-mentioned prior art has the following problems when switching from the backward drive to the forward drive. That is, as shown in FIG. 6, in the reverse drive state, all the total water pressure (resulting force) F from the pump outlet 22 acts on the inner flap 25 as shown by the arrow, and in order to switch from this to the forward drive state, Representative radius R for total water pressure F
The inner flap 25 must be pushed clockwise by the moment F / R multiplied by (distance between the swivel axis 25a of the inner flap 25 and the total water pressure F) to bring it into a horizontal state and close the opening 24. This operation is performed by the pump 21
Since it must be performed directly against the discharge water pressure of No. 2, extremely large force is required. Especially, when the pump 21 has high performance and the water pressure becomes high, the load on the working cylinder 28 for moving the inner flap 25 increases accordingly. Furthermore, FIG.
In the reverse drive state shown in Fig. 7, the water pressure is also acting almost vertically on the outer bucket 26, and in order to switch this to the forward drive state, the outer bucket 26 must be lifted counterclockwise against this water pressure. Similarly, working cylinder 2
It becomes a big burden of 8.

The object of the present invention is to drastically reduce the force required to close the inner flap by devising the structure of the inner flap portion, and also to reduce the external force required to lift the outer bucket, if necessary. Therefore, it is to obtain a reverse device of a water jet propulsion device which can easily perform a forward / reverse switching operation.

[0008]

To achieve the above object, a reverse device for a water jet propulsion device according to the present invention is provided with an opening at the lower surface of a nozzle pipe which is connected to a pump and has an outlet passage opened at the rear of a ship. In a water jet propulsion device having an inner flap and an outer bucket, which are arranged so as to close the opening from the inner and outer sides of the nozzle tube, the inner flap is divided into upper and lower parts, and an upper flap and a lower flap are provided. And one end of the upper flap is pivotally supported on the upper part of the nozzle tube, and one end of the lower flap is pivotally supported on the lower part of the nozzle tube, so that the two upper and lower flaps are simultaneously rotated in the same direction. It is characterized in that it is connected to a link mechanism so as to open and close the outlet passage by both flaps according to the forward and backward traveling state by the operation of the link mechanism. Further, in the above structure, bridges are installed above the both side walls of the outer bucket, and when the outer bucket rises during forward movement, the bridge and the lower flap close the opening on the lower surface of the nozzle tube.

[0009]

In the above structure, as shown in FIG. 3, the total water pressure F from the pump is determined by the upper flap and the lower flap (hereinafter,
(Also called upper and lower flaps) are assigned F / 2 each,
The representative radius r around the axis is R / 2 in the conventional example (FIG. 6), and the moment per flap acting on the axis is F · r = F / 2 · R / 2 = F · R
/ 4, and the directions of this moment are opposite to each other. On the other hand, the upper and lower flaps are connected by a drive lever and a connecting link forming a link mechanism so that they can rotate only in the same direction. Therefore, the upper and lower flaps are balanced like a balance with respect to the division of water pressure F / 2. When switching this to the forward position, the upper flap is rotated backward and the lower flap is rotated clockwise so that they are horizontal as described above to open the nozzle pipe outlet passage. Is sufficient to break the above balance,
As compared with the conventional case where the total water pressure F is opposed as shown in FIG. 5, it can be moved remarkably quickly and lightly. Further, as shown in FIG. 2, when the outer bucket rises during forward movement of the bridge, the lower flap closes the remaining opening area that closes this opening at the opening on the lower surface of the nozzle pipe, so that the jet water from the pump is discharged. To prevent it from unnecessarily leaking to the lower part, it descends together with the outer bucket during reverse travel to ensure a sufficient opening area for the opening.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view of the essential portions of a first embodiment of the device of the present invention, in which the solid line shows the forward traveling state and the phantom line shows the backward traveling state. 2 (a), (b) and (c) are partial side sectional views in FIG. 1, where (a) shows a forward state, (b) shows a neutral state, and (c) shows a reverse state. FIG. 3 is an action diagram of the fluid force in the backward movement state of the device of the present invention.

In these drawings, a nozzle pipe 3 is provided on the outlet 2 side of the pump 1 attached to the hull H so as to be continuous with the outlet 2. An opening 4 is formed on the lower surface of the nozzle tube 3. The front end of the nozzle tube 3 is rotatably supported by a bracket 1a that horizontally protrudes from the pump casing 1A so as to be horizontally rotatable about a swivel shaft 3b.
A horizontal turning mechanism of the nozzle tube 3 necessary for steering the ship is formed.

As shown in FIG. 2, an inner flap 5 and an outer bucket 6 are pivotally attached to the rear end of the nozzle tube 3. The inner flap 5 is divided into upper and lower parts and is composed of an upper flap 5a and a lower flap 5b. The upper flap 5a has its upper end pivotally supported near the upper surface of the nozzle tube 3, and the lower flap 5b has its lower end pivotally supported near the lower surface of the nozzle tube 3, and both flaps 5a and 5b are rotatable shafts 5ao and 5bo, respectively. It is configured to be rotatable around.

As shown in FIG. 2 (a), the lower flap 5b has an opening 4 on the lower surface of the nozzle tube 3 in its horizontal position.
The upper flap 5a and the lower flap 5b are configured to simultaneously rotate in the same direction by the action of a link mechanism L described later. That is, the free ends of the upper and lower flaps 5a, 5b are close to each other and close the outlet passage 3a of the nozzle tube 3 when moving backward, and are separated from each other when moving forward, and the outlet passage 3 of the nozzle tube 3 is moved away from each other.
A can be opened.

Now, the link mechanism L will be described in detail.
The link mechanism L includes a first drive lever 7 and a second drive lever 9
And the connecting link 10 is formed into a substantially U-shaped link mechanism. That is, the rotating shaft 5ao of the upper flap 5a
A base end portion of a three-pronged (anchor) -shaped first drive lever 7 composed of upper, middle, and lower levers 7a, 7b, and 7c is fixed to the upper lever 7a, and a hydraulic pressure to be driven when switching between forward and reverse is applied to the upper lever 7a. The rod ends of the working cylinder 8 that is used as a power source for the above are connected. The cylinder portion of the working cylinder 8 is pivotally attached to a bracket 8a protruding from the top of the nozzle tube 3. On the other hand, a base end portion of a rod-shaped second drive lever 9 is fixed to a rotary shaft 5bo of the lower flap 5b, and the tip end portion of the rod-shaped second drive lever 9 and the first drive lever 7 are fixed. The tip of the middle lever 7b is pivotally connected by a connecting link 10. The link mechanism L is configured such that the upper flap 5a and the lower flap 5b are simultaneously rotated in the same direction (same rotation direction) by the same rotation angle in conjunction with each other.

A rear end of the outer bucket 6 is pivotally supported by the nozzle tube 3, and an intermediate side portion of the outer bucket 6 and a lower lever 7c of the first drive lever 7 are rod-shaped interlocking links. They are pivotally connected to each other via 11.
Therefore, the outer bucket 6 moves up and down in conjunction with the opening and closing operations of the upper and lower flaps 5a and 5b. That is, the interlocking link 11 is interlocked with the first drive lever 7 to move the upper and lower flaps 5a when moving forward (the solid line position in FIG. 1).
When 5b opens the nozzle tube outlet passage 3a, it rises and becomes substantially horizontal, and the lower flap 5b is seated on the lower surface of the nozzle tube 3 to close the opening 4. On the other hand, when the vehicle is moving backward (the position indicated by the phantom line in FIG. 1), the outer bucket 6 is linked with the action of the upper and lower flaps 5a and 5b rotating in the same direction to close the outlet passage 3a through the interlocking link 11 in the imaginary line. Lower to the indicated tilt position. Then, the water jetted from the pump outlet is bent forward through the opening 4 on the lower surface of the nozzle pipe 3 and discharged.

Further, as shown in FIGS. 1 and 2, a bridge 12 is installed between both side walls 6a of the upper portion of the outer bucket 6. The bridge 12 closes the remaining opening area where the lower flap 5b closes the opening 4 at the lower surface opening 4 of the nozzle tube 3 when the outer bucket 6 rises during forward movement (that is, the opening 4 is closed). (The lower flap b and the bridge 12 are closed) to prevent the water jetted from the pump 1 from leaking to the outside unnecessarily, and when the vehicle goes in reverse, it descends together with the outer bucket 6 to ensure a sufficient opening area of the opening 4. Work. Originally, in order to efficiently obtain the backward thrust, it is desirable that the area of the opening 4 be the same as the cross-sectional area of the nozzle tube 3. In this case, it is not preferable to make the length of the lower flap 5b longer than that of the upper flap 5a because the inner flap 5 is divided into two and is configured in a balance type as described later. This is because, if the opening 4 is closed in cooperation with 12, the area of the opening can be sufficiently secured and the reverse thrust can be efficiently generated.

The device of the present invention realizes three useful states of use. That is, as shown in FIG.
(b) Neutral state, (c) Reverse state. Here, the operation of switching from forward movement to neutral movement to reverse movement will be described with time. When moving forward, the working cylinder 8 as shown in (a)
Is shortened, and the upper flap 5 is
a is located parallel to the upper surface of the nozzle tube 3 and has a lower flap 5
b is positioned parallel to the lower surface of the nozzle tube 3, and closes the opening 4 on the lower surface of the nozzle tube 3 with the bridge 12 described above,
Further, the outer bucket 6 is also seated on the lower surface of the nozzle tube 3 so as to accommodate the lower flap 5b. In this state, the outlet passage 3a of the nozzle pipe 3 is opened without any obstruction, and therefore the jet flow from the pump 1 is jetted rearward along the nozzle pipe 3 to generate forward thrust.

From this forward state, when the working cylinder 8 is slightly extended, as shown in (b), the drive levers 7, 9,
The link mechanism L including the connecting link 10 and the like performs a predetermined operation, and in conjunction with this, the upper flap 5a and the lower flap 5
Both b rotate counterclockwise to bring the outlet passage 3a into a half-opened state, and the outer bucket 6 also moves downward by the interlocking link 11 (FIG. 1) to bring the lower surface opening 4 of the nozzle tube 3 into a half-opened state. Thereby, a part of the jet flow from the pump 1 is jetted rearward from the outlet passage 3a,
The other part is bent from the lower surface opening 4 of the nozzle tube 3 to the outer bucket 6 and jets forward, and becomes a neutral state when the forward and backward thrusts match. That is, even if the pump 1 is operating, the ship does not move and the stopped state can be revealed.

When the working cylinder 8 is further extended from this neutral state, as shown in (c), the free ends of the upper flap 5a and the lower flap 5b approach each other, and finally the outlet passage 3a is completely closed. Closed, bottom opening 4 of nozzle tube 3
Will be fully opened. Then, the jet flow from the pump 1 is all bent by the inner flap 5 composed of the upper flap 5a and the lower flap 5b and the outer bucket 6 and jetted forward to generate a backward thrust. The reverse operation may be switched to the forward operation from the reverse operation.

By the way, as shown in FIG. 3, the total water pressure F from the pump is divided by the upper flap 5a and the lower flap 5b by F / 2, and the representative radius r about the axis is the same as in the conventional example (FIG. At R / 2 of 6), the moment per flap acting on the shaft is F · r = F
/ 2 · R / 2 = F · R / 4, and the directions of this moment are opposite to each other. On the other hand, the upper and lower flaps 5
a and 5b are drive levers 7 and 9 forming a link mechanism.
And the connecting links 10 can only rotate in the same rotational direction (for example, from the reverse state of FIG. 3 to the outlet passage 3a).
The upper and lower flaps 5a and 5b are both rotated clockwise when they are opened.

Therefore, the upper and lower flaps 5a, 5b are not
/ Moments are balanced like a balance for every two divisions. That is, the upper flap 5a balances the clockwise moment (+ F · r), and the lower flap 5b balances the counterclockwise moment (−F · r).
This is the reason why it is called the balanced type. When switching this to the forward state, the upper flap 5a is rotated backward and the lower flap 5b is rotated clockwise (clockwise) so that they are horizontal as described above, and the nozzle tube 3 is rotated.
The outlet passage 3a of FIG. 6 is opened, but the force required for this is large enough to break the above-mentioned balance, and it is remarkably quicker than when the total water pressure F (moment F · R) as shown in FIG. 6 is opposed. It can be moved lightly. In addition, L ₁ ,
L ₂ indicates the length of the upper and lower flaps, and is shown in FIGS.
Shows an example where both lengths are equal.

FIG. 4 shows another embodiment. The same components as those in the embodiment of FIG. 1 are designated by the same reference numerals. As shown, it may be the length L ₁ of the upper flap, the opening length L ₂ and unequal. This is when the water jetted from the pump 1 draws a parabola and descends, or the water pressure moment between the upper and lower flaps 5a and 5b is intentionally unbalanced (f ₁ · r ₁ > f ₂ · r ₂ ). And the force (moment:
It is used when balancing with f ₀ · r ₀ ). Therefore, in this case, it is possible to open and close the flap with a smaller actuation force than in the case of the above embodiment. Further, as shown in the drawing, the upper flap 5a and the lower flap 5b may have an angle θ which bulges backward when the outlet passage 3a is closed. This way,
The flow of water when moving backward can be made smoother. Furthermore, instead of switching the forward / backward movement to the working cylinder, link 1 from the hull side
It is also possible to transmit by 3, etc.

By making the lengths of the upper and lower flaps 5a and 5b unequal, and by giving an angle θ bulging when closed, the upper and lower flaps 5a and 5b can be switched when switching between forward and backward.
The rotation angles up to the horizontal position of 5b may have different values. It is necessary for the lower flap 5b to be horizontal along the lower surface of the nozzle tube 3 when the upper and lower flaps 5a, 5b open the outlet passage 3a, but even if the upper flap 5a jumps past horizontal, it does not This is because it does not matter.

[0025]

According to the present invention, since the inner flap is divided into the upper and lower parts so that they are linked in the same direction by one link mechanism, the water pressure acting on the upper and lower flaps is balanced, and the force required to lift the outer bucket is also balanced. Therefore, it is possible to drastically reduce the force required for operation when switching between forward and reverse,
The quickness of the switching operation can be remarkably enhanced by the simple and lightweight device configuration, and as a result, the marine vessel maneuvering performance can be dramatically improved.

In the case where the bridge is provided, when the outer bucket rises during forward movement, the lower flap closes the remaining opening area that closes this opening at the opening on the lower surface of the nozzle tube, and the injection from the pump is performed. It is possible to secure a sufficient opening area of the opening by preventing water from leaking unnecessarily to the lower part and descending together with the outer bucket during reverse travel to shorten the length L ₂ of the lower flap as necessary. .. As a result, it is possible to efficiently obtain the reverse thrust.

[Brief description of drawings]

FIG. 1 is a side view of a main part according to a first embodiment of a device of the present invention, in which a solid line position of a link mechanism and the like indicates a forward traveling state and a virtual line position indicates a backward traveling state.

2 (a), (b) and (c) are partial side sectional views in FIG. 1, in which (a) shows a forward state, (b) shows a neutral state, and (c) shows a backward state.

FIG. 3 is an action diagram of the fluid force in the backward movement state of the device of the present invention.

FIG. 4 is a side sectional view according to a second embodiment of the device of the present invention.

FIG. 5 is a side sectional view of a reverse device according to a conventional example.

FIG. 6 is an action diagram of fluid force in the case of the conventional example.

[Explanation of symbols]

 H ... Hull 1 ... Pump 2 ... Outlet 3 ... Nozzle tube 4 ... Opening 5 ... Inner flap 5a ... Upper flap 5b ... Lower flap 6 ... Outer flap 7 ... First drive lever 8 ... Working cylinder 9 ... Second drive lever 10 ... Connection link 11 ... Interlocking link 12 ... Bridge L ... Link mechanism

Claims (2)

[Claims] 1. An inner flap and an outer side, each of which is provided with an opening on the lower surface of a nozzle pipe connected to a pump and having an outlet passage opened at the rear of the ship, and which is arranged so as to close the opening from the inside and the outside of the nozzle pipe, respectively. In a water jet propulsion device having a bucket, the inner flap is divided into upper and lower two parts to form an upper flap and a lower flap, and one end of the upper flap is pivotally supported on an upper portion of a nozzle pipe, and the lower portion is One end of the flap is pivotally supported on the lower part of the nozzle tube, and two upper and lower flaps are connected to a link mechanism to rotate in the same direction at the same time. A reverse device for a water jet propulsion device, wherein the outlet passage is opened and closed. 2. A bridge is installed on the upper portions of both side walls of the outer bucket, and when the outer bucket rises during forward movement, the bridge and the lower flap close the opening on the lower surface of the nozzle tube. The reverse device of the water injection propulsion device according to Item 1.