JPS6158357B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waterjet propulsion device used in a small boat, and particularly to a protection structure for a stator blade thereof.

This type of waterjet propulsion device sucks water through a suction port opened on the bottom of the ship, accelerates this water with an impeller installed in the duct, and jets it strongly backwards, obtaining propulsive force from the reaction force. It is something.

By the way, when sailing in shallow water, pebbles, gravel, wood chips, and other solid substances are often mixed into the water sucked in, and these solid substances are absorbed by the impeller and the rectifying vanes installed behind it. also collides. Since the impeller rotates along with the water flow and is made of a relatively rigid material, the rate of damage is low. Since it is fixed in the water stream, solid objects are likely to collide with the front end edge on the impeller side, in particular.

Therefore, considering the fact that the duct members are often cast from aluminum alloy, the front edge of the stationary blade is often deformed or damaged by the collision, resulting in a problem of reduced performance. Ta.
Furthermore, if the stator vanes are deformed or damaged in this way, it is not enough to simply replace the stator vanes, but also the relatively large duct components, which requires extensive work and costs. There were also problems such as increased volume.

This invention was made based on the above circumstances, and it is possible to reliably prevent damage to the stationary blades, maintain good rectification performance over a long period of time, and, if the protective member is damaged, It is an object of the present invention to provide a waterjet propulsion device for a ship which can save costs by requiring only this protective member to be replaced and by allowing the duct parts integrated with the stationary vanes to be used repeatedly as they are.

That is, in order to achieve the above object, the present invention is characterized in that a protective member is removably attached to the front end edge of the stationary blade that is integral with the duct member.

An embodiment of the present invention will be described below based on the drawings. .

In the figure, numeral 1 indicates the hull, which is made of, for example, FRP (fiber-reinforced plastic). The hull 1 has a recess 4 extending from the bottom surface 2 to the transom 3.
is formed, and a suction duct member 5 made of aluminum alloy or the like is attached to this recess 4. This suction duct member 5 constitutes a suction duct 6, and constitutes a suction port 7 flush with the bottom surface 2 of the ship. Note that the suction port 7 is provided with a grid 8 for capturing bulky waste. A bearing chamber 9 is formed in the recess 4 of the hull 1 and is recessed toward the inside of the ship. A bearing case 10 formed integrally with the suction duct member 5 is fitted into the bearing chamber 9 in a fluid-tight manner. A bearing and an oil seal (none of which are shown) are installed in the bearing case 10, and support the drive shaft 11 in a fluid-tight manner. One end of the drive shaft 11 is introduced into the ship and connected to an engine (not shown). The other end of the drive shaft 11 is inserted through the suction duct 6 and guided into an impeller duct which will be described later. Note that an inspection hole 12 is opened in the suction duct member 5, and this inspection hole 12 communicates with an inspection cylinder 13 provided inside the hull 1. An inspection lid 14 is attached to the upper opening of the inspection cylinder 13 so as to be openable and closable.

An impeller duct member 15 made of aluminum alloy or the like is connected to the rear end of the suction duct member 5, and an impeller duct 16 communicating with the suction duct 6 is formed within the impeller duct member 15. The impeller duct member 15 has a fixed flange 17 at the front end, and this fixed flange 1
7 is removably fixed to the transom 3 by bolts 18 and nuts 19. Stator blades 20 are integrally provided within the impeller duct 16 at intervals in the circumferential direction. Further, a bearing case 21 is integrally provided at the center of the stationary blades 20. Inside this bearing case 21 is a bearing 2.
2 and an oil seal 23 are housed therein, and pivotally support the rear end of the drive shaft 11. An impeller 24 is attached to the drive shaft 11 in close proximity to the front of the stationary blades 20 so as to rotate together with the stator blades 20. An auxiliary cylinder 25 is arranged around the impeller 24 so as to cover the inner surface of the impeller duct member 15. This auxiliary cylinder body 25 is integrally fixed to the rear end of the suction duct member 5. The impeller duct member 15 has a stepped portion 26 facing the rear end surface of the auxiliary cylinder 25, and the protective member 2 according to the present invention is provided between the auxiliary cylinder 25 and the stepped portion 26.
It is holding 7. The protective member 27 has an outer flange 28 and an inner flange 29 as shown in FIG.
Rib portions 30 facing the stationary blades 20, respectively.
…have. These rib portions 30... have stationary blades 2
The protective cap 31 is integrally provided with a protective cap 31 that is removably fitted onto the front edge of the 0. Note that such a protection member 27 is made of stator blade 20 made of cold rolled steel or the like.
It is made of a material that is more rigid than... The outer flange 28 is sandwiched between the rear end surface of the auxiliary cylinder 25 and the step portion 26 of the impeller duct member 15, and the inner flange 29 is sandwiched between the boss portion 24a of the impeller 24 and the bearing case 21. has been done. Note that 32 indicates a rear end cap of the bearing case 21.

Further, a steering nozzle 34 is connected to the rear end of the impeller duct member 15 via support shafts 33a and 33b attached vertically to the steering nozzle 34, which is swingable in left and right horizontal directions. This steering nozzle 34 has an operating lever 35.
are connected, and this control lever 35 can be accessed from inside the ship.
By operating the direction of the steering nozzle 34, the traveling direction of the hull 1 is controlled. Further, on the side of this steering nozzle 34, there are reverse injection nozzles 36, 36 facing diagonally forward of the hull 1.
(only one of which is shown) is formed. At the rear end opening of the steering nozzle 34, a forward/reverse switching cover 37 is rotatably opened/closed about a support shaft 38. This forward/reverse switching cover 37 is operated by an operating rod 39,
If the rear end opening of the steering nozzle 34 is closed, the direction of the water jetted rearward through the steering nozzle 34 is changed to the front, and the water is diverted forward.
6 and towards the front.
As a result, the hull 1 can be moved backward. Note that 40 is an auxiliary steering plate, which is fixed to the steering nozzle 34 via a mounting bracket 41 and bolts 42 .

In the waterjet propulsion device having such a configuration, when the drive shaft 11 is rotated by the engine, the impeller 24 rotates together. This impeller 24 sucks water from the suction port 7 opened on the bottom surface 2 of the ship, and this water is accelerated by the impeller 24 and becomes a jet stream and flows rearward within the impeller duct 16. This jet flow is rectified by the stationary blades 20 and then sent to the steering nozzle 34.
The liquid is ejected from the rear end opening of No. 4 along the opening direction. Therefore, since the reaction force of the jet is applied to the hull 1, this reaction force becomes a propulsive force and the ship moves forward. The direction of movement of the hull 1 can be changed by operating the direction of the steering nozzle 34, and by adjusting the opening of the steering nozzle 34 with the forward/reverse switching cover 37, the forward speed can be changed. Allows change, neutrality and reversing.

By the way, when sailing in shallow water, etc., the suction port 7
Solid objects such as pebbles, gravel, and wood chips are likely to be sucked in together with the water, and this may be accelerated by the impeller 24 and collide with the stationary blades 20.

However, in the above configuration, the front edges of the stator blades 20 are covered with the protective caps 31 of the protection member 27, so solid objects do not directly hit the stator blades 20. Since the protective member 27 is made of a plate material having higher rigidity than the stationary blades 20..., the protective member 27
There is little damage or wear to the stationary blades 20, and deformation or breakage of the stationary blades 20 can be reliably prevented.

Furthermore, since the surfaces of the stationary blades 20 are less likely to be scratched, corrosion is less likely to occur.

Furthermore, if the protective member 27 itself that protects the stationary blades 20 is significantly damaged or worn, it is sufficient to replace only the protective member 27. That is, in order to replace the protection member 27, the rear end cap 32 of the bearing case 21 inside the impeller duct member 15 is removed, and the connection between the bearing case 21 and the drive shaft 11 is released. At the same time, the fixing flange 17 of the impeller duct member 15 is removed from the transom 3 by removing the bolts 18, nuts 19, and so on. When the impeller duct member 15 is pulled apart rearward in this state, the steering nozzle 34 and the forward/reverse switching cover 37 are integrally attached to the impeller duct member 15, that is, the impeller duct member remains in a unit state. 15 comes off from the hull 1. In this case, the protection member 27 is separated from the support cylinder 25 attached to the impeller duct member 15 and the impeller boss portion 24a. Therefore, if the protection member 27 is pulled out in front of the impeller duct member 15 while the impeller duct member 15 is sufficiently separated from the suction duct member 5, the protection member 27 will be removed. Therefore, the new protective member 27 is replaced with a new protective member 27, and the new protective member 27 is attached to the front end of the impeller duct member 15, particularly by fitting the protective caps 31 of the protective member 27 onto the front edges of the stationary blades 20. Thereafter, the impeller duct member 15 is again fixed to the transom 3 via its fixing flange 17.
In this way, the protection member 27 has an outer flange 28 that is connected to the auxiliary cylinder body 25 and the impeller duct member 1.
Since the inner flange 29 is held between the impeller boss part 24a and the bearing case 21, it is firmly fixed.

Therefore, such a protective member 27 can be easily replaced, and is extremely firmly fixed in the installed state. Since such a protection member 27 is a small component compared to the stator vanes 20 formed integrally with the impeller duct member 15, the cost for replacing it can be reduced.

Note that the protection member 27 is not limited to being made of a metal member with high rigidity, and may be made of rubber or synthetic resin material, for example.

According to the invention described in detail above, the protective member is removably attached to the front edge of the stator blade, so that solid objects such as pebbles, gravel, and wood chips that are accelerated toward the stator blade are not received by the protective member. This prevents this solid material from directly colliding with the stationary blades. Therefore, deformation and damage to the stator vanes can be reliably prevented, and good rectification performance can be maintained over a long period of time. Moreover, if the protective member is damaged due to long-term use, it is only necessary to replace this protective member with a new one, and the duct member integrated with the stator vane can be used repeatedly as is, and the protective member is Since it is a small part compared to other members, there is no need for large-scale work when replacing it, which has the advantage of being able to save costs and being able to replace it at a low cost.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which FIG. 1 is a sectional view of the rear bottom of the hull, FIG. 2 is a front view of the protective member, FIG. 3 is a sectional view taken along the line - in FIG. The figure is a sectional view taken along the line -- in FIG. 1...Hull, 2...Bottom surface, 3...Transom, 5...Suction duct member, 6...Suction duct,
15... Impeller duct member, 16... Impeller duct, 17... Fixed flange, 20... Stationary blade,
24... Impeller, 27... Protective member, 31...
protective cap.

Claims (1)

[Scope of Claims] 1 Water sucked in from the suction port is accelerated by an impeller, and this water is guided backward through a duct member, and stator vanes are integrated on the inner surface of this duct member to rectify the accelerated water. 1. A waterjet propulsion device for a ship, characterized in that a protective member is removably attached to the front edge of the stationary blade facing the impeller.