JPS5842074B2 - Senpakuyoufunriyugatasuishinouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a rectifier plate on the downstream side of a jet pump installed in a jet water duct, and a boss formed in the center of the rectifier plate allows the pump blade side end of the jet pump to be controlled by a boss formed in the center of the rectifier plate. The present invention relates to a jet propulsion device for ships that is supported.

Vessels (eg motorboats) using this type of jet propulsion device have a promising future in terms of safety and shallow sea navigation.

However, if a conventional ship incorporating the above-mentioned jet propulsion device is used as is in Japanese waters where seawater pollution is more advanced than in other countries, various problems will occur.

In other words, (a) elongated foreign objects such as synthetic fiber wrapping strings and scraps floating on the water surface may wrap around the bearing and destroy it, and (b) seaweed such as tengusa, solder straw, or vinyl chloride. Problems arise, such as small foreign objects such as cut ends of polymer films such as those that clog the rectifying plate and impair its rectifying function.

SUMMARY OF THE INVENTION An object of the present invention is to provide a new jet propulsion device for ships that solves the above problems.

The structure of the invention and its advantages will now be explained in relation to the prior art with reference to the accompanying drawings.

In FIG. 1, numeral 10 is a hull wall forming the rear surface of the ship, and 10' is a hull wall forming the bottom surface of the ship.

A jet water duct 12 is fixed to the rear part of the bottom formed by these hull walls 10 and 10', in which a circular passage 13 is defined.

As shown, this passage 13 is curved above the bottom wall 10/.

A jet pump 14 is installed inside the jet water duct 12.

The pump 14 includes a rotating shaft 16 and a pump vane 18 attached to the rear end of the rotating shaft 16.

The front portion of the rotating shaft 16 is rotatably supported by the wall of the duct 12, and a joining flange portion 20 for connecting to a prime mover (not shown) is fixed to the front end of the shaft 16.

The pump vane 18 has several vanes and is located within the outlet end of the passage 13 within the duct 12 as shown.

A rectifying water duct 22 is fixedly arranged downstream of the jet water duct 12.

One (or several) rectifying plate 26 is fixedly disposed across the center of a circular passage 24 formed within the rectifying water duct 22.

As shown in the figure, the front edge of the current plate 26 directly faces the propeller blade 18.

A substantially conical boss portion 28 is formed in the center of the current plate 26, and the boss portion 30 of the propeller blade 18 (ie, the rear end of the rotating shaft 16) is supported by the boss portion 28.

A filter plate 3 is installed at the entrance of the passage 13 in the jet water duct 12.
2 is fixed to prevent large foreign matter floating in the water, such as a polymer film, from being sucked into the passage 13.

Note that a rudder mechanism is provided downstream of the rectified water duct 22 to control the direction of the rectified jet flow from the duct and adjust the traveling direction of the ship to the left, right, or rearward. Not shown.

As is clear from FIG. 2, which shows the pump blade 18 and the rectifying plate 26 in detail in FIG. A bottom annular flange 28' of the conical boss portion 28 of the baffle plate 26 is accommodated, and this flange 2
8' center hole and the center protrusion 34 in the annular recess 34.
A seal and a bearing 36 are arranged between the propeller blade 18 and the rear end of the shaft 16 so as to rotatably support the propeller blade 18 or the rear end of the shaft 16.

Therefore, the boss portion 30 of the pump blade 18 and the rectifying plate 26
The parting line l formed by the boss portion 28 of the pump blade is located on a plane substantially perpendicular to the rotation axis L-L of the pump blade,
As a result, the gap S between these boss portions 30 and 28 opens horizontally rearward.

Furthermore, the front edge 26 of the current plate 26 facing the pump blade 18
' is inclined rearward with respect to the rotational axis LL,
Therefore, the rear surface of the propeller blade 18 and the front edge 26 of the current plate
A substantially triangular space Q is left between / and the surface of the tapered boss portion 28.

The operation of the jet propulsion device for ships according to the present invention described above will be explained.

When power is applied to the pump 14 from a prime mover (not shown) via the flange portion 20, the pump blades 18 rotate.

Due to this rotation □ of the pump blade 18, water below the bottom 10' of the ship is sucked into the passage 13 through the filter 32 as shown by arrow A, and is ejected from the rear surface of the propeller blade 18 in the form of a whirlpool.

This ejected vortex is rectified by the rectifying plate 26 and ejected from the rear of the passage 24 as shown by arrow B, and the reaction force at this time causes the ship to proceed.

The direction of travel of the ship is adjusted by a rudder located downstream of the duct 22.

When water is sucked into the duct 12 by the rotation of the propeller blades 18, large floating foreign objects are blocked by the filter 32, but elongated foreign objects such as the edges of synthetic fiber wrappings and straw, or seaweed such as tengusa and solder straw. , or small foreign objects such as cut ends of polymeric films are sucked through the filter 32 .

However, in the device of the present invention, these floating objects do not wrap around the bearing 36 and destroy it.

This is because, as explained with reference to FIG. 2, in the present invention, the parting line l between the boss portion 30 of the propeller blade 18 and the center boss portion 28 of the current plate 26 is a plane that is substantially orthogonal to the rotation axis LL. This is because it is located at the top.

In other words, the gap S between the boss portion 30 of the propeller blade 18 and the flange portion 28/ of the center boss portion 28 of the current plate 26 faces horizontally backward, and the propeller blade 18
This is because it is difficult for floating foreign matter ejected from the bearing 36 to pass through the gap S and enter the bearing 36.

These advantages of the present invention will become more apparent with reference to the conventional jet propulsion device shown in FIG.

That is, in the conventional device, the parting line 1/ formed by the central gas part 128 of the baffle plate 126 and the central boss part 130 of the propeller blade 118 is approximately parallel to the rotational axis I, /I, / of the propeller blade 118. The boss portion 130 of the propeller blade 118 and the baffle plate 1 are in a plane.
26 and the center boss portion 128 of the
is oriented in the vertical direction, and as a result, floating objects (especially synthetic fiber strings, strings, etc.) ejected from the propeller blades 118 easily enter the gap S/, and therefore, they wrap around the bearing 136 and cause the bearing 136 Accidents in which the equipment was destroyed were likely to occur.

In addition to the above-described advantage that floating foreign matter is difficult to enter into the bearing 36, the jet propulsion device of the present invention does not have the problem that floating matter blocks the rectifying plate and deteriorating the rectifying function.

This is because in the present invention, the boss portion 28 of the current plate 26
is tapered, and the front edge 26/ of the rectifying plate 26 facing the pump blade 26 is inclined rearward with respect to the rotation axis LL, and a triangular space Q is formed at the base of the joint between the boss 28 and the rectifying plate 26. is formed, and as a result, floating objects ejected from the pump blade 18 (particularly small foreign objects such as seaweed such as amberjack and solder straw, and the cut ends of polymeric films such as vinyl chloride) are focused in the space Q. It is from.

The region Q in the figure is relatively close to the rotational axis L-Ll of the propeller blade 18, so even if floating foreign matter accumulates in the region Q, the effect on the rectification effect is small and there is no problem.

Furthermore, since the floating foreign matter is concentrated and accumulated in the region Q, its removal can be performed quickly and easily.

However, in the conventional jet propulsion device shown in FIG.
tended to converge in region R at the leading edge of.

This region R is the rotation axis I of the propeller blade 118, /
If floating matter were to accumulate in the region H, which is far from I,/, the rectifying effect of the rectifying plate 126 would be extremely adversely affected.

As explained above, according to the present invention, it is possible to prevent floating foreign objects in the water from entering the bearings of the propeller blades, and there is also an effect that floating objects do not block the rectifying plate and worsening its rectifying effect. play.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a jet propulsion device for ships according to the present invention. FIG. 2 is a partially enlarged view of the propeller blade and current plate in FIG. 1. FIG. 3 is a partial diagram showing an example of the conventional structure of the same part as FIG. 2. 12... Jet water duct, 14... Jet pump, 18...
...Pump vane, 22... Rectifying water duct, 26...
Current plate, 28... Boss portion of current plate, 30... Boss portion of pump blade, 36... Bearing, L-L... Rotation axis, l... Parting line.

Claims (1)

[Claims] 1 Jet type propulsion for ships, in which a rectifying plate is provided on the downstream side of a jet pump installed in a jet water duct, and a boss portion formed in the center of the rectifying plate supports the pump blade side end of the jet pump. In the device; the parting line formed by the boss portion of the pump blade and the straightening plate boss portion is approximately perpendicular to the rotation axis of the pump blade so that the gap formed between them is opened horizontally backward. A jet propulsion device for a ship, wherein the front edge of the baffle plate facing the pump blade is tilted rearward toward the rotation axis.