JPH02164657A - Fan duct for small size hovercraft - Google Patents

Abstract

PURPOSE:To simply and exactly divide the air sent from a fan into a propelling air and an air for buoyance by providing partition plates so that the partion plates form a sector by a central point and an outer peripheral circular arc surface of a fan duct. CONSTITUTION:With an air current sent by a fan 2 installed in a fan duct 1, a part of the air current is introduced as a propelling air current (A) into the rear of a hull 3, and the remaining air is introduced as an air current (B) for buoyance into a skirt 5 by means of partition plates 4. In this case, for the partion plates 4, two plates are installed in the axis direction of the fan so that the plates form a sector by a central point and an outer peripheral circular arc surface, and extended from the central direction of the fan 2 to the fan duct 1 and fixed at the leeward direction. A ratio of the air volume for buoyancy to the whole blasted air volume of the fan 2 can thus be exactly set.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fan duct for a small hovercraft.

(Prior technology) In a conventional engine-based hovercraft that performs both levitation and propulsion, a partition plate installed horizontally in an upright fan duct is used to use a percentage of the air flow for levitation. It is generally known that the efficiency of fan blades is not uniform from the center to the tip, which is why a partition plate is placed horizontally in the conventional fan duct! With the two-position model, even if it was decided to use a percentage of the air flow for levitation, it was very difficult to set the mounting position.

(Problem M to be Solved by the Invention) The present invention solves these problems of the prior art, and makes it possible to easily take out the air flow of the ratio determined to be used for flotation from the air flow in the fan duct. This is what I did.

(Means for Solving Problems) That is, the present invention provides a fan-shaped projection plane II (levitation This was carried out based on the idea that two air flows for propulsion and levitation are separated from one fan, and two fans are installed in the axial direction in a hovercraft fan duct 1. The structure of a fan duct for a small hovercraft is characterized in that a partition plate is provided that extends from the center of the fan toward the fan duct and connects the leeward direction, and the air flow separated by the partition plate is used for levitation. This is a summary.

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

Fig. 1 is a y4WJ diagram of a hovercraft in which the present invention is implemented, and the airflow generated by the fan 2 installed in the fan duct 1 is partially behind the hull 3 as a propulsion airflow as shown by arrow A. Then, a part of the air is guided into the skirt 5 as a floating air flow by the partition plate 4 as shown by arrow B.

FIG. 2 is an enlarged perspective view of the main part of the present invention, showing the state of the partition plate 4. A part of the air flow generated by the fan 2 is directed by the partition plate 4 provided on the left and right sides and connected on the leeward side. As shown in B, it is taken downward and used for levitation.

FIG. 3 is an enlarged front view of the main part of a conventional fan duct. A partition plate 4 is installed tangentially to the fan duct 1, and is separated into a propulsion duct A and a floating duct B.

Figure 4 is an enlarged front view of the main parts of the present invention, showing the fan duct 1.
On the other hand, the partition plate 4 is installed in a fan shape and is separated into a propulsion duct 8 and a floating duct B.

Fig. 5 is an enlarged front view of the main part showing the embodiment of the pond of the present invention, and is provided above the partition plate 4 which is shaded 12r11, and the partition plate 4 also plays the role of stator vane. By having this, the amount of air blown to the propulsion duct can be made uniform on the left and right sides. This is very effective when a reversing device is installed behind the fan duct. Further, it is also possible to provide one end of the rotation shaft of the fan 2 on the upper part of the partition plate 4 of the present invention.

Further, in the embodiments, all fan ducts are installed vertically, but it goes without saying that fan ducts installed horizontally are also effective.

(Effects of the Invention) Since the present invention is configured as described above, it produces effects as described below.

It is possible to accurately set the ratio of the amount of air for floating to the total amount of air blown by the fan.

Furthermore, by changing the angle of the partition plate without changing the position of the fan duct, the ratio of the amount of air for floating can be changed.

Furthermore, the partition plate can be used as a stationary blade.

Also, by inserting stator blades or beams above it, it can be used as a reinforcement material for fan ducts.

Furthermore, the mounting of the rotation shaft of the fan can also be used as a part.

[Brief explanation of the drawing]

FIG. 1 is an open view of a hovercraft embodying the present invention. FIG. 2 is an enlarged perspective view of the main part of the conventional fan duct, and FIG. 3 is an enlarged front view of the main part of the conventional fan duct. FIG. 4 is an enlarged front view of the essential parts of a fan duct according to the present invention, and FIG. 5 is an enlarged front view of the essential parts of a fan duct according to another embodiment. The symbols in the figure are explained as follows.

Claims (1)

[Claims] In the fan duct of a small hovercraft, which separates two air flows for propulsion and levitation from one fan, two pieces draw a fan shape formed by the center point of the fan duct and the arc of the fan duct. A fan duct for a small hovercraft characterized by having a partition plate installed in the fan axis direction, extending from the center direction of the fan to the fan duct direction, and connecting the leeward direction, and using the air flow separated by the partition plate for levitation.