JPS5853596A - Light buoy - Google Patents

Abstract

PURPOSE:To secure the stable stationary condition of a light buoy in a water flow, by a method wherein the direction of a shorter resistance plate is set to coincide with the fitting direction of a mooring piece, in the light buoy provided with longer and shorter resistance plates in a crossed configuration at the lower end part of a column or body. CONSTITUTION:A light buoy is provided with a lighting fixture 2 at the upper end of the columnar body 1, the longer and shorter resistance plates 3 in a crossed configuration at the lower end part of the body 1, a float body 4 at an intermediate part of the body 1, and the mooring piece 5 fitted to the body 1 at an intermediate position between the float body 4 and the resistance plates 3. The mooring piece 5 moored to an anchor resting at the seabed by a mooring cable 6, and the fitting direction of the piece 5 is set to coincide with the direction of the shorter resistance plate 7. Accordingly, under the function of the longer and shorter resistance plates 3, the direction of the shorter resistance plate 7 coincides with the direction of water flow to stabilize the buoy. Namely, the shorter resistance plate 7 is directed in the direction of the water flow to function as a vibration-preventing resistance plate, while the longer resistance plate 8 is directed orthogonally to the direction of the water flow to perform a stabilizing action by resisting to the water flow.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a floating light buoy with a cross-shaped resistance plate suitable for fast-flowing straits and rivers.

As a conventional floating light buoy equipped with long and short cross-shaped resistance plates,
A light buoy as shown in Japanese Patent Publication No. 42-9616 was used.

This conventional light buoy has a pair of blades (resistance plates) arranged in a cross shape at the lower end of the cylinder (column), one blade is longer than the other, and the shorter blade is is placed perpendicular to the tidal flow as a tidal current resistance plate, and the longer blade is placed in the direction of the tidal current as a directional plate. That is,
The mooring piece is attached so that it is in the same direction as the direction vane.

By doing this, it was possible to always stay upright and maintain direction even in areas with rapid currents.

However, in actual use, this conventional light buoy had good uprightness, but its directionality was subject to rotation due to tidal currents. There have been cases where the mooring parts and mooring parts have been worn out and damaged.

In order to elucidate the cause of this, a floating light buoy with such long and short cross-shaped resistance plates rotates in relation to the tidal current, and under what conditions does the cross-shaped resistance plate rotate? :
12. . 20.2 A column with a cross-shaped resistance plate at the bottom is held in the water flow so that it can rotate in one direction (see Figure 4), and the length of the short side a and the long side The rotation situation in each case was investigated by changing the relationship between the two.

As a result, when b) and a are given lengths and degrees, as shown in Figure 3, if b) a is less than /a = 2.0, then
As shown in Figure 2 (b), the light buoy rotates left and right at a maximum rotation angle of 30 degrees with its short side in the water flow direction, and its swing decreases as /a increases, and b/, L=
2.0, that is, when the short side a is 1/2 the length of the long side, the direction of the short side a is on the same direction as the water flow ÷ it is stable with a slight swing of 2 degrees to the left and right, and b/ , = 2.5, it was found that the short side a stands still in the same direction as the water flow, and almost no rotation is observed.

However, if the short side a is close to 0 and /a=3 or more,
The influence of the Karman vortex generated in the column overcomes the vibration resistance of the resistance plate (vibration prevention resistance plate) on the short side a, allowing it to swing left and right.

In other words, in the range of b/a = 2.0 to 3.0, the short side is stable and coincides with the water flow direction, and the long side is stable in the water flow direction, completely opposite to the conventional case where the long side is aligned with the water flow direction. Acts as a right-angled water flow resistance plate.

The present invention is based on the characteristics of a light buoy having long and short cross-shaped resistance plates with respect to water flow, and the mooring piece is installed in the same direction as the short side resistance plates, so that the short side resistance plates are free from lateral deflection ( In other words, the long side resistance plate is a water flow resistance plate perpendicular to the water flow, and the length of the long side water flow resistance plate is equal to the short side vibration. This prevents the light buoy from rotating even in water flow, and prevents accidents such as entanglement of mooring lines and wear and tear of mooring parts. few,
Moreover, it is possible to provide an economical light buoy with stable orientation and good uprightness.

The contents will be described in detail below according to the embodiments shown in the accompanying drawings.

FIG. 1(A) is a front view of the external appearance of a light buoy according to the present invention, and FIG. 1(B) is a side view of its essential parts.

In addition, Figures 2 (a) and (b) are a plan view of the cross-shaped resistance plate and an explanatory diagram of its operation, and Figure 3 is a diagram of the light buoy with respect to the length ratio of the long side and short side of the cross-shaped resistance plate. It is a characteristic diagram of a Takako experiment showing the relationship between rotation angles.

As shown in the figure, the light buoy of the present invention has a lamp (2) at the upper end of a column (1), and a long and short cross-shaped resistance plate (3) at the lower end.
It has a structure in which a buoyant body (4) is provided in the middle, and the buoyant body (4) and the mooring piece (5) are moored to a sinker (not shown) on the seabed by a mooring line (6). consists of things. (On the upper side, there is a buoyant body (4) that supports the lamp (2)
The upper column (1) may be shaped like a turret, and the turret-shaped body may support am<2). As shown in a), it is composed of a vibration prevention resistance plate (7) on the short side and a water flow resistance plate (8) on the long side. (The arrow indicates the direction of water flow.) In the present invention, the attachment direction of the mooring piece (5) is the same as the direction of the resistance plate (7) on the short side (see Fig. 1 (b)). Due to the action of the long and short resistance plates, the light buoy stands still stably with its short side aligned with the water flow direction.

Furthermore, the arm length of the mooring piece (5) is 0 and the restoring moment of the water flow resistance of the light buoy makes it even more stable.

That is, when the light buoy is installed by the mooring line (6), the resistance plate (7) on the short side matches the direction of the water flow and acts as an anti-vibration resistance plate, and the resistance plate (8) on the long side acts as a vibration prevention resistance plate in line with the direction of the water flow. It acts stably as a water flow resistance plate perpendicular to the current, and the light buoy stands stably upright without wobbling or rotating even in rapid water.

In addition, light buoys installed in this way are prevented from vibrating and rotating without vibration even during rapid currents in rivers, straits, etc., preventing damage caused by entanglement of the mooring line and column, and excessive wear on the mooring fittings. becomes.

Therefore, there is no accident of the light buoy being spilled out for a longer period of time than before.
able to perform its functions.

In addition, when this type of light buoy rotates, the water flow resistance of the water flow resistance plate changes, which causes a tilting of the front, back, left, and right, resulting in a complicated oscillation and rotation movement, and the light of the light buoy changes in the distance. This results in loss of sexuality. Therefore, rotation must be absolutely avoided, and the present invention completely solves this problem.

In addition, the resistance plate that generates resistance to stand upright in the water flow is the long side resistance plate (8) (conventionally the short side), and the vibration prevention resistance plate in the water flow direction is the short side resistance plate (7) ( Conventionally, the long side)
As a result, the resistance plate in the water flow direction is smaller than before, and it is also superior from an economical point of view. Therefore, it can be made compact as a whole and is convenient to handle.

As described above, the light buoy according to the present invention is suitable for places where there is constant flow, such as in straits or canals, and where the direction of the flow changes with time. Since there is no rotational movement and the mooring line has good uprightness, there is no chance of the mooring cable getting entangled with the column or cross-shaped resistance plate.
Therefore, in addition to reducing wear and tear accidents, the wear and tear of the mooring portion due to friction is also greatly reduced, making it possible to provide an economical light buoy with a long life.

[Brief explanation of drawings]

Figure 1 (A) is an external front view of the light buoy according to the present invention, Figure 1 (B) is a side view of the main part of Figure 1 (A), and Figure 2 (A).
is a cross-sectional view of the harbor in Figure 1 (b), Figure 2 (b) is an explanatory diagram of the operation of the cross-shaped resistance plate, Figure 3 is a rotation frame and sexual diagram of the cross-shaped resistance plate, and Figure 4 (a) and (b) are a front view and a plan view schematically showing an experimental apparatus in which a column having long and short cross-shaped resistance plates is held in water so as to be freely rotatable. Body, (5), Mooring piece, (6), Mooring rope, (7)
, , Anti-vibration resistance plate, (8), , Water flow resistance plate. Patent Applicant Take Yasu Ino 3 1 Sex (6) Collection 1 Concave (A) Figure 2 Figure 3 111 Bar Figure 4 (A) (B)

Claims (1)

[Claims] 1. A lamp is provided at the upper end of the column, a long and short cross-shaped resistance plate is provided at the lower end, a buoyant body is provided in the middle, and a mooring piece is provided on the column between the buoyant body and the resistance plate. In a floating light buoy in which the mooring piece is moored to the sinker, the direction in which the mooring piece is installed is in the direction of the vibration prevention resistance plate on the short side in the water flow direction, and the resistance plate on the long side is perpendicular to the water flow. A light buoy characterized by a water flow resistance plate. 2. The light buoy according to claim 1, wherein the length of the water flow resistance plate on the long side is not less than 2 times and not more than 3 times the length of the vibration prevention resistance plate on the short side.