JPH0226984Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a pollution diffusion prevention curtain that prevents the dispersion of earth and sand and sludge in water during dredging and the like.

(Prior Art) The most common pollution prevention curtain used in the past is a curtain-like body 3 equipped with a weight 2 such as a ballast chain at the lower end of a main float 1, as shown in FIG. In addition to hanging down to an appropriate depth, main ropes 4, 4 are stretched in an inverted V shape to the seabed on the left and right sides of this curtain-like body, and the lower ends of the main ropes are fixed to anchors 5, 5.

However, in the case of this structure, when the water level drops due to the ebb and flow of the tide as shown in FIG. 5, the main rope on the upstream side is stretched, while the main rope on the downstream side becomes slack. The central curtain body 3 is swung downstream by the tide, and the ballast chain, which is the weight at its lower end, comes into contact with the slackened main rope. If this condition is repeated for a long time, even if the main rope is made of wire rope, the wire rope may be damaged due to contact with the ballast chain or impact.

In order to prevent this phenomenon, a method is adopted in which a sub-anchor 8 is provided at the bottom of the curtain-like body 3 and connected to the weight 2 by a sub-rope 9 to limit the swinging of the curtain-like body 3, as shown in FIG. However, since the pressure applied to the curtain increases, each member has to be made larger overall, and it takes time and effort to install, so it is not used much these days.

In addition, there is a device equipped with a sub-float in Japanese Utility Model Application Publication No. 49-47437,
The secondary float in this case is designed to prevent the main float from being pulled down below the water surface due to the accumulation of dredged sludge, etc., and is provided with some space between it and the main float. This invention is different from the invention of the present application in terms of purpose, structure, and effect. Furthermore, in the floating type oil fence disclosed in Japanese Utility Model Publication No. 51-63630, there is a description of a oil fence with separate floats on the left and right sides of the oil fence body equipped with a float tube. The height position of the fence body is changed by filling and unloading, and the fence body and the float are simply connected by a rope, and when the floats on both sides are submerged, If the weight at the lower end of the fence body swings from side to side, it will come into contact with the float or connector and cause damage.

(Problem to be solved by the invention) The present invention relates to a pollution diffusion prevention curtain that does not have a conventional sub-anchor. This prevents the rope from coming into contact with the main rope 4.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a number of sub-floats above the main rope on the downstream side, which would normally slacken when the water level drops. The main rope is floated to eliminate slack, and even if the weight swings, it does not come into contact with the main rope.An example of this will be described below with reference to the drawings.

(Structure of the invention) Fig. 1 shows a typical example of the invention, in which a curtain-like body 3 having a weight 2 at the lower end by a ballast chain or the like is provided in a hanging manner at the lower part of the main float 1. In the conventional pollution diffusion prevention curtain, wire main ropes 4, 4 are stretched in an inverted V shape on the left and right sides of the body, and the lower ends of the main ropes are fixed to anchors 5, 5 installed on the seabed. A plurality of sub-floats 6 are provided over a range slightly longer than the length of the curtain-like body 3 from the vicinity of the connecting portion of the main ropes 4, 4 with the main float 1.

Various kinds of sub-floats 6 can be used as the sub-float 6 used here, and this sub-float may be inserted through the main wire 4 or may be attached by appropriate means. The point is that when the water level drops as shown in Figure 2, the upper part of the main rope on the downstream side, which would normally slacken, should float as shown in the figure. Therefore, the sub-floats 6 do not necessarily have to be closely connected as shown in the figure;
They may be provided at appropriate intervals as shown in the figure.

In addition, 7 in the figure is a rope protection tube provided below the sub-float 6 of the main rope 4, which prevents damage to the main rope in the event that contact between the weight and the main rope occurs. However, this is not necessarily necessary.

(Effect of the invention) Since the present invention has the above configuration,
For example, at low tide, the tide flows in the direction of the arrow and the water level reaches the second level.
When the rope is lowered as shown in the figure, the main rope 4 on the downstream side (right side) of the main float 1 does not slacken and its upper part floats due to the action of the sub-float 6, and the part beyond the lowest sub-float is connected to the anchor 5. It will be in a stretched state as before.

Therefore, in this state, even if the weight 2 at the lower end swings due to currents or waves acting on the curtain body 3, the main rope 4 will not come into contact with it because it is floating on the water surface. It also does not dimensionally contact the main rope that is stretched between it and the anchor at its tip.

As mentioned above, the present invention has a simple structure, makes it easy to install the sub-float, and avoids contact between the weight and the main rope, so the main rope will not be damaged even if it is installed for a long time. Therefore, it has high industrial applicability.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example of the present invention, Fig. 2 is a side view of the same at low tide, Fig. 3 is a side view of another embodiment, Fig. 4 is a side view of the conventional product, and Fig. 5 is a side view of the present invention. FIG. 4 is a side view at low tide, and FIG. 6 is a side view of another conventional embodiment. 1... Main float, 2... Weight, 3... Curtain body, 4... Main rope, 5... Anchor, 6
...Sub float, 7...Rope protection tube,
8...Sub anchor, 9...Sub rope.

Claims (1)

[Claims for Utility Model Registration] 1. A curtain body 3 with a weight 2 at the lower end is suspended from the lower part of the main float 1, and main ropes 4, 4 are connected to the left and right sides of the curtain body in an inverted V shape. and attach the lower end of this main rope to anchors 5 and 5.
A plurality of sub-floats 6 are provided between the base of the main ropes 4, 4 and the main float 1 to a position having approximately the same dimensions as the length of the curtain-like body 3. A pollution diffusion prevention curtain characterized by: 2. The pollution diffusion prevention curtain according to claim 1, wherein the main rope 4 has a rope protection tube 7 below the sub-float 6.