JPS6049364B2 - Combination corner reflector - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in radar reflectors.

In order to improve so-called radar visibility, radar reflectors combined with metal conductors have been installed in buoys, small ships, etc. that have a weak reflection intensity against radar radio waves. In particular, as FRP small boats and buoys have been frequently used recently, for the purpose of ensuring safety of navigation at sea.
It has become common sense to equip these with radar reflectors. These conventional radar reflectors are either a corner reflector that combines metal veneers in the shape of a Ξ pyramid, as shown in Figure 1, or a corner reflector that combines three circular veneers with the same radius in a cross section orthogonal to each other, as shown in Figure 2. Corner reflectors configured by combining them in a shape, or reflectors in which 4 to 8 reflectors are arranged in an annular shape with their openings facing outward, as shown in FIG. 3, are used.

(The arrows in Figure 1 indicate the direction of radio wave input and reflection.) It is well known that both structures have high reflection efficiency and have an extremely large reflection effect even though they are small structures. For example, the above corner reflector with one side of 30C771 is
It has a reflection effect comparable to that of a flat metal plate with a reflection area of 15- facing directly in the direction of arrival of radar radio waves. This is because the reflector has directivity in the direction in which radio waves are reflected, and is configured to have strong directivity.
Even though it is small, it can provide the same reflective effect as a large flat metal plate. However, it is technically difficult to arrange these conventional corner reflectors evenly on all four sides, and it is even more difficult to provide all-round directionality to the incident radio waves, as shown in Figure 3. Although arranging 5 to 8 reflectors in a ring with the openings of the reflectors facing outward may serve some purpose, the assembly becomes complicated and requires a lot of man-hours.
However, configuring them in an accurate arrangement requires skill, and one drawback is that the shape is also large.

The corner reflector shown in Figure 2, which is constructed by combining circular single plates in a cross shape, has eight openings. As shown in FIG. 2b and its plan view c, although the directivity in the horizontal direction was good, it had the disadvantage of being biased in two directions. The present invention is a combination of four corner reflectors in a state in which a ball can be inserted through the center.The directivity of each corner reflector is in the horizontal direction, so that they are oriented equally in four directions, and the ball, etc. This is a combination corner reflector that is extremely easy to install in a balanced state, is small and lightweight, and is easy to manufacture.If necessary, two sets of these can be stacked and used to achieve non-directionality in a horizontal plane. This makes it possible to easily provide a combination corner reflector.

The contents will be explained in detail below according to the embodiments shown in the drawings. FIG. 4a is a perspective view of a corner reflector body constituted by a triangular radio wave reflecting plane plate having a metal surface.

A set of ±4 corner reflector elements is shown in the plan view of Fig. 4b and its front view (Fig. 4b(7)A).
View) c and oblique side view (Fig. 4 b (7) B view) d
They are combined around the vertical axis 3 to form a set of corner reflectors as shown in FIG. That is, one surface of the three planar plates constituting each corner reflector element body ± is arranged vertically at 90 degrees to each other around the three vertical axes, and the ridge lines 1'' of the other two surfaces are horizontal and adjacent in the same rotation direction. The vertical plane 1'' of the corner reflector element body 1 is in contact with the back, and the apex 1'''' of one corner reflector element ± and the apex 1'''' of the other adjacent corner reflector element body 1 1 by placing them in the same rotation direction with a certain distance 1 between them.
This constitutes a set of combination corner reflectors I.
In order to connect the 54 corner reflector bodies, attach the mounting piece 5, which has a triangular cross section as shown in FIG. and the back surface of the sloped surface of the adjacent element body ±, or by attaching the attachment piece 6, which has a notch 6'' in the center with a cross section 6'', as shown in FIG. 6a. As shown in FIG. 6b, the combined corner reflector I can be easily and firmly configured by inserting and fixing the parts as shown in FIG. The combined corner reflector can also be strongly constructed by inserting a square prism 3'' having a vertical axis 3 in step 1 and gluing the vertical surface 1'' of the corner reflector body ± to this. As illustrated in FIG. 7, by inserting a light buoy marker into the through hole 4 of the square column 3'', the combination corner reflector I can be mounted in a state parallel to the marker. Figure 8 shows a bottomed cylindrical container 7 made of a material with low loss against radar waves, such as polyethylene or polystyrene resin, which has a structure in which a prism 9 with a through hole 8 protrudes from the center of the interior. ing. If the combined corner reflector I is inserted into the container 7, the corner reflector can be stably held in the container 7 without causing any displacement or the like. Further, by covering and sealing the upper part of the container 7, the reflector is protected from external influences such as wind and waves, and can be made into a weather-resistant and stable reflector. When placed in such a container, the material constituting the corner reflector can be an extremely thin metal plate, such as aluminum foil pasted onto a thin resin plate, which is economical and extremely lightweight. can be taken as a thing. In addition, when kneading, the reflected state of the incident radio waves is shown by the chain line in Figure 8b, and the four beams exhibiting radio wave reflection characteristics form a four-leaf clover-shaped pattern at equal intervals in the horizontal plane. do. Next, if two sets of combined corner reflectors housed in a cylindrical container 7 are combined in two stages, upper and lower, and rotated by 45 degrees in the horizontal direction, the radio wave reflection characteristics of the opening of the corner reflectors can be adjusted. are symmetrical 8 points facing outward at equal 45 degree intervals in the horizontal plane.
Form a pattern of petals.

As a result, the reflected beam is in an ideal non-directional state in the horizontal plane, as shown by the chain line in FIG. 9b. Since a ball or the like can be inserted through the through hole in the center of the container 7, it is extremely easy to attach the corner reflector to the ball or the like. The above is
Although we have described a case in which the reflective flat plate of a corner reflector is constructed from a triangular flat plate, as shown in Figure 10a, a corner reflector body constructed using a square flat plate can be constructed using the same procedure as shown in Figure 4. A combination corner reflector as shown in FIGS. 10b-d may be constructed. FIG. 11 shows that when the combined corner reflector is used while being housed in a cylindrical container, the projecting outer peripheral edge of the reflector is shaped so as to be in contact with the inner peripheral surface of the container to effectively utilize the space inside the container. This shows a corner reflector that has a wider reflection area for radio waves and also has the effect of further increasing the stability of the corner reflector.

According to the present invention, when four corner reflector bodies are combined, by forming a hollow part in the center, the combined corner reflector can be attached to the columnar body by penetrating the center part. This makes it easy to install the device evenly on the left and right sides.

Therefore, when it is attached to a light buoy's marker pole, etc., there is no fear that an unbalanced load will be applied to the light buoy. In addition, if the mounting piece is made of closed cell resin and the cylindrical container is made of resin such as polyethylene or polystyrene, it is lightweight, easy to process, and can be assembled accurately. A compact and lightweight combination corner reflector with good reflection characteristics can be obtained.

The above has been described in detail exclusively as a combination corner reflector for radar radio waves, but other uses include sound waves,
Similar effects can be expected with light waves as with radio waves.

For example, it can be used for omnidirectional signs installed to mark intersections on roads, etc., for the purpose of strongly reflecting the beam light from the headlights of motor vehicles. In this case, the corner reflector element is composed of an optical plane mirror, and the cylindrical container covering the combined corner reflector is made of a transparent plastic material. Furthermore, if the purpose is to obtain colored reflected light for white incident light, the outer container may be colored and made transparent, or the optical plane mirror serving as the element of the corner reflector may be colored. Even in the case of omnidirectional use on land, according to the configuration of the present invention, it is possible to provide a reflector that is easy to mount, is small and lightweight, and has good reflection characteristics.

[Brief explanation of the drawing]

Figure 1 is a front view of a conventional corner reflector, Figure 2a is a perspective view of a conventional corner reflector combining circular single plates, Figures 2B and c are explanatory diagrams showing the direction of radio wave reflection, and Figure 3. 4 is a front view of a conventional all-around directional corner reflector, and FIGS. 4a to 4d show the configuration of a combination corner reflector according to the present invention, in which a triangular flat plate is used as the reflective flat plate constituting the corner reflector alone. An example is also shown in FIG.
A perspective view of a prism is shown. Fig. 5 a1 Fig. 6 a is a perspective view of the corner reflector body mounting piece, Fig. 5 b, Fig. 6 b is a diagram of its installation state, and Fig. 7 shows the combination corner reflector according to the present invention attached to a light buoy. FIGS. 8A and 8B are a partially cutaway front view and a plan view thereof of a cylindrical container for storing a combined corner reflector, and FIGS. 9A and 9B are
b is a front view and a cutaway plan view of two sets of combined corner reflectors stored in a cylindrical container stacked in two layers, the first
Figures 0 a to d are a perspective view of a corner reflector element constructed using a square single plate as a reflective plane plate, a plan view, a front view, and a diagonal side view of a combined corner reflector constructed by combining this corner reflector element. , FIG. 11A is a perspective view of a corner reflector body constructed by protruding the protruding edge of the reflective flat/face plate into contact with the inner circumferential surface of a cylindrical container, and FIG. 11B
, c are a plan view and a front view of the combined corner reflector constructed from the four corner reflector bodies shown in FIG. 11a. ±
...Corner reflector element, 1"...Vertical plane, Bi...Ridge line, 1"""...Vertex, 1""""...Slanted plane , 1... Combination corner reflector, 3... Vertical axis, 7...
・Cylindrical container.

Claims (1)

[Claims] 1. In a combination corner reflector in which four corner reflector elements each consisting of three planes orthogonal to each other are arranged facing outward in the same direction around a vertical axis, one surface of each element is arranged vertically. The ridge lines formed by the other two surfaces are arranged horizontally, and the horizontal ridge line of the other element body is positioned in contact with the back surface of the vertical plane of the element body 1, and the two The vertex of the element body of is 1
Combination corner reflectors placed at a fixed distance. 2. The combination corner reflector according to claim 1, wherein two sets of combination corner reflectors are stacked coaxially in two stages, upper and lower, and are rotated 45 degrees from each other. 3. The combination corner reflector according to claim 1 or 2, which is housed in a cylindrical container.