JPS58142280A - Method and apparatus for finding signs of fish - Google Patents

Abstract

PURPOSE:To enable immediate identification of exact conditions in the advance of fish by arranging a plurality of ultrasonic wave transmitting and receiving elements in the perimeter of a cylindrical body with a transmitter/receiver for detecting ultrasonic waves set below the water surface at the inlet of a pocket section to which fish in a stationary net advances. CONSTITUTION:The position of a detector is set somewhere at the second inlet 5. The detector S' adopted is so arranged that one set each of transmitting/ receiving elements (f) (for example, 10 in the number) is mounted at fixed intervals around the cylinder of a cylindrical body 7. An ultrasonic wave is transmitted at an fixed time interval from the elements (f) and received therewith. An ultrasonic wave transmitted from the detector S' at the second inlet 5 constitutes a circular belt thereof with a fixed width and cover the inlet 5 entirely. In other words, whenever fish passes through the inlet, it always cross the circular belt of the ultrasonic wave thereby enabling accurate catching of all signs of fish with the ultrasonic wave.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fish shadow detection method and device for detecting whether or not a school of fish that has entered a fixed net has entered a capture pocket. The purpose is to be able to reliably detect whether or not a school of fish has entered the pocket by installing an ultrasonic detector at the pocket and detecting a school of fish passing through it.

A known method is to use a fish net detector to detect fish from a remote location, but the drawback is that the ultrasonic waves do not reach a sufficient range, and as a result, the fish that enter the fish are not completely detected. ing.

FIG. 1 shows a typical fixed net (T) device, which is set in the water by a number of anchors (A). At this point, the school of fish enters the swimming part (3) from the first population (2) along the vertical joint (1) as shown by the arrow, and gradually moves to the left pocket part [also called "kato"] (4
).

This pocket part (4) has a bag-like structure with a bottom, and a second population (5) is provided there, and by passing through this part, a school of fish enters the pocket part (4). and was completely captured.

Conventionally, this blur is detected by a configuration as shown in point A at point vessel(
S) suspended 1 to 1.5 m below the water surface.

We are currently detecting fish that have entered part (4).

However, according to this method, as shown in Figure 3, ultrasonic waves (
The spread of a) is in the range of 45 to 90 from the transmission position,
Since the fish do not necessarily pass through that area, it is not possible to catch the fish in the off-center area (4f, etc.), and therefore it is not possible to completely grasp the black number in the pocket area (4).

In this case, this invention provides the position of the detector at the second population (5) as shown in the above-mentioned Figure 3, and the cylindrical part between the detectors as shown in Figures 4a and 4b. body (7)
A configuration is adopted in which a plurality of (for example, about 10) transmitting/receiving elements (f) for each group are arranged at regular intervals around the cylinder. Then, each element (f) transmits and receives ultrasonic waves after a certain period of time. According to this, the fifth
As shown in the figure, this detector (E
The ultrasonic wave emitted from +) is an annular band (7) of constant width and is
It will cover all of the second population (5).

That is, when a fish passes through this inlet, it always crosses the annular band (7) of ultrasonic waves, and all fish images are reliably captured by these ultrasonic waves. In other words, the transmitting and receiving elements (f) arranged in a ring are operated one time by sending pulse inputs by wire or wirelessly from land, buoys, ships, etc. At that time, time is taken for each transmitting and receiving element (f) to avoid interference of mutual ultrasonic waves. By emitting ultrasonic waves for several seconds at a time, detecting when the ultrasonic waves hit the fish and detecting them, and then emitting them from an adjacent element and detecting them, and repeating this sequentially, an annular band of ultrasonic waves ( 7) is used as an ultrasonic source, and thereby a school of fish passing through the second population (5) is detected and sensed by a separate recorder.

When the transmitting/receiving elements (f) are arranged in the cylindrical main body (7), they are usually placed over approximately half the circumference of the lower surface, but they may be placed over the entire circumference. It is also possible to avoid mutual interference of ultrasonic waves by moving the ultrasonic waves sequentially to adjacent ones over time, or by dividing the ultrasonic waves into groups and having them transmit alternately.

According to the method of this invention, vertical tightening (
When a school of fish that has passed through the first population (2) and entered the swimming part (3) from 1) enters the second population (5) of the pocket part (4), the superposition of the annular band near this entrance As a method and device that can immediately determine the exact situation of fish intrusion by sensing sound waves, this method will bring significant progress to future set net fishing methods.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the installed state of a fixed net, Fig. 2 is a perspective view showing a conventional ultrasonic detection transceiver, Fig. 3 is a longitudinal cross-sectional view of the vicinity of the pocket of the fixed net shown in Fig. 1, and Fig. 4. a is a perspective view of the detector of the present invention and a diagram explaining the situation in which ultrasonic waves are generated; FIG. 4 is an enlarged cross-sectional view taken along the line E in FIG. FIG. 2 is an explanatory diagram of the present invention as seen from above, with two pockets and a pocket section. (g)・・・・・・Fixed net (1)・・・
・・・・・・・・・・・・Vertical tightening ←）・・・・・・
Anchor (2)・・・・・・・・・First population (3)・・・・・・Swimming club (4)・
...Pocket part (5) ...Second population (S). (S)'・・・・・・・・・・・・
Detector (6)...Conical body (7)...
... Inner cylindrical body α) ... Ultrasonic annular band, (a
)・・・・・・・・・・・・・・・Ultrasound (f)...
Transmitting/receiving element patent applicant Kyuroku Co., Ltd. Figure 2 Figure 6

Claims (1)

[Claims] 1. An ultrasonic detection transmitting/receiving device is installed below the water surface at the entrance of the pocket into which the fish school of a fixed net fishing net enters, and a plurality of ultrasonic power sources do not interfere with each other in the shadows of fish passing through the device.) A method for detecting fish in a fixed net, characterized by detecting using an emitted ultrasonic band. 2. A fish detection device characterized by having a plurality of ultrasonic transmitting and receiving elements arranged around a cylindrical body.