JPH01304378A - Fishing net detector - Google Patents

Abstract

PURPOSE:To monitor the state of a fishing net by providing ultrasonic vibrators to prescribed points of the fishing net and transmitting and receiving ultrasonic waves between each vibrator. CONSTITUTION:Ultrasonic vibrators 6a-6e are respectively provided to prescribed points, such as the entrance section 5a and end section 5b, of a fishing net 5 being pulled by fishing boats through ropes 4. The vibrators 6a-6e are connected with a controller 7 and the signal of the controller 7 is transmitted from a transmitter 8 and received by a receiver 10 mounted on the fishing boats through the signals lines 9 provided to the ropes 4. In other words, signals are transmitted and received among the ultrasonic vibrators 6a-6e provided to prescribed points of the fishing net 5 under the control of the controller 7 so as to monitor the state of the fishing net 5 by calculating the distances among the vibrators 6a-6e and displaying 10 calculated signal on the boats. Moreover, when the signal of the controller 7 is transmitted and received after converting the signal into ultrasonic waves, the state of the finishing net 5 can be monitored.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a fishing net detection device that monitors the condition of a net, such as a bottom trawler, by attaching an ultrasonic transducer to the device.

Prior Art Generally, when fishing with bottom trawl nets, it is not possible to know what condition the fishing net is in under the sea. Therefore, if the opening of the net is not opened sufficiently,
If the end 3 of the fishing net 1 is raised higher than the entrance 2 of the fishing net 1 as shown in Figure 8(b), or if the end 3 of the fishing net 1 is lower than the entrance 2 of the fishing net 1 as shown in Figure 8(b), the amount of fish caught will decrease. There are drawbacks to doing so.

[Problem to be solved by the invention] However, in the past, there has been no attempt to detect the condition of the fishing net; the current situation is to simply throw in the fishing net and pull it out. I had no idea what was going on.

The present invention involves attaching an ultrasonic vibrator to a predetermined location of a fishing net,
A fishing net that monitors the condition of a fishing net by transmitting and receiving ultrasonic waves between each ultrasonic transducer and detecting whether or not the ultrasonic transducers are at a predetermined distance based on the time calculated between the ultrasonic transducers. The purpose is to provide detection equipment.

[Means for Solving the Problems] In order to achieve the above object, the present invention attaches ultrasonic transducers to predetermined locations of a fishing net, and connects the fishing net or the fishing net to a rope from the ultrasonic transducer. The controller is equipped with a control device that processes signals, sends and receives ultrasonic waves between the ultrasonic transducers, calculates the distance between the ultrasonic transducers, and transmits the calculated signal from the control device. .

Further, the signal from the signal processing circuit is received by a receiving device provided on the ship via a signal line provided on the rope.

Furthermore, an ultrasonic transducer is attached to a predetermined location on the fishing net, a control device that processes the signal from the ultrasonic transducer is attached to the fishing net or a rope pulling the fishing net, and a transmission device that transmits the signal to the control device using ultrasonic waves is installed. The receiving device is equipped with a reliable ultrasonic transducer and an ultrasonic transducer for receiving ultrasonic waves.

Further, the ultrasonic transducer may be a multi-frequency transducer.

Furthermore, the transmitter is provided with frequency modulation means for generating signals of a plurality of frequencies from the ultrasonic transducer.

Alternatively, the transmitting ultrasonic transducer and the ultrasonic transducer may be provided integrally.

[Function] According to the present invention, signals are transmitted and received between the ultrasonic transducers provided at predetermined locations on the fishing net, the distance between the ultrasonic transducers is calculated by the arithmetic processing unit, and the calculated signal is transmitted and received. The condition of the fishing net can be detected by displaying it on the boat, and by converting signals from the processing unit into ultrasonic waves and transmitting and receiving them.

The state of the fishing net can be detected without the need for a signal cable.

[Embodiment] Fig. 1 is a schematic diagram of a fishing net detection device according to an embodiment of the present invention. Ultrasonic transducers 6a, 6b, 6c, 6 are provided at the inlet portion 5a and the terminal portion 5b, respectively.
d and 6e are installed.

Referring to FIG. 2, these ultrasonic transducers 6a to 6c
is connected to a control device 7, and a signal from the control device 7 is received from a transmitter 8 via a signal line 9 provided on the rope 4 by a receiver 10 provided on the ship.

Since the fishing net detection device of this embodiment is configured in this way, the ultrasonic transducers 6a and 6b, 6a and 6c, 6a and 6d, and 6b
and 60. Between 6b and 6d, 6c and 6d, 6c and 6e, and 6d and 60, a burst wave is transmitted from one ultrasonic transducer (for example, 6a) as shown in FIG. Figure 3 (
As shown in FIG. 3(c), the burst wave is received by another ultrasonic transducer (for example, 6b), and the received wave is detected as shown in FIG. 3(c) to detect the time td between transmission and reception. Also,
The ultrasonic transducers 6a and 6d each emit ultrasonic waves and receive the reflected waves.
By detecting the distance between the water surface 11 and the water surface 6d and the water surface 11, the state of the fishing net 5 can be detected at all times.

Therefore, based on the detected signal, the speed of the boat is controlled so that the entrance portion 5a of the fishing net 5 is sufficiently opened, and the end @ 5
The depth of the fishing net 5 can be controlled so that it does not become two inches or lower than the entrance portion 5a, and the depth of the entrance portion 5a of the fishing net 5 can also be controlled.

Referring to FIG. 4, the transducer 12 of the other embodiment includes arc-shaped ultrasonic transducers 14 and 15 mounted around a cylindrical asymmetric Langevin type multi-oscillator 13.
2 is attached to the fishing net 5 instead of the ultrasonic transducers 68 to 6e shown in FIG. and a cylindrical ultrasonic transducer]4
．． 15 is used to detect the distance between adjacent transducers, and the asymmetric Langevin type multi-oscillator 13 transmits a signal of the detected distance between each transducer 12 to the ship's receiver by three frequencies. used to.

Referring to FIG. 5, in another embodiment of the invention using the transducer of FIG. 4, the ultrasonic transducer 14, j5 of the transducer 12 is used as the ultrasonic transducer, and the An asymmetric Langevin type multi-oscillator 16 is connected instead, and an asymmetric Langevin-type multi-oscillator is also connected to the receiver 10]
7 is connected.

For example, 23k l(z, 45k
If tlz and 98kllz correspond to Oll and 2, respectively, data on the distance between each vibrator 12 can be sent by a combination of three signals. The table below is an example of coating when the signals transmitted and received by the asymmetric Langevin type multi-oscillator 16, ]7 in Fig. 5 are divided into 10 levels. - is an index signal, and the remaining 4 pins 1- indicate data.

Note that as the asymmetric Langevin type multi-oscillator 13 of the transducer 2, in addition to the three-frequency transducer, a two-frequency transducer or a four-frequency transducer or more can be used.

(Table) In addition, in FIG. 2, an asymmetric Langevin type multi-oscillator is used in place of the transmitter 8, and data can be transmitted and received in the same manner using the ultrasonic communication method as described above.

[Effects of the Invention] Since the present invention is configured as described above, ultrasonic transducers are attached to predetermined locations on a fishing net, and the distance between the ultrasonic transducers is determined by transmitting and receiving ultrasonic waves. The state of the fishing net can be detected by detecting the arrival time of the ultrasonic wave and sending this detection signal to the receiver using a transmitter or an asymmetric Langevin multi-oscillator. It has the advantage that it can be controlled to bring it into a normal state, thereby increasing the amount of fish caught.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the state of a fishing net equipped with a fishing net detection device according to an embodiment of the present invention, FIG. 2 is a block diagram of a fishing net detection device according to an embodiment of the present invention, and FIG. 3 is a diagram showing the fishing net shown in FIG. 1. A waveform diagram of ultrasonic waves transmitted and received by the detection device, FIG. 4 is a perspective view of another ultrasonic transducer used in the fishing net detection device of FIG. 1, and FIG. 5 is a fishing net of another embodiment of the present invention. The detection device block diagram, FIGS. 6(a) and 6(b), are schematic illustrations of the state of the fishing net in the sea. 4... Robe, 5... Fishing net, 6... Ultrasonic transducer, 7... Control device, Death... Transmitter, 9... Signal line,
10... Receiver, 11... Water surface, 12... Oscillator, 13... Asymmetric Langevin type multi-oscillator, 14
．． 15...Ultrasonic vibrator・

Claims (1)

[Claims] 1. An ultrasonic transducer is attached to each predetermined location of a fishing net, a control device for processing a signal from the ultrasonic transducer is attached to the fishing net or a rope pulling the fishing net, and A fishing net detection device characterized in that ultrasonic waves are transmitted and received between sonic transducers, a distance between the ultrasonic transducers is calculated by a control device, and the calculated signal is transmitted from a transmitter. 2. The fishing net detection device according to claim 1, wherein the signal from the transmitter is received by a receiving device provided on board the ship via a signal line provided on the rope. 3. Attach an ultrasonic transducer to a predetermined location on a fishing net, attach a control device to the fishing net or a rope pulling the fishing net to process the signal from the ultrasonic transducer, and send the signal to the control device to transmit the ultrasonic wave. 1. A fishing net detection device, characterized in that a receiving device is equipped with a transmitting ultrasonic transducer for transmitting ultrasonic waves, and a receiving device is provided with an ultrasonic transducer for receiving the ultrasonic waves. 4. The fishing net detection device according to claim 3, wherein the ultrasonic transducer is a multi-frequency transducer. 5. The fishing net detection device according to claim 4, wherein the transmitter is provided with frequency modulation means for generating signals of a plurality of frequencies from the ultrasonic transducer. 6. The fishing net detection device according to claim 3, wherein the transmitting ultrasonic transducer and the ultrasonic transducer are integrated.