SU1308305A1 - Apparatus for determining trawl skewing - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to industrial fishing and is aimed at increasing accuracy. The device is equipped with a resistor divider and three switches. The midpoint of the resistor divider 8, 9 is connected via a single switch to the electrode intended to be mounted on the trawl along its longitudinal axis and to the input of the indicator. The extreme points of the resistor through the other two switches are connected to the corresponding two other electrodes and to the output of the generator. The second output of the generator is connected to the second input of the indicator. The resistance ratio of the resistor divider is R .: R, (1 + 2cf,: Uo): (1-2Q,: U (,), where q, is the potential of the electrode attached to the longitudinal axis of the trawl when the tilt of the trajectory is about an angle; and - voltage at the generator output, i.e., on electrodes located symmetrically relative to the longitudinal axis of the trawl. The device eliminates the dependence of the instrument readings on the electrical conductivity of the water, which increases the accuracy. 2 or (O (L 00 00 00 ate 1 Fig. 2

Description

The invention relates to industrial fisheries, in particular to trawl parameter monitoring devices, and can be used as a device for determining trawl skew.

The purpose of the invention is to improve the accuracy of the measurement of the trawl skew.

Fig. I shows the layout of the device on the trawl; FIG. 2 is a block diagram of a device for determining a trawl skew.

The device comprises a generator 1 connected by means of the insulated wires 2 and 3 to the electrodes 4 and

5, and through switches 6 and 7 - with the ends of the resistor divider 8 and 9, the middle point of which is connected to the electrode through switch 10

11, which, in turn, via insulated wire 12 is connected to the input of the indicator 13, the other input of which is connected electrically to the generator 1 by means of communication 14, and the output of the indicator through the communication line 15 to the ship's receiving device 16. In this case, the electrodes 4 and 5 are designed to be fixed on the trawl 17 symmetrically to its longitudinal axis, and electrode 11 to be fixed to the longitudinal axis of the trawl.

The device for determining the trawl skew works as follows

In measurement mode, switches

6,7 and 10 are open. Electrodes 4 and 5 from generator 1 apply a voltage of magnitude Up, as a result of which a dipole field is created in water, the zero equipotential of which coincides with the longitudinal axis of the trawl, so that in the absence of a skew, the potential of electrode 11 is zero. When the trajectory is skewed, which causes a deviation of the longitudinal axis of the trawl by an angle about its symmetric position, the potential cf arises at the electrode 11, whose magnitude is proportional to the angle oi. At the same time, the distortions to the right or to the left, respectively, are opposite to the values of the potential phase Cf, relative to the voltage front. The magnitude and phase of the potential, cf, is recorded by the indicator 13, and the magnitude of the angle "i is displayed by the ship's receiving device 16. To ensure compliance with the readings of the ship's receiving device 16,

The muddy skew angle value requires pre-calibration on board the vessel. In calibration mode, resistor divider 8 and 9 are connected to electrodes 4, 5 and 11 by means of closed switches 6j7 and 10. The ratio of the resistances of resistors 8 and 9 is equal to

where R and R, are the resistance values of resistors 8 and 9, respectively. At the specified ratio of resistances of resistors 8 and 9, the potential of the electrode 11 in the calibration mode takes the value Cf,.

The value of the ratio cp, / U is determined previously experimentally or theoretically. Theoretically expected value of the ratio

is by the formula

 sino6 + --7 g

de about - the skew angle;

and - the equivalent radius of the electrodes 4 and 5; d - half the distance between

electrodes 4 and 5; d is the distance between the electrode 11 and the middle of the straight line connecting the electrodes 4 and 5.

As a result, {the implementation of the proposed technical device eliminates the influence of the electrical conductivity of water on the readings of the instrument, and therefore accuracy is spun.

Claims (1)

Invention Formula An apparatus for detecting a skewed trawl, comprising an electrical signal generator and three electrodes, one of which is designed for reinforcement on the trawl along its longitudinal axis and connected electrically with the indicator, and the other two for installation on the trawl symmetrically 31 The longitudinal axis and electrically connected with the generator, characterized in that, in order to increase accuracy, it is equipped with a resistor divider and three switches, while the middle point of the resistor divider is connected by means of one switch to the electrode intended for mounting on the trawl of its longitudinal axis, and to the input of the indicator, and its extreme points are connected via two other switches to the corresponding two other electrodes and to the output of the generator, whose input is connected to the second input of the indicator, and niya 3083054 resistance of the resistor divider is equal to 5i R, where (is the potential of the electrode fixed on the longitudinal axis of the trawl when the bias trawl at angle oi; and is the voltage at the generator output, i.e. on electrodes located symmetrically with respect to the longitudinal axis of the trawl. Compiled by G. Bogacheva Editor A.Vorovich Tehred V.Kadar Proofreader M.Demchik Order 1654/5 Edition 630 Subscription VNYIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35,: Raushsk nab., 4/5 -Production and printing company, Uzhgorod, st. Project, 4 Phage. one