SU1764587A1 - Device for diagnosing mastitis - Google Patents

Abstract

The invention relates to agricultural machinery, in particular, to devices for diagnosing the incidence of mastitis in dairy herd cows. The purpose of the invention is to improve the accuracy of diagnosis and simplify the device. The device contains sensors 1-4 temperature and sensors 5-8 conductivity of milk. Sensors 1, 2 and 5, 6 form the opposite shoulders of one measuring bridge, while sensors 3,4 and 7, 8 form the opposite shoulders of another measuring bridge. An increase in temperature (inflammation) causes an increase in the resistance of sensors 1–4, and an increase in the acidity of milk increases its conductivity and a decrease in the resistance of sensors 5–8. With mastitis, the electrical parameters of the arms of the measuring bridges change, and with the opposite sign. The sensitivity of the measuring bridges is greatly increased. 1 hp f-ly, 2 ill.

Description

The invention relates to agricultural machinery, in particular, to devices for diagnosing the incidence of mastitis in dairy herd cows.

The purpose of the invention is to improve the accuracy of diagnosis and simplify the device.

Figure 1 shows the functional block diagram of the device; figure 2 - diagram of the recording unit.

The device contains temperature sensors 1-4, forming the opposite arms of two measuring bridges, electrical conductivity sensors 5, 6, 7, 8, which together with adjusted resistors 9-12 form the other opposite arms of the same bridges, fixed resistor 13, power supply 14, amplifiers 15 and 16, threshold elements 17 and 18 with an amplifier 19, a threshold value adjuster 20, a constant resistor 21 and an LED 22 each.

The device works as follows.

Sensors 1-4 and 5-8 of temperature and electrical conductivity of milk are installed in pairs in each of four teat cups, i.e. pairs of sensors 1 and 5, 2 and 6, 6, 3 and 7, 4 and 8 are formed. When a cow becomes sick with mastitis, the temperature and acidity of the milk in one, several or all teat cups increases. In this case, the resistance of the temperature sensors 1-4 increases and the resistance of the electrical conductivity sensors 5-8 drops. Since temperature sensors 1-4 form one pair of opposite arms of each measuring bridge, and electrical conductivity sensors 5-8 form another pair of each measuring bridge, at the output of the bridge circuit

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voltage, the value of which is determined by the difference of the products of the resistance values of these opposite arms. The sensitivity of the considered measuring bridge is much higher than the sensitivity of a conventional bridge with one sensor. The output signal appears when any parameter of temperature or conductivity changes, and it increases dramatically with a simultaneous change (directly follows from the principle of operation of the bridge circuit).

The work of both measuring bridges is similar. Trimmer resistors 9–12 are used to tune the circuit under production conditions, since the electrical conductivity of milk is different for different cows.

The signals of the measuring bridges are amplified by amplifiers 15 and 16 and are fed to the threshold elements 17 and 1. The triggering of the threshold circuit of any of them signals the presence of mastitis.

The measuring bridges are powered from the power supply unit 14 through the fixed resistor 13, which limits the amount of current through the temperature sensors 1-4 in order to prevent their self-heating. Amplifier power 15.16 and threshold

Fig, 1

elements 17, 18 are also provided from power supply 14.

Claims (2)

1. Device for diagnosing mastitis, containing constant and trim resistors, temperature sensors and electrical conductivity of milk, included in the shoulders of the respective measuring bridges, the outputs of which are connected by means of amplifiers with threshold elements, in order to improve the accuracy of diagnosis and simplify the design devices, it is equipped with second, third and fourth trimming resistors, while the temperature and electrical conductivity sensors of milk are combined into two measuring bridges, with this m temperature sensors are incorporated into opposite arms of each bridge, and milk conductivity sensors are connected in series with Trimmer and incorporated into other opposite arms of respective bridges. 2. Device pop. 1, characterized in that the threshold elements are made in the form of a threshold circuit and an optical indicator connected in series. From / 5 CV 20 Hz3 Fzg.2