SU1690669A1 - Device for examination of human thermocontrolling reactions - Google Patents

Abstract

The invention relates to medical technology and can be used in the study and control of a functional state of a person, namely under the action of a thermal factor. The purpose of the invention is to improve the accuracy of the study of thermoregulatory reactions of a person by simultaneously recording electrical resistance and sweating from the same area of the human body. The device contains a sensor 1, a power supply unit, bridge circuits 2, 3, amplifiers 5, 6 and a recorder 7. This goal is achieved due to the fact that the active electrode of sensor 1 contains electrically conductive rods with a specified resistance for detecting sweating and electrically conductive rods with zero resistance registering the electrical resistance of the skin, while they are connected to the corresponding bridge circuits 2, 3, amplifiers 5, 6, and the recorder 7. 1 Cp. f-ly, 5 ill. THX

Description

The invention relates to medical technology and can be used in the study and control of the functional state of the human body, and / or under the action of the thermal factor.

The aim of the invention is to improve the accuracy of the study of human thermoregulatory reactions by simultaneously registering electrical resistance and sweating from the same area of the human body.

Figure 1 presents the block diagram of the device; figure 2 - conventional image of the active electrode of the sensor; on fig.Z - the conventional image of the passive electrode of the sensor; 4 and 5 are equivalent circuits explaining the principle of operation of the device.

The device consists of a stable current generator 1 for a grounded load, which allows setting a current within 0.2–200 µA, bridge circuits 2 and 3, sensor 4, consisting of active and passive electrodes, amplifiers 5 and 6, and registration unit 7 representing two voltmeters.

Sensor 4 consists of 8 active and passive 9 electrodes. The number 10 denotes the working surface (leather). The active electrode 9 consists of a housing 11 with stops. The stops are designed for stable fixation of the active electrode 9 on the working surface 10 and do not interfere with the action of heat irritant on the working surface, for example, the entry of thermal air into the space 12, since the body 11

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the active electrode 8 does not touch the working surface 10. Through the housing 11 perpendicular to the working surface 10, electrically conducting rods 13 with a predetermined resistance are passed to electroconductive rods 14c with zero resistance. Electric resistance rods 14 with zero resistance can be made of a superconducting drive, a PNT-0.5-1045 niobite-titanium alloy. Electroconductive rods 13 and 14 are staggered in a staggered manner at a distance of 5-200 µm, which ensures the registration of information about electrical resistance and perspiration from the same skin area.

The device works as follows.

Passive electrode 9 is installed on the subject's leg. The active electrode 8 on the hand of the test. The surface of the hand is also important in human thermoregulation. The subject is exposed to thermal effects (general or local), for example, heated air. When the electrical resistance changes, the signal from the passive electrode 9 and electrically conductive rods 14 with zero resistance of the active electrode 8 goes through the 3 m bridge circuit to the amplifier 6 to the recorder 7. At the same time, perspiration is released, which closes the electrically conductive rods 13 with the specified resistance of the active electrode 8. The signal from the passive electrode 9 and the electrically conductive rods 13 through the bridge circuit 2, the amplifier 5 is fed to the recorder 7. In this case, the magnitude of the electrical resistance is recorded Skin laziness and the amount of perspiration. The amount of perspiration in this case is expressed by resistance and depends on the number of subsequently closed electrically conductive rods 13 with a given resistance. The difference between the obtained value and the electrical resistance of the skin at the same time point characterizes the level of perspiration in the subjects. And since the electrical resistance of the skin changes with heat exposure, physical work, then taking its value into account when determining perspiration is important.

Example. Electrodes 14 with zero resistance are designed to obtain information about the magnitude of the electrical resistance of the investigated area relative to the passive electrode 9. This is achieved as follows. Electrodes 14 with zero resistance are connected on the one hand to each other

shortly 4, these electrodes are designated as Po, RK1 is the resistance of the skin between the electrically conductive rods 14, R electric is the electrical resistance between the active electrode 8 and the passive electrode 9, the Stable Current Generator ensures the passage of a given stable current through the body surface under study the subject. The change in electrical resistance RKI between electrically conductive rods 14 with zero resistance does not affect the magnitude of the total electrical resistance (R0I). With dry skin, the RKI may be equal, for example, 5 kΩ, with the secretion of sweat, the RKI decreases and may be, for example 0.1 kΩ In both cases

Noobs - Electric power -j-.

 const

Conductive rods 13c with predetermined resistance are designed to obtain information about the magnitude of the electric-resistance (non-dermal) resistance and

perspiration. Figure 5 shows two of the electrically conductive rods 13 with a given

RL resistance

In this case, electrically conductive rods 13 with a predetermined resistance RI are interconnected, short-circuited on the one hand, and on the other hand between the points of contact with the surface of the subject's skin are areas of skin with a certain resistance R KL The resistance of the skin areas RKI will depend on perspiration. However, with dry skin, RKI can

to be, for example, 5 kΩ, with sweat secretion, RKI decreases and can be, for example, 0.1 kΩ. In this case

Total -

V2

 const

or

Total - Electric +

(Ri + RKp-Ri

2 Ri -f RKI

50 An example of the calculation of no. in specific cases: i case. Skin dry RI 10 kOhm, RKI

5 KOM, Electric skinning SO.

Roem - 100 2 ° 1oD15 10Q + 6

- 106 kΩ

N case. Skin with a secret of sweat, RI 10 kOhm

RK1 0.1 KOM, Electrical 100 kΩ.

) ° + (P 100 + 5.47

 105.47 kΩ

Thus, with an increase in sweating, a decrease in P0 total occurs, which makes it possible to determine the intensity of sweating, since There is a linear relationship between electrical conductivity and sweating intensity.

The proposed device allows simultaneous recording of Р0бщ., Reflecting the POTOOPARISON + Electrocutely through the use of electrically conductive rods 13c with a given resistance, and Ptotch, reflecting only Electroskin, through the use of electrically conductive rods 14 with zero resistance. Ph o rm a l u a r a d i n i 1. A device for the study of thermo-regulatory reactions of a person, containing a sensor that includes an active and

Passive electrodes, power supply, bridge circuit, amplifier and recorder, characterized in that, in order to increase the accuracy of the study of thermostatic

human reactions due to simultaneous recording of electrical resistance and sweating from the same area of the human body, it is equipped with a second bridge circuit and amplifier, the recorder performs two-channel, and the active electrode of the sensor contains two groups interconnected of electrically conductive rods with a predetermined and zero resistance staggered perpendicular to the working surface and connected to the appropriate bridge circuits, amplifiers and channels of the recorder.

2. The device according to claim 1, that is, in that the body of the active electrode of the sensor and the working surface are installed with a gap.

K 5leku 2

I I

1

I j m 5l ok y 3

Fig.Z Yu

FIG.

i

to,

FIG. five

Electric skin

Claims (2)

Claim 1. A device for studying human thermoregulatory reactions, comprising a sensor including active and passive electrodes, a power supply, a bridge circuit, an amplifier and a registrar, characterized in that, in order to improve the accuracy of studying human thermoregulatory reactions by simultaneously registering electrical resistance and sweating with of the same part of the human body, it is equipped with a second bridge circuit and an amplifier, the recorder is made of two channels, and the active sensor electrode contains two groups, with interconnected conductive rods with a given and zero resistance, staggered perpendicular to the working surface and connected to the corresponding bridge circuits, amplifiers and channels of the recorder. 2. Device pop. 1, distinguished by the fact that the housing of the active electrode of the sensor and the working surface are installed with a gap. Figure 1 Block 2 To blocks 2,3 Fig ¹ /