SU1254312A1 - Vibration dosimeter - Google Patents

Abstract

The invention relates to a measurement technique and can be used to control the average vibration load on a person (operator) over a long period of time. The aim of the invention is to measure the accumulated dose of vibration, its exposure time (control time) and the biological effect of the vibrating dose, defined as the rms value of the vibrating dose during the monitoring. The vibration meter contains two recording units, made on the basis of a capillary with a porous septum, filled with a polar liquid, and placed on opposite sides of the septum of the electrodes. A mercury droplet is placed in the cavity of the capillaries, providing visual control of the volume of the polar fluid that has flowed through the porous septum under the influence of the EMF applied to the electrodes. One recording node is connected to a DC source. The amount of movement of a mercury droplet in this recording unit is proportional to the monitoring time. Another recording node is connected to a vibration intensity converter into an electrical signal. His readings characterize the accumulated dose of vibration. The biological effect is calculated using functional and logarithmic scales installed along the capillaries of the recording sites. 3 il. (/)

Description

The invention relates to a measurement technique and can be used to monitor the accumulated dose of vibration, the time it is monitored and to evaluate the biological effect of the dose of vibration.

The aim of the invention is to provide the possibility of automatically measuring the biological effect of a dose of vibration by simultaneously controlling the accumulated dose and the time of exposure to vibration.

FIG. 1 shows the structure, vibration meter, slitJ in FIG. 2 - view of it from the side of reading scales; in fig. 3 shows a capillary registering unit.

The vibration meter contains a housing 1, a capillary registering unit 2 placed on it, a constant current source 3 and a limbus 4 connected to it with scales 5, 6 and 7 applied on its surface to control and functionly convert the parameter — time of vibration. In the central part of the housing 1, a board 8 is installed coaxially with the recording unit 2 and rotatably with respect to the housing 1. In the cavity of the board 8, a vibration converter 9 is placed into an electrical signal, made, for example, in the form of a piezoelectric element. On the surface of the board 8 is fixed coaxially with the recording unit 2 and in the same plane with it a limb 10 with a second recording unit 11 fixed on it, designed to control the accumulated dose of vibration. On its surface are readout scales 12 and 13, designed to control and functionally convert the parameter accumulated

dose of vibration.

Capillary recording units 2 and 10 are made in the form of a container with attached to it are the ends of a transparent tubular capillary 14. Mercury is placed in the capillary cavity

droplet 15, and inside the vessel a porous partition 16 is installed, along the surface of which mesh electrodes 17 are placed, intended to connect a source of direct current 3. Rinse the tank and capillary 14 filled with polar current-carrying fluid 18.

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The porous partition 16 can be made, for example, from glass or porcelain. The thickness of the porous septum is 16. 3 mm, the porosity is 25%, the electrical resistance is 2–10 ohms, the pore diameter is 1 μm, and the internal diameter of the capillary is 14 or less than 3 mm. The hydraulic pressure developed along the capillary 14, under these conditions, is rather high compared with the external mechanical action, which ensures the stability of the recording unit to the effects of vibration. To further increase mechanical stability, the inner surface of the capillary 14 is covered with a thin transparent film of an organic polymer, not wettable with a polar liquid.

The vibration-to-electrical signal converter 9 is connected to the recording node 11 via a rectifying diode. As a transducer 9, a piezoelectric element or an electret can be used, providing an operating current in the order of 0.01-200 μA with an ohmic load resistance of about 2-10 ohms.

The vibration meter works as follows.

Before starting the measurements, the vibration meter is mounted on the monitored object, after which the direct current source 3 is turned on. Under the interaction of direct current flowing through the polar liquid 18 between the grid electrodes 17 of the recording unit 2, designed to control time, the polar liquid flows through the porous wall 16. This causes the liquid to flow also in the capillary 14 and, consequently, mercury droplets 15. The amount of movement of a mercury droplet is proportional to the amount of electricity flowing between the grid electrodes 17. Since the current through the electrodes of the recording unit 2 is connected nym them source 3 DC unchangeable in time, the movement of the mercury drop in the registering node proportional control time (exposure time of vibration).

When exposed to vibration converter 9 vibration to electric

The signal produces an emf proportional to the square of the intensity of the vibration. After straightening with the help of a diode, the emf generated by the transducer 9 is applied to the grid electrodes 17 of the recording unit 11, which causes a mercury drop to move in its capillary, which is proportional to the accumulated dose of vibration. The accumulated dose I) of vibration and time T of its action, respectively, are determined from the magnitudes of movement of the mercury drops of the recording units 2 and 11, visually observed by the operator | and measured on scales 13 and 5.

The root-mean-square equivalent value of E vibration can be determined by the formula

The e-B calculations using this formula are implemented using scales 6 and 12 of the computing device, performing the transformations vT and tF, respectively, and the logarithmic scale 7. The procedure for calculating the biological effect is a known procedure for calculating with a slide rule.

Measurement of the biological effect of the accumulated dose of vibration allows an objective assessment of the vibration load on the monitored object (person) for a long time.

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Claims (1)

Invention Formula A vibration meter containing a transducer of vibration into an electrical signal, a capillary recording unit connected to it, made in the form of a container filled with a polar liquid, which divides it into two parts; a porous septum attached by ends to a container on opposite sides of the septum of a transparent tubular capillary with a mercury drop and installed on the sides of the septum of two mesh electrodes, which is characterized by the fact that, in order to measure the biological effect of the dose of vibration by simultaneously: controlling T the accumulated dose and time of vibration, it is equipped with a second capillary recording unit, similar to the first recording unit, connected. to it for the time being monitored by a source of direct current and a computing device, made in the form of two established with the possibility of mutual movement of the limbs from countable scales, on each of which one of the capillary recording units is fixed. (roe. 7 rj 12 Fick. 2 Editor A.Gulko Compiled by I. Kislycin Tehred M. Khodanych Order 4710/44 Circulation 507Subscribe VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Raushsk nab. D. 4/5 Production and printing company, Uzhgorod, st. Project, 4 py ".J Proofreader M.Sharoshi