SU1648490A1 - Respiratory gas mixer - Google Patents

Abstract

This invention relates to a medical technology for mixing respiratory gases. To improve the accuracy of gas mixture preparation, the respiratory gas mixer contains sources 1 and 2 of compressed gases, adjustable throttles 3 and 4, flow indicators 5 and 6, pressure equalizer 7, pneumatic throttle elements 9 and 10, mixing chamber 11, thermostat 12. 1 Il.

Description

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This invention relates to a medical technology for mixing respiratory gases.

The aim of the invention is to improve the accuracy of the preparation of the gas mixture.

The drawing shows a schematic diagram of the mixer of respiratory gases.

The respiratory gas mixer contains sources 1 and 2 of various compressed component gases of the prepared mixture, adjustable chokes 3 and 4, flow indicators 5 and 6, the outputs of which are connected to the inputs of the equalizer 7 pressure, which through an adjustable choke 8 is connected to the line of atmospheric discharge, pneumatic throttle elements 9 and 10, the inputs of which are connected to the inputs of the equalizer 7 pressure, and the outputs to the inputs of the chamber 11 of the mixing of gases. All elements of the mixer, except for sources 1 and 2 of compressed gases, are placed in a thermostat 12.

The throttle elements 9 and 10 are capillary tubes. The pressure equalizer 7 and the gas mixing chamber 11 are, in the simplest case, tees. To reduce the likelihood of gas flowing in start-up modes from one line to another, the input channels of such a tee are made at an acute angle to each other.

As indicators 5 and 6 can be

rotometric indicators are applied

flow or heat flow meters. They are set to determine flow.

gas in each channel of the mixer.

The mixer works as follows.

The compressed gas streams from sources 1 and 2 through adjustable throttles 3 and 4 and flow indicators 5 and 6 are branched to pressure equalizer 7 and capillary tubes 9 and 10. The mixture of gases from the output of pressure equalizer 7 is discharged through adjustable throttle 8. From the output of capillaries tubes 9 and 1t) the components of the gas mixture enter the gas mixing chamber 11, and then the mixture obtained goes to the consumer. By means of adjustable chokes 3 and 4, as well as throttles 8, the mixer is adjusted, the amount of the mixture delivered to the consumer, as well as the pressure at the inlets of the capillary tubes are adjusted.

Compiled by A.

Claims (1)

The mixer compensates for the effects of pressure changes at the inlets and outlets of the capillary tubes 9 and 10, as well as the barometric pressure, and thereby improves the accuracy of gas mixture preparation. For example; Increasing the pressure of one component at the inlet of the mixer leads to an increase in pressure at the inlets of the capillary tubes 9 and 10, while the pressure at the inlets of them is the same, although a bit more. The increase in pressure at the inlets of the capillary tubes 9 and 10 causes a corresponding increase in the flow rates of each component, but the geometrical parameters 5 of the capillary tubes 9 and 10 are selected so that the increase in the flow rates of both components is proportional and therefore the concentration of the mixture components at the mixer exit remains the same. 0 claims A respiratory gas mixer containing a thermostat, a mixing chamber and gas channels, including each source of compressed gas and a pneumatic choke, 5 is characterized in that, in order to improve the accuracy of gas mixture preparation, it is equipped with an adjustable choke and flow indicator, sequentially installed in each 0 gas channel between the compressed gas source and the pneumatic throttle element, a pressure equalizer with inlets connected between the pneumatic throttle elements inlets and a single inlet - 5 house, as well as adjustable throttle reset connected to the output pressure equalizer and pneumatic throttle elements are designed as capillary tubes, the design parameters which are determined depending E 0 №P where ti, fe are the lengths of the capillary tubes of the first and second gas channels; 5di, da - diameters of capillary tubes; / Mt, / W2 - dynamic viscosity first and second mixed gases; 0Ri, Ra - gas constant gases; P, ha - given mass concentration of gases. adaev Editor I. Gorna Tehred M. Morgenthal Order 1476 Circulation 398 Subscription VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, 4/5 Raushsk nab. Proofreader M. Sharoshi