RU2492919C1 - Gas mixer with electronic control - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to gas mixers and may be used for making gas mixes used as a protective medium in welding and varying gas mix composition in operation. Proposed mixer comprises first and second gas receivers and mixing chamber. Besides the mixer comprises case to house two inlet and two outlet filters, two inlet and to outlet dispensing nozzles, two pressure gages connected to receivers and third pressure gage connected differentially between first gas receiver and mixing chamber, two inlet an two outlet valves, control board connected to pressure gages, inlet and outlet valves and to power supply. Control push buttons are arranged on the casing outer surface as well as setting indicators, inlet gas and mix discharge fittings. Inlet filters are arranged ahead of every inlet valve, one filter per one valve while outlet filters are arranged behind every receiver.

EFFECT: faster mixing, better mix homogeneity.

3 cl, 2 dwg

Description

The invention relates to gas mixers and can be used to obtain a mixture of gases used as a protective medium in welding processes, and, if necessary, to change the composition of the gas mixture during operation.

At the moment, there are a large number of mixers, which include analyzers of flow, pressure and gas concentration [1, 2]. The data obtained by the analyzers is used to control the parameters of the mixing process, such as flow rate, pressure and concentration of components in the gas mixture.

The disadvantage of such mixers is that, firstly, they have large dimensions, and secondly, the length of the control time and low accuracy of the composition of the mixture, which does not ensure the constancy of the given concentration of the components of the gas mixture when the pressure in the cylinders changes in welding production, unsatisfactorily affects the chemical composition of the weld and its properties.

Closest to the proposed device is a gas mixer [3], containing consisting of blocks, each of which includes two flow controllers, two metering chambers and one mixing chamber. The metering chambers that are sealed relative to each other are separated by a bulkhead with a soft diaphragm installed in it, against which the rods of the flow control valves of the gases entering the chambers are metered, which are metered through a wall made of alternating metal and rubber plates, in which holes are drilled, located coaxially and having the same shape, but their sizes in rubber plates are larger than in steel ones.

The disadvantage of the prototype device is the low speed of mixing gases and the heterogeneous composition of the mixture.

The objective of the invention is to increase uniformity and increase the rate of occurrence of a given finished mixture.

The problem is achieved in that in an electronically controlled gas mixer containing a receiver of a first gas, a receiver of a second gas, a mixing chamber, an additional housing and the following are installed:

- two input and two output filters;

- two input and two output dosing nozzles;

- two pressure sensors connected to the receivers, and a third pressure sensor connected differentially between the receiver of the first gas and the gas mixing chamber;

- two inlet and two outlet valves;

- control board (for analyzing signals from pressure sensors and valve control), as well as control buttons located on the outer surface of the housing, setting indicators;

- fittings for connecting the inlet gases and the outlet of the finished mixture, and the inlet filters are installed one in front of each inlet valve, and the outlet filters are installed one after each receiver, each of the inlet valves is connected to one of the inlet metering nozzles through which the first or second gas to the receiver.

At the output of each receiver, there is an output valve connected to one of the output dosing nozzles, the first and second sensors are connected respectively to the first and second receivers, and the third sensor is differentially connected between the receiver of the first gas and the mixing chamber.

The task is also achieved by the fact that in the gas mixer, the first gas is argon, and the second gas is carbon dioxide, while the volumes of the receivers for argon and carbon dioxide are in a ratio of 4: 1.

In the mixers closest to the proposed device, it is necessary to spend time on the volume of the volume in the mixing chamber, and during idle time, a gas with a higher pressure displaces the gas with a lower pressure and the first mixture is not the same that was set. Achievable technical result is the high speed of the appearance of the finished mixture and the uniformity of the given mixture is constant due to the fact that the gases in the receivers are at the same pressure and gas mixing occurs directly in the pipeline during gas transportation.

Figure 1 presents the pneumatic diagram of the proposed device, containing two input 1 and two output 2 filters, two input 3 and two output 4 valves, three sensors 5, 6, the receiver of the first gas and the receiver of the second gas 7, two input 8 and two output 9 metering nozzles, which are metering sleeves having a certain diameter of the passage opening for supplying the required amount of gases, mixing chamber 10.

Figure 2 presents the design of the proposed device, comprising a housing 11, a control board 12, a power source 13, control buttons 14, setting indicators 15, fittings for connecting the input gases and the outlet of the finished mixture 16, connecting hoses 17.

The proposed device operates as follows. Argon and carbon dioxide gases through fittings 16, inlet filters 1 and inlet dosing nozzles 8 are supplied to the receivers 7. The principle of operation is to balance the pressures of the mixed gases and pulse mixing of carbon dioxide into argon when leaving the mixing chamber 10. The control board 12 constantly monitors the state of values with sensors 5 and, under certain conditions, turns on or off the corresponding valve.

If the inlet pressure of at least one of the gases is less than 0.6 MPa, the operation of the outlet valves 4 is blocked (Requirement POT RM-020-2001, paragraph 10.3.5).

The operation of the device is to constantly equalize the pressure of the inlet gases in the receivers by opening and closing the valves. The valves receive a command from the control board depending on the signals received from the pressure sensors 5. Next, gases with equal pressures through the filters and outlet valves 4 enter the mixing chamber 10. Argon through the open outlet valve 4 and the outlet dosing nozzle 8, and carbon dioxide through the second an outlet valve 4 and a second outlet metering nozzle 8. The amount of carbon dioxide in the mixture is controlled by the opening time of the second outlet valve 4.

The start of operation of the output valves is determined by the third sensor 6, which is switched on differentially between the argon receiver 7 and the gas mixing chamber 10.

Information sources

1. DE patent No. 10125863, B01F 3/02 of November 28, 2002

2. Patent FR No. 2810260, B01F 3/02 of December 21, 2001.

3. RF patent No. 2419482, B01F 3/02 of September 30, 2009.

Claims (3)

1. An electronically controlled gas mixer containing a first gas receiver, a second gas receiver and a mixing chamber, characterized in that the housing and two inlet and two outlet filters, two inlet and two outlet metering nozzles, two a pressure sensor connected to the receivers, and a third pressure sensor connected differentially between the first gas receiver and the gas mixing chamber, two inlet and two outlet valves, a control board connected to the pressure sensors, inlet and output valves and power supply, connecting hoses, as well as control buttons located on the outer surface of the housing, setting indicators, fittings for connecting the input gases and the outlet of the finished mixture, the input filters being installed one in front of each inlet valve and the output filters are installed one after of each receiver, each of the inlet valves is connected to one of the inlet metering nozzles through which the first or second gas enters the receiver, an outlet valve is placed at the outlet of each receiver Connected to the audio output of the metering nozzle, the first and second sensors are connected to first and second receiver, and the third sensor is connected between the differential receiver of the first gas and the mixing chamber. 2. An electronically controlled gas mixer according to claim 1, characterized in that the first gas is argon and the second gas is carbon dioxide. 3. An electronically controlled gas mixer according to claim 2, characterized in that the volumes of the receivers for argon and carbon dioxide are in a ratio of 4: 1.

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