RU2830855C1 - Universal module to ensure operation of filtering gas mask in isolating mode - Google Patents

Abstract

FIELD: gas masks.

SUBSTANCE: invention relates to devices for protection against poisonous and harmful substances, in particular with individual breathing apparatus. Universal module for providing the operation of the filtering gas mask in the insulating mode comprises a housing with a cover, an inlet fitting for connection to a compressed air source connected to the inlet valve, and an operating mode switch, wherein the module is equipped with a spring-loaded drive rod, a nozzle, a spring-loaded mechanical shut-off valve, a control valve, a pneumatic lift valve, a spring-loaded outlet valve, membrane tightly fixed inside the housing and dividing the housing into a constant pressure cavity combining the spring-loaded mechanical shutoff valve and the pneumatic lift valve, and a balancing pressure cavity extending under the outlet valve seat into a channel with a nozzle above the outlet valve seat to form a control chamber and into the inlet valve channel, wherein on the cover with the housing there are coaxially located screw neck with a reed inhalation valve and a screwed neck with a cylindrical locking device of the reed valve installed in it, the inlet valve is made with a stem and a headpiece, operating mode switch is made two-position, mechanically interacting with the shut-off valve and the inlet valve tip, the spring-loaded drive rod is equipped with a thrust heel for the pneumatic lift valve and is pivotally connected with the housing of the cylindrical blocker of the reed valve and the housing, control chamber has elastic side walls, on one side are rigidly fixed along the contour in the housing, and on the other side they are connected to the outlet valve, besides, the membrane has no contact with atmosphere and mechanical connection with the control valve.

EFFECT: increased efficiency and efficiency of respiratory protection means in contaminated atmosphere, level of protection against external effects, as well as reduced weight and size characteristics.

1 cl, 4 dwg

Description

Field of technology

The invention relates to life support means, namely to devices for protection against toxic and harmful substances, in particular with individual breathing apparatus and can be used in means of protecting the respiratory organs, eyes, skin of the face and head from chemical toxic substances, as well as in conditions of insufficient oxygen in the surrounding air or the presence of high concentrations of hazardous chemicals in the air, poorly absorbed vapors of chemicals.

State of the art

As the accumulated experience of actions of rescue military formations of the civil defense forces, the Ministry of Emergency Situations of the Russian Federation and units of the radiation, chemical and biological defense troops of the Armed Forces of the Russian Federation shows ¹ (1. Maltsev S.A., Weber E.B., Inozemtsev V.A., Tsapkov M.V., Belyakov P.E., Kovtun V.A., Antokhin A.A. On the progress of implementing priority measures to eliminate the accumulated damage to the environment from the activities of chemical enterprises in the territory of Usolye-Sibirskoye, Irkutsk Region // Bulletin of the RCB defense troops. 2021. Vol. 5, No. 2. Pp. 136-148.), the most appropriate method of individual protection of rescuers is the use of isolating-filtering devices (IFD). Due to the specific nature of the activities of emergency response units, the design of the IFA must be adapted to the design of filter gas masks, have a high degree of standardization and unification with their components and parts, exclude the possibility of exposure of the internal components of the apparatus to vapors of toxic substances, have the minimum possible weight and size characteristics and ensure multiple changes in the protection mode regardless of the duration of the interruption in operation. However, to date, these technical problems have not been fully resolved.

Thus, a design of a breathing apparatus is known (RU Patent No. 2168340, IPC A62B 7/08, published in 2001), which can be used in both filtering and isolating modes of operation. The said apparatus comprises a facepiece, a regeneration unit with a starting device, a filtering and absorbing box (FAB), a distribution unit, inhalation and exhalation valves, and a gas duct equipped with a pressure relief valve and connected to the starting device and the distribution unit. The disadvantages of the design are the high weight and size characteristics of the apparatus, the possibility of spontaneous transfer of the IFA from the isolating mode of operation to the filtering mode when the pressure in the gas-emitting circuit decreases.

The possibility of spontaneous change of the protection mode was eliminated in the design of the breathing apparatus (RU Patent No. 2461398, IPC A62B 7/08, published 2012), which additionally contains a rotary cam mechanism, as well as a connecting device of the regeneration unit starter with a distribution unit in the form of a flexible rod.

The common disadvantages of the above-mentioned designs of breathing apparatus are:

- the impossibility of re-enabling the device in the isolation mode of operation without replacing the regeneration unit;

- the need to manufacture and use original face parts of the breathing apparatus, regeneration units and operating mode switching units;

- low ergonomic and operational characteristics, due to significant overall dimensions due to the use of connecting tubes and placement of the FPC regeneration unit and switching unit on the body.

The ability to repeatedly switch the IFA into the isolating mode of operation was achieved in the design of the respiratory protection unit against exposure to hazardous substances of chemical and biological nature (patent for utility model RU 195443 U1, IPC A62B 15/00, published in 2020), containing an autonomous breathing apparatus of an isolating type on compressed air with a lung machine located on the suspension system of the apparatus and connected to the face part on the right side, and a filter unit including an autonomous turbo unit and an FPC collector connected to the face part on the left side by means of a connecting tube. However, the disadvantages that determine the need to manufacture and use original components of the apparatus, the use of a standard lung machine having a connection of the outer side of the membrane with air contaminated with vapors of toxic substances, as well as significant weight and size characteristics in the proposed design are not eliminated.

The closest in technical essence to the claimed invention is the design of a breathing apparatus (patent WO 2011136674, published 2011), containing a source of compressed gas, a mask with a valve box and an exhalation valve, a lung demand valve consisting of a housing with an inlet nozzle, a cover, a membrane hermetically installed between the housing and the cover, an inlet valve installed in the housing to form a control chamber, the outlet of which is made in the form of an inlet valve seat, a control valve interacting with the inlet valve seat. The said design of the breathing apparatus provides for a reduction in breathing resistance due to a reduction in the response time of the lung demand valve, the ability to connect the lung demand valve to a standard face part both to ensure the possibility of operation in an isolating mode and for breathing from the atmosphere without disconnecting the elements of the apparatus from the body of the face part.

The main disadvantages of the prototype are:

the membrane is not protected from the effects of chemically hazardous substances, which makes it possible for them to penetrate into the respiratory circuit;

- the impossibility of using the FPC to clean the air after completing work in full isolation mode.

Disclosure of invention

The objective (technical problem) of the proposed invention is to create a small-sized device that provides the possibility of using a filter gas mask in an isolating mode of operation using a source of compressed air and allows for an increase in the level of ergonomic and operational properties, the efficiency of use for its intended purpose and the elimination of the impact of chemically hazardous substances on the internal elements of the device.

The technical result using the proposed invention is achieved in that between the small-sized FPC and the face part of the filter gas mask, a universal module is installed, including a housing with a lid with a screw-on neck with a petal inhalation valve and a screw-on neck with a cylindrical petal valve lock installed in it, an inlet fitting for connecting to a compressed air source connected to an inlet valve with a rod and a tip, a spring-loaded outlet valve, a membrane hermetically secured inside the housing and dividing the housing into a constant pressure cavity combining a spring-loaded mechanical shut-off valve and a pneumatic lifting valve, and a pressure equalizing cavity exiting under the seat of the outlet valve, into a channel with a nozzle above the seat of the outlet valve to form a control chamber and into the channel of the inlet valve, a control valve, a two-position switch mechanically interacting with the shut-off a low-pressure cavity valve and an inlet valve tip, a spring-loaded drive rod, pivotally connected at the ends to the body of the cylindrical petal valve lock and the body and having a stop heel for a pneumatic lifting valve, characterized in that the membrane has no contact with the atmosphere and no mechanical connection with the control valve, the control chamber has elastic side walls, rigidly fixed on one side along the contour in the body, and connected on the other side to the outlet valve.

The universal module is a three-dimensional product of flat oval shape, the maximum dimensions of which in length, width and height do not exceed 125 mm, 115 mm and 55 mm, respectively. In the internal volume of the body and cover, parts of units are molded to accommodate the actuators of the universal module. When the cover and the body are connected, closed circuits are formed that have no connection with the external environment, through which controlled air supply to the respiratory organs is carried out.

The body, cover and internal elements are made of plastic, the membrane and side walls of the control chamber are made of rubber, silicone or latex. The necks have standard threads according to GOST 8762-75. The maximum excess pressure formed in the body cavities does not exceed 3000 Pa. Sealing of the cover along the contour of the body, membrane, necks is carried out by using rubber gaskets and rings.

The membrane, hermetically secured in the housing, has a mechanical connection with the inlet valve due to the effect on the tip of the stem during deflection.

The design of the control chamber of the universal module has side walls made of elastic material, which bend outward during the inhalation phase before the opening of the control valve. Due to the longitudinal elasticity of the walls of the control chamber, the pressing force of the spring of the outlet valve is weakened and air begins to flow through the seat of the outlet valve during inhalation, thereby reducing the response time of the membrane rise and reducing resistance to inhalation.

The cut-off of outside air during operation in the full isolation mode is ensured by a petal valve installed on the screw neck and a cylindrical blocker interacting with it. The use of a petal valve, unlike a solid valve, practically does not provide additional resistance to the air flow and provides the ability to cut off the internal volume of the module from the environment by pressing only the edge of the valve to the seat.

The cylindrical blocker is made in the form of a perforated cylinder without end faces, placed in the internal cavity of the screw neck and simultaneously serving as a guide sleeve when the blocker moves.

The change in the position of the blocker depending on the internal pressure in the cavity of the universal module housing is ensured by a rod driven by a lifting valve.

Thus, the specified features of the proposed universal module for ensuring the operation of a filter gas mask in an isolating mode form a set of essential features necessary for achieving a technical result consisting in ensuring the possibility of using a filter gas mask in an isolating mode of operation using a source of compressed air with a simultaneous significant reduction in weight and size characteristics.

Brief description of the drawings

Fig. 1 shows the arrangement of the universal module on the gas mask; Fig. 2 shows the universal module in the filter mode; Fig. 3 shows the universal module when starting the isolation mode; Fig. 4 shows the universal module in the inhalation phase in the isolation mode. Implementation of the invention

The universal module for ensuring operation of the filter gas mask in the isolation mode 7 is screwed with a screw-on neck 21 into the mating socket of the gas mask 2. A small-sized filter-absorbing box 4 from the gas mask kit is screwed into the screw-on neck 3, and a reduced-pressure hose is connected to the nipple 5 and a shut-off valve from a compressed air source is opened (not shown in the figure). The universal module is in the "filtration" mode and is ready to be transferred to the "isolation" mode.

In the filtering mode, the petal inhalation valve 6 is held in the center of the seat of the screw neck 3, located in the cover 27, by a molded pin. The inlet valve 7 is locked by the pressure of the reduced air. The membrane 8, hermetically secured in the housing 29, is in the middle position, the shut-off valve of the constant pressure line 9 and the outlet valve 11 are closed due to the forces of the support springs 10 and 12. In the inhalation phase, the vacuum formed in front of the petal valve 6 tears its peripheral part away from the seat of the neck 3 and the purified air enters the respiratory organs. The control valve 14 is held in the closed position by the force of the support spring 13.

To start the universal module in the isolation mode, it is necessary to successively turn the two-position switch 15 to the fixed position "1", and then briefly to the free position "2". In the fixed position "1", the two-position switch 15, by moving the rod, slightly opens the shut-off valve 9 without changing the states of the other elements. A short-term transfer of the two-position switch 15 to the free position "2" due to the mechanical action of the pusher 17 on the nozzle 19 shifts the rod 18 of the inlet valve 7 along the surface of the membrane 8 and opens access of reduced air to the internal cavities of the module. After returning the two-position switch 15 to the fixed position "1", the inlet valve 7 is locked under the action of the reduced air pressure, the rod 18 with the nozzle 19 return to the original position, and the shut-off valve 9 remains in the open position. In this position, excess pressure equal to the opening pressure of control valve 14 is created in the cavities of the housing: air with reduced pressure opens outlet valve 11 and is released through air duct openings 20 into the front part through the opening of neck 21, and part of the air entering through the channel with nozzle 28 into the cavity behind the outlet valve, through control valve 14 is also released into the front part through the opening of neck 21. At the same time, the reduced air entering the internal cavity acts on lifting valve 22, which, acting on stop heel 23, lifts rod 24 together with cylindrical blocker 25, locking petal valve 6. Returning two-position switch 15 to its original position leads to locking valve 9 and isolation of the constant pressure cavity, limited by the inner sides of membrane 8, shut-off valve 9 and lifting valve 22, from cavity equalizing pressure, limited by the outer sides of the membrane 8, inlet 7, outlet 11 and control 14 valves.

In the inhalation phase in the isolating mode, due to the vacuum that is formed, the elastic walls 26 of the control chamber begin to bend outward and reduce the pressing force of the spring 12. At the same time, the control valve 14 opens, air flows out of the volume of the control chamber and the outlet valve 11 opens. Since the flow section of the nozzle 28 is significantly smaller than the flow section of the control valve 14, then throughout the inhalation phase, a vacuum is maintained in the control chamber and the outlet valve 11 remains open. Air from the equalizing pressure cavity through the outlet valve 11, air duct openings 20 begins to flow for inhalation and the pressure in the cavity decreases. Due to the difference in pressure in the constant and equalizing pressure cavities, the membrane 8 rises, which mechanically shifts the rod 18 and opens the inlet valve 7.

During the breath-holding and exhalation phases in the isolation mode, there is no vacuum inside the housing and the control valve 14 closes under the action of the spring 13. The air entering through the inlet valve 7 continues to pass into the free volume of the housing through the outlet valve 11 and the air duct openings 20. Due to part of the air passing through the nozzle 28, the pressure in the control chamber increases, equal to the opening pressure of the control valve 14, the outlet valve 11 begins to close, reducing the volumetric speed of the air outflow, and the pressure in the pressure equalization cavity increases. The increase in pressure leads to the lowering of the membrane 8 and the inlet valve 7 is locked. The air outflow through the outlet valve 11 and the air duct openings 20 is completed when the initial value of the excess pressure in the pressure equalization cavity is reached and the pneumatic system goes into the initial static position.

To switch off the isolation mode, it is necessary to move the two-position switch 15 to the fixed position "1". In this case, the two-position switch 15 slightly opens the shut-off valve 9 by moving the rod, and the air contained in it is released from the constant pressure cavity. In the absence of excess pressure, the rod 24 returns to its original position, the blocker 25 is lowered and the operation of the petal inhalation valve in the filter mode is resumed.

This design differs from existing devices of IFA actuators by its versatility, low weight and size characteristics, high adaptability to the design of filter gas masks and speed of use, and eliminates the possibility of exposure of internal elements to chemical toxic vapors.

Claims (1)

A universal module for ensuring the operation of a filter gas mask in an isolating mode, comprising a housing with a cover, an inlet fitting for connection to a source of compressed air, connected to an inlet valve, and an operating mode switch, characterized in that it is equipped with a spring-loaded drive rod, a nozzle, a spring-loaded mechanical shut-off valve, a control valve, a pneumatic lift valve, a spring-loaded outlet valve, a membrane hermetically secured inside the housing and dividing the housing into a constant-pressure cavity combining a spring-loaded mechanical shut-off valve and a pneumatic lift valve, and a pressure-equalizing cavity extending under the seat of the outlet valve into a channel with a nozzle above the seat of the outlet valve to form a control chamber and into the channel of the inlet valve, wherein a screw-in neck with a petal inhalation valve and a screw-in neck are coaxially located on the cover with the housing with a cylindrical petal valve lock installed in it, the inlet valve is made with a rod and a nozzle, the operating mode switch is made two-position, mechanically interacting with the shut-off valve and the tip of the inlet valve, the spring-loaded drive rod is equipped with a stop heel for the pneumatic lifting valve and is pivotally connected at the ends to the body of the cylindrical petal valve lock and the body, the control chamber has elastic side walls, on one side rigidly fixed along the contour in the body, and on the other side connected to the outlet valve, wherein the membrane has no contact with the atmosphere and mechanical connection with the control valve.