JP2022055856A - Gas joint for flashback prevention - Google Patents

Abstract

To provide a gas joint for flashback prevention having a function for preventing expansion of fire spread, even if conduit means for oxygen supply is ignited.SOLUTION: A gas joint for flashback prevention includes a joint body having a gas passage inside, a valving element movable in the joint body, and two compression springs for holding the valving element on a position where gas flow is possible in the compressed state from both direction to the gas flow. One end of the compression spring is fixed on a gas passage inlet part of the joint body, and a seal surface for blocking gas flow is provided on a gas passage inner surface.SELECTED DRAWING: Figure 1

Description

The present invention is connected to a flexible conduit such as an oxygen cylinder, a nasal cannula for supplying a flammable breathing gas such as oxygen gas supplied from liquid oxygen or oxygen concentrating gas from an oxygen concentrator, and is near the fire source. Provided is a gas joint having a function of ignition through a conduit, prevention of flashback to prevent extension of flame, and oxygen gas shutoff function when used in.

Conventionally, oxygen inhalation therapy that supplies oxygen gas and oxygen-concentrated air via an oxygen cylinder, a liquid oxygen container, and an adsorption-type oxygen concentrator that separates oxygen in the air has been performed for patients with respiratory diseases, especially aftereffects of tuberculosis. It is widely used as a home treatment method for patients with chronic respiratory diseases such as lung emphysema and COPD. Furthermore, oxygen inhalation therapy is also expected as artificial respiration management in the treatment of new coronavirus infection (COVID-19). In these home oxygen therapies, a nasal cannula or a nasal mask is used to supply oxygen or oxygen-enriched air to the patient's nasal cavity, and a soft conduit is extended from the oxygen outlet of the oxygen concentrator or oxygen cylinder to the nasal cavity. used.

Oxygen gas itself is not flammable, but it is flammable, so as a means to prevent accidents such as ignition of the extension tube and causing a fire, a metal joint is provided in the middle of the tube that supplies oxygen gas, and the tube A method of blocking the spread of a flame that ignited in a nonflammable metal joint (Japanese Patent Laid-Open No. 2006-280470), a joint provided with an opening / closing fastener for a valve that melts by heat is provided in the middle of the tube, and the fastener is fastened by the spread of fire. Disclosed is a method (Japanese Patent Laid-Open No. 2015-524697) in which the oxygen gas flow path is blocked and the spread of fire is blocked by the removal of the gas.

Japanese Unexamined Patent Publication No. 2006-280470 Special Table 2015-524697

It is an object of the present invention to provide a flashback prevention gas joint having a function of preventing the spread of fire even when an oxygen supply conduit means is ignited, and a breathing gas supply device using the gas joint. It is supposed to be. In particular, when the user moves indoors, the tube that supplies oxygen is prevented from being caught on furniture or the like when being routed, and the tube is prevented from bending, and an inexpensive, lightweight, and compact joint member that can be replaced regularly is provided.

As a result of diligent research to achieve such an object, the present inventors have obtained the compressive force of the compression spring by melting or burning the gas flow path inlet portion of the joint body due to the fire propagation from the flexible conduit. We found a gas joint that shuts off the oxygen gas flow path by opening it to the outside and pressing the valve body toward the flame propagation side.

That is, the present invention is a flashback prevention gas joint connected to a flexible conduit that supplies oxygen gas, and has a joint body having a gas flow path inside and a valve body that can move within the joint body. The valve body is provided with two compression springs that hold the valve body in a position where the gas flow is possible in a state of being compressed from both directions with respect to the gas flow, and one end of the compression spring is a gas flow path inlet portion of the joint body. The compression force of the compression spring is released to the outside by melting or burning the gas flow path inlet portion of the joint body due to the fire propagation from the flexible conduit, and the valve body is flamed by the other compression spring. Provided is a flashback prevention gas joint characterized by having a sealing surface on the inner surface of the gas flow path of the joint body for blocking gas flow by being pressed against the propagation side.

Further, in the present invention, the joint body is a molded body using a flame-retardant resin material, and the valve body is symmetrical such as a sphere or a bicone so as to block bidirectional gas flow, and is made of steel. Provided is a gas joint for preventing flashback, which is a sphere or an elastic body.

When a flashback occurs in the oxygen supply tube, the supply of oxygen gas is surely cut off to prevent burning, and the simple structure with a small number of inexpensive parts and components makes it compact, lightweight, and has a high space-saving effect. , Anti-reverse fittings can be provided. Further, by reducing the number of component parts, it is possible to provide a low-cost flashback prevention joint.
In addition, due to the miniaturization by this method, it is possible to provide a fire spread prevention joint that is less likely to get caught even when the joint is used and does not hinder the movement of the user.

The external view of the gas joint for flashback prevention of this invention. Sectional drawing of the gas joint for flashback prevention of this invention. Schematic diagram of a cross section of the gas joint for preventing flashback of the present invention when the gas is shut off. FIG. 6 is a cross-sectional view of another aspect of the gas joint for preventing flashback of the present invention. A bicone-shaped valve body used in the gas joint for preventing flashback of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. A common reference code is attached to the corresponding components throughout the drawings.

FIG. 1 shows an external view of a flashback prevention gas joint which is one of the embodiments of the present invention. The shape is a so-called bamboo-shaped tube joint at both ends, and it is used as a joint in the middle of a soft cannula such as vinyl chloride used when a patient with respiratory disease inhales oxygen gas from an oxygen concentrator or an oxygen cylinder.

When the cannula is ignited during oxygen supply, a flame of about 20 cm is instantly ejected, and the oxygen acts as a combustion improver, so that the flame goes back to the oxygen concentrator side along the cannula. The present invention can block the spread of fire in the cannula by shutting off the flame and oxygen supply at the joint portion, and can prevent the subsequent spread of fire to the oxygen concentrator side. In the case of a joint made of a flammable material, it is preferable to use a flame-retardant or self-extinguishing resin material because the ignition on the surface of the joint may ignite the cannula on the oxygen concentrator side as it is. .. For example, a fluororesin or the like having a high melting point and difficult to burn even under high concentration oxygen is preferable, and a self-extinguishing resin such as polycarbonate, nylon or vinyl chloride resin can be used. Further, a resin material to which various flame-retardant materials such as antimony-based (Sb2O3), molybdenum-based (MoO2), phosphorus-based, and intomescent-based (APP / EPR) can be used.

A non-combustible material such as a metal material can be used as the joint material, but there is a risk that the tip of the joint will burn or melt and the function of opening the compression spring to the outside cannot be fulfilled, so that the material or tip can be melted or burned. It is necessary to design the thickness of the spring in detail.

FIG. 2 shows a cross-sectional view of the gas joint for preventing flashback of the present invention. The joint bodies 2 and 3 are composed of two molded products on the left and right, and are configured by joining the two in the center. Inside, an oxygen flow path for circulating oxygen gas is provided, compression springs 1, 1'are provided on both ends of the joint, and the valve body 5 is supported by two compression springs at the center of the joint.

The valve body 5 is preferably symmetrical in shape so as to block the flow from both directions, and may be a spherical shape as shown in FIG. 2, a disk-shaped movable valve body shown in FIG. 4, or a bicone shape shown in FIG. .. The valve body is pushed from both sides by a compression spring having the same compressive force inside the joint, and is held inside the joint without blocking the flow path. Further, the left and right portions inside the joint in which the compression spring is enclosed and the central portion of the joint in which the valve body is enclosed also form a flow path through which oxygen can flow to and from the joint body.

When the combustion flame propagates from either one of the joints, as shown in Fig. 3, the resin wall supporting the spring at the tip of the joint softens or disappears due to heat, and the spring on the flame propagation side loses its support. The compressive force is lost by being pushed out from the tip of the joint, the valve body is pressed against the sealing surface of the sealing material 4 by the spring on the opposite side, and the gas is shut off.

For the valve body 5, a metal seal using a steel ball or the like is used if the sealing surface with the oxygen gas flow path of the joint can be sealed with high accuracy. Further, when the surface roughness of the sealing surface is large and it is difficult to obtain sealing accuracy, a valve body using an elastic body may be used.

As the compression spring that supports the valve body, a metal spring such as a round wire coil spring that can be stored in the oxygen gas flow path of the joint can be used. It is preferable that the tip of the compression spring is supported not in the middle of the flow path of the joint but at the tip of the joint. It is possible to shut off and prevent the spread of combustion to the joint.

Therefore, although it is necessary to maintain the force of the compression spring, the thickness of the resin molded body at the tip of the joint is preferably as thin as possible, preferably 2 mm or less, and preferably 1 mm or less.

The joint body has a symmetrical shape, and the structure is integrated by pushing and connecting two parts in the center. By pushing and connecting the joint body while supporting the valve body with the tip of the spring, the center of the valve body by the compression spring. It can take a holding structure. As a result, the diameter is small, and the number of parts can be composed of 5 parts, 2 parts for the joint body, 2 compression springs, and 1 valve body. Since it can be composed of small parts, furniture etc. can be used when handling the cannula. It is possible to provide an anti-reverse joint that is compact, lightweight, has a high space-saving effect, and does not get in the way such as being caught in the furniture.

1, 1'Compression spring 2 Joint body molded body 3 Joint body molded body 4 Sealing material 5 Valve body (sphere)

Claims (6)

A gas joint for preventing flashback that is connected to a flexible conduit that supplies oxygen gas, and has a joint body having a gas flow path inside, a valve body that can move within the joint body, and the valve body. It is equipped with two compression springs that hold the gas flow in a position where it can flow while being compressed from both directions.
One end of the compression spring is fixed at the gas flow path inlet portion of the joint body, and is fixed.
A gas joint for preventing flashback, characterized in that a sealing surface for blocking gas flow is provided on the inner surface of the gas flow path of the joint body. The gas joint for preventing flashback according to claim 1, wherein the joint body is a molded body using a flame-retardant or self-extinguishing resin material. The gas joint for preventing flashback according to claim 1, wherein the valve body is symmetrical. The gas joint for preventing flashback according to claim 3, wherein the valve body has a spherical shape or a bicone shape. The gas joint for preventing flashback according to claim 3, wherein the valve body is a steel ball or an elastic body. The gas joint for preventing flashback according to claim 1, wherein the valve body is held by a nonflammable elastic body without coming into contact with the joint body.

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