JPH04218173A - Air breather - Google Patents

Abstract

PURPOSE:To prevent air from useless supply and enable simple sure confirmation of the residue of pressurized air by reducing the pressure of the supplied pressurized air to that slightly higher than the ambient pressure and operate an alarm when supply pressure is reduced to a predetermined value or less. CONSTITUTION:A case 1 is provided which has on one end a connecting port 2 connected to a pressurized air supply source and on the other end an outlet 4 for ejecting air which a user breathes. The case 1 is formed therein with a path 5 affording communication between the connecting port 2 and outlet 4. Further are provided a pressure-reducing valve 6 for reducing the pressure of supplied pressurized air to predetermined pressure slightly higher than that outside the case 1 and a relief valve 7 for opening and closing the path 5 between the pressure-reducing valve 6 and outlet 4 to be opened and closed when the user sucks air in the path 5 from the outlet 4. Further, are provided an air pressure switch 9 for detecting the pressure of the pressurized air supplied to the connecting port 2 to be changed over between the opening and closing states by predetermined alarming pressure and a residual pressure alarm 10 connected to the air pressure switch 9 to be operated under the alarming pressure or less.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to air respirators, and in particular, the present invention has a simple configuration that prevents wasted air supply, and allows the user to easily and reliably adjust the supply air pressure of the pressurized air supply source. Regarding air respirators that allow you to check for a decrease in air intake.

0002

[Prior Art] Air respirators are used by connecting to a pressurized air supply source for diving, first aid for injured persons, breathing in oxygen-deficient atmospheres such as firegrounds, etc., and are provided with a mouthpiece that the user holds in their mouth. There are two types: one type and a mask type type that includes a mask that covers the user's nose and mouth. Mouthpiece type air respirators are used when the user can hold the mouthpiece in their mouth, and are used, for example, when diving or when the user can evacuate on their own. Mask-type air respirators are used in other cases, such as when giving breathing breath to a sick or injured person who cannot hold an air respirator on their own, or when it is difficult to maintain an air respirator due to rescue, firefighting, or other work. Ru.

By the way, some conventional air respirators include:
There is a configuration in which a small air cylinder is screwed directly into the case of an air breathing apparatus. In this type of air respirator, a pressure regulating valve that opens only when the user inhales air is interposed in the passage between the connection port for connecting the air cylinder and the outlet in the mouthpiece. Also,
The air cylinders used in this type of air breathing apparatus include those equipped with an outlet valve, and those that are opened by piercing one end wall of the air cylinder with a pin provided on the air breathing apparatus.

[0004] Furthermore, when using an air respirator, if the supply pressure of the pressurized air supply source falls below a predetermined value, there is a risk of brain damage or neurological damage due to lack of oxygen, and in extreme cases, loss of life. There is also a problem. Therefore, when using an air respirator, it is essential to confirm that the air supply pressure to the air respirator is equal to or higher than a predetermined value.

Therefore, conventionally, a pressure gauge for displaying the supply pressure is connected to the outlet valve of the air cylinder serving as the pressurized air supply source or the tip of the pressurized air piping, and the pressure gauge is used to indicate the supply pressure before use. A warning is displayed to ensure that the value is greater than or equal to a predetermined value. In addition, such pressure gauges are often connected directly to the outlet valve or tip plug, but in the case of air cylinders for diving, for example, the pressure gauge is connected to the outlet valve through a hose of about 1 m. There is.

[0007]

[Problems to be Solved by the Invention] In the conventional air respirator described above, when the user inhales air, the pressure regulating valve is opened, and pressurized air is supplied from the pressurized air supply source to the inside of the mouthpiece or mask. Air is supplied to the outlet formed in the outlet, and air at a relatively high pressure is supplied to the outlet for a short period of time, resulting in excess air being supplied. This excess air is wastefully discharged into the surroundings in order to return the internal pressure of the discharge port to normal pressure. As a result, problems arise, such as an increased burden on the air pressurization device of the pressurized air supply source and a shortened usage time of the air cylinder.

If the tip or outlet valve of the pressurized air supply source connected to the air breathing apparatus is configured to adjust the supply pressure, the tip or outlet valve is operated to adjust the supply pressure to the air breathing device. By reducing the pressure to near the pressure outside the container, it is possible to prevent the wasteful use of pressurized air as described above. Whether it can be done depends on the time and
It is also technically questionable. In addition, if the air respirator is configured to open the air cylinder by piercing one end wall of the air cylinder with a pin, it is not possible to even adjust the supply pressure in this way, and there is no way to prevent wasteful use of pressurized air. Can not.

[0009] The invention of claim 1 has been made in view of the above-mentioned circumstances, and aims to provide an air respirator that can prevent such wasteful use of pressurized air. Yes, and the invention of claim 2 is based on the air respirator according to the invention of claim 1, and further aims to provide an air respirator that has a simpler configuration by reducing the number of parts. That is.

[0010]Also, the supply pressure of pressurized air must be checked while using the air respirator, but if the pressure gauge is connected directly to the pressurized air supply source, the user of the air respirator It may be difficult to check the supply pressure during use. That is, for example, when a user carries an air cylinder as a pressurized air supply source, the user cannot see the pressure gauge unless the user takes the trouble to take the air cylinder down from his or her back. Furthermore, the pressure indicated by the pressure gauge connected to the tip of the pressurized air supply pipe cannot be confirmed from a distance. Furthermore, in the case of an air cylinder equipped with a pressure gauge connected to the outlet valve via a hose, such as an air cylinder for diving, the user can grasp and view the pressure gauge underwater;
In order to see the pressure gauge, it is necessary to search for and grab the pressure gauge floating in the water, and while the user is unaware of the air supply, the supply pressure of pressurized air decreases and there is a risk of oxygen deficiency. There is.

The invention of claim 4 has been made in view of the above-mentioned circumstances, and provides an air respirator that allows the user to easily and reliably recognize a decrease in the supply pressure of pressurized air. Claim 3
The invention is based on the air respirator according to the invention of claim 1 or 2, and furthermore, similarly to the invention of claim 4, a user can easily and reliably reduce the supply pressure of pressurized air. The object is to provide a recognizable air breathing apparatus.

0012

[Means for Solving the Problems] In order to achieve the above object, the air respirator according to the invention of claim 1 has a pressurized air supply source connected to one end thereof, as shown in FIG. 1, for example. a case 1 having a connection port 2 and a discharge port 4 at the other end for discharging air for a user to breathe; a passage 5 formed within the case 1 and communicating the connection port 2 with the discharge port 4; , a pressure reducing valve 6 which is incorporated in the case 1 and reduces the pressure of the pressurized air supplied to the connection port 2 to a predetermined pressure slightly higher than the pressure outside the case 1; and the pressure reducing valve 6 and the discharge port 4. a pressure regulating valve 7 that opens and closes the passage 5 between the
It is characterized by having the following.

[0013] Furthermore, an air respirator according to the invention of claim 2 is provided, for example, as shown in FIG. A portion 61c of the pressure reducing valve case 61
is thrust into the pressure regulating valve case 71, and a valve seat 72 of the pressure regulating valve 7 is formed in a portion 61c of the pressure reducing valve case 61.

[0014] Furthermore, in order to achieve the above object based on the air respirator according to claim 1 or 2, the air respirator according to the invention of claim 3 has a connecting port 2, for example, as shown in FIG. an air pressure switch 9 that detects the supply pressure of pressurized air to the air pressure and switches the opening and closing at a predetermined alarm pressure; and a residual pressure alarm connected to the air pressure switch 9 to be activated when the supply pressure falls below the alarm pressure. 10.

Furthermore, in order to achieve the above object, the air respirator according to the invention of claim 4 has a connection port 2 connected to a pressurized air source, and a connection port 2 connected to a pressurized air source, and a an air pressure switch 9 that detects the supply pressure of pressurized air to the connection port 2 and switches on/off at a predetermined alarm pressure.
and a residual pressure alarm 10 connected to the air pressure switch 9 so as to be activated when the supply pressure falls below the alarm pressure.

[0016]

[Operation] In the air breathing apparatus according to any one of claims 1, 2, or 3, the pressurized air supplied to the connection port 2 is controlled by the pressure reducing valve 6 to a predetermined pressure slightly higher than the pressure outside the case 1. Since the pressure is reduced to a pressure of
Excessive air is prevented from being supplied to the outlet 4.

Further, in the air respirator according to the invention of claim 2 or the invention of claim 3 which is based on the invention of claim 2, the part 61c of the pressure reducing valve case 61 is thrust into the pressure regulating valve case 71, and Since the valve seat 72 of the pressure regulating valve 7 is formed in a portion 61c thereof, the number of parts can be reduced and the configuration of the air breathing apparatus can be simplified.

Furthermore, in the air respirator according to the invention of claim 3 or the invention of claim 4, when the supply pressure of pressurized air becomes less than a predetermined alarm pressure, the air pressure switch 9 is closed, for example, and the residual pressure alarm is activated. 10 will be activated and a warning will be given to the user from the air respirator. Further, when the supply pressure of pressurized air exceeds a predetermined alarm pressure, the air pressure switch 9 is opened, for example, and the operation of the residual pressure alarm 10 is stopped. Therefore, not only when the supply pressure of pressurized air is below the alarm pressure when starting the field of use, but also when the supply pressure drops below the alarm pressure during use, air respirators that are close to the user's face can be A warning will be given.

In the present invention, the alarm issued by the residual pressure alarm 10 may be one that appeals to the most suitable sense among the human senses depending on the environment in which it is used, such as a light emitting device that appeals to the human eye. , a warning due to discoloration, etc., an audible warning such as a warning sound or a human voice, etc. may be generated. Of course, it is possible to configure the system to emit alarms that appeal to two or more senses simultaneously or sequentially.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An air respirator according to an embodiment of the present invention will be described below with reference to FIG.

This air respirator has a connection port 2 at one end (the right end in the figure) for connecting a pressurized air supply source, and an outlet at the other end for discharging air for the user to breathe. It comprises a case 1' having an outlet 4, in which a passage 5 is formed which communicates the connection port 2 with the discharge port 4. A pressure reducing valve 6 and a pressure regulating valve 7, which are incorporated into the case 1, are interposed in this passage 5. In addition, a pneumatic switch 9 is located on the front side of one end of the case 1 (top and bottom in the figure).
and a residual pressure alarm 10 are assembled.

The case 1 is composed of a pressure reducing valve case 61 and a pressure regulating valve case 71, and the pressure reducing valve case 61 is further fitted into a main case 61a and an end portion on the left side of the main case 61a in an airtight manner. a straight tubular other end 61c, and a gland nut 61 that fixes the other end 61c to the main case 61a.
It is composed of b. Further, a hole 62 is formed in the pressure reducing valve case 61, passing through it from one end to the other end.

The central portion of the hole 62 is formed to have a larger diameter than the other portions to form a driving chamber 62b, and a portion of the hole 62 on one end side of the driving chamber 62b is spaced a predetermined distance from the driving chamber 62b. By arranging the valve seat 63 of the pressure reducing valve 6 at the position shown in FIG.

Furthermore, a connection port 2 to which a small air cylinder (not shown) is screwed is provided at one end of the case 1, that is, the lower side of the main case 61a (on the back side of the paper in the figure). A primary passage 51 that communicates the main case 61a with the valve chamber 62a extends through the main case 61a and the valve seat 63.

A valve element 64, which has a smaller diameter than the valve chamber 62a and moves forward and backward from the drive chamber 62b side toward the valve seat 63 to open and close the primary passage 51, is inserted into the valve chamber 62a. A piston 65 formed of an integral member with this valve element 64 is slidably fitted therein. The drive chamber 62b is divided by the piston 65 into an external pressure chamber 66 located on the valve chamber 62a side of the piston 65 and a secondary pressure chamber 67 located on the opposite side.
It is communicated with the outside of the case 1 through a communication hole 69 formed in the . Further, a communication passage 6 extending between the valve element 64 and the piston 65 and extending from the periphery of the valve element 64 to the other end surface of the piston 65 is provided.
8 is formed, and the valve chamber 62a and the secondary pressure chamber 67 are communicated via this communication passage 68. Further, a pressure setting spring 70 is inserted into the external pressure chamber 66 as necessary. In this way, the pressure difference acting on both sides of the piston 65, that is, the pressure outside the case 1 (external pressure) acting on one end surface of the piston 65, and the secondary pressure acting on the pressure setting spring 70 and the other end surface of the piston 65. By driving the valve element 64 forward and backward toward the valve seat 63 based on the pressure difference with the internal pressure (secondary pressure) of the pressure chamber 67, the secondary pressure is increased to be equal to or slightly higher than the external pressure. The pressure of compressed air is reduced. Also, a portion 62c of the hole 62 on the other end side than the drive chamber 62b, a secondary pressure chamber 67, a communication passage 68, and a valve chamber 6
2a constitutes a secondary passage 52 of the pressure reducing valve 6 which also serves as a primary passage of the pressure regulating valve 7.

The other end 61c of the pressure reducing valve case 61 is
The hole 62 is formed into a straight tube shape surrounding a portion 62c on the other end side than the drive chamber 62b, and its outer circumferential surface is formed into a stepped circumferential surface that becomes smaller in diameter on the other end side. Then, the small diameter portion of the other end 61c is inserted into the pressure regulating valve case 71, and the cylindrical guide portion 74 which is screwed to this small diameter portion within the pressure regulating valve case 71 and the stepped surface of the other end 61c are connected to each other. A side wall 71a on one end side of the pressure regulating valve case 71 is sandwiched between them.

The other end 6 inserted into the pressure regulating valve case 71
A valve seat 72 of the pressure regulating valve 7 is formed on the tip end surface of 1c. The guide portion 74 is disposed coaxially with the other end portion 61c and the hole 62, and a spring receiving seat 77 is inserted into the guide portion 74 so as to be slidable toward the valve seat 72. Furthermore, a valve shaft 78 extending from the other end surface of the valve element 73 of the pressure regulating valve 7 to the other end side of the spring seat 77 and the guide part 74 is connected to the axis of the guide part 74 and the hole 62. along the valve seat 72 so as to be able to slide back and forth toward the valve seat 72. The valve element 73 is pressed against the valve seat 72 by a pressure setting spring 79 inserted between the other end of the guide section 74 and the spring seat 77, thereby closing the secondary passage 52. be.

Further, an air chamber 53 is formed inside the pressure regulating case 71 to accommodate the valve seat 72, valve element 73, guide portion 74, spring seat 77, and pressure setting spring 79. A mouthpiece 3 is connected to the rear side of the other end. This air chamber 53 is a discharge port 4 formed in the mouthpiece 3.
The outlet 4 is connected to the outside of the case 1 through the air chamber 53, the secondary passage 52, and the primary passage 51, and the connection port 2 is connected to the outlet 4 through the air chamber 53, the secondary passage 52, and the primary passage 51. A passageway 5 is formed that communicates the outlet 2 with the outlet 4.

Further, the entire front surface (lower surface in the top of the figure) of the air chamber 53 is hermetically covered by an operating member 75. This actuating member 75 is configured such that at least a portion thereof is displaced in a direction perpendicular to the axis of the hole 62 of the pressure reducing valve case 61 in accordance with the pressure difference between the inside and outside of the pressure regulating valve case 71 . That is, at least a portion of the operating portion 75 is configured to move forward when the internal pressure of the air chamber 53 increases, and to move backward when the internal pressure of the air chamber 53 decreases. Examples of such an operating member 75 include a piston, a bellows, or a diaphragm.
Here, the actuating member 75 is constituted by a diaphragm that has excellent followability to fluctuations in pressure difference between inside and outside, has a simple shape, and can be made at relatively low cost.

The operation of the actuating member 75 is controlled by the valve shaft 7 via a lever 76 that swings using the other end of the guide portion 74 as a fulcrum.
8 and valve element 73. That is, when the actuating member 75 (in this case, the central part of the actuating member 75) is pushed backward by a certain amount or more, the lever 76 swings counterclockwise in the figure, and the valve shaft 78 and the valve element 73 move toward each other. When the valve element 73 is moved away from the valve seat 72 by driving toward the end side, the secondary passage 52 is opened and the pressure regulating valve 7 is opened. When the pressure regulating valve 7 is opened, the air chamber 53 inside the pressure regulating valve case 71
The internal pressure of the valve increases and the actuating member 75 is pushed back forward, and the pressure of the pressure setting spring 79 drives the valve shaft 78 and valve element 73 toward one end, causing the valve element 73 to come into contact with the valve seat 72 and By closing the passage 52, the pressure regulating valve 7 is closed. At this time, the lever 76 is swung clockwise in the figure by the pressure of the pressure setting spring 79 and is returned to a predetermined position. In this way, the pressure regulating valve 7 regulates the internal pressure of the air chamber 53 to a predetermined pressure set by the pressure setting spring 79 based on the external pressure, for example, a pressure equal to or slightly higher than the external pressure. It is configured.

Note that the operating member 75 is connected to the pressure regulating valve case 7.
In this embodiment, a cover 71c for protecting the actuating member 75 is provided on the front side of the pressure regulating valve case 71. Also, this cover 71
A purge button 8 for forcibly pushing the actuating member 75 backward by a certain amount or more and forcibly opening the pressure regulating valve 7 is provided in the center of the purge button 8 so as to be movable forward and backward. Furthermore, a discharge valve 20 is provided at the rear side of the other end of the pressure regulating valve case 71 for discharging retained substances such as water retained within the air chamber 53.

A primary passage 51 is provided at one end of the case 1.
A pneumatic pressure switch 9 which is opened and closed in response to the internal pressure of the primary passage 51, and a residual pressure alarm 10 which operates and issues an alarm when the internal pressure of the primary passage 51 drops below a predetermined alarm pressure Pmin are provided.

The air pressure switch 9 is configured such that the internal pressure of the primary passage 51 is set to an alarm pressure Pmin higher than an external pressure, for example, a predetermined operating pressure Pe that is slightly higher than atmospheric pressure.
It suffices if it is configured so that it can be switched between opening and closing. Here, a cylinder chamber 91 communicating with the primary passage 51 is formed on the front side of the main case 61a, and a piston 92 is slidably inserted into the cylinder chamber 91 to connect the cylinder chamber 91 to the pressure receiving chamber 9.
1a and an operating pressure setting chamber 91b, the pressure receiving chamber 91a is communicated with the connection port 2 via the primary passage 51,
An operating pressure setting spring 93 is inserted into the operating pressure setting chamber 91b to bias the piston 92 toward the pressure receiving chamber 91a. By moving the piston 92 and the piston rod 94 connected thereto against the spring 93 in accordance with the internal pressure of the primary passage 51, when the air pressure in the primary passage 51 is lower than the operating pressure Pe, In this case, the switch body 95 is placed in an inoperative state in which it is not operated by the piston rod 94, and the switch body 95 is turned off (or on), for example.
is maintained, and when the air pressure in the primary passage 51 is equal to or higher than the operating pressure Pe, the switch body 95 is configured to be placed in an operating state operated by the piston rod 94. Further, when the internal pressure of the primary passage 51 is equal to or higher than the operating pressure Pe, the alarm pressure Pmi
If the internal pressure of the primary passage 51 exceeds the alarm pressure Pmin, the switch body 95 is turned on (or off), which is the opposite of the non-operating state. It is configured to switch off (or on).

The residual pressure alarm 10 is one that issues an alarm that appeals to the most suitable human senses in accordance with the environment in which the air breathing apparatus is used. Here, an audible alarm is used. I'm using one that has a speaker that emits the sound. That is, this residual pressure alarm 10 has a main case 6.
It is stored in a casing 18 fixed to the front side of 1a,
It is composed of a speaker body 11, a speaker plate 12, a resonance ring 13 that resonates with the vibrations of the speaker body 11 and causes the speaker plate 12 to vibrate greatly, and a printed circuit board 16. In order to prevent the atmosphere around the air breathing apparatus from mixing with the atmosphere inside the main case 61a,
A sealing member 14 made of an O-ring is interposed. Further, a cover 15 for protecting the speaker plate 12 is screwed onto the front part of the casing 18. This cover 15 is formed with a large number of holes, grooves (not shown) passing through its front end wall so that the vibration sound of the speaker plate 12 can be sufficiently dissipated to the outside.

The speaker body 11 has a printed circuit board 16
It is connected to the switch body 95 via. This printed circuit board 16 is configured to operate the speaker body 11 to generate sound when the pneumatic switch 9 is on (or off), and to stop the operation of the speaker body 11 when it is off (or on). Note that the power source of the electronic circuit provided across the pneumatic switch 9, the printed circuit board 16, and the speaker body 11 is, for example, mounted on the printed circuit board 16 so as to be replaceable.

In this air breathing apparatus, when no air cylinder is connected to the connection port 2, the internal pressure of the primary passage 51 is the same as the pressure around the air breathing apparatus (for example, atmospheric pressure), so the air pressure switch 9 is switched off. is turned off (or on) and the residual pressure alarm 10 does not operate. When an air cylinder is connected to the connection port 2 and pressurized air exceeding a predetermined alarm pressure Pmin is supplied to the primary passage 51, the air pressure switch 9 is momentarily turned on and then turned off again, reducing the residual pressure. The alarm 10 operates momentarily, issues an alarm, and then stops. The user can use this instantaneously activated residual pressure alarm 10.
By hearing the alarm, it can be confirmed that pressurized air exceeding the predetermined alarm pressure Pmin has been supplied to the primary passage 51. Furthermore, when an air cylinder is connected to the connection port 2 and the supply pressure of pressurized air to the primary passage 51 is higher than the predetermined operating pressure Pe and lower than the alarm pressure Pmin, the air pressure switch 9 is turned on. After that, the residual pressure alarm 10 continues to operate and continuously issues an alarm without being turned off. Therefore, by hearing this continuous alarm, the user may be aware that the outlet valve of the air cylinder is insufficiently opened, or that the supply pressure of the air cylinder may drop within a short period of time, causing an oxygen deficiency accident. In addition, the operator is encouraged to increase the opening amount of the outlet valve of the air cylinder or to replace the air cylinder. Further, although an air cylinder is connected to the connection port 2, the supply pressure of pressurized air to the primary passage 51 is at a predetermined operating pressure Pe.
If the pressure is below , the air pressure switch 9 cannot be switched from the non-operating state to the operating state, so the residual pressure alarm 10 will not operate at all. Therefore, by recognizing that the residual pressure alarm 10 is not instantaneously activated when the supply of pressurized air is started, the user can confirm that the outlet valve of the air cylinder is insufficiently opened, or that the outlet valve of the air cylinder is insufficiently opened. It is possible to know that the use of an air cylinder may cause danger within a short period of time, and the user is prompted to increase the opening amount of the outlet valve of the air cylinder or to replace the air cylinder.

Before the air cylinder is connected to the connection port 2,
The pressure regulating valve 7 is closed by the pressure of the pressure setting spring 79, and the pressure reducing valve 6 is held open by the pressure of the pressure setting spring 70. Further, when the supply pressure from the air cylinder connected to the connection port 2 to the primary passage 51 is lower than the predetermined operating pressure Pe, the internal pressure of the secondary pressure chamber 67 increases to above atmospheric pressure, but the pressure setting spring The pressure reducing valve 7 is kept open by the atmospheric pressure in the pressure chamber 70 and the external pressure chamber 66. When the supply pressure of pressurized air to the primary passage 51 is equal to or higher than the predetermined operating pressure Pe, the internal pressure of the secondary pressure chamber 67 is lowered by the pressure setting spring 70 and the external pressure chamber 6.
The valve element 64 of the pressure reducing valve 6 is moved to the valve seat 63 by overcoming the atmospheric pressure of the pressure reducing valve 6.
to close the pressure reducing valve 6. As a result, the secondary passage 52 is filled with air whose pressure has been reduced to approximately the operating pressure Pe, which is slightly higher than atmospheric pressure.

After that, the air chamber 53 is opened by operating the discharge valve 20.
When the purge button 8 is pressed after discharging the stagnant matter inside, the air in the secondary passage 52 flows into the air chamber 53, and the air stagnant in the air chamber 53 is discharged to the outside. , the internal pressure of the secondary passage 52 decreases. However, when the internal pressure of the secondary passage 52 decreases, the pressure reducing valve 6 opens and the secondary passage 52 opens.
The internal pressure of the air chamber 53 is restored, and the internal pressure of the air chamber 53 communicating with the air chamber 53 is also lower than the operating pressure Pe, but is increased to a higher pressure than the atmospheric pressure. The purge button 8 is kept pressed until a period of time has elapsed when all the air stagnant in the primary passage 51, secondary passage 52, and air chamber 53 is thought to have been discharged from the discharge port 4. Then, when you release the purge button 8, the air chamber 5
3 flows out from the outlet 4 to form an air chamber 53.
The internal pressure decreases to atmospheric pressure, and the valve element 73 is pressed against the valve seat 72 by the pressure setting spring 79, so that the pressure regulating valve 7 is closed. Further, by closing the pressure regulating valve 7, the pressure drop in the secondary passage 52 is stopped, and when the internal pressure in the secondary passage 52 is restored to about the operating pressure Pe, the pressure reducing valve 6 is also closed.

Furthermore, after this, when the user breathes with the mouthpiece 3 in his/her mouth, the internal pressure of the air chamber 53 becomes lower than atmospheric pressure, and the actuating member 75 is pushed backwards by atmospheric pressure, causing the pressure regulating valve 7 to open. The valve is opened. New air then flows into the air chamber 53 from the secondary passage 52 until the internal pressure of the air chamber 53 recovers to a predetermined pressure slightly higher than atmospheric pressure. Further, when the internal pressure of the secondary passage 52 is reduced by a certain level or more in accordance with this, the pressure reducing valve 6 is opened and the internal pressure of the secondary passage 52 is restored to a predetermined secondary pressure.

[0040] Thus, in this air breathing apparatus,
A pressure reducing valve 7 is provided on the primary side of the pressure regulating valve 7, which is opened when the user breathes, to reduce the pressure of the air supplied to the connection port 2 to an operating pressure PO slightly higher than atmospheric pressure. , excessive air is prevented from being supplied to the air chamber 53 on the downstream side of the pressure regulating valve 7 when the pressure regulating valve 7 is opened. As a result, there is no need to wastefully release air into the surrounding area.
It is possible to prevent the usage time of the air cylinder from being shortened due to wasteful air supply.

Furthermore, when the remaining amount of pressurized air in the air cylinder decreases below a certain level while using this air breathing apparatus, and the supply pressure to the primary passage 51 becomes below the alarm pressure Pmin, the air pressure switch 9 is switched. The residual pressure alarm 10 starts to operate. Since this residual pressure alarm 10 is located close to the face while using the air respirator, the user should especially
It is possible to easily and reliably recognize that the remaining amount of pressurized air has fallen below a predetermined amount without having to look for it. As a result, it becomes possible to prevent oxygen deficiency accidents from occurring due to overlooking the fact that the remaining amount of pressurized air is low.

Moreover, in this air breathing apparatus, the other end 61c of the pressure reducing valve case 61 is inserted into the pressure regulating valve case 71, and the pressure regulating valve 7 is inserted into the other end surface of the pressure reducing valve case 61.
Since the valve seat 72 is formed, the number of parts is reduced and the configuration can be simplified.

[0043] In the above embodiment, the pneumatic pressure switch 9 is configured to be held in the inoperative state when it is below the operating pressure Pe, but the pneumatic pressure switch 9 is Alternatively, a pressure switch may be provided which separately detects the internal pressure of the primary passage 52 and is switched on/off based on the operating pressure Pe, and the pressure switch and the air switch 9 may be connected in series. .

Furthermore, in the above embodiment, the residual pressure alarm 10
Although the residual pressure alarm device 10 is configured to issue an audible alarm, the residual pressure alarm 10 may be configured to issue a visual alarm instead of or in addition to this. Examples of visually appealing warnings include text display on a light emitting panel (LEP), continuous light emission by a light emitting diode (LED), flashing light emission, and switching of light emission colors.

Furthermore, in the above embodiments, the present invention is applied to a mouthpiece type air respirator used in the atmosphere, but the present invention also applies to a mouthpiece type air respirator used underwater, It can also be applied to mask-type air respirators used in the atmosphere or underwater.

[0046]

Effect of the invention As described above, claims 1, 2 or 3
According to the air respirator according to the invention, a pressure reducing valve is provided upstream of a pressure regulating valve that is opened and closed by the user's breathing, and the supplied pressurized air is equal to or higher than the surrounding pressure of the air respirator. Since the pressure is reduced to a slightly higher pressure, it is possible to prevent excess air from flowing out when the pressure regulating valve is opened, and there is no need to wastefully release air to the surroundings. This has the effect of preventing an increase in the burden on the air pressurizing device of the air supply source and a reduction in the usage time of the air cylinder.

Further, in the air respirator according to the invention of claim 2 or 3, the case is composed of a pressure reducing valve case of the pressure reducing valve and a pressure regulating valve case of the pressure regulating valve, and a part of the pressure reducing valve case is inserted into the pressure regulating valve case. By forming the valve seat of the pressure regulating valve in a portion thereof, the number of parts can be reduced and the configuration can be simplified.

Furthermore, according to the air breathing apparatus according to the invention of claim 3 or 4, when the supply pressure of the pressurized air supply source drops below a predetermined value, the residual pressure alarm built into the air breathing apparatus is activated. Therefore, if the supply pressure of pressurized air supplied from the pressurized air supply source drops below a predetermined value during use, a residual pressure alarm near the user will issue an alarm. It will be done. Therefore, the user is freed from the trouble of searching for and checking the residual pressure alarm, and can easily and reliably recognize the alarm even while the user is unaware of the air supply. . As a result, this greatly helps in preventing oxygen deficiency accidents that occur due to failure to notice that the supply pressure of pressurized air supplied from the pressurized air supply source has fallen below a predetermined value.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional plan view of an air respirator according to an embodiment of the present invention.

[Explanation of symbols]

1 Case 2 Connection port 4 Discharge port 5 Passage 6 Pressure reducing valve 7 Pressure regulating valve 9 Air pressure switch 10 Residual pressure alarm 61 Pressure reducing valve case 61c Part of pressure reducing valve case 61 (other end) 71
Pressure regulating valve case 72 valve seat

Claims (4)

[Claims] Claim 1: A case (1) having a connection port (2) for connecting a pressurized air supply source at one end and a discharge port (4) for discharging air for breathing by a user at the other end;
1), and the connection port (2) formed in the case (1).
) is incorporated into the case (1), and the pressurized air supplied to the connection port (2) has a pressure slightly lower than the pressure outside the case (1). a pressure reducing valve (6) that reduces the pressure to a high predetermined pressure;
and a pressure regulating valve (7) that opens and closes the passage 5 between the discharge port (4) and the pressure regulating valve (7) that opens when the user sucks air in the passage (5) from the discharge port (4). An air breathing apparatus characterized by: [Claim 2] The case (1) is a pressure reducing valve case (61) of the pressure reducing valve (6) and a pressure regulating valve case (71) of the pressure regulating valve (7).
A part (61c) of the pressure reducing valve case (61)
) into the pressure regulating valve case (71), and the pressure regulating valve (7
2. An air breathing apparatus according to claim 1, wherein the valve seat (72) is formed with a valve seat (72) of a valve seat (72). 3. An air pressure switch (9) that detects the supply pressure of pressurized air to the connection port (2) and switches on/off at a predetermined alarm pressure, and a pneumatic switch (9) that is activated when the supply pressure falls below the alarm pressure. The residual pressure alarm (
10) Claim 1 or 2 characterized by comprising:
Air respirators as described in. [Claim 4] A connection port (2) connected to a pressurized air source.
and an outlet (4) for releasing air for the user to breathe.
A passage (5) that communicates the discharge port (4) with the connection port (2), and a pneumatic switch (9) that detects the supply pressure of pressurized air to the connection port (2) and switches on/off at a predetermined alarm pressure. and a residual pressure alarm (10) connected to an air pressure switch (9) so as to be activated when the supply pressure falls below an alarm pressure.