Patent Description:
Firefighters perform rescue operations in dangerous places such as a site of a fire. Therefore, firefighters wear breathing apparatuses when performing rescue operations.

As to such a breathing apparatus, <CIT> (PTL <NUM>) discloses a positive pressure breathing apparatus. <CIT> (PTL2) discloses another example of breathing apparatus.

A conventional breathing apparatus has, in some cases, made it difficult for a firefighter who is a wearer to move.

According to an aspect, there is provided a facepiece that covers a face of a wearer, the facepiece including: a front surface plate that is a transparent plate-like member having a size that can cover the face of the wearer; and a rotation mechanism passing through the front surface plate on either a right or left side of the wearer and being rotatable with respect to the front surface plate.

Since the facepiece configured as described above includes the rotation mechanism passing through the front surface plate on either the right or left side of the wearer and being rotatable with respect to the front surface plate, forward visibility of the wearer is not obstructed. As a result, the movement of the wearer is not hindered.

The rotation mechanism includes: a first member fixed to the facepiece and having an opening; and a second member fitted into the opening to be rotatable with respect to the first member and having a path, the path passing through the front surface plate and allowing gas to flow therethrough. In this case, the path allowing the gas to flow therethrough is formed by the second member, and thus, the gas can flow stably.

Preferably, the facepiece further includes: a rotatable third member; and a stop member fixed to the first member and being capable of stopping rotation of the third member by engaging with the third member. In this case, the rotation of the second member and the third member can be stopped at a prescribed position by the stop member, and thus, the movement of the wearer is not hindered.

A breathing apparatus includes: any facepiece described above; and a cylindrical member connected to the rotation mechanism of the facepiece, the cylindrical member including: a flexible tube; and a metallic and flexible protective member that covers the tube.

Each embodiment according to the present invention will be described hereinafter with reference to the drawings. In the following description, the same parts and components are denoted by the same reference characters. Their names and functions are also the same. Therefore, detailed description about them will not be repeated.

<FIG> is a perspective view of a facepiece <NUM> according to an embodiment.

Facepiece <NUM> is used in a state of being mounted on a head of a human body. Facepiece <NUM> includes a facepiece main body <NUM> that covers a face of a wearer in the mounted state, and a head strap <NUM> for fixing facepiece main body <NUM> to a head of the wearer in the mounted state.

Facepiece main body <NUM> includes a front surface plate <NUM> that is a colorless and transparent plate-like member having a size that can cover the face of the human body, and a support <NUM> that supports front surface plate <NUM> in front of the face of the wearer at an adequate interval from the face of the wearer in the mounted state. Front surface plate <NUM> is also referred to as "eyepiece".

Hereinafter, one surface of front surface plate <NUM> in the thickness direction that is directed toward the face of the wearer in the mounted state will be referred to as "inner surface", and a surface opposite to the inner surface will be referred to as "outer surface".

Front surface plate <NUM> includes an upper portion <NUM> arranged to face a substantially upper half of the face of the wearer in the mounted state, and a lower portion <NUM> connecting to a lower end of upper portion <NUM> and arranged to face a substantially lower half of the face of the wearer in the mounted state. Upper portion <NUM> and lower portion <NUM> are formed to connect to each other in a bent manner. Specifically, upper portion <NUM> and lower portion <NUM> are formed such that lower portion <NUM> is bent toward the inner surface side with respect to upper portion <NUM>.

Each of upper portion <NUM> and lower portion <NUM> is formed to have a smoothly curved shape so as to be convex in a direction away from the face of the wearer between right and left ends in the mounted state. In addition, a through hole passing through lower portion <NUM> in the thickness direction is formed in a central portion of lower portion <NUM> between the right and left ends.

A nosecup holding portion to which one end of a nosecup <NUM> is fixed is provided on the inner surface side in the central portion of lower portion <NUM>.

Nosecup <NUM> is an annular seal member made of elastic soft rubber. Nosecup <NUM> is formed such that one end thereof is fixed to the nosecup holding portion, and the other end thereof is elastically in surface contact with a portion from an upper portion of the nose to both cheeks and the chin of the wearer, to thereby cover the mouth and the nose of the wearer in the mounted state. As described above, in the mounted state, an airtight breathing chamber is formed by nosecup <NUM> and the face of the wearer, and an intake gas is supplied to the breathing chamber.

A rotation mechanism <NUM> is attached to facepiece <NUM>. Rotation mechanism <NUM> is located midway between gas supply and pressure detection lines <NUM> and <NUM> and front surface plate <NUM>. One end of rotation mechanism <NUM> is connected to gas supply line <NUM> and pressure detection line <NUM>. The other end of rotation mechanism <NUM> is connected to front surface plate <NUM>. Facepiece <NUM> covers the face of the wearer. Facepiece <NUM> includes front surface plate <NUM> that is a transparent plate-like member having a size that can cover the face of the wearer, and rotation mechanism <NUM> passing through front surface plate <NUM> on either the right or left side of the wearer and being rotatable with respect to front surface plate <NUM>.

<FIG> and <FIG> are perspective views of a wearer <NUM> wearing facepiece <NUM> and a back carrier <NUM> according to the embodiment. Wearer <NUM> is wearing a protective clothing <NUM>. The head of wearer <NUM> is protected by a helmet <NUM>, facepiece <NUM> and a neck guard (Shikoro) <NUM>. Wearer <NUM> is carrying back carrier <NUM> on his back. A gas cylinder <NUM> is mounted on back carrier <NUM>. A pressure demand valve is not provided on a body front surface <NUM> of protective clothing <NUM> or facepiece <NUM>.

Back carrier <NUM> extends from an upper portion <NUM> to a lower portion <NUM>. Gas cylinder <NUM> having a shape extending from upper portion <NUM> to lower portion <NUM> is fixed to back carrier <NUM> by a band <NUM>. A tip of gas cylinder <NUM> is inserted between two rod-like portions <NUM> and <NUM> of back carrier <NUM>. Air that is an oxygen-containing gas for breathing is, for example, compression-filled into gas cylinder <NUM> as an intake gas at a pressure higher than the atmospheric pressure.

Lower portion <NUM> of back carrier <NUM> is provided with a bypass valve switch <NUM> and a positive pressure locking switch <NUM>. Bypass valve switch <NUM> is for guiding a high-pressure gas discharged from gas cylinder <NUM> to facepiece <NUM> without going through a pressure demand valve <NUM> and a regulator <NUM>.

Positive pressure locking switch <NUM> is for stopping a positive pressure supplied from gas supply line <NUM> to facepiece <NUM>. In a state where facepiece <NUM> is removed from wearer <NUM>, supply of the gas from gas supply line <NUM> to facepiece <NUM> continues, and thus, the supplied gas is released to the atmosphere without being used. In order to prevent this, positive pressure locking switch <NUM> is operated to interrupt the supply of the gas from gas supply line <NUM>, and thus, wasteful consumption of the gas can be suppressed.

Lower portion <NUM> of back carrier <NUM> is provided with a guard bar <NUM>. Guard bar <NUM> protects lower portion <NUM> of back carrier <NUM> and allows back carrier <NUM> to stand on the ground on its own.

<FIG> is a perspective view of rotation mechanism <NUM> and front surface plate <NUM> to which rotation mechanism <NUM> is attached according to the embodiment. As shown in <FIG>, rotation mechanism <NUM> includes a first main body <NUM>. First main body <NUM> includes a circular portion and a rectangular portion. An upper main body cover <NUM> and a lower main body cover <NUM> engage with the rectangular portion of first main body <NUM>.

A main body lock <NUM> engages with the circular portion of first main body <NUM>. Main body lock <NUM> is provided with notches 102a, 102b and 102c. Main body lock <NUM> is rotatable with respect to front surface plate <NUM>, together with first main body <NUM>.

A base <NUM> is provided to be in contact with front surface plate <NUM>. A plate spring <NUM> engages with base <NUM>. An engagement portion 118b provided at a tip of plate spring <NUM> abuts against main body lock <NUM>. Base <NUM> has an opening 105a.

A connector <NUM> is provided between base <NUM> and main body lock <NUM>. Base <NUM> and connector <NUM> do not rotate with respect to front surface plate <NUM>. When main body lock <NUM> is rotated, plate spring <NUM> fits into any one of notches 102a, 102b and 102c. As a result, the rotation of main body lock <NUM> can be stopped.

<FIG> is a perspective view of rotation mechanism <NUM> according to the embodiment. As shown in <FIG>, a cylindrical member <NUM> is fitted into first main body <NUM>. A main body screw <NUM>, connector <NUM> and a connector screw <NUM> are present around cylindrical member <NUM>. Base <NUM> is attached to connector <NUM>.

<FIG> is a cross-sectional view taken along line VI-VI in <FIG>. As shown in <FIG>, a second main body <NUM> is fitted into first main body <NUM>. An internal space 101a is provided in first main body <NUM>.

Second main body <NUM> is provided with protruding portions 111c and 111d extending in parallel with each other. Each of protruding portions 111c and 111d has a cylindrical shape, and internal spaces 111a and 111b thereof are provided to extend longitudinally. Internal spaces 111a and 111b communicate with internal space 101a of first main body <NUM>.

<FIG> is a cross-sectional view taken along line VII-VII in <FIG>. As shown in <FIG>, first main body <NUM> is sandwiched between upper main body cover <NUM> and lower main body cover <NUM>. Internal spaces 111a and 111b each having a circular shape are open to internal space 101a of first main body <NUM>.

Cylindrical member <NUM> is held in first main body <NUM>. A projecting portion 108c of cylindrical member <NUM> is fitted into a cylindrical portion 101c of first main body <NUM>. Cylindrical member <NUM> has a hollow shape and is located near a rotation axis of first main body <NUM>.

Main body screw <NUM> is screwed onto an outer circumference of cylindrical portion 101c. A part of projecting portion 108c is sandwiched between main body screw <NUM> and cylindrical portion 101c, such that cylindrical member <NUM> is positioned in first main body <NUM>.

Main body lock <NUM> is provided on the outer circumferential side of cylindrical portion 101c. A collar <NUM> and connector <NUM> are arranged between cylindrical portion 101c and main body lock <NUM>. Base <NUM> is located on the lower side of a flange portion 109f. Connector screw <NUM> is screwed onto an end of connector <NUM>. Front surface plate <NUM> is sandwiched between connector screw <NUM> and base <NUM>.

Plate spring <NUM> includes an annular portion 118a sandwiched between connector <NUM> and base <NUM>, and engagement portion 118b connected to annular portion 118a and engaging with main body lock <NUM>. Plate spring <NUM> is made of an elastic material.

The airtightness between facepiece <NUM> and rotation mechanism <NUM> is implemented by the following structure.

Inner hoses 210a and 220a that form a part of metal corrugated tubes for pressure detection and for gas supply are connected to protruding portions 111c and 111d of second main body <NUM> shown in <FIG>. Inner hoses 210a and 220a are made of rubber and the airtightness between protruding portions 111c and 111d and inner hoses 210a and 220a is maintained by contraction of the rubber.

Second main body <NUM> is coupled to first main body <NUM> by screwing, with a packing 111p interposed therebetween. The airtightness between first main body <NUM> and second main body <NUM> is maintained by a squeeze of packing 111p.

As shown in <FIG>, a Y packing <NUM> is in contact with first main body <NUM> and collar <NUM>. Y packing <NUM> is low in friction with respect to an outer diameter direction of the packing and can rotate while maintaining the airtightness between first main body <NUM> and collar <NUM>. In addition, by attaching main body screw <NUM> to first main body <NUM> by screwing, a fall of cylindrical member <NUM> from first main body <NUM> is prevented.

A packing <NUM> is provided between collar <NUM> and connector <NUM>. In addition, by rotating main body lock <NUM>, collar <NUM> is pressed against connector <NUM> with packing <NUM> interposed therebetween, and thus, the airtightness is maintained.

<FIG> is an exploded perspective view of rotation mechanism <NUM> according to the embodiment. As shown in <FIG>, connector <NUM> is provided with a lug 109t extending circumferentially. Main body lock <NUM> is provided with a groove 102n extending circumferentially. Lug 109t is fitted into groove 102n. Groove 102n is provided with a stopper (not shown), and a circumferential end of lug 109t hits the stopper, such that main body lock <NUM> can rotate by a prescribed angle with respect to lug 109t. Rotation mechanism <NUM> includes base <NUM> as a first member fixed to facepiece <NUM> and having opening 105a, and cylindrical member <NUM> as a second member fitted into opening 105a to be rotatable with respect to base <NUM> and having a path, the path passing through front surface plate <NUM> and allowing the gas to flow therethrough. Rotation mechanism <NUM> further includes main body lock <NUM> as a rotatable third member, and plate spring <NUM> as a stop member fixed to base <NUM> and being capable of stopping the rotation of main body lock <NUM> by engaging with main body lock <NUM>.

<FIG> is a perspective view of rotation mechanism <NUM> and front surface plate <NUM> to which rotation mechanism <NUM> is attached according to the embodiment. As shown in <FIG>, connector screw <NUM> is provided on the inner side of front surface plate <NUM>. A lug <NUM> of a deflector <NUM> engages with connector screw <NUM>. Thus, deflector <NUM> is positioned in front surface plate <NUM>.

<FIG> is a perspective view of back carrier <NUM> according to the embodiment. As shown in <FIG>, back carrier <NUM> includes a main body <NUM>. Main body <NUM> includes a front plate 330a and a back plate 330b.

Main body <NUM> extends longitudinally from upper portion <NUM> to lower portion <NUM>. Upper portion <NUM> is provided with a pair of belt holes <NUM>. Upper portion <NUM> refers to an upper half in the longitudinal direction, and lower portion <NUM> refers to a lower half in the longitudinal direction. That is, main body <NUM> includes upper portion <NUM> located on the neck side of the wearer, and lower portion <NUM> located on the waist side of the wearer.

Main body <NUM> is provided with four stoppers <NUM> for positioning the cylinder. A lid <NUM> is provided between stoppers <NUM>, and when lid <NUM> is removed, a recessed portion through which the gas supply line and the pressure detection line pass is exposed.

Main body <NUM> is provided with a first joint <NUM>. First joint <NUM> is provided to be rotatable about a rotation axis 311a with respect to main body <NUM>. A hose <NUM> is connected to first joint <NUM>. Hose <NUM> is provided to be rotatable about a rotation axis 312a with respect to first joint <NUM>. A second joint <NUM> is connected to hose <NUM>. Second joint <NUM> is provided to be rotatable about a rotation axis 313a with respect to hose <NUM>. A connector <NUM> provided at a tip of second joint <NUM> can be screwed onto a screwing portion <NUM> of a valve <NUM>.

The pair of rod-like portions <NUM> and <NUM> extend in a direction away from front plate 330a. The pair of rod-like portions <NUM> and <NUM> are connected to guard bar <NUM> in main body <NUM>. Rod-like portions <NUM> and <NUM> and guard bar <NUM> are manufactured by bending one rod.

Main body <NUM> is provided with a projecting portion <NUM>. Projecting portion <NUM> is provided with a belt hole <NUM>. Projecting portion <NUM> is provided closer to upper portion <NUM> with respect to bypass valve switch <NUM> and positive pressure locking switch <NUM>.

<FIG> shows a state in which gas cylinder <NUM> is mounted on back carrier <NUM>. As shown in <FIG>, by rotating first joint <NUM>, a position of connector <NUM> in the longitudinal direction can be determined.

<FIG> shows a state in which gas cylinder <NUM> is mounted on back carrier <NUM>. As shown in <FIG>, by rotating hose <NUM>, a position of connector <NUM> in a height direction can be determined.

<FIG> shows a state in which gas cylinder <NUM> is mounted on back carrier <NUM>. As shown in <FIG>, by rotating second joint <NUM>, an angle of connector <NUM> can be determined.

<FIG> shows a state in which gas cylinder <NUM> is mounted on back carrier <NUM>. As shown in <FIG>, by screwing connector <NUM> onto valve <NUM>, valve <NUM> and connector <NUM> can be connected to each other.

<FIG> shows gas supply line <NUM> and pressure detection line <NUM>. <FIG> is a cross-sectional view of gas supply line <NUM> and pressure detection line <NUM>. As shown in <FIG> and <FIG>, gas supply line <NUM> and pressure detection line <NUM> include inner hoses 210a and 220a made of rubber, and outer cases 210b and 220b covering inner hoses 210a and 220a, respectively. Outer cases 210b and 220b are flexible casing tubes, and are made of metal and bendable. As shown in <FIG>, connectors <NUM> and <NUM> are provided at opposing ends of gas supply line <NUM> and pressure detection line <NUM>.

<FIG> is a perspective view of back carrier <NUM>. As shown in <FIG>, back plate 330b extends from upper portion <NUM> to lower portion <NUM> of back carrier <NUM>. Lower portion <NUM> of back plate 330b is provided with a drain plug cover <NUM>. A cover 302a covers positive pressure locking switch <NUM>.

<FIG> is a perspective view of back carrier <NUM>, with drain plug cover <NUM> removed. As shown in <FIG>, when drain plug cover <NUM> is removed from back plate 330b, a drain plug <NUM> can be seen.

<FIG> is a perspective view showing an internal structure of back carrier <NUM>, with back plate 330b removed. As shown in <FIG>, an adjuster <NUM> is housed in front plate 330a. Adjuster <NUM> includes regulator <NUM> and pressure demand valve <NUM>. Pressure demand valve <NUM> is provided with drain plug <NUM>. Water <NUM> accumulated in pressure demand valve <NUM> can be discharged from drain plug <NUM>. Regulator <NUM> and pressure demand valve <NUM> are provided in lower portion <NUM> of the main body.

<FIG> is a perspective view showing an internal structure of back carrier <NUM>, with drain plug <NUM> removed from a case <NUM>. As shown in <FIG>, case <NUM> is provided with an opening <NUM>. Drain plug <NUM> is provided to fit into circular opening <NUM>.

<FIG> is a perspective view showing an internal structure of back carrier <NUM>, with adjuster <NUM> removed from back plate 330b. As shown in <FIG>, back plate 330b is provided with a groove 330c extending from upper portion <NUM> to lower portion <NUM>. Gas supply line <NUM> and pressure detection line <NUM> are arranged in groove 330c. When water enters pressure detection line <NUM>, the water comes to a dead end at case <NUM>, and thus, the water is likely to accumulate in this portion. By providing drain plug <NUM>, water <NUM> can be easily discharged.

<FIG> is a cross-sectional view showing an internal structure of pressure demand valve <NUM>. As shown in <FIG>, pressure demand valve <NUM> includes an adjuster main body <NUM>. Adjuster main body <NUM> includes an inlet portion <NUM> and a gas supply port <NUM> that is an outlet.

A pressure demand valve main body <NUM> is fitted into adjuster main body <NUM>. Pressure demand valve main body <NUM> cannot move with respect to adjuster main body <NUM>. A shaft <NUM> is slidably fitted into a cylindrical portion of pressure demand valve main body <NUM>.

Case <NUM> is in contact with adjuster main body <NUM>. Case <NUM> is provided with a diaphragm <NUM>. A positive pressure spring <NUM> is provided on one side of diaphragm <NUM>, and a lever <NUM> is provided on the other side of diaphragm <NUM>.

Case <NUM> is provided with a pressure detection port <NUM>. Pressure detection line <NUM> is inserted into pressure detection port <NUM>. A positive pressure locking shaft <NUM> is arranged in case <NUM>. A second auxiliary lever <NUM> is connected to positive pressure locking shaft <NUM>. A first auxiliary lever <NUM> is attached to a cap <NUM>. Positive pressure locking shaft <NUM> is connected to positive pressure locking switch <NUM>.

Pressure demand valve <NUM> has the function of supplying air having a pressure slightly higher than the atmospheric pressure to facepiece <NUM> in accordance with breathing. Pressure demand valve <NUM> implements the above-described function by the following structure.

Air having a medium pressure (<NUM> MPa or less) flows from inlet portion <NUM> of adjuster main body <NUM> to pressure demand valve main body <NUM>. The medium-pressure air is enclosed between pressure demand valve main body <NUM> and adjuster main body <NUM> by a first O ring <NUM> and a second O ring <NUM>.

Shaft <NUM> runs within pressure demand valve main body <NUM> and a valve body <NUM> is coupled to shaft <NUM> by a nut <NUM>. Valve body <NUM> is a composite member of metal and rubber. A rubber portion of valve body <NUM> is pressed against a sheet surface of pressure demand valve main body <NUM> by a valve spring <NUM> fixed by a spring receiver <NUM>, and thus, the flow of the medium-pressure air is stopped. In addition, a U seal <NUM> is attached to shaft <NUM> to prevent the medium-pressure air from flowing to the case <NUM> side.

Case <NUM> and pressure demand valve main body <NUM> are coupled to each other and an O ring <NUM> is provided in the coupled portion to prevent a pressure in case <NUM> from flowing to the atmosphere.

Case <NUM> connects to facepiece <NUM> through pressure detection port <NUM>, and pressure fluctuations in facepiece <NUM> that occur due to breathing are transmitted into case <NUM>. Diaphragm <NUM> is made of rubber and sandwiched between a cover <NUM> and case <NUM>, and thus, the air in case <NUM> does not leak to the cover <NUM> side.

Since case <NUM> is connected to facepiece <NUM> through pressure detection line <NUM>, the pressure in case <NUM> fluctuates due to breathing of wearer <NUM>. When the pressure in case <NUM> fluctuates, a shape of diaphragm <NUM> is deformed in response to the pressure fluctuation.

Lever <NUM> is connected to diaphragm <NUM>, and when diaphragm <NUM> is deformed, lever <NUM> rotates about a rotation shaft <NUM>. Rotation shaft <NUM> is fixed by cap <NUM>, and cap <NUM> is coupled to pressure demand valve main body <NUM>.

Adjuster main body <NUM> forms a case (main body) of regulator <NUM>. As a result, pressure demand valve <NUM> and regulator <NUM> are formed integrally with adjuster <NUM>. In other words, back carrier <NUM> includes adjuster <NUM> including regulator <NUM> and pressure demand valve <NUM> attached to main body <NUM> of back carrier <NUM> and integrated with each other.

Regulator <NUM> decompresses high-pressure air having a pressure P1 into medium-pressure air having a pressure P2. A high pressure valve sheet <NUM> is embedded in adjuster main body <NUM>. A shaft <NUM> of a piston <NUM> is in contact with high pressure valve sheet <NUM>. Piston <NUM> is housed in a decompression chamber <NUM>. A spring <NUM> presses piston <NUM>. When pressure P2 on the pressure demand valve <NUM> side becomes smaller, the force of pressure P2 pressing piston <NUM> becomes weaker and piston <NUM> moves from the position shown in <FIG> in a direction approaching shaft <NUM>. As a result, shaft <NUM> moves away from high pressure valve sheet <NUM> and the air flows through a passage <NUM> provided in shaft <NUM>. When pressure P2 at inlet portion <NUM> becomes higher due to the air, the force of pressure P2 pressing piston <NUM> becomes stronger and shaft <NUM> is pressed against high pressure valve sheet <NUM>.

An O ring <NUM> is provided between shaft <NUM> and adjuster main body <NUM>. An O ring <NUM> is provided between a head portion of piston <NUM> and adjuster main body <NUM>. The airtightness is maintained by these O rings <NUM> and <NUM>.

<FIG> is a cross-sectional view showing a state in which the medium-pressure air is flowing to gas supply port <NUM> in pressure demand valve <NUM> in accordance with an amount of breathing. As shown in <FIG>, when diaphragm <NUM> fluctuates due to breathing, lever <NUM> rotates. An end 405c of lever <NUM> presses an end 417c of shaft <NUM>. Valve body <NUM> moves in conjunction with shaft <NUM> and a gap is generated between pressure demand valve main body <NUM> and valve body <NUM>. As a result, the medium-pressure air flows to gas supply port <NUM> in accordance with the amount of breathing.

Gas supply port <NUM> connects to facepiece <NUM> through gas supply line <NUM>. The pressure in facepiece <NUM> fluctuates due to the air supplied to facepiece <NUM>, and the pressure fluctuation is detected at pressure detection port <NUM> through pressure detection line <NUM>, and diaphragm <NUM> moves due to the pressure fluctuation.

Positive pressure spring <NUM> fixed by cover <NUM> applies a load corresponding to an amount of compression to diaphragm <NUM>. Cover <NUM> is provided with a hole through which the atmospheric air is transmitted, and thus, positive pressure spring <NUM> and the neighborhood thereof have the atmospheric pressure. Due to the load applied by positive pressure spring <NUM>, the pressure in case <NUM> becomes higher than the atmospheric pressure.

<FIG> is a cross-sectional view taken along line XXIV-XXIV in <FIG>. When a breathing apparatus is not used, positive pressure locking shaft <NUM> is rotated. When positive pressure locking shaft <NUM> is rotated in a direction indicated by an arrow RS, second auxiliary lever <NUM> rotates in conjunction with positive pressure locking shaft <NUM> and a shaft <NUM>. Due to the rotation of second auxiliary lever <NUM>, second auxiliary lever <NUM> pushes up first auxiliary lever <NUM> and first auxiliary lever <NUM> runs onto a protrusion 426a provided on cap <NUM>, such that a position of first auxiliary lever <NUM> is fixed. Since the position of first auxiliary lever <NUM> is fixed, lever <NUM> does not allow first auxiliary lever <NUM> to climb over protrusion 426a of cap <NUM> and return to the original position, using only the force of positive pressure spring <NUM> transmitted through diaphragm <NUM>, and thus, lever <NUM> is fixed. Since lever <NUM> is fixed, valve body <NUM> does not open and the air does not flow into facepiece <NUM> through gas supply port <NUM>.

When the pressure in case <NUM> is reduced by air intake in this state, the force transmitted through diaphragm <NUM> increases and first auxiliary lever <NUM> climbs over protrusion 426a of cap <NUM> that fixes first auxiliary lever <NUM>, and thus, the fixation is released.

<FIG> shows wearer <NUM>, with neck guard (Shikoro) <NUM> lifted up. Since neck guard (Shikoro) <NUM> is lifted down in <FIG> and <FIG>, rotation mechanism <NUM> cannot be seen. However, since neck guard (Shikoro) <NUM> is lifted up in <FIG>, rotation mechanism <NUM>, gas supply line <NUM> and pressure detection line <NUM> are exposed. Gas supply line <NUM> and pressure detection line <NUM> are preferably arranged on the left side of wearer <NUM>. This is because wearer <NUM> carries a fire hose on his right shoulder. If gas supply line <NUM> and pressure detection line <NUM> are provided on the right side, gas supply line <NUM> and pressure detection line <NUM> interfere with the fire hose.

A structure for rotating and locking rotation mechanism <NUM> with respect to facepiece <NUM> is implemented by the following. First, annular portion 118a of plate spring <NUM> is attached to base <NUM>.

Base <NUM> is fitted to connector <NUM>. When main body lock <NUM> is rotated, any one of notches 102a, 102b and 102c of main body lock <NUM> engages with engagement portion 118b of plate spring <NUM>. As a result, main body lock <NUM> is no longer rotated.

In order to rotate main body lock <NUM>, engagement portion 118b is pressed down toward the base <NUM> side. This releases the engagement between engagement portion 118b and any one of notches 102a, 102b and 102c. As a result, main body lock <NUM> can be rotated.

A breathing apparatus <NUM> has the following features.

Adjuster <NUM>, which is a component of breathing apparatus <NUM>, is arranged in back carrier <NUM>. Thus, as compared with the case in which adjuster <NUM> is arranged on body front surface <NUM> of wearer <NUM>, adjuster <NUM> is not disconnected from the position where adjuster <NUM> is arranged, while wearer <NUM> is performing operations.

In back carrier <NUM>, an exposed portion of arranged adjuster <NUM> is covered with front plate 330a, which is a separate component. In addition, guard bar <NUM>, which is a self-standing fitting that is not in direct contact with adjuster <NUM>, is provided.

Adjuster <NUM> has such a structure that the regulating portion (regulator <NUM>) that regulates the high-pressure air and the supply portion (pressure demand valve <NUM>) that supplies an appropriate amount of the regulated air to the wearer in accordance with an amount of breathing are integrated with each other.

Gas supply line <NUM> and pressure detection line <NUM>, which are hoses for breathing (breathing hoses) that couple facepiece <NUM> to adjuster <NUM>, connect to facepiece <NUM> from the back of the wearer without going through body front surface <NUM>.

A part of gas supply line <NUM> and pressure detection line <NUM> are housed in back carrier <NUM>. In conjunction with the movement of the neck of wearer <NUM>, gas supply line <NUM> and pressure detection line <NUM> extend and contract by a distance of the movement of the neck.

The connection fitting (rotation mechanism <NUM>) that connects facepiece <NUM> to gas supply line <NUM> and pressure detection line <NUM> is rotatable with respect to facepiece <NUM>, while maintaining a protected state from the outside air in facepiece <NUM> when breathing apparatus <NUM> is worn.

The hose that connects breathing apparatus <NUM> to the high-pressure air container (gas cylinder <NUM>) has such a structure that the fitting for connection of the hose (hereinafter, high pressure hose connection fitting) has the multiple rotation axes and eccentricity during rotation allows connection to gas cylinders having different sizes.

At a site of a fire, quick and safe operations are required because of operations in a dangerous area. However, smoke produced by the fire impairs visibility. If visibility on the foot side becomes poor, quick and safe operations become difficult because there is a possibility of falling down in a site having a level difference. If adjuster <NUM>, gas supply line <NUM> and pressure detection line <NUM> are provided on the body front surface in this situation, downward visibility becomes poor due to the components of breathing apparatus <NUM>. In the present breathing apparatus, adjuster <NUM> is not provided on the body front surface, and gas supply line <NUM> and pressure detection line <NUM> are connected to facepiece <NUM> from the back of the body. Therefore, there are no components that obstruct downward visibility, and thus, visibility does not become poor.

When breathing apparatus <NUM> is used for operations in a narrow space, movements such as lying on wearer's stomach, squatting, and holding a ladder may be required in some cases. If adjuster <NUM>, gas supply line <NUM> and pressure detection line <NUM> are provided on body front surface <NUM>, ease of operation is inhibited due to interference with the components.

In breathing apparatus <NUM> according to the embodiment, adjuster <NUM>, gas supply line <NUM> and pressure detection line <NUM> are not provided on the body front surface. Therefore, wearer <NUM> can bring his body into close contact with the ground or a ladder, and thus, ease of operation is enhanced.

Breathing apparatus <NUM> according to the embodiment is provided with the component that covers the exposed portion of adjuster <NUM>, and guard bar <NUM> which is a self-standing fitting that is not in direct contact with adjuster <NUM>. Therefore, breathing apparatus <NUM> according to the embodiment has a structure for protecting adjuster <NUM> against impacts caused by collision and falling.

By integrally forming adjuster <NUM>, the hose (hereinafter, medium pressure hose) that connects regulator <NUM> to pressure demand valve <NUM> becomes unnecessary. Since the medium pressure hose is made of rubber, the medium pressure hose deteriorates over time. However, since the hose becomes unnecessary, the maintainability is enhanced. In addition, since the medium pressure hose becomes unnecessary, adjuster <NUM> is reduced in size.

When wearer <NUM> looks right and left and up and down, or when wearer <NUM> takes various postures, the neck of wearer <NUM> moves. When the neck moves beyond the elasticity of the hose, the hose is pulled by the movement of the neck. When the hose is designed to flex with the movement of the neck taken into consideration, wearer <NUM> may be caught by the hose during operation if the hose is excessively exposed on the body front surface.

In breathing apparatus <NUM> according to the first embodiment, gas supply line <NUM> and pressure detection line <NUM> extend and contract in accordance with the movement of the neck, and thus, stress on the neck portion is relieved. In addition, gas supply line <NUM> and pressure detection line <NUM> are housed in back carrier <NUM>, and thus, excessive exposure of the hose is suppressed and ease of operation is enhanced.

Since rotation mechanism <NUM> rotates, the up and down and right and left movement of the neck is followed when breathing apparatus <NUM> is worn, and thus, stress on the neck portion is relieved.

In addition, when water enters gas supply line <NUM>, pressure detection line <NUM> and adjuster <NUM> through the facepiece as a result of assisted water spraying or the like, in a state where breathing apparatus <NUM> is worn and facepiece <NUM> is taken off (standby state), the water causes a failure of breathing apparatus <NUM> due to corrosion of the components or freezing under low temperature. Since rotation mechanism <NUM> rotates, facepiece <NUM> can be rotated in the standby state so as to be oriented in a direction that prevents entry of the water of assisted water spraying.

Gas cylinder <NUM> varies in internal volume depending on an amount of carried air, and thus, varies in size of the container itself. In contrast, the hose connecting to gas cylinder <NUM> generally has a multilayer structure in order to withstand the high-pressure air, and thus, the hose itself is inferior in elasticity. Therefore, when the hose is connected to gas cylinders <NUM> having different sizes, it is necessary to provide a degree of freedom for the high pressure hose connection fitting, or to adjust a position where each gas cylinder <NUM> is fixed to the back carrier. In the case of providing the degree of freedom for the high pressure hose connection fitting, sliding of the high pressure hose connection fitting for position adjustment applies the frictional force due to a mass of the component and a configuration of a component connected to the high pressure hose connection fitting. Since connection to gas cylinder <NUM> is performed whenever breathing apparatus <NUM> is used, the repeated action leads to stress of wearer <NUM> and device wear.

A high pressure hose connection fitting <NUM>, which is a guide path that guides the gas of gas cylinder <NUM> from outside main body <NUM> to inside main body <NUM>, is provided between gas cylinder <NUM> and regulator <NUM>. High pressure hose connection fitting <NUM> includes first joint <NUM>, hose <NUM> and second joint <NUM>. High pressure hose connection fitting <NUM> is rotatable along a plurality of axes. By providing the multiple rotation axes to high pressure hose connection fitting <NUM> for connection, the connectivity to gas cylinder <NUM> is enhanced. In the present embodiment, high pressure hose connection fitting <NUM> has three rotation axes 311a, 312a and 313a. However, high pressure hose connection fitting <NUM> may have more or fewer rotation axes.

It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims.

Claim 1:
A facepiece (<NUM>) that covers a face of a wearer, the facepiece comprising:
a front surface plate (<NUM>) that is a transparent plate-like member having a size that can cover the face of the wearer; and
a rotation mechanism (<NUM>) passing through the front surface plate on either a right or left side of the wearer and being rotatable with respect to the front surface plate, wherein
the rotation mechanism includes:
a first member (<NUM>) fixed to the facepiece and having an opening; and
a second member (<NUM>) fitted into the opening to be rotatable with respect to the first member and having a path, the path passing through the front surface plate and allowing gas to flow therethrough,
and wherein one end of the rotation mechanism (<NUM>) is connected to a gas supply line (<NUM>) and pressure detection line (<NUM>), and
the other end of the rotation mechanism (<NUM>) is connected to the front surface plate (<NUM>).