JP2004275638A - Gas mask and remaining capability indicating device for gas absorbing agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a user of a gas mask to evaluate a remaining capability of a gas absorbing agent without stopping his work. <P>SOLUTION: A display equipment 1 having a transparent observation window 1b is placed on an absorbing canister 221 of the gas mask to check the color of a detecting agent 1c from the outside. The display equipment 1 comprises a cylindrical body 1a that is shorter than the depth of a chassis 2 of the absorbing canister, the solid observation window 1b that is inserted into the cylindrical body 1a and hermetically connected to the inside of the cylindrical body 1a, and the detection agent 1c filled in the cylindrical body 1a, which is inside the chassis 2 behind the observation window 1b. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention enables a gas mask and a user to visually determine the detoxification ability remaining in a toxic gas absorbent (hereinafter, referred to as “gas absorbent”) filled in an absorbent can. Related to a display device.
[0002]
[Prior art]
Gas masks are used to protect users in working environments where toxic gases, such as organic solvent vapors, ammonia, chlorine, sulfur dioxide or carbon monoxide, drift. The gas mask generally includes a replaceable absorbent can filled with a gas absorbent containing activated carbon as a main component. Here, the detoxification ability of the gas absorbent is lost when the gas absorbent adsorbs the specified amount of toxic gas, and when the absorbent can is continued to be used after the detoxification ability is lost, the toxic gas is absorbed. It passes through the can and the user will inhale it. In order to prevent such an accident, it is necessary to accurately evaluate the detoxification ability remaining in the gas absorbent (hereinafter referred to as “residual ability”).
[0003]
The following methods are known as methods for evaluating the residual capacity of the gas absorbent of the gas mask.
The first method is to suspend use of the gas mask, remove the absorbent can, attach a gas detector downstream of it, take in air in the working environment, and evaluate the remaining capacity from the measurement results of the gas detector. is there.
[0004]
The second method is to attach a gas sensor to the face of the gas mask (attached to the user's head and surround the breathing area) and monitor the toxic gas concentration of the gas passing through the absorber. Is what you do.
[0005]
In the third method, a transparent tubular body made of glass or the like is filled with a detecting agent that changes color upon contact with a toxic gas to constitute a detecting tube, and the tip of the tube is penetrated by penetrating the side surface of the absorbent can. It is inserted into a gas absorbent, and the residual capacity is visually evaluated from the state of the detector located outside the absorbent can. The detection tube configured as described above is generally called a diffusion type detection tube (Non-Patent Document 1 below).
[0006]
[Non-patent document 1]
Labor Science, Vol. 66, No. 12 (P568-574), 1990
[0007]
[Problems to be solved by the invention]
However, each of the above evaluation methods has the following problems.
That is, the first method has a problem that the operation must be interrupted in order to evaluate the remaining capacity of the gas absorbent. Another problem is that if the remaining capacity is lost during the work, the user cannot be poisoned until the next evaluation is performed.
[0008]
In the second method, it is necessary to install a special gas sensor and to construct a system for evaluating the remaining capacity of the gas absorbent from the detected toxic gas concentration, which causes a problem that the cost increases.
[0009]
In the third method, since the state of the detection agent is observed from a lateral direction with respect to the axis of the cylindrical body, a portion of the cylindrical body containing the detection agent necessarily projects outside the absorption can. Therefore, there is a problem that the work may be hindered due to this.
[0010]
In view of the circumstances described above, the present invention enables a user of a gas mask to evaluate the remaining capacity of a gas absorbent without interrupting work, and makes such a function structurally safe and inexpensive. It is intended to be realized by a simple configuration.
[0011]
[Means for Solving the Problems]
The present invention provides a gas mask and a gas absorbent residual capacity display device.
[0012]
The gas mask according to the present invention includes a face body, and a detoxification unit connected to the face body, which removes toxic components in the inhaled gas and passes the rest thereof. The detoxifying unit is provided inside the cylindrical body, a hollow cylindrical body inserted into the housing, and a casing having a predetermined depth in the gas flow direction, and a space inside the cylindrical body is provided. A substantially transparent observation window configured to block the flow of gas passing therethrough, and a toxic component to be removed, which is provided in an inner portion of the space inside the cylindrical body with respect to the inside and outside of the housing portion with respect to the observation window. And a detection agent that shows a different color before and after the contact.
[0013]
According to such a configuration, since the state of the detection agent can be visually confirmed through the transparent observation window provided inside the cylindrical body, the user of the gas mask can interrupt the work. The remaining capacity of the gas absorbent can be judged in a timely manner. In addition, since the detection agent can be located in the housing, the protrusion as in the conventional diffusion type detection tube can be eliminated.
[0014]
The gas absorbent residual capacity display device according to the present invention has a hollow cylindrical body, and a substantially transparent structure that is provided inside the cylindrical body and blocks a gas flow through a space in the cylindrical body. An observation window and a detection agent that is provided in a portion of the space inside the cylindrical body on one side of the observation window and that shows a different color before and after contact with a toxic gas to be removed by a gas absorbent. .
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1A to 1C show the appearance of various gas masks to which the present invention can be applied.
[0016]
FIG. 1A shows a gas mask 101 of a direct connection type, full-face type according to a first embodiment of the present invention.
The gas mask 101 is configured to include a resilient face body portion 11 made of rubber or the like and a detoxification portion 12 directly connected thereto. The face body portion 11 includes an eyepiece 111 surrounding the entire face of the user, and a nose cup 112 provided inside the eyepiece 111 and particularly surrounding the breathing area of the user. Attached to the head H.
[0017]
On the other hand, the detoxification unit 12 is for removing toxic components from the inhaled gas, and includes an absorption can 121 filled with a gas absorbent for absorbing the toxic components. The absorbent can 121 has a connection portion formed with a male screw, and is screwed into the absorbent can attachment portion 114 of the face body portion 11 to be connected to the face body portion 11. Further, the absorbing can 121 can be freely removed from the face body portion 11.
[0018]
FIG. 1B shows a direct-connecting small-sized half-faced gas mask 102 according to a second embodiment of the present invention.
The gas mask 102 is attached to a user's head (not shown) with a lace 211, and includes a face body 21 surrounding the respiratory region and a detoxifying unit 22 directly connected to the face body 21. . The face body portion 21 includes only a portion corresponding to a nose cup in a direct connection type full-surface type, and does not include a portion corresponding to an eyepiece.
[0019]
On the other hand, the detoxifying unit 22 is configured to include an absorbent can 221 filled with a gas absorbent and a ring-shaped holder 222 for fixing the absorbent can 221 to an absorbent can attachment portion of the face body 21. In the gas mask 102, the absorbent can 221 can be freely removed from the face body 21 by operating the holder 222.
[0020]
FIG. 1 (c) shows a gas mask 103 of an isolated full-surface type according to a third embodiment of the present invention.
The gas mask 103 includes a face body portion 31 including an eyepiece 311 and a nose cup 312 similar to those of a direct connection type full-surface type, and a detoxification portion 32 connected thereto via a connection pipe 351. Is done. The face body part 31 is attached to the head H of the user by a lace 313.
[0021]
On the other hand, the detoxification unit 32 is configured to include an absorption can 321 filled with a gas absorbent, and the absorption can 321 is fixed to a distal end portion of the connection pipe 351 by a fastening member 352. In the gas mask 103, the absorbent can 321 can be freely removed from the face body 31 by operating the fastener 352.
[0022]
FIG. 2 shows the appearance of the absorption can 121, 221 or 321 of the gas mask with the gas inlet side down.
In the following description, each part is specified by reference to the reference numerals used for the direct-connection small-sized half-faced gas mask 102 of FIG.
[0023]
The absorption can 221 of the gas mask 102 includes the housing 2 having a predetermined depth D in the gas flow direction, and the gas absorbent 4 filled therein. The housing portion 2 is provided with supports 3a and 3b made of a wire mesh or the like at both front and rear ends in the gas flow direction, whereby the gas absorbent 4 is held in the housing portion 2.
[0024]
In the gas mask 102, the gas absorbent residual capacity display device (hereinafter referred to as "display device") 1 according to the present invention is installed at a position indicated by reference numeral 1B in FIG.
[0025]
FIG. 3 shows an exploded configuration of the absorption can 221 of the gas mask 102. The configuration of the display device 1 will be described with reference to FIG.
The display device 1 includes a hollow cylindrical body 1a as a cylindrical body having a length L smaller than the depth D of the housing 2, and a solid and transparent window member having an outer diameter substantially equal to the inner diameter thereof. 1b, and a detection agent 1c that changes color upon contact with a specific gas. In the absorption can 221, a circular hole is provided at the center of the support 3 a provided on the gas inlet side, and the cylindrical body 1 a is formed from the outside of the housing 2 through the housing Inserted into 2. The cylindrical body 1a is hollow and the inside communicates with the outside before and after in the longitudinal direction. The window member 1b is shorter than the cylinder 1a and is inserted into the cylinder 1a. Then, both ends are hermetically joined in a state where the end surfaces on the outside with respect to the inside and outside of the casing 2 form the same plane as the end surface of the cylindrical body 1a on the same side. The window member 1b forms an observation window of the display device 1. In the cylindrical body 1a, the detecting agent 1c is filled in a space between an inner end surface of the window member 1b with respect to the inside and the outside of the housing portion 2 and an end surface of the cylindrical body 1a on the same side.
[0026]
The gas absorbent 4 contains activated carbon as a main component, and is filled in a portion of the space inside the housing portion 2 excluding the space occupied by the display device 1, and is supported by the supports 3a and 3b from both front and rear ends. The detecting agent 1c is appropriately selected according to the toxic gas to be removed by the gas absorbent 4, such as one capable of reacting with a plurality of gases such as hydrocarbons and one specialized for the working environment to be used. .
[0027]
Next, the function of the display device 1 of the gas mask 102 will be described with reference to FIG.
At the time of shipping the gas mask 102 or after the replacement of the absorption can 221, the gas absorbent 4 filled in the absorption can 221 is in a state A in which no toxic gas is adsorbed (FIG. 4A). When the user wears the gas mask 102 and starts working, gas in the working environment including toxic gas is drawn into the absorption can 221 bypassing the display device 1. The toxic gas sucked into the absorption can 221 is gradually adsorbed from the gas absorbent 4 on the inlet side (FIG. 4B). When the operation is further continued and the amount of toxic gas exceeding the specified amount is sucked, the entire gas absorbent 4 enters the state B in which the toxic gas is adsorbed, and the desorbing ability of the gas absorbent 4 is lost. In such a state, the sucked toxic gas passes through the absorption can 221 without being removed (FIG. 4D). This phenomenon is called breakthrough.
[0028]
The display device 1 according to the present invention displays the remaining capacity of the gas absorbent 4 in the color of the detecting agent 1c, and the user of the gas mask 102 can change the color of the gas absorbent 4 before the breakthrough. 221 can be replaced. That is, the length L of the cylindrical body 1a of the display device 1 is set in the range of 80 to 90% of the depth D corresponding to the replacement time of the absorbent can 221. Toxic gas is adsorbed from the inlet surface of the absorption can 221 to the depth of the inner end surface of the cylindrical body 1a with respect to the inside and outside of the housing portion 2, and the detoxification ability of that portion is lost, and the detecting agent 1c is converted into a toxic gas. When it comes into contact, the color of the detection agent 1c changes from pink before contact to yellow after contact (FIG. 4 (c)). This color change gradually proceeds from the outer periphery of the detection agent 1c near the inner surface of the cylindrical body 1a toward the inside. The user determines that the time when the entirety of the detection agent 1c has changed to yellow is the time to replace the absorbing can 221 and can replace the absorbing agent 221 before an accident of inhaling toxic gas due to breakthrough.
[0029]
FIG. 5 shows a configuration of a test device for evaluating the performance of the display device 1 as described above.
Ammonia gas was used as the toxic gas. Ammonia gas was supplied from a cylinder 501, which was diluted with clean air humidified with distilled water 502 to produce a suction gas. The clean air was produced by filtering air taken in from the atmosphere by the compressor 503 with a filter 504. An ammonia gas concentration measuring device (manufactured by MSA, trade name “CHILLGARD IR”) 505 was installed, and the ammonia gas concentration of the inhalation gas was kept at 1000 ppm, the humidity was kept at 50%, and the temperature was kept at 20 ° C. The absorption can 221 used in the experiment had an inner diameter of 70 mm and a depth of 18 mm, and was installed so that the suction gas flowed upward from below in view of the configuration of the test apparatus. An acrylic rod having an outer diameter of 10 mm and a length of 10 mm was used for the window member 1 b of the display device 1, and this was inserted into a cylindrical body 1 a having a depth of 14 mm, thereby producing the display device 1. . As the detecting agent 1c, an ammonia detection tube No. manufactured by Gastech Co., Ltd. was used. A powdery substance used as a detecting agent in 3 L was employed. Since the inhaled gas flows upward from below, a mirror 507 is provided in the measuring section 506 so that the state of the detecting agent 1c can be observed from the surroundings. The air that has passed through the absorbent can 221 is released into the atmosphere via the abatement agent 508. Note that reference numerals 509 and 510 denote pressure control valves, and reference numeral 511 denotes a pump.
[0030]
In the performance evaluation test using the device configured as described above, when the pump 511 is operated to cause the suction gas including the ammonia gas to flow into the absorption can 221, the detecting agent 1 c of the display device 1 is changed according to the increase of the flow amount. It was confirmed that the color gradually changed from the outer periphery. Further, ammonia gas was not detected downstream of the absorption can 221 until the entire color of the detection agent 1c changed color.
[0031]
The effects obtained by the display device 1 according to the present invention are summarized as follows.
First, the display device 1 is configured using the transparent window member 1b so that the state of the detection agent 1c can be visually confirmed from outside the absorption can 221. Thus, the user can determine the remaining capacity of the gas absorbent 4 without interrupting the operation, replace the absorbent can 221 before the breakthrough occurs, and avoid an accident of inhaling toxic gas.
[0032]
Second, in the cylindrical body 1a, the detecting agent 1c is filled into the inner end of the casing 2 with respect to the inside and outside, and is positioned so as to face the flow of the toxic gas. This makes it possible to surely change the color of the detection agent 1c as compared with a general diffusion type detection tube, and to reliably detect the risk of breakthrough.
[0033]
Third, since the detection agent 1c is located in the housing portion 2 and the end faces of the cylindrical body 1a and the window member 1b are included in the plane formed by the outer shell of the housing portion 2, the diffusion type detection tube is used. Certain projections can be eliminated, and structural safety can be improved.
[0034]
The absorbent can 221 including the display device 1 can be produced by an existing absorbent can production line, and can be attached to the face of a general gas mask. There is no particular change in the method of using the gas mask, and the gas mask can be used in the same manner as in the related art.
[0035]
In the above, the case where the cylindrical body 1a as a cylindrical body is inserted into the housing part 2 in the direction parallel to the gas flow direction in the housing part 2 for the direct connection type small half-faced gas mask 102 is described. As explained in the example. The present invention can be applied not only to the direct connection type small half-surface type but also to the direct connection type full surface type or the isolation type full surface type. The gas absorbent remaining capacity display device according to the present invention can also be used by inserting a tubular body into a housing in a direction perpendicular to a gas flow direction in the housing. That is, a hole is provided in the side surface of the housing, the display device is inserted into the hole, and the state of the detection agent is observed from the side of the housing. The installation position of the display device when applied to an isolated full-surface type is indicated by reference numeral 1C in FIG. According to the display device installed in this way, when the absorbent can is configured to include the housing portion having a depth larger than the inner diameter, the length of the display device can be reduced and the display device can be integrated into a compact configuration. it can.
[Brief description of the drawings]
FIG. 1 shows the configuration of various gas masks to which the present invention can be applied. FIG. 2 shows the appearance of an absorption can of the gas mask. FIG. 3 shows the configuration of the absorption can. FIG. 4 shows a display according to an embodiment of the present invention. Concept of remaining capacity display by device [Fig. 5] Configuration of performance test device for display device same as above [Description of reference numerals]
DESCRIPTION OF SYMBOLS 1 ... Gas absorbent remaining capacity display device, 1a ... Cylindrical body as a cylindrical body, 1b ... Window member to be an observation window, 1c ... Detector, 2 ... Case part, 3a, 3b ... Support, 4 ... Gas absorbent, 101: gas mask, 11: face body, 111: eyepiece, 112: nose cup, 113: lace, 114: absorption can attachment part, 12: detoxification part, 121: absorption can.

Claims (6)

A face body attached to the user's head and surrounding the respiratory area,
A detoxification unit connected to the surface unit, for removing toxic components in the inhaled gas and passing the rest thereof,
The detoxification unit has a housing having a predetermined depth in the gas flow direction,
A hollow cylindrical body inserted into the housing,
A substantially transparent observation window that is provided inside the cylindrical body and has a configuration for blocking a gas flow through a space in the cylindrical body,
A detection agent that is provided in an inner portion of the space within the cylindrical body with respect to the inside and outside of the housing portion with respect to the observation window and that has a different color before and after contact with the toxic component to be removed. mask. The gas mask according to claim 1, wherein the tubular body is inserted into the housing in a direction parallel to a gas flow direction in the housing. The gas mask according to claim 1, wherein the tubular body is inserted into the housing in a direction perpendicular to a gas flow direction in the housing. 4. The method according to claim 1, wherein the detection agent is filled in a space formed by the tubular body and the observation window, and provided inside the tubular body at an inner end with respect to the inside and outside of the housing. gas mask. The cylindrical body has a length smaller than the depth of the housing, and the outer surface of the cylindrical body and the end surface of the observation window with respect to the inside and outside of the housing is included in a plane formed by the outer shell of the housing. The gas mask according to any one of claims 1 to 4, wherein the gas mask is used. A device that is installed in an absorption can of a gas mask and displays the remaining capacity of a gas absorbent,
A hollow cylindrical body,
A substantially transparent observation window that is provided inside the cylindrical body and has a configuration for blocking a gas flow through a space in the cylindrical body,
A detecting agent provided on one side of the observation window in the space in the cylindrical body and having a different color before and after contact with a toxic gas to be removed by the gas absorbing agent. Remaining capacity display device.

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