EP0535385B1 - Breathing protection mask with inner half-mask and noxious matter indicator - Google Patents

Description

The invention relates to a respirator mask with an eye area through which the inhaled air flows and an indicator on a support for indicating the effectiveness of a protective device at the breath connection which retains the pollutant from the environment.

A respirator mask which has the features of the preamble of claim 1 is known from DE-C-962 313.

The respiratory masks mentioned are used to supply respiratory gas to people who work in or have to be in the breathing-damaging atmosphere. The air to be breathed is either cleaned using filters or freed of pollutants, or breathing gas is led from a bottle reservoir into the protective mask via a hose line. In respirator masks with a filter, indicators are attached to or in the filter, which either indicate the exhaustion of the filter material or indicate the breakthrough of pollutants, so that the mask wearer is warned in good time or can change the filter. In the case of compressed air breathing apparatuses, the monitoring of filter devices is not necessary, but it is just as important to monitor the tight fit of the full mask on the face area of the mask wearer in order to recognize whether there are any leaks at the sealing edge, which could lead to dangerous entry Allow polluted ambient air into the inhaled air. In this sense, the term breath connection means both the filter connection and the hose connection for a compressed air-operated respirator or the full mask itself.

In the known full face mask according to DE-PS 962 313, a colorimetric indicator is provided in the interior of the mask, which indicates the passage of harmful constituents from the environment into the interior of the mask by discoloring a detection reagent attached to the carrier in the presence of the pollutant to be monitored. In this known mask, however, it is disadvantageous that the extent to which leakage passages or filter exhaustion are indicated depends on the location of the indicator, depending on whether the air to be inhaled also sweeps past the indicator. In particular in the case of respiratory protection masks with an inner half mask, the breathing air guide is designed such that passage openings with associated check valves are provided between the outer mask space and the inner mask space, through which the inhaled air flows. In the case of an air flow directed in this way, the known indicator generally lies in the flow shadow and only enables an inaccurate, if any, indication of the pollutant that has passed through.

The invention is therefore based on the object to improve a respirator of the type mentioned so that a pollutant indication both in the event of leaks in the sealing zones of the mask or on the breathing gas lines in compressed air breathing apparatus and inadequate filter action is forced.

The object is achieved in that the wearer is arranged on an inner half mask of the breathing mask, and in that its access area containing the indicator is in positively guided flow contact with the inhaled air in the region of the passage openings connecting the eye space with the inner half mask space.

The advantage of the invention is that all inhaled air, regardless of the type of breathing connection, must inevitably be directed past the indicator. Such a pollutant display simultaneously detects the retention effect of the filter as well as the sealing effect of the mask edge and the tightness of the mask with its internals.

In order to be able to handle the indicator better for cleaning purposes or for service work, for example, it is expedient to provide a removable insert which, if necessary, can be removed from the mask body and reinstalled.

In a simple embodiment, the indicator consists of a detachable plaque which is attached to the inner surface of the half-mask body. It can be easily replaced and replaced by another if the detection of various pollutants is required.

In order to increase the variety of uses of an indicator, it is advantageous to design it as a chip-shaped carrier. This is equipped with a variety of display areas, which can either detect the same pollutant with different sensitivity or different pollutants on an indicator. When It should be understood in the form of a chip that, similarly to the semiconductor industry, where a chip accommodates various types of electronic assemblies, in the present case the chip-shaped carrier accommodates various types of detection systems in miniaturized form. In this way, the user is offered a variety of detection options in the smallest space and on a single carrier. The various display areas are provided with a colorimetric indicator, which on the one hand have openings through which the pollutant can reach the indicator, and on the other hand the areas are accessible for visual evaluation. In the simplest case, this is understood to mean the observation of the degree of discoloration by the user, who can determine a measure of the amount of pollutant or its concentration using comparison color standards. For an automatic evaluation, it is desirable to have the display areas scanned by an optical evaluation unit.

A suitable form of the display areas can be seen in the fact that they are designed as channels, the channel openings being to be regarded as access areas for the pollutant to be detected. At least one of the channel walls is designed as an optically transparent cover. This results in several colorimetric detection channels that are closed on all sides, but on the other hand have an inlet opening at their entrance or additionally at their channel exit through which the pollutant can flow either by diffusion or forcedly through a conveyor and the present pollutant via a length change in color of the indicator. The optically transparent channel wall allows either one Observe this discoloration with the eye or an evaluation by an optical evaluation unit.

Another useful embodiment of the chip-shaped carrier can be seen in the fact that the various display areas span the carrier in a network-like manner. They form a two-dimensional matrix, so to speak, whereby each individual area can either display a different display sensitivity for one and the same pollutant or one or more display areas can display different pollutants. The individual areas are at least partially exposed to the pollutant, or if a preselection is to take place in the sense that from a large number of pollutants only the one who can also be detected can access the display area, then this area is one for sealed the pollutant permeable and optically permeable cover.

A suitable optical evaluation unit contains only a few components, such as a light source and a detector, the light source throwing radiation of a suitable wavelength onto the indicator area, which is recorded by the detector either in transmission or in reflection. The light intensity measured in transmission or reflection gives a measure of the amount of pollutant or concentration absorbed by the indicator.

It is advantageous to mount the evaluation unit in the immediate vicinity of the carrier in order to constantly monitor the indicator area. Thus, when the discoloration progresses beyond a predeterminable limit value, an alarm device is activated activated, which informs the device wearer at an early stage that either a breakthrough of the pollutant through the breathing filter or a leakage has occurred at the sealing edge of the mask body.

In order to simplify handling, provision is made for the evaluation unit and the carrier to be accommodated in a common removable insert, this insert immediately having the passage openings and receiving the carrier in a position suitable for the evaluation and exposed to the inhalation gas. Carrier and evaluation unit thus form a common insert, which can be easily replaced for maintenance or cleaning purposes.

Fig. 1

Die Schnittdarstellung einer Atemschutzmaske mit einem Schadstoffindikator,

Fig. 2

Einen chipförmigen Indikator mit kanalförmigen Anzeigebereichen,

Fig. 3

Den Schnitt A-A durch den Träger nach Figur 2,

Fig. 4

Die Ansicht eines chipförmigen Trägers mit matrixförmiger Verteilung der Anzeigebereiche,

Fig. 5

Einen Schnitt durch den chipförmigen Träger nach Figur 4,

Fig. 6

Den Schnitt durch die Auswerteeinheit und den Träger als herausnehmbarer Einsatz.

An embodiment of the invention is illustrated by a schematic drawing and explained in more detail below.

Fig. 1

The sectional view of a breathing mask with a pollutant indicator,

Fig. 2

A chip-shaped indicator with channel-shaped display areas,

Fig. 3

The section AA through the carrier according to Figure 2,

Fig. 4

The view of a chip-shaped carrier with a matrix-like distribution of the display areas,

Fig. 5

4 shows a section through the chip-shaped carrier according to FIG. 4,

Fig. 6

The cut through the evaluation unit and the carrier as a removable insert.

In Fig. 1, a full mask (1) lies with its sealing edge (2) on the face of a mask wearer, which additionally has an inner half mask (3), which lies with its inner half mask space (4) around the nose and mouth area of the mask wearer. The full face mask (1) has a threaded connection (5) for a breathing filter (not shown), which, however, can also accommodate the connecting hose for the compressed air used as breathing air when using a breathing apparatus. A viewing window (6) enables eye contact with the surroundings. The inner half mask (3) carries a removable insert (7) which is buttoned at its edge (8) into a corresponding recess in the inner half mask (3). An evaluation unit (9) projects into the insert (7) and is positioned opposite in the immediate vicinity of a chip-shaped carrier (10) for the colorimetric display areas (11, 111), FIG. 3, FIG. 5, which indicate the pollutant. The insert (7) has passage openings (12, 112) for the inhalation gas which flows from the filter connection (5) via an inhalation valve (13) into the inner half-mask space (4). An exhalation valve (14) with a valve housing (15) enables exhalation along the exhale part (A) into the environment. If the respiratory protection filter is exhausted, so that the pollutant passes through the filter, the inhalation air along the inhalation recommendation (D) would pollutant through the through openings (112, 12) into the inner half-mask space (4), which inevitably on the carrier (10) flows past and discolored this. In the same way, a leak at the sealing edge (2) of ambient air according to the arrow (U) would allow the eye area (16) of the full face mask (1) to enter, which likewise inevitably passes the carrier (10) via the passage openings (12, 112) would enter the inner half mask space (4) along the flow arrow (L). In both cases, the pollutants carried during inhalation lead to a discoloration of the display areas on the carrier (10), which are continuously monitored by the evaluation unit (9) and lead to a visual display or a similar warning device when a predefinable threshold value is exceeded.

2 shows a chip-shaped carrier (10) with its channel-shaped display areas (11), as can be viewed, for example, by an observer or by the evaluation unit (9). The channels (11) are exposed with their channel opening (17) to the pollutant to be detected that is carried along with the inhaled air. The pollutants penetrate via the channel openings (17) via diffusion to the indicator (18) applied to the bottom of the channel (11) and there undergo a discoloration reaction with the indicator (18). The channels (11) are sealed with a permeable, optically transparent membrane (19) (Fig. 3). This seal (19) can be applied over all channels (11) or only over a part of these channels (11).

4 shows the chip-shaped carrier (10) with a matrix-like arrangement of display areas as display fields (111). In the form shown, the carrier (10) has nine such fields (111), each of which is assigned an indicator (118). In the middle display field (111) this indicator (118) is representative of points. The individual display fields (111) are separated from one another by partitions (20). Individual or all display fields (111) can be sealed with a membrane (119) that is permeable to the pollutant to be detected, but is optically permeable (FIG. 5).

6, the evaluation unit (9) is accommodated in the insert (7), which at the same time contains the carrier (10) in a receptacle suitable for this. The carrier (10) can be pushed into the receptacle along the arrow (21) and pulled out of it again, the attachment of the carrier (10) being produced by a clamp connection. The evaluation unit (9) has a light source (22) in the form of an LED, which emits light along the radiation arrow (23) onto the carrier (10), and specifically onto one or more display areas (11, 111). The reflected light (24) is recorded and processed by a detector (25). The electronic processing and the energy required to operate the evaluation unit (9) are all housed in the same housing for the evaluation unit (9). In the event that the discoloration of a display area (11, 111) has risen above a certain threshold value, the evaluation unit emits a warning signal, which occurs, for example, by the radiation source (22) flashing and thus giving the mask wearer a sign, either change the filter or check the mask fit. The passage openings (12, 112) are located in the insert (7), the passage opening (112) being provided with the inhalation valve (13), not shown.

Claims (11)

1. Protective respiratory mask having an eye area (16) through which the inspired air flows, and an indicator (18, 118), located on a carrier (10), for displaying the effectiveness of a protective device at the respiratory connection, which protective device holds back the pollutant from the surroundings, characterised in that the carrier (10) is arranged on an inner half mask (3) of the protective respiratory mask, and in that its admission surface, which contains the indicator (18, 118), is located in the region of the passage openings (12, 112) which connect the eye area (16) to the inner half mask area (4), in a manner such that said admission surface is in forcibly-guided flow contact with the inspired air.
2. Protective respiratory mask according to claim 1, characterised in that the carrier (10) is encapsulated in a shell-shaped insert (7), and in that the insert (7) can be buttoned into the inner half mask (3) so as to be gas-tight and has the passage openings (12, 112).
3. Protective respiratory mask according to claim 1 or 2, characterised in that the carrier (10) is in the form of a detachable disc, which is stuck on the inside surface of the half mask body (3).
4. Protective respiratory mask according to one of the claims 1 to 3, characterised in that the indicator (18, 118) is mounted on a chip-shaped carrier (10) which is provided with a plurality of display regions (11, 111), provided with a colorimetric indicator (18, 118), which on the one hand are exposed as an admission surface to the pollutant by way of openings (17), and the regions (11, 111) of which on the other hand can be scanned for an optical evaluation unit (9).
5. Protective respiratory mask according to claim 4, characterised in that the display regions on the chip-shaped carrier (10) are formed as ducts (11), the duct openings (17) of which form the admission surfaces, and of which ducts at least one duct wall is formed as a transparent cover (19).
6. Protective respiratory mask according to claim 4, characterised in that the display regions as display fields (111) are distributed in a matrix-like manner over the chip-shaped carrier (10).
7. Protective respiratory mask according to claim 6, characterised in that the individual regions (11, 111) are at least partially openly exposed to the pollutant.
8. Protective respiratory mask according to claim 6, characterised in that the individual regions (11, 111) are at least partially sealed with a cover (19, 119) which is permeable for the pollutant and is transparent.
9. Protective respiratory mask according to one of the claims 4 to 8, characterised in that the optical evaluation unit (9) has a light source (22) which illuminates the indicator region (11, 111), a detector (25) which accommodates the transmission/reflection radiation, and a measuring unit (9).
10. Protective respiratory mask according to claim 9, characterised in that the evaluation unit (9) is mounted in direct proximity to the carrier (10) so as to constantly monitor the indicator region (11, 111).
11. Protective respiratory mask according to one of the claims 4 to 10, characterised in that the evaluation unit (9) and the carrier (10) are accommodated in a removable insert (7) which on the one hand has the passage openings (12, 112) and on the other hand accommodates the carrier (10) in a position which is suitable for the evaluation and exposed to the inspired gas.

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