FI80203C - Method for sealing the water separator membrane in a gas analyzer - Google Patents

Description

1 80203

Gas analyzer water separator diaphragm sealing method.-Förfarande för tätning av vattenavskiljarens membran i en gasanalysator.

The invention relates to a method for sealing the porous membrane of a water separator of a gas analyzer. The invention further relates to a water separator for a gas analyzer with a porous membrane and an elastic seal.

For example, when using a porous membrane for water separation of a gas sample from a gas analyzer measuring breathing air, the problem is to seal the membrane so that tubular channels are formed on the surface of the membrane. Tubular channels are necessary to maintain the measurement speed.

A further problem is that when using rubber seals, the rubber materials must not come into contact with the gases used during anesthesia, because different gases are absorbed differently into different rubber materials. This causes measurement errors and slows down the measurement speed.

In known membrane water separators, the membrane is sealed only at its edges. This known solution has the following disadvantages: a large and incorrectly shaped volume, which causes a slowdown in the measurement. Another known method is to strongly seal the film by squeezing between the body parts. This method has the following disadvantages: The body parts must be made sturdy and supported by metal frames so that they do not warp under the effect of high compressive forces. The surfaces pressing the film must be very smooth and the compressive force must be dimensioned correctly so that the film does not cut.

The object of the invention is to provide a compaction method in which the above-mentioned disadvantages can be avoided. In this case, the separator can be made of, for example, plastic parts, which makes it cheap. Cheap price is a prerequisite because part is thought to be 2 80203 disposable.

In order to achieve the object and objects of the invention, the water separator sealing method according to the invention is characterized in that the film is sealed with a substantially larger elastic seal than the film separator. The water separator according to the invention is characterized in that the water separator is provided with a tubular channel on both sides of the membrane and that the membrane has an opening for a seal located substantially in the middle of the membrane.

In the following, the invention is illustrated with reference to the accompanying drawings, in which:

Figure 1 shows an elastic seal used for sealing.

Figure 2 shows a porous water separation film,

Figure 3 shows the seal and the porous film superimposed.

Figure 4 shows a section taken along the line I-I in Figure 3. The lower part 4 and the upper part 5 of the water separator have been added to the figure, shaved cut in the same direction as the membrane 2 and the seal 1.

According to Figures 1-4, the water separator comprises an upper part 5 and a lower part 4 and a water collecting vessel (not shown). A groove 9 is formed in the upper part 5, which together with the groove 6 in the lower part 4 forms a tubular channel for the sample gas. In addition, a gas space 10 is formed in the upper part 5 and gases 7 in the lower part, respectively, which form a space for the side flow gas. A porous membrane 2 is mounted between the upper part 5 and the lower part 4.

3 80203

An opening li for the seal 1 is formed in the membrane 2, substantially in the middle region of the membrane. As the seal 1, a rubber seal is preferably used, which is mounted on the membrane 2, preferably on the lower part 4 side. The seal 1 extends over the edge of the membrane 2 along the entire circumference of the membrane 2.

When using a water separator, the sample gas introduced into it is divided into two partial streams in the tubular channel 6.9 so that the anhydrous main flow gas passing through the membrane 2 passes through the upper channel groove 9 of the channel 6.9. in the channel groove 6. The side flow gas passes from the channel groove 6 through a water collecting vessel (not shown) to the gas space 7 and further through the membrane 2 to the gas space 10, from where it is led to the main flow through measuring sensors (not shown). The gas flowing in the space 7 is at a different pressure than the gas flowing in the channel groove 6 and their mixing with each other is prevented by the part in the opening 11 of the seal 1. Leakage of gases is prevented by a part of the seal 1 extending over the edge of the membrane 2. The gas sample, especially the part passing through the channel groove 6, must not come into direct contact with the rubber seal. This is prevented by forming edge barriers 3 in the lower part 4 of the water separator on the seal 1 side, which prevent the gas sample from coming into contact with the rubber seal. The edge walls 3 are formed at least on the edge of the channel groove 6, and preferably also on the edge of the gas space 7. The space 8 is intended for the connecting members of the upper part 5 and the lower part 4, preferably a screw connection, and does not require the use of edge barriers. In state 8 there is usually a normal external pressure. The seal 1 is preferably dimensioned so that its height exceeds the height of the edge walls 3 and is preferably at least as high as the common height of the edge wall 3 and the membrane 2.

Claims (11)

A water analyzer water separator comprising a gas channel arranged in a body part with a porous membrane, characterized in that the membrane (2) is arranged between the channel parts (6, 9) opening against the membrane (2) and the channel part (s) (6, 9) is sealed at its edges against the membrane (2) by a seal (1), which seal (1) extends over the edge of the membrane (2) along the entire circumference of the membrane (2), further sealing the gap between the body parts (4, 5) outside the membrane (2) prevent it. Water separator according to Claim 1, characterized in that gas flow chambers (7, 10) on different sides of the membrane (2) are formed in the body part (4, 5) and are in flow communication with the duct part (6). Water separator according to claim 2, characterized in that the membrane (2) is provided with an opening (11) arranged between the duct parts (6, 9) and the gas flow chambers (7, 10), the seal (1) being located in the opening (11). ) between the body parts (4, 5). Water separator according to claim 3, characterized in that the opening (11) is substantially in the middle of the membrane (2) and the channel parts (6, 9) are arranged partially surrounding the opening (11). 4 80203 Water separator according to one of Claims 1 to 4, characterized in that the channel parts (6, 9) are formed by a groove (6) formed in the lower part (4) of the water separator and by a groove (9) formed in the upper part (5). 5 80203 Water separator according to one of Claims 1 to 5, characterized in that the seal (1) is separated from the gas sample by means of edge barriers (3). Water separator according to Claim 6, characterized in that the edge walls (3) are formed in the part (4) on the seal (1) side of the water separator on the edge of the groove (6). Water separator according to Claim 6, characterized in that the edge barriers (3) are further formed in the part (4) on the seal (1) side of the water separator on the edge of the gas space (7). Water separator according to one of Claims 1 to 8, characterized in that the seal (1) extends in the height direction beyond the plane formed by the edge ridges (3). Water separator according to one of Claims 1 to 9, characterized in that the height of the seal (1) is at least equal to the common height of the edge walls (3) and the membrane (2). Water separator according to one of Claims 1 to 10, characterized in that the seal (1) is an elastic seal, preferably a rubber seal. 6 80203 Patentkray