SU836090A1 - Device for dispersional investigation of bacterial aerosols - Google Patents

Description

The invention relates to devices for the dispersion of bacterial aerosols. For studying the dispersion of bactericidal aerosols on solid nutrient media, a device is known. fl. The device comprises a housing with absorbing and exhausting pipes and cascading elements placed inside the housing and containing annular bulkheads that divide the cascading element into zones, there are holes in KOTOptjx, and the holes are reduced depending on the distance of the zone from the center . The disadvantage of these devices is the accumulation of aerosol particles and the nutrient medium in the zone of their exit from the holes, caused by the large amount of particles leaving the hole compared to their subsequent velocity in the area after the hole. Due to this accumulation, aerosol particles: stick together with each other, which causes smudge when determining their size and quantity. In addition, some particles are deposited in the wall 4 of each hole of the cascadeping element of the element before passing through the verstier, and this also causes an error in calculating the amount of aerosol particles. The aim of the invention is to increase the accuracy of the determination of the size and number of particles by ensuring uniform distribution on the trapping surface. To achieve this goal, a device is proposed that includes a housing with suction and exhaust connections, a cascading element with annular zones attached to the suction connector, made in the form of a plate with annular shapes, with grooves at the edges of which are flanged, with attached rings Together with them there are slots connecting the cascading zones and the bacterical cup with the annular sealing element between its end and the hull edge. FIG. 1 shows a general view of the devices in section; in fig. 2 is a bottom view of a cascading element. The device includes a housing 1, in the center of which a suction nozzle 2 with a sealing nut 3 and a bell 4 is fastened to the thread.

parts of the suction nozzle are screwed cascading element 5 in the form of a plate, which contains the suction nozzle 6 with a tapered hole to help smooth the direction of the jet in the first cascading zone, annular grooves 7 and annular flanges 8 located near the grooves.

The annular partitions 9 are interconnected by radial fusions 1, with an extreme fixing ring 11 which fits tightly onto the cascading element 5 and ensures the exact position of the annular partitions 9 relative to the annular grooves 7. The annular partitions 9 and the radial partitions 10 are bolted to the cascading element 5, which at the same time perform the function of adjusting bolts facing the bottom of the cup. In the ring, the grooves 7 enter the upper parts of the annular partitions 9, which form on one side the entrance slits 13 of the same size, and on the opposite side the output slots 14 of decreasing size as they move away from the center to the periphery.

The cascading element 5 enters the bacterial cup 15 with a layer of nutrient medium 16, which is fixed by the clamping ring 17 and clamped by folding bolts 18 entering the slots 19 of the housing 1 with nuts 20. The upper edge of the bacterial cup presses the rubber gasket 21 attached to the bottom housing in a special groove 22 and prevents the passage of air into the bacterial. a cup.

On the upper part of the housing 1, an air suction chamber 23 is sealed, containing an opening 24 for suctioning air from the bacterial cup and an outlet 25 dp connecting the device to the discharge unit.

The device works in the following way.

Turning the socket 4 clockwise reels the annular partitions 9 of the cascading element 5 into the nutrient medium layer 16. At the same time, four cavities A, B, C, and D are separated from each other by the ring, which communicate with each other only through slots 13 and 14 cascading elements 5. The device is connected to the source of the discharge by means of the outlet 25. Investigate the air through the suction inlet 2 enters cavity A and hits the nutrient medium, leaving larger parts of it. Then the air flows smoothly from age to speed through the gaps

13 and 14, changes direction, referring to the annular rim 8, and, the passage of the cavity c, B and D, is directed through the opening 24 of the chamber 23 to the suction nozzle 25. 5 The air stream from each slit 14 comes out at a greater speed than from the previous slot, since the output slots decrease as they move away from the center to the periphery, and this ensures the distribution of particle size in separate cascading zones. Due to the presence of the bead 8, the jet is directed to the surface of the nutrient medium and due to the resulting turbulence behind the bead, aerosol particles of a certain size are evenly distributed on the surface of the nutrient medium in each aerosol deposition zone.

Due to the fact that in the proposed

In the aerosol passage device, slots of reduced dimensions were used, rather than holes, as is the case in the prototype, the deposition of particles on the wall containing holes when they enter the cascading zones is eliminated, which increases the accuracy of counting the number of particles.

In the study of physical aerosols, glass or metal and the like are placed in the cup along with the nutrient medium. plates corresponding in shape and diameter of the bacterial dish, and on concentric partitions cascading. element wear special rubber o-rings.

Claims (1)

1. USSR author's certificate No. 278967, cl. From 12 to 1/10, 1969. 89c 7J fJf Phage. I / J