Device for examining an atmosphere and use of the device

Abstract

The invention relates to a device for examining an atmosphere, comprising an atmosphere analysis chamber and a cryocooler, which is thermally coupled to the atmosphere analysis chamber for cooling the atmosphere analysis chamber. The invention further relates to the use of the device for examining an atmosphere, in particular the composition of an atmosphere.

Claims

1. A device for examining an atmosphere comprising: an atmosphere analysis chamber; and a cryocooler which is thermally coupled to the atmosphere analysis chamber in order to cool the atmosphere analysis chamber, characterised in that an optical particle counter is attached to the atmosphere analysis chamber.

2. The device according to claim 1, characterised in that the atmosphere analysis chamber has two inlets in particular arranged on opposite sides of the atmosphere analysis chamber.

3. The device according to claim 1, characterised in that the cryocooler has a cooling head which is thermally coupled to the atmosphere analysis chamber.

4. The device according to claim 1, characterised in that the device has a preferably closed outer chamber surrounding the atmosphere analysis chamber.

5. The device according to claim 4, characterised in that the outer chamber is under negative pressure.

6. The device according to claim 4, characterised in that the cooling head of the cryocooler is arranged inside the outer chamber.

7. The device according to claim 3, characterised in that the cooling head of the cryocooler is thermally coupled to the atmosphere analysis chamber by means of one or more thermally conductive connections, wherein the one or more thermally conductive connections are preferably arranged within the outer chamber.

8. The device according to claim 1, characterised in that the wall of the atmosphere analysis chamber and/or the wall of the outer chamber is made of stainless steel, aluminium or copper.

9. The device according to claim 1, characterised in that the wall of the atmosphere analysis chamber has a coating on the inner side and/or on the outer side.

10. The device according to claim 1, characterised in that one or more heating elements are affixed or thermally coupled to the atmosphere analysis chamber.

11. The device according to claim 3, characterised in that one or more heating elements are affixed or thermally coupled to the cooling head.

12. The device according to claim 4, characterised in that a shield is provided inside the outer chamber to reduce thermal radiation between a wall region of the outer chamber and a wall region of the atmosphere analysis chamber.

13. The device according to claim 12, characterised in that the shield is thermally coupled to a cryocooler for its cooling.

14. The device according to claim 1, characterised in that a sensor or analytical apparatus for analysing the atmosphere is arranged in or connected to the atmosphere analysis chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further features and advantages of the device and its use are described in the following embodiments, wherein reference is made to the enclosed drawing.

(2) In the Drawing

(3) FIG. 1 shows a first device with a cooling-circuit cooling system,

(4) FIG. 2 shows a second device with a cooling-circuit cooling system,

(5) FIG. 3 shows a first embodiment of the device with a cryocooler,

(6) FIG. 4 shows a second embodiment of the device with a cryocooler.

(7) FIG. 1 shows a device for examining an atmosphere with an atmosphere analysis chamber with a cooling-circuit cooling system in schematic sectional view.

(8) Device 2 comprises an atmosphere analysis chamber 4 with two opposite inlets 6a-b and a closed outer chamber 8 surrounding them. In this case, atmosphere analysis chamber 4 and the outer chamber 8 are rotationally symmetrical to axis 10, which runs through the two inlets 6a-b.

(9) Atmosphere analysis chamber 4 and outer chamber 8 of the device are formed by an inner container 12 and an outer container 14 surrounding it Wall 16 of inner container 12 forms the wall of atmosphere analysis chamber 4. Wall 16 also forms the wall of outer chamber 8 together with wall 18 of outer container 14.

DESCRIPTION OF THE INVENTION

(10) To cool the atmosphere analysis chamber 4, a pipe coil 20 is mounted on the inner container 12, through which a cooling liquid flows during operation. To this end, a coolant feed line 22 and a coolant return line 24 are provided, via which the pipe coil 20 is embedded in a cooling circuit.

(11) FIG. 2 shows a second device for examining an atmosphere with an atmosphere analysis chamber with a cooling-circuit cooling system in schematic sectional view.

(12) Device 32 has a similar structure to device 2. Components that correspond to one another are marked with the same reference signs.

(13) Device 32 differs from device 2 in that cooling for the atmosphere analysis chamber 4 is provided by a tempering gas from a cooling circuit instead of the pipe coil 20 through which cooling liquid can flow.

(14) To this end, an inlet 34 and an outlet 36 for a tempering gas of a cooling circuit are provided on the outer container. During operation, a cooled tempering gas 38 is fed through inlet 34 into the outer chamber 8 which, after flowing through the outer chamber 8, exits outer chamber 8 through outlet 36 again. The tempering gas cools wall 16 of inner container 12 and thus the atmosphere analysis chamber 4.

(15) Devices 2 and 32 allow cooling of the atmosphere analysis chamber 4. However, cooling by means of a cooling circuit using cooling liquid as in device 2 or tempering gas as in device 32 has proven to be quite complex and maintenance-intensive.

(16) FIG. 3 now shows a first embodiment of the device with a cryocooler in schematic sectional view.

(17) Device 52 comprises an atmosphere analysis chamber 54 with two opposite inlets 56a-b and a closed outer chamber 58 surrounding it, which is under negative pressure, preferably under vacuum. Atmosphere analysis chamber 54 and outer chamber 58 are rotationally symmetrical to axis 60, which runs through the two inlets 56a-b.

(18) Atmosphere analysis chamber 54 and outer chamber 8 of the device 52 are formed by an inner container 62 and an outer container 64 surrounding it Wall 66 of the inner container 62 forms the wall of atmosphere analysis chamber 54. Wall 66 also forms the wall of outer chamber 58 together with wall 68 of outer container 64.

(19) A cryocooler 70 is provided to cool atmosphere analysis chamber 54. Cryocooler 70 can be a Gifford-McMahon cryocooler, a pulse tube cryocooler or a Stirling cryocooler. The cryocooler is preferably single-staged. The cryocooler has a cooling head 72, which is located in the outer chamber 58. Cooling head 72 is thermally coupled to the wall 66 via a thermally conductive connection 74 by means of a thermal link 76 and thus to the atmosphere analysis chamber 54. The thermally conductive connection 74 can, for example, be a copper cable wire or copper wire meshwork. The thermal connection 76 can be a screw connection, a solder connection or a clamp connection. In FIG. 3, cooling head 72 is connected to wall 66 in the region of the inlet 56a. Wall 66 has a copper coating on the inside (i.e. on the side located inside the atmosphere analysis chamber 54) and/or on the outside (i.e. on the side located in the outer chamber 58), which results in a more even tempering of atmosphere analysis chamber 54.

(20) FIG. 4 shows a second embodiment of the device with a cryocooler in schematic sectional view.

(21) Device 92 has a similar structure to device 52. Components that correspond to one another are marked with the same reference signs.

(22) Device 92 differs from device 52 in that cooling head 72 is thermally coupled via several thermally conductive connections 94a-c by means of respective thermal connections 96a-c to wall 66 and thus to the atmosphere analysis chamber 54. In FIG. 4, cooling head 72 is connected to wall 66 in the region of inlet 56a, in the region of inlet 56b and in a region lying in-between.

(23) Within outer chamber 58, between wall 66 of inner container 62 and wall 68 of outer container 64, there is a shield 98 arranged that reduces the transmission of thermal radiation from wall 68 to wall 66. For an even more effective reduction of thermal radiation transfer, shield 98 can be thermally connected to cooling head 72.

(24) One or more controllable heating elements may be provided on cooling head 72, on the thermally conductive connections 94a-c and/or on wall 66, which heating elements allow better control and/or regulation of the temperature of atmosphere analysis chamber 54.

(25) It has been found that the use of a cryocooler 70 enables low-maintenance and efficient cooling of atmosphere analysis chamber 54. Particularly efficient cooling can be achieved with the configurations according to devices 52 and 92. A measuring instrument 78 may be used for measuring and recording pressure conditions and/or temperatures in the devices 52 and 92.