Cooled table

Abstract

The invention relates to a table having a tabletop and including a refrigerating machine, at least one section of the tabletop being coolable by means of the refrigerating machine via a thermal contact; an upper vacuum chamber, which can be evacuated, for thermally insulating the thermal contact from a surrounding area of the table, said chamber connecting an upper face of the refrigerating machine facing the tabletop and the section to be cooled, and which has at least one flexible upper chamber section; a lower vacuum chamber, which can be evacuated, which is connected to a lower face of the refrigerating machine facing away from the tabletop, and which has at least one flexible lower chamber section; and a rigid stiffening structure, which is connected to the refrigerating machine via the flexible upper chamber section and via the flexible lower chamber section.

Claims

1. A table with a tabletop, comprising: a refrigerating machine, wherein at least one section of the tabletop is selectively cooled with the refrigerating machine via a thermal contact; a first vacuum chamber that is selectively pumped out for thermally insulating the thermal contact from an environment of the table, and a second vacuum chamber that is selectively pumped out, wherein the first and second vacuum chambers lie on opposite sides of the refrigerating machine with respect to a normal axis to a table surface of the tabletop.

2. The table according to claim 1, wherein the at least one section that is selectively cooled by the refrigerating machine is a cryogenic plate held in the tabletop.

3. The table according to claim 1, wherein the first vacuum chamber and second vacuum chamber are formed from a flexible material at least along the normal axis to the table.

4. The table according to claim 1, wherein the first vacuum chamber and second vacuum chamber are selectively pumped out through an external pump.

5. A table with a tabletop, comprising: a refrigerating machine, wherein at least one section of the tabletop is selectively cooled with the refrigerating machine via a thermal contact; a first vacuum chamber which is selectively pumped out to thermally insulate the thermal contact from an environment of the table, and which connects to an upper side of the refrigerating machine facing the tabletop and the section to be cooled; and a second vacuum chamber that is selectively pumped out.

6. The table according to claim 5, wherein the at least one section which is selectively cooled by the refrigerating machine is a cryogenic plate held in the tabletop.

7. The table according to claim 5, wherein the first vacuum chamber and second vacuum chamber are selectively pumped out through an external pump.

8. The table according to claim 1, wherein the first vacuum chamber and second vacuum chamber are selectively pumped out through the refrigerating machine.

9. The table according to claim 5, wherein the first vacuum chamber and second vacuum chamber are selectively pumped out through the refrigerating machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention and advantageous developments are illustrated in the attached figures by way of example. Identical features and features producing an identical effect are only sometimes provided with reference numbers. There are shown in:

(2) FIG. 1 a schematic sectional view of an embodiment example of the table according to the invention;

(3) FIG. 2 a schematic sectional view of a further embodiment example of the table according to the invention;

(4) FIG. 3 a schematic sectional view of a further embodiment example of the table according to the invention;

(5) FIG. 4 a schematic sectional view of a further embodiment example of the table according to the invention;

(6) FIG. 5 a schematic sectional view of a further embodiment example of the table according to the invention; and

(7) FIG. 6 a perspective view of a table according to the invention with an assembled hood.

DETAILED DESCRIPTION OF THE INVENTION

(8) FIG. 1 shows a schematic sectional view of a table 1 according to the invention, here an optical table 1. A tabletop 9 with a tabletop surface 2 lying on top of it is borne by table legs 4. Between each table leg 4 and the tabletop 9, one damping device 5 is arranged in each case. In one (or more) openings 3 in the tabletop 9 (in each case) a cryogenic plate 10 is rigidly secured by connection elements, with the result that an upper plate surface lies flush with the table surface 2. A flange (not shown) of a flexible upper chamber section of an upper vacuum chamber 50 is in mechanical and/or fluid connection to an upper side 26 of a refrigerating machine 20.

(9) Furthermore, the lower plate surface is in mechanical and thermal connection via a flexible element 22 made of a thermally conductive material such as copper, which can carry a flow of heat designed for efficient cooling of the cryogenic plate 10. The refrigerating machine 20 and the cryogenic plate 10 are thereby not rigidly connected mechanically and consequently are mobile against each other at least orthogonally to the table plane and vibration-insulated or vibration-damped from each other. The underside 27 of the refrigerating machine 20 is in mechanical and fluid connection to a flange (not shown) of a flexible chamber section 61 of a lower vacuum chamber 60. The upper vacuum chamber 50 and the lower vacuum chamber 60 lie on opposite sides of the refrigerating machine with respect to a normal 70 to a table surface 2 of the tabletop 9. An upper/lower vacuum volume 52/62 of the upper/lower vacuum chamber 50/60 can be evacuated by a pump stand (not shown) of the refrigerating machine 20 or via an external pump line 81 through an external pump stand (80) to an upper/lower pressure 50P/60P. A reinforcing structure 30 connects, on the side of the environment 100 and rigidly, the upper vacuum chamber 50 to the lower vacuum chamber 60, wherein the connection attaches above the upper flexible chamber section 51 and below the lower flexible chamber section 61.

(10) FIG. 2 shows a sectional view of a table 1 according to the invention, as already described in FIG. 1. The flexible upper chamber section 51 and the flexible lower chamber section 61 can be contracted and expanded along the normal 70. Through the upper/lower pressure 50P/60P, which acts on the upper/lower surface area 53/63 orthogonal to the normal 70, an upper force 50K and a lower force 60K are formed, which act on the refrigerating machine 20 in opposite directions along the normal 70. If the lower force 60K is equal to the upper force 50K, the refrigerating machine 20 is not moved against the tabletop 9. This thus-suppressed movement could for example induce vibratory disturbances for the experiments taking place on the tabletop 9 (experimental set-up not shown). The upper force 50K is equal to the lower force 60K when the quotient of the difference between the ambient pressure P and the lower pressure 60P P2 and the difference between the ambient pressure P and the upper pressure 50P P1 is equal to the quotient of upper surface area 53 A1 and lower surface area 63 A2, A1/A2=(PP2)/(PP1).

(11) FIG. 3 shows a sectional view of a table 1 according to the invention. The reinforcing structure 30 functions as a pressure regulation device 90, in order to equalize the upper pressure 50P and the lower pressure 60P. A cavity 31 of the reinforcing structure has outlets 32 into the upper vacuum chamber 50 and the lower vacuum chamber 60 respectively. This cavity 31 functions as fluid connection 91 for an upper gas flow 50F from the upper vacuum chamber 50 and a lower gas flow 60F from the lower vacuum chamber 60 to an external pump stand 80 or alternatively to a pump stand (not shown) of the refrigerating machine 20. It is also conceivable to design the pressure regulation device 90 as a component separate from the reinforcing device 30, for example as a flexible bellows tube.

(12) FIG. 4 shows a sectional view of a table 1 according to the invention. A cryogenic plate 10, to which the upper vacuum chamber 50 is flanged from below, is arranged on an opening 3 in the tabletop 9. The flexible upper chamber section 51 is flanged to the refrigerating machine 20 from above, for example by means of vacuum-technical of the upper vacuum chamber 50. In this embodiment the refrigerating machine 20 is supported in a rigid frame 28 which stands on the floor 82. From below, a flexible lower chamber section 61 of a lower vacuum chamber 60 is flanged to the refrigerating machine 20 or to the frame 28 rigidly connected thereto. The flexible upper chamber section 51 and the flexible lower chamber section 61 can for example be designed as a flexible bellows with annular connection flanges welded onto the ends in each case. The connection flanges can for example have an outer diameter of 6 OD (approx. 152 mm) as well as an inner diameter of the free opening of 5 ID (127 mm), 4 ID (101.6 mm) or 3.5 ID (89 mm). In the case of a typical setting of the upper/lower pressure 50P/60P in the upper/lower vacuum chamber 50/60, based on the atmospheric pressure (usually 1 bar) of the environment 100, an upper force 50K and a lower force 60K act equally in opposite directions, with the result that they compensate each other and compress the lower and upper flexible bellows. For an upper/lower surface area 53/63, which corresponds to the free inner diameter of the connection flange of the bellows of 101 (127) mm, then the upper/lower force 50K/60K is 80 (127) Newtons.

(13) FIG. 5 shows a sectional view of a table 1 according to the invention. In a modification of the embodiment represented in FIG. 4, the frame 28 is connected to the tabletop 9 via a number of damping devices 5.

(14) FIG. 6 shows a perspective view of a table 1 according to the invention with table legs 4, a tabletop 9 as well as an assembled hood 40, for receiving for example a sample to be examined (not shown). The refrigerating machine is arranged in a housing 25 under the table. In the upper region the hood 40 bears a viewing window 46 as well as further viewing windows 41 in the lateral region for inspection of its interior by an experimenter. Together with the tabletop 9 bordering it, the hood 40 defines a volume that can be evacuated, in particular via an external pump stand 80. The hood 40 is secured to the surface 2 of the table via a flange 44. Inside the hood 40 a sample can be examined via the windows 41, 46, wherein the sample can be kept in a cryogenic atmosphere.

(15) A person skilled in the art is also prompted by the invention disclosed here to combine features which are described in the context of different embodiments according to the invention, where technically possible.

LIST OF REFERENCE NUMBERS

(16) 1 Table 2 Table surface 3 Opening 4 Table legs 5 Damping device 7 Securing means 9 Tabletop 10 Cryogenic plate 20 Refrigerating machine 22 Thermal contact 26 Upper side 27 Underside 28 Frame 30 Reinforcing structure 31 Cavity 32 Outlet 40 Hood 41 Window 42 Cavity 44 Ambient temperature counterflange 45 Cryogenic counterflange 46 Viewing window 50 Upper vacuum chamber 50F Upper gas stream 50K Upper force 50P Upper pressure 51 Flexible upper chamber section 52 Upper vacuum volume 53 Upper surface area 60 Lower vacuum chamber 60F Lower gas stream 60K Lower force 60P Lower pressure 61 Flexible lower chamber section 62 Lower vacuum volume 63 Lower surface area 70 Spatial axis, normal 80 External pump stand 81 External pump line 82 Floor 90 Pressure regulation device 91 Fluid connection 100 Environment