DE2259808A1 - EASILY DISASSEMBLY DIFFUSION PUMP - Google Patents

Description

Easily dismantled diffusion pump

The invention relates to a diffusion pump that is used for cleaning the elements forming the pump can be easily dismantled.

As is known, the diffusion pumps essentially comprise an oil container above a heating element or a heater, above which a diffuser is arranged, which helps to push the oil sumps against the forming the pump body and enclosing the oil container to spin or spray the cooled wall. These vapors condense on this wall before they move back in inserted into the oil container.

In order to avoid traces of oil vapor entering the evacuated Volumes are introduced, one usually assigns directly, Above the pump a condensation device, which is formed by a water-cooled baffle and above the one Liquid nitrogen trap or a liquid nitrogen trap arranged is.

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Also known: the cooled wall surrounding the oil tank, which is exposed to the incessant bombing by the Clay is exposed to the vapor flow of entrained molecules be cleaned very carefully at fairly regular intervals as well as the deflection training and the plus-nitrogen trap. This necessarily results in very frequent and fairly long dismantling work, which in considerable Way burden the running costs of a facility equipped with a diffusion pump.

The invention is now intended to propose a pump configuration in which the different ones are arranged one above the other Elements can be dismantled very easily so that the inner wall of the pump body is then easily accessible and their cleaning is easy to accomplish. In addition, the various pump components that come from the inside removed from the pump body, must be cleaned with great care.

The invention is thus based on an easily dismantled diffusion pump arrangement in which a cylindrical The pump body, which is divided by means of its cover, is divided into slides one flange blocked 1st, one on the bodon of the pump body arranged oil tank is provided over which its diffuser builds, as well as two condensate arranged one above the other ion elements which are arranged at the level of the discharge pipe and are formed by a winged rib Deflector plate, a protective screen and one with wing ribs Liquid nitrogen all. The invention is characterized by this that the connection between the pump body and the elements forming the pump is designed so that a

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Extraction of these elements by simple! Translation to becomes possible after loosening the flange

It follows from this that it is sufficient to have such a condensation element to disconnect it from the cold source without the need to discard cooling liquid lines. Due to this measure, it is sufficient that in the pump body elements contained in a simple translation olien awsssusetiseiif to completely disassemble the pump or dismantle '. There then remains an inside smooth cylindrical element which forms the inner part of the body of the pump. Such an element is very light to clean.

It is easy to see that the creation of thermal contact is the low thermal impedance between the cold source and the the rib plate makes certain precautions necessary. The surfaces in contact are fully aligned. In ttbrjspn the contact can be improved by the pressure of a peder if the forces of gravity prove to be insufficient should prove.

In the case of pumps of the usual type, in which the deflector is cooled by a water circulation, considerable inconvenience can occur when the water circulation is used interrupted even accidentally. In the upper part of the pump the action of the plasmic nitrogen trap becomes predominant and the water of the deflector can freeze. This leads to cracks in the water pipe, which leads to irreparable damage, especially in the diffusion pump by mixing the water with oil.

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Such incidents are avoided if the deflection or impact device is cooled by heat conduction. The cold source of the deflection device is preferably built into the wall of the pump body in such a way that it does not protrude after the pump has been installed.

An analog device can be used to implement the liquid nitrogen all or the liquid nitrogen longer to be realized; the surface of the in contact with the surface The rib plates standing next to the cold source are then considerably larger and the cross-section of the conductive ribs is considerably higher.

For certain forms of execution it will be preferred to use the The circle of liquid nitrogen all to be assigned to the cover of the pump, this makes it possible, as before, to keep the nitrogen lines connected to the outside of the pump. The effect of the trap is then even stronger without causing any dismantling difficulty. If you lift the lid off, the trap and liquid nitrogen storage are attached to it, pulled out at the same time.

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An example embodiment of the invention is now intended will be explained in more detail with reference to the accompanying drawing, which schematically shows a section through an embodiment a diffusion pump according to the invention shows »in which the impact or deflection device is cooled by heat conduction, while the liquid nitrogen is all connected to the lid. The single figure shows the pump body 1, surrounded by a water-cooled KUhlschlage 2, above which a the cold source of the deflection device 9 forming memory 3 is arranged.

This device itself consists of an arrangement of ribs such. B. 4 ·, with which thermally and mechanically the Plügelrippen such as 7 and 8 are connected to form an optically dense screen. These ribs 4 are at the two ends provided with a directional rib plate 5, which is against a also completely flat surface element 6 of the upper Part of the memory 3 is supported.

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The oil container 20, over which its diffuser 21 is arranged, is separated from the deflection device or the deflection plate by a protective screen 22 which is mechanically and thermally connected to the deflection device 9. The deflection device (baffle) is arranged essentially at the level of the line 23 and connects the pump to the volume to be evacuated via a slide (not shown).

The cover 10, which closes the pump column, is arranged above the deflection device. This cover is with the pump body 1 connected by means of a flange 11 provided with a seal, not shown, arranged in a circular groove 12.

The liquid nitrogen scavenger is after the described execution form 24 supported by the cover 10. The liquid nitrogen tank 13 constituting the cold liquid nitrogen source is extended downwards via lines like 1Θ and 19, which circular wing ribs such as B. 16 wear, which are in close thermal contact with these lines.

In the upper part of the storage tank is extended by two lines: a feed line closed with a plug 17 and a delivery line 14.

One can see that the formation of the connection between the various Components make it very easy to dismantle the pump: take the cover 10 after releasing the flange

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whether, the condensation device is removed at the same time, which is formed by the liquid nitrogen trap, the is mechanically connected to it. So you only need the distance through the deflection or guide device (baffle) to pull out the condensation device formed. This dismantling is also very easy, see the deflection device simply supported on their cold storage 5, the thermal connection being extremely favorable due to the contact ! between the directed or cut out rib plate 5 and the completely flat surface of the memory 3 made became. No screw or rivet connection between the deflection device and the pump body is made.

When lifting the Ural steering device one pulls the at the same time Protective screen 22 out, which protects the deflection device 9 against direct irradiation through the diffuser 21, the however, it is connected to the ribs 4 of the deflection device 9. The diffuser 21 is therefore accessible. You can also use the diffuser 23 punch pull out the oil container 20. The pump body 1 is then completely free.

It can be seen that in the device according to the invention none the Konäemaationeeleinente screwed against the pump body or riveted.

A preferred embodiment has been described for implementation the measure according to the invention. Numerous modifications can be made to this embodiment within the framework of the invention, however, can be made. So you can in particular install the nitrogen reservoir in the upper part of the wall of the pump body and you can then the vane ribs of the liquid nitrogen trap by conduction of the thermal with these and with dom. Storage connected trusses cool ..

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Claims (5)

PATENT CLAIMS Easily dismantled diffusion pump, in which one is held in place by a tarpaulin closure Cover closed pump cylinder body on an oil container the bottom of the pump body is arranged and above this a diffuser is attached, and in which two superimposed on each other Condensation elements are attached at the level of the vacuum line »whereby these are guided by a deflection device with spiral ribs and Protective screen and a liquid nitrogen trap provided with wing ribs are formed, characterized by a Connection between the pump body (1) and the components forming the pump in such a way that the components can be pulled out simple translation upwards is possible after loosening the fastening of the flange (21). 2. Diffusion pump according to claim 1, characterized in that the memory (3) fixed to the lower condensation element connected to the pump body C1; and that the thermal The connection between the deflection device (9) and the accumulator is simply due to the force of gravity between the heavily polished flat surfaces the rib plate (5) and the surface (6) of the memory (3) is ensured such that this capacitor element can be removed by simple translation upwards. 3 * diffusion pump according to one of claims 1 or 2, characterized in that the upper Kondenasfcionselement mechanically and is thermally connected to the liquid nitrogen storage (13), which itself is mechanically attached to the cover (10) in such a way that by lifting the cover this condensation element is in trans- - 8 ~ 30982WCU01 225980B -for- ! ation is taken upstairs. 4. Diffusion pump according to claim 3 _f, characterized in that the pump body is formed from two cylindrical, equiaxed elements, one of which is above, the other is and at the level of the discharge line (23) via a
circular, horizontal shoulder (6), which forms the upper part of the Sepichers (3), is connected. 5. Diffusion pump according to one of claims 1 to 4, characterized in that the wing ribs of the condensation elements mechanically and thermally with the one from a heat very good conductive metal existing ribs are connected; and that they are kept in close thermal contact with the surface of the corresponding cold source. 309824/0401 Blank page