RU1625256C - Gas neutralizer of ion beam - Google Patents

Abstract

The invention relates to the creation of gas targets in ion beam neutralizers. A chain of the invention is to increase gas efficiency by reducing leakage of neutralizing gas along the beam, providing a continuous mode of operation. The device comprises a recharging chamber with openings for the passage of the beam, nodes for supplying and collecting a transverse stream of neutralizing gas and closed loop of its circulation through the recharge chamber, receiver with leakage. What is new in the device is that counter-mounted vacuum molecular pumps are used as supply and withdrawal units. Each pump has two spherical rotors of perpendicular rotation, the central rotor of each pump contains one annular groove. the inlet pipe flanges are connected by a recharging chamber and mounted on the spherical pump housings against the inlet windows of the external rotors, the selection pump is equipped with a sealing insert and installed by the suction end of the pumping groove of the central rotor diagonally tangentially intersecting the recharging chamber, to the discharge end of the groove of the central pump rotor; in this case, the axes of the central rotors of the feed and take-off pumps are parallel to the axis of the holes for the passage of the beam and the outlet pipes of the feed and take-off pumps are connected between each other by a pipeline to which a receiver is connected through a leak. This provides a closed gas circulation in the converter, which sharply reduces the gas flow from the receiver, reduces gas leakage along the beam and increases the continuous service life of the catalyst 1 il

Description

FIELD OF THE INVENTION

The purpose of the invention is to increase the gas efficiency of the neutralizer by decreasing the leakage of the neutralizing hage along the beam and to ensure continuous operation.

The drawing schematically shows a gas ion beam neutralizer in section.

The neutralizer consists of a recharging chamber 1 with holes 2 for the passage of the ion beam (the beam is normal to the plane of the drawing), Camera 1 is connected by flanges 3 to the inlets of the suction pumps 4, 5 of the neutral gas supply and selection, respectively, which are used as molecular vacuum pumps with two spherical rotors rotating around mutually perpendicular axes. Flanges b, - 7 of the pump inlets on the housings 8.9 are located against the inlets of the external rotors 10, 11, Flanges 12, 13 of the pump outlets are interconnected by a pipe 14 of a closed gas circulation circuit, to which the receiver 15 is connected via trickle 16. The selection pump 5 is equipped with a sealing insert 17 that prevents the gas from moving by the rotor 18 from the outlet to the inlet of the pump 5. The movement of gas from the inlet to the outlet of the pump 5 oruopa or flange 7 to the flange 13 is carried out by a part of the pose 19 of the central rotor 18, which is covered by the surface wise ogora 11 with helical grooves 20. The 4 pozzi pump, containing a sealing insert, moves the gas from its exit to the outlet (from flange 6 to flange 12) by the honor of the groove groove 21 of the central rotor 22, which is covered by the surface of the outer rotor 10 with helical grooves 23, and from the exit to the inlet of the pump, part of the annular groove 24, Pumps 4, 5 are mounted towards each other, while the ends of the parts of the grooves 19, 24 of the central rotors 18, 22 facing the recharging chamber 1 have a common tangent, shown in broken line in the drawing passing through perezar chamber 1 and at a right angle the intersecting axis of the hole 2 for the passage of the beam, and this salt is parallel to the axes of the central rotors 7.2, 18 and 4 pumps 5. The arrows indicate the directions of rotation of the rotors 18 and 22,

Gas Converter operates as follows.

First, the central and outer rotors 22, 18. 10, 11 of the pumps A, 5 are driven around mutually perpendicular axes. Upon reaching the rated speed, the rotary / neutralizer is filled with gas from the receiver 15 through an adjustable leak 16. The gas flows through the pipe 14 and enters through the flanges 12, 13 on

exits of the pumps 4, 5. Gas penetration through the extraction pump 5 from the outlet to its entrance is prevented by the oncoming movement of the walls of the part of the groove 19 of the central rotor 18, the sealing insert 17, the gas drift by the helical grooves 20 of the outer rotor 11 from the inlet to the outlet of the pump. The gas supplied to the suction end of the groove 24 of the central rotor 22 of the supply pump 4 is accelerated by this rotor, and when it leaves

5, the surface of the outer rotor 10 is tangentially torn off and intersects the recharging chamber 1 along the dotted line in the drawing. The diameter of the neutralizing gas flow is determined by the cross section

0 groove 24, forming a stream. The stream passing through the chamber 1 penetrates deeply into the tangentially mounted suction end of the groove part 19 of the central rotor 18 of the selection pump 5 and is withdrawn by the rotor

5 1 s to the outlet of the pump 5, from where through the outlet flange 13 and the pipe 14 again flows to the flange 12 of the feed pump 4, and from there to the suction end of the groove 24 of this pump. - there is a pose 21 of the Central rotor 22 and

0 screw grooves 23 of the external rotor of the supply pump 4, as well as screw grooves 20 of the external rotor 11 of the selection pump 5 improve the vacuum in the recharge chamber 1, which reduces the braking of the neutralizing

5 threads.

The vacuum is enhanced by the compactness of the recharging chamber 1, achieved due to the parallelism of the axes of the central rotors 22, 18 of the axis of the holes 2

0 for the passage of the beam,

Upon reaching a predetermined value of the neutralizing flow, the flow 16 reduces the gas supply from the receiver 15 to a different gas leakage through the openings of the chamber 1. The taking into account the remoteness of the holes 2 of the chamber 1 from the flows, as can be seen from the drawing, it can be argued that the leakage of the neutralizing gas is negligible . After filling the camera

0 recharging gas into it through holes 2 serves an ion beam.

The described embodiment of the converter makes it possible to obtain an almost closed circulation of the gas supply in the converter, which significantly reduces gas consumption in comparison with the prototype and increases the time of continuous operation of the converter. Due to the high rotation speeds of the ball rotor of the pump 4, and also because three of the four walls of the groove 24 are

along it and transmitting their motion to the gas, higher than in the prototype speeds of supplying a stream of neutralizing gas to the recharging chamber are achieved with respect to the average speed of thermal motion of the constituent molecules. Both in the proposed converter and in the prototype, the neutralizing gas flow when passing through the recharging chamber is slowed down due to the imperfection of the molecular selection mechanism, when a part of the incident flow molecules is reflected towards it from the cryopanel surface or from the input part of the selection pump, and due to flow inhibition reflected from the walls of the recharge chamber by molecules that left the flow due to mutual collisions.

In the proposed converter, these negative factors are weakened by the installation of the suction end of the groove part 19 of the selection pump tangentially to the downstream flow, as well as by the mutual parallelism of the axes of the central rotors of 22.18 supply and selection of the beam axis. The tangent installation provides deep penetration of the molecules of the incident stream of the neutralizing gas so the suction end of the groove 19, from where they almost have no possibility

return to the recharge chamber due to drift by the groove walls of the central horn 18, which are fast moving along the channel 18. When installed tangentially, the axis parallelism ensures not only beam perpendicularity to the flow, but also compactness of recharge chamber 1, when the ratio of the area of the stationary walls of the recharge chamber to the cross section m of suction channels of pumps 4 and 5 is minimal, which minimizes the inhibitory effect of the walls of the chamber 1 of the charge. Due to the higher relative flow rate in the chamber 1, due to the proposed mutual installation of the supply and extraction pumps, the leakage of the neutralizing gas is reduced compared to the prototype along the beam of fast particles. Reducing gas leakage along the ion beam, reducing its flow rate and ensuring continuous operation increase the gas efficiency of the converter.

(56) Goodman R.K. and others. An ion beam neutralizer with a transverse stream of neutralizing gas. - Devices for scientific research, 1971, No. 9, Art. 76.

D chkov B.A. et al. Lithium ion neutralizer. - Devices HDR scientific research, 1974, No. 2, p. 35.

Claims (1)

The claims A GAS ION BEAM NEUTRALIZER, comprising a recharge chamber with openings for the passage of the beam and nodes for supplying and selecting a lateral hole for passing the beam of the neutralizing gas stream connected to it from two sides, connected to a closed loop pipeline of neutralizing gas, characterized in that in order to increase the gas efficiency of the converter by reducing the leakage of the neutralizing substance along the ion beam and to ensure continuous operation, the supply and selection units They are in the form of counter-mounted i vacuum molecular pumps, each of which consists of an external and central spherical rotor with mutually perpendicular axes of rotation, while the central rotors contain one annular groove, the selection pump is equipped with a sealing insert, and the pumps are installed so that the common tangent to the groove surfaces of the central rotors of both pumps intersects the axis of the holes for the passage of the ion beam at a right angle, and the circulation circuit is connected to the pump housings opposite the exit windows of the outer rotor and the receiver is provided with a leak valve. U / f. 0 Nbcczz