JP2512014Y2 - Vacuum pumping structure of the annular coupling cavity type acceleration cavity - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is an AC that accelerates charged particles by high-frequency power.
S Annular Coupled Structure (hereinafter referred to as ACS) type vacuum evacuating structure.

[Conventional technology]

Conventionally, as shown in FIG. 3, the ACS type acceleration cavity has a segment pair 3 consisting of a pair of front and rear segments of a disk-shaped front half segment 1 and a rear half segment 2 each having the same diameter and thickness. It is assembled by connecting a plurality of pairs coaxially and airtightly in tandem.

A front half acceleration cell 4 is recessed in the center of the rear surface of the front half segment 1, a front and rear coupling cell 5 is coaxially recessed in the front outer periphery, and a front center of the rear half segment 2 is formed in the center. The second half acceleration cell 6 is recessed, and the first half coupling cell 7 is coaxially recessed on the outer periphery of the rear surface. The first half acceleration cell 4 communicates with the second half coupling cell 5 through the slot 8, Numeral 6 communicates with the first-half combined cell 7 through a slot 9, and a beam axis hole 10 is formed in the center of each of the segments 1 and 2.

When high-frequency power is externally applied to such an ACS accelerating cavity, the high-frequency power resonates at a constant frequency due to the mechanical shape of each cell, and is formed from the front and rear portions by the resonating high-frequency power. An electric field for accelerating the charged particles is excited in the coupled cell 11 and the acceleration cell 12 formed from the former and latter parts, and the charged particles pass through the accelerating electric field of the beam hole 10 and are accelerated.

Here, the accelerating cell 12 and the binding cell 11 are designed to be evacuated to a vacuum so that charged particles do not collide with molecules such as air and disappear. Therefore, as shown in FIG. A vacuum pump is connected to the beam shaft hole 10 to evacuate. This has the advantage that the structure for exhausting is simple, but since the ACS type accelerating cavity has the structure shown in FIG. 3, the air conductance deteriorates and the ultimate vacuum level decreases. In addition, it takes a long time to exhaust to a predetermined degree of vacuum. Further, since the pump is connected to the beam hole, a discontinuous portion is generated in the beam hole, which has a problem that the acceleration performance is adversely affected.

Therefore, as shown in FIG. 5, a structure in which a vacuum exhaust passage is provided outside the acceleration cavity is also known, but in this structure,
Since the structure is such that the vacuum exhaust path is attached after the cavity is manufactured, the number of manufacturing steps, the number of parts, etc. increase, and there is a problem that the possibility of leakage also increases due to the increase in the number of vacuum ports. The substantial size of the cavity is so large that it is not easy to handle even during maintenance and assembly.

[Problems to be solved by the device]

That is, in the conventional vacuum exhaust structure, there are problems such as reduction in ultimate vacuum, increase in exhaust time, beam instability, number of manufacturing steps, number of parts, and vacuum reliability.

The present invention has been made in view of the above problems, and has a high-performance structure in which the acceleration cavity is quickly evacuated to a simple structure, is easy to manufacture and maintain, and does not cause a discontinuity in the beam axis.
An object is to provide a vacuum exhaust structure for an ACS type acceleration cavity.

[Means for solving the problem]

For this reason, the present invention has a front half segment in which a front half acceleration cell is recessed in the center of the rear surface and a rear half coupling cell is coaxially recessed in the outer periphery of the front surface, and a half acceleration cell in the center of the front surface. A plurality of segment pairs consisting of a pair of front and rear segments and a rear half segment in which the first half coupling cells are coaxially concavely formed in the outer periphery of the rear face and are coaxially and airtightly connected in series are assembled. In the ACS type accelerating cavity, a plurality of connecting cells of the segment pair of which the leading end is the rearmost end in the assembled state are provided so as to penetrate through the outer circumferences of the front half segment and the rear half segment at equal intervals. A plurality of exhaust holes forming a vertical exhaust passage in the axial direction, and connecting holes provided at the front end of the acceleration cavity and arranged at equal intervals are airtight in the front end openings of the vertical exhaust passages. Connected , Characterized in that comprising a vacuum manifold and the other end opening is connected to a vacuum pump.

[Action]

That is, according to the present invention, it is possible to realize an ACS type acceleration cavity that can be evacuated in a short time and is in a good vacuum state. Furthermore, by manufacturing the cavity main body and the vacuum exhaust passage integrally, manufacturing and maintenance are simplified, and by exhausting from the combined cavity, the beam can be stably accelerated without generating a discontinuous portion on the beam axis.

According to such a configuration, the plurality of vacuum exhaust passages are connected to the vacuum manifold, and the vacuum manifold exhausts the vacuum manifold to realize a vacuum in the acceleration cavity. By exhausting air directly from the combined cells in the circumferential direction, the air conductance is increased and the exhaust efficiency can be improved. Furthermore, since the pump is not attached to the beam shaft hole, the acceleration induced by the pump is increased. Performance degradation can be avoided.

〔Example〕

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a partial vertical cross-sectional view thereof, and FIG. 2 is a front view, a rear view and a rear view showing the accelerating cell side and the coupling cell side of one segment of FIG. FIG.

In the above drawing, the same reference numerals as those in FIG. 3 indicate the same members as those in the same drawing. A plurality of exhaust holes 13 having the same diameter are axially penetrated, and each exhaust hole 13 is communicated with the coupling cell 11, and the exhaust hole 13 of the frontmost segment pair is connected via the vacuum manifold 14. It is connected to the vacuum pump 15.

When assembling the ACS type acceleration cavity, each segment pair is coaxially and hermetically joined in the same phase, and the exhaust holes of each segment cooperate with each other to form a longitudinal exhaust passage in the axial direction. A front end opening of the vertical exhaust passage is connected to a vacuum pump via a vacuum manifold 14.

[Effect of device]

As described above, according to the present invention, the evacuation efficiency is improved by providing the evacuation hole in the coupling cell portion, and the acceleration cavity in a good vacuum state can be obtained. Further, since the acceleration cavity and the vacuum exhaust path can be manufactured integrally, the size of the cavity is also reduced, which leads to a reduction in manufacturing man-hours, the number of parts, etc., as compared with a structure in which the vacuum exhaust path is attached later.

In short, according to the present invention, a front half segment in which a front half acceleration cell is recessed in the center of the rear surface and a rear half coupling cell is coaxially recessed in the outer periphery of the front surface, and a half acceleration cell in the center of the front surface. And a rear half outer peripheral portion of which a front half coupling cell is coaxially recessed and a rear half segment, and a plurality of segment pairs consisting of a pair of front and rear segments are coaxially and airtightly connected in series for assembly. In the ACS-type accelerating cavity, the front half segment and the rear half segment are connected to each other in the vicinity of the outer periphery at equal intervals, and each segment is connected to each other and is connected to each other. A plurality of exhaust holes that form a longitudinal exhaust passage in the axial direction reaching the cells and connection holes that are attached to the front end of the acceleration cavity and are arranged at equal intervals are airtight at the front end openings of the respective vertical exhaust passages. Contact Since the other end opening is equipped with a vacuum manifold connected to a vacuum pump, the structure for quick vacuum evacuation of the accelerating cavity is simple and easy to manufacture and maintain, and the beam axis does not have discontinuity. The present invention is extremely useful industrially because it can obtain the vacuum exhaust structure of the ACS type acceleration cavity.

[Brief description of drawings]

FIG. 1 is an overall longitudinal sectional view showing an embodiment of the present invention, and FIG. 2 is a front view, a rear view and a sectional view of a segment constituting the ACS type acceleration cavity of FIG. FIG. 3 is a vertical sectional view showing a known ACS type acceleration cavity, and FIG.
FIG. 5 and FIG. 5 are vacuum exhaust structure diagrams of the ACS type acceleration cavity of FIG. 3, respectively. 1 …… First half segment, 2 …… Second half segment, 3
...... Segment pair, 4 ...... first half acceleration cell, 5 ...... second half combination cell, 6 ...... second half acceleration cell, 7 ...... first half combination cell, 8,9 ...... slot, 10 ...... beam axis hole , 11 …… coupling cell, 12 …… acceleration cell, 13 …… exhaust hole, 14 …… vacuum manifold, 15 …… vacuum pump,

Front page continuation (72) Creator Tatsuya Kageyama 2-chome, Namiki, Tsukuba, Ibaraki 303-302 (72) Yuichi Ryokan 522-105 (72), 5-chome, Matsushiro, Tsukuba, Ibaraki ▲ Kazuo Yoshino Ibaraki Tsukuba-shi Azuma 1-chome 402-102

Claims (1)

(57) [Scope of utility model registration request] 1. A front half segment in which a front half acceleration cell is recessed in the center of the rear surface and a rear half coupling cell is coaxially recessed in the outer periphery of the front surface, and a rear half acceleration cell is recessed in the center of the front surface. A plurality of segment pairs consisting of a pair of front and rear segments with a first half coupling cell coaxially recessed on the outer peripheral portion of the rear surface, which are provided, are assembled in series by coaxially and airtightly connecting in series. In the annular coupling cavity type acceleration cavity, a plurality of segment segments each having the same leading edge and the outermost portion of the first half segment are provided at equal intervals and communicate with each coupling cell. A plurality of exhaust holes that form a longitudinal exhaust passage in the axial direction reaching the combined cells, and connection holes provided at the front end of the acceleration cavity and arranged at equal intervals are respectively provided at the front end openings of the respective longitudinal exhaust passages. Airtight connection It is, in coupled cavity type accelerating cavity evacuation structure characterized in that comprising a vacuum manifold and the other end opening is connected to a vacuum pump.