JPS58103800A - Accelerating tube for particle accelerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an acceleration tube G of a particle accelerator that can be applied to an acceleration cavity of an accelerator.

(1) In the accelerating tube (high-frequency acceleration cavity) of a particle accelerator, an accelerating electrode and its attachment part (G) are required. First, the accelerating electrode is precisely positioned along the particle σ) acceleration line. For this positioning, high accuracy is required not only in the alignment of the electrodes themselves along the acceleration line, but also in the spacing between the electrodes and the inclination of each individual electrode. C, that is, the imperfect electrical contact is the acceleration performance, that is, the high frequency acceleration cavity σ
) The Q value C (energy stored in the acceleration cavity/energy lost in the additive cavity) decreases. In addition, in an accelerator tube that uses high power (Q) high frequency, local heat generation and discharge at the contact portion due to incomplete contact can cause problems.

Furthermore, since an ultra-high vacuum is required inside the high-frequency acceleration cavity,
The mounting section requires vacuum sealing. Regarding this vacuum seal G, the use of elastomer materials such as Piton is not allowed from the viewpoint of resistance to released gas and radiation.

Next, a schematic diagram of a conventional accelerating electrode attachment part is shown in FIG. In Figure 1, (1) is the fuselage, (2) is the accelerating electrode,
(3) is the stem, (4') is the mounting seat, (5) is the positioning ring, (6) is the positioning bush, (7) is the bellows mounting seat, (8) is the bellows, (9) is the contactor, (/ and (l/) are tilt adjustment bolts, (/2) and (1
3) is the nut for fixing the tilt adjustment bolt, (ilI) is the push pole for height adjustment), (15) is the positioning bush fixing pole), (/A) is the spring washer for the positioning bush fixing bolt.
(/7) is the number mounting bolt), (7g) is the contactor mounting bolt, (19) is the mounting seat fixing port), C:lO)
is the positioning ring position adjustment bolt, (,2/) is the nut for fixing the positioning ring position adjustment bolt), (:t2)~
(C5 is a gasket for vacuum sealing. In Figure 1, accelerating cavity body (1) and accelerating electrode (2) σ) To explain the installation procedure, bellows (g) and bellows mounting seat (7) is pre-welded at 8 parts.
The bellows (Ii') and the stem (3) are welded in advance at part b G. Therefore, the acceleration it pole (J), stem (3), bellows (&) and bellows mounting seat (7
) are one and the same. Next, the contactor (9) divided into λ parts (not shown) is attached to the stem (3) by using contactor mounting bolts (/K) as shown in the figure.

Next, insert the accelerating electrode (, 2) from below the body (1), place the vacuum seal (2q) and (sword) between them, and install the bellows mounting seat (7) and mounting seat (<z). Seat fixing bolt (/
9). Next, insert the vacuum seal (〃) and (3) between them, and attach the mounting seat (ri) to the body (1) with the mounting seat mounting bolt (/7). In addition, after installing the positioning ring (jt) on the mounting seat (4'), attach the tilt adjustment pole to the positioning bush (B) in advance.
/l) and the nuts (/2) and (/3) for fixing the inclination adjustment bolt are temporarily assembled above the stem (3), and the positioning bush (B) is attached to the positioning ring (2).
3) Assemble so that G fits in.

After completing the temporary assembly in this way, the positioning ring position adjustment bolts (2) are installed at positions divided into equal parts on the outer periphery of the mounting seat (4'). (omitted)), push the outer periphery of the positioning ring (S) to adjust the horizontal position of the accelerating electrode (C), and after the adjustment is completed, fix it with the fixing nut C2/).

Next, use the height adjustment push bolt (/+) to adjust the height of the positioning bush (adjust the height of the height). c'
& Since only a small amount has been inserted in advance, the accelerating electrode (
2) is moved upward and its position in the height direction is adjusted. Due to this height adjustment, the contactor (9) comes into contact with the inner surface of the body (1), but this contactor (
9) is in the shape of a disc spring as shown, and comes into contact with a certain contact pressure.

After completing the adjustment of the accelerating electrode (, 2) in this way, fix the fixing pole (/S) and the fixing bolt spring washer (/A).
Fix it by. At the same time, the direction around the stem axis of the accelerating electrode σ) (direction e in FIG. 7) is also adjusted using the long d (not shown) provided on the positioning bush (A).

Finally, the inclination of the accelerating electrode (2) is adjusted using the inclination adjustment bolt (/) and (l/), and after adjustment, the identification nut (/) is adjusted.
2) and (/3). It should be noted that this tilt adjustment causes fluctuations in the horizontal and height directions of the accelerating electrode (C), but the amount of fluctuation is small and poses no problem in use. If there is a problem in use, the horizontal and height directions can be adjusted again.

However, the conventional device has the following drawbacks. In other words, the high frequency contact between the body and the stem (3) is
Since this is done using a countersunk-shaped contactor (9), the rigidity of the contactor (9) is limited and the contact pressure is insufficient.
There was a possibility of local heat generation due to insufficient contact pressure. Furthermore, since some of the high frequency waves flow through the bellows (g), the bellows is heated by the high frequency waves and burnt out, posing the risk of vacuum leakage.

Furthermore, since there are a large number of position adjustment bolts for the acceleration north pole (co), there is a problem that it takes a lot of time to accurately position the pole.

The present invention was proposed in order to overcome the above-mentioned conventional drawbacks, but by pulling up the stem, the electrode and the tapered portion provided in the acceleration cavity are pressed against each other, thereby simultaneously obtaining complete high-frequency contact. We would like to provide an acceleration tube for a particle accelerator in which the positioning in the height direction is completed and the rigidity of the stem is small, so fine adjustments in other directions can be easily made with appropriate tools. .

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a side sectional view showing the entire acceleration cavity showing an embodiment of the present invention, FIG. 3 is a sectional view taken from A to A in FIG. 2, and FIG. The figure is B in Figure 2.
FIG.

In Figures 2 to 11, (3/) is the body of the accelerating cavity, (32) is the accelerating electrode, (33) is the stem, (3 da)
is a taber ring, (3!;) is a diaphragm for vacuum sealing, (3!) is a preset nut, (37) is a thrust bearing, (3g) is a thrust receiver washer, (39) is an adjustment bolt, (tlO) is a lock nut To explain the zero-order action, 7 from inside the body (3/) of the accelerating cavity.
The stem (33) integrated with the Jn speed electrode (32) is attached to the body (3).
/) σ) Insert into the tapered part (3/a). At this time, a taber ring (3) made of a conductive soft metal (for example, annealed copper or aluminum) is inserted into the tapered portion (, ?, ?a) of the stem in advance.

After that, the inner circumference of the vacuum sealing diaphragm (3S) (3!
;a) and the outer periphery (3!;b) respectively with the stem (33!
) end (33b), ) hook body (3/) end (31b)
Weld to. Then, attach the thrust bearing (37) and thrust bearing washer (3g) to the four parts (J/c) of the fuselage (3/).
). Next, lightly screw the adjustment bolt (39) and lock nut (4to) into the preset nut (36) installed in advance from above the stem (33).

After holding the accelerating electrodes (32) from inside the body of the accelerating cavity with a jig (not shown), screw in the preset nut (3A) with the specified torque.The accelerating electrodes (3) will be controlled by the jig and tool. With σ being restricted, one stem (33) does not rotate but moves upward. Natsu for preset) (3
When the convex part (J4a) of A) hits the thrust receiver washer (3g) and is further tightened to the specified torque, the dimensions of the related parts are designed to fall within the allowable alignment range G, so the acceleration electrode ( 3λ) is automatically determined.Next, in order to accurately position the accelerating electrodes (3, 2), use a jig (not shown) to gradually move the stem (33). By further rotating the adjusting bolt (39), adjust the inclination of the accelerating electrode so that the accelerating electrode falls within the predetermined alignment, and then tighten the lock nut (39).
170) This permanent constant is small because it is a fine adjustment work, and does not have a large effect on the resonance conditions of the accelerating cavity body. In addition, the diaphragm (3!;)
is provided to absorb displacement in the axial direction between the stem (33) and the body (3/). Finally, preset Nando (
3) Attach a rotation stopper (not shown) to prevent rotation.

5 to 7 show embodiments of the present invention from λ to 5. First, FIG. Although vacuum sealing is performed by a ring, there is no difference in operation and effect l/X0 (9) Next body (3/) and taber ring (3q)
1 is made straight to make it easier to work with, and a conductive soft metal (tI2) is sandwiched and tightened between the stem (33) and the body (3/) of the acceleration cavity to obtain perfect high-frequency contact. However, there is no difference in effectiveness.

The present invention is constructed as described above in detail, and reliable high-frequency contact can be obtained by the wedge action of the conductive tapered ring pressed into the tapered portion of the stem and body. Furthermore, by reducing the stiffness of the stem (σ), it is possible to slightly deform the accelerating electrode using jigs and tools. Therefore, deformation of the stem attachment portion can be restrained, and the position and inclination can be easily adjusted.

[Brief explanation of drawings]

FIG. 1 is a W cross-sectional view of a conventional accelerating electrode attachment part, FIG. 2 is a side cross-sectional view showing an acceleration cavity showing an embodiment of the present invention, and FIG. Figure 9 is a detailed view of part B in Figure λ σ), Figure S, Figure 6, and Figure 7 are cross-sectional views showing the embodiment of the present invention, which corresponds to Figure 0. Explanation 3/...Acceleration cavity body 3λ...Acceleration electrode 33.
・Stem 3 da...Taber ring 3S・
...Diaphragm 3/a for vacuum sealing...Taber portion 33a of the fuselage...Taber portion of the stem Patent applicant Mitsubishi Heavy Industries, Ltd. (/l)

Claims (1)

[Claims] A hollow tube having a radially extending taper hole drilled through the wall, the interior of which is maintained in a high vacuum state, a hollow stem extending inwardly and outwardly through the tapered hole, and an accelerator fixed to the inner end of the stem. an electrode, a boss formed protruding from the outer surface of the stem and forming an annular space between it and the tapered surface of the tapered hole, and a boss fitted between the inner circumferential surface of the outer end of the tapered hole and the outer surface of the stem. A flexible annular seal member, a position adjustment member screwed onto the outer surface of the outer end of the stem and in contact with the outer surface of the hollow tube, and a contact conductive ring sandwiched between the tapered surface and the outer surface of the boss. An acceleration tube for a particle accelerator, characterized in that the ring is made of soft metal.