JP2568001B2 - Support device for vacuum duct - Google Patents

Description

Detailed Description of the Invention

 [Object of the Invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synchrotron used for accelerating particles such as electrons and ions, and more particularly to a support device for a vacuum duct installed via a bending magnet.

[0002]

2. Description of the Related Art In a synchrotron which has relatively low incident energy and accelerates particles such as electrons and ions to high energy, when the deflection electromagnet is quickly started up and repeated, it is installed in the deflection electromagnet section. The eddy current generated in the vacuum duct becomes large. However, since a magnetic field is formed by this eddy current, a trajectory deviating from the originally intended trajectory of the bending electromagnet is formed. Further, since heat is generated by the eddy current, the vacuum duct may be heated and the amount of released gas may increase, resulting in a decrease in vacuum degree. Therefore, in order to reduce the effect of this eddy current as much as possible, it is necessary to make the thickness of the vacuum duct installed in the bending electromagnet as thin as possible. Conventionally, in terms of mechanical strength, The vacuum duct was a thin bellows type vacuum container.

On the other hand, the vacuum duct in the synchrotron generally requires a relatively high degree of vacuum in terms of beam life, so that it is often necessary to bake for heating degassing. By the way, the conventional thin duct bellows-shaped vacuum duct has a large axial expansion and contraction and a large axial displacement. Must be fixed so that it does not move to. Further, since the force acting on the vacuum duct is different between the case where the inside of the vacuum duct is at atmospheric pressure and the case where the inside of the vacuum duct is vacuum, it is necessary to prevent movement in the radius of curvature direction in any of these cases.

FIG. 5 shows a state in which a vacuum duct is installed in a bending electromagnet of a conventional synchrotron. In the figure,
Reference numeral 1 is a deflection electromagnet, and the vacuum duct 2 is installed on the beam orbit of the deflection electromagnet 1. Here, the vacuum duct 2 is
Since it is connected to the vacuum duct in the straight section via the flange, it is positioned by the flange, but in the case of a thin bellows type vacuum duct, the amount of expansion and contraction in the axial direction and the orthogonal displacement in the axial direction are large as described above. Therefore, even if the flange positions on both sides in the axial direction are fixed, the installation position of the intermediate portion in the axial direction is not determined. Therefore, as shown in the figure, a plurality of supporting members 3a and 3b are inserted between the yoke of the deflection electromagnet 1 and the vacuum duct 2 to restrain the movement in the radius of curvature direction.
In addition, 4a and 4b of the same figure show a coil.

[0005]

As shown in FIG. 5, the thin bellows-shaped vacuum duct 2 has a very large inner surface area as compared with a thick vacuum duct, and a large amount of gas is discharged from the vacuum duct. Cause a decrease in the degree of vacuum. Also, in the case of a synchrotron, it is required to raise the degree of vacuum in the vacuum duct 2 in order to increase the beam life as in the case of the storage ring, and it is necessary to degas the vacuum duct by heating it in order to obtain an ultra-vacuum. There is. Therefore, the supporting device of the vacuum duct 2 must be able to handle the thermal expansion during baking for heating degassing. However, in the conventional supporting device, since the vacuum duct 2 is designed under the condition that there is no displacement in the beam axis direction, a high load is locally applied to the supporting portion, and the thin-walled bellows-shaped vacuum duct 2 is The chances of breakage increase.

The thin bellows type vacuum duct 2 is
Since the amount of expansion and contraction and the displacement in the axial direction are large, when the vacuum duct is brought to atmospheric pressure during maintenance and inspection, it expands outward, and when vacuum is applied, it contracts inward, but with the conventional support device, the installation position of the vacuum duct is reproduced. Since it was not possible to secure the property, the installation position of the vacuum duct had to be adjusted each time.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to easily install a vacuum duct so as to have a desired curvature and to keep the vacuum duct at atmospheric pressure or vacuum. It is an object of the present invention to provide a vacuum duct supporting device which does not change the installation position in the radius of curvature direction in any case and allows thermal expansion and contraction of the vacuum duct when baking for heating degassing. [Constitution of Invention]

[0008]

SUMMARY OF THE INVENTION The present invention is a vacuum duct support device for supporting a vacuum duct having a curvature on a yoke portion of a deflection electromagnet, the vacuum duct having a thin bellows-like vacuum container, and a vacuum duct supporting device on the outer periphery of the vacuum duct. With fins,
A supporting unit including a supporting member whose length is adjustable and an insulating member having a low friction coefficient inserted between the supporting member and the vacuum duct is provided in a yoke portion in a direction orthogonal to the axial direction of the vacuum duct and in the vacuum duct. A plurality of them are arranged on both sides of the to support the vacuum duct.

[0009]

It is easy to install the device so as to have a desired curvature, and the installation position does not change because the radius of curvature is accurately constrained regardless of whether the pressure inside the vacuum duct is atmospheric pressure or vacuum. . Further, even if the vacuum duct thermally expands and contracts during heating and degassing baking, the support is slidable, so that excessive stress is not generated.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an embodiment of the present invention, and FIG. 2 is a plan view taken along the line AAAA of FIG.
In FIGS. 1 and 2, 10A and 10B represent support units, and the vacuum duct 11 is supported by the yoke portion of the deflection electromagnet 1 through a plurality of support units 10A and 10B so as to have a desired curvature. The support units 10A and 10B have the same structure but the mounting states are opposite. The vacuum duct 11 is formed of a thin stainless steel material in a bellows-shaped vacuum container, and the fins 11 are formed in a rectangular shape with an appropriate pitch on the outer circumference.
a is fixed.

FIG. 3 shows details of the structure of the support unit 10A. As shown in the figure, the support unit 10A includes a fixing metal fitting 12a, one end surface of which is in contact with the inner side surface of the coil 4b and a lower surface of which is in contact with the yoke portion of the deflection electromagnet 1, and the fixing metal fitting 12a.
Bolt 13a with one end screwed into
A mounting metal fitting 14a into which the other end of 13a is screwed, and a plurality of contact widths of the mounting metal fitting 14a and the fins 11a of the vacuum duct 11 are formed and are made of a material having a low friction coefficient such as GFRP or CFRP. It is composed of an insulating plate 15a. Here, the bolt 13a has an engaging portion 13 for a tool (spanner) in the middle.
c, right-hand thread 13d at one end, left-hand thread 13e at the other end
The fixing metal fitting 12a is provided with a screw hole 12c into which a right screw 13d is screwed, and the mounting metal fitting 14a is provided with a screw hole 14c into which a left screw 13e is screwed. 16a is a lock nut screwed into the right screw 13d, and 16b is a lock nut screwed into the left screw 13e.

Between the upper and lower surfaces of the fins 11a of the vacuum duct 11 and the magnetic poles of the deflection electromagnet 1, an insulating sheet 17a made of a material having a low friction coefficient similar to that of the insulating plate 15a described above,
17b is inserted.

On the other hand, the vacuum duct 11 is provided with a flange 11b at the end in the axial direction and is connected to the flange 18a of the vacuum duct 18 at the adjacent straight portion. This flange 11b is fixed to the deflection electromagnet 1 or a supporting device or floor. It is positioned and supported by a support installed on the level. FIG. 4 shows a supporting device 20 fixed to the bending electromagnet 1. That is, the supporting device 20
Are bolts 22 on the end plates 21a and 21b of the bending electromagnet 1, respectively.
Support frames 23a and 23b attached via a and 22b, and support frames 23a and 23b which are radially attached so as to face the center of the vacuum duct 11, and the tips are screwed into screw holes (not shown) of the flange 11b. Or bolts 24a, 24b that come into contact with the outer circumference of the flange 11b, and the bolts 24a,
It is composed of lock nuts 25a and 25b which are respectively screwed into 24b. Here, the support frame 23a is provided with a fixed portion 23c that comes into contact with the end plate 21a, and a support portion 23e that is located outside the fixed portion 23c and has an inclined surface and has a through hole (not shown) for the bolt 22a. . The support frame 23b is the support frame 23
It has the same structure as a and the mounting state is opposite.

Next, a method of supporting the vacuum duct 11 on the deflection electromagnet 1 (including positioning and bending in the radius of curvature direction) will be described. First, the axial positions of the bolts 22a and 22b of the supporting device 20 fixed to one end of the deflection electromagnet 1 are adjusted (for positioning the center of the vacuum duct 11), and the tip of the screw is provided on the outer periphery of the flange 11b. Screw in the hole and tighten the lock nuts 25a, 25b. Thereby, the deflection electromagnet 1
It is possible to position and support one end of the vacuum duct 11 in the axial direction with respect to. Next, the bolts 13a of the support units 10A and 10B are sequentially turned from the supported side to the other side in the axial direction.
13b is rotated to adjust the positions of the fittings 14a and 14b, and the lock nuts 16a and 16b are tightened. Thus, the bending electromagnet 1 can be bent and supported in the radius of curvature direction of the vacuum duct 11. Next, the axial positions of the bolts 22a and 22b of the supporting device 20 fixed to the other end of the bending electromagnet 1 are adjusted (for positioning the center of the vacuum duct 11).
Then, press the tip against the outer circumference of the flange 11b (do not screw it in) and tighten the lock nuts 25a and 25b. Thereby, the other end portion of the vacuum duct 11 in the axial direction with respect to the deflection electromagnet 1 can be positioned and supported. The mutual relationship between the magnetic pole center position of the deflection electromagnet 1 and the center position of the vacuum duct 11 can be checked by measuring the positional relationship between the fin 11a and the yoke of the deflection electromagnet 1 in the vacuum duct 11. The vertical direction of the vacuum duct 11 (direction shown in FIG. 1)
The height of the vacuum duct 11 is determined by the fins 11a of the vacuum duct 11 and a heat insulating material (not shown) provided on the portion of the vacuum duct 11 excluding the fins 11a, and the height direction is necessarily constrained.

Next, the operation of the embodiment configured as described above will be described. The vacuum duct 11 has a support device at one end.
It is fixed by 20, but since the other end is not fixed, it can be expanded and contracted in the axial direction, and an insulating plate having a low friction coefficient between the side surface of the fin 11a of the vacuum duct 11 and the support units 10A, 10B. 15a and 15b are inserted, and fin 11a
Insulation sheets 17a, 17 having a low friction coefficient between the upper and lower surfaces and the magnetic poles
Since b is inserted, baking for vacuum heating degassing (by energizing the vacuum duct 11)
When the vacuum duct 11 is stretched, the vacuum duct 11 easily slides even if it thermally expands, and an unreasonable force is not generated between them.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified. FIG. 5 shows another embodiment of the present invention, in which the vacuum duct 11 is supported on the yoke portion of the deflection electromagnet 1 by a plurality of support units 10A and 10B, which further facilitates bending in the radius of curvature direction. A plurality of bending adjustment units 30 for this purpose are provided. The bending adjustment unit 30 is composed of a fixing member 31 fixed to the side of the fin 11a having a small radius of curvature, and an adjusting bolt 32 having a turnbuckle structure attached between the adjacent fixing members 31 and 31. The method for supporting the vacuum duct 11 (including positioning and bending in the radius of curvature direction) in this embodiment is similar to the above-described embodiment in that one end of the vacuum duct 11 in the axial direction is positioned and supported by the supporting device 20. After that, a plurality of supporting units 10A and 10B are used to position and support the central portion and the end portion side in the axial direction, and the adjusting bolt of the bending adjusting unit 30 is performed.
By adjusting the length of 32, the inner surface of the vacuum duct 11 (the surface on the side with a small radius of curvature) is expanded and contracted to perform bending in the radius of curvature direction. The bending adjustment unit 30 is also adjusted sequentially from one end side. If the length of the adjusting bolt 32 is set in advance and the adjusting bolts are sequentially arranged and attached from one direction, bending can be easily performed in the radius of curvature direction. Next, the other end portion of the vacuum duct 11 in the axial direction is positioned and supported by the supporting device 20 as in the above-described embodiment. In this embodiment, the same effect as that of the above embodiment can be obtained.

[0017]

As described above, according to the present invention, an insulating plate having a low friction coefficient is attached to the outer periphery of a vacuum duct formed of a thin bellows type vacuum container by increasing fins to increase rigidity. Are contacted with each other, and the insulating plate is pressed by a supporting member having an adjustable length to be supported on the yoke portion of the deflection electromagnet, so that it is easy to form a desired curvature in the vacuum duct, and It is possible to provide a support device for a vacuum duct that does not generate excessive stress even with thermal expansion and contraction during vacuum heating degassing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view taken along the line AAAA of FIG.

FIG. 3 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 4 is a front view showing a supporting device at an end portion according to an embodiment of the present invention.

FIG. 5 is a plan view showing another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a conventional vacuum duct supporting device.

[Explanation of Codes] 1 ... Bending electromagnet, 4a, 4b ... Coil, 10A, 10B ... Support unit, 11 ... Vacuum duct, 11a ... Fin, 12a, 12
b ... fixing metal fittings, 13a, 13b ... bolts, 14a, 14b ... mounting metal fittings, 15a, 15b ... insulating plate, 17a, 17b ... insulating sheet,
20 ... Supporting device.

Claims (1)

(57) [Claims] 1. A vacuum duct supporting device for supporting a vacuum duct, which comprises a thin bellows-shaped vacuum container, with a curvature on a yoke portion of a deflecting electromagnet, wherein fins are provided on an outer periphery of the vacuum duct, and a length of the fin is provided. A supporting unit that is adjustable, and a supporting unit that includes an insulating member having a low friction coefficient inserted between the supporting member and the vacuum duct, and a supporting unit in the yoke portion in a direction orthogonal to the axial direction of the vacuum duct. A support device for a vacuum duct, wherein a plurality of vacuum ducts are arranged on both sides of the vacuum duct to support the vacuum duct.