JPH07192898A - Superconductive electromagnet device for charged particle and electron storing ring - Google Patents

Abstract

PURPOSE:To always maintain the degree of vacuum high at a part of a device, through which an electron beam passes, and stabilize the degree of vacuum by providing a joint, which is provided with a vacuum vessel, in a beam chamber, and forming an opening part in the vacuum chamber to separate the vacuum vessel and a vacuum space inside of the beam chamber. CONSTITUTION:A vacuum vessel 5 is vacuum-exhausted to a predetermined degree of vacuum to obtain the degree of vacuum required for heat insulation of a low- temperature part. Liquid helium is supplied to a superconductive coil 1 from a liquid helium reservoir 34 through helium pipelines A35, B36, and cooled to a predetermined temperature, and the coil 1 is excited by an external exciting power source to generate a predetermined magnetic field. Charged particles pass through a beam chamber 26, and a flange joint provided with a vacuum seal is provided in the vacuum vessel 5 as a part, in which the chamber 26 passes through the vacuum vessel 5, and opening is formed. A vacuum space of the vacuum vessel 5 and a vacuum space inside of the beam chamber 26 are thereby separated from each other, and even in the case where the degree of vacuum of the vacuum vessel 5 is deteriorated, vacuum of the chamber 26 is maintained at a predetermined degree of vacuum without receiving the influence to obtain the stabilized electron beam for a long time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting electromagnet for charged particles which is applied to a portion where a magnetic field is generated by using a superconducting coil to regulate and guide charged particles to a desired orbit.

[0002]

2. Description of the Related Art FIG. 24 shows, for example, Microselectr.
onic Engineering 11 (1990) 2
An example of the conventional superconducting electromagnet for charged particles shown on pages 25-228, that is, a bird's-eye view of a superconducting bending electromagnet for an electron storage ring, FIG. 25 is a vertical cross-sectional view of the central portion of FIG. 24, and FIG. FIG. 27 is a perspective view showing the shape of the coil. In the figure, 1 is a pair of superconducting coils in which a superconducting wire is wound in a banana shape and both ends thereof are flipped up, and 2 is a pair of the above-mentioned superconducting coils 1 which are housed so as to be substantially symmetrical vertically with a certain interval. The coil container 3 is a vacuum container having a rectangular cross section formed in the central portion of the coil container 2 so that the outer side is opened along the deflection (bending) radius of the banana-shaped coil on the vertically symmetrical surface of the superconducting coil 1. An electron beam passage, 4 is a heat shield that covers the circumference of the coil container 2 and shields radiant heat, 5 is a vacuum chamber that houses the above-described components, 6 is a heat insulating support member that adiabatically supports the coil container 2 in the vacuum chamber, 7 Is a helium supply port for supplying liquid helium to the coil container 2, and 8 is the vacuum chamber 5
Beam entrance port for guiding the electron beam to the electron beam passage 3 through the wall surface on the linear orbit side of the electron beam passage 3
A beam outlet port for taking out an electron beam from the vacuum chamber 5 through the vacuum chamber 5 and a plurality of radiant light ports 10 arranged at appropriate intervals through the vacuum chamber 5 in the tangential direction of the trajectory of the electron beam passage 3. Is a superconducting electromagnet. FIG. 28 shows the superconducting electromagnet 1 constructed as described above.
1 is an example in which 1 is applied to an electron storage ring, and in the figure, two superconducting electromagnets 11 are symmetrically installed at a fixed distance so as to form a racetrack type beam orbit, and 12 is a linear accelerator. Beam injector for guiding electrons accelerated to a predetermined energy to a circular orbit by a synchrotron (not shown) or the like, 13 is a high-frequency cavity, and 14 is a linear section beam duct that connects the superconducting electromagnet and each component of the linear section. Is. The ends of the plurality of emission light ports 10 are connected to each other via extension beam ducts or the like so that the vacuum can be sealed midway or at the ends.
(Not shown).

Next, the operation will be described. First, the vacuum chamber 5 of the superconducting electromagnet 11 is evacuated to a predetermined vacuum level using a vacuum pump (not shown). Next, liquid helium is supplied to the coil container 2 from the helium supply port 7 to cool the superconducting coil 1 to a predetermined temperature. When the superconducting coil 1 is in the superconducting state (state in which the electric resistance is 0), the desired magnetic field can be generated by energizing it through an external excitation power source (not shown). The operation when the superconducting electromagnet 11 is applied to the electron storage ring shown in FIG. 28 is as follows. The electrons accelerated to a predetermined energy by the linear accelerator or the synchrotron are incident on the circular orbit of the ring from the beam injector 12. The high-energy electron beam travels from the straight beam duct 14 through the beam entrance port 8, the electron beam passage 3 and the beam exit port 9 on the racetrack orbit. When a certain amount of this electron is accumulated, the injection is stopped, and thereafter, the resonator such as the high frequency cavity continues to work to supplement the lost energy and continue the operation for a long time. Here, the electrons emit bremsstrahlung, that is, synchrotron radiation, in the tangential direction of the orbit when bent to 180 degrees in the deflection magnetic field of the superconducting electromagnet. This synchrotron radiation light is extracted from a plurality of radiation light ports 10 and is widely used for various measurements at the atomic and molecular level such as X-ray lithography and X-ray diffraction. Here, if there are residual gas molecules on the orbit around which the electron beam (a bundle of accumulated electrons accelerated to high energy), the accelerated electrons collide with the residual gas molecules and the energy is attenuated or scattered. It will disappear by jumping out of the orbit, and the accumulated life will be shortened. Therefore, in consideration of the accumulated life of the electron beam, the inside of the electron beam passage 3 is usually set to an ultrahigh vacuum of the order of 10 ⁻⁹ Torr. on the other hand,
The superconducting coil 1 cooled by liquid helium is heat-insulated by vacuum, but the degree of vacuum required to ensure heat-insulating performance is 10 when heat transfer due to molecular conduction of residual gas is taken into consideration.
^-6 Torr order is sufficient. The superconducting electromagnet 11 has a structure in which the electron beam passage 3 for passing an electron beam and the vacuum of the adiabatic vacuum portion of the superconducting coil, that is, the vacuum chamber 5 communicate with each other.

[0004]

Since the conventional superconducting electromagnet for an electron storage ring has a structure in which the adiabatic vacuum portion and the vacuum of the electron beam passage communicate with each other as described above, the wall surface forming the adiabatic space portion, especially the superconducting portion. The cooling surface including the coil maintains the adsorption equilibrium state of the residual gas molecules by the action of the cryopump, and when thermal disturbance is applied to this, the equilibrium state is broken and a part of the adsorbed gas is desorbed, and the vacuum chamber The degree of vacuum in No. 5 may deteriorate, and along with this, the electron beam passage 3
The ultra-high vacuum inside cannot be maintained, and the electron beam storage life may be significantly reduced. Also, if the vacuum breaks at any of the beam lines connected to the outside from the electron beam inlet port, the outlet port and the synchrotron radiation port during operation, it will directly affect the vacuum chamber of the superconducting electromagnet and maintain the heat insulation. When it disappeared, there were drawbacks such as abnormal evaporation of liquid helium, quenching of the superconducting coil (transition from superconducting state to normal conducting state), and failure of functioning as a superconducting electromagnet.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and the vacuum of the portion through which the electron beam passes is always maintained at an ultrahigh vacuum to stably guide the beam, and the beam connected to the outside of the superconducting electromagnet is also provided. An object of the present invention is to provide a superconducting electromagnet having a structure in which the vacuum break on the line side does not affect the adiabatic vacuum. Further, in the present invention,
Providing a cryostat that reduces the heat entering the low temperature part of the superconducting coil and reduces the evaporation of liquid helium, and even if the magnetic field suddenly changes due to quenching of the superconducting coil, eddy currents are induced in the components such as the heat shield. It is an object of the present invention to provide a superconducting electromagnet which has a structure that is hard to be subjected to heat and which does not cause a temperature rise of the heat shield member itself or deformation due to electromagnetic force.

[0006]

According to a first aspect of the present invention, a beam chamber for forming an independent vacuum space is installed in a portion of a superconducting electromagnet through which an electron beam passes, and a vacuum seal is provided at a beam inlet and outlet port portion penetrating a vacuum chamber. The charged particle beam was guided by opening through the flange joint provided with.

According to a second aspect of the present invention, a plurality of radiant light ports are provided on the outer peripheral wall of the beam chamber so that the radiant light ports are opened through a flange joint provided with a vacuum seal at a portion penetrating the vacuum chamber. The synchrotron radiation can be taken out.

According to a third aspect of the present invention, the beam chamber is adiabatically supported on the superconducting coil unit via a plurality of heat insulating support members, and a plurality of ducts communicating with the beam chamber are provided in a portion penetrating the vacuum chamber. A flexible joint that can be expanded and contracted is provided.

According to a fourth aspect of the invention, when the beam chamber is supported on the superconducting coil by a plurality of heat insulating support members, one or two reference positions are substantially fixedly supported, and the beam chamber is heated or superconducting. Displacement caused by thermal expansion and contraction caused by cooling of the coil is absorbed by sliding and bending displacement of the heat insulating support member so that the relative position of the beam chamber and the superconducting coil can be maintained in substantially the same state.

In a fifth aspect of the present invention, a plurality of support fittings are provided on the side surface of the beam chamber, and a heat insulating support member is attached to the support fitting so as to be supported on the superconducting coil.

According to a sixth aspect of the invention, the beam chamber is supported by a plurality of multiple cylindrical heat insulating columns.

According to the invention of claim 7, a radiant heat shielding material covering substantially the entire circumference of the beam chamber is integrally attached and incorporated into the superconducting coil.

According to an eighth aspect of the present invention, a multilayer laminated heat insulating material is directly wound around the beam chamber as a heat insulating material of the beam chamber, and a heat shield covering the whole is integrally installed around the beam chamber by a plurality of heat insulating supporting rods. I did it.

According to a ninth aspect of the present invention, a member of a beam chamber, a heat shield, and a heat insulating support rod for supporting between the heat shield and a flexible fiber laminated resin laminated plate, a laminated rod,
It was made into a laminated pipe or the like.

According to a tenth aspect of the present invention, among the heat shield members of the beam chamber, a member that covers a surface of the heat shield member in a direction substantially parallel to the magnetic flux of the main magnetic field generated by the superconducting coil is a non-magnetic metal plate having a large thermal conductivity and a magnetic flux. The members that cover the surfaces in the intersecting direction are made of non-magnetic metal plates having high electric resistance.

According to the invention of claim 11, the heat shield is made of a thin metal plate having a non-magnetic property and a large electric resistance, and a heat transfer plate made of a metal having a non-magnetic property and a high thermal conductivity is arranged at an appropriate interval and is bonded with an adhesive. The shield plate is integrated.

According to the twelfth aspect of the invention, when a plurality of beam ducts are taken out from the beam chamber through each port of the vacuum chamber, a relay flange is provided at each port and the beam duct communicates with the beam chamber through the relay flange. The vacuum in the vacuum chamber and the vacuum in the vacuum chamber were individually sealed.

According to the thirteenth aspect of the present invention, a cooling jacket or a cooling pipe is provided on the wall surface of the beam chamber to circulate and cool the refrigerant of the general-purpose refrigerator or the low temperature liquefied gas.

[0019]

In the superconducting electromagnet constructed according to the invention of claim 1, since the beam chamber for passing the electron beam is independently installed in the vacuum chamber, the superconducting coil section is subject to thermal disturbance or the like and the vacuum chamber is affected. Even if the degree of vacuum inside deteriorates, the inside of the beam chamber is not affected and the electron beam can be guided while maintaining an ultrahigh vacuum. On the contrary, since the adiabatic vacuum of the superconducting coil is not affected even if the vacuum on the beam chamber side is deteriorated, the cryostat can be stably operated without causing abnormal evaporation of liquid helium.

According to the second aspect of the present invention, since a plurality of beam ducts are provided in the tangential direction of the beam orbit from the beam chamber and vacuum seals are provided respectively at the portions penetrating the ports of the vacuum chamber, the degree of vacuum on the vacuum chamber side is reduced. The desired beam can be taken out by keeping the inside of the beam chamber in an ultra-high vacuum state without being affected by the change.

According to the third aspect of the present invention, the beam chamber is installed so as to slide on the superconducting coil unit via the heat insulating support member, and a flexible joint is provided from the beam chamber to a portion where a plurality of beam ducts penetrate the vacuum chamber. Since the beam chamber and the superconducting coil unit are not misaligned and no stress is generated due to the thermal expansion or contraction of the components, the beam chamber and the superconducting coil unit are kept at a constant distance. Can be installed.

According to the fourth aspect of the present invention, the beam chamber is fixedly heat-insulated and supported at one or two places on the superconducting coil unit, and a plurality of other heat-insulating support members are abutted or supported with a slight gap. Therefore, the stress caused by the positional deviation of the supporting portion and the difference in thermal expansion can be released, and the relative reference positions of the beam chamber and the superconducting coil unit can be kept substantially constant.

According to the invention of claim 5, a plurality of support fittings are provided on the side surface of the beam chamber, and the heat insulating support member is attached through the support fittings. Therefore, the installation span of the heat insulating support member up to the support surface of the superconducting coil unit is improved. Can be taken for a long time. In addition, the work space for mounting the heat insulating support member is expanded.

In the invention of claim 6, since the beam chamber is installed on the superconducting coil through a plurality of multiple cylindrical heat insulating columns, a predetermined heat insulating distance can be secured even in a narrow installation space, and the heat insulating support member itself penetrates by heat conduction. The heat can be made small enough.

According to the seventh aspect of the invention, since the radiant heat shielding member integrated with the beam chamber in advance is combined with the superconducting coil unit through the heat insulating support member, the construction can be carried out reliably and easily.

In the invention of claim 8, the multilayer laminated heat insulating material is wound around the beam chamber, and the heat shield integrated with the heat insulating support rod is integrated with the superconducting coil unit so as to substantially cover the circumference. You can always visually check the assembly status. Further, since the outer dimensions are sequentially measured and the fine adjustment of the assembling can be surely performed, mutual thermal contact can be prevented.

According to the ninth aspect of the invention, the beam chamber, the heat shield, and the plurality of heat insulating support rods for supporting the heat shields are made flexible by using fiber-reinforced resin laminated rods, laminated pipes, or the like. Slight dimensional error of
Elongation difference due to thermal expansion and contraction can be absorbed by elastic deformation. Further, by elastically deforming the heat insulating support rod, the rise in stress of the heat shield itself can be alleviated, so that contact due to deformation of the heat shield can be prevented.

In the tenth aspect of the present invention, the shield member having a surface parallel to the magnetic field formed by the superconducting coil is a non-magnetic metal plate having a small thermal resistance, and the member having a surface intersecting with the magnetic field is made of a non-magnetic metal having a large electric resistance. Since it is a thin plate, even if there is a sharp change in the magnetic field due to quenching of the superconducting coil, the eddy current induced in the heat shield is small and the deformation of the heat shield itself due to the electromagnetic force can be suppressed. Further, the shield member on the surface intersecting with the magnetic flux can cool the heat shield by using a member having a small thermal resistance as a heat transfer path.

In the invention of claim 11, as a heat shield member, a thin plate of a non-magnetic metal having a large electric resistance is bonded to a heat transfer plate made of a non-magnetic metal having a small heat resistance with an adhesive agent. Even if there is a sudden change in the magnetic field due to, for example, the eddy current flowing through the member in the heat shield can be reduced, and the electromagnetic force acting on the shield plate itself can be reduced to suppress deformation. Further, the shield plate can be cooled by heat conduction by connecting the end of the heat transfer plate to a cold heat source.

In the twelfth aspect of the invention, when the beam chamber is integrated with the superconducting coil unit and mounted in the vacuum chamber, the joint flange of the beam chamber and the through port of the vacuum chamber are connected via the relay flange. A material having a small gas release rate can be applied to this portion, and it is possible to easily reach an ultra-high vacuum in a portion communicating with the beam chamber. Further, when the beam chamber is attached to the vacuum chamber of the superconducting electromagnet, the relay flange can be removed so that the working space is widened and the assembling can be facilitated.

According to the thirteenth aspect of the present invention, since the wall of the beam chamber can be cooled, the heat entering the superconducting coil unit due to the radiant heat and the heat conduction through the heat insulating support member is suppressed, and the liquid helium as the cryogen for the superconducting coil is evaporated. The loss can be reduced.

[0032]

【Example】

Example 1. 1 is a vertical sectional view of a central portion of a superconducting electromagnet for charged particles showing an embodiment of the invention of claims 1 and 2, and FIG. 2 is a horizontal sectional view of FIG. In the figure 1,
4, 5, 6, 7, and 10 are the same or corresponding parts as the conventional device. The coordinate axes for explanation are also shown in each figure.
20 is an upper coil container for housing the superconducting coil 1, 21
Is a lower coil container that houses the superconducting coil 1 symmetrically with the above 20, and 22 is an upper coil container 20 and a lower coil container 2.
1 is a low temperature electromagnetic force supporter mounted to secure a space for taking out an orbit of electrons and a synchrotron radiation, and supports an electromagnetic force acting between upper and lower superconducting coils 1. Reference numeral 23 is a superconducting coil unit in which the above 20, 21 and 22 are integrated, 24 is a Z-axis heat insulating support member that supports the vertical load of the superconducting coil unit 23, and 25 is a unbalanced electromagnetic force in the horizontal direction of the water level. X-axis heat insulating support material, 26 is a beam chamber provided with an orbit of electrons inserted into the upper coil container 20, the lower coil container 21, and the low temperature heat insulating support member 22 with a proper interval respectively, and 27 is a beam chamber. A flange joint provided with vacuum seals at both ends of 26 and connected to the beam inlet port 8 and the beam outlet port 9 of the vacuum chamber 5, respectively.
Is a plurality of synchrotron radiation ports 1 of the vacuum chamber 5 for extracting synchrotron radiation from the outer peripheral wall of the beam chamber 26.
0 is a plurality of radiant light ducts A provided so as to communicate with each other via a vacuum seal.

Reference numeral 31 denotes a magnetic shield provided outside the vacuum chamber 5 so as to surround almost the entire circumference thereof in order to reduce the leakage magnetic field to the outside of the superconducting coil, and 32 penetrates the magnetic shield 31 from the outer wall surface of the vacuum chamber 5. The radiation light ducts B and 33 for guiding the synchrotron radiation light are vacuum gate valves provided so as to be able to block the open end of the radiation light duct B. Reference numeral 34 is a liquid helium reservoir provided above the magnetic shield 31, 35 is a helium distillation vacuum chamber for vacuum heat insulation around the liquid helium reservoir provided in communication with the vacuum chamber 5 and a vacuum portion, and 36 is a liquid helium reservoir 34 and an upper portion. Helium pipes A and 37 that connect the coil container 20 to each other are helium pipes B that similarly connect the liquid helium reservoir 34 and the lower coil container 21.

Next, the operation will be described. The vacuum chamber 5 is evacuated to a predetermined degree of vacuum using a vacuum pump (not shown) as in the conventional apparatus. In this case, the degree of vacuum of 10 ⁻⁶ Torr order required for heat insulation of the low temperature part may be obtained. When the vacuum degree reaches a predetermined level, the superconducting coil 1 moves from the liquid helium reservoir 34 to the helium pipe A35 and the helium pipe B.
Liquid helium is supplied from 36 to cool it to a predetermined temperature,
An external excitation power source (not shown) is connected to excite the superconducting coil 1 to generate a desired magnetic field.

When this superconducting electromagnet 11 is applied to the electron storage ring as in the conventional apparatus, the beam chamber 26 integrated and incorporated in the superconducting coil unit 23 has the beam injector 12 and the high frequency cavity through the linear beam duct 14. 13 and the like are connected to each other to form one round of the ring as an independent vacuum donut. This vacuum donut part is ^10-10 To using an ultra high vacuum pump (not shown).
Evacuate to obtain a vacuum degree of rr order.
In this state, the high-energy accelerated electron beam incident from the beam injector 12 circulates from the linear beam duct 14 through the beam inlet port 8, the beam chamber 26, and the beam outlet port 9 of the superconducting electromagnet. Here, since the ultra-high vacuum portion of the beam chamber 26 is provided independently of the heat insulating vacuum of the vacuum chamber 5 of the superconducting electromagnet 11, even if the vacuum degree of the vacuum chamber 5 deteriorates due to thermal disturbance on the superconducting coil side, The vacuum inside the chamber 26 is not affected and the electron beam can be stably circulated for a long time by maintaining a predetermined degree of vacuum. Further, since it is not necessary to make the entire vacuum chamber 5 to have an ultrahigh vacuum, there is an advantage that the volume of the ultrahigh vacuum portion can be greatly reduced and the vacuum exhaust becomes easy.

On the contrary, even if the beam chamber 26 is opened to the atmosphere, the degree of vacuum of the vacuum chamber 5 is not affected, so that the superconducting electromagnet 11 can be operated regardless of the vacuum of the beam chamber 26. .

Further, a radiant light duct A2 for taking out radiant light
Since 8 is directly connected to the radiant light port 10 of the vacuum chamber 5 from the side wall surface of the beam chamber 26 to form a vacuum common to the beam chamber 26, the radiant light can be efficiently led out. Also, the synchrotron radiation duct B3
Even if the air flows in from the 2 side, the degree of vacuum in the vacuum chamber 5 on the superconducting coil 1 side is not affected in the same manner as described above, so that the superconducting electromagnet 11 can be operated stably.

Example 2. 3 is a plan view showing an embodiment of claim 3, and FIG. 4 is a sectional view of a portion (A-A) of FIG. In the first embodiment, the flange joints 27 and the plural radiant light ducts A28 at both ends of the beam chamber 26 are directly connected to the beam inlet port 8, the beam outlet port 9 and the plural radiant light ports 10 of the vacuum chamber 5, respectively. In the present embodiment, 41 is an expandable and retractable first bellows joint provided at both ends of the beam chamber, and 42 are provided at portions of a plurality of radiation light ducts connected to the radiation light port 10 on the vacuum chamber 5 side. An expandable second bellows joint 43 is a first heat insulating support member provided so as to support the beam chamber 26 on the superconducting coil 1 in a heat insulating manner. The heat insulating support member 43 is made of a heat insulating material, is fixed to the beam chamber 26, and has a coil container 20.
21 is slidably abutted or inserted with a slight gap. The first heat insulating support member 43 may be provided with one or more fulcrums, depending on the shape, size, weight, etc. of the beam chamber. With such a configuration, the vertical gap between the superconducting coil unit 23 and the beam chamber 26 can be kept substantially constant, and thermal contact can be prevented. Further, since the beam chamber 26 and the vacuum chamber 5 are connected via the flexible bellows joints 41 and 42, even if the beam chamber 26 and the superconducting coil unit 23 are misaligned due to dimensional error or thermal expansion, the bellows portion is not formed. This displacement can be tolerated and excessive stress is not applied to the first heat insulating support member 43. Although the heat insulating support member 43 is fixed to the beam chamber 26 in this embodiment, it may be fixed to the coil containers 20 and 21 and slidably brought into contact with the beam chamber 26.

Example 3. FIG. 5 is a partial sectional view showing an embodiment of the invention of claim 4. In the second embodiment, the first heat insulating support member 43 is arranged so that the distance between the superconducting coil unit 23 and the beam chamber 26 can be kept substantially constant. However, 44 of this embodiment is a part of the heat insulating member 43. The second heat insulating support member is a second heat insulating support member which is heat-insulated and supported on the lower coil container 21 by limiting the sliding distance in the horizontal plane. As the second heat insulating support member 44, one of the first heat insulating support members 43 near the central axis of symmetry is selected.
Similar to that shown in FIG. 3, the other plural points are fixedly coupled to the beam chamber 26 side by using the first heat insulating support member 43 and abut on the superconducting coil unit 23 side or slide with a slight gap. Support as much as possible. With such a configuration, the positional deviation amount between the superconducting coil unit 23 and the beam chamber 26 is limited, so that the interval can be maintained substantially constant and the relative position of the superconducting coil unit 23 and the beam chamber 26 in the horizontal plane can be maintained. The electron beam can be held at a substantially standard position and the electron beam can be stably circulated. In addition, the superconducting coil side of the second heat insulating support member can be slid within a limited range in preparation for each displacement due to thermal contraction of the superconducting coil unit 23 during cooling and thermal expansion of the beam chamber 26 during baking. Therefore, it is possible to suppress an increase in internal stress of each component. The second heat insulating support member 44 of the present embodiment is the beam chamber 2
It was fixed to 6, but to the coil containers 20 and 21 in reverse,
The beam chamber 26 may be slidable with a limitation.

Example 4. FIG. 6 is a plan view showing another embodiment of the invention of claim 4, and FIG. 7 is a sectional view of a portion (A-A) of FIG. In the third embodiment, the beam chamber 26 is supported via the second heat insulating support member 44 so as to be fixed in position on the lower coil container 21, but in the figure, 45 indicates the second heat insulating support member 44. The beam chamber 26 is provided on a substantially symmetrical X-axis on the plan view,
This is a third heat insulating support member which allows displacement of ± several millimeters in a direction parallel to the X axis and restrains displacement in a direction perpendicular to the X axis at positions at appropriate intervals on the extension of the X axis.
Reference numeral 46 is a heat insulating support shaft fixedly attached to the beam chamber 26, 47 is a column fixedly attached on the lower coil container 21 at an appropriate distance from the fulcrum of the heat insulating support shaft 46, and 48 is the heat insulating support shaft 46. Is a coupling member that rotatably couples the tip end of the and the shaft end of the column 47 at each fulcrum. With such a configuration, the rotational displacement of the beam chamber 26 in the mounting plane can be restrained, so that the relative reference position of the superconducting coil unit 23 is substantially fixed and the electron beam is more stable than in the case of the third embodiment. The beam chamber can be orbited, and displacement due to thermal expansion of the beam chamber can be allowed.

Example 5. FIG. 8 is a partial sectional view of a heat insulating support member of the beam chamber 26 showing an embodiment of the invention of claim 5. In the figure, reference numeral 51 denotes a plurality of support fittings provided on the side surface of the beam chamber 8. One end of each of the first and second heat insulating support members 43 and 44 is fixedly attached to the plurality of support fittings 51, and the other Since the end portions of the heat insulating support members are fixed to or abutted on the superconducting coil unit 23, the heat insulating distance of the heat insulating support member can be increased, and the first and second heat insulating support members 43, 4 from the beam chamber 26 can be extended.
The heat entering the superconducting coil unit 23 due to the heat conduction can be reduced through the No. Further, since the space of the attachment portion of the heat insulating support member can be widened, the heat insulating support portion can be easily assembled.

Example 6. FIG. 9 is a sectional view showing an embodiment of the invention of claim 6. Reference numeral 52 denotes a multiple heat insulating support column in which a plurality of cylindrical heat insulating materials are concentrically arranged, the cylindrical members are thermally separated from each other, and the ends of adjacent cylinders are alternately folded back and connected. Since one end of the cylindrical column 52 is fixed to the beam chamber 26 side, and the other end is installed in contact with or fixed to the superconducting coil unit 23, the heat insulating distance of each supporting portion becomes long, and the heat insulating support is performed. It is possible to significantly reduce the amount of heat that enters due to the heat conduction of the member. Further, since the rigidity of the heat insulating support member in the axial direction can be increased and the spring constant in the direction perpendicular to the axis can be decreased, the weight of the beam chamber 26 is rigidly supported to suppress the displacement, and thermal expansion and contraction occur in the horizontal direction. The displacement can be absorbed by the elastic deformation of the member itself, and the stress generated in the heat insulating support portion can be relaxed.

Example 7. 10 is a perspective view showing an embodiment of the invention of claim 7, and FIG. 11 is a sectional view of the central portion (A surface) of FIG. In the figure, 54 is the beam chamber 2.
The radiant heat shielding means 6 is provided so as to cover almost the entire circumference of 6, and is composed of a metal plate or the like. The radiant heat shielding means 54 connects the beam chamber 26 to the superconducting coil unit 2.
It is assumed that the beam chamber 26 is integrated with the beam chamber 26 before being combined with 3, and when the beam chamber 26 is combined with the superconducting coil unit 23 as in the above embodiment, the radiant heat shielding means 5 is used.
4 and the superconducting coil unit 23 are attached while being thermally insulated. By thus providing the radiant heat shielding means 54 in the beam chamber 26, the amount of radiant heat entering the superconducting coil unit 23 from the beam chamber 26 can be reduced, but the radiant heat shielding means 54 is previously attached to the beam chamber 26 in an integrated manner. As a result, the construction is very easy to perform, and since the final dimensions of the assembled state can be checked and combined with the superconducting coil unit 23, contact with the superconducting coil unit 23 is prevented and the heat insulation performance is reliably exhibited. be able to.

Example 8. FIG. 12 is a sectional view of a beam chamber showing an embodiment of the present invention. In this embodiment, the radiant heat shielding means of the seventh embodiment is composed of a multi-layered heat insulating material 55 and a heat shield 56 made of a metal plate.
In the figure, reference numeral 55 denotes a structure in which a reflective material having a low emissivity such as a Mylar sheet on which aluminum is vapor-deposited and a heat insulating spacer having a low thermal conductivity such as a nylon net are alternately laminated to form several to several tens layers. The multilayer laminated heat insulating material is attached by directly winding so as to cover almost the entire circumference of the surface of the beam chamber 26 with respect to the superconducting coil unit 23, and 56 is a heat shield provided so as to cover the outside of the multilayer laminated thermal insulating material 55, The divided members are connected by bolts or the like, 57 is an upper plate, 58 is a lower plate, and 59 is a side plate. 6
Reference numeral 0 denotes a plurality of heat insulating support rods which support the heat shield adiabatically with the beam chamber 26 at a constant distance. With this structure, the optimum number of layers is adjusted according to the temperature at which the beam chamber 26 and the heat shield 56 are balanced, and the gap that can be secured between the beam chamber 26 and the heat shield 56. Since the multi-layered heat insulating material can be installed and the heat shield 56 is attached by adjusting the relative position after confirming the final finished state of the multi-layered heat insulating material 55, the heat insulation can be surely performed. In this embodiment, the radiant heat shielding means 5
Although 4 is composed of both the multi-layer heat insulating material 55 and the heat shield 56, it may be composed of either one.

Example 9. FIG. 13 is a sectional view of a beam chamber showing an embodiment according to another embodiment of the invention of claim 8. In Example 8, the multi-layered heat insulating material 55 was directly wound around the beam chamber 26, but 61 is a heat-resistant heat insulating member provided between the beam chamber 26 and the multi-layered heat insulating material 55.

Usually, a baking heater 62 is installed on the wall surface of the beam chamber 26 to perform baking for releasing the residual gas on the vacuum wall surface in a short time in order to make the inside of the beam chamber 26 an ultrahigh vacuum. Finally, when the multi-layered heat insulating material 55 comes into direct contact with the high temperature portion, it may melt or burn, and the heat insulating performance may be significantly deteriorated. The heat-resistant heat-insulating member 61 is provided for this purpose, and a glass fiber tape or cloth, a high heat-resistant plastic sheet such as Kapton, a laminated plate of glass epoxy resin, or the like is suitable in consideration of the heating temperature of the beam chamber 26. Use a natural one. With such a structure, even if the beam chamber 26 is heated, deterioration of the multi-layer heat insulating material 55 does not occur, so that the required heat insulating performance can be maintained.

Example 10. FIG. 14 is another embodiment of the invention of claim 8 and is a perspective view showing a construction state of the multi-layered heat insulating material. In the figure, 63 is a first multi-layered heat insulating material which is installed by dividing the outer surface of the beam chamber 26 into approximately two parts, and 64 is an appropriate part of the other half of the beam chamber 26 that is adjacent to the first multi-layered insulating material 63. It is a second multi-layered heat insulating material attached with a large gap.

When the layers of the multi-layered heat insulating material covering the circumference of the beam chamber 26 are formed in a substantially monohedral shape as shown in FIG. 10, when the charged particles are circulated in the beam chamber 26, an aluminum vapor deposition layer is formed. An eddy current may flow and affect the detection sensitivity of various beam measurement monitors, or when the superconducting coil 1 is quenched, a large eddy current may flow and the temperature of the multi-layer heat insulating material 55 itself may rise. By dividing as described above, it is possible to reduce the eddy current loop and reduce the noise of the measurement monitor. Further, the temperature rise during quenching of the superconducting coil 1 can be mitigated.

The number of divisions and the shape of the divided pieces of the multi-layered heat insulating material may be set to an appropriate number and shape in consideration of the eddy current loop.

Example 11. An embodiment of the invention of claim 9 will be described with reference to FIG. In the figure, reference numeral 60 designates a plurality of heat insulating support rods for supporting the beam chamber 26 and the heat shield in an adiabatic manner. The heat insulating support rods 60 are composed of fiber reinforced resin laminated plates, laminated rods or pipes. The axial load is rigidly supported and the horizontal force acting between the fulcrums of the shaft is allowed to be displaced by a few millimeters so that it can be absorbed by the elastic deformation of the support rod. With such a configuration, the beam chamber 2
When the 6 and the heat shield 56 are assembled, a slight horizontal positional deviation can be absorbed by elastic deformation of each heat insulating support rod 60 itself. Further, the expansion and contraction difference due to the thermal expansion during the baking of the beam chamber 26 and the thermal contraction in the cooling process of the heat shield 56 can be absorbed by the elastic deformation of each heat insulating support rod 60 itself similarly to the above, so that the heat insulating support rod 60 is used. Therefore, excessive stress is not generated, and therefore, the heat shield 56 can be prevented from being deformed by thermal stress or the like, and further, the contact due to this deformation can be prevented.

Example 12 An embodiment of the invention of claim 10 will be described with reference to FIG. In the figure, the heat shield 56 covering the beam chamber 26 includes an upper plate 57 and a lower plate 58.
The upper plate 5 is composed of the two side plates 59.
7 and the lower plate 58 are non-magnetic metal plates having a large electric resistance,
For example, an austenitic stainless steel plate is used to form the side plate 59 with a non-magnetic metal plate having high thermal conductivity, such as a pure aluminum plate.

The operation in this case will be described. The superconducting coil 1 is arranged so that the magnetic flux penetrates in the vertical direction of the beam chamber 26, and when quenching occurs while the superconducting coil 1 is excited to generate a high magnetic field, the heat shield 56 due to a sharp magnetic field change. An eddy current flows through each of the constituent members, and an electromagnetic force having a magnitude proportional to the eddy current acts on each member. Since the eddy current is proportional to the area where the magnetic flux intersects and is inversely proportional to the specific resistance of the constituent members, a high resistance stainless steel member is applied to the upper plate 57 and the lower plate 58 where the magnetic flux intersects over a wide area, and thus the superconducting coil. The electromagnetic force that accompanies the eddy current at the time of quenching does not exceed the allowable stress of the member itself. On the other hand, the side plate 59 is arranged substantially parallel to the direction of the lines of magnetic force, and the area intersecting with the magnetic flux is much smaller than that of the upper plate 57 and the lower plate 58, and the electromagnetic force due to the eddy current can be ignored, so that pure aluminum having high thermal conductivity is used. (Small electrical resistance) is applied,
The upper plate 57 and the lower plate 58 can be cooled by using this as a heat transfer path. In this case, by forming a vertical slit in the central portion of the side plate 59, it is possible to separate the electric loop while ensuring a heat transfer path.

Heat shield 56 in Examples 8 to 12
The upper plate 57 or the lower plate 58 and the side plate 59 are overlapped with each other and fastened with a plurality of bolts.
A sheet, a film, or an adhesive tape made of polyethylene, polyimide, or the like may be sandwiched between the surfaces that come into contact with the above members. By doing so, the upper plate 57 or the lower plate 58 and the side plate 59 can be electrically insulated, so that the eddy current loop between these members can be separated.

Example 13. FIG. 15 is a perspective view of a heat shield showing another embodiment of claim 10. In the twelfth embodiment, the upper plate 57 and the lower plate 58 are each composed of one sheet, but 65 is a divided upper plate which is divided into a plurality of parts and is attached at a fixed interval, and 66 is the same as the upper plate 65. It is a divided lower plate that is divided and attached. By thus dividing and attaching the upper plate and the lower plate to each other, the eddy current flowing in each divided piece is reduced, and the electromagnetic force and heat generated on the shield member itself during quenching of the superconducting coil can be reduced.

Example 14 FIG. 16 is a plan view of a heat shield plate showing another embodiment of claim 10. In the figure, FIG. 16A shows a plurality of notches provided in the upper plate 57 and the lower plate 58 of the heat shield 56, which are alternately displaced in the direction orthogonal to the beam trajectory. By thus forming the notch, the eddy current flowing in the plate retains the same effect as in the thirteenth embodiment, and the upper plate 57 and the lower plate 58 can be handled as one member respectively, so that the parts can be easily assembled. . In FIG. 16B, a suitable number of notches are provided at appropriate intervals in the beam orbital direction and the direction orthogonal to each other while leaving the periphery of the upper plate 57 or the lower plate 58 of the heat shield 56. Since the edge is not deformed by providing the periphery in this way, the parts can be easily handled and the assembly can be performed with high accuracy.

Example 15. FIG. 17 is a perspective view and a partial sectional view of a heat shield showing an embodiment of the invention of claim 11;
FIG. 18 is a cross-sectional view of the central portion (A surface) of FIG. In the figure, the upper plate 57 and the lower plate 58 of the heat shield 56 are non-magnetic stainless steel plates constructed in the same manner as in the twelfth embodiment, and 67 is cut into an appropriate size to make a plurality of them.
Alternatively, a metal plate having a large thermal conductivity, which is arranged on the lower plate 58 at a suitable interval, such as a copper heat transfer plate, 68 is an adhesive agent for bonding the upper plate 57 or the lower plate 58 and a plurality of heat transfer plates 67, 69 Is a plurality of fixing screws provided at appropriate intervals so that the adhesive surface of the tropical plate 67 does not peel off. As the fixing screw 69, a laminated bar of polycarbonate or glass epoxy resin or the like is used in consideration of electric insulation and heat insulation.

As described above, since the upper plate 57 or the lower plate 58 and the heat transfer plate 67 are formed of a thin adhesive layer, an electrically insulating or large electric resistance layer can be formed. By properly selecting the mounting interval, the eddy current loop can be made small and the electromagnetic force induced when the superconducting coil 1 is quenched can be made sufficiently small. Further, since the thickness of the adhesive layer between the heat transfer plate 67 and the upper plate 57 or the lower plate 58 can be set to 0.1 to 0.2 mm or less, the thermal resistance here is sufficiently small. With such a structure, deformation of the heat shield due to electromagnetic force during quenching of the superconducting coil is suppressed, and the upper plate 57 and the lower plate 58 of the heat shield are formed by the tropical plate 6.
By cooling one end of 7, it is possible to perform cooling by heat conduction using the tropical heat transfer plate 67 as a heat transfer path. In this case, if the heat transfer plate 67 is divided into two in the central portion, it is possible to avoid the formation of an eddy current loop while ensuring a heat transfer path.

Further, thin fibers or cloth of glass may be laid in a mat shape on the bonding portion between the upper plate 57 or the lower plate 58 and the heat transfer plate 67 and fixed with the adhesive 68.
By doing so, the upper plate 57 or the lower plate 58
Since it is possible to prevent direct contact between the heat transfer plate 67 and the heat transfer plate 67, it is possible to ensure electrical insulation.

In the fifteenth embodiment, the heat shield 56 is used.
Although the side plate 60 of is made of a material having a high heat conductivity such as aluminum, if the heat transfer path can be sufficiently secured by the heat transfer plate 67, the whole heat shield is made of a non-magnetic metal plate having a large electric resistance. It may be configured to cover.

Example 16. FIG. 19 is a perspective view of a heat shield showing another embodiment of the invention of claim 11. In the sixteenth embodiment, the tropical plate 68 is installed in a direction parallel to the beam orbit of the beam chamber 26, but 70 is a tropical plate provided in a direction orthogonal to the beam orbit of the beam chamber 26. With such a configuration, the side plate 60
Since the upper plate 58 and the lower plate 59 can be cooled by using as a heat transfer path, the average temperature of the shield can be lowered by the amount that the thermal resistance is reduced.

Example 17 FIG. 20 is a cross-sectional view showing an embodiment of the invention of claim 12, in which reference numeral 71 constitutes an expanding / contracting portion of a first bellows joint 41 (see FIG. 3) provided at both ends of the beam chamber 26. The first bellows, 72 is a first flange having two sealing grooves on the end face of the first bellows joint 71, and 73 is the beam inlet port 8 or the beam outlet port 9 of the vacuum chamber 5, respectively. Relay flange for connecting the flange 72, 7
4 is a first vacuum seal mounted inside the two sealing grooves of the first flange, 75 is a second vacuum seal mounted outside the two sealing grooves, and 76 is a through hole of the relay flange 73. The first flange 72 and the first vacuum seal 74
And a plurality of fixing bolts for applying and sealing the necessary sealing surface pressure to the second vacuum seal 75, and 77 denotes the beam inlet port 8 or the beam outlet port 9 and the relay flange 73.
It is a third vacuum seal for sealing and. Here, the relay flange 73 is made of a material having a low emission gas rate, for example, a vacuum melting material of austenitic stainless steel or the like, considering that it constitutes a part of an ultrahigh vacuum beam duct. Such a configuration can be applied to the emitted light port 10.

With this structure, the first vacuum seal 74 of the first flange 72 is on the ultra-high vacuum side inside the beam chamber, and the second vacuum seal 75 is on the adiabatic vacuum side of the vacuum chamber 5, respectively. Since they are sealed independently, it is possible to blow helium gas from the atmosphere side when performing a helium leak test by vacuuming each system. Therefore, it is possible to prevent the inflow of helium gas, which is a kind of gas that is difficult to be exhausted in the vacuum portion, particularly in the vacuum exhaust on the ultra-high vacuum side, so that the ultra-high vacuum can be easily achieved. In addition, a vacuum chamber 5 which does not require an ultra-high vacuum is formed by applying a material with a small amount of released gas only to the portion forming the ultra-high vacuum.
A magnetic material such as pure iron can be applied to form part of the magnetic shield, and the superconducting electromagnet can be rationally designed.

Example 18. 21 is a sectional view showing another embodiment of the invention of claim 12. In FIG. In the seventeenth embodiment, the first flange 72 is provided with the double vacuum seal, but in the figure, the first flange 72 is provided with only the first vacuum seal, and instead, a plurality of relay flanges 73 are fixed. The counterbore part of the bolt head of the bolt 76 is provided with another stepped screw hole, 78 is a plurality of packings respectively mounted on the seating surfaces of the screw holes, and 79 is abutted against the packing 78 to provide an appropriate surface pressure. It is a sunk bolt that adds a vacuum to seal the vacuum. With this configuration, the first
Since the second vacuum seal of the flange is eliminated, the outer shape of the flange can be made small, and since the tightening force of the seal is reduced, there is a margin in the strength design of the flange, and the size of the flange can be made one size smaller.

Example 19 22 is a sectional view showing another embodiment of the invention of claim 12. In FIG. Although the end surface of the relay flange 73 is located outside the inner wall surface of the vacuum chamber 5 in Embodiments 19 and 20 above,
In FIG. 22, the end surface of the relay flange 73 is projected inward from the inner wall surface of the vacuum chamber 5. With such a configuration, when the beam chamber 26 is attached to the vacuum chamber 5, the first bellows 7 of the bellows joint is attached.
1 to compress the first flange 7 of the beam chamber 26.
When the relay flange 73 is removed when a gap is provided between the end face of 2 and the inner wall surface of the vacuum chamber 5, a sufficient gap can be secured and the workability of assembly is facilitated. Further, the first bellows can be made to have a short expansion / contraction amount, that is, a bellows having a small number of peaks.

Example 20. FIG. 23 is a sectional view of a superconducting electromagnet according to an embodiment of the invention of claim 13. In the figure, 81 is a plurality of cooling jackets provided in contact with the outer wall surface of the beam chamber 26, 82 is a connecting pipe for the cooling jackets 81 arranged in a distributed manner, and 83 is adiabatic guide through the vacuum chamber 5. Refrigerant piping, 84 is a general-purpose refrigerator using Freon as a refrigerant.

In the configuration as described above,
In the cooling jacket 81 of the beam chamber 26, a refrigerant such as CFC is circulated through a refrigerant pipe 83 from a general-purpose refrigerator 84 provided outside the vacuum chamber 5 of the superconducting electromagnet 11, so that the beam chamber 26 has a predetermined temperature, for example. ,
It is designed to be cooled from -15 ° C to -30 ° C. With such a structure, the heat entering the superconducting coil unit 23, which is cooled and held at 4K from the wall surface of the beam chamber 26, can be reduced, and accordingly, the liquid helium cooling the superconducting coil 1 to 4K can be reduced. Evaporation loss can be reduced. Further, since the amount of gas released from the inner wall surface of the beam chamber 26 is reduced by lowering the wall temperature of the beam chamber 26, the ultimate pressure of the ultrahigh vacuum can be reduced.

In the above embodiment, a cooling jacket is provided on the wall surface of the beam chamber 26 for cooling, but the cooling pipe is directly contacted and wound with an appropriate interval according to the shape of the wall surface. May be.

[0068]

As described above, according to the invention of claim 1, the beam chamber for passing charged particles is independently provided in the vacuum chamber of the superconducting coil. Even if the degree of vacuum changes due to such disturbances, the inside of the beam chamber can be maintained at the desired ultra-high vacuum. As a result, instability factors of the charged beam, such as collision and scattering of the high energy charged beam circulating in the beam chamber with residual gas molecules, can be suppressed, and the accumulated charged beam can be stably rotated for a long time. Further, even if the beam chamber is opened to the atmosphere, it does not affect the adiabatic vacuum of the superconducting coil, so that the superconducting electromagnet can be operated stably regardless of the vacuum on the beam chamber side.

According to the second aspect of the present invention, the plurality of radiant light ducts are thermally insulated from the side surface of the beam chamber with the superconducting coil unit, and a vacuum seal is provided at a portion penetrating the vacuum chamber to take out radiant light. I did so,
Even if the degree of vacuum on the side of the superconducting coil changes, the synchrotron radiation can be stably extracted without being affected by the inside of the radiation duct. Further, even if the radiant light duct side is opened to the atmosphere, the vacuum in the adiabatic vacuum portion of the superconducting coil is not deteriorated, so that the superconducting electromagnet can be operated regardless of the vacuum in the radiant light duct system.

According to the third aspect of the invention, the beam chamber is adiabatically supported on the wall surface of the superconducting coil container by a heat insulating support member at a constant interval, and a plurality of ports of the beam chamber penetrate the wall surface of the vacuum chamber. Since each part is equipped with an elastic bellows joint,
A beam chamber can be installed along the beam trajectory of the charged particles, and the charged particles can be stably circulated.

In the invention of claim 4, one or two fixed positions of the heat insulating support member for supporting the beam chamber, which serve as a reference relative to the superconducting coil container, are fixedly supported, and Since a plurality of points are adiabatically supported so that the distance between them is almost constant, the relative position and parallelism between the superconducting coil and the beam chamber can be kept substantially constant and the charged particles can be stably circulated. .

According to the fifth aspect of the present invention, since the supporting metal fitting is provided on the side surface of the beam chamber and the heat insulating supporting member is attached to the supporting metal fitting so as to support the wall of the superconducting coil container adiabatically, the heat insulating supporting member is attached. The span can be lengthened, and the amount of heat entering due to heat conduction through the heat insulating support member can be reduced. In addition, the installation space is wide and the workability of assembly is improved.

In the sixth aspect of the present invention, since the heat insulating support member of the beam chamber is constituted by the multiple cylindrical heat insulating column, the heat insulating distance can be made twice as long as the mounting span length or more, and the heat insulating performance can be significantly improved. Can be improved. Also,
Since the heat insulating support member is rigidly supported in the axial direction and a displacement of several millimeters in the direction perpendicular to the axis at the fulcrums at both ends can be absorbed by elastic deformation, the distance between the beam chamber and the superconducting coil container is kept constant. It has an effect of being able to hold it and absorbing the displacement caused by thermal expansion / contraction during heating of the beam chamber during baking and cooling of the superconducting coil by elastic deformation to alleviate thermal stress.

According to the invention of claim 7, since the heat radiation shielding means is integrally attached to the beam chamber in advance, the construction becomes very easy, and the final dimension of the assembled state is confirmed and the superconducting coil is confirmed. Since they can be combined, they have great practical effects such as preventing thermal contact and ensuring heat insulation performance.

In the eighth aspect of the invention, since the multilayer laminated heat insulating material is directly attached to the beam chamber and a heat shield is provided so as to substantially surround the circumference of the beam chamber, the integrated one is combined with the superconducting coil. Is very easy to do. In addition, the optimum number of layers is adjusted in the gap between the beam chamber and the heat shield to install the multi-layered heat insulating material, the final finish state is confirmed, and the relative position of the heat shield can be adjusted to install. It has the effect of ensuring the heat insulation performance of.

According to a ninth aspect of the present invention, a plurality of heat insulating support rods supported by the heat shield of the beam chamber are rigidly supported in the axial direction by using laminated rods or pipes of fiber reinforced resin, and the shaft orthogonal direction at both ends of the shaft. Since the displacement of several millimeters can be absorbed by elastic deformation, the self-weight of the heat shield is rigidly supported and the gap between the superconducting coil container and the heat shield can be kept constant to prevent thermal contact and heat shield. Since the expansion difference due to the contraction of the plate can be absorbed by the elastic deformation of the heat insulating support rod, the thermal stress through the supporting portion of the heat shield can be relieved and the deformation of the shield plate itself can be suppressed, thereby preventing thermal contact. And so on.

In the tenth aspect of the present invention, the shield plate covering the surface of the heat shield member of the superconducting electromagnet in the direction substantially intersecting with the magnetic flux is provided with a non-magnetic metal plate having a large electric resistance, and the surface is substantially parallel to the magnetic flux. Since a non-magnetic metal plate with low thermal resistance is placed as the shield plate that covers the magnetic field, even if a sudden magnetic field change occurs due to quenching of the superconducting coil, the electromagnetic force caused by the eddy current induced in the heat shield member is prevented. It can be kept small to prevent deformation of the shield plate itself. Further, since a member having a small heat resistance can be used as a heat transfer path to cool a member having a high resistance, the average cooling temperature of the shield can be lowered.

In the invention of claim 11, the heat shield plate is made of a non-magnetic metal plate having a large electric resistance and a non-magnetic metal transfer plate having a suitable shape having a small heat resistance, which is integrated by adhesion. The eddy current flowing through the heat shield is small even when the magnetic field changes rapidly during quenching of the superconducting coil, and therefore the electromagnetic force generated in the heat shield itself can be reduced. In addition, since a plurality of heat transfer plates can be appropriately dispersed on the heat shield plate to be cooled, the whole heat shield can be cooled uniformly.

In a twelfth aspect of the present invention, a vacuum chamber, a superconducting coil unit provided with a space for guiding charged particles in a predetermined orbit in the vacuum chamber, and a space for the superconducting coil unit are thermally provided. A beam chamber that guides charged particles to be separated from each other, and a plurality of beam ducts communicating with the wall surface of the beam chamber are provided with relay flanges at portions where they penetrate the vacuum chamber, and a sealing surface of the relay flange and the beam chamber. It is possible to easily achieve an ultrahigh vacuum in the portion through which the charged beam is passed, in which the end surface of the beam duct and the sealing surface of the through hole of the vacuum chamber are connected via a vacuum seal. Also, due to the above division, it can be applied to a part of the magnetic shield that suppresses the leakage magnetic field from the superconducting coil that generates a high magnetic field using a magnetic material such as pure iron to a vacuum chamber that does not require an ultrahigh vacuum. In addition, there is an effect that the superconducting electromagnet can be designed rationally.

In the thirteenth aspect of the invention, the beam chamber integrated with the superconducting coil is circulated through a refrigerant or a liquefied gas of a general-purpose refrigerator to add a simple and highly reliable cooling system for cooling. Therefore, there is an effect that the heat entering the superconducting coil side can be reduced and the evaporation amount of expensive liquid helium can be reduced.

[Brief description of drawings]

FIG. 1 is a view showing a longitudinal section of a superconducting electromagnet for charged particles according to an embodiment of the invention of claims 1 and 2.

FIG. 2 is a diagram showing a horizontal section of FIG.

FIG. 3 is a horizontal sectional view showing a superconducting electromagnet according to an embodiment of the present invention.

FIG. 4 is a sectional view of a portion (A-A) in FIG.

FIG. 5 is a partial cross-sectional view of a heat insulating support part of a beam chamber of a superconducting electromagnet for charged particles according to an embodiment of the invention of claim 4;

FIG. 6 is a plan view of a heat insulating support structure of a beam chamber of a superconducting electromagnet for charged particles according to another embodiment of the present invention.

7 is a partial cross-sectional view (AA) of the heat insulating support of the beam chamber of FIG.

FIG. 8 is a sectional view of a heat insulating support structure of a beam chamber of a superconducting electromagnet for charged particles according to an embodiment of the fifth aspect.

FIG. 9 is a sectional view of a heat insulating support portion of a beam chamber of a superconducting electromagnet for charged particles according to an exemplary embodiment of the present invention.

FIG. 10 is a perspective view showing a heat insulating structure of a beam chamber of a superconducting electromagnet for charged particles according to an embodiment of the present invention.

11 is a perspective view of a central portion (A surface) of FIG.

FIG. 12 is a cross-sectional view of a heat shield of a superconducting electromagnet for charged particles according to an embodiment of the invention of claims 8 and 9 to 10.

FIG. 13 is a sectional view of a heat shield of a superconducting electromagnet for charged particles according to another embodiment of the invention of claim 8;

FIG. 14 is a perspective view showing a construction appearance of a multi-layered heat insulating material for a superconducting electromagnet for charged particles according to an embodiment of the present invention.

FIG. 15 is a perspective view of a heat shield of a superconducting electromagnet for charged particles according to another embodiment of the present invention.

FIG. 16 is a perspective view of a heat shield plate of a superconducting electromagnet for charged particles according to another embodiment of the invention of claim 10;

FIG. 17 is a perspective view and a partial sectional view of a heat shield of a superconducting electromagnet for charged particles according to an embodiment of the invention of claim 11;

18 is a partial cross-sectional view of the central portion (A surface) of FIG.

FIG. 19 is a perspective view of a heat shield of a superconducting electromagnet for charged particles according to another embodiment of the invention of claim 11;

FIG. 20 is a partial cross-sectional view showing the structure of the joint portion of the beam chamber of the superconducting electromagnet for charged particles according to the embodiment of the invention of claim 12;

FIG. 21 is a partial cross-sectional view showing the structure of the joint portion of the beam chamber of the superconducting electromagnet for charged particles according to another embodiment of the invention of claim 12;

FIG. 22 is a partial cross-sectional view showing the structure of the joint portion of the beam chamber of the superconducting electromagnet for charged particles according to another embodiment of the twelfth aspect of the present invention.

FIG. 23 is a sectional view showing a superconducting electromagnet for charged particles according to an embodiment of the present invention.

FIG. 24 is a bird's-eye view of a bending electromagnet for an electron storage ring showing an example of a conventional superconducting electromagnet for charged particles.

25 is a vertical cross-sectional view of the central portion of FIG. 24.

26 is a horizontal sectional view of the electron beam orbit of FIG. 24.

FIG. 27 is a perspective view showing a shape appearance of the superconducting coil portion of FIG. 25.

FIG. 28 is a structural conceptual diagram of an electron storage ring showing an example of application of a conventional superconducting electromagnet for charged particles.

[Explanation of symbols]

 1 Superconducting Coil 2 Coil Container 3 Electron Beam Passage 4 Heat Shield 5 Vacuum Tank 6 Adiabatic Support Member 7 Helium Supply Port 8 Beam Inlet Port 9 Beam Outlet Port 10 Multiple Synchrotron Ports 11 Superconducting Magnets 12 Beam Injector 13 High Frequency Cavity 14 Straight Line Part beam duct 20 Upper coil container 21 Lower coil container 22 Low temperature electromagnetic force support 23 Superconducting coil unit 24 Z-axis heat insulating support 25 X-axis heat insulating support 26 Beam chamber 27 Flange joint 28 Radiant light duct A 31 Magnetic shield 32 Radiant light Duct B 33 Vacuum gate valve 34 Liquid helium reservoir 35 Helium vacuum tank 36 Helium pipe A 37 Helium pipe B 41 First bellows joint 42 Second bellows joint 43 First heat insulating support member 44 Second heat insulating support member 45 Second Disconnection of 3 Support member 46 Heat insulating support shaft 47 Strut 48 Connecting member 51 Plural support metal fittings 52 Multiple heat insulating support column 54 Radiant heat shielding means 55 Multiple laminated heat insulating material 56 Heat shield 57 Upper plate 58 Lower plate 59 Side plate 60 First heat insulating support rod 61 High-temperature heat insulating member 62 Sheath heater 63 First multi-layered heat insulating material 64 Second multi-layered heat insulating material 65 Divided upper plate 66 Divided lower plate 67 Transferring plate 68 Adhesive 69 Fixing screw 70 Transferring plate B 71 First bellows 72 First flange 73 Relay flange 74 First vacuum seal 75 Second vacuum seal 76 Fixing bolt 77 Third vacuum seal 78 Plural packing 79 Sinking bolt 81 Cooling jacket 82 Communication pipe 83 Refrigerant piping 84 General-purpose refrigerator

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshie Takeuchi 8-1-1 Tsukaguchihonmachi, Amagasaki City Mitsubishi Electric Corporation Central Research Institute (72) Inventor Shunji Yamamoto 8-1-1 Tsukaguchihonmachi, Amagasaki Mitsubishi Electric Central Research Institute Co., Ltd. (72) Inventor Tadatoshi Yamada 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Central Research Institute (72) Inventor Shiro Nakamura 8-1-1 Tsukaguchi Honmachi, Amagasaki Mitsubishi Electric Corporation Central Research Laboratory (72) Inventor Akinori Ohara 8-1-1 Tsukaguchihonmachi, Amagasaki City Mitsubishi Electric Corporation Central Research Laboratory (72) Inventor Masao Morita 8-1-1 Tsukaguchihonmachi, Amagasaki Mitsubishi Electric Corporation Central Research In-house (72) Inventor Shoichi Yokoyama 8-1-1 Tsukaguchihonmachi, Amagasaki City Central Research Laboratory, Mitsubishi Electric Corporation (72 ) Inventor Kenji Shimohata 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Co., Ltd. Central Research Laboratory (72) Inventor Takashi Inaguchi 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Central Research Laboratory (72) Invention Person Kao Senoo 8-1-1 Tsukaguchihonmachi, Amagasaki-shi Central Research Laboratory, Mitsubishi Electric Corporation

Claims (14)

[Claims] 1. A vacuum chamber, a pair of superconducting coils which are provided in the vacuum chamber and which form trajectories of charged particles, and a pair of superconducting coils which are housed in a pair of coil containers together with liquid helium, respectively. A superconducting coil unit that is thermally insulated and arranged in the vacuum chamber, a beam chamber that is thermally insulated and arranged in a space between a pair of coil containers of the superconducting coil unit, and that allows charged particles to pass therethrough; A superconducting electromagnet apparatus for charged particles, characterized in that a joint provided with a vacuum seal is provided at a portion penetrating the vacuum chamber and opened to make a vacuum space of a vacuum structure and a vacuum space in a beam chamber independent. 2. A joint provided with a radiant light duct for extracting radiant light in a tangential direction of a charged particle trajectory on a side wall of an outer peripheral portion of the beam chamber, and a vacuum seal provided at a portion where the radiant light duct penetrates the vacuum chamber. The superconducting electromagnet apparatus for charged particles according to claim 1, wherein a vacuum space in the vacuum chamber and a vacuum space in the beam chamber are independent from each other by providing an opening. 3. A heat insulating support member for heat-insulating and supporting the superconducting coil unit in the vacuum chamber, an electromagnetic force supporting member for supporting an electromagnetic force generated between a pair of coil containers of the superconducting coil unit, and the beam. A plurality of heat-insulating support members for heat-insulating and supporting the chamber in a space between the pair of coil containers of the superconducting coil, and a vacuum seal at both ends of the beam chamber and / or a portion where the radiant light duct penetrates the vacuum chamber. The superconducting electromagnet apparatus for charged particles according to claim 1 or 2, characterized in that the heat insulating support member is provided with an expandable joint, and the heat insulating support member for heat insulating and supporting the beam chamber is slidable in a horizontal plane. 4. A variation in the position of the beam chamber is limited by limiting a range in which a small number of a plurality of heat insulating support members that thermally support the beam chamber can slide. Claim 1
The superconducting electromagnet apparatus for charged particles according to any one of 1 to 3. 5. The beam chamber according to claim 1, wherein a plurality of support fittings are provided on a side surface of the beam chamber, and the heat insulating support member of the beam chamber is supported by the support fittings. Superconducting electromagnet device for charged particles. 6. The superconducting electromagnet apparatus for charged particles according to claim 1, wherein the heat insulating support member of the beam chamber is composed of a multi-cylinder heat insulating column. 7. The radiant heat shielding means for covering substantially the entire surface of the beam chamber facing the superconducting coil unit is integrally provided in the beam chamber. Superconducting electromagnet device for charged particles. 8. The radiant heat shielding means covers substantially the entire surface of the beam chamber, and a heat shield formed of a metal plate box having a heat insulating support member for thermally insulating and supporting the beam chamber or wound around the beam chamber. The superconducting electromagnet apparatus for charged particles according to any one of claims 1 to 7, wherein the superconducting electromagnet apparatus for charged particles comprises at least one of a multi-layered heat insulating material separated from the heat shield. 9. The heat insulating support member for supporting the beam chamber on the heat shield is made of a flexible fiber-reinforced resin laminated plate, laminated rod or laminated pipe. The superconducting electromagnet apparatus for charged particles according to claim 1. 10. A member of the heat shield in a direction intersecting with the main magnetic field of the superconducting coil is made of a non-magnetic metal plate having a large electric resistance, and a member in a direction parallel to the main magnetic field is made of non-magnetic heat. The superconducting electromagnet device for charged particles according to any one of claims 1 to 9, wherein the superconducting electromagnet device is composed of a metal plate having high conductivity. 11. At least a part of the heat shield is made of a non-magnetic metal plate member having a large electric resistance, and a heat transfer plate made of a non-magnetic metal having a large thermal conductivity is provided on the plate member. The superconducting electromagnet apparatus for charged particles according to any one of claims 1 to 10, wherein the superconducting electromagnet apparatus is electrically insulated and bonded. 12. A vacuum flange for sealing the relay flange and the end face of the beam duct of the beam chamber, wherein a relay flange is provided in each of the beam duct portions that penetrate the vacuum chamber of the beam chamber, and the relay flange and the vacuum chamber. The superconducting electromagnet apparatus for charged particles according to any one of claims 1 to 11, further comprising: a vacuum seal that seals the through hole of the. 13. A cooling unit comprising a cooling jacket or a cooling pipe is provided on a wall surface of the beam chamber, and the cooling unit and a refrigerator provided outside the vacuum chamber are connected by a heat insulating pipe penetrating the vacuum chamber. The superconducting electromagnet device for charged particles according to any one of claims 1 to 12. 14. An electron storage ring using the superconducting electromagnet for charged particles according to any one of claims 1 to 13.