Cyclotron and associated magnet coil and coil fabricating process

• US 5,463,291 A
• Filed: 12/23/1993
• Issued: 10/31/1995
• Est. Priority Date: 12/23/1993
• Status: Expired due to Term

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: CTI Cyclotron Systems
• Inventors: Picker, Franck, Hendry, George, Carroll, Lewis
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): RICHARDSON, LAW
• Application Number:
  US08/178,375
• Time in Patent Office: 677 Days
• Field of Search: 328/234, 335/210, 315/502
• US Class Current: 315/502
• CPC Class Codes: H05H 13/00 Magnetic resonance accelerators; Cyclotrons strophotrons, turbine tubes H01J25/62
• CPC Class Codes: H05H 7/04 Magnet systems , e.g. undulators, wigglers free-electron laser H01S3/0903; Energisation thereof
• CPC Class Codes: Y10T 29/4902 Electromagnet, transformer or inductor
• CPC Class Codes: Y10T 29/49071 by winding or coiling

Abstract

A cyclotron and associated magnet coil and coil fabricating process. The cyclotron (10) includes a return yoke (12) defining a cavity (28) therein. A plurality of wedge-shaped regions called "hills" (29) are disposed in the return yoke (12), and voids called "valleys" (34) are defined between the hills (29). A single, substantially circular magnet coil (40) surrounds and axially spans the hills (29) and the valleys (34). The cyclotron magnet coil fabricating process includes the steps of securing a first end portion of a continuous length of sheet conductor to a substantially circular base, and positioning a first end portion of a length of insulator material coated on opposite sides with a thermosetting resin between the first end portion of the sheet conductor and the base. The length of sheet conductor and the length of insulator material are then wound about the base, and the magnet coil is heated to a temperature sufficient to cause the thermosetting resin to flow and wet adjacent turns of the sheet conductor.

Claims

1. A cyclotron comprising:

a return yoke provided with a cavity therein;

a plurality of hill regions within said return yoke, each said hill region defining an upper hill section and a lower hill section separated by a first air gap for accommodating a particle beam, said hill regions being selectively spaced so as to provide valley regions therebetween defining further air gaps greater in width than said first air gaps; and

a substantially circular magnet coil surrounding said hill regions and said valley regions, said coil defining a coil body including coil windings, and having at least one beam exit hole extending through said coil body for accommodating the exiting of a particle beam from said cyclotron.

2. The cyclotron of claim 1 wherein said return yoke includes an upper yoke portion and a lower yoke portion selectively spaced from said upper yoke portion, and wherein said magnet coil defines an axial dimension substantially spanning the distance between said upper yoke portion and said lower yoke portion.

3. The cyclotron of claim 1 wherein said magnet coil includes windings of sheet conductor with sheet insulator material disposed between turns of said sheet conductor.

4. The cyclotron of claim 1 wherein said magnet coil includes coil windings defining a continuous winding of sheet conductor with a continuous length of sheet insulator material disposed between turns of said sheet conductor.

5. The cyclotron of claim 2 wherein said magnet coil includes coil windings defining a continuous winding of sheet conductor with a continuous length of sheet insulator material disposed between turns of said sheet conductor.

6. The cyclotron of claim 3 wherein said sheet insulator material defines opposing surfaces coated with a bonding material.

7. The cyclotron of claim 4 wherein said sheet insulator material defines opposing surfaces coated with a bonding material.

8. The cyclotron of claim 7 wherein said sheet insulator material is a polymer film.

9. The cyclotron of claim 7 wherein said bonding material is a thermosetting resin.

10. The cyclotron of claim 7 wherein said sheet insulator material is a polymer film and said bonding material is a thermosetting resin.

11. A magnet coil for a cyclotron, said coil comprising a base member and a continuous winding of sheet conductor disposed about said base member with a continuous length of sheet insulator material disposed between turns of said sheet conductor, said magnet coil defining at least one beam exit hole extending through said coil for accommodating the exiting of a particle beam from said cyclotron.

12. The magnet coil of claim 11 wherein said sheet insulator material defines opposing surfaces coated with a bonding material.

13. The magnet coil of claim 11 wherein said sheet insulator material is a polymer film.

14. The magnet coil of claim 12 wherein said bonding material is a thermosetting resin.

15. The magnet coil of claim 12 wherein said sheet insulator material is a polymer film and said bonding material is a thermosetting resin.

16. A magnet coil for a cyclotron, said cyclotron having a return yoke provided with a cavity therein and a plurality of hill regions within said return yoke, each said hill region defining an upper hill section and a lower hill section separated by a first air gap for accommodating a particle beam, said hill regions being selectively spaced so as to provide valley regions therebetween defining further air gaps greater in width than said first air gaps, said magnet coil comprising:

a cylindrical magnet coil surrounding, and defining an axial dimension for substantially spanning, said hill regions and said valley regions of said cyclotron, said coil defining a coil body including coil windings, and having at least one beam exit hole extending through, and formed in, said coil windings for accommodating the exiting of a particle beam from said cyclotron.

17. A magnet coil fabricating process for fabricating a magnet coil for a cyclotron, said process comprising the steps of:

securing a first end portion of a length of sheet conductor to a substantially circular base member;

positioning a first end portion of a length of insulator material coated on opposite sides with a bonding material between said first end portion of said length of sheet conductor and said base member;

winding said length of sheet conductor and said length of insulator material about said base member; and

boring at least one beam exit hole through said coil.

18. A magnet coil fabricating process for fabricating a magnet coil for a cyclotron, said process comprising the steps of:

securing a first end portion of a continuous length of sheet conductor to a cylindrical base member;

positioning a first end portion of a continuous length of insulator material coated on opposite sides with a bonding material between said first end portion of said length of sheet conductor and said base member, said insulator material comprising a polymer film and said bonding material comprising a thermosetting resin;

winding said length of sheet conductor and said length of insulator material about said base member;

heating said magnet coil to a temperature sufficient to cause said thermosetting resin to flow and wet adjacent turns of said sheet conductor;

allowing said thermosetting resin to cool whereby said thermosetting resin hardens and bonds adjacent turns of said sheet conductor with said insulator material interposed therebetween; and

boring at least one beam exit hole through said sheet conductor and said insulator material of said coil.

19. The coil fabricating process of claim 18 wherein said process comprises the further step of chemically etching the edges of said sheet conductor abutting said beam exit hole such that said edges of said sheet conductor abutting said beam exit hole lie behind adjacent layers of said insulator material.