Product irradiator

• US 6,215,847 B1
• Filed: 09/15/1998
• Issued: 04/10/2001
• Est. Priority Date: 09/15/1998
• Status: Expired due to Term

• Current Assignee: Nordion Incorporated
• Original Assignee: MDS Nordion Inc. (Nordion Incorporated)
• Inventors: Perrins, Rob, Gerwing, Dave
• Primary Examiner(s): Bruce, David V.
• Assistant Examiner(s): Dunn, Drew A.
• Application Number:
  US09/153,669
• Time in Patent Office: 938 Days
• Field of Search: 378/68, 378/69, 378/64, 250/453.11, 250/454.11
• US Class Current: 378/69
• CPC Class Codes: A61L 2/0035 Gamma radiation
• CPC Class Codes: A61L 2/08 Radiation
• CPC Class Codes: A61L 2202/122 Chambers for sterilisation
• CPC Class Codes: A61L 2202/24 Medical instruments, e.g. endoscopes, catheters, sharps
• CPC Class Codes: G21K 5/10 with provision for relative movement of beam source and object to be irradiated

Abstract

The present invention is directed to a product irradiator comprising a loading-unloading area and an irradiation chamber, a continuous track having a level-changing portion, wherein the continuous track enters and exits the irradiation chamber from the loading-unloading area. The continuous track is comprised of at least one rail and of at least two levels to about 8 levels. An irradiation source, for example cobalt 60, and which is preferably horizontal in orientation, is located within the irradiation chamber. The product irradiator comprises a substantially horizontal carrier, which is engaged to the continuous track, and at least one drive mechanism capable of moving the carrier along the continuous track.

Claims

1. A product irradiator comprising:

i) a loading-unloading area and an irradiation chamber;

ii) a continuous, substantially elongated helical track having a level-changing portion, said continuous track entering and exiting said irradiation chamber from said loading-unloading area, said continuous track comprised of at least one rail and of at least two levels;

iii) a radiation source located within said irradiation chamber;

iv) a substantially horizontal carrier engaged to said at least one rail; and

v) at least one drive mechanism capable of moving said carrier along said continuous track.

2. The product irradiator of claim 1, wherein said radiation source is either cobalt 60 or cesium 137.

3. The product irradiator of claim 2, wherein said continuous track comprises up to eight levels within said irradiation chamber.

4. The product irradiator of claim 3, wherein said continuous track is bar-bell shaped track.

5. The product irradiator of claim 3, wherein said radiation source is centrally positioned within said elongated helical track.

6. The product irradiator of claim 5, wherein said source lies in a substantially horizontal rack within said irradiation chamber.

7. The product irradiator of claim 5, wherein said elongated helical track comprises either two, four six or eight levels.

8. The product irradiator of claim 7, wherein said radiation source is positioned with an equivalent number of said levels of elongated helical track lying above said radiation source, as levels of elongated helical track that lie below said radiation source.

9. The product irradiator of claim 8, further comprising a product re-orienting mechanism.

10. The product irradiator of claim 9, wherein said radiation source adopts a product-overlapping-source configuration.

11. The product irradiator of claim 10, wherein said substantially horizontal carrier is engaged to said at least one rail by a wheel assembly, said wheel assembly is pivotally attached along one side of each of said horizontal carrier.

12. The product irradiator of claim 1, wherein said continuous track is comprised of two rails.

13. The product irradiator of claim 12, wherein said rails are offset with respect to each other.

14. The product irradiator of claim 1, wherein said radiation source is comprised of source modules.

15. The product irradiator of claim 14, wherein said radiation source is stored below the irradiation chamber.

16. The product irradiator of claim 14, wherein said radiation source is brought into a substantially horizontal position within said irradiation chamber using a source rack hoist and guide assembly.

17. The product irradiator of claim 1, wherein said irradiation chamber is temperature controlled and ranges from about −

25°

C. to about 25°

C.

18. The product irradiator of claim 1, wherein said irradiation chamber is located within a building comprising concrete, lead, or both concrete and lead, walls and roof.

19. The product irradiator of claim 18, wherein said roof further comprises a multipiece roof plug, permitting access to said irradiation chamber.

20. The product irradiator of claim 19, further comprising a maze located between said loading-unloading area and irradiation chamber, said continuous track travelling through said maze.

21. The product irradiator of claim 1, wherein said carrier travels along said continuous track at different speeds.

22. The product irradiator of claim 1, wherein at least one, of said at least one drive mechanism, comprises a chain drive with a plurality of outwardly extending pins, each of said plurality of outwardly extending pins capable of engaging with a dog attached to said carrier and pivotally biased in the direction of the chain drive, so that when said dog is engaged with one of said plurality of outwardly extending pins, said carrier is moved along said continuous track by said chain drive.

23. The product irradiator of claim 22, further comprising a stop link capable of disengaging said dog from one of said outwardly extending pins, thereby permitting said carrier to stop along said continuous track.

24. The product irradiator of claim 23, wherein said stop link is attached to the rear of said carrier, and said dog is attached to the front of said carrier, so that when two carriers abut each other, said dog disengages with said drive chain.

25. The product irradiator of claim 1, wherein the height of said carrier, with respect to said continuous track, can be altered by a height adjust mechanism.

26. The product irradiator of claim 25, wherein the height adjust mechanism is a screw mechanism, a ramp mechanism, a piston-driven mechanism, a ratchet mechanism, or a combination thereof.

27. The product irradiator of claim 1, characterized with a dose-uniformity-ratio of up to about 2.2 for a product having a density of about 0.01 to about 0.9 g/cc, and said product between from about 6 to 36 inches in height.

29. The product irradiator of claim 9, further comprising at least two carriers, wherein said product re-orienting mechanism comprises a pusher capable of transferring said product from a first carrier to a second carrier.

30. The product irradiator of claim 1, wherein said carrier is insulated.

28. A product irradiator comprising:

i) a temperature controlled building, within which is located a loading-unloading area, a maze, an irradiation chamber, and a radiation source storage area, said building comprised of concrete, lead, or both concrete and lead, wherein the temperature of said loading-unloading area, maze, and irradiation chamber is from about −

25°

C. to about 25°

C.;

said building further comprising a multipiece roof plug permitting access to said irradiation chamber and radiation source storage area;

ii) a continuous track extending from said loading-unloading area through said maze and into said irradiation chamber, said continuous track having a level-changing portion, and comprised of at least one rail, said continuous track comprising either two, four, six or eight levels, said continuous track having an elongated helical portion;

iii) at least two carriers, each carrier comprising a slave tray and a wheel assembly, said wheel assembly engaged with said at least one rail and pivotally attached along one side of each carrier, each carrier extending substantially horizontally from said continuous track toward said radiation source;

iv) at least one drive mechanism capable of moving each of said at least two carriers along said continuous track from said loading-unloading area, through said maze, into said irradiation chamber, and travelling over said level-changing portion of track, thereby changing horizontal and vertical position of said carrier with respect to said radiation source within said irradiation chamber, exiting said irradiation chamber, and travelling through said maze to said loading-unloading area;

v) a pusher capable of transferring a product located upon said slave tray from a first carrier to a second carrier;

vi) an radiation source stored below said irradiation chamber within said source storage area, said source brought into a substantially horizontal position within said irradiation chamber using a source rack hoist and guide assembly, when positioned within said irradiation chamber said radiation source is located centrally, on a horizontal plane, within said elongated helical portion of said continuous track, and positioned with an equivalent number of levels of track lying above said radiation source, as levels of continuous track that lie below said radiation source;

said radiation source adopting a product-overlapping-source configuration with respect to said product, said radiation source selected from either cobalt 60 and cesium 137.

31. A product irradiator comprising;

a loading-unloading area and an irradiation chamber;

a conveying means;

a radiation source located within said irradiation chamber;

a carrier; and

, at least one drive mechanism capable of moving said carrier along said conveying means, wherein at least one dimension of said carrier is variable.

33. The product irradiator of claim 31 wherein said source is oriented horizontally within said irradiation chamber, and said at least one dimension is the height.

34. The product irradiator of claim 31 wherein said source is oriented vertically within said irradiation chamber, and said at least one dimension is the width.

35. The product irradiator of claim 31 wherein said conveying means is selected from an overhead track, a under-carrier track, or a combination thereof.

36. The product irradiator of claim 31 wherein said conveying means comprises more than one level.

37. The product irradiator of claim 36 wherein said conveying means includes a level-changing portion.

32. The product irradiator of claim 32, wherein said carrier comprises a wheel assembly that is adjustable in said at least one dimension.

38. A product irradiator comprising:

i) a loading-unloading area and an irradiation chamber;

ii) a continuous elongated helical track having a level-changing portion, said continuous track entering and exiting said irradiation chamber from said loading-unloading area, said continuous track comprised of at least one rail and of at least two levels;

iii) a radiation source located within said irradiation chamber;

iv) a substantially horizontal, cantilevered, carrier engaged to said at least one rail; and

v) at least one drive mechanism capable of moving said carrier along said continuous track.

39. A product irradiator comprising:

i) a loading-unloading area and an irradiation chamber;

ii) a continuous elongated helical track having a level-changing portion, said continuous track entering and exiting said irradiation chamber from said loading-unloading area, said continuous track comprised of at least one rail and of at least two levels within said irradiation chamber, said track oriented towards the perimeter of said irradiation chamber;

iii) a radiation source located within said irradiation chamber;

iv) a substantially horizontal, cantilevered, carrier engaged to said at least one rail; and

v) at least one drive mechanism capable of moving said carrier along said continuous track.