Compensating for variations in article speeds and characteristics at different article positions during article irradiation

• US 20040217300A1
• Filed: 05/02/2003
• Published: 11/04/2004
• Est. Priority Date: 05/02/2003
• Status: Active Grant

• Current Assignee: L-3 Services Incorporated (L3Harris Technologies, Inc.)
• Original Assignee: Titan (L3Harris Technologies, Inc.)
• Inventors: Loda, Gary K.
• Granted Patent: US 6,919,572 B2
• Time in Patent Office: Days
• US Class Current: 250/492.1
• CPC Class Codes: G21K 5/10 with provision for relative movement of beam source and object to be irradiated

Abstract

First embodiment: an article is conveyed in a first direction at different speeds at different positions on the article in a second direction substantially perpendicular to the first direction. For example, when the article is conveyed in a rotary direction, the positions on the radially outer side of the article rotate at higher speeds than the positions at the radially inner side of the article. Radiant energy directed against the conveyed article is scanned on a cyclic basis in the second direction between the radially inner and outer sides of the article. During the scanning, the intensity of the radiant energy is varied at each position in the second direction to direct a constant intensity of radiant energy against the article at every position in the article. Second embodiment: the article scanning in the second direction is varied according to the article characteristics (e.g. thickness) in the second direction.

Claims

1. In combination for applying radiant energy to articles,

a ring-shaped carousel disposed in a closed loop defined by an inner dimension and an outer dimension greater than the inner dimension and movable in the closed loop,

a motor for rotating the ring-shaped carousel in the closed loop,

an accelerator for directing radiant energy to the articles in the carousel,

a first member disposed within the ring-shaped carousel and having a diameter less than the inner diameter and made from a material providing a shielding against the radiant energy from the accelerator,

a second member enveloping the ring-shaped carousel and having a diameter greater than the inner diameter of the carousel and providing a shielding against the radiant energy from the carousel, and

an electronic system for compensating in the intensity of the radiant energy from the accelerator for the differences in the speed of the carousel at individual positions between the inner and outer dimensions of the carousel.

2. In a combination as set forth in claim 1,

the accelerator being operative to provide successive scans of radiant energy between the inner and outer dimensions and to offset the difference in the speed of the articles at the individual positions between the inner and outer dimensions of the carousel in accordance with the differences in the intensity of the radiation at the individual positions.

3. In a combination as set forth in claim 1,

the carousel having a cylindrical configuration and the inner and outer dimensions respectively constituting inner and outer diameters.

4. In a combination as set forth in claim 1,

the scan of the radiant energy beam being advanced in position between the inner and outer dimensions on the basis of a digital count and the positions of each digital count between the inner and outer dimensions being offset by a particular amount from the preceding and following digital counts between the inner and outer dimensions.

5. In a combination as set forth wherein

a look-up table is responsive to each digital count for providing an intensity of the radiant energy individual to that digital count to compensate in the intensity of the radiant energy for the differences in the speed of the carousel at the individual positions between the inner and outer dimensions of the carousel.

8. In a combination as set forth in claim 5 wherein

the conveyor moves the articles in a first direction past the radiant energy from the accelerator and wherein

the radiant energy is scanned in a second direction transverse to the first direction on a cyclic basis and wherein

the movement of the conveyor at the different speeds is at the individual positions in the second direction and wherein

the electronic system adjusts the intensity of the radiant energy at the individual positions in the second direction in accordance with the different speeds of the articles at the individual positions in the second direction.

6. In a combination for applying radiant energy to articles,

an accelerator for providing radiant energy,

a conveyor for moving individual positions on the article at different speeds past the radiant energy from the accelerator, and

an electronic system for adjusting the intensity of the radiant energy from the accelerator at the individual positions on the articles, during the movement of the articles past the accelerator, in accordance with the different speeds of movement of the individual positions on the articles past the accelerator.

7. In a combination as set forth in claim 6 wherein

the adjustment in the intensity of the radiant energy from the accelerator at each individual position on the articles is in inverse relationship to the differences in the speed of movement of the articles at that position past the radiant energy from the accelerator relative to the speed of movement of other positions on the articles past the radiant energy.

9. In a combination as set forth in claim 7 wherein

the adjustment in the intensity of the radiant energy from the accelerator at each individual position in the second direction is in inverse relationship to the difference in the speed of movement of the articles at that position past the radiant energy from the accelerator relative to the speed of movement of the articles at other positions in the second direction.

10. In a combination as set forth in claim 9 wherein

the adjustment in the intensity of the radiant energy from the accelerator at each position in the second direction is on a cyclic basis at a particular frequency.

11. In a combination for applying radiant energy to articles,

an accelerator for providing radiant energy,

a conveyor for moving the articles in a first direction past the radiant energy from the accelerator at different speeds at different positions in a second direction transverse to the first direction,

a system for scanning the radiant energy in the second direction on a recurrent basis,

electrical circuitry for providing an offset in the scanning of the radiant energy in the second direction in alternate recurrent scans, and

electrical circuitry for varying the intensity of the radiant energy from the offset at the different positions in the second direction in the alternate recurrent scans in the second direction in accordance with the differences in the speed of movement of the articles in the first direction at the different positions in the second direction.

12. In a combination as set forth in claim 11,

first electrical circuitry for alternately providing the offset intensity of the radiant energy in positive and negative polarities from an intermediate intensity at progressive positions in the second direction in alternate recurrent scans, and

electrical circuitry for alternately providing progressive intensities of radiation in the positive and negative polarities from the offset intensity of radiant energy at progressive positions in the second direction in the alternate recurrent scans.

13. In a combination as set forth in claim 11 wherein

the first direction is annular and the second direction is in the same plane as the first direction and is substantially perpendicular to the first direction and the radiant energy from the accelerator is substantially perpendicular to this plane.

14. In a combination for applying radiant energy to articles,

a conveyor for moving the articles at different speeds in a first direction, the different speeds occurring in the first direction for different positions of the articles in a second direction transverse to the first direction,

an accelerator for applying radiant energy to the articles in a third direction transverse to the first and second directions, and

a regulator for varying the intensity of the excitation of the accelerator at individual positions in the second direction in accordance with the differences in the speed of movement of the articles in the first direction at the different positions in the second direction.

15. In a combination as set forth in claim 14 wherein

the second direction is substantially perpendicular to the first direction and the third direction is substantially perpendicular to the first and second directions.

16. In a combination as set forth in claim 14 wherein

the regulator changes the intensity of the radiant energy at the individual positions in the second direction to compensate for the differences in the speed of movement of the articles in the first direction at the different positions in the second direction.

17. In a combination as set forth in claim 14 wherein

the first direction is annular and the second direction defines a plane with the first direction and the third direction is substantially perpendicular to the plane defined by the first and second directions.

18. In a combination as set forth in claim 14 wherein

the radiation is in the form of a beam and wherein

the radiation beam is scanned in the second direction on a cyclical basis as the conveyor moves the articles in the first direction.

19. In a combination as set forth in claim 15 wherein

the regulator changes the intensity of the radiant energy at the individual positions in the second direction to compensate for differences in the speed of movement of the articles in the first direction at the individual positions in the second direction and wherein

the radiation is in the form of a beam and wherein

the radiation beam is scanned in the second direction on a cyclical basis as the conveyor moves the articles in the first direction.

20. In a combination as set forth in claim 14 wherein

the radiation is in the form of a beam and wherein

the radiation beam is scanned in the second direction on a cyclical basis as the conveyor moves the articles in the first direction.

21. In a combination as set forth in claim 20 wherein

an offset is provided in alternate scans in the second direction.

22. In a combination as set forth in claim 14 wherein

the scan in the second direction is on a digital basis and wherein

a look-up table is responsive to the scan on the digital basis in the second direction for providing an individual intensity in the radiant energy for each digital position in the scan of the radiant energy in the second direction to compensate for differences in the speed of movement of the articles in the first direction at that digital position in the second direction.

23. In combination for applying radiant energy to articles,

a conveyor for providing a movement of the articles at different speeds in a first direction, the different speeds occurring in the first direction for different positions of the articles in a second direction transverse to the first direction,

an accelerator for applying radiant energy to the articles in a third direction transverse to the first and second directions,

electrical circuitry for scanning the articles in the second direction on a cyclical basis as the conveyor moves the articles in the first direction, and

a regulator for varying the intensity of the radiant energy at individual positions of the articles in each cyclical scan of the radiant energy in the second direction in accordance with the different speeds of movement of the articles in the first direction at the individual positions of the articles in the second direction.

24. In a combination as set forth in claim 23 wherein

an offset is provided, in alternate ones of the scans in the second direction relative to the other ones of the scans in the second direction, in the intensity of the radiant energy at the successive positions of the articles in the second direction.

25. In a combination as set forth in claim 24 wherein

a positive offset voltage of a particular magnitude is produced at the beginning of a first portion of each cyclic scan in the second direction and wherein the magnitude of the voltage is increased in the positive direction from the positive offset voltage during the remainder of the first portion of each scan and wherein

a negative offset voltage of the particular magnitude is produced at the beginning of a second portion of each cyclic scan in the second direction and wherein the magnitude of the voltage is increased in the negative direction from the negative offset voltage during the remainder of the second portion of each scan.

26. In a combination as set forth in claim 24 wherein

the regulator operates on a digital basis and wherein

the offset is provided in the alternate scans to enhance the production of a substantially uniform intensity of the radiant energy at every position in the article in the second direction.

27. In a combination as set forth in claim 26 wherein

a lookup table is responsive to the operation of the regulator on the digital basis for providing a correction in the intensity of the radiant energy for each digital change in the operation of the regulator to compensate for the difference in the speed of movement of the articles in the first direction at the individual positions in the second direction.

28. In a combination for radiating an article,

a source of clock signals,

a first counter for counting the clock signals to a particular value,

a second counter for the clock signals to the particular value,

a toggle arrangement for alternately energizing the first and second counters,

a source of an offset voltage,

an adder for adding the offset voltage to the voltage from the second counter,

an accelerator for providing radiant energy for irradiating the article,

a conveyor for moving the article in a first direction past the radiant energy from the accelerator,

a lookup table responsive at each instant to the voltage from the first counter to provide at that instant an output for obtaining an irradiation of the article with an intensity dependent upon the output from the lookup table at that instant,

the lookup table being responsive at each instant to the voltage from the adder to provide at that instant an output for obtaining an irradiation of the article with an intensity dependent upon the output from the lookup table at that instant, and

a scan magnet in the accelerator, the scan magnet being responsive at each instant to the output from the energized one of the first counter and the adder to direct the radiant energy from the source at that instant to a particular position on the article in a second direction transverse to the first direction.

29. In a combination as set forth in claim 28,

the accelerator providing the radiation in a second direction transverse to the first direction,

the lookup table providing for variations in the intensity of the radiation from the accelerator to compensate for the difference in the speed of the article in the first direction at the different positions in the second direction.

30. In a combination as set forth in claim 28 wherein

the conveyor constitutes a carousel movable in a looped path and the different positions on the articles on the carousel move at different speeds dependent upon the disposition of the different positions relative to the outside of the loop and the inside of the loop and wherein

the lookup table provides an output at each position in the second direction to compensate for differences in the speed of movement of the articles in the first direction at that position.

31. In a combination as set forth in claim 29 wherein

the first, second and third directions are substantially perpendicular to one another and wherein the carousel is a ring-shaped cylinder having a particular axis and a particular diameter and wherein the carousel rotates on the particular axis as a fulcrum.

32. In a combination for irradiating articles,

a source of clock signals,

a counter for counting the clock signals to a particular value on a cyclic basis,

an accelerator for providing radiant energy in a first direction for irradiating the articles,

a conveyor for moving the articles past the radiant energy in a second direction transverse to the first direction,

a lookup table responsive at each instant to the count from the counter for providing at that instant an irradiation of the article with an intensity dependent upon the count from the counter at that instant, and

a scan magnet responsive in the accelerator at each instant to the output from the counter to direct the radiant energy from the source at that instant to a particular position on the article in a third direction transverse to the first and second directions.

33. In a combination as set forth in claim 32,

the conveyor providing a movement of the article in a loop having a particular radius, and

the lookup table being operative to compensate in the intensity of the radiation from the source to the movement of different positions of the article dependent upon the radius of those positions in the loop.

34. In a combination as set forth in claim 32 wherein

the first, second and third directions are substantially perpendicular to one another and wherein

the article is movable in a circular path defined by an axis of rotation.

35. In a combination as set forth in claim 32 wherein

an offset is provided in the count from the counter to the particular value in alternate cycles and wherein

the lookup table is responsive at each instant to the offset in the count from the counter in the alternate cycles for providing an irradiation of the article with an intensity dependent upon the offset in the count from the counter at that instant.

36. In combination for applying radiant energy to articles having different characteristics at individual positions in a first direction,

an accelerator for providing radiant energy in a second direction substantially perpendicular to the first direction,

a conveyor for moving the articles past the radiant energy from the accelerator in a third direction substantially perpendicular to the first and second directions,

a scanner for scanning the articles on the conveyor at the first direction on a cyclic basis, and

an electronic system for adjusting the intensity of the radiant energy from the accelerator at individual positions on the articles in the first direction, during the movement of the articles in the third direction on the conveyor and the scanning of the articles in the first direction, in accordance with the different characteristics of the articles at the individual positions in the first direction.

37. In a combination as set forth in claim 36 wherein

the differences in the characteristics of the articles at the individual positions in the first direction constitute differences in the thickness of the articles at the individual positions in the first direction.

38. In a combination as set forth in claim 36 wherein

the electronic system includes a source of clock signals and a counter for counting the clock signals to a particular count on the cyclic basis and a lookup table for providing a voltage, at each count to the particular value, for introduction to the accelerator to produce an intensity of the radiant energy at individual positions in the first direction for compensating for the differences in the characteristics of the articles at the individual positions in the first direction.

39. In a combination as set forth in claim 38 wherein

the articles have variations in thickness at individual positions in the first direction and wherein

the adjustment in the intensity of the radiant energy at each individual position of the articles in the first direction on the cyclic basis corresponds to variations in the thickness of the articles at the individual positions in the first direction.

40. In a combination as set forth in claim 36 wherein

the article has first and second opposite sides and wherein

the scanner constitutes a first scanner for scanning a first side of the articles and wherein

a second scanner is provided for scanning a second side of the article opposite to the first side and wherein

the electronic system adjusts the intensity of the radiant energy from the accelerator at individual positions on the opposite sides of the articles in the first direction, during the movement of the articles in the third direction on the conveyor and the scanning of the articles in the first direction in accordance with the different characteristics of the articles at the individual positions in the first direction.

41. In a combination for applying radiant energy to articles having different characteristics at individual positions in a first direction,

an accelerator for providing radiant energy to the articles in a second direction transverse to the first direction,

a conveyor for moving the articles past the radiant energy from the accelerator in a third direction transverse to the first and second directions,

a scanner for scanning the radiant energy in the second direction on a recurrent basis,

first electrical circuitry for providing an offset in the scanning of the radiant energy in the first direction in alternate recurrences, and

second electrical circuitry for varying the intensity of the radiant energy from the accelerator in the scanning of the radiant energy in the first direction at individual positions in the first direction to compensate for the different characteristics of the articles at the individual positions in the first direction.

42. In a combination as set forth in claim 41 wherein

the second electrical circuitry provides in alternate recurrences for the scanning of the radiant energy in the first direction with an offset and provides for variations in the intensity of the radiant energy at each instant in the other recurrences in accordance with the position of the radiant energy at that instant in the first direction and provides for variations in the intensity of the radiant energy at each instant in the alternate recurrences in accordance with the offset position of the radiant energy at that instant in the first direction.

43. In a combination as set forth in claim 42 wherein

a counter provides for a count on a digital basis to a particular value in the alternate recurrences and the other recurrences and wherein the offset is added to the digital count in the alternate recurrences and wherein a lookup table provides for a radiation intensity at each instant in the other recurrences in accordance with the count in the counter at that instant in the alternate recurrences and provides for a radiation intensity at each instant in the alternate recurrences in accordance with the count in the counter, added to the offset, at that instant in the alternate recurrences and wherein

the counter and the lookup table are included in the second electrical circuitry.

44. A method of applying radiant energy to articles, including the steps of:

conveying the articles in a first direction at different speeds at individual positions in a second direction substantially perpendicular to the first direction,

directing radiant energy against the articles in a third direction substantially perpendicular to the first and second directions,

scanning the radiant energy directed against the articles on a cyclic basis in the second direction, and

compensating in the scan intensity of the radiant energy in the second direction on the cyclic basis for the differences in the speed of movement in the first direction of the articles at the individual positions in the second direction.

45. A method as set forth in claim 44 wherein

the step of compensating comprises varying the intensity of the radiation at the individual positions in the second direction in accordance with the differences in the speed of movement of the articles in the first direction at the individual positions of the articles in the second direction.

46. In a method as set forth in claim 45 wherein

the speed of movement of the articles on the conveyor is incremental in the first direction at the successive incremental positions in the second direction and wherein

the intensity of the radiation is varied at the successive incremental positions of the articles in the second direction in accordance with the increments in the speed of movement of the articles in the first direction at the successive incremental positions of the articles in the second direction.

47. In a combination as set forth in claim 45 wherein

the intensity of the radiation is incremented at the successive incremental positions of the articles in the second direction to provide a substantially constant intensity of radiation of the articles in the first direction at the successive incremental positions of the scan in the second direction.

48. In a method as set forth in claim 45 wherein

the first direction is annular thereby causing the speed of movement of the articles in the annular direction to increase substantially linearly with successive positions of the articles in the second direction and wherein

the intensity of the radiation is varied at the incremental positions of the articles in the second direction to compensate for the differences in the speed of the articles in the first direction at the successive positions of the articles in the second direction.

49. A method of applying radiant energy to articles, including the steps of:

providing radiant energy in a first direction,

conveying the articles past the radiant energy in a second direction transverse to the first direction, the conveyance in the second direction being at different speeds at incremental positions of the articles in a third direction transverse to the first and second directions,

scanning the radiant energy on a cyclical basis in the third direction,

varying the intensity of the radiant energy in the incremental positions of the articles in the third direction to compensate for the differences in the speed of conveyance of the articles in the second direction at the different positions of the articles in the third direction, and

offsetting the scanning of the radiant energy in the third direction in alternate cycles relative to the scanning of the radiant energy in the third direction in the other cycles.

50. A method as set forth in claim 49 wherein

the scanning of the radiant energy in the third direction is incremental and wherein

the variation in the intensity of the radiant energy in the incremental positions of the articles in the third direction is incremental to compensate for the differences in the speed of conveyance of the articles in the second direction at the incremental positions of the articles in the third direction.

51. A method as set forth in claim 49 wherein

the first, second and third directions are substantially perpendicular to one another and wherein the second direction is in a loop defined by a particular axis, thereby producing linear increases in the speed of movement of the article at progressive increases in the diameter of the loop and wherein

the intensity of the radiation is linearly increased at linear increases in the radius of the loop.

52. A method as set forth in claim 49 wherein

the conveyor is in the form of a cylindrical carousel having a ring-shaped configuration and wherein

first radiation shielding material is disposed within the ring configuration and second radiation shielding material is disposed outside of the ring configuration.

53. A method as set forth in claim 49 wherein

an offset is provided in alternate cycles in the scanning of the articles in the third direction and wherein

compensation is provided, in the third direction in the alternate cycles, in the intensity of the radiant energy for the offset in the scanning of the articles.

54. In a method of applying radiant energy to articles having different characteristics at individual positions in a first direction, the steps of:

providing an irradiation of the articles in a second direction transverse to the first direction,

conveying the articles past the irradiation in a third direction transverse to the first and second directions,

scanning the articles in the first direction on a recurrent basis, and

varying the intensity of the irradiation of the articles, during the scanning of the articles in the first direction on the recurrent basis, to compensate for differences in the characteristics of the articles at the individual positions in the first direction.

55. A method as set forth in claim 54 wherein

the articles are scanned in the first direction on the recurrent basis from the opposite sides of the articles and wherein

the intensity of the irradiation of the articles is varied, during the scanning of the articles in the first direction from the opposite sides of the articles on the recurrent basis, to compensate for differences in the characteristics of the articles at the individual positions in the first direction.

56. A method as set forth in claim 54 wherein

an offset is provided in alternate scans of the articles in the first direction on the recurrent basis.

57. A method as set forth in claim 54 wherein

the differences in the characteristics of the articles at the individual positions of the articles in the first direction constitute differences in the thickness of the articles at the individual positions of the articles in the first direction.

58. A method as set forth in claim 56 wherein

the differences in the characteristics of the articles at the individual positions of the articles in the first direction constitute differences in the thickness of the articles at the individual positions of the articles in the first direction.

59. A method as set forth in claim 54 wherein

the scanning of the articles on the recurrent basis in the first direction is electronic.

60. A method as set forth in claim 55 wherein

the scanning of the articles on the recurrent basis in the first direction is electronic.

61. A method as set forth in claim 56 wherein

the scanning of the articles on the recurrent basis in the first direction is electronic.