Environmental factor detection system for inkjet printing

• US 20030020773A1
• Filed: 04/30/2001
• Published: 01/30/2003
• Est. Priority Date: 04/30/2001
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Su, Wen-Li, Gudaitis, Algird M., Schantz, Christopher A.
• Granted Patent: US 6,568,780 B2
• Time in Patent Office: Days
• US Class Current: 347/14
• CPC Class Codes: B41J 2/125 Sensors, e.g. deflection sensors nozzle clogging detection for cleaning reasons B41J2/16579; detection for compensation for failed nozzles B41J2/2139
• CPC Class Codes: B41J 29/393 Devices for controlling or analysing the entire machine ; Controlling or analysing mechanical parameters involving printing of test patterns

Abstract

An environmental condition detection system for a hardcopy device, such as an inkjet printing mechanism, includes an environmental condition sensor having an optical property which changes in response to a change in an environmental condition, for instance humidity or temperature. The system also has an optical sensor which detects changes in the optical property and generates a signal for a controller that responds by changing an operating parameter of the hardcopy device. A hard copy device having such a environmental condition detection system is also provided, along with a method of determining an environmental condition within which a hardcopy device is operating.

Claims

1. An environmental condition detection system for a hardcopy device, comprising:

an environmental condition sensor having an optical property which changes in response to a change in an environmental condition; and

an optical sensor which detects said change in the optical property and generates a signal in response thereto.

2. An environmental condition detection system according to claim 1 wherein said environmental condition comprises temperature, and said environmental condition sensor comprises a temperature sensor.

3. An environmental condition detection system according to claim 2 wherein said optical property of the temperature sensor comprises one color which changes to another color in response to a selected change in temperature.

4. An environmental condition detection system according to claim 1 wherein said environmental condition comprises humidity, and said environmental condition sensor comprises a humidity sensor.

5. An environmental condition detection system according to claim 4 wherein said optical property of the humidity sensor comprises a first color which changes to a second color in response to a selected change in humidity.

6. An environmental condition detection system according to claim 5 wherein said selected change in humidity comprises a first humidity level.

7. An environmental condition detection system according to claim 6 wherein said optical property of the humidity sensor changes from said second color to a third color when the humidity is above said first humidity level.

8. An environmental condition detection system according to claim 7 wherein said first color comprises a blue color, said second color comprises a lavender color, and said third color comprises a pink color.

9. An environmental condition detection system according to claim 7 wherein said optical property of the humidity sensor changes from one color to another color in to a second selected change in humidity comprising a second humidity level.

10. An environmental condition detection system according to claim 1 wherein said optical property of the sensor comprises a first color-changing region which changes color in response to a first selected change in said environmental condition.

11. An environmental condition detection system according to claim 10 wherein said optical property of the sensor further comprises a second color-changing region which changes color in response to a second selected change in said environmental condition.

12. An environmental condition detection system according to claim 11 wherein said optical sensor moves between the first and second color-changing regions.

13. An environmental condition detection system according to claim 11 wherein the optical sensor remains stationary while detecting any color changes in the first and second color-changing regions.

14. An environmental condition detection system according to claim 1 further including a second environmental condition sensor having another optical property which changes in response to a change in another environmental condition, wherein the optical sensor detects said change in said another optical property and generates another signal in response thereto.

15. An environmental condition detection system according to claim 14 wherein:

said optical property of said environmental condition sensor comprises a color-changing region which changes color in response to said change in said environmental condition; and

said another optical property of said second environmental condition sensor comprises another color-changing region which changes color in response to said change in said another environmental condition.

16. An environmental condition detection system according to claim 15 wherein said optical sensor moves between said environmental condition sensor and said second environmental condition sensor.

17. An environmental condition detection system according to claim 1 wherein said environmental condition sensor comprises a base material treated with a solution of a color-changing material which changes color in response to said change in said environmental condition.

18. An environmental condition detection system according to claim 17 wherein said base material is of an absorbent material having a first region which has absorbed said solution having a first concentration of said color-changing material, and a second region which has absorbed said solution having a second concentration of said color-changing material, with said second concentration being different from said first concentration, and with said first region changing color in response to a first change in said environmental condition, and said second region changing color in response to a second change in said environmental condition different from said first change.

19. An environmental condition detection system according to claim 17 wherein said solution comprises a cobalt chloride and the hardcopy device comprises an inkjet printing mechanism.

20. A method of determining an environmental condition within which a hardcopy device is operating, comprising:

exposing a sensor to an environmental condition, with the sensor having an optical property which changes in response a change to said environmental condition;

optically observing said sensor; and

thereafter, generating a signal in response to said optical property of the sensor.

21. A method according to claim 20 wherein said optical property comprises color.

22. A method according to claim 21 further comprising changing said color in response said change comprising a selected change in said environmental condition.

23. A method according to claim 20 wherein said optical property changes in response to said environmental condition comprising temperature.

24. A method according to claim 23 wherein said optical property comprises color.

25. A method according to claim 20 wherein said optical property changes in response to said environmental condition comprising humidity.

26. A method according to claim 25 wherein said optical property comprises color.

27. A method according to claim 20 wherein:

said optical property comprises a first region which changes in response to a first change to said environmental condition, and a second region which changes in response to a second change to said environmental condition;

said exposing comprises exposing said first and second regions to said environmental condition; and

said optically observing comprises observing said first and second regions.

28. A method according to claim 27 wherein said optical property comprises color.

29. A method according to claim 20 wherein:

said exposing comprises exposing another sensor to another environmental condition, with said another sensor having another optical property which changes in response a change to said another environmental condition;

said optically observing comprises observing said another sensor; and

therereafter, generating another signal in response to said another optical property of said another sensor.

30. A method according to claim 29 wherein said optical property comprises color and said another property comprises another color.

31. A method according to claim 29 wherein said environmental condition comprises humidity, and said another environmental condition comprises temperature.

32. A method according to claim 29 wherein said optically observing comprises using optical sensor to observe said sensor and said another sensor, and moving said optical sensor between said sensor and said another sensor.

33. A method according to claim 20 wherein said hardcopy device comprises an inkjet printing mechanism.

34. A method according to claim 20 wherein said optically observing comprises using an optical sensor to observe said sensor, and holding said optical sensor stationary while observing said sensor.

35. A method of operating a hardcopy device, comprising:

exposing a sensor to an environmental condition within which said hardcopy device is operating, with the sensor having an optical property which changes in response a change to said environmental condition;

optically observing said sensor;

thereafter, generating a signal in response to said optical property of the sensor; and

adjusting an operating parameter of said hardcopy device in response to said signal.

36. A method according to claim 35 wherein said hardcopy device comprises an inkjet printing mechanism for printing on a sheet having opposing first and second surfaces, and the method further comprises:

printing on said first surface of the sheet;

thereafter, reversing said sheet;

thereafter, printing on said second surface of the sheet; and

between said printing on the first surface and printing on the second surface, drying the sheet for a selected dry time delay;

wherein said adjusting comprises adjusting the selected dry time delay.

37. A method according to claim 36 wherein said environmental condition comprises temperature.

38. A method according to claim 36 wherein said environmental condition comprises humidity, and said adjusting comprises reducing the selected dry time delay under dry humidity conditions.

39. A method according to claim 35 wherein said hardcopy device comprises an inkjet printing mechanism for printing on first and second sheets, and the method further comprises:

printing on said first sheet;

thereafter, drying the first sheet for a selected dry time delay; and

thereafter, printing on said second sheet;

wherein said adjusting comprises adjusting the selected dry time delay.

40. A method according to claim 39 wherein said environmental condition comprises humidity, and said adjusting comprises reducing the selected dry time delay under dry humidity conditions.

41. A method according to claim 35 wherein said hardcopy device comprises an inkjet printing mechanism having a printhead which selectively dispenses ink, and the method further comprises:

collecting a history of said environmental condition during a period of printhead inactivity; and

analyzing said history;

wherein said adjusting comprises adjusting a printhead servicing routine in response to said analyzing.

42. A method according to claim 41 wherein said environmental condition comprises humidity, said servicing routine comprises purging a selected amount of ink from the printhead, and said adjusting comprises reducing the selected amount of ink purged during said servicing under high humidity conditions.

43. A method according to claim 35 wherein said hardcopy device comprises an inkjet printing mechanism having a printhead, and the method further comprises:

selectively dispensing ink from the printhead according to a printing routine;

collecting a history of said environmental condition during printhead inactivity; and

analyzing said history to estimate an amount of ink evaporated from said printhead during said period of inactivity.

44. A method according to claim 43 further comprising:

compiling the amount of ink dispensed from the printhead from when the printhead was initially installed in the printing mechanism; and

estimating the amount in ink remaining in an ink supply coupled to the printhead in response to said analyzing and said compiling.

45. A method according to claim 44 further comprising:

predicting an upcoming out of ink condition from said estimating; and

alerting an operator of said upcoming out of ink condition.

46. A method according to claim 43 wherein said adjusting comprises adjusting the printing routine in response to said analyzing.

47. A method according to claim 46 wherein:

said analyzing comprises determining an amount of ink volatiles evaporated from said printhead during said period of inactivity;

wherein said adjusting comprises adjusting the printing routine to compensate for said evaporated volatiles.

48. A method according to claim 35 wherein said hardcopy device comprises an inkjet printing mechanism having a printhead, and the method further comprises:

advancing media through a printzone of the printing mechanism; and

selectively dispensing ink from the printhead onto the media while in the printzone;

wherein said adjusting comprises adjusting the advancing step.

49. A method according to claim 48 wherein said environmental condition comprises humidity.

50. A hardcopy device for interacting with media, comprising:

an interaction head which interacts with said media when in an interaction zone;

a media handling system which advances the media through the interaction zone;

an environmental condition sensor having an optical property which changes in response to a change in an environmental condition within which the hardcopy device operates;

an optical sensor which detects said change in the optical property and generates a signal in response thereto; and

a controller which adjusts an operating parameter of said hardcopy device in response to said signal.

51. A hardcopy device according to claim 50 wherein said environmental condition comprises temperature, and said environmental condition sensor comprises a temperature sensor.

52. A hardcopy device according to claim 51 wherein said optical property of the temperature sensor comprises one color which changes to another color in response to a selected change in temperature.

53. A hardcopy device according to claim 50 wherein said environmental condition comprises humidity, and said environmental condition sensor comprises a humidity sensor.

54. A hardcopy device according to claim 53 wherein said optical property of the humidity sensor comprises a first color which changes to a second color in response to a selected change in humidity.

55. A hardcopy device according to claim 54 wherein:

said selected change in humidity comprises a first humidity level; and

said optical property of the humidity sensor changes from said second color to a third color when the humidity is above said first humidity level.

56. A hardcopy device according to claim 55 wherein said first color comprises a blue color, said second color comprises a lavender color, and said third color comprises a pink color.

57. A hardcopy device according to claim 50 wherein said optical property of the sensor comprises a first color-changing region which changes color in response to a first selected change in said environmental condition.

58. A hardcopy device according to claim 57 wherein said optical property of the sensor further comprises a second color-changing region which changes color in response to a second selected change in said environmental condition.

59. A hardcopy device according to claim 58 wherein:

interaction head reciprocates across the interaction zone; and

optical sensor moves with the interaction head to transport the optical sensor between the first and second color-changing regions.

60. A hardcopy device according to claim 58 wherein the optical sensor remains stationary while detecting any color changes in the first and second color-changing regions.

61. A hardcopy device according to claim 50 further including a second environmental condition sensor having another optical property which changes in response to a change in another environmental condition, wherein the optical sensor detects said change in said another optical property and generates another signal in response thereto.

62. A hardcopy device according to claim 61 wherein:

said optical property of said environmental condition sensor comprises a color-changing region which changes color in response to said change in said environmental condition; and

said another optical property of said second environmental condition sensor comprises another color-changing region which changes color in response to said change in said another environmental condition.

63. A hardcopy device according to claim 62 wherein:

the interaction head reciprocates across the interaction zone; and

the optical sensor moves with the interaction head to transport the optical sensor between said environmental condition sensor and said second environmental condition sensor.

64. A hardcopy device according to claim 50 wherein said environmental condition sensor comprises a base material treated with a solution of cobalt chloride.

65. A hardcopy device according to claim 50 wherein:

said hardcopy device comprises an inkjet printing mechanism for printing on a sheet;

said interaction head comprises a printhead; and

said interaction zone comprises a printzone.

66. A hardcopy device according to claim 65 wherein:

said sheet has opposing first and second surfaces;

hardcopy device further comprises a duplexing mechanism which receives said sheet after printing on said first surface, reverses said sheet from said first surface to said second surface, then delivers said sheet back to the printzone for printing on said second surface after delaying for a selected dry time delay;

said environmental condition comprises humidity; and

the controller adjusts said operating property comprising said selected dry time delay in response to the humidity.

67. A hardcopy device according to claim 65 wherein:

said sheet comprises a first sheet, and the printing mechanism prints on a second sheet in plural sheet print job; and

said controller adjusts said operating parameter comprising a selected dry time delay between printing on said first sheet and said second sheet.

68. A hardcopy device according to claim 67 wherein said environmental condition comprises humidity.

69. A hardcopy device according to claim 68 wherein said controller increases said selected dry time delay when the humidity is at a high level.

70. A hardcopy device according to claim 65 wherein:

said printhead selectively dispenses ink;

said controller collects a history of said environmental condition during a period of printhead inactivity and analyzes said history; and

said controller adjusts said operating parameter comprising a servicing routine which services the printhead.

71. A hardcopy device according to claim 70 wherein:

said environmental condition comprises humidity and temperature; and

the servicing routine purges a selected amount of ink from the printhead, and the controller adjusts the selected amount of ink purged in accordance with the humidity and temperature.

72. A hardcopy device according to claim 65 wherein:

the printhead selectively dispenses ink from an ink supply while printing according to a printing routine; and

the controller compiles a history of said environmental condition during printhead inactivity, analyzes the history to estimate an amount of ink evaporated from the printhead, compiles an amount of ink dispensed from the printhead from when the printhead was initially installed in the printing mechanism, and estimates an amount of ink remaining in the ink supply.

73. A hardcopy device according to claim 72 further wherein the controller predicts an upcoming out of ink condition from the estimate of the amount of ink remaining in the ink supply, and alerts an operator of said upcoming out of ink condition.

74. A hardcopy device according to claim 72 wherein the controller adjusts the printing routine in response to the estimate of the amount of ink remaining in the ink supply.

75. A hardcopy device according to claim 72 wherein the controller determines an amount of ink volatiles evaporated from said printhead during inactivity, and adjusts the printing routine to compensate for the evaporated ink volatiles.

76. A hardcopy device according to claim 65 wherein the media handling system advances the media through the interaction zone according to a media advancing routine, and the controller adjusts the media advancing routine in response to an environmental condition comprising humidity.

77. A hardcopy device according to claim 50 wherein said environmental condition sensor comprises a base material carrying a cholesteric liquid crystal material, and said environmental condition comprises temperature.