Ink supply mechanism for a dot matrix printer

• US 5,421,658 A
• Filed: 11/10/1993
• Issued: 06/06/1995
• Est. Priority Date: 05/22/1984
• Status: Expired due to Term

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Suzuki, Takashi, Miyazawa, Yoshinori, Matsuzawa, Masanao
• Primary Examiner(s): WIECKING, DAVID
• Application Number:
  US08/150,676
• Time in Patent Office: 573 Days
• Field of Search: 400/124, 400/124 GT, 400/124 IW, 400/470, 400/471, 400/471.1, 400/124.10, 346/140 R, 346/140 PD, 101/97, 101/98, 101/333, 101/335, 101/364, 347/86, 347/92, 347/93, 347/94, 347/85
• US Class Current: 400/124.1
• CPC Class Codes: B41J 2/17503 Ink cartridges
• CPC Class Codes: B41J 2/17513 Inner structure
• CPC Class Codes: B41J 2/255 Arrangement of the print ends of the wires
• CPC Class Codes: B41J 2/305 Ink supply apparatus ink ribbons, ink-ribbon mechanisms B41J31/00 - B41J35/00

Abstract

An ink-supplied wire dot matrix printer head for actuating wires with ink attached to tip ends thereof into contact with a sheet of print paper to transfer ink to the sheet, thereby forming ink dots thereon. The ink-supplied wire dot matrix printer head includes a wire guide member having a wire guide hole for guiding the tip end of the wire, and an ink tank containing an ink absorbing body therein and having an ink supply port in which a portion of the wire guide member is inserted. The wire guide member has a capillary ink path communicating with a side of the wire and supplied with ink from the ink absorbing body.

Claims

1. A dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank;

a printing mechanism for applying ink from the ink absorbing member to effect printing; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink to said printing means through said first wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wall essentially defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink from said opening toward said printing mechanism by at least capillary force, said passage being essentially free of porous material, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening.

2. The dot matrix printer of claim 1, said elongated member occupying substantially less than the entire area of said first wall.

3. The dot matrix printer of claim 2, said elongated member occupying only a minor portion of the entire area of said first wall.

4. The dot matrix printer of claim 1, wherein the ink absorbing member is formed of a unitary piece of porous material.

5. The dot matrix printer of claim 4, wherein the unitary piece of porous material substantially fills the ink-supply tank.

6. The dot matrix printer of claim 4, wherein the unitary piece of porous material carries substantially all of the ink that said ink-supply tank was designed to hold.

7. The dot matrix printer of claim 1, wherein the ink absorbing member is formed of at least two pieces of porous material, each of said pieces of porous material abutting another of said pieces of porous material along respective surfaces thereof for the transfer of ink therebetween.

8. The dot matrix printer of claim 7, wherein said ink absorbing member substantially fills the ink-supply tank.

9. The dot matrix printer of claim 7, wherein the said ink absorbing member carries substantially all of the ink that said ink-supply tank was designed to hold.

10. The dot matrix printer of claim 7, wherein at least two of said pieces of porous material are of different average pore size, the average pore size of the piece of porous material compressed by said elongated member being of the smallest of the average pore sizes of the pieces of porous material.

11. The dot matrix printer of claim 1, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

12. The dot matrix printer of claim 11, wherein said first wall of said ink-supply tank essentially defines one side of said ink-supply tank.

13. The dot matrix printer of claim 1, wherein said ink-supply tank includes a further wall facing the end of said elongated member, said ink absorbing member being compressingly contained in the space intermediate said further wall and said elongated member.

14. The dot matrix printer of claim 13, wherein said wall of said ink-supply tank facing said elongated member is a cover means bearing on said ink absorbing member when assembled to said ink-supply tank to at least in part apply a compressive force to effect compression of said ink absorbing member.

15. The dot matrix printer of claim 13, and including ink impregnated in the ink absorbing member under a pressure sufficiently low to substantially eliminate air bubbles in the ink absorbing member.

16. The dot matrix printer of claim 13, and including means for providing ambient air to the space between said ink absorbing member and a wall of said ink-supply tank.

17. The dot matrix printer of claim 13, wherein said ink absorbing member carries substantially all of the ink in said ink-supply tank when said ink-supply tank is filled to the designed capacity of the ink-supply tank, said ink-supply tank including an inner wall surface having projections to provide a space between said ink absorbing member and said wall surface.

18. The dot matrix printer of claim 17, wherein said further wall of said ink-supply tank facing said elongated member is a cover bearing on said ink absorbing member when assembled to said ink-supply tank to at least in part apply a compressive force to effect compression of said ink absorbing member, at least a portion of said projections extending from the inner wall surface of said cover.

19. An ink-supply system for a dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink from said ink-supply tank through said wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wall defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink away from said opening by at least capillary force, said passage being essentially free of porous material, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening.

20. The ink-supply system of claim 19, said elongated member occupying substantially less than the entire area of said first wall.

21. The ink-supply system of claim 20, said elongated member occupying only a minor portion of the entire area of said first wall.

22. The ink-supply system of claim 19, wherein the ink absorbing member is formed of a unitary piece of porous material.

23. The ink-supply system of claim 22, wherein the unitary piece of porous material substantially fills the ink-supply tank.

24. The ink-supply system of claim 22, wherein the unitary piece of porous material carries substantially all of the ink that said ink-supply tank was designed to hold.

25. The ink-supply system of claim 19, wherein the ink absorbing member is formed of at least two pieces of porous material, each of said pieces of porous material abutting another of said pieces of porous material along respective surfaces thereof for the transfer of ink therebetween.

26. The ink-supply system of claim 25, wherein said ink absorbing member substantially fills the ink-supply tank.

27. The ink-supply system of claim 25, wherein at least two of said pieces of porous material are of different average pore size, the average pore size of the piece of porous material compressed by said elongated member being of the smallest of the average pore sizes of the pieces of porous material.

28. The ink-supply system of claim 25, wherein the said ink absorbing member carries substantially all of the ink that said ink-supply tank was designed to hold.

29. The ink-supply system of claim 28, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

30. The ink-supply system of claim 29, wherein said first wall of said ink-supply tank essentially defines one side of said ink-supply tank.

31. The ink-supply system of claim 19, wherein said ink-supply tank includes a further wall facing the end of said elongated member, said ink absorbing member being compressingly contained in the space intermediate said further wall and said ink elongated member.

32. The ink-supply system of claim 31, wherein said wall of said ink-supply tank facing said elongated member is a cover means bearing on said ink absorbing member when assembled to said ink-supply tank to at least in part apply a compressive force to effect compression of said ink absorbing member.

33. The ink-supply system of claim 31, and including ink impregnated in the ink absorbing member under a pressure sufficiently low to substantially eliminate air bubbles in the ink absorbing member.

34. The ink-supply system of claim 31, and including means for providing ambient air to the space between said ink absorbing member and a wall of said ink-supply tank.

35. The ink-supply system of claim 31, wherein said ink absorbing member carries substantially all of the ink in said ink-supply tank when said ink-supply tank is filled to the designed capacity of the ink-supply tank, said ink-supply tank including an inner wall surface having projections to provide a space between said ink absorbing member and said wall surface.

36. The ink-supply system of claim 35, wherein said further wall of said ink-supply tank facing said elongated member is a cover bearing on said ink absorbing member when assembled to said ink-supply tank to at least in part apply a compressive force to effect compression of said ink absorbing member, at least a portion of said projections extending from the inner wall surface of said cover.

37. A method for supplying ink for a dot matrix printer comprising:

providing an ink absorbing member formed of a porous material mounted within an ink-supply tank;

providing a non-porous elongated member extending into said ink-supply tank, formed with an opening at at least the distal end thereof and formed with a passage essentially free of porous material, which extends longitudinally therealong said elongated member from said opening for conducting ink to the exterior of said ink-supply tank by at least capillary force;

locally compressing said ink absorbing member at least in the region thereof facing said opening by the engagement of said ink absorbing member by at least said distal end of said elongated member; and

withdrawing said ink from said ink-supply tank through said opening in and passage along said elongated member.

38. The method of claim 37, wherein said elongated member is provided so that said extending elongated member occupies substantially less than the entire area of the wall of the ink absorbing member from which it extends.

39. The method of claim 37, wherein said ink absorbing member is provided as a unitary piece of porous material.

40. The method of claim 39, wherein said unitary piece of porous material is provided so as to substantially fill the ink-supply tank.

41. The method of claim 39, wherein said unitary piece of porous material carries substantially all of the ink that said ink-supply tank was designed to hold.

42. The method of claim 37, and including the step of providing a first wall in said ink-supply tank from which said elongated member extends and a second wall in said ink-supply tank extending substantially in the same direction as said elongated member projects into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member projecting from said first wall at a position between the midpoint of said length of said first wall and said second wall.

43. The method of claim 37, including the further step of applying ink to said ink absorbing member under a pressure sufficiently low to substantially eliminate air bubbles in the ink absorbing member.

44. The method of claim 37, wherein the ink absorbing member is provided in the form of at least two pieces of porous material, each of said pieces of porous material abutting another of said pieces of porous material along respective surfaces thereof for the transfer of ink therebetween.

45. The method of claim 44, wherein said ink absorbing member substantially fills the ink-supply tank.

46. The method of claim 44, wherein said ink absorbing member carries substantially all of the ink that said ink-supply tank was designed to hold.

47. The method of claim 44, wherein at least two of said pieces of porous material are of different average pore size, the average pore size of the piece of porous material compressed by said elongated member being of the smallest of the average pore sizes of the pieces of porous material.

48. A dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank;

a printing mechanism for applying ink from the ink absorbing member to effect printing; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink to said printing means through said first wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wall essentially defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink from said opening toward said printing mechanism by at least capillary force, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening, said ink absorbing member being formed of a unitary piece of porous material, said unitary piece of porous material substantially filling the ink supply tank.

49. The dot matrix printer of claim 48, said elongated member occupying substantially less than the entire area of said first wall.

50. The dot matrix printer of claim 49, said elongated member occupying only a minor portion of the entire area of said first wall.

51. The dot matrix printer of claim 48, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

52. A dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank;

a printing mechanism for applying ink from the ink absorbing member to effect printing; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink to said printing means through said first wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wall essentially defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink from said opening toward said printing mechanism by at least capillary force, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening, said ink absorbing member being formed of a unitary piece of porous material, said unitary piece of porous material carrying substantially all of the ink that said ink-supply tank was designed to hold.

53. The dot matrix printer of claim 52, said elongated member occupying substantially less than the entire area of said first wall.

54. The dot matrix printer of claim 53, said elongated member occupying only a minor portion of the entire area of said first wall.

55. The dot matrix printer of claim 52, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

56. An ink-supply system for a dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink from said ink-supply tank through said wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wall defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink away from said opening by at least capillary force, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening, said ink absorbing member being formed of a unitary piece of porous material, said unitary piece of porous material substantially filling the ink supply tank.

57. The ink-supply system of claim 56, said elongated member occupying substantially less than the entire area of said first wall.

58. The ink-supply system of claim 57, said elongated member occupying only a minor portion of the entire area of said first wall.

59. The ink-supply system of claim 56, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

60. An ink-supply system for a dot matrix printer comprising:

an ink-supply tank having a first wall having a first side facing the interior of said tank and a second side facing the exterior of said tank;

an ink absorbing member formed of a porous material mounted with the ink-supply tank; and

an ink receiving and transmitting member positioned to receive ink from said ink absorbing member and constructed to transmit ink from said ink-supply tank through said wall, said ink receiving and transmitting member including a non-porous elongated member, said first side of said first wail defining a plane in the region thereof adjacent said elongated member, said elongated member extending into said ink-supply tank from said plane of said first wall, said ink receiving and transmitting member being formed with an opening at at least the distal end thereof and with a passage extending longitudinally therealong from said opening along the length of said elongated member for conducting ink away from said opening by at least capillary force, said elongated member engaging and compressing a portion of said ink absorbing member at least in the region of said ink absorbing member facing said opening, said unitary piece of porous material carrying substantially all of the ink that said ink-supply tank was designed to hold.

61. The ink-supply system of claim 60, said elongated member occupying substantially less than the entire area of said first wall.

62. The ink-supply system of claim 61, said elongated member occupying only a minor portion of the entire area of said first wall.

63. The ink-supply system of claim 60, wherein said ink-supply tank includes a second wall extending substantially in the same direction as said elongated member extends into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member extending from said plane of said first side of said first wall at a position between the midpoint of said length of said first wall and said second wall.

64. A method for supplying ink for a dot matrix printer comprising:

providing an ink absorbing member formed of a unitary piece of porous material mounted within an ink-supply tank and dimensioned to substantially fill the ink-supply tank;

providing a non-porous elongated member extending into said ink-supply tank, formed with an opening at at least the distal end thereof and formed with a passage extending longitudinally therealong from said opening for conducting ink to the exterior of said ink-supply tank by at least capillary force;

locally compressing said ink absorbing member at least in the region thereof facing said opening by the engagement of said ink absorbing member by at least said distal end of said elongated member; and

withdrawing said ink from said ink-supply tank through said opening in and passage along said elongated member.

65. The method of claim 64, wherein said elongated member is provided so that said extending elongated member occupies substantially less than the entire area of the wall of the ink absorbing member from which it extends.

66. The method of claim 64, and including the step of providing a first wall in said ink-supply tank from which said elongated member extends and a second wall in said ink-supply tank extending substantially in the same direction as said elongated member projects into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member projecting from said first wall at a position between the midpoint of said length of said first wall and said second wall.

67. A method for supplying ink for a dot matrix printer comprising:

providing an ink absorbing member formed of a unitary piece of porous material mounted within an ink-supply tank so that said ink absorbing member carries substantially all of the ink that the ink-supply tank was designed to hold;

providing a non-porous elongated member extending into said ink-supply tank formed with an opening at at least the distal end thereof and formed with a passage extending longitudinally therealong from said opening for conducting ink to the exterior of said ink-supply tank by at least capillary force;

locally compressing said ink absorbing member at least in the region thereof facing said opening by the engagement of said ink absorbing member by at least said distal end of said elongated member; and

withdrawing said ink from said ink-supply tank through said opening in and passage along said elongated member.

68. The method of claim 67, wherein said elongated member is provided so that said extending elongated member occupies substantially less than the entire area of the wall off the ink absorbing member from which it extends.

69. The method of claim 67, and including the step of providing a first wall in said ink-supply tank from which said elongated member extends and a second wall in said in-supply tank extending substantially in the same direction as said elongated member projects into said ink-supply tank, said first wall having a length as viewed in a direction therealong extending from said second wall, said elongated member projecting from said first wall at a position between the midpoint of said length of said first wall and said second wall.