Liquid injector

• US 20050073559A1
• Filed: 11/12/2002
• Published: 04/07/2005
• Est. Priority Date: 11/12/2001
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kumagai, Toshio, Matsumoto, Hitoshi, Aruga, Yoshiharu
• Granted Patent: US 7,156,507 B2
• Time in Patent Office: Days
• US Class Current: 347/85
• CPC Class Codes: B41J 2/14 Structure thereof only for on-demand ink jet heads
• CPC Class Codes: B41J 2/17506 Refilling of the cartridge
• CPC Class Codes: B41J 2/17509 Whilst mounted in the printer
• CPC Class Codes: B41J 2/17523 Ink connection
• CPC Class Codes: B41J 2/17556 Means for regulating the pressure in the cartridge
• CPC Class Codes: B41J 2/17596 Ink pumps, ink valves

Abstract

Provided is a liquid injecting apparatus equipped with a liquid injecting head, which is mounted on a carriage and moved reciprocally in a widthwise direction of a target, and a valve unit, which is mounted on the carriage to be supplied with liquid via a supply passage from a liquid retainer and to supply liquid to the liquid injecting head. The valve unit has a pressure chamber connected to the liquid retainer via the supply passage; a valve, which opens or closes the supply passage to supply liquid to the pressure chamber; and a flexible film member, which is displaced based on a negative pressure generated as liquid in the pressure chamber decreases to thereby operate the valve.

Claims

1. A liquid injecting apparatus equipped with a liquid injecting head, which is mounted on a carriage and moved reciprocally in a widthwise direction of a target, and a valve unit, which is mounted on said carriage to be supplied with liquid via a supply passage from a liquid retainer and to supply liquid to said liquid injecting head, said valve unit having:

a pressure chamber connected to said liquid retainer via said supply passage;

a valve, which opens or closes said supply passage to supply liquid to said pressure chamber;

an urging member, which has an urging force that urges said valve in a direction to close said supply passage; and

a flexible film member, which is displaced based on a negative pressure generated as liquid in said pressure chamber decreases, and which directly transmits the displacement to said valve to thereby cause said valve to operate against the urging force of said urging member.

2. The liquid injecting apparatus according to claim 1, wherein said liquid injecting apparatus has a main body to which said liquid retainer is attached, and said supply passage is comprised of a flexible tube through which liquid is supplied to said valve unit from said liquid retainer.

3. The liquid injecting apparatus according to claim 1, wherein liquid, supplied to said valve unit from said liquid retainer, is supplied by applying a positive pressure to liquid in said liquid retainer.

4. The liquid injecting apparatus according to claim 3, wherein said liquid retainer comprises an outer case set in an airtight state and a liquid pack of a flexible material, which is retained in the outer case and in which liquid is sealed, and the positive pressure is applied to liquid in said liquid retainer as compressed air, which is applied to a space portion between said outer case and said liquid pack.

5. The liquid injecting apparatus according to claim 3, wherein a liquid lead-out portion is formed in said liquid retainer in order to lead liquid to said supply passage from said liquid retainer, and said liquid lead-out portion is located at an upper portion of said valve unit along a gravitational direction, and wherein said positive pressure is generated based on a head difference between that liquid lead-out portion and the valve unit.

6. The liquid injecting apparatus according to claim 1, wherein said film member is a high-density polyethylene film or polypropylene film on which a nylon film coated with vinylidene chloride copolymer is laminated.

7. The liquid injecting apparatus according to claim 1, wherein said film member is a gas barrier layer formed between two synthetic resin films.

8. The liquid injecting apparatus according to claim 1, wherein said film member is a film formed of polyethylene or polypropylene on which is laminated a polyethylene-terephthalate film having deposited thereon alumina or silica.

9. The liquid injecting apparatus according to claim 6, wherein a pressure-receiving plate is arranged on said film member and said valve operates in accordance with movement of said pressure-receiving plate caused by displacement of said film member.

10. The liquid injecting apparatus according to claim 9, wherein said pressure-receiving plate is formed of polyethylene or polypropylene.

11. The liquid injecting apparatus according to claim 1, wherein said valve unit further has:

a supply hole positioned between said supply passage and said pressure chamber; and

a spring having an urging force for urging said valve in a direction of closing that supply hole, and said valve opens said supply hole upon reception of displacement of said film member against said urging force of said spring.

12. The liquid injecting apparatus according to claim 11, wherein said valve has a plate-like member and a rod member formed integral with the plate-like member in such a way as to protrude from the plate-like member, said rod member is inserted in said supply hole, said plate-like member receives the urging force of said spring, and said rod member receives a displacement reaction force by displacement of said film member.

13. The liquid injecting apparatus according to claim 12, wherein said supply hole comprises a support hole formed in a unit case for supporting the rod member of said valve in a slidable manner and a plurality of cutaway holes formed intermittently along a periphery of that support hole.

14. The liquid injecting apparatus according to claim 13, wherein a seal member formed in an annular shape is provided at said unit case in such a way as to surround an outer side of said supply hole and said supply hole is closed when the plate-like member of said valve abuts on the seal member.

15. The liquid injecting apparatus according to claim 13, wherein a seal member formed in an annular shape is fixed to the plate-like member of said valve and said supply hole is closed when said plate-like member abuts on the unit case in such a way as to surround an outer side of said supply hole.

16. The liquid injecting apparatus according to claim 1, wherein said valve unit is provided with a filter chamber positioned between said supply passage and said pressure chamber, and a filter member is provided in that filter chamber.

17. The liquid injecting apparatus according to claim 16, wherein said filter chamber has a passage for connecting a lower portion of the filter chamber to said pressure chamber, and said filter member is arranged in such a way as to cover said passage.

18. The liquid injecting apparatus according to claim 1, wherein said pressure chamber has an outlet that leads to said liquid injecting head, and the outlet is formed at a topmost portion of said pressure chamber along a gravitational direction.

19. The liquid injecting apparatus according to claim 1, wherein said film member is coated with a water non-transmittive film.

20. The liquid injecting apparatus according to claim 1, wherein a lid for sealing an outer surface of said film member is provided, wherein an air flow passage and an air release port are formed in said lid, and wherein pressure inside said lid is released to atmosphere via said passage and said air release port.

21. The liquid injecting apparatus according to claim 20, wherein said air flow passage comprises a groove portion formed in a wall of said lid and a second film member, which covers said groove portion when in close contact with the wall of said lid, and wherein said air release port is formed at an end portion of said air flow passage.

22. The liquid injecting apparatus according to claim 9, wherein a plurality of restriction projections facing said pressure-receiving plate are formed in the pressure chamber in order to restrict displacement of said film member.

23. The liquid injecting apparatus according to claim 9, wherein a plurality of restriction projections facing an inner wall of said pressure chamber are formed on said pressure-receiving plate in order to restrict displacement of said film member.

24. A valve unit, which is mounted on a liquid injecting apparatus for injecting liquid from a liquid injecting head mounted on a carriage that moves in relative to a target, and which is supplied with liquid via a supply passage from a liquid retainer located apart from said carriage, said valve unit having:

a pressure chamber connected to said liquid retainer via said supply passage;

a valve, which opens or closes said supply passage to supply liquid to said pressure chamber; and

a flexible film member, which constitutes a part of said pressure chamber, and which is displaced based on a negative pressure generated as liquid in said pressure chamber decreases to thereby cause said valve to operate.

25. A method of manufacturing a valve unit in which a pressure chamber comprises a recess portion formed in a unit case and a flexible film member coating that recess portion, and which valve unit has a valve for leading liquid from a liquid retainer into the pressure chamber by detecting a negative pressure originated from a decrease in liquid in said pressure chamber by means of said film member, said method comprising:

a step of heating said unit case;

a step of placing said film member on the unit case in such a way as to cover the recess portion of the heated unit case; and

a step of thermally depositing said film member on the unit case to thereby form said pressure chamber.

26. A method of manufacturing a valve unit, in which a pressure chamber comprises a recess portion formed in a unit case and a flexible film member coating that recess portion, wherein said valve unit has a valve for leading liquid from a liquid retainer into the pressure chamber by detecting a negative pressure originated from a decrease in liquid in said pressure chamber by means of said film member, said method comprising:

a step of attaching a pressure-receiving plate to a top surface of said film member;

a step of placing said film member, with said attached pressure-receiving plate, on the unit case in such a way as to cover the recess portion of said unit case; and

a step of thermally depositing said placed film member on the unit case to thereby form said pressure chamber.

27. The method of manufacturing a valve unit according to claim 26, wherein in the step of placing said film member, a second surface of said film member opposite to the top surface is caused to face said recess portion of said unit case, and

wherein, in the step of thermally depositing said placed film member on said unit case, said film member is thermally deposited on the periphery of said recess portion with said pressure-receiving plate pressed toward the recess portion by a flat surface of a heater block.

28. The method of manufacturing a valve unit according to claim 26, wherein, in the step of thermally depositing said placed film member on said unit case, said pressure-receiving plate is pressed toward the recess portion by a projection of a heater block and said placed film member is thermally deposited on a periphery of said recess portion.

29. The method of manufacturing a valve unit according to claim 28, wherein said projection of said heater block is formed of a heat insulating material.

30. The method of manufacturing a valve unit according to claim 26, wherein in the step of thermally depositing said placed film member on said unit case, the placed film member is pressure-bonded to the unit case by a heater block and said film member is thermally deposited on said unit case with air between the heater block and the unit case being sucked and discharged from a hole in the heater block.

31. An ink jet type recording apparatus equipped with a recording head, which recording head is mounted on a carriage and is moved reciprocally in a widthwise direction of recording paper;

and an ink-supply valve unit, which ink-supply valve unit is mounted on said carriage to be supplied with ink via an ink supply passage from an ink cartridge and to supply the ink to said recording head, said ink-supply valve unit having;

a pressure chamber connected to said ink cartridge via said ink supply passage;

a valve which opens or closes said ink supply passage to supply the ink to said pressure chamber;

a drive body, which detects a negative pressure generated in the pressure chamber as the ink is consumed by said recording head and operates said valve; and

a negative-pressure holding spring, which abuts on said drive body and urges it in a direction to expand the volume of said pressure chamber.

32. The ink jet type recording apparatus according to claim 31, wherein said ink-supply valve unit is further provided with a seal spring, which urges said valve in a direction of closing said ink supply passage.

33. The ink jet type recording apparatus according to claim 31, wherein said drive body is comprised of a flexible film member, which constitutes a part of said pressure chamber.

34. The ink jet type recording apparatus according to claim 33, wherein a pressure-receiving plate is arranged on said film member, and said valve operates in accordance with movement of said pressure-receiving plate caused by displacement of said film member.

35. The ink jet type recording apparatus according to claim 34, wherein said negative-pressure holding spring is arranged in such a way that its urging direction matches with a direction of the movement of said pressure-receiving plate.

36. The ink jet type recording apparatus according to claim 35, wherein said negative-pressure holding spring is a coil spring, and said coil spring is arranged in such a way as to be able to abut on a nearly the center of said pressure-receiving plate.

37. The ink jet type recording apparatus according to claim 35, wherein said negative-pressure holding spring is comprised of a coil spring, and said coil spring is arranged in such a way as to be able to abut on near a periphery of said pressure-receiving plate.

38. The ink jet type recording apparatus according to claim 35, wherein said negative-pressure holding spring is comprised of a plurality of coil springs, each of which is arranged in such a way as to be able to abut on near a periphery of said pressure-receiving plate.

39. The ink jet type recording apparatus according to claim 35, wherein said negative-pressure holding spring is comprised of a plate spring whose both ends in a lengthwise direction are supported and its center portion is arranged in such a way as to be able to abut on a nearly the center of said pressure-receiving plate.

40. The ink jet type recording apparatus according to claim 32, wherein said ink-supply valve unit further has:

a supply hole positioned between said ink supply passage and said pressure chamber; and

a seal spring having an urging force for urging said valve in a direction of closing that supply hole, and said valve opens said supply hole upon reception of displacement of said film member against said urging force of said seal spring.

41. The ink jet type recording apparatus according to claim 40, wherein said valve has a plate-like member and a rod member formed integral with the plate-like member in such a way as to protrude from the plate-like member, said rod member is inserted in said ink supply hole, said plate-like member receives the urging force of said seal spring, and said rod member receives a displacement reaction force by displacement of said film member.

42. The ink jet type recording apparatus according to claim 41, wherein said ink supply hole comprises a support hole formed in a unit case for supporting the rod member of said valve in a slidable manner and a plurality of cutaway holes formed intermittently along a periphery of that support hole.

43. The ink jet type recording apparatus according to claim 42, wherein a seal member formed in an annular shape is provided at said unit case in such a way as to surround an outer side of said supply hole and said supply hole is closed when the plate-like member of said valve abuts on the seal member.

44. The ink jet type recording apparatus according to claim 40, wherein said negative-pressure holding spring is so constructed as to be further compressible even after said movable valve makes a maximum movement based on a change in the volume of said pressure chamber.

45. The ink jet type recording apparatus according to claim 41, wherein said ink cartridge is attached to a main body of the recording apparatus, and said ink supply passage comprises a flexible ink supply tube via which the ink is supplied to said ink-supply valve unit from the ink cartridge.

46. The ink jet type recording apparatus according to claim 45, wherein, as a positive pressure is applied to the ink in said ink cartridge, the ink is supplied to the ink-supply valve unit from said ink cartridge.

47. The ink jet type recording apparatus according to claim 46, wherein said ink cartridge comprises an outer case rendered in an airtight state and an ink pack of a flexible material retained in the outer case and having ink sealed therein, and as compressed air is applied to a space portion between said outer case and said ink pack, the positive pressure is applied to the ink in said ink cartridge.

48. The ink jet type recording apparatus according to claim 46, wherein an ink lead-out portion is formed in said ink cartridge to lead the ink to said ink-supply valve unit from said ink cartridge, said ink lead-out portion is arranged in an upper portion of said ink-supply valve unit along a gravitational direction, and said positive pressure is generated based on a head difference between said ink lead-out portion and the valve unit.

49. A liquid injecting apparatus equipped with a liquid storing member, which stores liquid;

a liquid injecting head, which injects liquid;

a liquid supply passage, for supplying said liquid to said liquid injecting head from said liquid storing member; and

a valve unit, which is provided in the liquid supply passage and temporarily stores said liquid, said valve unit having;

a supply chamber, into which liquid to be supplied from said liquid storing member flows;

a pressure chamber, in which liquid to be lead out to said liquid injecting head is stored; and

a valve, which connects said supply chamber to said pressure chamber by a negative pressure generated in said pressure chamber as said liquid is injected from said liquid injecting head,

wherein a liquid outlet, which is led out to said liquid injecting head, is provided in said pressure chamber at a position equal to or below 25% of a volume of said pressure chamber in a gravitational direction.

51. The liquid injecting apparatus according to claim 49 or 50, wherein said liquid outlet is provided at a lowermost portion of said pressure chamber along the gravitational direction.

52. The liquid injecting apparatus according to claim 49, wherein an upper space of said pressure chamber, positioned above a center of the pressure chamber along the gravitational direction, is formed smaller than a lower space of said pressure chamber positioned below the center.

53. The liquid injecting apparatus according to claim 52, wherein said upper space of said pressure chamber becomes narrower in the upward direction.

54. The liquid injecting apparatus according to claim 53, wherein said upper space of said pressure chamber becomes narrower toward a peripheral portion from near the center of said pressure chamber.

55. The liquid injecting apparatus according to claim 52, wherein a volume-increasing portion is formed in said lower space of said pressure chamber.

56. The liquid injecting apparatus according to claim 49, wherein said pressure chamber comprises a recess portion formed in a unit case of said valve unit and a flexible member, which covers an opening of that recess portion and deforms, based on a negative pressure in the pressure chamber, to open said valve, and

an inclined surface is formed at a peripheral portion of said recess portion in such a way that said recess portion becomes wider in the direction toward said flexible member.

50. A liquid injecting apparatus equipped with a liquid storing member, which stores liquid;

a liquid injecting head, which injects liquid;

a liquid supply passage for supplying said liquid to said liquid injecting head from said liquid storing member;

a valve unit, which is provided in the liquid supply passage and temporarily stores said liquid; and

a passage valve, which is arranged in said liquid supply passage at upstream of the valve unit to open and close the liquid supply passage;

said valve unit having;

a supply chamber, into which liquid to be supplied from said liquid storing member flows;

a pressure chamber, in which liquid to be lead out to said liquid injecting head is stored; and

a valve, which connects said supply chamber to said pressure chamber by a negative pressure generated in said pressure chamber as said liquid is injected from said liquid injecting head,

wherein a liquid outlet, which is led out to said liquid injecting head is provided in said pressure chamber at a position equal to or below 40% of a volume of said pressure chamber in a gravitational direction.

57. A valve unit, which is provided in a liquid supply passage for supplying liquid from a liquid storing member for storing liquid to a liquid injecting head that injects liquid, wherein said valve unit comprises:

a supply chamber, into which flows liquid to be supplied from said liquid storing member;

a pressure chamber, in which is stored liquid to be lead out to said liquid injecting head; and

a valve, which connects said supply chamber to said pressure chamber by a negative pressure generated in said pressure chamber as said liquid is injected from said liquid injecting head,

wherein a liquid outlet, which is led out to said liquid injecting head, is provided in said pressure chamber at a position equal to or below 25% of a volume of said pressure chamber in a gravitational direction.

58. A valve unit, which is provided at a position downstream of a passage valve for controlling communication of liquid in a liquid supply passage for supplying liquid from a liquid storing member for storing liquid to a liquid injecting head for injecting liquid, and which has

a supply chamber, into which flows liquid to be supplied from said liquid storing member;

a pressure chamber, in which is stored liquid to be lead out to said liquid injecting head; and

a valve, which connects said supply chamber to said pressure chamber by a negative pressure generated in said pressure chamber as said liquid is injected from said liquid injecting head,

wherein liquid outlet, which is led out to said liquid injecting head, is provided in said pressure chamber at a position equal to or below 40% of a volume of said pressure chamber in a gravitational direction.

59. A liquid injecting apparatus comprising:

a carriage, which adheres liquid to a target by injecting liquid from a plurality of nozzles of a liquid injecting head while moving relative to said target;

a liquid retainer, which is provided at a position apart from said carriage and which stores liquid to be supplied to said carriage;

a flexible supply tube, which is located between said liquid retainer and said carriage, and which forms a liquid passage extending to the carriage from the liquid retainer; and

a valve mechanism, mounted on said carriage and provided in a liquid passage extending to said liquid injecting head from said supply tube,

wherein said liquid retainer is arranged above said valve mechanism by a predetermined height within a range over which said carriage moves.

60. The liquid injecting apparatus according to claim 59, wherein said liquid retainer is arranged near a center in the range over which said carriage moves.

61. The liquid injecting apparatus according to claim 59, wherein said valve mechanism has a pressure chamber positioned within said valve mechanism in a position towards en said liquid injecting head, and said valve mechanism opens said liquid passage based on a negative pressure generated by a decrease in liquid in said pressure chamber in accordance with injection of liquid from said nozzles.

62. The liquid injecting apparatus according to claim 59, wherein said predetermined height is a position head equal to or greater than a sum of a pressure head originated from a pressure loss that occurs between said liquid retainer and said valve mechanism and a pressure head originated from a pressure needed when said liquid renders said valve mechanism in an open state.

63. The liquid injecting apparatus according to claim 62, wherein said predetermined height is a position head equal to the sum of the pressure head originated from the pressure loss from said liquid retainer to said valve mechanism and the pressure head originated from the pressure needed when said liquid renders said valve mechanism in an open state.

64. The liquid injecting apparatus according to claim 59, wherein said predetermined height is a position head equal to or greater than a sum of a pressure head originated from a pressure loss from said liquid retainer to said valve mechanism, a pressure head originated from a pressure needed when said liquid renders said valve mechanism in an open state and a change in a position head of liquid caused by consumption of liquid in said liquid retainer.

65. The liquid injecting apparatus according to claim 64, wherein said predetermined height is a position head equal to the sum of the pressure head originated from the pressure loss from said liquid retainer to said valve mechanism, the pressure head originated from the pressure needed when said liquid renders said valve mechanism in an open state and the change in the position head of liquid in said liquid retainer.

66. The liquid injecting apparatus according to claim 59, wherein a length and diameter of said supply tube are determined in such a way that a sum of a pressure of said valve mechanism, when said valve mechanism is opened, and a pressure loss caused as liquid flows into said liquid injecting head from said liquid retainer is lower than a pressure produced as said liquid retainer is positioned above said valve mechanism by said predetermined height.

67. A liquid injecting apparatus, which is equipped with a carriage provided with a liquid injecting head and a liquid retaining portion, mounted on said carriage and retaining liquid to be supplied to said liquid injecting head, and which liquid injecting apparatus injects liquid to a target from said liquid injecting head, and which liquid injecting apparatus comprises a valve unit, which is provided between said liquid injecting head and said liquid retaining portion, said valve unit having:

a supply chamber within said valve unit in a position towards said liquid retaining portions;

a pressure chamber within said valve unit in a position towards said liquid injecting head;

a valve, which connects or disconnects said supply chamber to or from said pressure chamber,

an urging member, having an urging force which urges said valve in a direction of closing said supply passage, and

a drive body, which senses a negative pressure originated from a decrease in liquid in said pressure chamber and connects said supply chamber to the pressure chamber by means of said valve against said urging force of said urging member.

68. The liquid injecting apparatus according to claim 67, wherein said liquid retaining portion is arranged above said supply chamber of said valve unit.

69. The liquid injecting apparatus according to claim 67, wherein said valve unit is provided integral with said carriage, and wherein said liquid retaining portion is attachable to and detachable from said carriage.

70. The liquid injecting apparatus according to claim 69, wherein a supply needle, to be inserted into said liquid retaining portion, is formed in said valve unit;

and said liquid retaining portion is provided with a supply portion, in which said supply needle is to be inserted, and a valve mechanism, that is opened with said supply needle inserted and is closed with said supply needle detached is provided.

71. The liquid injecting apparatus according to claim 67, wherein said valve unit is provided integral with said liquid retaining portion, and said liquid retaining portion, together with said valve unit, is attachable to and detachable from said carriage.

72. The liquid injecting apparatus according to claim 71, wherein a supply needle to be inserted into said valve unit is formed in said carriage and said valve unit is provided with a valve mechanism that is opened with said supply needle inserted and is closed with said supply needle detached.

73. The liquid injecting apparatus according to claim 69, wherein said drive body is comprised of a flexible film member, and wherein said valve is operated as the film member is displaced upon reception of a negative pressure originated from a decrease in liquid in the pressure chamber.

74. A liquid retainer, which is mounted on a carriage having a liquid injecting head, and having a liquid retaining portion retaining liquid to be supplied to the liquid injecting head, characterized in that

the liquid retaining portion is mounted on a valve unit, which valve unit is fixed to the carriage, and

when a negative pressure originated from a reduction in liquid in a pressure chamber of the valve unit connected to the liquid injecting head is sensed, a valve, which connects and disconnects a supply chamber of the valve unit connected to the liquid retaining portion from the pressure chamber, is opened so that liquid in the liquid retaining portion is supplied to the pressure chamber.

75. The liquid retainer according to claim 74, wherein the liquid retaining portion is mounted on the carriage in such a way as to be positioned higher than the supply chamber of the valve unit, and a bottom of the liquid retaining portion, mounted on the carriage, is inclined toward a supply port of the liquid retaining portion, which is connected to the supply chamber.

76. A liquid retainer to be detachably mounted on a carriage having a liquid injecting head, said liquid retainer comprising:

a liquid retaining portion, retaining liquid, and a valve unit within said liquid retainer in a position towards said liquid injecting head,

the valve unit being provided with a valve, which connects or disconnects a supply chamber defined on the liquid retaining portion side to or from a pressure chamber defined on the liquid injecting head side, and a drive body, which senses a negative pressure originated from a decrease in liquid in the pressure chamber and operates the valve.