Continuous paper feed prevention lock mechanism for printer

• US 5,305,068 A
• Filed: 04/23/1992
• Issued: 04/19/1994
• Est. Priority Date: 04/23/1991
• Status: Expired due to Fees

• Current Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Original Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Inventors: Yamaguchi, Hiroyuki, Sato, Tsutomu, Takano, Masatoshi, Saito, Taizo
• Primary Examiner(s): Grimley, A. T.
• Assistant Examiner(s): Brase , Sandra L.
• Application Number:
  US07/872,834
• Time in Patent Office: 726 Days
• Field of Search: 355/308, 355/309, 355/316, 355/317, 271/264, 271/266, 400/616, 400/616.1, 400/616.2, 226/24, 226/33, 226/43, 226/59, 226/74, 226/75, 226/79
• US Class Current: 399/317
• CPC Class Codes: B41J 11/30 Pin traction elements other than wheels, e.g. pins on endless bands
• CPC Class Codes: B41J 15/04 Supporting, feeding, or guiding devices; Mountings for web rolls or spindles
• CPC Class Codes: B65H 20/20 by web-penetrating means, e.g. pins

Abstract

A printer, for printing on continuous recording paper, includes tractors disposed in the recording paper feed path of the printer, with each of the tractors circumferentially travelling in synchronism with movement of the continuous recording paper when the tractors engage feed holes of the continuous paper. When no printing operation is performed, travel of the tractors can be prevented by operation of an electromagnetic clutch, or a combination of one way clutches. Further, the printer uses an electrophotographic method wherein when no printing operation is performed, a transfer charger or fixing roller can be retracted from an operational position. A lever, associated with movement of the transfer charge or fixing roller, is pressed against and locked with the pulley fixed to the rotating shaft of each of the tractors to thereby prohibit the movement of the tractor. Further, a swingable arm can be provided having an engaging projection capable of being locked with the feed holes of the continuous recording paper. The swingable arm is swung in association with the movement of the transfer charger or fixing roller, which can be retracted from the operational position when no printing operation is performed. Thus, the engaging projection is engaged with the feed hole of the continuous recording paper to thereby regulate the movement of the continuous recording paper.

Claims

1. A paper feed lock mechanism adapted to be used with a printer for printing continuous recording paper, said paper feed lock mechanism comprising recording paper movement regulation means for regulating movement of said continuous recording paper during predetermined times when no printing operation is performed by said printer, said regulation means comprising means for applying a load to said continuous recording paper for preventing movement of said continuous recording paper, said regulation means regulates movement of the continuous recording paper when a fixing roll is separated from the continuous recording paper.

2. The paper feed lock mechanism for a printer according to claim 1, wherein said continuous paper comprises feed holes defined along side edges of said paper and said printer is provided with tractor belts which each comprise projections that are adapted to engage said feed holes, said tractor belts circumferentially traveling in synchronism with said continuous recording paper;

wherein said recording paper movement regulation means regulates said circumferential traveling movement of said tractor belts.

3. The paper feed lock mechanism for a printer according to claim 2, wherein each of said tractor belts is stretched between drive pulleys mounted on shafts, respectively, and at least one of said shafts is connected to a member through a clutch means which enables said shaft to be connected or disconnected from driving said member, said member being stationary when a printing operation is not being performed and having a rotational load larger than a predetermined value when rotated.

4. The paper feed lock mechanism for a printer according to claim 3, wherein said member which is stationary when a printing operation is not being performed, and which has a rotational load larger than a predetermined value when rotated, comprises means for driving said tractor belts to circumferentially travel.

5. The paper feed lock mechanism for a printer according to claim 2, wherein each of said tractor belts is stretched between a drive pulley mounted on a drive shaft and a follower pulley mounted on a follower shaft, each of said tractor belts being caused to circumferentially travel in a direction toward which said continuous paper is fed, through a drive force transmission means mounted on said drive shaft and engaged with said drive shaft when rotated in the direction toward which said continuous paper is fed, to thereby transmit a rotating force to said drive shaft through one way engagement means, and loosely rotated when rotated in a direction opposite to said direction toward which said continuous paper is fed, said recording paper movement regulation means further comprising:

first drive force transmission means integrally formed with said drive force transmission means mounted on said shaft; and

second drive force transmission means mounted on said follower shaft and loosely rotated when rotated in the direction toward which said continuous paper is fed, said second drive force transmission means being engaged with said follower shaft to thereby transmit a rotating force to said follower shaft through one way engagement means when rotated in an opposite direction, said first drive force transmission means being coupled with said second drive force transmission means through an association means; and

said first drive force transmission means and said second drive force transmission means are arranged such that when said tractor belts circumferentially travel, said second drive force transmission means is rotated at a speed higher than that of said follower shaft.

6. The paper feed lock mechanism for a printer according to claim 5, wherein said first drive force transmission means and said second drive force transmission means comprise toothed pulleys, and said association means is a toothed belt.

7. The paper feed lock mechanism for a printer according to claim 2, wherein each of said tractor belts is stretched between drive pulleys mounted on a drive shaft and a follower pulley mounted on a follower shaft which is adapted to circumferentially travel in a direction toward which said continuous paper is fed, through a drive force transmission means mounted on said drive shaft and engaged with said drive shaft when rotated in a direction toward which said continuous paper is fed to thereby transmit a rotating force to said drive shaft through one way engagement means, said follower pulley being loosely rotated when rotated in a opposite direction, said recording paper movement regulation means comprising:

said follower pulley which is mounted on said follower shaft so that when said follower pulley is rotated in the direction toward which said continuous paper is fed, said follower pulley engages said follower shaft to thereby transmit a rotational force to said follower shaft through one way engagement means, and so that when said follower pulley is rotated in an opposite direction, said follower pulley is loosely rotated;

a first drive force transmission means integrally attached to said drive force transmission means which is mounted on said drive shaft;

a second drive force transmission means mounted on said follower shaft so that said first and second drive force transmission means cannot be relatively rotated, wherein said first drive force transmission means is coupled with said second drive force transmission means through an association means; and

said first drive force transmission means and said second drive force transmission means being arranged such that when said tractor belts circumferentially travel, said second drive force transmission means is rotated at a speed higher than the speed of second follower shaft.

8. The paper feed lock mechanism for a printer according to claim 7, wherein said first drive force transmission means and said second drive force transmission means comprise toothed pulleys, and said association means is a toothed belt.

9. The paper feed lock mechanism for a printer according to claim 2, wherein said recording paper movement regulation means comprises a stopper means associated with a change in status of said printer, from a printing operation to a printing operation waiting state, for regulating rotation of a shaft member on which a pulley for stretching said tractor belts is mounted.

10. The paper feed lock mechanism for a printer according to claim 9, wherein said stopper means comprises a swingable arm member having an engagement portion at an extreme end of said arm member, said arm member being adapted to swing in association with the change of status of said printer from a printing operation state to a printing operation waiting state, and an engagement member fixed on said shaft member and engaged with said arm member.

11. The paper feed lock mechanism for a printer according to claim 10, wherein said printer is provided with a movement member which is adapted to move between the time when a printing operation is performed and a time when said printer is waiting for a printing operation to be performed, and wherein said arm member is swung in association with said movement member.

12. The paper feed lock mechanism for a printer according to claim 10, wherein said printer comprises an electrophotographic printer provided with a fixing unit for performing a fixing action by using a pair of fixing rolls, wherein, when said printer is waiting for a printing operation to be performed, at least one of said fixing rolls is spaced apart and retracted from said continuous recording paper, wherein said arm member is swung in association with retraction of said at least one roller.

13. The paper feed lock mechanism for a printer according to claim 10, said printer comprising an electrophotographic printer wherein, when said printer is waiting for a printing operation to be performed, a transfer charger is retracted from a transfer position and said arm member is swung in association with retraction of said transfer charger.

14. The paper feed lock mechanism for a printer according to claim 2, wherein said recording paper movement regulation means comprises an engagement member which is adapted to engage feed holes of said continuous recording paper in association with a change of state of said printer from a printing operation state to a printing operation waiting state.

15. The paper feed lock mechanism for a printer according to claim 14, wherein said engagement member is adapted to be engaged with the feed holes of said continuous recording paper, at the time that a swingable arm member having an engagement projection adapted to be engaged with the feed holes of said continuous recording paper, is adapted to be swung in association with the change of state of said printer from a printing operation state to a printing operation waiting state, said engagement projection being located at an extreme end of said swingable arm member.

16. The paper feed lock mechanism for a printer according to claim 15, wherein said printer is provided with a movement member which is adapted to be moved between the time when a printing operation is performed and the time when said printer is waiting for a printing operation to be performed, and wherein movement of said arm member is associated with said movement member.

17. The paper feed lock mechanism for a printer according to claim 15, wherein said printer comprises an electrophotographic printer and is provided with a fixing unit for performing a fixing action by using a pair of fixing rolls, wherein, when said said printer is waiting for a printing operation to be performed, at least one of said pair of fixing rolls is spaced apart and retracted from said continuous recording paper, wherein said arm member is associated with retraction of one roller of said pair of fixing rolls.

18. A paper feed lock mechanism for a printer according to claim 15, wherein said printer comprises an electrophotographic printer, wherein, when said printer is waiting for a printing operation to be performed, a transfer charge is retracted from a transfer position, wherein movement of said engagement member is associated with retraction of said transfer charge.

19. The paper feed lock mechanism for a printer according to claim 1, wherein said recording paper movement regulation means comprises a pair of rollers adapted to be pressed against each other with said continuous recording paper held between said pair of rollers, wherein at least one of said rollers is rotated in synchronism with feeding movement of said continuous recording paper.

20. The paper feed lock mechanism for a printer according to claim 19, wherein said printer comprises an electrophotographic printer and said pair of rollers are disposed on a paper discharge side of a fixing unit which forms part of said printer.

21. The paper feed lock mechanism for a printer according to claim 1, wherein said recording paper movement regulation means includes gripping means operatively associated with a change of state of said printer from a printing operation state to a printing operation waiting state, said gripping means comprising means for gripping said continuous recording paper to prevent movement of said recording paper when said printer is waiting for a printing operation to be performed.

22. The paper feed lock mechanism for a printer according to claim 21, wherein said gripping means includes a fixing member fixedly disposed on one side of the feed path of said continuous recording paper, and a pressing member fixed to an arm member swingably supported by a chassis member on an opposite side of said feed path, across said continuous recording paper, wherein when said printer is waiting for a printing operation to be performed, said continuous recording paper is gripped between said pressing member and said fixing member, by the swinging motion of said arm member, to thereby prevent movement of said continuous recording paper.

23. The paper feed lock mechanism for a printer according to claim 22, wherein said printer is provided with a moving member which is adapted to be moved between the time when a printing operation is performed and the time when said printer is waiting for a printing operation to be performed, wherein said arm member is associated with said movement member.

24. The paper feed lock mechanism for a printer according to claim 22, wherein said printer comprises an electrophotographic printer provided with a fixing unit for performing a fixing operation by using a pair of fixing rolls, wherein, when said printer is waiting for a printing operation to be performed, at least one of said pair of fixing rolls is spaced apart from and retracted from said continuous recording paper, wherein movement of said arm member is associated with retraction of a roller of said at least one pair of fixing rolls.

25. The paper feed lock mechanism for a printer according to claim 22, wherein said printer comprises an electrophotographic printer, wherein when said printer is waiting for a printing operation to be performed, a transfer charger is retracted from a transfer position, wherein movement of said arm member is associated with retraction of said transfer charger.

26. The paper feed lock mechanism for a printer according to claim 1, wherein said recording paper movement regulation means comprises an arm member having a guide portion defined at one end of said arm member and an engagement projection adapted to be engaged with a feed hole of said continuous recording paper, said engagement projection located at a second end of said arm member, said arm member adapted to be swung in a direction perpendicular to the direction toward which said continuous recording paper is fed, urging means for urging and swinging said arm member to press said guide portion against said continuous recording paper and to bend the feed path of said paper, wherein, when tension is applied to said continuous recording paper, said arm member is swung against the urging force of said urging means to cause said engagement projection to engage the feed hole of said continuous recording paper.

27. A paper movement locking mechanism adapted for use in a printer for printing on continuous paper, said printer being capable of printing during printing periods and not printing during non-printing periods, said mechanisms including a locking device comprising means for preventing movement of said continuous recording paper during predetermined non-printing periods, said preventing means comprising means applying a load to said paper for preventing movement of said continuous paper, said preventing means regulates movement of the continuous paper when a fixing roller is separated from said paper.

28. A mechanism in accordance with claim 27, wherein said movement preventing means comprises a one-way clutch.

29. A mechanism in accordance with claim 28, wherein said printer includes means for feeding said continuous paper through said printer, said feeding means including at least one belt positioned about a plurality of pulleys, at least one of said pulleys being connected to one end of a first shaft, said first shaft being connected at an opposite end to said one-way clutch.

30. A mechanism in accordance with claim 29, wherein each said belt has a plurality of teeth on an interior belt surface, said belt teeth being adapted to engage teeth on an exterior surface of said pulleys.

31. A mechanism in accordance with claim 29, wherein an exterior surface of each said belt comprises a plurality of projections which are adapted to engage holes in said continuous paper.

32. A mechanism in accordance with claim 29, wherein said clutch, when engaged, couples said first shaft to a drive motor, wherein when said drive motor is stationary it comprises a rotational load on said first shaft to prevent movement of said continuous paper.

33. A mechanism in accordance with claim 29, further comprising a drive gear attached to said one-way clutch, wherein said drive gear, when rotated in a predetermined direction, engages said one-way clutch to permit said first shaft to be driven in accordance with the direction of feeding movement of said paper.

34. A mechanism in accordance with claim 33, wherein said drive gear, when driven in a direction opposite to said predetermined direction, disengages said one-way clutch and causes said drive gear to be loosely rotated with respect to said first shaft.

35. A mechanism in accordance with claim 29, wherein said feeding means further comprises means for driving said fanfold paper through said printer at a speed which is faster than the circumferential travel speed of each said belt during a normal printing operation.

36. A mechanism in accordance with claim 29, further comprising a second one-way clutch which is adapted to be attached to a second pulley at one end of a second shaft which is attached to said second pulley.

37. A mechanism in accordance with claim 36, wherein said second one-way clutch, when disengaged in a predetermined rotational direction, comprises means for permitting said second pulley to be loosely rotated with respect to said second shaft.

38. A mechanism in accordance with claim 37, wherein said second one-way clutch, when engageably rotated in a predetermined rotational direction, comprises means for rotating said second shaft in accordance with rotation of said second pulley.

39. A mechanism in accordance with claim 36, wherein said first and second clutches together comprises means for locking each said belt in a predetermined position to prevent movement of paper on said belt.

40. A mechanism in accordance with claim 38, wherein said second pulley has a diameter smaller than the diameter of said first pulley.

41. A mechanism in accordance with claim 27, wherein said one-way clutch comprises an electromagnetic clutch.

42. A mechanism in accordance with claim 27, wherein said movement preventing means comprises a movable member which is adapted to engage paper feeding means in said printer in order to prevent movement of said paper.

43. A mechanism in accordance with claim 42, wherein said movable member comprises a brake lever.

44. A mechanism in accordance with claim 42, wherein said paper feeding means comprises at least one belt and at least two rotatable pulleys positioned on respective first and second shafts.

45. A mechanism in accordance with claim 44, wherein said moveable member comprises a brake lever which is adapted to fix the position of at least one of said pulleys to prevent each of said belts from moving.

46. A mechanism in accordance with claim 45, wherein said brake lever is supported by a swing lever which is attached to a chassis for supporting each said belt.

47. A mechanism in accordance with claim 45, wherein said brake lever is supported by a bar, said brake lever being swingable both upwardly and downwardly.

48. A mechanism in accordance with claim 45, wherein one end of said brake lever comprises an irregularly shaped surface which is adapted to engage a friction pulley attached to one of said first and second shafts.

49. A mechanism in accordance with claim 48, wherein said friction pulley has an outer periphery which is spaced apart from said end of said brake lever by a predetermined distance when said printer is engaged in a printing operation, and which engages said brake lever during said predetermined non-printing periods.

50. A mechanism in accordance with claim 42, wherein said movable member comprises a swingable stop lever.

51. A mechanism in accordance with claim 50 , wherein said stop lever is pivotally connected to an arm of a corona charger.

52. A mechanism in accordance with claim 51, said paper feeding means comprising at least one belt adapted to drive said continuous paper, at least one pulley, and at least two spaced shafts.

53. A mechanism in accordance with claim 52, wherein said stop lever is a pivotal member which is adapted to engage a friction pulley mounted on one of said shafts in order to prevent movement of each said belt.

54. A mechanism in accordance with claim 53, wherein said apparatus further comprises a slidable actuation lever having an actuating portion at one end.

55. A mechanism in accordance with claim 54, wherein said one end of said actuation lever is adapted to engage an actuation arm which is adapted to pivotally move said stop lever.

56. A mechanism in accordance with claim 52, wherein said step lever includes a shaft portion and a lever portion with one end having an irregular surface, said irregular portion being adapted to engage a friction pulley mounted on one of said shafts.

57. A mechanism in accordance with claim 50, further comprising a spring for biasing said stop lever into a first position during printing operation of said printer.

58. A mechanism in accordance with claim 50, wherein said feeding means include at least one belt, at least two rotatable shafts, and at least one friction pulley positioned on at least one of said shafts, wherein said stop lever is adapted to be rotated in a first direction in order to engage said friction pulley in order to prevent rotation of said at least one shaft and movement of said paper during one of said predetermined non-printing periods.

59. A mechanism in accordance with claim 58, wherein said stop lever is rotated in a direction opposite to said first direction in order to move said stop lever into a position in which it is spaced from said pulley, during a time other than one of said predetermined non-printing periods.

60. A mechanism in accordance with claim 27, wherein said movement preventing means comprises a pair of rollers.

61. A mechanism in accordance with claim 60, wherein said printer includes an image fixing unit, said pair of rollers forming part of said image fixing unit.

62. A mechanism in accordance with claim 61, wherein said pair of rollers comprise holding rollers which are coupled to a drive source for rotating a heat roller in said fixing unit, said drive source comprising means for preventing said holding rollers from rotating during said predetermined non-printing periods.

63. A mechanism in accordance with claim 27, wherein said movement preventing means comprises a roller positioned between an image fixing unit, forming part of said printer, and means for feeding paper through said printer.

64. A mechanism in accordance with claim 63, wherein said feeding means comprises at least two spaced belts for feeding said continuous paper.

65. A mechanism in accordance with claim 63, wherein said roller comprises a locking roller which is adapted to engage two spaced rollers positioned on opposite side edges of said paper, in order to prevent said paper from moving during said predetermined non-printing periods.

66. A mechanism in accordance with claim 65, wherein said locking rollers is movable into a second position, spaced from said paper, to permit said paper to be fed.

67. A mechanism in accordance with claim 63, wherein said roller is connected to a heating roller forming part of said image fixing unit.

68. A mechanism in accordance with claim 67, wherein said roller is attached to said heating roller by a pivotable holder.

69. A mechanism in accordance with claim 63, said roller comprising a locking roller, said mechanism further comprising two additional spaced rollers which are adapted to be attached to said printer above a paper feeding path, said locking roller being positioned below said paper feeding path, wherein said path is positioned between said spaced apart rollers and said locking roller.

71. A mechanism in accordance with claim 63, said fixing unit comprising a holder attached to a heater roller, said holder being adapted to move said heating roller between a retracted position during at least said predetermined periods, and an actuated position during said printing periods, said roller being attached to said holder.

72. A mechanism in accordance with claim 71, wherein said holder comprises means for simultaneously retracting said heat roller and moving said roller into a locking position to prevent said paper from moving during said predetermined non-printing periods.

73. A mechanism in accordance with claim 72, said simultaneously moving and retracting means further comprising means for simultaneously moving said heating roller into a fixing position and said roller into a release position in order to permit movement of said paper.

74. A mechanism in accordance with claim 27, wherein said movement preventing means comprises at least one locking pin which is adapted to engage holes in said paper.

75. A mechanism in accordance with claim 74, comprising two spaced apart locking pins which are adapted to engage holes on opposite edges of said paper.

76. A mechanism in accordance with claim 75, wherein each of said locking pins projects upwardly from a pivotable arm which is attached to a roller positioned under said paper at a location spaced apart from said pins, as viewed in a direction along which said paper is adapted to travel through said printer.

77. A mechanism in accordance with claim 75, wherein each of said pins is attached to the end of a spring-biased arm which is movably connected to a heat roller in a fixing unit which forms part of said printer.

78. A mechanism in accordance with claim 75, wherein said pins do not engage holes on said paper during said printing periods, and engage said holes during said predetermined non-printing periods.

79. A mechanism in accordance with claim 74, further comprising a plurality of rollers positioned above and below a path along which said paper is adapted to be fed through said printer.

80. A mechanism in accordance with claim 79, said rollers including two spaced, loosely rotatable rollers positioned above said path, a dislocation roller positioned above said path and between said spaced loosely rotatable rollers, and a sensor roller positioned below said path and adjacent to said dislocation roller.

81. A mechanism in accordance with claim 74, wherein each said pin is vertically moveable in order to selectively engage holes on said paper.

82. A mechanism in accordance with claim 81, each said pin being positioned on an upper surface of a vertically slidable member, said printer including at least one belt assembly for feeding said paper through said printer, wherein said belt assembly and said slidable member include complementary engaging surfaces.

83. A mechanism in accordance with claim 82, wherein there are two pins, said printer further comprising an actuation shaft engaging the slidable members attached to said pins in order to move said pins in unison.

84. A mechanism in accordance with claim 83, wherein said actuation shaft has opposed first and second ends, each of said ends being connected to a pivotable lever.

85. A mechanism in accordance with claim 81, wherein each pin is moveable into a lower position in which it does not engage holes in said paper, and into an upper position in which it engages said holes to prevent said paper from moving during said predetermined non-printing periods.

86. A mechanism in accordance with claim 27, in combination with said printer, said printer including means for feeding said paper through said printer, and means for controlling movement of said paper during said printing periods and during certain non-printing periods.

87. A mechanism in accordance with claim 86, wherein said printer is an electrophotographic printer including an image transfer unit and an image fixing unit which are spaced from each other.

70. A mechanism in accordance with clam 69, wherein said locking roller has a length substantially equal to the width of said paper, said locking roller having opposite ends which are attached to a support arm which is adapted to be pivotally supported, via a shaft, to said printer.

88. A printer comprising an imaging fixing unit, and image transfer unit, means for feeding continuous form paper through said printer, means for controlling feeding of said paper during non-printing periods and during printing periods, and means for preventing movement of said paper during at least some of said non-printing periods, said preventing means comprising means for applying a load to said paper for preventing movement of said continuous form paper, said preventing means prevents movement of the continuous form paper when a fixing roll is separated from the continuous form paper.

89. A printer in accordance with claim 88, wherein said movement controlling means comprises a one-way clutch which is selectively engaged with a shaft which forms part of said feeding means.

90. A printer in accordance with claim 88, wherein said movement controlling means comprises a movable lever which is adapted to engage said feeding means in order to prevent movement of said paper.

91. A printer in accordance with claim 88, wherein said movement prevention means comprises a pair of rollers which are part of said image fixing unit.

92. A printer in accordance with claim 88, wherein said movement prevention means comprises at least one roller positioned between said paper feeding means and said image fixing unit.

93. A printer in accordance with claim 88, wherein said movement preventing means comprises at least one locking pin which is adapted to move between a position in which each said pin engages holes on said paper to prevent if from moving, and a position in which each said pin does not engage said holes.