JP2007131400A - Sheet supply device and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet supply device capable of enhancing separation effects of sheets by changing an air blowing condition without using a power source such as a motor. <P>SOLUTION: The sheet supply device is provided with a sheet storing tray 17 for storing sheets; an air blowing part 19 for blowing air to end parts of the sheets stored in the sheet storing tray 17; and an air variable means for varying the air blowing condition by the air blowing part 19. The air blowing part 19 has a blower 24 generating air and a duct 26 forming a flow path of the air generated by the blower 24. The air variable means has a rotating body 30 rotated inside the duct 26 by receiving the air from the blower 24 and a shutter member 29 changing the air blowing condition by being lifted/lowered by the rotating force of the rotating body 30. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet feeding apparatus suitable for application to an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a multifunction machine.

  In recent years, along with the diversification of recording media, in addition to sheets other than plain paper, such as thick paper, OHP sheets, tracing paper, etc., whiteness and gloss have been added to the surface of the sheets in order to meet the market demand for colorization. Opportunities are increasing to form images on sheets such as coated paper and glossy paper that have been subjected to a coating process for the purpose of printing. Of these, OHP sheets, tracing paper, coated paper, and glossy paper have higher sheet surface smoothness than plain paper, so that when sheets are stacked on top of one another, they adhere between the sheets. Power is greater than plain paper.

  In general, in an image forming apparatus such as a copying machine or a printer, sheets stored in a tray are separated and conveyed one by one. However, when the adhesion between the sheets stacked on the tray increases, Separation deteriorates. As a result, when feeding sheets from the tray, misfeeds such as double feeding in which a plurality of sheets are overlapped and sheet conveyance delay are likely to occur. In particular, in an environment of high humidity, a greater adhesion force acts between the sheets, and therefore, it becomes a situation where double feed and misfeed are likely to occur.

  Therefore, in the prior art, for example, as shown in FIG. 9, the sheets 52 accommodated in the tray 51 are called by the pickup roll 53 in order from the top, and the called sheets 52 are rolled by the feed roll 54 and the retard roll 55. In a sheet feeding apparatus that feeds in a feeding direction Y, a technique for releasing the adhesion between sheets by blowing air (air flow) to the end of a sheet 52 accommodated in a tray 51 using a blower (blower) 56. Has been proposed. In addition, conventionally, a technique has also been proposed in which an opening for blowing air to the sheet (air blowing port) is opened and closed to change the state of the air blown to the sheet to enhance the sheet separation effect ( For example, see Patent Documents 1 and 2).

  FIG. 10 is a diagram showing an example of the prior art. In the figure, a shutter member 57 is provided in the vicinity of one end of the sheet 52 accommodated in the tray 51. The shutter member 57 opens and closes the opening 59 of the nozzle 58 drawn from the blower 56. A rack 60 is formed on the shutter member 57. A pinion 61 is engaged with the rack 60. The pinion 61 is attached to the output shaft (rotary shaft) of the motor 62.

  In the above configuration, when the pinion 61 is rotated by driving the motor 62, the shutter member 57 moves in the vertical direction according to the rotation amount and the rotation direction. Therefore, when the air generated by the blower 56 is blown to the side end portion of the sheet 52 through the opening 59 of the nozzle 58, the shutter member 57 is moved up and down by driving the motor 62, so that the air blowing position on the sheet 52 is set. Can be changed.

  That is, when the shutter member 57 is moved downward by driving the motor 62 from the state in which the opening 59 of the nozzle 58 is completely closed by the shutter member 57 (fully closed state), the opening 59 of the nozzle 58 gradually increases from the upper side accordingly. Therefore, the air blowing position on the sheet 52 gradually shifts downward. Further, when the shutter member 57 is moved upward by driving the motor 62 from the state in which the opening 59 of the nozzle 58 is fully opened, the opening 59 of the nozzle 58 is gradually closed from the lower side accordingly. The air blowing position gradually shifts upward.

Japanese Patent No. 2974345 JP-A-11-5543

  However, in the above prior art, a configuration is employed in which the shutter member 57 is operated using the driving force of the motor 62 in order to change the air blowing state on the sheet 52 accommodated in the tray 51. For this reason, there are problems such as an increase in cost, an increase in power consumption, and a need for a large mounting space.

  The present invention has been made to solve the above-described problems, and the object of the present invention is to improve the sheet separation effect by changing the air blowing state without using a power source such as a motor. It is an object of the present invention to provide a sheet feeding apparatus that can perform the above.

  The sheet supply device according to the present invention includes: a sheet storage unit that stores a sheet; an air spray unit that blows air to an end portion of the sheet stored in the sheet storage unit; and a state of air blowing by the air spray unit The air blowing means includes an air generating means for generating air and a duct for forming a flow path of the air generated by the air generating means. Has a rotating body that receives air from the air generating means in the duct and rotates, and an air control member that changes the air blowing state by operating with the rotational force of the rotating body.

  In the sheet supply apparatus according to the present invention, the rotating body rotates in response to the air from the air generating means in the duct that forms the flow path of the air generated by the air generating means. Since the air blowing state is changed by the operation of the air control member, the sheet separation effect can be enhanced without using a power source such as a motor.

  According to the sheet supply apparatus of the present invention, when the air is blown to the edge of the sheet by the air blowing unit to separate the sheet, the air blowing state is changed using the air force generated by the air generating unit. be able to. For this reason, the sheet separation effect can be enhanced without using a power source such as a motor.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram showing a configuration example of an image forming apparatus to which the present invention is applied. The illustrated image forming apparatus 1 includes a receiving unit 5 connected to an image reading device 2 and an external device (such as a personal computer) 3 via a communication line 4, and an image writing unit based on image data received by the receiving unit 5. 6, an image recording control unit 7 that controls 6, a drum-shaped image carrier (photosensitive drum) 8 on which an electrostatic latent image is written by the image writing unit 6, and a circumferential direction of the image carrier 8. A charging device 9, a developing device 10, and a cleaner 11, a transfer roll 12 that transfers a toner image formed on the image carrier 8 to a sheet, a fixing device 13 that fixes the toner image transferred to the sheet, A pair of a discharge roll 14 that discharges the sheet on which the toner image is fixed by the fixing device 13, a discharge tray 15 that receives the sheet discharged by the discharge roll 14, and the image carrier 8 and the transfer roll 12. A sheet conveying unit 16 that conveys a sheet toward a position (nip position), a plurality of sheet accommodating trays 17 that accommodate sheets used for image formation in a stacked state, and sheets accommodated in the sheet accommodating tray 17 A sheet supply unit 18 that supplies the sheet to the sheet conveying unit 16 and an air blowing unit 19 that blows air (air flow) onto the sheets stored in the sheet storage tray 17 are provided. The image reading device 2 may exist as one functional unit of the image forming apparatus 1 or may exist as a functional unit separate from the image forming apparatus 1.

  FIG. 2 is a schematic diagram illustrating a configuration example of a sheet feeding apparatus to which the present invention is applied. The sheet supply unit 18 is disposed on the front side of the sheet storage tray 17 (the side where the sheet is fed out). The sheet supply unit 18 includes a pickup roll 20, a feed roll 21, and a retard roll 22. The sheet supply unit 18 supplies the sheets 23 stored in a stacked state on the sheet storage tray 17 in order from the uppermost sheet. In the sheet storage tray 17, the height position of the uppermost sheet is held at a substantially constant position by, for example, a known elevator system, one-side lifting system, spring lifting system, or the like.

  The pickup roll 20 abuts on the uppermost surface of the sheet 23 accommodated in the sheet accommodation tray 17 with a predetermined pressing force, and rotates in the direction of the arrow in the abutting state to remove the sheet 23 from the sheet accommodation tray 17. It is what you call. The feed roll 21 rotates in the direction of the arrow in the drawing to feed the sheet 23 called by the pickup roll 20 toward the sheet conveying unit 16 while being nipped with the retard roll 22. The retard roll 21 comes into contact with the lower surface side of the sheet 23 called between the feed roll 21 (nip position) by the pickup roll 20 and gives a frictional resistance to the lower surface sheet in this contact state. This prevents double feeding of sheets. In addition to the retard roll method, for example, a separation claw method or a vacuum feed method may be employed as the configuration of the sheet supply unit 18.

  The air blowing unit 19 is disposed in a state of facing one side of the sheet storage tray 17. The air blowing unit 19 blows air between the upper and lower overlapping sheets by blowing air to the side end portion of the sheet 23 stored in the sheet storage tray 17 to release the adhesion between the sheets. To separate. The side end portion of the sheet 23 refers to an end portion of the sheet 23 that is arranged in the sheet storage tray 17 in a direction orthogonal to the sheet supply direction Y. The sheet supply direction Y is a direction in which the sheet 23 moves when the sheet supply unit 18 supplies the sheet 23 from the sheet storage tray 17.

  FIG. 3 is a diagram showing the configuration of the air blowing unit according to the first embodiment of the present invention. In the configuration of the air blowing unit 19 shown in the figure, a blower 24 using a sirocco fan or the like that generates air by rotation is used as air generating means, and air is blown out from the blower 24 in a substantially horizontal direction. The blower 24 is provided with an air intake port 25. A cylindrical duct 26 having a square cross section is drawn from the blower 24. The duct 26 is connected to the blower 24 in order to form a flow path for the air generated by the blower 24.

  A nozzle 27 is provided at an end portion (exit portion) of the duct 26. The nozzle 27 forms one side wall portion of the sheet storage tray 17 and has an opening (air blowing port) 28 for blowing air generated by the blower 24 to the side end portion of the sheet 23 through the duct 26. is there. The nozzle 27 is configured using a pair of plate members 27A and a frame member 27B. In the pair of plate members 27A, rectangular openings 28 having the same size and the same size are formed. The frame member 27B couples the pair of plate members 27A while being sandwiched between the pair of plate members 27A. Further, the plate member 27A is arranged in an opposing state with the thickness dimension of the frame member 27B.

  A shutter member 29 serving as an air control member is inserted inside the nozzle 27 (between the pair of plate members 27A). The shutter member 29 has a flat plate shape as a whole, and is inserted between the pair of plate members 27A constituting the nozzle 27 from below. Spacers for avoiding contact between the shutter member 29 and the nozzle 27 and for smooth movement of the shutter member 29 are interposed in the facing portion (gap portion) of the shutter member 29 and the nozzle 27. The shutter member 29 opens and closes the opening 28 of the nozzle 27 by reciprocating (up and down movement) in the sheet stacking direction (up and down direction).

  On the other hand, a rotating body 30 is disposed inside the duct 26. The rotating body 30 includes a rotating shaft 31 having a circular cross section and a plurality of blades (blades) 32. The rotating shaft 31 is stretched horizontally in a direction orthogonal to the direction of the air flowing through the duct 26. Each blade 32 is attached around the rotating shaft 31 at a predetermined angular pitch. The blade 32 is formed wide in the axial direction of the rotary shaft 31. The rotating body 30 is disposed on a flow path of air blown out from the blower 24, and receives air from the blower 24 by the blade 32 and rotates in one direction. The rotating direction of the rotating body 30 when receiving air from the blower 24 may be either clockwise or counterclockwise as long as it always rotates in one direction.

  4A and 4B show the configuration of the motion conversion means employed in the first embodiment of the present invention. FIG. 4A is a view as seen from the sheet supply direction, and FIG. 4B is a GG cross-sectional view of FIG. . The operation converting means converts the rotating operation of the rotating body 30 into the operation of the shutter member 29 (in this example, the lifting operation). As shown in the drawing, both end portions of the rotating shaft 31 of the rotating body 30 project outward (outside the duct) in such a manner as to penetrate the side wall portion of the duct 26, and link arms 33 are attached to the projecting portions. The base end portion of the link arm 33 is fitted and fixed to the end portion of the rotating shaft 31. Further, an engagement pin 34 is provided at the distal end portion (free end) of the link arm 33. As a result, when the rotating shaft 31 rotates, the link arm 33 turns together with the rotating shaft 31 around the rotating shaft 31 and the engaging pin 34 circulates around the rotating shaft 31.

  On the other hand, the shutter member 29 is supported in a vertical posture by a pair of support arms 35. Each support arm 35 can be formed integrally with the shutter member 29. It is also possible to fix one end of each support arm 35 to the shutter member 29 using a screw or the like. A long hole 36 is formed at the other end of each support arm 35. The long axis of the long hole 36 is horizontally arranged in a direction perpendicular to the axial direction of the rotary shaft 31. The longitudinal dimension of the long hole 36 is set to be approximately twice the length of the link arm 33. The short dimension of the long hole 36 is set to be slightly larger than the diameter of the engagement pin 34 described above. Then, the engagement pins 34 of the link arm 33 are engaged (inserted) into the long holes 36 of the respective support arms 35.

  Next, the operation of the sheet feeding apparatus provided with the air blowing unit 19 having the above configuration will be described. First, when the sheet 23 stored in the sheet storage tray 17 is supplied by the sheet supply unit 18, the uppermost surface of the sheet 23 is arranged at a predetermined height in the sheet storage tray 17, and in this state, the uppermost sheet 23 is placed. The pickup roll 20 is brought into contact with the upper surface and rotated. Accordingly, the uppermost sheet 23 is called from the sheet storage tray 17 in the sheet supply direction Y according to the rotation of the pickup roll 20. The sheet 23 called in this way is nipped between the feed roll 21 and the retard roll 22 and then sent downstream in the sheet feeding direction Y according to the rotation of the feed roll 21.

  In such a sheet feeding operation, when air is blown from the air blowing unit 19 to the side edge of the sheet 23, the close contact between the sheets is released by the flow of air between the sheets. For this reason, the sheets are separated between the sheets into which the air has flowed. Accordingly, the sheet 23 can be sent out while being rolled one by one by the feed roll 21 and the retard roll 22. At that time, in order to flow the air blown by the air blowing unit 19 more reliably between the sheets, it is effective to change the air blowing state with respect to the sheet 23 stored in the sheet storage tray 17.

  Therefore, in the first embodiment of the present invention, the air blowing state can be changed by the following operation. That is, when the air generated by the blower 24 flows through the duct 26, the rotating body 30 rotates by receiving this air. Then, the link arm 33 attached to both ends of the rotating shaft 31 turns, and the engaging pin 34 provided at the tip of the link arm 33 engages with the long hole 36 of the support arm 35 while rotating the rotating shaft 31. Orbit around. As a result, the support arm 35 moves up and down integrally with the shutter member 29 in conjunction with the turning of the link arm 33 (up and down operation).

  At this time, when the engagement pin 34 is at the highest position on the orbit of the engagement pin 34, the opening 28 of the nozzle 27 is fully closed by the shutter member 29, and the engagement pin 34 is at the lowest position. When present, the opening 28 of the nozzle 27 is fully opened by the shutter member 29. For this reason, when the link arm 33 pivots integrally with the rotary shaft 31 and the shutter member 29 moves up and down in conjunction with this, the opening 28 of the nozzle 27 is repeatedly opened and closed by the shutter member 29. Therefore, the air blowing position on the sheet 23 can be continuously changed in the sheet stacking direction (vertical direction).

  That is, when the shutter member 29 moves downward as the link arm 33 turns from a state in which the opening 28 of the nozzle 27 is fully closed by the shutter member 29 (a state in which the engagement pin 34 is at the highest position), the nozzle 27 Are gradually opened from above. For this reason, the air blowing position on the sheet 23 gradually shifts (expands) downward. Further, when the shutter member 29 moves upward as the link arm 33 turns from a state in which the opening 28 of the nozzle 27 is fully opened by the shutter member 29 (a state in which the engagement pin 34 is present at the lowest position), The opening 28 is gradually closed from the lower side. For this reason, the air blowing position on the sheet 23 gradually shifts (reduces) downward.

  In this way, by changing the air blowing position by the shutter member 29 in the sheet stacking direction (vertical direction), it is possible to intermittently blow air to the position where the sheet is to be separated (upper layer sheet). Further, the air flow between the sheets is most likely to occur at the moment when air is blown onto the sheets. For this reason, the opportunity for air to flow between sheets can be increased by changing the air blowing position. Therefore, the sheets can be more reliably separated than when air is always blown to the same position. Further, the rotating body 30 is rotated by the air force (wind power) generated by the blower 24, and the shutter member 29 is moved up and down by using this rotational force, thereby opening and closing the opening 28 of the nozzle 27 to open and close the air. Since the spraying state (the spraying position in this embodiment) is changed, it is not necessary to provide a separate drive source such as a motor. For this reason, cost reduction, power saving, and space saving of the sheet supply apparatus can be achieved.

  Further, as shown in FIG. 5, if the shutter member 29 is provided with a horizontally long slit-shaped small window (ventilation window) 29 </ b> A, the opening 28 of the nozzle 27 is fully closed by the shutter member 29. When the shutter member 29 is moved downward, the opportunity to separate the sheets by blowing air increases. That is, when the shutter member 29 is moved downward from the state in which the opening 28 of the nozzle 27 is fully closed, air is first blown to the upper sheet 23 through the small window 29A, and then the small window 29 is moved downward. After the air blowing to the upper sheet 23 stops, the air is again blown onto the upper sheet 23. For this reason, when the shutter member 29 is moved up and down, the opportunity to separate the sheets can be increased.

  FIG. 6 is a diagram showing a configuration of an air blowing unit according to the second embodiment of the present invention. FIG. 7 is a view of the configuration of the motion conversion means employed in the second embodiment of the present invention as seen from the sheet supply direction. In the second embodiment, the same components as those in the first embodiment will be described with the same reference numerals.

  6 and 7, the speed reduction mechanism 37 is used as a transmission unit that transmits the rotational force of the rotating body 30 to the shutter member 29. The reduction mechanism 37 is configured by a gear train in which a plurality (six in the illustrated example) of gears (spur gears) 38 to 43 are engaged with each other. The gear 38 rotates integrally with the rotating shaft 31 of the rotating body 30, and is fitted and fixed coaxially to one end of the rotating shaft 31. The gear 38 meshes with a gear 39 having a diameter larger than that of the gear 38. The gear 39 is coaxially fitted and fixed to a support shaft 44 common to the gear 40 having a smaller diameter than the gear 39. The gear 40 meshes with a gear 41 having a diameter larger than that of the gear 40. The gear 41 is coaxially fitted and fixed to a support shaft 45 common to the gear 42 having a smaller diameter than the gear 41. The gear 42 meshes with a gear 43 having a diameter larger than that of the gear 42. The gear 43 is fitted and fixed to one end side of the support shaft 46. It should be noted that the gears 34 and 40 and the gears 41 and 42 may be configured as stepped gears formed integrally.

  The support shafts 44, 45, 46 are all arranged in parallel with the rotation shaft 31 of the rotating body 30. Each of the support shafts 44, 45, and 46 is rotatably provided using a bearing member (not shown). The support shafts 44 and 45 are disposed so as to protrude outward from the side wall portion of the duct 26. The support shaft 46 is supported by a pair of support members 47 provided on both sides of the lower surface portion of the duct 26. Link arms 48 are attached to both ends of the support shaft 46, respectively. The base end portion of the link arm 48 is fitted and fixed to the end portion of the support shaft 46. Further, an engagement pin 49 is provided at the distal end portion (free end) of the link arm 48.

  On the other hand, the shutter member 29 is supported in a vertical posture by a pair of support arms 35. Each support arm 35 can be formed integrally with the shutter member 29. It is also possible to fix one end of each support arm 35 to the shutter member 29 using a screw or the like. A long hole 36 is formed at the other end of each support arm 35. The long axis of the long hole 36 is horizontally arranged in a direction perpendicular to the axial direction of the rotary shaft 31. The longitudinal dimension of the long hole 36 is set to be approximately twice the length of the link arm 48. The short dimension of the long hole 36 is set to be slightly larger than the diameter of the engagement pin 49 described above. Then, the engagement pin 49 of the link arm 48 is engaged with the long hole 36 of each support arm 35.

  One support arm 35 is provided with a detection piece 50. The detection piece 50 is integrated with the shutter member 29 and moves (lifts) in the vertical direction. For this reason, the detection piece 50 may be formed integrally with the support arm 35 or may be attached to the support arm 35 using a screw or the like. A photo sensor 51 is arranged in the middle of the movement path of the detection piece 50. The photosensor 51 is composed of, for example, a transmissive photointerrupter having a light emitting element and a light receiving element. The photosensor 51 is turned off when light from the light emitting element is received by the light receiving element. When the optical path is blocked by the detection piece 50, it is turned on.

  In the air blowing unit 19 according to the second embodiment, when the rotating body 30 (the rotating shaft 31) rotates by receiving air from the blower 24, the rotational force is transmitted by the plurality of gears 38 to 43. The support shafts 44, 45, 46 rotate. When the support shaft 46 rotates, the link arm 48 turns integrally with the support shaft 46 and the engaging pin 49 circulates around the support shaft 46. As a result, the support arm 35 moves up and down integrally with the shutter member 29 (lifting operation) in conjunction with the turning of the link arm 48. As a result, the opening 28 of the nozzle 27 is repeatedly opened and closed by the shutter member 29. Therefore, similarly to the first embodiment, the air blowing state can be changed without using a drive source such as a motor.

Further, in the second embodiment, as the configuration of the operation conversion means, the speed reduction mechanism 37 formed of a gear train is employed in the transmission mechanism portion that transmits the rotational force of the rotating body 30 to the shutter member 29. The shutter member 29 can be moved in the vertical direction by rotating the support shaft 46 at a lower speed without depending on the rotation speed of 30 (the number of rotations per unit time). Therefore, the shutter member 29 can be moved up and down at a desired speed by appropriately setting the reduction ratio of the speed reduction mechanism 37.
By adopting this configuration, it is possible to reduce the rotational force (rotational torque) of the rotating body 30 necessary for moving the shutter member 29 up and down as compared to the first embodiment, and to reduce the reduction ratio. The moving speed of the shutter can be adjusted by setting.

  If the operation of the sheet supply apparatus is controlled by a sheet supply control unit (control means) (not shown), the sheet supply control unit controls the drive stop timing of the blower 24 based on the timing chart shown in FIG. In FIG. 8, a sheet supply signal is a pulse signal transmitted from an image forming control unit (not shown) to instruct sheet supply to the sheet supply control unit. Therefore, each time a sheet supply signal is output, the sheet 23 is supplied from the sheet storage tray 17 by driving the sheet supply unit 18.

  The sensor signal is a signal output from the photosensor 51. This sensor signal is turned off when the light from the light emitting element constituting the photosensor 51 is received by the light receiving element as described above, and the optical path between the light emitting element and the light receiving element is blocked by the detection piece 50. Sometimes it turns on. The photosensor 51 is a sensor that detects that the shutter member 29 has reached a predetermined operating position. Therefore, for example, when the position immediately before the opening 28 of the nozzle 27 is completely closed by the shutter member 29 in the process of moving (raising) the shutter member 29 upward is set as a predetermined operation position, the shutter is moved to the operation position. When the member 29 arrives, the optical path of the photosensor 51 is blocked by the detection piece 50.

  The blower drive signal is a drive signal output from the sheet supply control unit in order to drive the blower 24. When the blower drive signal is on, the fan of the blower 24 is rotated, and when the blower drive signal is off, the fan of the blower 24 is stopped. Therefore, the drive stop timing of the blower 24 means a timing at which the blower drive signal is switched from the on state to the off state.

  Whenever the sheet supply control unit receives a sheet supply signal from an image formation control unit (not shown), the sheet supply control unit 18 drives the sheet supply unit 18 to supply one sheet 23, and the sheet supply signal falls timing (or rises). Time measurement starts with a timer from the timing. If the next sheet supply signal is received before the measured value of the timer exceeds a preset value T1 (sec), the sheet 23 is supplied in the same manner as described above, and the timer value is reset. To do.

  On the other hand, when the measured value of the timer exceeds the predetermined value T1 (sec) without receiving the next sheet supply signal, monitoring of the sensor signal is started from that point, and the sensor signal is turned off. Timing of switching to the ON state (in other words, timing when the shutter member 29 reaches a predetermined operation position) is detected. Then, the timer starts measuring time again from this detection timing, and the blower drive signal is switched from the on state to the off state when the measured value of the timer reaches a predetermined value T2 (msec) set in advance.

  By controlling the drive stop timing of the blower 24 in this manner, the drive of the blower 24 is always stopped immediately after the shutter member 29 reaches the predetermined operating position (after T2 msec). Therefore, when stopping the driving of the blower 24, the shutter member 29 can be stopped at substantially the same position. Therefore, each time the sheet supply is resumed, the shutter member 29 can be operated from the same position. In addition, as described above, the position immediately before the opening 28 of the nozzle 27 is completely closed by the shutter member 29, the moment when it is completely closed, or the position immediately after it is completely closed is set as the “predetermined operation position”. Thus, each time the sheet supply is resumed, the shutter member 29 can be operated from the state in which the opening 28 of the nozzle 27 is closed by the shutter member 29 (preferably the state in which it is fully closed). A similar configuration / control can be realized by the configuration of the first embodiment.

  In the above-described embodiment, an example has been described in which air is blown to the side end portion of the sheet 23 stored in the sheet storage tray 17, but the present invention is not limited to this, for example, although not illustrated. A device that blows air to the front end of the sheet 23 stored in the sheet storage tray 17 (the end of the sheet disposed facing the downstream side in the sheet supply direction Y) or the sheet 23 stored in the sheet storage tray 17 The invention can be similarly applied even when air is blown to the rear end portion (the end portion of the sheet disposed facing the upstream side in the sheet supply direction Y).

1 is a schematic diagram illustrating a configuration example of an image forming apparatus to which the present invention is applied. It is the schematic which shows the structural example of the sheet supply apparatus with which this invention is applied. It is a figure which shows the structure of the air spraying part which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of the operation | movement conversion means employ | adopted in 1st Embodiment of this invention. It is a figure which shows the other structure of a shutter member. It is a figure which shows the structure of the air spraying part which concerns on 2nd Embodiment of this invention. It is the figure which looked at the structure of the operation | movement conversion means employ | adopted by 2nd Embodiment of this invention from the sheet supply direction. 6 is a timing chart applied during sheet supply control. It is the schematic which shows the structural example of the conventional sheet supply apparatus. It is a figure which shows an example of a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 17 ... Sheet storage tray, 18 ... Sheet supply part, 19 ... Air spraying part, 20 ... Pickup roll, 21 ... Feed roll, 22 ... Retard roll, 23 ... Sheet, 24 ... Blower, 26 ... Duct 27 ... Nozzle, 28 ... Opening, 29 ... Shutter member, 30 ... Rotating body, 37 ... Reduction mechanism

Claims (6)

Sheet supply comprising: sheet storing means for storing a sheet; air blowing means for blowing air to an end portion of the sheet stored in the sheet storing means; and air variable means for changing the air blowing state by the air blowing means. A device,
The air blowing means has air generating means for generating air, and a duct for forming a flow path of air generated by the air generating means,
The air variable means includes: a rotating body that rotates by receiving air from the air generating means in the duct; and an air control member that changes a blowing state of the air by operating by a rotational force of the rotating body. A sheet supply apparatus comprising: The air blowing means is connected to the duct and has a nozzle at the outlet of the duct.
The sheet supply apparatus according to claim 1, wherein the air control member includes a shutter member that opens and closes an opening of the nozzle. The sheet supply apparatus according to claim 1, further comprising an operation conversion unit that converts a rotation operation of the rotating body into an operation of the air control member. The sheet feeding apparatus according to claim 3, wherein the motion conversion unit includes a speed reduction mechanism. Detecting means for detecting that the air control member has reached a predetermined operating position;
The sheet feeding apparatus according to claim 1, further comprising: a control unit that controls a drive stop timing of the air generation unit based on a detection result of the detection unit. Sheet supply comprising: sheet storing means for storing a sheet; air blowing means for blowing air to an end portion of the sheet stored in the sheet storing means; and air variable means for changing the air blowing state by the air blowing means. An image forming apparatus comprising the device,
The air blowing means has air generating means for generating air, and a duct for forming a flow path of air generated by the air generating means,
The air variable means includes: a rotating body that rotates by receiving air from the air generating means in the duct; and an air control member that changes a blowing state of the air by operating by a rotational force of the rotating body. An image forming apparatus comprising:

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