JP2006021851A - Paper feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeding device capable of allowing paper dust to be hardly deposited inside and around the paper feeding device and eliminating a factor of causing turbulence of an image by collecting paper dust stirred up in the paper feeding device. <P>SOLUTION: When air is blown to a recording paper P from an air blowing device 74, paper dust deposited on an edge part or the like of the recording paper P is stirred up in a storage frame 52, and air containing paper dust is sucked by a fan 80. Thus, paper dust is not deposited inside or around the paper feeding device 40, preventing deposited paper dust from being dropped on the recording paper P, and conveyed to an image forming unit together with the recording paper P to cause troubles in forming an image. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a paper feeding device used in an image forming apparatus such as a copying machine or a printer.

  As shown in FIG. 8, air is blown to the side of the sheet P from the air exhaust port 108 of the fan 102, and the air is passed between the sheets P, so that the topmost sheet becomes the other sheet P. A method of separating and transporting the sheet has been proposed (see Patent Document 1).

However, when air is blown onto the sheet P, the paper dust adhering to the edge portion of the sheet P may rise, and may accumulate or adhere to the inner wall, the peripheral portion, the opening / closing cover 104 and the like of the sheet feeding device 100. The accumulated and adhering paper powder may fall on the sheet P stored in the paper feed tray 106 due to an impact when the opening / closing cover 104 is opened and closed. In addition, paper dust that has accumulated and adhered to the opening / closing cover 104 and the inner wall of the paper feeding device 100 also falls on the sheet due to an impact when the paper feeding tray 106 is taken in and out of the image forming apparatus. When the sheet P on which the paper dust is placed is conveyed to the image forming unit, the image is disturbed in the image forming process, which causes image disturbance.
JP 2003-63675 A

  In view of the above facts, the present invention collects paper dust that has risen in the paper feeding device, thereby making it difficult for paper dust to accumulate inside and around the paper feeding device, and to eliminate factors that cause image disturbance. And

  The invention according to claim 1 is a sheet storage unit that stores a sheet, a sheet supply member that feeds out a sheet stored in the sheet storage unit, and an air blowing device that blows air onto the sheet stored in the sheet storage unit And a paper dust suction means for sucking paper dust.

  According to the first aspect of the present invention, when air is blown from the air blowing device to the sheet, the paper dust adhering to the edge portion of the sheet soars into the paper feeding device, but the air containing the paper dust is Inhaled by paper dust suction means. For this reason, paper dust does not accumulate inside or around the paper feeder. Therefore, unlike the conventional case, the accumulated paper dust does not fall on the sheet and is transported to the image forming unit together with the sheet, and there is no possibility of hindering image formation.

  The invention according to claim 2 is characterized in that the paper dust suction port of the paper dust suction means is provided at a position where the uppermost sheet of the sheet is not sucked.

  According to the second aspect of the present invention, by providing the suction port of the suction unit at a position where the uppermost sheet is not sucked in the vertical direction, the uppermost sheet is vertically aligned by the negative pressure generated from the paper dust suction unit. And is smoothly conveyed to the image forming unit.

  The invention according to claim 3 is characterized in that the paper powder suction port is provided above the uppermost sheet.

  According to the third aspect of the present invention, the paper dust attached to the sheet flies above the uppermost sheet when air is blown, so that the uppermost sheet where paper dust is most abundant. By providing the paper dust suction port, the paper dust can be sucked more easily.

  The invention according to claim 4 is characterized in that the paper dust suction port is provided below the sheet storage portion.

  According to the fourth aspect of the present invention, the uppermost sheet is generated from the paper dust suction means when air is blown from the air blowing device to the sheet by providing the paper dust suction port below the sheet storage portion. Without being pulled by the negative pressure, it is smoothly conveyed to the image forming unit.

  The invention according to claim 5 is characterized in that an air filter is provided in the paper powder suction port.

  According to the invention described in claim 5, by providing an air filter in the paper dust suction port, when the air in the paper feeding device is exhausted to the outside, the paper dust in the air is removed by the air filter, Air that does not contain paper dust is exhausted to the outside of the paper feeder. Therefore, by exhausting the air in the paper feeding device to the outside of the paper feeding device, paper dust does not adhere to the outside of the paper feeding device and peripheral equipment.

  The invention described in claim 6 is characterized in that the air spray device generates a negative pressure at the paper powder suction port of the paper powder suction means.

  According to the sixth aspect of the present invention, an air spraying device is used as means for generating a negative pressure at the paper powder suction port of the paper powder suction means. As a result, there is no need to arrange a blower or a fan in each of the air blowing means and the paper dust suction means, which leads to downsizing of the paper feeding device and saving of power consumption.

  With the above configuration, the present invention collects paper dust that has risen in the paper feeding device, thereby making it difficult for paper dust to accumulate in and around the paper feeding device, and eliminating factors that cause image disturbance.

  Before describing the sheet feeding device 40 according to the first embodiment of the present invention, an outline of the image forming apparatus 10 including the sheet feeding device 40 will be described.

  As shown in FIG. 1, the image forming apparatus 10 includes an image forming unit 12. The image forming unit 12 is provided with a photosensitive drum 14, and a charger 16, a developing device 18, and a cleaner 20 are disposed in the circumferential direction of the photosensitive drum 14. An image writing device 22 that irradiates the surface of the photosensitive drum 14 with laser light is provided between the charger 16 and the developing device 18.

  The image writing device 22 is connected to the image recording control unit 24. The image recording control unit 24 is connected to the receiving unit 26 via the communication line 32, and image information such as data read by the image reading device 28 or data from an external device (such as a personal computer) 30 is received. The image is sent from the receiving unit 26 to the image recording control unit 24. Then, the laser light is modulated based on the image information controlled by the image recording control unit 24, and an electrostatic latent image is formed on the photosensitive drum 14 from the image writing device 22.

  The surface of the photosensitive drum 14 is charged to a predetermined potential by the charger 16. Then, laser light is irradiated from the image writing device 22 to expose the surface of the photosensitive drum 14 to form an electrostatic latent image. This electrostatic latent image is developed by the developing device 18 and a toner image is formed on the surface of the photosensitive drum 14. At this time, the toner remaining on the surface of the photosensitive drum 14 without being transferred to the recording paper P is collected by the cleaner 20.

  A transfer roller 34 is provided on the opposite side of the photosensitive drum 14 from the image writing device 22 so as to face the photosensitive drum 14. A toner image on the photosensitive drum 14 is transferred by a transfer roller 34 to a recording sheet P conveyed from a paper supply unit 42 described later, and the toner image is recorded on the recording sheet P by a fixing device 36 installed downstream in the conveying direction. To be established. Then, the recording paper P is discharged to a discharge tray 39 by a pair of discharge rollers 38 provided on the downstream side in the transport direction of the fixing device 36.

  On the other hand, below the image forming apparatus 10, a paper feeding unit 42 in which a plurality of paper feeding devices 40 are provided up and down is disposed.

  FIG. 2 is a cross-sectional view of the paper feed tray 44 as viewed from the back of the storage frame 52 described later. As shown in FIG. 2, the paper feeding device 40 includes a rectangular paper feeding tray 44. The recording paper P is stacked in the paper feed tray 44, and an end guide 48 for regulating the rear end surface of the recording paper P in the transport direction is provided on the upstream side in the transport direction. One end face (side end face) in a direction orthogonal to the conveyance direction of the recording paper P is abutted against the side wall 44C of the paper feed tray 44, and the other side of the recording paper P is located at a position facing the side wall 44C. A side guide 50 is installed to regulate the side end face of the first side. The end guide 48 is slidable in the transport direction and the side guide 50 is slidable in the direction perpendicular to the transport direction, and the end guide 48 is slid according to the size of the recording paper P to position the end surface of the recording paper P. ing.

  As shown in FIG. 3, a bottom plate 47 that moves up and down by driving a motor (not shown) is provided at the bottom of the paper feed tray 44. The motor is turned on and off by a micro switch. When the uppermost height of the recording paper P becomes lower than a predetermined height and the microswitch is turned on, the motor is driven to raise the bottom plate 47. When the uppermost height of the recording paper P reaches a predetermined height and the microswitch is turned off, the driving of the motor is stopped and the ascent of the bottom plate 47 is stopped.

  As shown in FIG. 2, the paper feed tray 44 is accommodated in an accommodation frame 52 provided in the main body of the image forming apparatus 10 (see FIG. 1). An opening 54 is formed in the front side wall (side wall parallel to the transport direction) of the storage frame 52 in the drawing, and the paper feed tray 44 can be pulled out from the opening 54 to the front side.

  A drawer rail 56 is provided on the inner side of the side wall 52 </ b> A parallel to the direction orthogonal to the conveying direction of the storage frame 52. A rail portion 58 provided on a side wall 44 </ b> A in the transport direction of the paper feed tray 44 is engaged with the pull-out rail 56, and the paper feed tray 44 transports the recording paper P to the storage frame 52. It slides in a direction perpendicular to the direction.

  A gripping portion 60 is formed on the side wall 44B parallel to the conveyance direction of the paper feed tray 44. When the paper feed tray 44 is stored in the storage frame 52, the gripping portion 60 is gripped and brought to the front. When pulled out, the paper feed tray 44 is pulled out from the storage frame 52.

  An opening 64 having a size through which the recording paper P can pass is formed in the side wall 52A on the front end side in the conveyance direction of the recording paper P of the storage frame 52. A roll unit 66 is provided in the vicinity of the opening 64.

  The roll unit 66 is swingable via a support arm (not shown), contacts a top surface of the recording paper P loaded on the paper feed tray 44, and feeds the recording paper P. A feed roll 70 installed on the downstream side of the roll 68 and for feeding the recording paper P fed from the nudger roll 68 to the downstream side, and disposed below the feed roll 70, pressing the feed roll 70 A retard roll 72 is provided for separating the recording paper P and conveying it to the image forming unit.

  An air outlet 76 of the air blowing device 74 is installed on the side wall 52 </ b> C facing the opening 54 of the housing frame 52. A blower 77 is connected to the suction port side of the air blowing device 74, and the air blown from the blower 77 is blown out toward the recording paper P from the air blowout port 76.

  As shown in FIG. 3, the air outlet 76 is disposed closer to the downstream side in the transport direction. The lower end of the air outlet 76 is positioned below the uppermost recording sheet P, and the upper end is positioned above the uppermost recording sheet P. Thereby, the air blown out from the air blower outlet 76 is almost straight toward the downstream side end in the transport direction.

  In the present embodiment, the air blowing device 74 is provided on the side wall 52C (side wall parallel to the transport direction) facing the opening of the storage frame 52, so that the air is blown in the direction orthogonal to the transport direction of the recording paper P. However, the position where the air is blown may be the front end of the recording paper P. Further, the opening width of the air outlet 76 may be a part of the side of the recording paper P or may extend over the recording paper P. Furthermore, although the number of the air blowing devices 74 is one in this embodiment, it may be installed at a plurality of locations.

  As shown in FIGS. 2 and 3, a substantially rectangular air inlet 78 is formed in the top plate 52 </ b> B of the housing frame 52, and a fan 80 is attached to the air inlet 78. The fan 80 is connected to a driving device (not shown). By rotating the fan 80, the air inside the housing frame 52 is exhausted from the intake port 78 to the outside of the housing frame 52. A filter 82 is attached to the intake port 78. As a result, foreign matter such as paper dust contained in the air passing through the intake port 78 is captured by the filter 82.

  Next, the operation of the first embodiment of the present invention will be described.

  Paper dust adheres to the edge portion of the recording paper P stored in the paper feed tray 44, and when air is blown from the air blowing device 74 toward the edge portion of the recording paper P, the paper dust is blown off, It floats in the containing frame 52.

  Here, as shown in FIG. 3, by driving a fan 80 provided on the top plate 52 </ b> B of the housing frame 52, the air inside the housing frame 52 is sucked from the air inlet 78. As a result, paper dust drifting inside the storage frame 52 is captured by the filter 82, and the air from which the paper powder has been removed is exhausted to the outside of the storage frame 52. Accordingly, it is possible to prevent paper dust from accumulating in the paper feeding device 40 and its peripheral devices, so that the accumulated paper dust falls on the recording paper P and is transported to the image forming unit together with the recording paper P to form an image. There is no fear of formation.

  Further, since the paper dust adhering to the recording paper P flies above the uppermost recording paper P when air is blown, the fan 80 is placed above the uppermost recording paper P where the most paper dust is dancing. By attaching, it becomes easier to collect paper dust.

  Furthermore, since the paper dust contained in the air in the storage frame 52 is removed by the filter 82 provided in the intake port 78, even if the air inside the storage frame 52 is exhausted to the outside, the paper frame 52 The outside is not contaminated with paper dust.

  In the present embodiment, the filter 82 is provided in the intake port 78 of the fan 80. However, the filter 82 is not necessarily provided in the intake port 78.

  In the present embodiment, the air inlet 78 is formed in the top plate 52B of the housing frame 52 and the fan 80 is attached. However, the suction port of the duct is connected to the air inlet 78 and is opposite to the suction port of the duct. It is good also as a structure which attracts | sucks the air in the accommodation frame 52 from the suction opening of a duct by attaching a fan to this exhaust port and driving a fan. Further, although only one fan 80 is used, a plurality of fans 80 may be provided. Furthermore, it can also be set as the structure which attracts | sucks the air inside the accommodating frame 52 with a blower instead of a fan.

  Next, a paper feeding device 84 according to the second embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIG. 4, an intake port 86 is formed in the side wall 52 </ b> C of the housing frame 52, and a fan 88 is attached to the intake port 86. Then, the fan 88 is driven to exhaust the air in the housing frame 52 from the intake port 86 to the outside of the housing frame 52. Although not shown, a filter is attached to the intake port 86.

  Next, the operation of the second exemplary embodiment of the present invention will be described.

  As shown in FIG. 4, a fan 88 is attached to the side wall 52C of the storage frame 52, that is, a position where the uppermost recording sheet P is not sucked in the vertical direction with respect to the recording sheet P. The fan 88 is not pulled in the vertical direction by the negative pressure generated by driving the fan 88, and is smoothly conveyed to the image forming unit.

In this embodiment, the fan 88 is installed on the side wall 52C of the housing frame 52. However, as shown in FIG. 5, an air inlet 90 is formed on the bottom surface 52D of the housing frame 52, and The fan 92 may be attached. As a result, when the fan 92 is driven, the air in the housing frame 52 is directed to the intake port 90. Then, the paper dust contained in the air is removed by the filter 94 provided at the intake port 90 and is exhausted from the intake port 90 to the outside of the housing frame 52.

  Thus, even when the fan 92 is attached to the bottom surface 52D of the storage frame 52, the uppermost recording paper P is not pulled by the negative pressure generated by driving the fan 92, and the image forming unit smoothly It is conveyed to.

  Next, a paper feeder 150 according to a third embodiment of the present invention will be described. In addition, the description about the part similar to 1st Embodiment is omitted.

  As shown in FIGS. 6 and 7, a blowout duct 156 and a suction duct 152 are provided on the side wall 52 </ b> C of the storage frame 52.

  One opening of the duct 156 is an air outlet 162 and is attached to the side wall 52C. Further, an air outlet of the blower 158 is connected to the other opening 157 of the duct 156. Accordingly, by driving the blower 158, air is blown from the air outlet 162 of the duct 156 toward the recording paper P stored in the paper feed tray 44 in the storage frame 52.

  On the other hand, the duct 152 is substantially L-shaped, and one opening is an air suction port 154 and is attached to the side wall 52C. The other opening 153 is connected to the side of the blower 158 that sucks air. When the blower 158 is driven, negative pressure is generated at the air suction port 154 of the duct 152, and the housing frame 52 extends from the air suction port 154. Inside air is sucked.

  A filter 160 is provided in the vicinity of the duct 152 connected to the blower 158. The filter 160 captures paper dust contained in the air in the housing frame 52 sucked from the air suction port 154. The air from which the paper dust has been removed is sucked into the blower 158 and blown from the blower 158 to the duct 156.

  Next, the operation of the third embodiment of the present invention will be described.

  As shown in FIG. 6, a blower 158 connected to a blowing duct 156 is used as means for generating a negative pressure at the air suction port 154 of the suction duct 152. As a result, negative pressure is generated at the air suction port 154 in order to blow air from the air outlet 162 of the duct 156 into the housing frame 52 and to suck air in the housing frame 52 from the air suction port 154 of the duct 152. Therefore, it is not necessary to arrange a blower and a fan, respectively, which leads to downsizing of the sheet feeding device 150 and saving of power consumption.

  In the present embodiment, the air suction port 154 of the duct 152 that sucks the air in the housing frame 52 is installed on the side wall of the housing frame 52. However, the suction port is a top plate 52B or the bottom surface of the housing frame 52. You may install in 52D. A plurality of suction ports may be provided.

1 is a schematic view of an image forming apparatus equipped with a sheet feeding device according to a first embodiment of the present invention. 1 is a perspective view showing a paper feeding device according to a first embodiment of the present invention. 1 is a side view illustrating a sheet feeding device according to a first embodiment of the present invention. It is a side view which shows the paper feeder which concerns on the 2nd Embodiment of this invention. It is a side view which shows the other form of the paper feeder which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the paper feeder which concerns on the 3rd Embodiment of this invention. It is a side view which shows the paper feeding apparatus which concerns on the 3rd Embodiment of this invention. It is explanatory drawing which shows the conventional paper feeder.

Explanation of symbols

40 Paper feeding device 44 Paper feeding tray 66 Roll unit (paper feeding device)
74 Air spraying device 77 Blower 78 Air inlet (paper dust suction port)
80 fan (paper powder suction means)
82 Filter (Air filter)
84 Paper feeder 86 Air intake (paper dust suction port)
88 Fan (Paper powder suction means)
90 Air intake (paper dust suction port)
92 Fan (Paper powder suction means)
94 Filter (Air filter)
150 Paper Feed Device 154 Air Suction Port (Paper Powder Suction Port)
156 Air spraying device 158 Blower 160 Filter (Air filter)

Claims (6)

In a sheet feeding device comprising: a sheet accommodating portion that accommodates a sheet; a sheet supply member that sends out a sheet accommodated in the sheet accommodating portion; and an air blowing device that blows air on the sheet accommodated in the sheet accommodating portion. ,
A paper feeding device having paper dust suction means for sucking paper dust.   2. The paper feeding device according to claim 1, wherein the paper dust suction port of the paper dust suction means is provided at a position where the uppermost sheet of the sheet is not sucked.   The paper feeder according to claim 1 or 2, wherein the paper dust suction port is provided above the uppermost sheet.   The paper feeding device according to claim 1, wherein the paper dust suction port is provided below the sheet storage portion.   The paper feeder according to any one of claims 1 to 4, wherein an air filter is provided in the paper dust suction port.   6. The paper feeding device according to claim 5, wherein the air blowing device generates a negative pressure at the paper dust suction port of the paper dust suction means.

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