JP2008156095A - Paper feeder - Google Patents

Abstract

Generation of abnormal noise between a paper powder adsorption roller and a sponge member is prevented.
A powder powder such as crystalline cellulose is interposed between a paper powder adsorption roller 13A and a sponge member 72 to reduce frictional resistance.
[Selection] Figure 8

Description

    The present invention relates to a paper feeding device.

  In an image forming apparatus such as a laser printer, paper (recording medium) is separated and fed one by one while being sandwiched between a paper feed roller and a separation pad. Accordingly, paper dust is likely to be generated on the paper due to rubbing with the separation pad, and if such paper powder is mixed into the toner or adheres to the formed image, the image quality is degraded.

In view of this, there has been known one in which, for example, an electrostatically charged paper dust adsorbing roller is provided at a position facing a conveying roller provided in a paper conveying path. This is a scraping member made of a sponge or the like disposed in contact with the paper dust suction roller while the paper dust suction roller adsorbs the paper dust generated on the paper when the paper dust suction roller rotates. The paper dust adsorbed by the paper dust suction roller is scraped off by (paper dust removing means). The paper dust scraped off by the scraping member is transported by the paper dust transporting means and stored in the paper dust storing means.
JP 2003-81477 A

  However, when the paper dust suction roller is rotated, the paper dust suction roller and the scraping member rub against each other, and noise may be generated. In particular, when an unused printer is driven, the frictional resistance generated between the paper dust suction roller and the scraping member is large, and abnormal noise is likely to occur. As a result, the user may feel uncomfortable.

  In order to achieve the above object, the invention described in claim 1 is directed to a paper powder adsorption roller that adsorbs the paper powder adhering to the recording medium in a conveyance path of the recording medium, and a paper powder adsorption roller. A conveyance roller that conveys the recording medium along the conveyance path, and a paper dust removing unit that contacts the paper dust adsorption roller and removes the paper dust adsorbed by the paper dust adsorption roller from the adsorption roller. In the paper feeding device provided with the above, powder is interposed between the paper dust adsorbing roller and the paper dust removing means.

  The invention according to claim 2 is characterized in that the paper dust removing means is composed of a sponge member, and the sponge member is pressed against the paper dust suction roller by the elasticity of the sponge member itself.

  The invention according to claim 3 is characterized in that the paper dust removing means has a sponge member abutting on the paper dust suction roller, a plate member supporting the sponge member, and the sponge member adsorbing the sponge powder via the plate member. And an elastic member that presses toward the roller.

  The invention described in claim 4 is characterized in that the powder is the same raw material as the recording medium.

  The invention according to claim 5 is characterized in that the surface of the paper powder adsorption roller is a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer.

The invention of claim 6 is characterized in that the sponge member is an ether-based urethane foam resin.

  According to the first aspect of the present invention, by causing the powder to intervene between the paper dust suction roller and the paper dust removing means, it is possible to prevent the generation of abnormal noise that occurs when the paper dust suction roller is rotated. Can do. In particular, when the paper dust suction roller is new, a large frictional resistance is generated between the sponge member and the paper dust suction roller, resulting in abnormal noise. Therefore, it is possible to prevent the generation of abnormal noise during the initial use of the paper dust suction roller by interposing powder between the unused paper dust suction roller and the paper dust removing means and reducing the frictional resistance. Become.

  According to the invention of claim 2, the paper dust removing means is constituted by a sponge member, and is pressed against the paper dust suction roller by the elasticity of the sponge member itself. Thereby, it is not necessary to provide another member for pressing the sponge member. Therefore, the number of parts can be reduced.

  According to the invention of claim 3, the elastic member that presses the sponge member toward the paper powder adsorption roller via the plate member supporting the sponge member is provided. By pressing the sponge member toward the paper powder adsorption roller via the elastic member, the pressure on the paper powder adsorption roller can be applied more uniformly.

  According to the invention of claim 4, by making the powder interposed between the paper dust adsorbing roller and the paper dust removing means the same as the raw material of the recording medium, the powder is electrostatically charged like paper dust. Is attracted to the surface of the suction roller that has generated Therefore, even if the paper dust adheres to the paper dust suction roller and moves with the rotation of the paper dust suction roller, it is collected again by the sponge member. Therefore, it is possible to prevent the powder from being conveyed while being adhered to the paper and affecting the image by adhering to the photoreceptor at the transfer position.

  According to the invention of claim 5, by making the surface of the paper powder adsorption roller a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer, the surface of the paper powder adsorption roller is brought into contact (friction) with the sponge member during rotation. Static electricity is likely to occur in the paper, and paper dust can be reliably adsorbed.

  According to the invention of claim 6, by making the sponge member an ether-based urethane foamed resin, static electricity is easily generated on the surface of the paper powder adsorption roller due to contact (friction) with the paper powder adsorption roller during rotation. Powder can be adsorbed reliably.

<Embodiment 1>
Next, a first embodiment of the present invention will be described with reference to FIGS.

1. Overall Configuration of Laser Printer FIG. 1 is a side sectional view showing a schematic configuration of a laser printer 1 as an image forming apparatus of the present embodiment. FIG. 2 is a side sectional view showing a schematic configuration of the laser printer 1 with the front cover 3 opened. FIG. 3 is a cross-sectional view of the laser printer 1.
FIG. 4 is a diagram showing how the process cartridge 26 and the like are replaced. In the following description, the right side in FIG.

The laser printer 1 is a direct transfer tandem type color laser printer, and includes a substantially box-shaped main body casing 2 as shown in FIG. A front cover 3 that can be opened and closed is provided on the front surface of the main casing 2, and as shown in FIG. 2, the main casing is opened forward with a rotating shaft 3 </ b> A at the lower end of the front cover 3 as the center. 2 (removal) of the process cartridge 26 and the belt unit 15 in the belt 2 and removal of the paper 4 jam occurring inside the main casing 2 can be performed (see FIG. 4). The specific configuration of the front cover 3 will be described in detail later.

  As shown in FIG. 1, a paper discharge tray 5 on which paper 4 after image formation is stacked is formed on the upper surface of the main casing 2.

  A paper feed cassette 7 on which paper 4 for forming an image is loaded is attached to the lower portion of the main casing 2 so as to be drawn forward (inserted / removed).

  The paper feed cassette 7 has a box shape with the top opened, and a paper pressing portion that can tilt to lift the front end side of the paper 4 by the bias of the spring 8 is applied to the paper storage portion 7B in the paper feed cassette 7. A plate 9 is provided. In addition, a pickup roller 10 and a separation pad 11 that presses against the pickup roller 10 by biasing of a spring (not shown) are provided at a position above the front end of the sheet storage portion 7B. Further, a pair of paper feed rollers 12 (12A, 12B) is provided obliquely in front and above the pickup roller 10, and above that, as will be described in detail later, a paper dust adsorption roller for adsorbing paper dust adhering to the paper 4 13A and a transport roller 13B that transports the paper 4 from the paper feed roller 12 are arranged to face each other, and are sandwiched between the paper dust suction roller 13A and the transport roller 13B so that the paper 4 is transported through the transport path. It has become.

  As shown in FIG. 1, the uppermost sheet 4 of the sheet feeding cassette 7 is pressed toward the pickup roller 10 by the sheet pressing plate 9, and the pickup roller 10 is rotated between the pickup roller 10 and the separation pad 11 by the rotation of the pickup roller 10. Each sheet is separated when sandwiched between. Then, the paper 4 sent out between the pickup roller 10 and the separation pad 11 is sent out by the paper feed roller 12 to the paper powder adsorption roller 13A and the conveyance roller 13B side (downstream of the conveyance path).

  Inside the main casing 2, a scanner unit 27, four process cartridges 26, and a belt unit 15 are provided.

  The scanner unit 27 is fixed to the upper part inside the main casing 2 and irradiates the surface of the corresponding photosensitive drum 31 with laser light L for each color based on predetermined image data at high speed.

  The four process cartridges 26 are arranged below the scanner unit 27, and can be attached and detached in the front-rear direction corresponding to the colors magenta, yellow, cyan, and black.

  Each process cartridge 26 includes a photosensitive drum 31, a scorotron charger 32, and a detachable developing cartridge 34.

  The photoconductor drum 31 includes a grounded metal drum body, and the surface layer thereof is covered with a positively chargeable photoconductive layer made of polycarbonate or the like.

  The scorotron charger 32 is disposed opposite to the photosensitive drum 31 at a predetermined interval so as not to come into contact with the photosensitive drum 31 in the diagonally upper rear side of the photosensitive drum 31. The scorotron charger 32 uniformly charges the surface of the photosensitive drum 31 to positive polarity by generating corona discharge from a charging wire such as tungsten.

The developing cartridge 34 has a substantially box shape, and a toner storage chamber 38 is provided in an upper portion thereof, and a supply roller 39, a developing roller 40, and a layer thickness regulating blade 41 are provided below the developing cartridge 34. Each toner storage chamber 38 stores positively chargeable nonmagnetic one-component toner of each color of yellow, magenta, cyan, and black as a developer. Each toner storage chamber 38 is provided with an agitator 42 for stirring the toner.

  The supply roller 39 is configured by coating a metal roller shaft with a conductive foam material, and the developing roller 40 is configured by coating the metal roller shaft with a conductive rubber material. Yes. The toner discharged from the toner storage chamber 38 is supplied to the developing roller 40 by the rotation of the supply roller 39 and is positively frictionally charged between the supply roller 39 and the developing roller 40. Further, the toner supplied onto the developing roller 40 enters between the layer thickness regulating blade 41 and the developing roller 40 with the rotation of the developing roller 40, where it is further sufficiently frictionally charged to have a constant thickness. It is carried on the developing roller 40 as a thin layer.

  The surface of the photosensitive drum 31 is first uniformly charged positively by the scorotron charger 32 when rotating. Thereafter, exposure is performed by high-speed scanning of laser light from the scanner unit 27, and an electrostatic latent image corresponding to an image to be formed on the paper 4 is formed.

  Next, when the developing roller 40 rotates and the positively charged toner carried on the developing roller 40 comes into contact with and faces the photosensitive drum 31, a static image formed on the surface of the photosensitive drum 31 is formed. The electric latent image is supplied. As a result, the electrostatic latent image on the photosensitive drum 31 is visualized, and a toner image by reversal development is carried on the surface of the photosensitive drum 31.

  Thereafter, the toner image carried on the surface of each photosensitive drum 31 is transferred while the paper 4 conveyed by the conveying belt 18 passes through each transfer position between the photosensitive drum 31 and the transfer roller 19. The images are sequentially transferred onto the paper 4 by a negative transfer bias applied to the roller 19. The sheet 4 having the toner image transferred thereon is then conveyed to the fixing device 43.

  The fixing device 43 is disposed behind the conveyance belt 18 in the main body casing 2. The fixing device 43 includes a heating roller 44 that is rotationally driven with a heat source such as a halogen lamp, and a pressure roller 45 that is disposed below the heating roller 44 so as to face the heating roller 44 and is driven to rotate. It has. The fixing device 43 fixes the toner image on the paper 4 by heating the paper 4 carrying the four color toner images while being nipped and conveyed by the heating roller 44 and the pressure roller 45. The heat-fixed paper 4 is transported to a paper discharge roller 47 provided on the upper portion of the main body casing 2 by a transport roller 46 disposed obliquely above and rearward of the fixing device 43, and the paper discharge roller 47 performs the above-described operation. The paper is discharged onto the paper discharge tray 5.

  The belt unit 15 is provided below the process cartridge 26, and includes a pair of support rollers 16 and 17 that are spaced apart from each other in the front-rear direction, and a conveyor belt 18 that is horizontally installed between the support rollers 16 and 17. And is detachable from the main casing 2.

The rear support roller 17 of the pair of support rollers 16 and 17 is a drive roller that is rotationally driven by the power of a motor (not shown), and the front support roller 16 applies tension to the conveyor belt 18 as will be described later. This is a tension roller. The conveying belt 18 is an endless belt made of a resin material such as polycarbonate, and the paper is placed on the upper surface thereof by circulating and moving counterclockwise in FIG. 1 when the supporting roller 17 as a driving roller is driven to rotate. 4 is conveyed backward. Inside the conveying belt 18, four transfer rollers 19 arranged to face each photosensitive drum 31 included in the process cartridge 26 described later are arranged in a front-rear direction at regular intervals, and correspond to each photosensitive drum 31. The conveyance belt 18 is sandwiched between the transfer roller 19 and the transfer roller 19. At the time of transfer, a transfer bias is applied between the transfer roller 19 and the photosensitive drum 31. The support roller 17 is connected to a gear mechanism (not shown) provided in the main casing 2 when the belt unit 15 is attached to the main casing 2, and is also a motor provided in the main casing 2. It is driven by the power of (not shown).

  A cleaning roller 21 is provided below the belt unit 15 to remove toner, paper dust, and the like attached to the conveyance belt 18. The cleaning roller 21 has a structure in which a foam material made of silicon is provided around a metal shaft member, and is opposed to the metal backup roller 22 provided in the belt unit 15 with the conveyance belt 18 interposed therebetween. Yes. A predetermined bias is applied between the cleaning roller 21 and the backup roller 22, whereby the toner and the like on the conveyor belt 18 are electrically attracted to the cleaning roller 21 side. Further, the cleaning roller 21 is in contact with a metal recovery roller 23 that removes toner or the like adhering to the surface, and the recovery roller 23 is a blade for scraping off the toner or the like adhering to the surface. 24 abuts.

2. Configuration of Front Cover FIG. 5 is a perspective view of the sheet feeding unit 97 provided on the front cover 3 as viewed obliquely from above. 6 is a perspective view seen from the opposite side of FIG. FIG. 7 is a perspective view of a state in which the configuration including the gear connected to the paper feed unit 97 is removed. FIG. 8 is an enlarged side sectional view of a part of the laser printer. FIG. 9 is an enlarged view of the vicinity of the sheet feeding unit in the side cross section taken along the line AA of FIG. FIG. 10 is a side sectional view when the front cover 3 of FIG. 9 is in the open position. FIG. 11 is a perspective view showing a configuration for transmitting a rotational force to the conveying roller 13B and the paper dust suction roller 13A. FIG. 12 is a side sectional view showing a state in which the constant velocity swing joint 60 is connected between the connecting shaft portion 65 and the conveying roller 13B. FIG. 13 is a perspective view showing a state where the constant velocity swing joint 60 is removed. FIG. 14 is a diagram conceptually illustrating a configuration in which the transport roller 13B can be swung.

  As shown in FIG. 1, the front cover 3 has a cover main body 95 that closes the opening 2A of the main body casing 2, and a cover connecting portion 96 that connects the lower end of the cover main body 95 and the rotary shaft 3A on the main body casing 2 side. (See FIG. 2).

  A paper feed unit 97 that conveys the paper 4 to the belt unit 15 side is provided on the cover connecting portion 96 side of the cover main body 95 (in the lower part of the cover main body 95 in FIG. 1).

  As shown in FIG. 1, the sheet feeding unit 97 is arranged and conveyed at a position opposite to the conveying roller 13B for guiding the sheet 4 to the conveying path on the belt unit 15 side and the conveying roller 13B (between the conveying roller 13B). A paper dust adsorption roller 13A (pinch roller) that adsorbs the paper dust adhering to the paper 4 and a paper dust removing unit 70 that removes the paper dust adsorbed by the paper dust adsorption roller 13A ("paper" of the present invention And an auger member 80 that conveys the paper dust removed by the paper dust removal unit 70 to the paper dust storage chamber 90.

  Here, in the present embodiment, the paper dust suction roller 13A is pivotally supported at a fixed position, while the transport roller 13B is pivotally supported with respect to the paper dust suction roller 13A.

<Configuration for swinging the transport roller>
The paper dust suction roller 13A has a metal roller shaft 14A, and the roller shaft 14A of the paper dust suction roller 13A is pivotally supported in a state where the shaft position is fixed by the bearing portion of the side wall 97A of the paper feed unit 97 (main body). As shown in FIG. 5, a driven gear portion 71 is connected to the roller shaft 14A. Then, the driven gear portion 71 is meshed with a main driving gear portion 61 of a constant velocity swing joint 60 which will be described later, so that the paper powder adsorption roller 13A rotates.

  The conveyance roller 13B is configured such that the circumference of the metal roller shaft 14B is covered with an elastic body such as rubber, and the roller shaft 14B of the conveyance roller 13B is, as shown in FIG. The roller shaft 14B) is supported by a swinging bearing portion 50 that can swing the roller shaft 14B (supported so as to be swingable with respect to the paper dust suction roller 13A).

  As shown in FIG. 14, the oscillating bearing portion 50 is formed in a thin plate shape that is a dogleg shape (a shape in which both end portions are bent slightly toward the same direction at the center in the longitudinal direction), A roller shaft 14B of the transport roller 13B is pivotally supported in a circular hole in the substantially central portion, and an engagement protrusion that protrudes in a circular shape from the side wall 97A of the paper feed unit 97 is supported at the end on the downstream side in the transport direction. An escape hole 51 for accommodating the portion 98 is provided. Further, a pressing spring 55 is connected to an end on the upstream side in the conveying direction, and the conveying roller 13B is urged toward the paper powder adsorption roller 13A by the pressing spring 55.

  The escape hole 51 is an elliptical hole that is long in the front-rear direction (conveying direction). When the circular engagement convex part 98 is accommodated in the escape hole 51, the engagement convex part 98 and the relief hole 51 are provided. A gap (escape) is generated between the inner periphery of the inner wall and the inner periphery.

  Further, a guide hole 52 is provided in the side wall 97A of the paper feed unit 97, and this guide hole 52 is in the vertical direction (the direction connecting the axis center of the transport roller 13B and the axis center of the paper dust suction roller 13A). It is a long oval hole, and the guide roller 52 accommodates (bears) the circular roller shaft 14B of the transport roller 13B so that it can move (swing) along the longitudinal direction of the guide hole 52. .

  The roller shaft 14B of the transport roller 13B is supported by the guide hole 52 in the side wall 97A of the paper feed unit 97, so that the transport roller 13B can swing in the vertical direction. The relief hole 51 is provided if the escape roller 51 is not provided and the swing bearing portion 50 is simply rotated around the engagement convex portion 98. This is because (moving) cannot be performed (an attempt is made to move in an arc shape around the engaging convex portion 98).

  Further, as shown in FIG. 11, the roller shaft 14B of the transport roller 13B has a constant velocity swing joint 60 that transmits a rotational driving force from a connecting shaft portion 65 that rotates by receiving a rotational driving force from a motor (not shown). Are connected.

  The constant velocity swing joint 60 is made of a strong resin, and can transmit a rotational driving force to the transport roller 13B even if the transport roller 13B swings in the transport direction. Further, in the constant velocity swing joint 60, a main driving gear portion 61 is provided on the outer periphery of the connecting portion side with the connecting shaft portion 65, and the main driving gear portion 61 is a driven gear portion of the paper dust suction roller 13A. The paper dust suction roller 13 </ b> A can be rotated by being engaged with 71.

  Note that both ends of the constant velocity swing joint 60 are configured as so-called universal joints, and as shown in FIG. 13, fitting recesses 62 formed with notches 62B are provided at both ends of a circular recess 62A. 12 (see FIG. 12), a fitting convex portion 63 that fits the fitting concave portion with almost no gap is provided at the end of the connecting shaft portion 65 and the roller shaft 14B of the conveying roller 13B on the constant velocity swing joint 60 side. The fitting concave portion 62 and the fitting convex portion 63 are concavo-convexly fitted to each other, so that the rotation direction is achieved at the coupling portion between the constant velocity swing joint 60 and the connecting shaft portion 65 (and the roller shaft 14B) during rotation. No slipping occurs.

<Configuration for removing paper dust adhering to paper>
As shown in FIG. 8, the surface or all of the paper dust suction roller 13A is formed of a fluororesin that is easily charged, and the paper dust suction roller 13A is contacted (friction) with the sponge member 72 when the paper dust suction roller 13A rotates. Static electricity is generated on the surface of the powder adsorbing roller 13A. In particular, when a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) is used as the fluororesin, the chargeability is good. And the paper dust adhering to the paper 4 conveyed by this static electricity is drawn near.

  The paper dust removing unit 70 includes a sponge member 72 that scrapes the paper dust on the surface of the paper dust suction roller 13A, and a paper dust receiving unit 73 that receives the paper dust scraped by the sponge member 72. Yes.

  The sponge member 72 has a rectangular parallelepiped shape, and is made of, for example, an ether-based urethane foam resin. The sponge member 72 is fixed (adhered) to a metal thin plate 75 (corresponding to the “plate member” of the present invention) supported in a swingable manner on the wall portion inside the cover main body 96, and the sponge member 72 is a metal thin plate 75. The elastic member 69 (corresponding to the elastic member of the present invention) composed of a compression coil spring is pressed to contact the surface of the paper dust suction roller 13A.

  As a result, when the paper dust suction roller 13A rotates clockwise, the paper dust on the surface of the paper dust suction roller 13A is scraped off from the surface of the paper dust suction roller 13A by the sponge member 72 and becomes a lump. It falls to the receiving part 73.

  The powder 120 is interposed between the sponge member 72 and the paper powder adsorption roller 13A. When the paper dust suction roller 13A is new, a large frictional resistance is generated between the sponge member 72 and the paper dust suction roller 13A. By interposing the powder 120 between the sponge member 72 and the paper powder adsorption roller 13A, it is possible to reduce the frictional resistance and prevent the generation of abnormal noise.

  The powder 120 is, for example, cellulose which is the same raw material as the main component of the paper 4. In particular, crystalline cellulose, which is a crystalline powder of cellulose, is the most effective. As the crystalline cellulose, for example, Avicel (registered trademark) manufactured by Asahi Kasei Corporation is preferably used. Since crystalline cellulose is the same raw material as the paper 4, it is attracted to the surface of the suction roller 13A that has generated static electricity like paper dust. Therefore, even if the crystalline cellulose interposed between the sponge member 72 and the paper powder adsorption roller adheres to, for example, the paper powder adsorption roller 13A and moves with the rotation of the paper powder adsorption roller 13A, It is recovered by the sponge member 72 again. By collecting the paper powder 120, it is possible to prevent the powder 120 from adhering to the paper 4 and being conveyed and adhering to the photoconductor 31 at the transfer position, thereby affecting the image.

Similar effects can be obtained if cellobiose, β-D-glucose, etc. have the same molecular structure as cellulose. The powder 120 may have a structure similar to cellulose, such as amylose, amylopectin, or α-D-glucose. Powder 120
The same effect can be obtained even if the molecular structure is not the same as or similar to that of cellulose. For example, Kyner (registered trademark), which is a crystalline polymer of vinylidene fluoride manufactured by Arkema, can be used as a sponge member 72. And the paper powder adsorption roller 13A can be reduced in frictional resistance, and noise can be prevented from being generated.

  The paper dust receiving portion 73 is recessed in an arc shape over the entire width of the transport path of the paper 4, and the lump of paper dust scraped off by the sponge member 72 is dropped on the paper powder receiving portion 73. It is like that.

  As shown in FIG. 3, the auger member 80 is disposed along the paper powder receiving unit 73, and the paper powder on the paper powder receiving unit 73 is disposed inside the main body casing 2 where the paper powder storage port 90 </ b> A is disposed. It is transported to both end portions.

  The auger member 80 is integrally provided with a shaft member 82 and a spiral portion 83 formed in a spiral shape around the shaft member 82. One end of the shaft member 82 is provided with an auger drive gear (not shown) to which power is input from a motor (not shown).

  The spiral portion 83 has a different rotational direction at the substantially central portion of the shaft member 82, and the paper powder conveyance direction is different at the substantially central portion. That is, the paper powder is conveyed toward the side wall 97A on the near side by the rotation of the auger member 80 in a predetermined direction.

  Further, in the front cover 3, an end portion 73 </ b> A of the paper dust receiving portion 73 located at the end of the conveyance path by the auger member 80 is provided with a paper dust passage hole portion 81 through which the conveyed paper dust passes (drops). It has been.

  The paper dust passage hole portion 81 is provided in a tubular shape having a thickness that penetrates in the vertical direction and allows paper dust to pass therethrough, and is provided continuously with the paper dust receiving portion 73. The paper powder passage hole 81 communicates with a paper powder storage chamber 90 (paper powder storage port 90A) described later.

  The paper feed unit 97 is provided with a paper dust storage chamber 90 in which the paper dust that has passed (dropped) through the paper dust passage hole 81 is stored.

  As shown in FIG. 3, the paper dust storage chamber 90 is for storing paper dust inside, and is provided over the entire width of the transport path of the paper 4. It communicates with the passage hole 81.

  Further, as shown in FIG. 9, the paper dust storage chamber 90 includes a primary storage unit 91 in which paper powder conveyed by the auger member 80 is stored, and a secondary storage unit configured to communicate with the primary storage unit 91. 92.

  The primary storage part 91 is a rear end part in the paper feed unit 97 and below the paper powder passage hole 81 in the closed state of the front cover 3 (below the terminal part of the paper powder conveyed by the auger member 80). Is provided.

  The secondary storage part 92 is provided in a substantially latter half part of the lower end part in the paper feed unit 97. Specifically, it is provided from the first portion where the paper dust is accumulated in the primary storage unit 91 (the portion where the paper dust is accumulated in FIG. 9) to the front side to the substantially central portion in the paper feed unit 97. ing.

  In this way, as shown in FIG. 10, the front cover 3 is moved to the open position (a position where the front cover 3 is opened at an angle of approximately 90 degrees or slightly less than the vertically standing closed state). When opened (the open state is maintained), the secondary reservoir 92 is positioned below the left end (the lower end in FIG. 9) of the primary reservoir 91 in FIG. As a result, the paper dust accumulated in the primary storage unit 91 moves (drops), and the paper dust is accumulated at the lower end of the secondary storage unit 92 in FIG.

  The front cover 3 is provided with a manual paper feed port (not shown), from which manual paper feed of a plurality of sizes is possible. More specifically, as shown in FIG. 8, a multi-purpose transport roller 85, a multi-purpose paper feed roller 86, and a multi-purpose separation pad 87 facing the multi-purpose paper feed roller 86 are provided. The paper fed from the manual paper feed port is guided to the multi-purpose paper feed roller 86 by the multi-purpose feed roller 85, and the multi-purpose paper feed roller 86 and the multi-purpose separation pad are rotated by the rotation of the multi-purpose paper feed roller 86. After being sandwiched between the two, the sheets are separated and fed one by one by their cooperation. The fed paper is sent to the paper dust suction roller 13A and the transport roller 13B.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  The sponge member 72 of the present invention is fixed (adhered) to a metal thin plate 75 that is swingably supported by a wall portion inside the cover main body 96, and the sponge member 72 is an elastic material comprising a compression coil spring via the metal thin plate 75. While being pressed by the elastic force of the body 69, it comes into contact with the surface of the paper dust adsorbing roller 13A. For example, as shown in FIG. 15, the sponge member 172 is provided on the main body frame 175, The elastic force of the member 172 itself may come into contact with the surface of the paper powder adsorption roller 13A.

1 is a side sectional view showing a schematic configuration of a laser printer according to Embodiment 1 of the present invention. 1 is a side sectional view showing a state in which the front cover of the laser printer of FIG. 1 is opened. Cross section of laser printer Diagram showing how process cartridges are replaced Perspective view of the paper feed unit as seen from diagonally above The perspective view seen from the opposite side of FIG. The perspective view from which the structure containing the gear connected with the paper feed unit was removed An enlarged side cross-sectional view of a part of a laser printer The figure which expanded the paper feed unit vicinity among the side cross sections in AA of FIG. The figure when the front cover of FIG. 9 is in the open position The perspective view which shows the structure which transmits rotational force to a conveyance roller and a paper dust adsorption | suction roller. Side sectional view showing a state in which a constant velocity swing joint is connected between the connecting shaft portion and the conveying roller. The perspective view which shows the state from which the constant velocity rocking joint was removed The figure which shows notionally the structure which enables a conveyance roller to rock | fluctuate The sponge member is pressed against the paper powder adsorption roller by the elasticity of the sponge member itself

Explanation of symbols

1. Laser printer (image forming device)
2 ... Main body casing 3 ... Front cover (cover)
3A: Rotating shaft of front cover 4 ... Paper (recording medium)
13A ... Paper dust adsorbing roller 13B ... Conveying roller 50 ... Oscillating bearing part 51 ... Escape hole 52 ... Guide hole 55 ... Pressing spring (biasing means)
60 ... Constant velocity swing joint (joint part)
70: Paper dust removing unit (paper dust removing means)
72 ... Sponge member 73 ... Paper powder receiving part 80 ... Auger member (paper powder conveying means)
81 ... Paper dust passage hole 90 ... Paper dust reservoir (paper dust reservoir)
91 ... Primary storage part 92 ... Secondary storage part 120 ... Powder

Claims (6)

A paper dust adsorbing roller that adsorbs the paper dust adhering to the recording medium in the transport path of the recording medium;
A transport roller that is disposed at a position facing the paper dust suction roller and transports the recording medium along the transport path;
In a paper feeding device provided with a paper dust removing means that contacts the paper dust suction roller and removes the paper dust adsorbed by the paper dust suction roller from the suction roller.
A paper feeding device characterized in that powder is interposed between the paper dust adsorbing roller and the paper dust removing means. The paper dust removing means is composed of a sponge member,
The paper feeding device according to claim 1, wherein the sponge member is pressed against the paper dust suction roller by elasticity of the sponge member itself. The paper dust removing means includes a sponge member that contacts the paper dust suction roller,
A plate member supporting the sponge member;
The paper feeding device according to claim 1, further comprising: an elastic member that presses the sponge member toward the paper dust suction roller via the plate member. The paper feeding apparatus according to claim 1, wherein the powder is the same raw material as the recording medium. The paper feeding device according to any one of claims 1 to 4, wherein a surface of the paper powder adsorption roller is a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer. The paper feeding device according to claim 1, wherein the sponge member is an ether-based urethane foam resin.