JP2007071998A - Apparatus for removing/collecting toner, image forming apparatus, and method for removing/collecting paper powder and toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly reliable apparatus for removing/collecting toner in which the degradation in image quality due to foreign substances is prevented and the early damage of a cleaning means of an image carrier is averted, an image forming apparatus, and an apparatus for removing/collecting paper powder and the toner. <P>SOLUTION: The apparatus for removing/collecting the toner includes a means for removing at least one of the paper powder or toner existing on the surface of the image carrier and a collecting section for collecting at least either of the paper powder or the toner collected from the removing means; in which the removing means is made to abut on the carrier and to remove at least one of the paper powder or the toner remaining on the carrier surface, a receiving member for receiving at least either of the paper powder or the toner removed from the removing member and a conveying member for conveying the paper powder or the toner removed from the removing member toward the end part direction of the receiving member; and the receiving member has a transmitting member which receives the stress from the conveying member to convey the paper powder or the toner in the following direction of the image carrier. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a device for removing and collecting toner such as paper dust produced by paper and additives used during paper manufacture, an image forming apparatus, and a method for removing and collecting paper powder and toner.

  In recent years, due to resource problems such as reuse of resources and prevention of wasteful use, image forming apparatuses that fix and handle images on paper due to heavy use of recycled paper and additives for ensuring the characteristics of paper have come out of paper. Is affected by paper dust or additives contained.

  The inventors of the present invention have produced an experimental device that holds a polyurethane material with a holding member, abuts against the image carrier, and removes paper dust from the image carrier, and changes paper types to remove and collect paper dust. The experiment was conducted.

  The removal of paper dust from the image carrier has found good conditions with the blade of the removal member made of polyurethane, but when the number of sheets passed reaches several hundred, the tip of the blade and the conveying roller In the meantime, paper dust accumulated, and this paper powder became a lump and slipped through the blade.

  The slipped paper dust moves with the paper as a medium for image formation, and reaches a transfer area where the toner image is transferred to the paper. For example, a regular transfer image cannot be obtained. In addition, paper dust accumulates on the photosensitive member or intermediate transfer member carrying the image to be transferred, and cleaning with a cleaning means provided on the photosensitive member or intermediate transfer member becomes impossible, thereby degrading the image quality. Also become.

  In an attempt to solve the above problems, the blade inclination was changed to make it easier for the scraped foreign material to fall.However, the foreign material mixed with the additive and paper fiber contained in the paper has a high viscosity and is located below the blade. It didn't fall and I didn't get a solution. In particular, when the moisture content of the paper increases due to environmental conditions, the fluidity of the paper powder after scraping from the paper transport means deteriorates, the state of adhering to the blade increases, and the separated foreign matter is collected. Attempts were made to transport with an auger, but it remained attached to the auger and did not move in the transport direction.

  The experimental device was manufactured assuming a waste toner transport system in which the toner remaining on the photoreceptor is scraped with a blade, dropped, and transported by an auger. Thus, the conventional toner transport and recovery system could not be adopted.

Conventionally, in an image forming apparatus and a paper feeding device used therefor, in order to prevent the paper dust from the paper from being deposited on the paper transport roller, a blade or a brush is brought into contact with the paper transport roller, A scraping method has been proposed (see, for example, Patent Documents 1, 2, and 3).
Japanese Patent Laid-Open No. 10-279112 Japanese Patent No. 2761748 Japanese Patent Laid-Open No. 5-127777

  However, as a method for taking out and removing foreign matter from the collecting means, the method described in Patent Document 1 is attached to an adhesive tape and removed by an operator. The method described in Patent Document 2 includes an operator. The method described in Patent Document 3 is a method in which toner and paper dust remaining on the surface of the photoreceptor are scraped off with a blade and conveyed by a feed screw (auger). It is. In these methods, even if the paper dust can be removed from the surface of the paper conveying roller, the subsequent processing and treatment are at most about the method of allowing it to fall naturally to the collecting means prepared below the blade for removal.

  The present invention has been made in consideration of the above-described circumstances, and even if a paper that easily generates a large amount of foreign matter including paper dust or a paper additive is used, the image quality is prevented from being deteriorated by the foreign matter. It is an object of the present invention to propose a highly reliable toner removal / collection apparatus, image forming apparatus, and paper dust / toner removal / collection method in which the carrier and the cleaning means are not damaged or deteriorated at an early stage.

  The present invention also provides a toner removal / collection device, an image forming apparatus, and a paper that can remove paper dust and toner adhering to the intermediate transfer belt and prevent paper conveyance failure and image quality failure due to paper dust and toner. The object is to propose a method for removing and collecting powder and toner.

  Furthermore, the present invention provides a toner removing / collecting device, an image forming apparatus, and a paper dust and toner that can save and save space by transporting and discharging the removed paper dust and toner to a predetermined place (direction). The purpose is to propose a removal and recovery method.

  Further, the present invention improves the assembling and exchanging properties of the receiving member, facilitates toner scattering prevention and discharge processing, and noises during image formation (ON / OFF of driving source, vibration during operation, etc.) And a toner removal / collection device, an image forming device, and a paper dust / toner removal / collection method that can guarantee good image formation.

  The invention according to claim 1 is a collection having means for removing at least one of paper dust or toner present on the surface of the image carrier and a collection unit for collecting at least one of paper dust or toner collected from the removal means. A removing device, wherein the removing means is in contact with the carrier and removes at least one of the paper dust or toner remaining on the surface of the carrier, and the paper removed from the removal member A receiving member that receives at least one of powder and toner, and a conveying unit that conveys the paper powder or toner removed from the removing member toward an end portion of the receiving member, the receiving member including the conveying unit It is characterized by having a transmission means for conveying the paper dust or toner in the subordinate direction of the image carrier in response to the stress from.

  According to a second aspect of the present invention, in the toner removing / collecting apparatus according to the first aspect, the transmission means is a cam follower.

  According to a third aspect of the present invention, in the toner removing / collecting apparatus according to the second aspect, the receiving member is responsive to a repulsive force corresponding to a distance moved by the receiving member due to a stress transmitted through the cam follower. Restoring means for applying a repulsive force to the receiving member so as to restore the receiving member to the original position, and a restraining means for restraining the receiving member to which the repulsive force is applied by the restoring means to return to the original position. It is characterized by having.

  According to a fourth aspect of the present invention, in the toner removing / collecting device according to the second aspect, the receiving member is responsive to a repulsive force corresponding to a distance moved by the receiving member due to a stress transmitted through the cam follower. A restoring means for applying a repulsive force to the receiving member so as to restore the receiving member to its original position, and the receiving member to which the repulsive force is applied by the restoring means is smoothly followed by the guided means and the guide means. And a stopping means for stopping in the original position so as to return in operation.

  According to a fifth aspect of the present invention, in the toner removing / collecting apparatus according to any one of the first to fourth aspects, the image carrier is an intermediate transfer belt.

  According to a sixth aspect of the present invention, in the toner removing / collecting apparatus according to any one of the first to fifth aspects, a storage container for storing the recovered toner is provided at one end of the receiving member.

  According to a seventh aspect of the present invention, there is provided an image forming apparatus comprising the toner removal / collection device according to any one of the first to sixth aspects, wherein the toner removal / collection device is driven to perform non-image formation. It is sometimes operated to convey the toner.

  According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, when the power is turned off or the mode is changed from the energy saving mode to the mode to be used, the toner removing / collecting apparatus together with the pre-drive process before the image forming process Is activated.

  According to a ninth aspect of the present invention, in the image forming apparatus according to the seventh or eighth aspect, the average circularity of the toner used is 0.90 to 0.99.

  A tenth aspect of the present invention is the image forming apparatus according to the seventh or eighth aspect, wherein the toner has a shape factor SF-1 of 120 to 180 and a shape factor SF-2 of 120 to 190. And

  According to an eleventh aspect of the present invention, in the image forming apparatus according to any one of the seventh to tenth aspects, the volume average particle diameter (μm) of the toner used is Dv, and the number average particle diameter (μm) is Dn. Dv / Dn is 1.05-1.30.

  A twelfth aspect of the present invention is the paper dust or toner removal / collection method of the image forming apparatus according to any one of the seventh to eleventh aspects, wherein the drive of the toner removal / collection apparatus is operated when the image is not formed. The toner is transported.

  A thirteenth aspect of the present invention is the paper dust or toner removal / collection method of the image forming apparatus according to the seventh to eleventh aspects, wherein the image forming apparatus is switched from a power-off mode or an energy saving mode to a mode for use. In this case, the toner removing / collecting device is operated together with the pre-driving process before the image forming process.

  The present invention is a method for removing paper dust and toner present on the surface of an image carrier by a removing means and transporting the paper dust to a predetermined recovery unit, at least paper dust and toner removing member that contacts the image carrier, A receiving member that temporarily receives the removed paper dust and toner, a holding unit that holds the receiving member so as to be reciprocally movable in a predetermined direction, and a driving unit that reciprocates the receiving member. The paper dust removal method, which is operated in the drive mode, prevents or stabilizes paper conveyance defects, prevents / stabilizes image formation units due to paper dust and toner, prevents image defects, etc. Stabilize performance.

  Further, the acceleration is changed by the elastic force of the elastic body, the conveyance direction is stabilized in one direction, the conveyance can be ensured, the paper powder and the toner can be easily conveyed / discharged, and the margin is increased.

  Furthermore, paper dust and toner removal and conveyance / discharge can be increased as compared with the separate configuration, and the removal efficiency is increased (inversely, the drive means for reciprocating the paper dust and toner removal is increased by the removal effect ( Time, number of times) can be reduced).

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

  In the image forming apparatus main body 100 shown in FIG. 1, a first image carrier unit 20 having a first image carrier belt 21 that moves endlessly in the direction of the arrow at the upper part of the recording material conveyance path 43A. Further, in the lower part, a second image carrier unit 30 including a second image carrier belt 31 that moves endlessly in the direction of the arrow is disposed. Four first image forming units 80Y, 80C, 80M, and 80K are provided on the upper tension surface of the first image carrier belt 21, and four first image forming units 80Y, 80C, 80M, and 80K are provided on the inclined tension surface of the second image carrier belt 31. Two image forming units 81Y, 81C, 81M, and 81K are provided. Y, C, M, and K along the numbers of the first and second image forming units correspond to the colors of the toner to be handled, Y is yellow, C is cyan, M is magenta, and K is black. is doing. The photosensitive member 1 provided in the first and second image forming units and rotating together with the first image carrying belt 21 and the second image carrying belt 31 also represents Y, M, C, and K in the same meaning. (1Y, ..., 1K, etc.). The photoreceptors 1Y to 1K are arranged at the same interval, and at least at the time of image formation, are in contact with a part of the stretched portion between the image bearing belts 21 and 31, respectively. This contacting surface is called an image receiving surface, and the mutual positional relationship is shown in FIG.

  Although the toner colors to be handled are different, the configurations of the first image forming units 80Y, 80C, 80M, and 80K are the same. Therefore, only the configuration of the first image forming unit 80 will be described with reference to FIG. Therefore, the description is omitted.

  In FIG. 3, during operation of the image forming apparatus 100, an electrostatic photograph is provided around a cylindrical photoreceptor 1 rotatably supported so as to rotate in the direction of the arrow (counterclockwise) by a drive source (not shown). According to the process, a scorotron charger 3, an exposure device 4, a developing device 5, a cleaning device 2, an image forming member such as a light static eliminator Q, a potential sensor S1, and an image sensor S2 are disposed.

  The photoreceptor 1 is formed by forming an organic photo-conducting layer (OPC), which is a photoconductive substance, on a cylindrical surface of aluminum or the like having a diameter of about 30 to 120 mm. A photoconductor on which an amorphous silicon (a-Si) layer is formed can also be used. A belt-like photoreceptor can also be employed. The cleaning device 2 includes a cleaning brush 2a, a cleaning blade 2b, and a recovery member 2c, and removes and recovers toner remaining on the surface of the photoreceptor.

  The exposure device 4 scans the light corresponding to the image data for each color on the surface of each photoreceptor 1 that has been uniformly charged by the charging means, and forms an electrostatic latent image. The exposure apparatus 4 in the illustrated example is an exposure apparatus that includes an LED (light emitting diode) array and an imaging element as light emitting elements, but uses a laser light source, a polygon mirror, etc., and beam light modulated according to image data to be formed. It is also possible to adopt a laser scanning type exposure apparatus. As the charging means, in addition to the charger 3, a type that is brought into contact with the surface of the photoreceptor 1, for example, a charging roller can be adopted.

  The development in this embodiment is a development system that employs a two-component developer composed of toner and carrier. The electrostatic latent image for each color formed on the surface of each photosensitive member 1 by a laser beam with respect to the negatively charged photosensitive member 1 is developed with toner of a predetermined color having the same polarity (negative polarity) as the charged polarity of the photosensitive member. And visualized. So-called reversal development is performed.

  When each color toner of yellow (Y), cyan (C), magenta (M), and black (K) is consumed by a developing device that handles each color, the toner is detected by the magnetically permeable toner detecting means 5e, and the image forming apparatus The toner of each color is supplied to each developing device 5 from a toner cartridge 86 provided in the toner cartridge storage unit 85 inside 100 by a supply unit (not shown).

  As this supply means, a system using a known MONO pump can be adopted. According to this method, since there are few restrictions on the installation location of the toner cartridge, it is advantageous in terms of configuration such as space allocation in the image forming apparatus. Further, since the toner can be replenished in a timely manner, it is not necessary to provide a large toner storage space in the developing device, and the developing device can be downsized.

  The developing device 5 is provided with screws 5c and 5d for stirring and conveying the toner and carrier. When the developing device 5 is mounted on the image forming apparatus 100, one end of the toner replenishing means is connected to a part of the screw 5d. The toner is supplied to the developing roller 5a rotating in the direction of the arrow by the screw 5c, but the thickness of the toner layer on the surface of the developing roller 5a is regulated to a predetermined thickness by the blade 5b. The developing roller 5a is a cylinder made of stainless steel or aluminum, and is supported by the frame of the developing device 5 so as to be rotatable and to be properly secured within a predetermined range from the photosensitive member. A magnet is provided to be constructed. The toner used has an average circularity of 0.90 to 0.99, a shape factor SF-1 of 120 to 180, a shape factor SF-2 of 120 to 190, and Dv / Dn of 1. 05 to 1.30 (Dv is a volume average particle diameter (μm), Dn is a number average particle diameter (μm)). A carrier obtained by a conventionally known method is used. The carrier has a volume average particle size in the range of 25 to 60 μm.

  The second image forming units 81Y to 81K used in the second image carrier unit 30 will also be described as the second image forming unit 81 as a representative with reference to FIG.

  The second image forming unit 81 shown in FIG. 4 has the same constituent members as the first image forming unit 80, but the rotational direction of the photoreceptor 1 is different from that in FIG. However, they are symmetrical to each other with respect to the y-axis passing through the rotation axis 1a of the photosensitive member 1 indicated by an arrow in the drawing. This shape is an important matter although it is related to the arrangement of image forming members provided around the photoreceptor 1. In other words, the first image forming units 80Y to 80K can be combined with a coupling method with the image forming apparatus 100, such as a coupling unit with a driving unit, an electrical connection unit, a toner supply unit, a toner discharge unit, and the like. The second image forming units 81Y to 81K can be compatible with each other. Therefore, it is not necessary to manufacture the developing device, the cleaning device, and the parts individually for the first image forming unit and the second image forming unit, and the efficiency in manufacturing parts and managing parts is high, and the overall cost can be reduced. It is peeled off.

  As a first condition that the first and second image forming units can be used in the first image carrier unit 20 and the second image carrier unit 30 in an axially symmetric shape with respect to the y-axis, a photoconductor 1. A peripheral surface (peripheral end) where no image forming member is provided around 1 is secured, that is, a range in which the image carrying belt can come into contact (contact with or contact with the image carrying belt). Area) is ensured widely, and the second condition is that the arrangement angle between the first image carrying belt 21 and the second image carrying belt 31 is appropriate.

  The first condition and the second condition will be described with reference to FIGS. 3 or 4, the image bearing belts 21 and 31 can be installed between the arrows A1 and A2. That is, the image carrying belt can be installed in the range where the belt does not contact the developing device 5 on the A1 side and the cleaning device 2 on the A2 side. The inclusion of the second image carrier belt 31 in FIG. 3 shows an image carrier belt on which the target image forming unit can be arranged with respect to the y axis including the rotation shaft 1 a of the photoreceptor 1.

  If the image forming unit 80 is turned upside down with respect to an axis orthogonal to the y axis and used as the image forming unit 81, there is an influence of earth gravity, and at least in the developing device 5, the toner is agitated and the developing roller 5a is moved. The toner replenishment conditions are different and must be optimized, and it is impossible to share parts.

  As shown in FIG. 2, the positional relationship between the image receiving surface of the first image carrying belt 21 and the image receiving surface of the second image carrying belt 31 is such that the angle α exceeds 180 ° and reaches 270 °, preferably 210 ° to 255. As the image forming unit, the first image carrying belt shown in FIG. 3 and the second image carrying belt shown in FIG. 4 can be used as the image forming unit. This makes it possible to select an image forming unit that can promote the sharing of components.

  Also, as shown in FIG. 2, since the recording medium conveyance path can be secured almost horizontally and linearly above the second image forming unit 81, the recording medium is excellent in conveyance and reliability, and the image The overall configuration of the forming apparatus is also good.

  In particular, the first image carrier belt is stretched horizontally and flatly, and the second image carrier belt is stretched long and inclined in the vertical direction. The space in the height direction of the image carrier belt can be increased, and paper feeders having a height substantially the same as the height occupied by the second image carrier belt can be installed side by side. As a result, a paper feeding device capable of storing a large amount of paper can be installed, and the paper feeding surface on the upper surface of the paper feeding device and the recording material conveyance path can be made substantially the same height, thereby ensuring the paper feeding / conveying reliability. .

  As described above, in the present invention, the image forming units 80 and 81 have many common points due to the arrangement of the image forming apparatus around the photoreceptor and the arrangement of the image bearing belt, that is, the realization of the second condition. This is also very advantageous in terms of manufacturing.

  The first image carrier belt 21 of the image carrier is supported by a plurality of rollers 23 to 29 and travels in the direction of the arrow (clockwise). The first image carrier belt 21 of the image carrier is a first image forming unit. 80Y to 80K photoconductors 1Y,... The image carrying belt 21 is endless, and is stretched and arranged so that the development process is performed directly in the next image forming unit after the development process of each photoconductor. Further, a primary transfer roller 22 is provided on the inner peripheral portion of the first image carrying belt 21 so as to face the respective photoreceptors 1Y,.

  A removing device 50 </ b> A that removes toner and paper dust is provided at a position facing the roller 23 on the outer peripheral portion of the first image carrying belt 21. The removing device 50A for removing the toner and paper dust wipes off unnecessary toner remaining on the surface of the image bearing belt 21 and foreign matters such as paper dust.

  The members related to the image carrier belt 21 are integrally configured as the first image carrier unit 20 and are detachable from the image forming apparatus 100.

  The second image carrier belt 31 of the image carrier is supported by a plurality of rollers 33 to 38 and travels in the direction of the arrow (counterclockwise), and the second image carrier belt 31 of the image carrier has the second image formation. It is provided in contact with the photoreceptors 1Y,..., 1K of the units 81Y to 81K. The image carrying belt 31 is endless and is stretched and arranged so that a part of each photoconductor after the developing process comes into contact. A primary transfer roller 32 is provided on the inner peripheral portion of the image bearing belt 31 so as to face each of the photoreceptors 1Y,.

  A cleaning device 30 </ b> A is provided on the outer periphery of the second image carrying belt 31 at a position facing the roller 33. The cleaning device 30 </ b> A wipes away unnecessary toner remaining on the surface of the image bearing belt 31 and foreign matters such as paper dust.

  As described above, the members related to the image carrier belt 31 are integrally configured as the second image carrier unit 30 and are detachable from the image forming apparatus 100.

  Next, the configuration and material of the image bearing belt will be described.

  The image carrying belts 21 and 31 are made of, for example, a resin film or rubber having a substrate thickness of 50 to 600 μm as a substrate, and a toner image carried by each photoreceptor 1 is statically applied by a bias applied to the primary transfer rollers 22 and 32. This substrate has a resistance value for enabling transfer onto the belt surface electrically.

For example, carbon is dispersed in polyamide and the volume resistance value is adjusted to about 10 ⁶ to 10 ¹² Ωcm. In order to stabilize the running of the belt, belt detent ribs are provided on one side or both ends of the belt.

In the primary transfer rollers 22 and 32, for example, the surface of a metal roller of a core metal is coated with a conductive rubber material, and a bias is applied to the core metal portion from a power source (not shown). As the conductive rubber material, a material whose resistance is adjusted to about 10 ⁵ Ωcm in which carbon is dispersed in urethane rubber is used.

  The image forming apparatus of the present invention can perform monochrome recording using only black toner. In such a case, there are unused photoconductors (and image forming units, etc.). Therefore, a mechanism for keeping the unused photoreceptors and the image bearing belt 21 or 31 in a non-contact state without operating the unused photoreceptors 1Y, 1C, 1M or the developing device 5 may be provided. In this embodiment, an internal frame (not shown) that supports the roller 26 and the primary transfer roller 22 is provided, is supported so as to be rotatable around a certain point, and is rotated in a direction away from the photosensitive member. Thus, only the photosensitive member 1K comes into contact with the image carrying belt 21 or 31 to execute the image forming process, thereby creating a monochrome image using black toner or the like. Note that the present invention is advantageous not only for black but also for improving the life of the photosensitive member, as long as it is possible to form an image with one type or a reduced number of toners.

Further, a first secondary transfer roller 46 is provided in the vicinity of the support roller 28 on the outer periphery of the first image carrying belt 21. The secondary transfer roller 46 covers the surface of the metal roller of the core metal with a conductive rubber, and a bias is applied to the core metal portion from a power source (not shown). Carbon is dispersed in the rubber, and the volume resistance is adjusted to about 10 ⁷ Ωcm. Toner carried on the first image carrying belt 21 when a bias is applied to the first secondary transfer roller 46 while a recording medium (hereinafter referred to as paper P) is passed between the first image carrying belt 21 and the secondary transfer roller 46. As a result, the image is transferred onto the paper P.

  In the vicinity of the support roller 34 on the outer periphery of the second image carrying belt 31, a transfer charger 47 as a second secondary transfer unit is provided. The transfer charger 47 is a well-known one, and a thin wire of tungsten or gold is used as a discharge electrode, is held by a casing, and a transfer current is applied to the discharge electrode from a power source (not shown). When a transfer current is passed between the image carrying belt 31 and the transfer charger 47 while passing the paper P, an image of toner carried by the second image carrying belt 31 is transferred to the paper P. The polarity of the transfer current flowing through the transfer roller 46 and the transfer charger 47 is a positive polarity opposite to the polarity of the toner.

  On the right side of the image forming apparatus 100, a plurality of sheet feeding apparatuses 40 that store sheets are provided. For example, a paper feed device (tray) 40a that stores a large amount of paper in the upper stage and three paper feed cassettes 40b, 40c, and 40d in the lower stage are arranged so that they can be pulled out to the front side (operation side) at right angles to the paper surface. It is installed. Of the sheets P stored in the sheet feed tray 40a and the sheet cassettes 40b, 40c, and 40d, the uppermost sheet is selectively fed / separated by the sheet feeding / separating means 41A to 41D, A plurality of conveyance roller pairs 42B are fed one by one to the recording medium conveyance paths 43B and 43A.

  A pair of registration rollers 45 are provided in the recording material conveyance path 43A in order to take the feeding timing for feeding the paper P to the secondary transfer position. Further, a jogger 44 for setting the direction perpendicular to the sheet conveyance direction to a normal position is provided in the recording medium conveyance path 43A. The jogger 44 includes guide members that move from both sides toward the edge of the paper in the paper transport direction. The jogger 44 presses the paper for a moment from both sides of the running paper, and the jogger 44 presses the paper into a predetermined position. Align to position.

  The sheet P is conveyed from the registration roller pair 45 in the direction of the transfer area of the first transfer station configured by the first image carrying belt 21 and the secondary transfer roller 46. Thereafter, the sheet P is transported in the direction of the transfer area of the second transfer station constituted by the second image carrier belt 31 and the transfer charger 47.

  In addition, the sheet can be supplied from another sheet feeding device 300 upstream in the conveyance direction of the recording material conveyance path 43C having the conveyance roller pair 42C. The upper paper feed surface of the paper feed tray 40a is arranged so that the paper is fed from the top of the paper feed tray 40a and the paper is conveyed straight and substantially horizontally so as not to bend thereafter. As a result, even paper such as thick and highly rigid paperboard can be reliably fed. The paper feed tray 40a can use paper having various characteristics, and adopts an air paper feed comprising a vacuum (decompression) mechanism so that paper can be reliably fed even when the various papers are stored. be able to. Although not shown, a sensor for detecting a sheet is provided at a key point of the recording material conveyance path, and it can be used as a trigger for various signals based on the presence of the sheet.

  In order to convey the sheet that has passed through the second transfer station to the fixing nip of the fixing device 160 downstream in the conveyance direction of the recording medium in a planar state, a recording medium conveying means 150 is provided on the extension of the recording medium conveyance path 43A. Yes. The recording medium transporting unit 150 includes rollers 152 to 156 that support a conveyor belt 151 that moves endlessly in the direction of an arrow. The cleaning device 150a is opposed to the roller 155 on the outside of the conveyor belt 151, and is opposed to the roller 156. An adsorption charger 57 for adsorbing the recording material P and a static elimination / separation charger 158 opposed to the roller 57 are provided.

  The conveyance belt 151 that moves together with the recording medium P while in contact with the unfixed toner image is negatively charged by the suction charger 157 with the same polarity as the polarity of the toner. As the conveyance belt 151, a metal belt, a polyimide belt (or polyamideimide), a polyamide belt, or the like can be employed. The surface is provided with releasability from the toner and has a chargeable resistance value. The traveling speed of the belt 151 is matched with the traveling speed of the recording medium in the fixing device.

  A fixing device 160 having a heating unit is provided on the downstream side of the recording material transport unit 150 in the paper transport direction. As the fixing device, a type having a fixing roller and a heater inside the roller, a belt fixing device for running a belt to be heated, a fixing device adopting induction heating as a heating method, and the like can be adopted. In the fixing device, the material of the fixing roller and the fixing belt, the hardness, the surface property, and the like are made equal in the upper and lower sides so that the double-sided images of the sheet on which the fixing is performed are the same in hue, glossiness, and the like. In addition, control means (not shown) is used to control fixing conditions based on full-color and monochrome images (including subtracted colors other than full-color), single-sided or double-sided, and optimal fixing conditions according to the type of paper. Control by. A cooling roller pair 170 having a cooling function may be provided in the conveyance path after fixing in order to cool the sheet after fixing and stabilize the unstable toner state at an early stage. In this case, a heat pipe structure roller having a heat radiating portion can be employed. The cooled sheet is discharged and stacked by a discharge roller pair 171 on a discharge stack unit 175 provided on the left side of the image forming apparatus 100. In order to stack a large amount of sheets, this discharge stacking unit can employ a mechanism in which the receiving member moves up and down according to the stack level by an elevator mechanism (not shown). Note that it is also possible to transport the sheet toward another post-processing device through the sheet discharge stack unit 175. As another post-processing apparatus, an apparatus for bookbinding such as punching, cutting, folding, and binding can be exemplified.

  Each color toner cartridge 86Y,..., 86K in which unused toner is stored is detachably stored in the space 85a. A toner conveying means (not shown) supplies toner to each developing device as necessary. In the configuration of this embodiment, the toner cartridge is common to the image forming units 80 and 81 arranged above and below, but can be separated. The toner cartridge 86K for black toner, which is highly consumed, can be set to a particularly large capacity, or a low-consumption toner can be set to a small capacity, or the capacity can be appropriately selected according to the amount used for each toner. Is possible. In the drawing, the storage space 85a is on the rear side when viewed from the operation direction on the upper surface of the image forming apparatus, and a flat portion is secured on the front side of the upper surface of the image forming apparatus, and can be used as a work table, for example.

  An operation provided on the upper surface of the image forming apparatus 100, the display unit 90 is provided with a keyboard and the like, and conditions for image formation can be input, the state of the apparatus and the like are displayed on the display unit, and an image is displayed to the operator. It is user-friendly by disclosing information such as information on the forming apparatus and status.

  In the electrical / control apparatus 195 provided in the image forming apparatus 100, various power supplies, control boards, and the like are protected and housed in a sheet metal frame. By providing the fan F to the high temperature state inside the image forming apparatus due to heat from the fixing device 160 or heat generated from the electrical device, a function deterioration due to heat of members used inside the image forming apparatus is prevented. . The fan F is coupled to the heat radiating portion of the cooling roller pair 170 to improve the cooling effect of the cooling roller pair 170.

  Reference numeral 200 denotes a document reading device, and 300 denotes a paper feeding device that can be additionally installed.

  An example of the operation of these devices will be described below.

  First, the operation of single-sided recording will be described. The operation during single-sided recording for forming a full-color image on one side of the paper P will be described. There are basically two types of single-sided recording methods, which can be selected. The first method is a method in which the image carried on the first image carrier belt 21 is directly transferred to one side of the paper, and the other method is that the image carried on the second image carrier belt 31 is transferred to one side of the paper. This is a direct transfer method.

  In the present embodiment, because of the configuration of the image forming apparatus 100, when an image carried on the first image carrying belt 21 is directly transferred to one side of the paper, the image is placed on the upper surface of the paper and the second image carrying belt. When the image carried on 31 is directly transferred to one side of the paper, the image is formed on the lower surface of the paper.

  In the case where the data to be recorded is a plurality of pages, it is convenient to control the image forming order so that the pages are aligned on the paper discharge stack unit 75. An explanation will be given of a method in which an image is carried on the first image carrying belt 21 and then transferred to a sheet so that the pages are arranged in order from the image data of the last page.

  When the image forming apparatus 100 is operated, the first image bearing belt 21 and the photoreceptors 1Y to 1K in the first image forming units 80Y to 80K rotate. At the same time, the second image carrier belt 31 rotates. However, the photoreceptors 1Y to 1K in the second image forming units 81Y to 81K are separated from the second image carrier belt 31 and are not rotated. First, image formation by the image forming unit 80Y is started. By the operation of the exposure device 4 composed of an LED (light emitting diode) array and an imaging element, light corresponding to image data for yellow emitted from the LED is irradiated onto the surface of the photoreceptor 1Y uniformly charged by the charging device 3. Thus, an electrostatic latent image is formed.

  This electrostatic latent image is developed with yellow toner by the developing roller 5a, becomes a visible image, and is electrostatically applied on the first image carrying belt 21 that moves in synchronization with the photoreceptor 1Y by the transfer action of the primary transfer roller 22. Primary transfer. Such latent image formation, development, and primary transfer operations are sequentially performed in the same manner on the photosensitive members 1C, 1M, and 1K.

  As a result, yellow, cyan, magenta, and black toner images are carried on the first image carrying belt 21 as sequentially overlapping full-color toner images, and are moved in the direction of the arrow together with the first image carrying belt 21. .

  At the same time, the paper P used for recording is fed out from the paper feed tray 40a or the paper feed cassettes 40b to 40d of the paper feed device 40 by one of the paper feed / separation means 41A to 41D for supplying the paper P, and a pair of transport rollers 42B. , 42C to the recording medium conveyance path 43C. Before the leading edge of the sheet is added to the registration roller pair 45, the jogger 44 operates to push both sides of the sheet from both lateral directions with respect to the sheet conveying direction, and the positional alignment in the lateral direction of the sheet starts. It is. The registration roller pair 45 is stationary, and the leading edge of the sheet is stationary while entering the nip of the registration roller pair 45, but the timing is set so that the position with the image on the first image carrier belt 21 is normal. Then, the registration roller pair 45 is rotated to convey the sheet to the transfer area.

  The full-color toner image on the first image carrying belt 21 is transferred to the upper surface of the paper P conveyed in synchronization with the first image carrying belt 21 by receiving a transfer action by the secondary transfer roller 46. The bias applied to the secondary transfer roller 46 has a positive polarity opposite to the charging polarity of the toner.

  Thereafter, the surface of the first image carrying belt 21 is cleaned by the toner and paper dust removing device 50A. The toner remaining on the surfaces of the photoreceptors 1Y to 1K in the first image forming units 80Y to 80K after the primary transfer is removed from the surfaces of the photoreceptors by the cleaning brush 2a and the cleaning blade 2b of the cleaning device 2. Is done. The surface of each photoconductor is subjected to a discharging operation of residual potential by the discharging device Q to prepare for the next image formation / transfer process. The removed foreign matter such as toner is sent to the collecting unit 87 by the collecting unit 2c. Sensors S1 and S2 detect whether the surface potential after exposure on the surface of the photoconductor and the concentration of toner attached to the surface of the photoconductor after the development process are appropriate, and appropriately set image forming conditions. Information is transmitted (transmitted) to control means (not shown) for control.

  The paper P onto which the toner image that has been superposed and carried on the image carrying belt 21 is transferred is transferred toward the fixing device 160 by the carrying belt 151 of the carrying device 150. The surface of the transfer belt 151 is charged in advance by the sheet suction charger 157 so that the sheet P can be reliably transferred together with the transport belt 151. The static elimination / separation charger 158 operates so that the paper P is separated from the transport belt 151 and is reliably sent to the fixing device 160.

  The toner of each color that has been superimposed on the paper P is melted and mixed by being heated by the fixing device 160 to form a complete color image. Since toner is contained only on one side (upper surface) of the paper, less heat energy is required for fixing compared to double-sided recording having toner on both sides. A control means (not shown) optimally controls the power used by the fixing device according to the image. The fixed toner is also rubbed against the guide member or the like in the conveyance path until it is completely fixed on the paper, and as a result, the image is lost or distorted. In order to prevent this problem, the cooling roller pair 170 is operated to cool the toner and the paper. Thereafter, the paper is discharged by the paper discharge roller 171 onto the paper discharge stack unit 175 with the image surface facing upward, for example. In the paper discharge stack unit 175, the recorded material is stacked on top of a young page (a page with a small page number). As described above, in the present invention, since the image forming order is programmed, they are arranged in the page order. Since the paper discharge stack unit 175 descends as the number of discharged paper sheets increases, the paper sheets can be stacked in an orderly and reliable manner, and the page order is not disturbed. Instead of directly stacking the recorded paper on the paper discharge stack unit 175, it is possible to execute a punching process or to transport it to a post-processing device such as a sorter, a collator, a binding device, or a folding device.

  In another method of forming an image on one side of the paper P, image formation is not performed in the first image forming units 80Y to 80K, and image formation is performed in order from image data of young pages for page alignment. Although it differs from the first method in this respect, it is basically the same as the single-sided recording process described above, and therefore details are omitted.

  Next, the operation at the time of duplex recording in which images are formed on both sides of the paper P will be described.

  When a start signal is input to the image forming apparatus, the first image forming units 80Y to 80K described in the single-sided recording operation sequentially form images for each color sequentially on the first image carrying belt 21. In substantially parallel to the step of supporting the first image, the images of the respective colors sequentially formed by the second image forming units 81Y to 81K are sequentially primary-transferred to the second image bearing belt 31 to form the second image. A process of carrying as an image is performed. With the configuration shown in FIG. 1, in order for the first image and the second image to coincide with each other at the leading edge in the sheet transport direction, the second image is formed after the start of the first image formation. Is started. Further, since the sheet is stopped and retransmitted by the registration roller pair 45, the sheet is fed in consideration of the time and aligned by the jogger 44.

  The registration roller pair 45 is transported to a first transfer station constituted by a transfer roller 46 as a first secondary transfer unit and a first image carrying belt 21 at a timing. A transfer current having a positive polarity is applied to the transfer roller 46, and the image is transferred from the first image carrying belt to one side (upper surface in the drawing) of the paper P.

  The sheet P having an image on one side in this way is subsequently fed to the second transfer station having the transfer charger 47 of the second secondary transfer means by the transfer roller 46 being conveyed. Then, by applying a positive polarity transfer current to the charger, the full-color second image previously carried on the second image carrying belt 31 is transferred to the lower surface of the paper P at a time.

  The paper P having the full color toner image transferred on both sides in this way is transferred to the fixing device 160 by the transport belt 151. The surface of the conveyance belt 151 is charged with the same negative polarity as the polarity of the toner by the suction charger. The unfixed toner on the lower surface of the paper is prevented from transferring to the belt. An alternating current is applied to the charge removal / separation charger 158, and the paper is separated from the belt 151 and transferred to the fixing device 160. Then, the toner images on both sides of the paper are melted and mixed by being heated from the fixing device 160. The sheet subsequently passes through the pair of cooling rollers and is discharged onto the discharge stack unit 175 by the discharge roller 171.

  When double-sided recording is performed on a plurality of pages of paper, when the image forming order is controlled so that the image of the young page becomes the bottom surface and is stacked on the discharge stack unit 75, the upper and lower surfaces are removed from the young page. When reversed, the recorded material is the youngest page in order from the top, the second youngest page behind it, the second page is the third youngest page, the back is the fourth youngest page, and so on. Is complete. All the controls including the control of the image forming sequence and the increase of the power input to the fixing device compared with the one-side recording are executed by the control means (not shown).

  The single-sided recording and double-sided recording operations have been described in the case of full-color recording, but the process is the same in the case of forming and fixing a subtractive color image such as monochrome recording with black toner or the like.

  Next, the toner and paper dust removing device according to the present invention will be described.

  As shown in FIG. 1, toner and paper powder removing devices 50A and 50B including blades that contact the outer peripheral surfaces of the intermediate transfer belts 21 and 31 to remove toner and paper powder are provided.

  FIG. 5 is an exploded perspective view showing 50B of the toner removing device and paper dust removing devices 50A and 50B of the present invention shown in FIG. Since 50A has the same configuration, the illustration is omitted.

  FIG. 6 is a plan view in which some constituent members of the paper dust removing device of FIG. 5 are omitted, and FIGS.

  In FIG. 5, a toner / paper dust removing device 50B is in contact with a roller 40b and removes toner and paper dust from the surface of the blade 51, and the toner and paper dust removed below the blade 51. And a receiving member 52 for temporarily receiving. At the end portions 53 and 55 of the receiving member 52, mounting screws (fixing means) 54 and 56 for the leaf springs 63 and 66 are provided, respectively. The holding member 70 fixed to the image forming apparatus main body 100 (FIG. 1) is also provided with fixing means for the leaf springs 63 and 66, for example, mounting screws 71 and 72, respectively, and mounting holes 64 provided in the leaf springs 63 and 66. , 65, 67 and 68 are connected to the receiving member 52, the holding member 70 and the two leaf springs 63 and 66 by screws. As such fixing means, instead of screws, connection by caulking (crimp terminals) or fixing by an adhesive (for example, anaerobic adhesive, two-component adhesive, hot melt, etc.) can be employed.

  A cam follower 58 as an example of a transmission means is rotatably provided on the shaft 57 below the receiving member 52. The image forming apparatus main body is further provided with a stopper 73 as an example of a restraining means in the vicinity of the ends of the driving means 60 and the receiving member 52. The driving means 60 has a configuration in which a cam 62 is fixed to the output shaft of the motor 61. The cam 62 displaces the cam follower 58 by the rotation of the output shaft of the motor, and reciprocates the receiving member 52 supported by the leaf springs 63 and 66 in the arrow x direction (horizontal direction: secondary direction). The arrow y indicates the paper transport direction (main direction).

  The actual operation will be described with reference to FIGS.

  As shown in FIG. 6 a, the end 53 of the receiving member 52 abuts against a stopper 73, and the cam 62 is separated from the cam follower 58. The toner on the receiving member 52, the toner dropped from the blade 51, which is a paper dust removing member, and the paper dust 90 already exist from one end of the receiving member 52 to S1. The collection container 95 indicated by a two-dot chain line has an opening shown in FIG.

  When the motor 61 shown in FIG. 5 operates and the cam 62 rotates in the direction of the arrow shown in FIG. 6, the large diameter portion of the cam 62 contacts the cam follower 58, and at the same time, the leaf springs 63 and 66 are deformed, as shown in FIG. Thus, the receiving member 52 is moved by the distance W. When the cam 62 is further rotated to the state shown in FIG. 6c, the cam follower 58 cannot follow the rotation of the cam 62 because the shape of the cam 62 changes rapidly from the large diameter portion to the small diameter portion, and the leaf springs 63, 66 are restored. The receiving member 52 is rapidly returned by the force, and its end 53 is received by the stopper 73. At this time, the toner and the paper dust 90 cannot be stopped, move to the right in the drawing due to inertia, and are conveyed from one end of the receiving member 52 to the position S2. That is, the toner and the paper dust 90 move by the distance of S1-S2 and approach the collection container 95. The difference in radius between the large diameter portion and the small diameter portion of the cam 62 corresponds to the distance W. While the cam follower 58 contacts the large diameter portion from the small diameter portion of the cam 62, the receiving member gradually moves. However, when the cam follower 58 reaches the small diameter portion, the receiving member 52 is rapidly returned. Thus, acceleration is generated by the change from the large diameter portion to the small diameter portion, and by repeating this movement, the foreign matter on the receiving member 52 is intermittently moved and collected in the collection container 95.

  Next, an example of the movement condition of the receiving member 52 and the movement result of toner and paper dust will be described.

The moving distance w of the receiving member 52 shown in FIG. 6a is an amplitude (unit: mm), and the number of reciprocations N per minute of the receiving member 52 is a vibration frequency (unit: min ⁻¹ ). When the distance TS (unit: mm / sec) was used, the results shown in Table 1 were obtained.

  In addition, although the plate material of the ABS resin was attached to the surface of the receiving member 52 used at this time on which the paper powder was placed and moved, there was not much difference in the transfer effect of the toner and paper powder even with stainless steel and aluminum materials. .

  Further, although the experiment was performed with the receiving member 52 inclined from the horizontal state, the toner and the paper dust were sufficiently conveyed even at an upward inclination of 30 °.

  Next, the collection container 95 will be described.

  When the collection container 95 is filled with toner and paper powder, it is most convenient if the time interval is such that the collection container 95 is taken out. Although it is preferable to discard only the contents accumulated in the collection container 95 and use the container 95 again, the entire container 95 may be discarded. In order to make it easy to take out the container 95, it may be arranged on the operation surface side of the apparatus main body 100, or may be configured as an apparatus main body that can appropriately access the mounting portion of the container. Further, it is possible to provide a detection device for detecting the fullness of the container 95, which can be applied more advantageously in the present invention.

  Next, the drive mode will be described.

  As described above, in order to move the toner and paper dust by reciprocating the receiving member 52 a certain number of times, it is not always necessary to operate the driving means of the receiving member 52. In the present invention, when an apparatus for removing, conveying, and collecting toner and paper dust is employed in an image forming apparatus, the driving means can be operated during a time period when the image forming apparatus is not forming an image. This is advantageous in terms of energy saving, quiet operation noise, and suppression of vibrations that adversely affect image quality. Also, the operation time is set to several seconds or several tens of seconds, and other operations are omitted to be stopped, and the operation is performed every certain time (for example, periodically or linked to the frequency of use of image formation for a predetermined time). it can. In addition, while the image forming apparatus is powered on and warmed up, the drive unit is operated to remove, convey, and transfer toner and paper dust while the cooling fan is operating for a certain period of time after the power is turned off. An apparatus for recovery can be activated. This operation mode is stored in advance in the storage means of the control unit of the image forming apparatus, and the service person can set or change the mode according to the usage state of the user, or input conditions from the operation panel. It can be set or can be set freely by the user.

  7 and 8 are schematic views showing other embodiments.

  In the configuration shown in FIG. 5, the leaf springs 63 and 66, which are examples of the restoring means, are employed. For example, as the restoring means, a coil spring (a tension spring or a compression spring) is acted on the receiving member 52 and a cam is used. It is also possible to employ a mechanism for returning the moved receiving member. Such another embodiment is shown in FIG.

  In FIG. 7, a rotatable roller 74 is supported on shafts 59 provided at two locations of the receiving member 52 to be a guided portion, and the receiving member 52 is moved in the x direction by a guide portion 75 provided on the holding member 70. To make it smooth. The compression spring (or pressing spring) 69 abuts a part of the receiving member and presses the end 53 of the receiving member 52 against the stopper 73. Although the operation is shown in FIGS. 8a to 8c, the description is omitted because it is the same as that described in FIG.

  Further, in the above example, the receiving member 52 is reciprocated, but the blade 51 can be attached to the receiving member 52 and reciprocated together. There is an effect that the toner and paper dust 90 on the boundary between the blade 51 and the roller 40b or on the blade 51 are likely to fall in the direction of the receiving member 52.

  In the present invention, a toner having the following characteristics can be used effectively.

  It is preferable to use a toner characterized in that the average circularity of the toner is in the range of 0.90 to 0.99. It is preferable to use a toner having a shape factor SF-1 in the range of 120 to 180 and a shape factor SF-2 in the range of 120 to 190. A toner having a Dv / Dn in the range of 1.05 to 1.30, where Dv is a volume average particle diameter (μm) of the toner and Dn is a number average particle diameter (μm). It is preferable to use it.

Characteristic 1 (Circularity and circularity distribution)
It is important that the toner that can be used in the present invention has a specific shape and shape distribution, and a toner having an average circularity of less than 0.90 and an irregular shape that is too far from a spherical shape can achieve satisfactory transfer. Therefore, a high-quality image free from dust cannot be obtained. In the shape measurement method, a suspension containing particles is passed through an imaging unit detection zone on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. Toner having an average circularity of 0.90 to 0.99, which is a value obtained by dividing the perimeter of an equivalent circle having the same projected area obtained by this method by the perimeter of the actual particle, has high reproducibility with an appropriate density reproducibility. It is effective to form a clear image. More preferably, the average circularity is 0.93 to 0.97, and the number of particles having a circularity of less than 0.94 is 10% or less. Further, when the average circularity exceeds 0.99, in a system that employs blade cleaning or the like, there is a risk that a defective cleaning on the photosensitive member or the transfer belt may occur, causing stains on the image. For example, when outputting an image with a low image area ratio, there is little transfer residual toner and cleaning defects do not become a problem. However, when outputting an image with a high image area ratio such as a color photographic image, When an untransferred image is left on the photoreceptor due to a defect or the like, a cleaning defect is likely to occur. When the above-described cleaning failure occurs, the possibility of contaminating the charging roller for charging the photoreceptor in contact with the toner increases, and the original charging ability may not be exhibited.

(Measurement method of circularity)
The circularity of the toner particles can be measured as an average circularity by a flow type particle image analyzer FPIA-2100 (manufactured by Toa Medical Electronics Co., Ltd.). Specifically, 0.1 to 0.5 ml of a surfactant, preferably alkyl benzene sulfonate, is added as a dispersant in 100 to 150 ml of water from which impure solids have been removed in advance, and a measurement sample is further added in an amount of 0.1 to 0. Add about 5g. The suspension in which the sample is dispersed is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, the dispersion concentration is set to 3000 to 10,000 / μl, and the shape factor and particle size distribution of the toner are measured with the above apparatus. Obtained by.

Characteristic 2 (shape factors SF-1, SF-2)
SF-1 and SF-2 are parameters representing the shape of the toner, and are familiar parameters in the field of powder engineering. The values of SF-1 and SF-2 described below are set widely.

  As shown in FIG. 9, the shape factor SF-1 is a value indicating the roundness of the shape of the spherical material, and the square of the maximum length MXLNG of the elliptical shape formed by projecting the spherical material on a two-dimensional plane It is expressed by a value obtained by dividing by the area AREA and multiplying by 100π / 4.

That is, the shape factor SF-1 is calculated by the following equation.
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) (Formula 1)

  When the value of SF-1 is 100, the shape of the substance becomes a true sphere, and as the value of SF-1 increases, the shape of the substance becomes indefinite.

  Further, as shown in FIG. 10, the shape factor SF-2 is a numerical value indicating the proportion of the unevenness of the shape of the substance, and the square of the perimeter PERI of the figure formed by projecting the substance on the two-dimensional plane is represented by the figure. It is expressed by a value obtained by dividing by the area AREA and multiplying by 100 / 4π.

That is, the shape factor SF-2 is calculated by the following equation.
SF-2 = {(PERI) ² / AREA} × (100 / 4π) (Expression 2)

  When the value of SF-2 is 100, there is no unevenness on the surface of the substance, and as the value of SF-2 increases, the unevenness on the surface of the substance becomes more prominent. In the embodiment of the present invention, a toner image was randomly sampled 100 times using FE-SEM (S-800) manufactured by Hitachi, Ltd., and the obtained image information (toner image information) is manufactured by Nireco Corporation. This was introduced into the image analysis device (LUSEX 3), analyzed, and calculated using (Equation 1) and (Equation 2).

  It has been clarified by the present inventors that the transfer efficiency increases when the toner shape approaches the spherical shape as much as possible (both SF-1 and SF-2 approach 100). This is because there is only a point contact between the toner particles and the thing (toner particles, image carrier, etc.) in contact with the toner particles due to the shape effect, so that the toner fluidity is increased or the toner is adsorbed on the image carrier, etc. This is thought to be because the force (mirror power) is weakened and is easily affected by the transfer electric field.

  On the other hand, when the shape of the toner approaches a spherical shape, it is disadvantageous for mechanical cleaning (such as blade cleaning). As described above, this increases the toner fluidity, weakens the attracting force (mirroring force) to the image carrier, and the toner easily passes through a slight gap between the cleaning member and the image carrier. it is conceivable that. Therefore, from the viewpoint of cleaning properties, the shape of the toner is somewhat irregular (in a direction in which the value of SF-1 is larger than 100) or uneven (in a direction in which the value of SF-2 is larger than 100). It is preferable to have done.

Characteristic 3 (Dv / Dn: ratio of volume average particle diameter / number average particle diameter)
Dv / Dn is one of the parameters representing the toner particle size distribution. The values of Dv / Dn described below are set widely, and the SR toner of the present invention has a sharp particle size distribution. Such toner has a volume average particle diameter (Dv) of 4 to 8 μm and a ratio (Dv / Dn) to the number average particle diameter (Dn) of 1.05 to 1.30, preferably 1.10 to 1. According to the dry toner of .25, the toner particle size distribution becomes narrow, and the following merits occur.

  Since selective development on the toner particle size surface (toner particles having a (suitable) toner particle size according to the image pattern are selectively developed) is unlikely to occur, a stable image can always be formed. . When a toner recycling system (toner recycling means) is mounted, small-sized toner particles that are difficult to transfer are recycled. However, since the toner particle size distribution is originally narrow, it is difficult to receive the above-described action. Therefore, a stable image can always be formed. In the two-component developer, the toner balance for a long time is performed, the fluctuation of the toner particle diameter in the developer is reduced, and good and stable developability can be obtained even with long-term stirring in the developing device. Even when used as a one-component developer, the balance of the toner is performed, the fluctuation of the toner particle diameter is reduced, the filming of the toner on the developing roller, a blade for thinning the toner, etc. There was no fusion of toner to the member, and good and stable developability and images were obtained even after long-term use (stirring) of the developing device.

  In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. In addition, when the volume average particle size is smaller than the range of the toner used in the present invention, in the two-component developer, the toner is fused to the surface of the carrier by long-term stirring in the developing device, and the charging ability of the carrier is lowered. When used as a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur.

  Further, these phenomena are the same when a toner having a fine powder content wider than the above-described range of the toner used in the present invention is used.

  On the other hand, when the toner particle size is larger than the range of the toner used in the present invention, it becomes difficult to obtain a high-resolution and high-quality image, and the balance of the toner in the developer is reduced. In many cases, the toner particle size fluctuates greatly. It was also clarified that the same applies when the volume average particle diameter / number average particle diameter ratio is greater than 1.30.

  In addition, when the ratio of volume average particle diameter / number average particle diameter is smaller than 1.05, from the viewpoint of stabilizing the behavior of the toner and making the charge amount uniform, generally, the thin line portion is made of small size particles. On the other hand, it is difficult to separate the functions according to the toner particle diameter, such as developing a solid image with a toner having mainly large-size particles.

(Measurement method related to toner particle size)
Examples of the measuring device for the particle size distribution of toner particles by the Coulter counter method include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). The measurement method is described below.

  First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, as the electrolytic solution, for example, approximately 1% NaCl aqueous solution is prepared using primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner can be obtained.

  The channel is 2.00 μm or more to less than 2.52 μm; 2.52 μm or more to less than 3.17 μm; 3.17 μm or more to less than 4.00 μm; 4.00 μm or more to less than 5.04 μm; 5.04 μm or more to less than 6 Less than .35 μm; 6.35 μm to less than 8.00 μm; 8.00 μm to less than 10.08 μm; 10.08 μm to less than 12.70 μm; 12.70 μm to less than 16.00 μm; 16.00 μm to less than 20 Less than 20 μm; 20.20 μm or more to less than 25.40 μm; 25.40 μm or more to less than 32.00 μm; 13 channels of 32.00 μm or more to less than 40.30 μm are used, and the particle size is 2.00 μm or more to 40.30 μm Target less than particles.

  The image forming apparatus of the present invention is provided with at least one of a toner removing device and a paper dust removing device. However, as described above, the toner removing device of the present invention can also have a function of a paper dust removing device. In other words, the paper dust removing device of the present invention has a function of a toner removing device. You can also Therefore, the image forming apparatus of the present invention may be provided with a toner removing device, a paper dust removing device may be provided, or these two may be provided as separate devices. An apparatus having a removal function may be provided in the image forming apparatus of the present invention.

1 is a cross-sectional view illustrating a configuration example of an image forming apparatus of the present invention. It is a schematic sectional drawing which shows the example of arrangement | positioning of an image carrier belt. It is an enlarged view showing an example of a main part for image formation of the present invention. FIG. 6 is an enlarged view showing another main part for image formation of the present invention. It is a disassembled perspective view which shows the example of the paper dust removal apparatus (toner removal apparatus) of this invention. It is a top view for demonstrating the cam operation example of the paper dust (toner) receiving member of the paper dust removal apparatus (toner removal apparatus) of this invention. It is a disassembled perspective view which shows the other example of the paper dust removal apparatus of this invention. It is a top view for demonstrating the cam operation example of the paper dust (toner) receiving member of the other paper dust removal apparatus (toner removal apparatus) of this invention. FIG. 6 is a schematic diagram illustrating toner SF1. FIG. 6 is a schematic diagram illustrating toner SF2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor 1Y, 1C, 1M, 1K Photoconductor 1a Photoconductor rotating shaft 2 Cleaning device 2a Cleaning brush 2b Cleaning blade 2c Collection member 3 Scorotron charger 4 Exposure device 5 Developing device 5a Developing roller 5b Blade 5c, 5d Screw 5e Toner Detection means 20 First image carrier unit 21 First image carrier belt 23, 24, 25, 26 (two), 27, 28, 29 Roller 30 Second image carrier unit 30A Cleaning device 31 Second image carrier belt 34 Support roller 40 Paper feed device 40a Paper feed device (tray)
40b, 40c, 40d Paper feed cassettes 41A to 41D Paper feed / separation means 42B Conveying roller pair 42C Conveying rollers 43A, 43B Recording medium conveying path 43C Anti-recording medium conveying path 44 Jogger 45 Registration roller 46 Transfer roller 47 Transfer charger 50A, 50B Paper dust removing device 51 Blade 52 Receiving member 53, 55 Receiving member end 54, 56 Mounting screw 57 Adsorption charger 57 Roller 63, 66 Leaf spring 64, 65, 67, 68 Mounting hole 70 Holding member 71, 72 Plate spring mounting screw 80Y, 80C, 80M, 80K First image forming unit 81Y, 81C, 81M, 81K Second image forming unit 85 Toner cartridge storage portion 85a Space 86 Toner cartridge 86Y, 86C, 86M, 86K Toner cart 90 Display unit 100 Image forming apparatus main body 150 Recording body transfer means 150a Cleaning device 151 Conveying belt 152, 153, 154, 155, 156 Roller 157 Adsorption charger 158 Static elimination / separation charger 160 Fixing device 170 Cooling roller pair 171 Paper discharge Roller pair 175 discharge stacking unit 200 document reading device,
300 Paper Feeder P Paper Q Photostatic Device S1 Potential Sensor S2 Image Sensor

Claims (13)

A collection / removal device comprising: means for removing at least one of paper dust or toner present on the surface of the image carrier; and a collection unit for collecting at least one of paper dust or toner collected from the removal means,
The removing means includes
A member for removing at least one of the paper dust or toner remaining on the surface of the carrier by contacting the carrier;
A receiving member for receiving at least one of the paper dust or toner removed from the removing member;
Conveying means for conveying the paper dust or toner removed from the removing member in the direction of the end of the receiving member;
The receiving member is
An apparatus for removing and collecting paper dust or toner, comprising: a transmission means for transporting the paper dust or toner in a subordinate direction of the image carrier in response to stress from the transport means.   2. The toner removing / collecting apparatus according to claim 1, wherein the transmission means is a cam follower. The receiving member is
Restoring means for applying a repulsive force to the receiving member so as to restore the receiving member to its original position by a repulsive force according to the distance moved by the receiving member due to the stress transmitted through the cam follower;
The toner removing / collecting device according to claim 2, further comprising: a stopping unit that stops the receiving member to which the repulsive force is applied by the restoring unit so as to return. The receiving member is
Restoring means for applying a repulsive force to the receiving member so as to restore the receiving member to its original position by a repulsive force according to the distance moved by the receiving member due to the stress transmitted through the cam follower;
The receiving member to which a repulsive force is applied by the restoring means has guided means and restraining means for restraining the original position so that the receiving member smoothly moves in the following direction and returns by the guiding means. The toner removing / collecting device according to claim 2.   5. The toner removing / collecting apparatus according to claim 1, wherein the image carrier is an intermediate transfer belt.   6. The toner removing / collecting apparatus according to claim 1, further comprising a storage container for storing the recovered toner at one end of the receiving member. An image forming apparatus comprising the toner removing / collecting device according to claim 1,
An image forming apparatus, wherein the toner is transported by operating the toner removing / collecting device when the image is not formed.   8. The image forming apparatus according to claim 7, wherein when the power is turned off or the mode is changed from the energy saving mode, the toner removing / collecting device operates together with the pre-drive process before the image forming process.   9. The image forming apparatus according to claim 7, wherein the toner used has an average circularity of 0.90 to 0.99.   9. The image forming apparatus according to claim 7, wherein the toner has a shape factor SF-1 of 120 to 180 and a shape factor SF-2 of 120 to 190.   8. The toner according to claim 7, wherein Dv / Dn is 1.05 to 1.30, where Dv is a volume average particle diameter (μm) of the toner used and Dn is a number average particle diameter (μm). The image forming apparatus according to any one of 10. A method for removing and collecting paper dust or toner of an image forming apparatus according to claim 7,
A paper dust or toner removal / collection method, wherein the toner removal / collection device is operated when an image is not formed to convey the toner. A method for removing and collecting paper dust or toner of an image forming apparatus according to claim 7,
The toner removal / collection device operates together with the pre-drive process before the image forming process when the image forming apparatus is switched off or in the energy saving mode. Removal / recovery method.

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