JP2005266551A - Development apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a development apparatus, where operation for starting the use of the new development apparatus is easy by reliably preventing a two-component developer from being spilt, when the development apparatus is carried etc. and where the two-component developer in a developer-housing part will not mix with toner inside a toner-housing part. <P>SOLUTION: The development apparatus is provided with the developer-housing part which is provided adjacently to a developer carrier to house the two-component developer; and the toner housing part to communicate with the developer carrier through the developer-housing part to house the toner so that the toner can be supplied. The two-component developer separated to a developer retreating part flows out to the developer-housing part or a toner supply part. When the development apparatus is new, the two-component developer is housed in the toner-housing part, and a sealing member for isolating the toner-housing part from the developer-housing part is provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, or a multifunction machine having these functions, to which an electrophotographic system is applied, and in particular, a two component having a magnetic carrier and a toner. The present invention relates to an improvement of a developing device that uses a developer and can autonomously control the toner density without using a toner density detecting means.

Japanese Patent Publication No. 5-67233 JP-A-5-119625 Japanese Patent Laid-Open No. 9-22178 JP 2000-352877 A JP-A-9-197833

  Conventionally, as a developing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, or a multifunction machine having these functions to which this kind of electrophotographic method is applied, it is formed on an image carrier such as a photosensitive drum. It is known that the electrostatic latent image formed is visualized with a developer. As a developing method used in such a developing apparatus, a one-component developing method using only toner that is colored particles as a developer, and a two-component method using a mixture of magnetic particles and toner that is colored particles as a developer. Roughly divided into development methods.

  The above two-component developing system has many excellent points such as image quality, cost, and stability. Therefore, there is a wide range of magnetic brush developing systems that develop a toner mixed with a magnetic carrier while conveying the developer by magnetic force. It has been adopted. In this magnetic brush development system, the toner is carried on the surface of the magnetic carrier by the electrostatic force generated by the friction between the toner and the magnetic carrier. When this toner approaches the electrostatic latent image on the image carrier, By flying on the electrostatic latent image by the electric field formed by the electrostatic latent image, the electrostatic latent image is visualized. Further, the developer is repeatedly used while replenishing the toner consumed by the development.

  However, in such a magnetic brush development system, if the toner density (mixing ratio of toner and magnetic carrier) is not controlled to be within a certain range, toner scattering and fogging occur when the toner density increases. On the other hand, when the toner density is lowered, density spots and image omissions occur. Therefore, in order to obtain a stable image, it is necessary to keep the toner density constant.

  Therefore, in the conventional magnetic brush developing system, in order to obtain a stable image, a toner density sensor and a toner replenishing member are mounted on the developing device and control is performed to keep the toner density constant. For example, the toner density is detected by the toner density sensor, and after determining that the toner density has decreased based on the detection information, the toner supply is performed by the toner supply member.

  However, in this type of magnetic brush developing system, a toner density sensor and a toner replenishing member are indispensable, and an increase in the size and cost of the developing device cannot be avoided. Also, there is a problem that the toner density detection system is troublesome, such as creating a density patch to be detected.

  As a prior art for solving such problems, there has already been proposed a developing device that maintains a constant toner concentration without using a toner concentration sensor or a toner replenishing member. The developing device includes a developer accommodating portion that accommodates a two-component developer, and a toner accommodating portion that communicates with the developer accommodating portion and accommodates toner, and the amount of the two-component developer on the developer carrier is set. It is configured to regulate the toner concentration by regulating the toner by autonomously controlling the toner intake of the two-component developer according to the change in the toner concentration of the two-component developer on the developer carrying member. is there.

  This autonomous toner density control method generates a developer moving layer carried and conveyed by a developer carrying member and a developer circulating layer in which the developer circulates in the developer containing portion. The toner is taken in from the communicating toner container. In other words, when the toner is consumed in the developing process, the volume of the developer stored in the developer container is reduced, and the reduced amount of toner is supplied from the toner container to the developer container. In other words, the developer in the developer container holds the toner concentration.

  As an example of the developing device, in the technique disclosed in Japanese Patent Publication No. 5-67233, a magnetic particle layer is formed on a developing sleeve, and toner is supplied so as to come into contact with the magnetic particle layer in a toner supply unit in a container. A developer in which toner and magnetic particles are mixed by the toner supply unit taking in toner from the outer toner layer into the magnetic particle layer by movement of the magnetic particles in the magnetic particle layer accompanying rotation of the developing sleeve By regulating the layer thickness with a regulating member and transporting it to the developing unit, insufficient charging due to excessive supply of toner is prevented.

  In the technique disclosed in Japanese Patent Application Laid-Open No. 5-119625, in a developing sleeve rotating magnetic brush developing device having an internal magnetic pole, an insulating layer is provided on the surface of the developing sleeve and a toner supply roll is disposed near the developing sleeve. And an alternating voltage is applied between the toner supply roll and the developing sleeve to stabilize the toner concentration and toner charging.

  Further, in the technique disclosed in Japanese Patent Application Laid-Open No. 9-22178, magnetic toner is used as the toner constituting the developer, thereby stabilizing toner charging and preventing toner scattering. Further, in the technique disclosed in Japanese Patent Application Laid-Open No. 2000-352877, when the transport speed of the developer carrying member is the fastest, the toner concentration is not more than the limit toner concentration at which the surface of one carrier is completely covered. By configuring the toner concentration so as to achieve this, background contamination and toner scattering are prevented.

  Further, in the technique disclosed in Japanese Patent Application Laid-Open No. Hei 9-197833, the developer carrying member is more developed than the first regulating member that regulates the amount of developer carried and conveyed by the developer carrying member in the developer containing portion. By providing a second restricting member on the upstream side in the agent transport direction, toner concentration adjustment is facilitated.

  However, in each of the above prior arts, the toner concentration is controlled by the change in the developer volume corresponding to the change in the toner concentration and the movement of the developer. The movement needs to be noticeable.

  Under such a demand, it is necessary to increase the developer density in the developer container around the developer carrier with a small amount of developer as compared with the normal two-component development method. The circulation is poor, and there are portions where the developer moves actively and portions where the movement of the developer is not active, so that the toner is not uniformly taken in. In addition, since the amount of developer is small, the absolute amount of toner contained in the developer is small, and because the developer density is high, the volume fluctuation of the developer is gradual even if the toner concentration is reduced, and the toner intake speed is increased. Due to the slowness, the toner is not sufficiently supplied onto the developer carrying member when continuously outputting high-density images with high toner consumption, and a desired density cannot be obtained.

  Furthermore, since the developer amount must be set small in advance, the stress applied to one magnetic carrier is increased and the life of the magnetic carrier is shortened. That is, the running cost increases and the response is slow, which causes a problem that the density of the high-density image cannot be secured.

  Therefore, the present applicant has already proposed a developing device as shown in FIG. 9 in order to solve the above problems (Japanese Patent Application No. 2003-280354).

  As shown in FIG. 9, the developing device 100 according to Japanese Patent Application No. 2003-280354 includes a magnetic field generating means 102 inside, and a developer that carries and carries a two-component developer G containing toner and a magnetic carrier. A developer carrier 101, a developer container 103 for accommodating the two-component developer G adjacent to the developer carrier 101, and a part of the developer container 103 near the developer carrier 101. Adjacent to the developer carrying member 101, the developer agitating member 104 provided, a toner containing unit 105 that is provided in communication with the developer carrying member 101 via the developer containing unit 103, and that accommodates toner so as to be supplied. And a developer retracting portion 106 that is provided downstream of the developer carrying member 101 in the developer conveying direction with respect to the developer containing portion 103 and communicates with the developer containing portion 103, and the developer containing portion. 103 and the developer retracting portion 106 are provided downstream of the developer carrier 101 in the developer conveyance direction, and a part of the two-component developer G carried and conveyed by the developer carrier 101 is used as a surplus developer. The developer accommodating unit 103 or the developer retracting unit 106 is provided with a developer separating unit 107 for separating the excess developer according to the toner density, and is separated into the developer retracting unit 106 as shown in FIG. Further, the two-component developer G is configured to flow out to the developer accommodating portion 103.

  However, the conventional technique has the following problems. That is, in the case of the developing device 100 according to the above Japanese Patent Application No. 2003-280354, as shown in FIG. 9, the developing device 100 is unitized as a CRU together with a photosensitive drum or the like in order to improve maintainability. If it is, it is necessary to prevent the developer from spilling from the developing device due to impact during transportation of the CRU. In the developing device 100, the two-component developer G is accommodated in the developer accommodating portion 103, and the opposing portion between the developer carrying member 101 and the photosensitive drum disposed in the developer accommodating portion 103 is open. Therefore, there is a problem in that the spillage of the two-component developer G from the opening cannot be prevented as it is.

  Further, since the developing device 100 includes the two-component developer G accommodated in the developer accommodating portion 103 and the toner accommodated in the toner accommodating portion 105, due to an impact during transportation of the CRU, etc. The two-component developer G in the developer accommodating portion 103 and the toner in the toner accommodating portion 105 are mixed, and the toner concentration in the developer accommodating portion 103 becomes a predetermined toner concentration when the developing device 100 is used. However, it had the problem of disappearing.

  In order to solve the above problems, it is conceivable to seal the opening of the developing device 100. However, in the CRU in which the developing device 100 is integrated with the photosensitive drum, the opening of the developing device 100 is considered. It is difficult to seal the part. Further, even when the developing device 100 is separate from the photosensitive drum, it is difficult to seal the shaft portions at both ends of the developer carrier 101.

  In order to solve the above problems, it is conceivable that the two-component developer G or the like is not accommodated in the developing device 100 during transportation. In this case, however, the user can store the developer accommodating portion of the developing device 100. In addition to storing the two-component developer G in 103, the toner must be stored in the toner storage unit 105, which is very troublesome.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to reliably prevent spillage of a two-component developer or the like during transportation of the developing device. It is possible to provide a developing device that can be easily operated when starting to use the developing device without the risk of mixing the two-component developer in the developer containing portion with the toner in the toner containing portion. is there.

In order to solve the above-described problems, the invention described in claim 1 includes a developer carrying member that includes a magnetic field generating unit therein and conveys and carries a two-component developer including a toner and a magnetic carrier, A developer accommodating portion for accommodating a two-component developer adjacent to the developer bearing member; a developer agitating member disposed in a portion of the developer accommodating portion adjacent to the developer bearing member; and the developer accommodating portion. A toner container which is provided in communication with the developer carrier through which the toner is accommodated so that toner can be supplied; and adjacent to the developer carrier, the developer carrier is downstream in the developer transport direction with respect to the developer container. A developer retracting portion provided on a side of the developer containing portion and communicating with the developer accommodating portion; and a developer carrying member provided downstream of the developer accommodating portion with respect to the developer accommodating portion and the developer retracting portion. Of the two-component developer carried and conveyed by the body Damming the part as excess developer, and a developer separating means for separating the surplus developer in the developer accommodating portion or the developer saving unit according to the toner density,
In the developing device configured such that the two-component developer separated into the developer retracting portion flows out to the developer accommodating portion or the toner supply portion.
When new, the developing device is characterized in that the two-component developer is accommodated in a toner accommodating portion, and a seal member for separating the toner accommodating portion from the developer accommodating portion is provided.

  According to a second aspect of the present invention, in the developing device according to the first aspect, when the new developing device is used, the developing device is idled after removing the seal member. In the developing device, the two-component developer accommodated in the toner accommodating portion is moved to the developer accommodating portion, and the toner is accommodated in the toner accommodating portion.

  Furthermore, the invention described in claim 3 is the developing device according to claim 2, wherein the toner is accommodated in a toner container that accommodates the toner configured separately from the developing device main body. The developing device is characterized by that.

  According to a fourth aspect of the present invention, in the developing device according to the third aspect, when the new developing device is used, after the idling of the developing device is started, the toner containing container is kept for a predetermined time. The developing device is characterized in that no toner is supplied from the developing device.

  Further, the invention described in claim 5 is the developing device according to claim 3, wherein when the new developing device is used, the toner container is placed in the developing device until the idling of the developing device is completed. A developing device comprising message display means for displaying a message for preventing attachment to the main body.

  According to a sixth aspect of the present invention, in the developing device according to any one of the first to fifth aspects, the new developing device can be mounted on the image forming apparatus main body without removing the seal member. The developing device is configured.

  Further, the invention described in claim 7 is the developing device according to any one of claims 1 to 6, wherein the determination as to whether or not the developing device is new is a memory provided in the developing device. The developing device is performed based on information stored in the means.

  According to an eighth aspect of the present invention, in the developing device according to any one of the first to seventh aspects, the two-component developer accommodated in the developer accommodating portion of a new developing device has a toner concentration. The developing device is set lower than a predetermined value.

Furthermore, the invention described in claim 9 is provided with a developer carrying body having a magnetic field generating means therein and carrying and carrying a two-component developer containing toner and a magnetic carrier, and adjacent to the developer carrying body. A developer accommodating portion for accommodating the two-component developer, a developer agitating member disposed in the developer accommodating portion in the vicinity of the developer bearing member, and the developer bearing via the developer accommodating portion. A toner container that is provided in communication with the body and accommodates toner so as to be able to supply the toner; a developer container that is adjacent to the developer carrier and disposed downstream of the developer carrier in the developer transport direction; and A developer retracting portion communicating with the developer accommodating portion, and provided on the downstream side of the developer carrying member in the developer carrying direction with respect to the developer accommodating portion and the developer retracting portion, and carried and conveyed by the developer carrying member. Use a part of the two-component developer as the excess developer Cough, and a developer separating means for separating the surplus developer in the developer accommodating portion or the developer saving unit according to the toner density,
In the developing device configured such that the two-component developer separated into the developer retracting portion flows out to the developer accommodating portion or the toner supply portion.
When new, the two-component developer is accommodated in a toner accommodating portion, and a seal member is provided for isolating the toner accommodating portion from the developer accommodating portion,
The developing device is characterized in that the developing device is idled for a predetermined time after the developing device is mounted on the main body of the image forming apparatus with the seal member removed.

  According to the present invention, the spillage of the two-component developer or the like can be reliably prevented during transportation of the developing device, and the two-component developer in the developer accommodating portion and the toner in the toner accommodating portion are mixed. Therefore, it is possible to provide a developing device that can be easily operated when starting to use the developing device.

  Embodiments of the present invention will be described below with reference to the drawings.

Embodiment 1
FIG. 2 shows an image forming apparatus to which the developing device according to Embodiment 1 of the present invention is applied.

  In FIG. 2, reference numeral 21 denotes an electrostatic latent image carrier made of an OPC photosensitive member that is rotationally driven along the direction of the arrow. The surface of the electrostatic latent image carrier 21 has a scorotron or a charging surface. It is charged by a charging device 22 such as a roll, and an electrostatic latent image is written by an exposure device 23 having a laser writing device or an LED array. This electrostatic latent image is formed as a potential image based on the contrast with a high potential portion not exposed to light because the surface potential of the electrostatic latent image carrier 21 exposed to light is lowered.

  The developing device 24 accommodates a two-component developer comprising a toner and a carrier is colored particles in the developing housing 31, it is supported with the two-component developer to the developer carrying member 32, the developer carrying member 32 a by applying a developing bias from a bias power source 25, to hold the developer carrying member 32 to an intermediate potential between the high potential portion and a low-potential portion of an electrostatic latent image, it is charged image portions of the electrostatic latent image The toner is developed with toner.

  Further, the transfer device 26 is constituted by, for example, a transfer roll disposed in contact with the electrostatic latent image carrier 21, and a transfer bias in a direction in which the toner image on the electrostatic latent image carrier 21 is attracted by the bias power source 27. Is applied so that the toner image on the electrostatic latent image carrier 21 is transferred to the recording material 28. The toner remaining on the electrostatic latent image carrier 21 is removed by, for example, a doctor blade type cleaning device 29.

  Further, the recording material 28 onto which the toner image is transferred from the electrostatic latent image carrier 21 is conveyed to a fixing device 50, and the toner image is fixed to the recording material 28 by the fixing device 50. The fixing device 50 includes a heat roll method for example, a heating roller 51 and the pressure roll 52, a recording material a toner image by passing the recording material 28 between the heating roll 51 and pressure roll 52 28 is fixed.

  FIG. 1 shows a developing apparatus according to Embodiment 1 of the present invention.

  The developing device includes a developer carrier having a magnetic field generating means therein and carrying and carrying a two-component developer containing toner and a magnetic carrier, and a two-component developer adjacent to the developer carrier. A developer accommodating portion to be accommodated; a developer agitating member disposed in a portion of the developer accommodating portion close to the developer carrying member; and a developer carrying member provided in communication with the developer accommodating portion. A toner storage unit that stores toner in a supplyable manner, and is provided adjacent to the developer carrier and downstream of the developer carrier in the developer transport direction with respect to the developer carrier, and communicates with the developer storage unit. A part of the two-component developer that is provided on the downstream side in the developer transport direction of the developer carrier relative to the developer retracting part and the developer accommodating part and the developer retracting part and is carried and transported by the developer carrier. Dampen as excess developer, toner And a developer separating means for separating the excess developer in the developer accommodating portion or the developer retracting portion according to the degree, and the two-component developer separated into the developer retracting portion is the developer accommodating portion or the toner. It is comprised so that it may flow out to a supply part.

  In this embodiment, the toner is accommodated in a toner container that accommodates toner that is configured separately from the developing device main body.

  That is, as shown in FIG. 1, the developing device 24 includes a developing housing 31 as a developing device body having an opening 311 at a position facing the electrostatic latent image carrier 21. A developer carrying member 32 is disposed facing the opening, and a developer containing portion 33 containing the two-component developer G is disposed in a portion of the developing housing 31 adjacent to the developer carrying member 32. The developer retracting portion 34 provided adjacent to the developer carrying member 32 and on the downstream side of the developer carrying member 32 in the developer conveying direction with respect to the developer containing portion 33, and the developer accommodating portion 33. A toner accommodating portion 35 that communicates with the carrier 32 and accommodates the toner T is formed.

  The two-component developer G is a developer composed of a toner T and a magnetic carrier. As the toner T, for example, a non-magnetic toner is used. If the magnetic property is different from that of the magnetic carrier, a magnetic toner is used. It may be used.

  The developer carrying member 32 includes a rotatable rotating sleeve 321 disposed on the outer periphery and a magnetic pole roll 322 disposed in a fixed state inside the rotating sleeve 321. The rotating sleeve 321 is formed in a thin cylindrical shape from nonmagnetic stainless steel or the like. In addition, the magnetic pole roll 322 has, for example, a conveyance magnetic pole (S2 in this example) aligned with the right side of the horizontal plane passing through the roll body center O, and the conveyance magnetic pole with respect to the rotation direction (counterclockwise) of the rotating sleeve 321. A conveying magnetic pole (N2 in this example) and a developing magnetic pole (S1 in this example) are arranged at an interval of approximately 30 ° from (S2) to the downstream side, while an approximately 30 ° interval from the conveying magnetic pole (S2) to the upstream side. The pickup magnetic pole (N1 in this example), the transport magnetic pole (S3 in this example), and the transport magnetic pole (N3 in this example) are arranged.

  As shown in FIG. 1, the developing magnetic pole (S1) faces the electrostatic latent image carrier 21, and the pickup magnetic pole (N1) captures the two-component developer G in the developer containing portion 33. However, the arrangement and number of the respective magnetic poles may be appropriately selected, while the rotating sleeve 321 rotates counterclockwise and the developing magnetic pole (S1) of the magnetic pole roll 322 is provided. In the developing unit, it faces the electrostatic latent image carrier 21.

  Further, the developer accommodating portion 33 has a space for accommodating the two-component developer G, and a developer agitating member in a portion of the developer accommodating portion 33 that is close to (or in contact with) the developer carrier 32. 36 is rotatably arranged along the clockwise direction. Further, the bottom shape of the developer container 33 has a curved shape along the developer carrier 32 and the developer agitating member 36, and a predetermined interval is provided between the developer carrier 32 and the developer agitating member 36. The developer transport path is secured.

  In this embodiment, as shown in FIG. 1, the two-component developer G is not accommodated in the developer accommodating portion 33 and the two-component developer G is accommodated in the toner accommodating portion 35 when new. Yes.

  Further, as the developer agitating member 36, for example, a member composed of a spiral auger or a member in which a plate-shaped member is fixed in a cross shape on the outer periphery of the rotating shaft is used. The two-component developer G stirred by the developer stirring member 36 is captured in the vicinity of the pickup magnetic pole (N1) of the developer carrier 32 and is carried and conveyed by the rotation of the rotating sleeve 321 of the developer carrier 32. It has become.

  Further, as shown in FIG. 1, the toner storage portion 35 has a toner stirring member 351 for stirring and transporting the stored toner T. The toner stirring member 351 is, for example, attached to the rotating body 352. An elastic film 353 is attached, and the toner T is swept out along the bottom wall surface of the toner storage portion 35. Further, the bottom shape of the toner accommodating portion 35 has a curved shape along the movement rotation locus of the toner agitating member 351, and the connecting portion between the developer accommodating portion 33 and the toner accommodating portion 35 is provided with toner. A supply port 37 is provided, and the lower end edge of the toner supply port 37 is set slightly higher than the center position of the toner stirring member 351. On the other hand, a protrusion 38 is formed at the upper edge of the toner supply port 37 so as to protrude from the upper edge toward the developer stirring member 36. The protrusion 38 extends from the toner container 35. A passage for guiding the toner T to the developer accommodating portion 33 is formed.

  In this embodiment, as shown in FIG. 1, the toner T is accommodated in a toner cartridge 42 as a toner accommodating container that accommodates toner that is configured separately from the developing device main body. . The toner cartridge 42 is mounted on a developing housing 31 as a developing device main body so as to be able to supply toner T on an upper portion of a toner accommodating portion 35 of the developing housing 31. As shown in FIGS. 1 and 3, the toner cartridge 42 is formed in a cylindrical shape, and the toner T is accommodated therein, and the both ends in the longitudinal direction are stirred while the toner T is stirred. A toner conveying member 422 for replenishing toner from a toner replenishing port 421 provided in the section is rotatably disposed. In the toner cartridge 42, as shown in FIGS. 1 and 3, the toner conveying member 422 is rotated at a predetermined timing for a predetermined time, so that the toner in the developing device housing 31 is accommodated through the toner supply port 421. The unit 35 is configured to replenish toner T.

  Further, in the toner cartridge 42, as shown in FIG. 1, when a new developing device 24 is used, the developing device 24 is idled for a predetermined time after starting idling. The toner T is not supplied from the toner cartridge 42 until the two-component developer G is moved to the developer accommodating portion 33.

  In this embodiment, the developer accommodating portion 33 and the developer retracting portion 34 are separated by the developer separating member 39. For example, as shown in FIG. 4, the developer separating member 39 is a plate-like member formed with a width substantially the same as that of the developer carrying member 32. The developer separating member 39 is composed of the developer carrying member. It is inclined and arranged obliquely downward so that the 32 side is the upper side and the opposite side is the lower side. The developer separating member 39 includes an inclined portion 391 disposed in an inclined state, and a lower end portion 392 integrally formed on the lower end portion of the inclined portion 391 downward in the vertical direction. . The upper end 393 of the developer separating member 39 located on the developer carrier 32 side is directly above the transport magnetic pole (N2) in the developer carrier 32 or the transport magnetic pole (N2) as shown in FIG. ) To the upstream side of the developer conveyance direction (clockwise direction side), the surface of the developer carrying member 32 is opposed at a position of several hundred μm to several mm. On the other hand, a lower end 394 opposite to the upper end 393 protrudes downward in the vertical direction in the vicinity of the protrusion 38 described above. Note that the inclination angle of the inclined portion 391 may be arbitrarily set. Further, the end surface of the upper end 393 of the developer separating member 39 is formed to have an end surface along the horizontal direction H0, and the end surface of the lower end 394 is inclined substantially parallel to the left side surface of the protruding portion 38. It is formed to have an end face.

  Further, between the lower end portion 392 and the protruding portion 38 of the developer separating member 39 and between the upper end 393 of the developer separating member 39 and the developer carrier 32, the developer retracting portion 34 and the developer accommodating portion are provided. A circulation path 40 communicating with the portion 33 is formed. In this circulation path 40, for example, the two-component developer G in the developer accommodating portion 33 flows into the developer retracting portion 34 from the inclined portion 391 side, and the inflowed two-component developer G is developed from the lower end portion 392 side. This is a path that flows out to the medicine container 33.

  Further, in this embodiment, the conveyance magnetic pole (N2) and the development magnetic pole (S1) are located at the downstream side (counterclockwise direction side) in the developer conveyance direction from the conveyance magnetic pole (N2) in the developer carrier 32. Between them, a damming portion 41 is disposed so as to face the developer carrier 32. This damming portion 41 has substantially the same width as the developer carrier 32, one end is supported by the development housing 31, and the tip end is connected to the developer carrier 32 with a gap of about several tens to several hundreds of μm. It is close.

  In this embodiment, since a large amount of the two-component developer G is supplied to the damming portion 41, the gap between the upper end portion 39b of the developer separating member 39 and the developer carrier 32 is different from that of the damming portion 41. It is set wider than the gap with the developer carrier 32.

  In this embodiment, the damming portion 41 also functions as a layer thickness regulating function that regulates the layer thickness of the two-component developer G carried and conveyed by the developer carrier 32. What is the layer thickness regulating function? You may make another. In this case, for example, a mode in which the layer thickness regulating member 42 is provided between the damming portion 41 and the developing magnetic pole (Sl) can be mentioned.

  By the way, in this embodiment, when new, the two-component developer is accommodated in the toner accommodating portion, and a seal member for separating the toner accommodating portion from the developer accommodating portion is provided.

  In this embodiment, when the new developing device is used, the two-component developer stored in the toner storage portion is removed by rotating the developing device idly after removing the seal member. The toner is moved to the developer accommodating portion and the toner is accommodated in the toner accommodating portion.

  Further, in this embodiment, when a new developing device is used, the toner is not supplied from the toner container for a predetermined time after the idling of the developing device is started.

  Further, in this embodiment, when a new developing device is used, message display means for displaying a message for preventing the toner container from being attached to the developing device main body until the idling of the developing device is completed is provided. It is configured as follows.

  In this embodiment, the new developing device is configured so that it cannot be attached to the image forming apparatus main body unless the seal member is removed.

  Further, in this embodiment, it is configured to determine whether or not the developing device is new based on information stored in a storage unit provided in the developing device.

  In this embodiment, the two-component developer housed in the developer housing section of a new developing device has a toner concentration set lower than a predetermined value.

  Further, in this embodiment, when new, the two-component developer is accommodated in the toner accommodating portion, and a seal member is provided for separating the toner accommodating portion from the developer accommodating portion, and the seal member is removed. In this state, after the developing device is mounted on the image forming apparatus main body, the developing device is idled for a predetermined time.

  That is, when the developing device 24 is new, that is, when shipped from the factory, the developer accommodating portion 33 and the toner accommodating portion 35 of the developing housing 31 are completely isolated by the sealing member 43 for sealing. In addition, not the toner T but the two-component developer G is accommodated in the toner accommodating portion 35. The seal member 43 is attached to the inside of the developing housing 31 with an adhesive, and can be easily peeled off and removed by opening a lid or the like of the developing housing 31. Further, the seal member 43 must be removed by bringing the end of the seal member 43 out of the developing housing 31 and displaying a message such as a notice for the user on the end of the seal member 43. It is configured so that it cannot be attached to the main body of the image forming apparatus.

  Further, as the two-component developer G accommodated in the toner accommodating portion 35, it is of course possible to accommodate a toner prepared to a predetermined toner concentration of 8 to 10% when the developing device 24 is used. The two-component developer G having a toner concentration lower than a predetermined toner concentration (for example, about 6%) may be initially stored in the developer storage unit 33. In this case, even if the two-component developer G having a low toner concentration is stirred by the developer stirring member 36 and the development process is started immediately, the charging property is excellent by the amount of the low toner concentration, and the toner cloud and density spots are reduced. Etc. can be reliably prevented.

  Even in this case, of course, after the use of the developing device 24 is started, the toner density is gradually adjusted to a predetermined toner density by the automatic density control action.

  Further, as shown in FIG. 1, the developing device 24 is provided with a storage means 45 for discriminating between old and new such as a usage history of the developing device 24 on the back surface of the developing housing 31 and a part of the CRU. When the developing device 24 is mounted on the image forming apparatus main body and used, the developing device 24 reads the information stored in the storage unit 45 via the non-contact communication unit, and the developing device 24 It is configured to determine whether or not the product is new.

  In the image forming apparatus main body, when it is determined that the mounted developing device 24 is new, the developing device 24 is always idled for a predetermined time, as shown in FIGS. In addition, the two-component developer G accommodated in the toner accommodating portion 35 is all moved to the developer accommodating portion 33. The developing device 24 is configured so that the toner T cannot be supplied from the toner cartridge 42 into the toner container 35 unless it is idled for a predetermined time.

  Thereafter, the image forming apparatus main body is configured to rotate the toner cartridge 42 for a predetermined time and supply the toner T from the toner cartridge 42 into the toner accommodating portion 35 of the developing housing 31.

  In the above-described configuration, the developing device according to this embodiment can reliably prevent spillage of the two-component developer or the like during transportation of the developing device and the like in the developer container as follows. There is no possibility that the two-component developer and the toner in the toner container are mixed, and the operation when starting to use the developing device is facilitated.

  That is, in the new developing device 24 according to the above embodiment, as shown in FIG. 1, the developer container 33 and the toner container 35 are separated by the seal member 43, and the toner container A two-component developer G is accommodated in 35. When this new developing device 24 is used, as shown in FIG. 6, after the seal member 43 separating the developer containing portion 33 and the toner containing portion 35 is peeled off, this development is performed. The apparatus 24 or the CRU to which the developing device 24 is mounted is mounted on the image forming apparatus main body, and then the developing device 24 is idled for a predetermined time.

  The image forming apparatus main body reads, for example, information stored in the storage unit 45 provided on the back surface of the developing device 24, and determines whether or not the developing device 24 is new. When the image forming apparatus main body determines that the installed developing device 24 is new, the image forming apparatus main body displays a message to that effect on a display panel (not shown) and informs the user that the idle rotation is performed for a predetermined time. It is like that.

  The developing device 24 rotates idly for a predetermined time, so that the two-component developer G accommodated in the toner accommodating portion 35 is all moved to the developer accommodating portion 33 as shown in FIGS. The Thereafter, the developing device 24 stores a predetermined amount of toner T or all the toner T from the toner cartridge 42 in the toner storage portion 35 of the developing device 24.

  Then, as shown in FIG. 8, the developing device 24 has the two-component developer G accommodated in the developer accommodating portion 33 stirred by the developer agitating member 36, and the pickup magnetic pole in the developer carrier 32. Captured by (Nl). After that, the captured two-component developer G is separated from the developer carrier 32 (rotating sleeve 321) by the magnetic attraction force of the pickup magnetic pole (N1) and the transport magnetic pole (S2) and the frictional force between the surface of the developer carrier 32. ) In the rotation direction. The transported two-component developer G, when it reaches the vicinity of the stop part 41, to form the bristles by the conveying pole (N2). Further, the rising of the two-component developer G is regulated by the damming portion 41, so that the developer layer is formed on the developer carrier 32, and the developer layer is formed on the electrostatic latent image carrier. 21 is conveyed to a developing area facing 21. Further, the developer layer of the two-component developer G transported to the development area forms a magnetic brush by the magnetic attraction force of the developing magnetic pole (S1), and the toner T in the two-component developer G forming this magnetic brush is The electrostatic latent image on the electrostatic latent image carrier 21 is visualized by a developing electric field formed between the electrostatic latent image carrier 21 and the developer carrier 32.

  Next, the behavior of the two-component developer G in the vicinity of the damming portion 41 will be described.

  First, in FIG. 8, it is assumed that the toner density of the two-component developer G carried and conveyed by the developer carrier 32 is low. Since the two-component developer G has a small amount of toner covering the surface of the magnetic carrier, a relatively large surface of the magnetic carrier is exposed.

  That is, since the large magnetic attraction force experienced by the two-component developer G from (N2 in this example) the external magnetic field, the two-component developer G low toner concentration is reliably conveyed to the vicinity of stop part 41. The two-component developer G reliably transported to the damming portion 41 pushes out the staying developer staying in the vicinity of the damming portion 41 by the damming force of the damming portion 41 and the magnetic restraining force of the conveying magnetic pole (N2). As shown in FIG. 8, the pushed-out staying developer becomes a falling developer and falls onto the developer separating member 39, passes through the developer retracting portion 34, and then returns to the developer containing portion 33 again. .

  At this time, when the two-component developer G having a low toner concentration is led to the developer retracting portion 34 as described above, a space is made in the developer accommodating portion 33 accordingly. As a result, the two-component developer G that has been in the toner supply path 43 from the toner supply port 37 to the developer accommodating portion 33 is caused by the conveying force of the developer agitating member 36 and the weight of the two-component developer G. As a result, the toner supply port 37 receives the toner T from the toner storage unit 35, and the toner T is quickly supplied to the developer storage unit 33 through the toner supply path 43.

  On the other hand, assuming that the toner density of the two-component developer G carried and conveyed by the developer carrier 32 is high, the two-component developer G has a large amount of toner covering the surface of the magnetic carrier. There is little surface exposure of the magnetic carrier. That is, since the magnetic attractive force received by the two-component developer G from the external magnetic field (N2 in this example) is small, most of the two-component developer G having a high toner concentration is developed with respect to the rotation direction of the developer carrier 32. It will fall at a position upstream of the tip of the agent separating member 39. As a result, the two-component developer G does not reach the staying developer staying in the vicinity of the damming portion 41 and does not fall on the developer separating member 39.

  Therefore, the two-component developer G does not fall on the developer separation member 39 but falls at a position upstream of the upper end portion 39b of the developer separation member 39 with respect to the rotation direction of the developer carrier 32. Then, the process returns directly to the developer container 33. At this time, unlike the case where the toner concentration is low, the toner supply port 37 is blocked by the two-component developer G without creating a space in the developer accommodating portion 33, so that the toner The toner T is not supplied from the storage unit 35.

  As described above, the toner replenishment mechanism according to the present embodiment uses the change in magnetic attraction force in addition to the change in fluidity and bulk of the two-component developer G according to the toner concentration. The toner is supplied to the low two-component developer G, and the toner is not supplied to the two-component developer G having a high toner concentration. When the toner density is low, the two-component developer G is temporarily guided to the developer retracting portion 34, and the bulk change of the two-component developer G in the developer containing portion 33 is emphasized. Accordingly, the two-component developer G in the developer container 33 can quickly take in the toner T in the toner container 35, and can cope with continuous output of high-density images.

  Thus, in the developing device 24, as shown in FIG. 1, the two-component developer G is accommodated in the developer accommodating portion 33 sealed by the seal member 43 when the developing device 24 is transported. Therefore, it is possible to reliably prevent the two-component developer G from spilling to the outside due to an impact during transportation or the like, and the two-component developer G in the developer container 33 and the toner container 35. There is no possibility of mixing with the toner T.

  In the developing device 24, as shown in FIG. 6, after peeling off the seal member 43, the developing device 24 is idled for a predetermined time, and the two-component developer G is supplied by the toner stirring member 351. Therefore, it is only necessary to move the toner cartridge T to the toner storage portion T from the toner cartridge 42, and the operation when starting to use the developing device 24 is facilitated.

  It should be noted that the developing device 24 may be configured not to be new or old, but to always idle for a predetermined time when mounted on the image forming apparatus main body.

1 is a block diagram showing a developing device according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing an image forming apparatus to which the developing device according to Embodiment 1 of the present invention is applied. FIG. 3 is a sectional view showing the toner cartridge. FIG. 4 is a perspective configuration diagram showing the developer separating member. FIG. 5 is an enlarged configuration diagram showing the vicinity of the developer carrying member and the developer separating member. FIG. 6 is a configuration diagram showing a supply state of the two-component developer. FIG. 7 is a configuration diagram showing a supply state of the two-component developer. FIG. 8 is a configuration diagram showing a usage state of the developing device. FIG. 9 is a block diagram showing a conventional developing device. FIG. 10 is an explanatory diagram showing the flow of the developer in the conventional developing device.

Explanation of symbols

  24: developing device, 32: developer carrier, 33: developer accommodating portion, 34: developer retracting portion, 35: toner accommodating portion, 36: developer stirring member, 39: developer separating member (developer separating portion) Means), 43: seal member, G: two-component developer.

Claims (9)

A developer carrying body having a magnetic field generating means therein and carrying and carrying a two-component developer containing toner and magnetic carrier, and a developer containing a two-component developer adjacent to the developer carrying body A developer agitating member disposed in a portion of the developer accommodating portion adjacent to the developer carrying member, and a developer carrying member provided through the developer containing portion to supply toner. A toner accommodating portion to be accommodated, and a developer retracting portion which is provided on the downstream side in the developer transport direction of the developer bearing member with respect to the developer accommodating portion adjacent to the developer bearing member and communicates with the developer accommodating portion. A part of the two-component developer that is provided downstream of the developer carrying member in the developer carrying direction with respect to the developer containing portion and the developer retracting portion and carried by the developer carrying member is used as an excess developer. Development based on coughing and toner density Accommodating portion or a developer separating means for separating the surplus developer to the developer saving unit,
In the developing device configured such that the two-component developer separated into the developer retracting portion flows out to the developer accommodating portion or the toner supply portion.
In a new product, the two-component developer is accommodated in a toner accommodating portion, and a developing member is provided to seal the toner accommodating portion and the developer accommodating portion. When the new developing device is used, the two-component developer accommodated in the toner accommodating portion is moved to the developer accommodating portion by removing the seal member and idly rotating the developing device. A developing device for storing toner in the toner storage portion. 3. The developing device according to claim 2, wherein the toner is accommodated in a toner container that accommodates the toner configured separately from the developing device main body so as to be able to supply the toner. A developing device characterized in that when a new developing device is used, toner is not supplied from the toner container for a predetermined time after the idling of the developing device is started. And a message display means for displaying a message for preventing the toner container from being attached to the developing device main body until the idling of the developing device is completed when a new developing device is used. Developing device. 6. The developing device according to claim 1, wherein the new developing device is configured so that it cannot be attached to the image forming apparatus main body unless the seal member is removed. 7. The developing device according to claim 1, wherein whether or not the developing device is new is determined based on information stored in a storage unit provided in the developing device. A developing device. 8. The developing device according to claim 1, wherein the two-component developer accommodated in the developer accommodating portion of the new developing device has a toner concentration set lower than a predetermined value. A developing device. A developer carrying body having a magnetic field generating means therein and carrying and carrying a two-component developer containing toner and magnetic carrier, and a developer containing a two-component developer adjacent to the developer carrying body A developer agitating member disposed in a portion of the developer accommodating portion adjacent to the developer carrying member, and a developer carrying member provided through the developer containing portion to supply toner. A toner accommodating portion to be accommodated, and a developer retracting portion which is provided on the downstream side in the developer transport direction of the developer bearing member with respect to the developer accommodating portion adjacent to the developer bearing member and communicates with the developer accommodating portion. A part of the two-component developer that is provided downstream of the developer carrying member in the developer carrying direction with respect to the developer containing portion and the developer retracting portion and carried by the developer carrying member is used as an excess developer. Development based on coughing and toner density Accommodating portion or a developer separating means for separating the surplus developer to the developer saving unit,
In the developing device configured such that the two-component developer separated into the developer retracting portion flows out to the developer accommodating portion or the toner supply portion.
When new, the two-component developer is accommodated in a toner accommodating portion, and a seal member is provided for isolating the toner accommodating portion from the developer accommodating portion,
A developing device, wherein the developing device is idled for a predetermined time after the developing device is mounted on the image forming apparatus main body with the seal member removed.

Images