JP3776702B2 - Development device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a developing device. so In particular, the present invention relates to a developing device that develops an electrostatic latent image formed on a latent image carrier (image carrier) using a developer and the like, and particularly to a developer using a traveling wave electric field. Developing device using a transport mechanism (electric field curtain) In It is related.
[0002]
[Prior art]
Image forming apparatuses using electrophotographic processes such as copying machines, printers, facsimiles, and the like are known, and as a developing device applied to these image forming apparatuses, a two-component developing device using a magnet brush, A method is known in which a single-layer developer is pressed against a developer carrier such as a developing roller with a blade to form a thin layer and contact with a photoconductor, which is an image carrier, for development. Has reached.
[0003]
On the other hand, non-contact developing devices that perform development without bringing the developer carrier into contact with the image carrier are attracting attention, and methods using the powder cloud method, jumping method, and electric field curtain (traveling wave electric field) are proposed. Has been. For example, a developing device using an electric field curtain includes the following. Japanese Patent Laid-Open No. 3-21967 discloses the following technique. Precharging means for precharging the developer transported by the developer carrying transport body and electric field curtain generating means for applying an electric field curtain on the developer carrying transport body are provided. As the preliminary charging means, for example, a preliminary charging roller made of foamed urethane is used. The preliminary charging roller is provided so as to be in contact with the developer carrying member, and a blade is provided so that the tip is in contact with the preliminary charging roller. Is provided. The preliminary charging roller preliminarily charges the developer by rubbing the developer with the developer carrying member and regulates the layer thickness of the developer.
[0004]
According to the above configuration, the developer can be uniformly charged to an appropriate charge amount, and the developer can be stably conveyed to the image carrier. As a result, it is avoided that the developer is scattered during conveyance or fogging is generated in the formed image.
[0005]
However, the above-described prior art causes the following problems. {Circle around (1)} When the pre-charging roller is brought into contact with the developer carrying member and rotated, the developer carrying member may be charged and the developer may not be stably conveyed. Nothing is said about this problem. {Circle around (2)} From the viewpoint of uniformizing the layer thickness of the developer supplied to the developer carrying carrier, it is shown that the preliminary charging roller is rotated in the direction opposite to the rotation direction of the developer carrying carrier. However, nothing is said about stably transporting the developer.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and an object of the present invention is to prevent the developer from being transported when a mechanism (electric field curtain) that transports the developer using a traveling wave electric field is used. Development device that eliminates various problems and enables smoother and more reliable transport of developer The It is to provide.
[0007]
[Means for Solving the Problems]
The present invention relates to a developer conveying means for conveying a developer by forming a traveling wave electric field by a multiphase voltage applied to a plurality of electrodes arranged at predetermined intervals in a substrate, and the developer conveying A substantially cylindrical supply means for rotatingly contacting the surface of the means and supplying the developer to the developer conveying means, and the developer conveying means has an electrostatic latent image on its surface. In the developing device disposed in the developing area facing the image carrier to be carried,
A light irradiating means for irradiating light, and the developer conveying means comprises a light irradiating means. Of light A developing device having a photoconductive layer in an area including at least a contact portion with a supply means.
[0008]
When the supply means rotates in contact with the developer conveying means, not only the developer conveyed on the surface but also the developer conveying means is charged, and as a result, the developer is prevented from being conveyed stably. There is a risk of being. On the other hand, according to the above configuration, a photoconductive layer is formed at least in the vicinity of the contact portion of the supply means, and the photoconductive layer is regularly irradiated with light by the light irradiation means, thereby developing charged. It becomes possible to neutralize the agent transporting means. Therefore, the developer can be transported more stably.
[0009]
Further, in the developing device, the photoconductive layer is formed of a material exhibiting bipolar conductivity.
[0010]
According to the above-described configuration, since the photoconductive layer exhibits bipolar conductivity, it is possible to reliably remove the charge regardless of the polarity of the triboelectric charge generated by the contact between the supply unit and the developer transport unit.
[0011]
The present invention is the developing device in which the electrode arranged in the region where the photoconductive layer is provided in the developer conveying means is a transparent electrode.
[0012]
According to the above configuration, since the electrode is a transparent electrode, the light is not shielded by the electrode even when the light irradiating means irradiates the light to the photoconductive layer. Thus, more uniform charge removal can be performed.
[0013]
Furthermore, the present invention is a developing device that applies a predetermined DC voltage to at least one of the plurality of electrodes in the supply unit and the developer transport unit when the light irradiation unit irradiates light.
[0014]
According to the above configuration, since the electric field formed in the photoconductive layer is strengthened, the charged developer conveying means can be discharged more quickly.
[0015]
In addition, the present invention is a developing device in which the light irradiation by the light irradiation unit is performed every time one developing operation is completed.
[0016]
According to the above configuration, the developer conveying means is neutralized every time when one developing operation is completed, that is, every time an image forming apparatus including the developing device of the present invention completes one image forming operation. . Therefore, the developer can be stably conveyed at every image forming operation, and the quality of the image formed by the image forming apparatus including the developer according to the present invention can be further improved.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the invention will be described.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a developing device and an image forming apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic diagram of a configuration of an image forming apparatus to which the exemplary embodiment is applied. FIG. 2 is a schematic diagram of a configuration of the developing device according to the first embodiment. FIG. 3 is a schematic diagram illustrating a configuration of a toner conveying member of the developing device according to the first embodiment. FIG. 4 is a waveform diagram of an example of a voltage waveform applied to the toner conveying member in the first embodiment. FIG. 5 is a schematic diagram illustrating a configuration of a toner conveying member of the developing device according to the first embodiment. FIG. 6 is a schematic diagram of another example of the developing device according to the first embodiment. FIG. 7 is a schematic diagram of a configuration of the developing device according to the second embodiment. FIG. 8 is an explanatory diagram of a contact portion between the toner conveying member and the supply member described in the second embodiment.
[0021]
In order to describe the developing device of the present invention, first, an example of an image forming apparatus to which the developing device of the present invention is applied will be described. As shown in FIG. 1, the image forming device includes a photoreceptor 2 and a charging member 3. , An exposure member 4, a developing device 1, a transfer member 5, a cleaning member 6, a charge removal member 7, and a fixing member 8. A charging member 3, an exposure member 4, a developing device 1, a transfer member 5, a cleaning member 6, and a charge removal member 7 are arranged in this order around the cylindrical photoreceptor 2. Of course, other members may be arranged. In addition, a sheet conveyance path for conveying a sheet as the recording medium 9 is disposed between the photosensitive member 2 and the transfer member 5. A fixing member 8 is disposed on the downstream side of the photosensitive member 2 when viewed from the conveyance direction of the sheet conveyance path.
[0022]
In the electrophotographic process, an electrostatic latent image corresponding to a document image or data from a host computer is formed on the photosensitive member 2 as an image carrier, and the electrostatic latent image is visualized by the developing device 1 and is printed on PPC paper or the like. The recording medium 9 is transferred to form an image.
[0023]
As shown in FIG. 1, the photoconductor 2 has a photoconductive layer 22 formed on a base material 21, and can be rotated from the charging member 3 according to the arrangement order of the respective members. First, the surface of the photosensitive member 2 is charged by the charging member 3 until it reaches a predetermined potential. The surface of the photosensitive member charged to a predetermined potential reaches the position of the exposure member 4 by the rotation of the photosensitive member 2 (rotation direction 2a). This exposure member 4 is a writing means, and writes an image on the surface of the photosensitive member charged by light such as a laser based on image information. As a result, an electrostatic latent image is formed on the photoreceptor 2. The surface of the photoreceptor on which the electrostatic latent image is formed reaches the position of the developing device 1 by the rotation of the photoreceptor 2.
[0024]
In the developing device 1, the electrostatic latent image on the surface of the photosensitive member is developed as a toner image by a developer such as the toner 17 conveyed on the toner conveying member (developer conveying means) 11. The surface of the photoreceptor carrying the toner image reaches the position of the transfer member 5 by the rotation of the photoreceptor 2. The transfer member 5 transfers the toner image on the surface of the photoconductor onto a recording medium 9 such as a sheet. The toner image transferred from the photoreceptor 2 onto the recording medium 9 is fixed on the paper by the fixing member 8.
[0025]
The surface of the photoconductor after the toner image is transferred reaches the position of the cleaning member 6 by the rotation of the photoconductor 2. The cleaning member 6 removes toner and paper dust remaining on the surface of the photoreceptor. The surface of the photosensitive member cleaned by the cleaning member 6 reaches the position of the charge eliminating member 7 by the rotation of the photosensitive member 2. The neutralizing member 7 removes the potential remaining on the surface of the photoreceptor. One image formation is completed by the series of operations described above.
[0026]
As the photoreceptor 2, for example, a metal drum such as aluminum is used as a base material 21, and a photoconductive layer 22 such as amorphous silicon (a-Si), selenium (Se), or an organic optical semiconductor (OPC) is a thin film on the outer peripheral surface thereof. Although the structure formed in the shape is mentioned, it is not specifically limited.
[0027]
Examples of the charging member 3 include, but are not limited to, a configuration of a corona charger, a charging roller, a charging brush, or the like made of a charging wire such as a tungsten wire, a metal shield plate, a grid plate, or the like.
[0028]
Examples of the exposure member 4 include a semiconductor laser and a light emitting diode, but are not particularly limited.
[0029]
Examples of the transfer member 5 include a corona transfer device, a transfer roller, and a transfer brush, but are not particularly limited.
[0030]
Examples of the cleaning member 6 include a cleaning blade, but are not particularly limited.
[0031]
The neutralization member 7 includes a neutralization lamp, but is not particularly limited.
[0032]
In FIG. 1, since a constant interval is provided between the toner conveying member 11 and the photosensitive member 2, in the present embodiment, the electrostatic latent image on the surface of the photosensitive member is developed in a non-contact manner. However, the present invention is not limited to this, and the toner carrying member 11 and the photosensitive member surface may be contacted to perform contact development.
[0033]
Embodiment 1 will be described. As shown in FIG. 2, the developing device 1 according to the present embodiment includes a toner transport member (developer transport unit) 11, a support member 12, a supply member 13, a recovery member 14, and a light irradiation member 15. The casing 16 and the toner mixing means 18 are provided. The toner transport member (developer transport means) 11, the support member 12, the supply member 13, the recovery member 14, and the light irradiation member 15 will be described later. The casing 16 accommodates toner (developer) 17 therein. The toner mixing means 18 is for mixing and stirring the toner 17 accommodated in the casing. In the present embodiment, a mixing paddle (MX paddle) is used and rotates in the rotation direction 18a. .
[0034]
The toner conveying member 11 has a belt shape that forms a substantially flat surface facing the developing area 2 b of the photoreceptor 2. In FIG. 2, the toner conveying member 11 has a belt shape, but the shape of the toner conveying member 11 is not limited to this, and may be, for example, a semicircular arc shape. In FIG. 2, the toner conveying member 11 is disposed so as to be slightly inclined with respect to the vertical direction of the developing device 1 and to be substantially parallel to the tangential direction of the developing region 2b on the surface of the photosensitive member. In addition, a support member 12 that holds the toner transport member 11 is provided on the surface opposite to the surface that transports the toner 17 so that the belt-shaped toner transport member 11 can maintain the above-described arrangement. Further, the photoconductive layer 111 is provided in a region including the contact portion with the supply member 13 in the toner conveying member 11, and the light irradiation member that irradiates the region that is the photoconductive layer 111 with light. (Light irradiation means) 15 is provided inside the support member 12.
[0035]
At the lower end (upstream side) of the toner transport member 11, a supply member (supply means) 13 for supplying the toner transported on the surface of the toner transport member is provided. On the other hand, a collecting member 14 that collects toner on the surface of the toner conveying member is provided at the upper end (downstream side) of the toner conveying member 11. In addition, a multiphase AC power source 19a and a developing bias power source 19b are connected to the toner conveying member 11 in series. Both the supply member 13 and the recovery member 14 are in contact with the surface of the belt-shaped toner conveying member 11 so as to be rotatable.
[0036]
The supply member 13 is for supplying the toner 17 accommodated in the casing 16 to the toner conveying member 11, and the material thereof is not particularly limited. For example, silicone, urethane, EPDM (ethylene -Propylene-diene-methylene copolymer) and the like, and foamed rubber. Further, conductivity may be imparted by adding carbon black or an ionic conductive agent (voltage application is also possible). A contact pressure between the supply member 13 and the toner conveying member 11 and a voltage value applied to the supply member 13 may be set to appropriate values, and the function of charging the toner 17 may be added to the supply member 13. Alternatively, for example, a thin blade (for example, the same material as that of the supply member 13 can be used) may be provided before the supply member 13 to charge the toner 17.
[0037]
The recovery member 14 is for recovering the toner that does not contribute to the development of the electrostatic latent image on the photosensitive member 2 and returning it to the developing device 1. The material of the recovery member 14 is not particularly limited. The same can be used.
[0038]
The support member 12 is for holding the belt-shaped toner conveying member 11 facing the developing region 2b of the photoreceptor 2, and the configuration thereof is not particularly limited. For example, a polycarbonate, an acrylic resin, etc. can be mentioned.
[0039]
As will be described later, the light irradiation member 15 may be any member that can neutralize the charged region by irradiating the region that is the photoconductive layer 111 in the toner conveying member 11 with light. Although not particularly limited, for example, an LED (Light Emitting Diode) is preferably used.
[0040]
The toner conveying member 11 conveys the toner 17 by the electric field curtain action. As shown in FIG. 3, a plurality of traveling wave generating electrodes 113 for generating the electric field curtain action are provided in the insulating layer (base material) 114. A plurality of sets are embedded successively one by one. A multi-phase AC voltage is applied to these electrodes 113 from a multi-phase AC power source 19a and a developing bias DC power source 19b for toner conveyance, whereby an electric field is generated in a direction parallel to the surface of the toner conveyance member 11. A curtain is generated, so that the toner 17 is conveyed to the developing region by the electric field curtain action.
[0041]
Specific examples of the toner conveying member 11 include, for example, a base material 114: polyimide (thickness 25 μm), traveling wave generating electrode 113: copper (thickness 18 μm), and surface protective layer 112: polyimide (thickness 25 μm). Can be mentioned. The traveling wave generating electrode 113 is a microelectrode having a width of 40 μm to 130 μm, and is arranged in parallel to each other with an interval of 100 dpi (dot per inch) to 300 dpi, that is, a pitch of about 254 μm to 85 μm.
[0042]
In the present embodiment, four microelectrodes {circle around (1)} to {circle around (4)} are taken as one set, and for example, four phases of voltage waveforms (having a phase shift) as shown in FIG. Although a traveling wave electric field is formed on the traveling wave generating electrode, the present invention is not limited to this, and a three-phase alternating voltage is applied to a set of three microelectrodes. It doesn't matter. In addition, as shown in FIG. 4, it is preferable that a bias voltage (development bias) is applied so that a development electric field is formed between the photoreceptor 2 and the toner conveying member 11. This point will be described later.
[0043]
The applied voltage waveform may be a sine wave or a trapezoidal wave, the voltage value range is preferably about 10 V to 1 kV, and the frequency range is preferably 100 Hz to 100 kHz. However, these voltage values and frequencies may be set appropriately depending on the shape of the traveling wave generating electrode 113, the conveyance speed of the toner 17, the material used for the toner 17, and the like, and are not particularly limited.
[0044]
In the present embodiment, as shown in FIGS. 2 and 5, the photoconductive layer 111 is provided in a fixed region of the toner transport member 11 including at least a contact portion with the supply member 13. 2 and 5, the photoconductive layer 111 is provided in a part of the surface protective layer 112 near the nip portion (portion where the supply member is in contact).
[0045]
In the conventional configuration (without the photoconductive layer), the pre-charging means (supply member) is in contact with the surface of the toner conveying member so as to be rotatable, so that not only the developer conveyed on the surface but also the toner conveying member. Invite people to become charged. When the toner conveying member is charged in this manner, a traveling wave electric field sufficient to convey the toner in that region is not formed, and there is a high possibility that the toner conveyance by the traveling wave is hindered, and the toner is stably stabilized. There was a possibility that the conveyance would be hindered.
[0046]
On the other hand, in the present embodiment, at least the vicinity of the nip where the supply member 13 and the toner conveying member 11 are in contact with each other is formed by the photoconductive layer 111. In particular, if the light irradiation member 15 is irradiated with light, the charged toner transport member 11 can be neutralized. Therefore, the developer (toner) 17 can be transported more stably.
[0047]
The photoconductive layer 111 at this time is not particularly limited as long as it shows conductivity when irradiated with light. Specifically, as a material used for the photoconductive layer 111, for example, an organic semiconductor composed of a carrier generation layer and a carrier transport layer, hydrogenated amorphous silicon, or the like is preferably used.
[0048]
A specific example of an organic semiconductor will be described. First, examples of the carrier generation layer include a configuration in which a charge generation material is added to at least a binder resin. In addition, various additives such as a chemical sensitizer and an optical sensitizer may be added.
[0049]
Examples of the charge generating material include bisazo compounds such as chlordian blue; polycyclic quinone compounds such as dibromoanthanthrone; perylene compounds; quinacridone compounds; phthalocyanine compounds; Each of these materials may be used alone or in combination of two or more.
[0050]
The binder resin of the carrier generation layer is not particularly limited, but for example, polyvinyl butyral resin, polycarbonate resin, polyester resin, polyarylate resin, phenoxy resin, epoxy resin, polystyrene resin, polymethyl methacrylate resin, polyvinyl chloride Examples thereof include resins and silicone resins.
[0051]
Examples of the chemical sensitizer include an electron accepting material, and examples of the optical sensitizer include various dyes. The electron-accepting material is not particularly limited. For example, cyano compounds such as tetracyanoethylene and 7,7,8,8-tetracyanoquinodimethane; quinones such as anthraquinone and p-benzoquinone; 2 , 4,7-trinitrofluorenone and the like nitro compounds. The dye as the optical sensitizer is not particularly limited, and examples thereof include xanthene dyes; thiazine dyes; triphenyl meta dyes.
[0052]
Next, as the carrier transport layer, a configuration in which a charge transport material is added to at least the binder resin can be exemplified.
[0053]
Examples of the charge transport material include polymer compounds such as polyvinyl carbazole and polysilane; low molecular compounds such as hydranzone compounds, oxadiazole compounds, stilbene compounds, and triphenylmethane compounds.
[0054]
The binder resin for the carrier transport layer is not particularly limited, and examples thereof include polycarbonate resin, polyester resin, phenoxy resin, epoxy resin, polystyrene resin, polymethyl methacrylate resin, polyvinyl chloride resin, and silicone resin. .
[0055]
Next, hydrogenated amorphous silicon (a-Si: H) will be described. Hydrogenated amorphous silicon is added with intrinsic hydrogenated amorphous silicon produced by the usual plasma chemical vapor deposition (plasma CVD method: Chemical Vapor Deposition) and a small amount (several ppm to several tens of ppm) of boron (B). And boron-doped hydrogenated amorphous silicon.
[0056]
The volume resistivity ρ of this hydrogenated amorphous silicon is 10 ⁹ Ω · cm or more 10 ¹¹ It is preferably Ω · cm or less, but is not particularly limited. The volume resistivity ρ can be adjusted by appropriately setting the substrate temperature, pressure, gas flow rate, high-frequency power, and the like at the time of creation by the plasma CVD method.
[0057]
In the present embodiment, any of the above materials may be used as the photoconductive layer, but hydrogenated amorphous silicon is even more preferable. Hydrogenated amorphous silicon is preferable because it has advantages such as being able to remove electricity relatively easily without disturbing the traveling wave electric field, showing bipolar conductivity, and having a hard surface hardness to prevent wear of the surface protective layer. .
[0058]
In this embodiment, since the frictional charge generated by the contact between the supply member and the toner conveying member can be both positive and negative, a material that exhibits conductivity of both polarities than a material that exhibits conductivity of only one polarity. Then, even if the charging polarity changes, the toner conveying member can be reliably discharged. That is, the photoconductive layer in this embodiment is not limited to hydrogenated amorphous silicon, and it is preferable to use a material exhibiting bipolar conductivity.
[0059]
Further, the traveling wave generating electrodes arranged in the region where the photoconductive layer is provided are preferably formed of transparent electrodes. This prevents light from being shielded by the electrodes when the light irradiation member irradiates the photoconductive layer with light. Therefore, more uniform charge removal can be performed by uniformly irradiating the entire photoconductive layer with light.
[0060]
Although it does not specifically limit as a transparent electrode, For example, ITO (Indium Tin Oxide), tin oxide (SnO) ₂ ), Indium oxide (In ₂ O ₃ ) And the like. The method for forming the transparent electrode is not particularly limited, but for example, an electron beam evaporation method is preferably used.
[0061]
In the configuration shown in FIGS. 2 and 5, the photoconductive layer is provided only at the nip portion between the supply member and the toner conveying member. However, the present embodiment is not limited to this and is shown in FIG. As described above, the photoconductive layer 111 may be provided over the entire surface protective layer of the toner conveying member 11.
[0062]
At this time, a method of rotating the light irradiation member 15 (rotation direction 15a) is preferably used to irradiate the entire area of the toner conveying member. When rotating the light irradiation member 15, it is preferable to adjust the current value according to the distance between the light irradiation member 15 and the photoconductive layer 111 in order to make the light irradiation intensity the same. As a result, the charge removal can be performed more reliably.
[0063]
In the present embodiment, at the time when the light irradiation member 15 irradiates light, a bias voltage (predetermined DC voltage) is applied to at least one of the supply member 13 and the traveling wave generating electrode 113 of the toner conveying member 11. ) Is preferably applied.
[0064]
For example, in the present embodiment, for the toner conveying member 11, four microelectrodes (1) to (4) are set as one set, and for each of these sets of electrodes, for example, a voltage waveform as shown in FIG. 4 is applied to form a traveling wave electric field on the traveling wave generating electrode. As shown in FIG. 4, there is a developing electric field between the photosensitive member 2 and the toner conveying member 11. It is preferable that a developing bias voltage (predetermined DC voltage) is applied so as to be formed (at this time, the supply member 13 is applied with a ground potential or a DC voltage having a polarity opposite to that of the developing bias power source 19b. ). As a result, the electric field formed in the photoconductive layer 111 can be strengthened, so that the charged toner conveying member 11 can be discharged more quickly.
[0065]
Conversely, a voltage may be applied to the supply member 13, and a voltage having a polarity opposite to that applied to the ground potential or the supply member 13 may be applied to each pair of electrodes of the toner transport member 11.
[0066]
The light irradiation timing by the light irradiation member 15 in the present embodiment is not particularly limited, but a more preferable timing is every time when one development operation is completed. That is, the end of one developing operation coincides with the timing at which the image forming apparatus including the developing device 1 of the present embodiment completes one image forming operation. Therefore, since the toner transport member 11 is neutralized every time the image forming operation is performed, an undesired charged state in the toner transport member 11 is canceled every time the image forming operation is performed. Therefore, it is possible to always stably convey the toner for each image forming operation, and the quality of the formed image can be further improved.
[0067]
Embodiment 2 will be described. In the present embodiment, the toner 17 can be transported more smoothly by setting the rotation direction 13a of the supply member and the toner transport direction 11a to the same direction (forward direction). As shown in FIG. 7, the developing device 1 according to the present embodiment has substantially the same configuration except that the photoconductive layer and the light irradiation member in the first embodiment are not provided.
[0068]
Here, it will be described that the toner is supplied to the toner conveying member by rotating the supply member in contact with the surface of the belt-shaped toner conveying member. As shown in FIGS. 9 and 10, when the rotation direction of the supply member is opposite to that in the nip portion 13 b with respect to the toner conveyance direction, toner accumulation occurs on the outlet side of the nip portion. The occurrence of such toner accumulation indicates that the toner is not smoothly conveyed, and further, since this toner accumulation situation also becomes a barrier for toner conveyance, smooth toner conveyance becomes even more difficult. .
[0069]
Therefore, in the present embodiment, the rotation direction at the nip portion of the supply member, that is, the rotation direction of the supply member 13 on the surface in contact with the toner conveyance member 11 is the forward direction, that is, the same as the toner conveyance direction. The direction. As a result, as shown in FIG. 8, the toner is blocked by the supply member at the nip portion and the developer is prevented from staying, so that the developer can be transported stably.
[0070]
As the supply member 13, the same member as in the first embodiment is used, but the rotation speed at this time is preferably several mm / s to several tens mm / s. Further, the contact pressure (nip pressure) between the surface of the toner conveying member 11 and the supply member 13 at the nip is preferably several gf / mm. The rotation speed and contact pressure of the supply member 13 are set to appropriate values according to the materials used for the supply member 13 and the toner transport member 11 and the toner transport speed (as described in the first embodiment, the toner transport member 11 is charged). To prevent the toner from accumulating and preventing the toner from accumulating. By setting the supply member in this way, it is possible to effectively avoid toner accumulation.
[0071]
Furthermore, the configuration in the second embodiment, that is, the configuration in which the rotation direction of the supply member is the same as the toner transport direction is the same as the configuration in the first embodiment, that is, a photoconductive layer is provided in the nip portion and the charge is eliminated by light irradiation. It is applicable also to the structure to do. As a result, the formation of the traveling wave is not hindered by the configuration of the first embodiment, and the toner is more smoothly conveyed, and further, the toner does not accumulate due to the supply member, so that the toner is even more smoothly conveyed. become. Therefore, in the developing device according to the present invention, it is very preferable that not only one of Embodiments 1 and 2 but also both configurations are adopted. The image forming apparatus including the developing device can be similarly applied to other types of image forming apparatuses such as processes other than the electrophotographic process, such as an ion flow method and a toner jet method.
[0072]
【The invention's effect】
According to the present invention, when a mechanism (electric field curtain) for transporting a developer using a traveling wave electric field is used, various problems that hinder the transport of the developer are solved, and development is performed more smoothly and reliably. Development device that enables transport of the agent The Obtainable.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a configuration of an image forming apparatus to which an embodiment is applied.
FIG. 2 is a schematic diagram of a configuration of a developing device according to the first embodiment.
FIG. 3 is a schematic cross-sectional view of a toner conveying member of the developing device according to the first embodiment.
4 is a waveform diagram showing an example of a voltage waveform applied to a toner conveying member in Embodiment 1. FIG.
FIG. 5 is a schematic front view of a toner conveying member of the developing device according to the first embodiment.
FIG. 6 is a schematic diagram of another example of the developing device according to the first embodiment.
FIG. 7 is a schematic diagram of a configuration of a developing device according to a second embodiment.
FIG. 8 is an explanatory diagram of a contact portion between a toner conveying member and a supply member described in a second embodiment.
FIG. 9 is a schematic front view of a toner transport member of an example developing device in which toner accumulation occurs.
FIG. 10 is an explanatory diagram of a toner reservoir at a contact portion between a toner conveying member and a supply member.
[Explanation of symbols]
1 Developer
11 Toner conveying member
11a Toner transport direction
111 Photoconductive layer
112 Surface protective layer
113 Traveling wave generating electrode
114 substrate
12 Support members
13 Supply members
13a Rotation direction
13b Nip part
14 Collection member
15 Light irradiation member
16 Casing
17 Toner
18 MX paddle
19a Multiphase AC power supply
19b Development bias DC power supply
2 Photoconductor
2a Direction of rotation
2b Development area
21 Base material
22 Photoconductive layer
3 Charging member
4 Exposure members
5 Transfer member
6 Cleaning member
7 Static elimination member
8 Fixing member
9 Recording media

Claims (5)

  A developer conveying means for conveying a developer by forming a traveling wave electric field by a multiphase voltage applied to a plurality of electrodes arranged at predetermined intervals in the substrate; and a surface of the developer conveying means A substantially cylindrical supply means for contacting the developer and supplying the developer to the developer conveying means, and the developer conveying means carries an electrostatic latent image on its surface. In the developing device disposed in the developing region facing the body, the developing device includes a light irradiation means for irradiating light, and the developer conveying means includes a photoconductive layer irradiated with light from the light irradiation means. A developing device having at least a region including a contact portion with the supply means.   The developing device according to claim 1, wherein the photoconductive layer is formed of a material exhibiting bipolar conductivity.   3. The developing device according to claim 1, wherein the electrode arranged in the region where the photoconductive layer is provided in the developer conveying means is a transparent electrode. At the time of irradiating light by said light irradiating means, among the plurality of electrodes in the supply means and the developer conveying unit, to at least one, in any one of claims 1 to 3 for applying a predetermined DC voltage The developing device described. Irradiation of light by the light irradiation means, a developing device according to one any one of claims 1 to 4 is performed for each end of the developing operation.

Images