JP4404082B2 - Developer electric field transfer device, developer supply device, and image forming apparatus - Google Patents

Description

  The present invention relates to a developer electric field transport device, a developer supply device, and an image forming apparatus.

  In an image forming apparatus, a number of mechanisms for transporting a developer (dry developer or dry toner) using a traveling wave electric field have been conventionally known (for example, Japanese Patent Laid-Open No. 63-13074, Japanese Patent Publication No. 5-137). No. 31146, JP-A No. 2002-351218, JP-A No. 2003-15417, JP-A No. 2004-157259, JP-A No. 2004-340996, JP-A No. 2005-275127, etc.). In such a mechanism, a large number of linear electrodes are arranged in a row on an insulating substrate.

According to the above-described configuration, a traveling wave electric field is formed by sequentially applying a multiphase AC voltage to a large number of the linear electrodes. The charged developer is conveyed in a predetermined direction by the action of the traveling wave electric field.
JP 63-13074 A Japanese Patent Publication No. 5-31146 JP 2002-351218 A JP 2003-15417 A JP 2004-157259 A JP 2004-340996 A JP 2005-275127 A JP-A-4-318575

  In the image forming apparatus as described above, further improvement in image quality is required. For this purpose, it is necessary to suppress variations in the developer transport amount in the width direction (main scanning direction) perpendicular to the predetermined direction.

  The present invention has been made to solve such problems. That is, an object of the present invention is provided with a developer electric field transport device capable of suppressing variation in the width direction (main scanning direction) of the developer transport amount due to a traveling wave electric field, and the developer electric field transport device. It is an object to provide a developer supply device and an image forming apparatus.

  (1) An image forming apparatus of the present invention includes an electrostatic latent image carrier and a developer supply device.

  The electrostatic latent image carrier has a latent image forming surface. This latent image forming surface is formed in parallel with a predetermined main scanning direction. The latent image forming surface is configured such that an electrostatic latent image can be formed by a potential distribution. The electrostatic latent image carrier is configured such that the latent image forming surface can move along a sub-scanning direction orthogonal to the main scanning direction.

  The developer supply device is disposed to face the electrostatic latent image carrier. The developer supply device is configured to supply the developer to the latent image forming surface in a charged state.

  In the image forming apparatus of the present invention, the developer supply device includes a plurality of transport electrodes, an electrode support member, and an electrode covering member.

  The transport electrode is configured to have a longitudinal direction that intersects the sub-scanning direction. The transport electrodes are arranged along the sub-scanning direction. These transport electrodes are configured and arranged so as to be able to transport the developer in a predetermined developer transport direction when a traveling wave voltage is applied.

  The electrode support member is configured to support the transport electrode. That is, the transport electrode is supported on the surface of the electrode support member.

  The electrode covering member is formed to cover the surface of the electrode support member and the transport electrode. The electrode covering member has a developer transport surface. The developer transport surface is a surface that is parallel to the main scanning direction and faces the latent image forming surface.

  In the developer supply apparatus, the first portion and the second portion are provided so as to be aligned along the longitudinal direction of the transport electrode. Here, in the first part, the first part and the first part are different so that the structure between the surface of the electrode support member and the developer transport surface is different from the second part. Two parts are configured.

  Specifically, the electrode covering member may be formed so that the relative permittivity differs between the first portion and the second portion.

  Alternatively, the electrode covering member may be formed so that the thickness differs between the first portion and the second portion.

  Alternatively, the image forming apparatus further includes an intermediate layer formed between the electrode covering member and the transport electrode, and the intermediate layer includes the first portion and the second portion, They can be formed so that their relative dielectric constants are different.

  Alternatively, the image forming apparatus further includes an intermediate layer formed between the thinner part of the electrode covering member and the transport electrode, and the intermediate layer is compared with the electrode covering member. They can be formed with different dielectric constants.

  Alternatively, the first portion and the second portion may be arranged in stripes along the sub-scanning direction in plan view.

  Alternatively, the first part and the second part may be formed in a polygonal shape arranged so as to be adjacent to each other in plan view.

  Alternatively, the first portion and the second portion may be arranged in an oblique stripe shape that intersects the sub-scanning direction in plan view.

  Alternatively, either the first portion or the second portion is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view, and the first portion The other of the portion or the second portion different from the one may be configured by a portion surrounded by the first stripe and the second stripe in a plan view.

  Alternatively, the first part and the second part may be randomly arranged.

  Alternatively, the transport electrode may be formed so that the thickness is different between the first portion and the second portion.

  Alternatively, a protrusion may be formed at a position corresponding to the first portion of the transport electrode.

  The image forming apparatus of the present invention having such a configuration operates as follows during image formation.

  The electrostatic latent image based on the potential distribution is formed on the latent image forming surface of the electrostatic latent image carrier. The latent image forming surface on which the electrostatic latent image is formed moves along the sub-scanning direction.

  A predetermined traveling wave voltage is applied to the plurality of transport electrodes in the developer transport body provided in the developer supply apparatus. This voltage generates a predetermined traveling-wave electric field on the developer transport surface. By this electric field, the charged developer moves on the developer transport surface along the developer transport direction.

  The latent image forming surface and the developer transport surface are surfaces parallel to the main scanning direction. Therefore, in the vicinity of the closest position where the distance between the latent image forming surface and the developer conveying surface is the shortest, the latent image forming surface and the developer conveying surface are opposed to each other in a parallel state. Can do. The electrostatic latent image is developed in the vicinity of the closest position by the charged developer conveyed on the developer conveyance body.

  Here, in the image forming apparatus of the present invention, the surface of the electrode support member and the developer are formed by the first portion and the second portion that are aligned along the longitudinal direction of the transport electrode. The structure between the transfer surface is different. Then, the state (intensity and / or direction) of the electric field may be different between the first portion and the second portion on the developer transport surface.

  As a result, in the vicinity of the boundary between the first portion and the second portion, a component along the longitudinal direction can be generated in the traveling wave electric field generated on the developer transport surface. Since the longitudinal direction intersects the sub-scanning direction, the above-described component intersects the sub-scanning direction. That is, such a component can be along the main scanning direction.

  Therefore, the charged developer can also move in the direction along the longitudinal direction (the main scanning direction) on the developer transport surface. In other words, the charged developer can move toward the closest position while meandering on the developer transport surface.

  According to this configuration, for example, even if variation occurs in the amount of the developer supplied to the most upstream portion of the developer transport surface in the developer transport direction due to the occurrence of aggregation of the developer, the development By the meandering of the agent as described above, the variation in the transport amount in the width direction (the direction perpendicular to the developer transport direction and along the longitudinal direction) can be effectively eliminated.

  Therefore, according to this configuration, variations in the main scanning direction of the developer transport amount due to the traveling wave electric field on the developer transport surface can be suppressed. Accordingly, the charged developer can be supplied to the latent image forming surface in a state where unevenness in the supply amount in the main scanning direction is suppressed as much as possible. Therefore, density unevenness in the width direction (the main scanning direction) of the image by the developer can be suppressed as much as possible.

  (2) The developer supply device of the present invention is configured so that the developer can be supplied along a predetermined developer transport direction in a charged state with respect to the developer carrying surface of the developer carrying member. .

  Here, the developer carrier may be arranged to face the developer supply device. The developer carrier has the developer carrying surface.

  The developer carrying surface is a surface parallel to a predetermined main scanning direction and can carry the developer. The developer carrying surface can move along a sub-scanning direction orthogonal to the main scanning direction.

  Specifically, as the developer carrying member, for example, an electrostatic latent image carrying member configured to form an electrostatic latent image by a potential distribution can be used. In this case, the developer carrying surface is constituted by a latent image forming surface. The latent image forming surface is a peripheral surface of the electrostatic latent image carrier. The latent image forming surface is configured such that the electrostatic latent image can be formed.

  Alternatively, as the developer carrier, for example, a recording medium (paper or the like) conveyed along the sub-scanning direction can be used. In this case, the developer carrying surface is constituted by the surface (recorded surface) of the recording medium.

  Alternatively, as the developer carrying member, for example, a roller, a sleeve, or a belt-like member (a developing roller, a developing sleeve, an intermediate transfer belt, or the like) can be used. These members are arranged so as to face the recording medium and the electrostatic latent image carrier, for example. These members are configured and arranged so that the developer can be transferred onto the recording medium or the electrostatic latent image carrier.

  The developer supply device of the present invention includes a plurality of transport electrodes, an electrode support member, and an electrode covering member.

  The transport electrode is configured to have a longitudinal direction that intersects the sub-scanning direction. The transport electrodes are arranged along the sub-scanning direction. These transport electrodes are configured and arranged so as to be able to transport the developer in a predetermined developer transport direction when a traveling wave voltage is applied.

  The electrode support member is configured to support the transport electrode. That is, the transport electrode is supported on the surface of the electrode support member.

  The electrode covering member is formed to cover the surface of the electrode support member and the transport electrode. The electrode covering member has a developer transport surface. The developer transport surface is a surface that is parallel to the main scanning direction and faces the developer carrying surface.

  In the developer supply apparatus, the first portion and the second portion are provided so as to be aligned along the longitudinal direction of the transport electrode. Here, in the first part, the first part and the first part are different so that the structure between the surface of the electrode support member and the developer transport surface is different from the second part. Two parts are configured.

  Specifically, the electrode covering member may be formed so that the relative permittivity differs between the first portion and the second portion.

  Alternatively, the electrode covering member may be formed so that the thickness differs between the first portion and the second portion.

  Alternatively, the developer supply device further includes an intermediate layer formed between the electrode covering member and the transport electrode, and the intermediate layer includes the first portion and the second portion. The dielectric constant may be different.

  Alternatively, the developer supply apparatus further includes an intermediate layer formed between the thinner portion of the electrode covering member and the transport electrode, and the intermediate layer includes the electrode covering member. It can be formed so that the relative dielectric constant is different.

  Alternatively, the first portion and the second portion may be arranged in stripes along the sub-scanning direction in plan view.

  Alternatively, the first part and the second part may be formed in a polygonal shape arranged so as to be adjacent to each other in plan view.

  Alternatively, the first portion and the second portion may be arranged in an oblique stripe shape that intersects the sub-scanning direction in plan view.

  Alternatively, either the first portion or the second portion is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view, and the first portion The other of the portion or the second portion different from the one may be configured by a portion surrounded by the first stripe and the second stripe in a plan view.

  Alternatively, the first part and the second part may be randomly arranged.

  Alternatively, the transport electrode may be formed so that the thickness is different between the first portion and the second portion.

  Alternatively, a protrusion may be formed at a position corresponding to the first portion of the transport electrode.

  The image forming operation using the developer supply apparatus of the present invention having such a configuration is performed as follows.

  The developer transport surface of the developer transport body in the developer supply device, and the developer support surface of the developer support body (disposed to face the developer supply device) are the main scanning. A plane parallel to the direction.

  Therefore, in the vicinity of the closest position where the distance between the developer carrying surface and the developer carrying surface is the shortest, the developer carrying surface and the developer carrying surface face each other in a parallel state. Can do.

  The developer carrying surface of the developer carrying body moves along the sub-scanning direction. On the other hand, the charged developer is transported along the developer transport direction on the developer transport surface of the developer transport body.

  Accordingly, the charged developer is supplied to the developer carrying surface in the vicinity of the closest position. The charged developer can be carried on the developer carrying surface.

  The transport of the charged developer on the developer carrying surface as described above is performed as follows.

  A predetermined traveling-wave voltage is applied to the plurality of transport electrodes in the developer transport body. This voltage generates a predetermined traveling-wave electric field on the developer transport surface. By this electric field, the charged developer moves on the developer transport surface along the developer transport direction.

  Here, in the developer supply device of the present invention, the surface of the electrode support member and the development are formed by the first portion and the second portion that are aligned along the longitudinal direction of the transport electrode. The structure between the agent conveying surface is different. Then, the state (intensity and / or direction) of the electric field may be different between the first portion and the second portion on the developer transport surface.

  As a result, in the vicinity of the boundary between the first part and the second part, the above-mentioned traveling wave electric field generated on the developer transport surface is subjected to a component along the longitudinal direction, that is, the main part. Components along the scanning direction can occur. Therefore, the charged developer can also move in the direction along the longitudinal direction (the main scanning direction) on the developer transport surface. In other words, the charged developer can move toward the closest position while meandering on the developer transport surface.

  According to this configuration, variation in the main scanning direction of the developer transport amount due to the traveling wave electric field on the developer transport surface can be suppressed. Therefore, the charged developer can be supplied to the developer carrying surface in a state where unevenness in the supply amount in the main scanning direction is suppressed as much as possible.

  (3) The developer electric field transport device of the present invention is configured to transport a charged developer along a predetermined developer transport direction by an electric field. The developer electric field transport device is disposed so as to face the developer carrier.

  The developer carrying member has a developer carrying surface. The developer carrying surface is a surface of the developer carrying body, on which the developer can be carried. The developer carrying surface is formed in parallel with a predetermined main scanning direction.

  The developer carrying surface can move along a predetermined moving direction. This moving direction can be set to be parallel to the sub-scanning direction orthogonal to the main scanning direction.

  Specifically, as the developer carrying member, for example, an electrostatic latent image carrying member configured to form an electrostatic latent image by a potential distribution can be used. In this case, the developer carrying surface is constituted by a latent image forming surface. The latent image forming surface is a peripheral surface of the electrostatic latent image carrier, on which the electrostatic latent image is formed.

  Alternatively, as the developer carrier, for example, a recording medium (paper or the like) conveyed along the sub-scanning direction can be used. In this case, the developer carrying surface is constituted by the surface (recorded surface) of the recording medium.

  Alternatively, as the developer carrying member, for example, a roller, a sleeve, or a belt-like member (a developing roller, a developing sleeve, an intermediate transfer belt, or the like) can be used. These members are arranged so as to face the recording medium and the electrostatic latent image carrier. These members are configured and arranged so that the developer can be transferred onto the recording medium or the electrostatic latent image carrier.

  The developer electric field transport device of the present invention includes a plurality of transport electrodes, an electrode support member, and an electrode covering member.

  The transport electrode is configured to have a longitudinal direction that intersects the sub-scanning direction. The transport electrodes are arranged along the sub-scanning direction. These transport electrodes are configured and arranged so as to be able to transport the developer in a predetermined developer transport direction when a traveling wave voltage is applied.

  The electrode support member is configured to support the transport electrode. That is, the transport electrode is supported on the surface of the electrode support member.

  The electrode covering member is formed to cover the surface of the electrode support member and the transport electrode. The electrode covering member has a developer transport surface. The developer transport surface is a surface that is parallel to the main scanning direction and faces the developer carrying surface.

  In the developer electric field transport device, the first portion and the second portion are provided so as to be aligned along the longitudinal direction of the transport electrode. Here, in the first part, the first part and the first part are different so that the structure between the surface of the electrode support member and the developer transport surface is different from the second part. Two parts are configured.

  Specifically, the electrode covering member may be formed so that the relative permittivity differs between the first portion and the second portion.

  Alternatively, the electrode covering member may be formed so that the thickness differs between the first portion and the second portion.

  Alternatively, the developer electric field transport device further includes an intermediate layer formed between the electrode covering member and the transport electrode, and the intermediate layer includes the first portion and the second portion. Thus, the dielectric constants may be different.

  Alternatively, the developer electric field transport device further includes an intermediate layer formed between a portion having a smaller thickness in the electrode covering member and the transport electrode, and the intermediate layer includes the electrode covering member. And having a relative dielectric constant different from each other.

  Alternatively, the first portion and the second portion may be arranged in stripes along the sub-scanning direction in plan view.

  Alternatively, the first part and the second part may be formed in a polygonal shape arranged so as to be adjacent to each other in plan view.

  Alternatively, the first portion and the second portion may be arranged in an oblique stripe shape that intersects the sub-scanning direction in plan view.

  Alternatively, either the first portion or the second portion is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view, and the first portion The other of the portion or the second portion different from the one may be configured by a portion surrounded by the first stripe and the second stripe in a plan view.

  Alternatively, the first part and the second part may be randomly arranged.

  Alternatively, the transport electrode may be formed so that the thickness is different between the first portion and the second portion.

  Alternatively, a protrusion may be formed at a position corresponding to the first portion of the transport electrode.

  The image forming operation using the developer electric field transport apparatus of the present invention having such a configuration is performed as follows.

  The developer carrying surface in the developer electric field transport device and the developer carrying surface in the developer carrying body arranged to face the developer electric field transport device are surfaces parallel to the main scanning direction. is there.

  Therefore, in the vicinity of the closest position where the distance between the developer electric field transport device and the developer carrying member (the distance between the developer carrying surface and the developer carrying surface) is the shortest, The developer carrying surface and the developer transport surface can face each other in a parallel state.

  The developer carrying surface of the developer carrying body moves along the sub-scanning direction. On the other hand, the charged developer is transported along the developer transport direction on the developer transport surface of the developer transport body in the developer electric field transport device.

  Accordingly, the charged developer is supplied from the developer transport surface of the developer electric field transport device to the developer bearing surface of the developer carrier near the closest position. . The charged developer can be carried on the developer carrying surface.

  The transport of the charged developer on the developer carrying surface as described above is performed as follows.

  A predetermined traveling-wave voltage is applied to the plurality of transport electrodes in the developer transport body. This voltage generates a predetermined traveling-wave electric field on the developer transport surface. By this electric field, the charged developer moves on the developer transport surface along the developer transport direction.

  Here, in the developer electric field transport device of the present invention, the first portion and the second portion that are arranged along the longitudinal direction of the transport electrode, and the surface of the electrode support member and the surface The structure between the developer conveying surface is different. Then, the state (intensity and / or direction) of the electric field may be different between the first portion and the second portion on the developer transport surface.

  As a result, in the vicinity of the boundary between the first part and the second part, the above-mentioned traveling wave electric field generated on the developer transport surface is subjected to a component along the longitudinal direction, that is, the main part. Components along the scanning direction can occur. Therefore, the charged developer can move along the developer transport direction (toward the closest position) while meandering on the developer transport surface.

  According to this configuration, variation in the main scanning direction of the developer transport amount due to the traveling wave electric field on the developer transport surface can be suppressed.

  Hereinafter, embodiments of the present invention (embodiments that the applicant considers best at the time of filing of the present application) will be described with reference to the drawings.

<Overall configuration of laser printer>
FIG. 1 is a side view showing a schematic configuration of a laser printer 1 which is an embodiment of an image forming apparatus of the present invention.

  Referring to FIG. 1, the laser printer 1 includes a paper transport mechanism 2, a photosensitive drum 3, a charger 4, a scanner unit 5, and a toner supply device 6.

  Sheet-like paper P is stored in a stacked state in a paper feed tray (not shown) provided in the laser printer 1. The paper transport mechanism 2 is configured to transport the paper P along a predetermined paper transport path.

  On the peripheral surface of the photosensitive drum 3 as the electrostatic latent image carrier, developer image carrier, and developer carrier of the present invention, the latent image forming surface, developer image bearing surface, and developer of the present invention are provided. A latent image forming surface LS is formed as an agent carrying surface.

  The latent image forming surface LS is formed as a cylindrical surface parallel to the main scanning direction (z-axis direction in the figure). The latent image forming surface LS is configured such that an electrostatic latent image LI based on a potential distribution can be formed.

  The photosensitive drum 3 is configured to be rotationally driven around the central axis C in a direction indicated by an arrow in the drawing. That is, the photosensitive drum 3 is configured such that the latent image forming surface LS can move along a predetermined movement direction, that is, a sub-scanning direction orthogonal to the main scanning direction.

  The “sub-scanning direction” is an arbitrary direction orthogonal to the main scanning direction. Usually, the sub-scanning direction is a direction intersecting the vertical line. That is, the sub-scanning direction is a direction along the front-rear direction of the laser printer 1 (direction perpendicular to the paper width direction and the height direction: the x-axis direction in the drawing).

  The charger 4 is disposed so as to face the latent image forming surface LS. The charger 4 is a corotron type or scorotron type charger, and is configured so that the latent image forming surface LS can be uniformly positively charged.

  The scanner unit 5 is configured to generate a laser beam LB modulated based on image data. In addition, the scanner unit 5 causes the generated laser beam LB to be positioned on the latent image forming surface LS and to be rotated in the direction of rotation of the photosensitive drum 3 relative to the charger 4 (direction indicated by an arrow in FIG. 1). : It is configured to form an image (exposure) at a downstream position (scan position SP) in the clockwise direction in the figure. Further, the scanner unit 5 is configured to move (scan) the position at which the laser beam LB is formed on the latent image forming surface LS at a constant speed along the main scanning direction.

  The toner supply device 6 as the developer supply device of the present invention is disposed so as to face the photosensitive drum 3. The toner supply device 6 is configured to supply positively charged toner, which is a fine particle dry developer (powder developer), to the latent image forming surface LS in a charged state. The detailed configuration of the toner supply device 6 will be described later.

<Configuration of each part of the laser printer>
Next, a specific configuration of each part of the laser printer 1 will be described.

<< paper transport mechanism >>
The sheet transport mechanism 2 includes a pair of registration rollers 21 and a transfer roller 22.

  The registration roller 21 is configured so that the paper P can be sent out between the photosensitive drum 3 and the transfer roller 22 at a predetermined timing.

  The transfer roller 22 is disposed so as to face the latent image forming surface LS, which is the outer peripheral surface of the photosensitive drum 3, at the transfer position TP with the paper P interposed therebetween. Further, the transfer roller 22 is configured to be rotationally driven in a direction (counterclockwise) indicated by an arrow in the drawing.

  The transfer roller 22 is connected to a bias power supply circuit (not shown). That is, a predetermined transfer bias voltage for transferring the toner (developer) adhered on the latent image forming surface LS to the paper P is applied between the transfer roller 22 and the photosensitive drum 3. Yes.

<< Photosensitive drum >>
FIG. 2 is an enlarged side sectional view of a portion where the photosensitive drum 3 and the toner supply device 6 shown in FIG. 1 face each other.

  Referring to FIG. 2, the photosensitive drum 3 includes a drum body 31 and a photosensitive layer 32.

  The drum body 31 is a cylindrical member having a central axis C parallel to the z axis, and is made of a metal such as aluminum. The drum body 31 is grounded.

  The photosensitive layer 32 is provided so as to cover the outer periphery of the drum body 31. The photosensitive layer 32 is composed of a positively chargeable photoconductive layer that exhibits electron conductivity when exposed to laser light having a predetermined wavelength.

  The latent image forming surface LS is configured by the outer peripheral surface of the photosensitive layer 32. That is, after being uniformly positively charged by the charger 4 (see FIG. 1), the laser beam LB is scanned at the scan position SP, thereby forming an electrostatic latent image LI having a positive charge pattern. Thus, the latent image forming surface LS (photosensitive layer 32) is configured.

<< Toner Supply Device >>
A toner box 61 forming a casing of the toner supply device 6 is a box-shaped member, and is configured to store toner T as a fine particle dry developer therein. In this embodiment, the toner T is a positively chargeable, non-magnetic one-component black toner.

  A top plate 61 a in the toner box 61 is disposed so as to be close to the photosensitive drum 3. A toner passage hole 61a1 is formed in the top plate 61a. The toner passage hole 61a1 is formed at a position where the top plate 61a and the photosensitive layer 32 are close to each other.

  The toner passage hole 61a1 has a long side having a length substantially the same as the width of the photosensitive layer 32 in the main scanning direction (z-axis direction in the drawing) in plan view and the sub-scanning direction (x-axis direction in the drawing). It is formed in a rectangular shape having a short side parallel to the. The toner passage hole 61a1 is formed as a through hole through which the toner T can pass when moving from the inside of the toner box 61 toward the photosensitive layer 32 along the y-axis direction in the drawing.

<<< Schematic Configuration of Toner Carrier >>>
A toner electric field transport body 62 as a developer electric field transport device of the present invention is accommodated in the toner box 61.

  Referring to FIG. 2, the toner electric field transport body 62 includes a transport wiring board 63. The transport wiring board 63 is disposed so as to face the latent image forming surface LS across the top plate 61a and the toner passage hole 61a1 in the toner box 61.

  The toner transport surface TTS as the developer transport surface of the present invention is formed in parallel with the main scanning direction (z-axis direction in the figure). The toner transport surface TTS is provided so as to face the latent image forming surface LS on the photosensitive drum 3. Further, the developing position DP as the closest position where the latent image forming surface LS and the toner transport surface TTS are closest is substantially coincident with the center of the toner passage hole 61a1 in the sub-scanning direction (x-axis direction in the drawing). It has become.

  The transport wiring board 63 has the same configuration as the flexible printed wiring board.

  That is, the plurality of transport electrodes 63a are supported on the surface (transport electrode support surface 63b1) of the transport electrode support film 63b as the electrode support member of the present invention. The transport electrode 63a is made of a copper foil having a thickness of about several tens of μm. The transport electrode support film 63b is a flexible film and is made of an insulating synthetic resin such as a polyimide resin.

  The transport electrode 63a is formed as a linear wiring pattern having a longitudinal direction parallel to the main scanning direction (perpendicular to the sub-scanning direction). The plurality of transport electrodes 63a are arranged in parallel to each other. These transport electrodes 63a are arranged along the sub-scanning direction.

  Each of the plurality of transport electrodes 63a arranged in the sub-scanning direction is connected to the same power supply circuit every third.

  That is, the transfer electrode 63a connected to the power supply circuit VA, the transfer electrode 63a connected to the power supply circuit VB, the transfer electrode 63a connected to the power supply circuit VC, the transfer electrode 63a connected to the power supply circuit VD, and the power supply circuit VA. The connected transport electrodes 63a, the transport electrodes 63a connected to the power supply circuit VB, the transport electrodes 63a connected to the power supply circuit VC are arranged in order along the sub-scanning direction.

  Here, each power supply circuit VA thru | or VD is comprised so that the alternating voltage (carrier voltage) of a substantially identical waveform can be output. Further, the power supply circuits VA to VD are configured so that the phases of the waveforms of the voltages generated by the power supply circuits VA to VD are different by 90 °. That is, the voltage phase is delayed by 90 ° in order from the power supply circuit VA to the power supply circuit VD.

  The transport electrode coating layer 63c as the electrode covering member of the present invention is made of an insulating synthetic resin. The transport electrode coating layer 63c is provided so as to cover the transport electrode support surface 63b1 and the transport electrode 63a in the transport electrode support film 63b.

  The toner transport surface TTS described above is composed of the surface of the transport electrode coating layer 63c substantially parallel to the transport electrode support surface 63b1, and is formed as a smooth surface with very few irregularities.

  Thus, in the present embodiment, the transport electrode 63a is arranged along the toner transport surface TTS. That is, the transport electrode 63a is disposed in the vicinity of the toner transport surface TTS.

  The toner electric field transport body 62 also includes a transport substrate support member 64. The transport board support member 64 is made of a synthetic resin plate and is provided to support the transport wiring board 63 from below.

  Here, the toner electric field transport body 62 of the present embodiment is configured such that the toner transport direction TTD is in the direction along the sub-scanning direction as the array direction of the transport electrodes 63a.

  That is, the toner electric field transport body 62 generates a traveling-wave electric field along the sub-scanning direction by applying the transport voltage as described above to each transport electrode 63a in the transport wiring board 63. The positively charged toner T can be transported in the toner transport direction TTD.

<<< Popular wiring board >>>
Referring to FIG. 2, a counter wiring board 65 is mounted on the inner surface of the top plate 61 a of the toner box 61. The counter wiring substrate 65 is disposed to face the toner transport surface TTS with a predetermined gap therebetween.

  The counter wiring board 65 has the same configuration as the above-described transport wiring board 63.

  That is, the plurality of counter electrodes 65a are supported on the surface of the counter electrode support film 65b (counter electrode support surface 65b1). The counter electrode 65a is made of a copper foil having a thickness of about several tens of μm. The counter electrode support film 65b is a flexible film and is made of an insulating synthetic resin such as a polyimide resin.

  The counter electrode 65a is formed as a linear wiring pattern having a longitudinal direction parallel to the main scanning direction (perpendicular to the sub-scanning direction). The plurality of counter electrodes 65a are arranged in parallel to each other. These counter electrodes 65a are arranged along the sub-scanning direction.

  A large number of the counter electrodes 65a arranged along the sub-scanning direction are connected to the same power supply circuit every third.

  The counter electrode coating layer 65c is made of an insulating synthetic resin. The counter electrode coating layer 65c is provided so as to cover the counter electrode support surface 65b1 and the counter electrode 65a in the counter electrode support film 65b.

  The counter wiring substrate surface CS is composed of the surface of the counter electrode coating layer 65c substantially parallel to the counter electrode support surface 65b1, and is formed as a smooth surface with very few irregularities.

  Thus, in the present embodiment, the counter electrode 65a is disposed along the counter wiring substrate surface CS. That is, the counter electrode 65a is disposed in the vicinity of the counter wiring substrate surface CS.

  Similarly to the above-described transport wiring substrate 63, the counter wiring substrate 65 is applied with a predetermined voltage to the plurality of counter electrodes 65a, and generates a traveling wave electric field along the sub-scanning direction. The charged toner T can be transported in the toner transport direction TTD.

<< Detailed Configuration of Transport Wiring Board of Embodiment >>
FIG. 3 is an enlarged plan view of a part of the transport wiring board 63 shown in FIG. Hereinafter, the detailed configuration of the transport wiring board 63 in the present embodiment will be described with reference to FIGS. 2 and 3.

  Referring to FIG. 3, the transport wiring board 63 includes a first portion 631 and a second portion 632. A plurality of first portions 631 and second portions 632 are provided.

  2 and 3, the structure between the transport electrode support surface 63b1 and the toner transport surface TTS in the first portion 631 (thickness and / or material of the transport electrode 63a, the transport electrode coating layer 63c, etc.). The first portion 631 and the second portion 632 are configured to be different from the structure of the second portion 632.

  In the present embodiment, the first portion 631 and the second portion 632 are formed in a stripe shape (band shape) having a longitudinal direction parallel to the sub-scanning direction (x direction in the drawing) in plan view. Yes.

  As shown in FIG. 3, the first portion 631 and the second portion 632 are provided so as to be aligned along the longitudinal direction of the transport electrode 63a. The transport wiring board 63 is configured such that the first portions 631 and the second portions 632 are alternately positioned.

<Operation of laser printer>
Next, the operation of the laser printer 1 configured as described above will be described with reference to the drawings as appropriate.

<< Paper feeding action >>
First, referring to FIG. 1, the leading edge of the paper P stacked on a paper feed tray (not shown) is sent to the registration roller 21. The registration roller 21 corrects the skew of the paper P and adjusts the conveyance timing. Thereafter, the paper P is fed to the transfer position TP.

<< Carrying of toner image on latent image forming surface >>
As described above, while the sheet P is being conveyed toward the transfer position TP, an image of the toner T is carried on the latent image forming surface LS that is the peripheral surface of the photosensitive drum 3 as follows. .

<<< Formation of electrostatic latent image >>>
First, the latent image forming surface LS of the photosensitive drum 3 is uniformly charged positively by the charger 4.

  The latent image forming surface LS charged by the charger 4 is a scan which is a position facing (directly facing) the scanner unit 5 by the rotation of the photosensitive drum 3 in the direction (clockwise) indicated by the arrow in the drawing. It moves along the sub-scanning direction to the position SP.

  Referring to FIG. 2, a laser beam LB modulated based on image information is irradiated on the latent image forming surface LS at the scan position SP while being scanned along the main scanning direction. Depending on the modulation state of the laser beam LB, a portion where the positive charges on the latent image forming surface LS disappear is generated. Thereby, an electrostatic latent image LI having a positive charge pattern (image-like distribution) is formed on the latent image forming surface LS.

  The electrostatic latent image LI formed on the latent image forming surface LS moves toward a position facing the toner supply device 6 by rotating the photosensitive drum 3 in a direction (clockwise) indicated by an arrow in the drawing. To do.

<<< Conveyance and supply of charged toner >>>
Referring to FIG. 2, a voltage is applied in a traveling wave shape to the plurality of transport electrodes 63 a in the toner electric field transport body 62. As a result, a predetermined traveling-wave electric field is formed on the toner transport surface TTS. By this traveling wave electric field, the positively charged toner T is transported along the toner transport direction TTD on the toner transport surface TTS.

  FIG. 4 is a graph showing waveforms of voltages generated by the power supply circuits VA to VD shown in FIG. FIG. 5 is an enlarged side sectional view showing the periphery of the toner transport surface TTS shown in FIG. In FIG. 2, the transport electrode 63a connected to the power supply circuit VA is shown as the transport electrode 63aA in FIG. The same applies to the transport electrodes 63aB to 63aD.

  Hereinafter, how the positively charged toner T is transported in the toner transport direction TTD on the toner transport surface TTS will be described with reference to FIGS.

  As shown in FIG. 4, AC voltages having substantially the same waveform are output from the power supply circuits VA to VD so that the phase is delayed by 90 ° in order from the power supply circuit VA to the power supply circuit VD.

  At time t1 in FIG. 4, as shown in FIG. 5A, at the position between AB, which is the position between the transport electrode 63aA and the transport electrode 63aB, the direction opposite to the toner transport direction TTD ( An electric field EF1 in the direction opposite to x in FIG. 5 is formed.

  On the other hand, an electric field EF2 in the same direction as the toner transport direction TTD (the x direction in FIG. 5) is formed at the inter-CD position between the transport electrode 63aC and the transport electrode 63aD.

  Further, the position between BC, which is the position between the transport electrode 63aB and the transport electrode 63aC, and the position between DA, which is the position between the transport electrode 63aD and the transport electrode 63aA, are in the direction along the toner transport direction TTD. An electric field is not formed.

  That is, at time t1, the positively charged toner T receives an electrostatic force in the direction opposite to the toner transport direction TTD at the position between AB.

  Further, at the position between BC and the position between DA, the positively charged toner T receives almost no electrostatic force in the direction along the toner transport direction TTD.

  Further, at the position between the CDs, the positively charged toner T receives an electrostatic force in the same direction as the toner transport direction TTD.

  Therefore, at time t1, the positively charged toner T is collected at the position between the DAs. Similarly, at time t2, the positively charged toner T is collected at the position between AB. Next, at time t3, the positively charged toner T is collected at the position between BC.

  That is, the area where the toner T is collected moves on the toner transport surface TTS along the toner transport direction TTD with the passage of time.

  In this way, a voltage as shown in FIG. 4 is applied to each transport electrode 63a, whereby a traveling-wave electric field is formed on the toner transport surface TTS. As a result, the positively charged toner T is transported along the toner transport direction TTD while hopping in the y direction in the figure.

  Referring to FIG. 2, the toner T transporting operation by the counter wiring substrate 65 is the same as the toner T transporting operation by the transport wiring substrate 63 as described above.

<<< Development of electrostatic latent image >>>
Referring to FIG. 2, as described above, the positively charged toner T is transported in the toner transport direction TTD on the toner transport surface TTS. Thus, the toner T is supplied to the development position DP.

  In the vicinity of the development position DP, the electrostatic latent image LI formed on the latent image forming surface LS is developed by the toner T. That is, the toner T adheres to the portion on the latent image forming surface LS where the positive charge in the electrostatic latent image LI has disappeared. As a result, an image of the toner T (hereinafter referred to as “toner image”) is carried on the latent image forming surface LS.

<< Transfer of toner image from latent image forming surface to paper >>
Referring to FIG. 1, the toner image carried on the latent image forming surface LS of the photosensitive drum 3 as described above has a latent image forming surface LS in the direction (clockwise) indicated by the arrow in the drawing. Is conveyed toward the transfer position TP. At the transfer position TP, the toner image is transferred onto the paper P from the latent image forming surface LS.

<Operation / Effects of Configuration of Embodiment>
In the configuration of the present embodiment, the first portion 631 and the second portion 632 arranged along the longitudinal direction (z direction: the lateral direction in FIG. 3) of the transport electrode 63a, the transport electrode support surface 63b1 and The structure with the toner transport surface TTS is different. Then, the state (intensity and / or direction) of the electric field may be different between the first portion 631 and the second portion 632 on the toner transport surface TTS.

  As a result, in the vicinity of the boundary between the first portion 631 and the second portion 632, the longitudinal direction (z direction: lateral direction in FIG. 3) is applied to the traveling wave-like electric field generated on the toner transport surface TTS. A component along the line can occur. That is, a component along the main scanning direction can be generated in the above-described traveling-wave electric field generated on the toner transport surface TTS.

  Therefore, the charged toner T can also move in the direction along the longitudinal direction (the main scanning direction) on the toner transport surface TTS. That is, the charged toner T can move in the x direction in the figure while meandering, as indicated by a two-dot chain line in FIG.

  Here, for example, the aggregation of the toner T may occur in the toner box 61. Due to the aggregation of the toner T and the like, the “variation” along the sheet width direction in the initial conveyance amount of the toner (the supply amount of the toner T to the most upstream portion in the toner conveyance direction TTD of the toner conveyance surface TTS). Can occur.

  However, according to the configuration of the present embodiment, the toner T can meander as described above. Thereby, the variation in the transport amount generated along the paper width direction at the most upstream part can be effectively eliminated. That is, the variation along the paper width direction (the main scanning direction) of the transport amount of the toner T due to the traveling wave electric field on the toner transport surface TTS can be effectively suppressed.

  Accordingly, the positively charged toner T can be supplied to the development position DP in a state where unevenness in the supply amount in the main scanning direction is suppressed as much as possible. Therefore, density unevenness in the sheet width direction (the main scanning direction) of the toner image formed on the latent image forming surface LS can be suppressed as much as possible.

<Example of configuration of transport wiring board>
Next, a more specific configuration (example) of the transport wiring board 63 of the above-described embodiment will be described with reference to the drawings.

  FIG. 6 is a cross-sectional view showing the configuration of the first embodiment of the first portion 631 and the second portion 632 shown in FIG. That is, FIG. 6 is a cross-sectional view in which the AA cross section in FIG. 3 is partially enlarged.

  As shown in FIG. 6, the first portion 631 in this embodiment includes a first transport electrode coating layer 631c. The first transport electrode coating layer 631c has a first toner transport surface TTS1.

  In addition, the second portion 632 in this embodiment includes a second transport electrode coating layer 632c. The second transport electrode coating layer 632c has a second toner transport surface TTS2.

  The first transport electrode coating layer 631c is made of a material having a relative dielectric constant different from that of the second transport electrode coating layer 632c (note that the first transport electrode coating layer 631c and the second transport electrode coating layer 632c). And are formed to the same thickness.)

  That is, in the first portion 631, the structure between the first toner transport surface TTS1 and the transport electrode support surface 63b1 includes a transport electrode 63a made of a metal film having a constant thickness and a dielectric film having a constant thickness. And a first transport electrode coating layer 631c made of

  On the other hand, in the second portion 632, the structure between the second toner transport surface TTS2 and the transport electrode support surface 63b1 includes a transport electrode 63a made of a metal film having a constant thickness and a dielectric film having a constant thickness. The second transport electrode coating layer 632c having a relative dielectric constant different from that of the first transport electrode coating layer 631c is laminated.

  The operations and effects of the configuration of the first embodiment are the same as the operations and effects of the configuration of the second embodiment described below. Therefore, in the following, the configuration of the second embodiment and its operation and effect will be described in detail.

  FIG. 7 is a cross-sectional view showing the configuration of the second embodiment of the first portion 631 and the second portion 632 shown in FIG.

  As shown in FIG. 7, also in the present embodiment, the first portion 631 includes the first transport electrode coating layer 631 c and the second portion 632 as in the first embodiment described above. Includes a second transport electrode coating layer 632c. The first transport electrode coating layer 631c is made of a material having a relative dielectric constant different from that of the second transport electrode coating layer 632c.

  Further, in this embodiment, an intermediate layer 63d is provided between the transport electrode 63a and the first transport electrode coating layer 631c and the second transport electrode coating layer 632c. In the present embodiment, the intermediate layer 63d is formed with a substantially constant thickness.

  That is, in the first portion 631, the structure between the first toner transport surface TTS1 and the transport electrode support surface 63b1 includes a transport electrode 63a made of a metal film having a constant thickness and an intermediate layer 63d having a constant thickness. And a first transport electrode coating layer 631c made of a dielectric film having a constant thickness.

  On the other hand, the structure between the second toner transport surface TTS2 and the transport electrode support surface 63b1 in the second portion 632 is composed of a transport electrode 63a made of a metal film having a constant thickness and an intermediate layer 63d having a constant thickness. And a second transport electrode coating layer 632c having a specific dielectric constant different from that of the first transport electrode coating layer 631c.

  The results of the simulation of the configuration of Example 2 by the finite element method are shown in FIGS. In the simulations of FIGS. 8 and 9, the potential of the transport electrode 63a is set to + 150V or −150V, the relative dielectric constant of the first transport electrode coating layer 631c and the intermediate layer 63d is 3, and the ratio of the second transport electrode coating layer 632c. The dielectric constant was 400.

  FIG. 8 is a potential distribution diagram on the xy plane in FIG. 3 (shown in darker color as the potential is lower).

  FIG. 9 is a diagram showing a potential distribution (same as above) and an electric field state (the direction of the electric field is indicated by an arrow and the magnitude of the electric field is indicated by the length of the arrow) on the yz plane in FIG. is there. FIG. 9 shows the potential distribution and the electric field state of the cross section parallel to the yz plane at the approximate center in the x direction of the second transport electrode 63a from the left in FIG.

  As shown in FIG. 9, in the configuration of this embodiment, the first transport electrode coating layer 631 c and the second transport electrode coating layer 631 c and the second transport electrode coating layers 631 c arranged in the paper width direction (z-axis direction) and having different relative dielectric constants are arranged. An electric field having a component in the paper width direction (z-axis direction) is formed in the vicinity of the boundary with the transport electrode coating layer 632c.

  Accordingly, as described above, the toner T (see FIG. 2) can meander on the first toner transport surface TTS1 and the second toner transport surface TTS2.

  FIG. 10 is a cross-sectional view showing the configuration of the third embodiment of the first portion 631 and the second portion 632 shown in FIG.

  As shown in FIG. 10, the first portion 631 in the present embodiment includes a first intermediate layer 631d. Further, the second portion 632 in the present embodiment includes a second intermediate layer 632d.

  The first intermediate layer 631d is made of a material having a relative dielectric constant different from that of the second intermediate layer 632d (note that the first intermediate layer 631d and the second intermediate layer 632d have the same thickness). Formed).

  That is, the structure between the toner transport surface TTS and the transport electrode support surface 63b1 in the first portion 631 is composed of a transport electrode 63a made of a metal film having a constant thickness and a dielectric layer having a constant thickness. In this structure, a first intermediate layer 631d and a transport electrode coating layer 63c made of a dielectric film having a constant thickness are stacked.

  On the other hand, the structure between the toner transport surface TTS and the transport electrode support surface 63b1 in the second portion 632 is a transport electrode 63a made of a metal film having a constant thickness and a dielectric layer having a constant thickness. Thus, the second intermediate layer 632d having a relative dielectric constant different from that of the first intermediate layer 631d and a transport electrode coating layer 63c made of a dielectric film having a constant thickness are stacked.

  Also with this configuration, an electric field having a component in the paper width direction (z-axis direction) is formed in the vicinity of the boundary between the first portion 631 and the second portion 632 as in the above-described embodiments. The

  FIG. 11 is a cross-sectional view showing the configuration of the fourth embodiment of the first portion 631 and the second portion 632 shown in FIG.

  As shown in FIG. 11, the first portion 631 in this embodiment includes a first transport electrode coating layer 631c and a first intermediate layer 631d. In addition, the second portion 632 in this embodiment includes a second transport electrode coating layer 632c and a second intermediate layer 632d.

  In this embodiment, the first transport electrode coating layer 631c and the second transport electrode coating layer 632c are integrally formed of the same material. That is, the first transport electrode coating layer 631c and the second transport electrode coating layer 632c are made of a material having the same relative dielectric constant.

  Similarly, the first intermediate layer 631d and the second intermediate layer 632d in the present embodiment are integrally formed of the same material. That is, the first intermediate layer 631d and the second intermediate layer 632d are made of a material having the same relative dielectric constant. The first intermediate layer 631d and the second intermediate layer 632d are made of a material having a relative dielectric constant different from that of the first transport electrode coating layer 631c and the second transport electrode coating layer 632c.

  The first intermediate layer 631d in the present embodiment is formed thicker than the second intermediate layer 632d. On the other hand, the first transport electrode coating layer 631c in the present embodiment is formed thinner than the second transport electrode coating layer 632c.

  Then, the first transport electrode coating layer 631c and the first intermediate layer 631d have a total thickness equal to the total thickness of the second transport electrode coating layer 632c and the second intermediate layer 632d. The portion 631 and the second portion 632 are configured.

  That is, in the first portion 631, the structure between the toner transport surface TTS and the transport electrode support surface 63b1 is composed of a transport electrode 63a made of a metal film having a constant thickness and a first intermediate layer 631d made of a dielectric layer. And a first transport electrode coating layer 631c made of a dielectric film having a relative dielectric constant different from that of the first intermediate layer 631d.

  On the other hand, the structure between the toner transport surface TTS and the transport electrode support surface 63b1 in the second portion 632 is made of the same material as the transport electrode 63a made of a metal film having a certain thickness and the first intermediate layer 631d. A second intermediate layer 631d made of a dielectric layer having a different thickness, and a dielectric film having a different dielectric constant from the second intermediate layer 631d and having the same material as the first transport electrode coating layer 631c and a different thickness And a second transport electrode coating layer 632c made of

  Also with this configuration, an electric field having a component in the paper width direction (z-axis direction) is formed in the vicinity of the boundary between the first portion 631 and the second portion 632 as in the above-described embodiments. The

  FIG. 12 is a cross-sectional view showing the configuration of the fifth embodiment of the first portion 631 and the second portion 632 shown in FIG.

  As shown in FIG. 12, the first portion 631 in this embodiment includes a first transport electrode coating layer 631c, an intermediate layer 63d, and an auxiliary intermediate layer 631e. Further, the second portion 632 in this embodiment includes a second transport electrode coating layer 632c and an intermediate layer 63d.

  In this embodiment, the first transport electrode coating layer 631c and the second transport electrode coating layer 632c are integrally formed of the same material. That is, the first transport electrode coating layer 631c and the second transport electrode coating layer 632c are made of a material having the same relative dielectric constant. On the other hand, the first transport electrode coating layer 631c in the present embodiment is formed thinner than the second transport electrode coating layer 632c.

  Further, the first portion 631 and the second portion 632 are configured such that the total thickness of the first transport electrode coating layer 631c and the auxiliary intermediate layer 631e is equal to the thickness of the second transport electrode coating layer 632c. Has been.

  The auxiliary intermediate layer 631e is made of a material having a relative dielectric constant different from that of the first transport electrode coating layer 631c, the second transport electrode coating layer 632c, and the intermediate layer 63d.

  Also with this configuration, an electric field having a component in the paper width direction (z-axis direction) is formed in the vicinity of the boundary between the first portion 631 and the second portion 632 as in the above-described embodiments. The

  FIG. 13 is a cross-sectional view showing the configuration of the sixth embodiment of the first portion 631 and the second portion 632 shown in FIG.

  As shown in FIG. 13, a protrusion 63a1 is formed at a position corresponding to the first portion 631 of the transport electrode 63a. That is, in the present embodiment, the first portion 631 and the second portion 632 are configured so that the thickness of the transport electrode 63a differs between the first portion 631 and the second portion 632.

  There is no limitation in particular in the shape of this projection part 63a1. For example, the protrusion 63a1 may be formed as a layered protrusion having the same thickness as the main body of the transport electrode 63a (a thin portion other than the protrusion 63a1). Alternatively, the protrusion 63a1 may be made of conductive fine particles.

  Such a transport electrode 63a provided with the protrusion 63a1 can be easily formed by, for example, applying a metal paste by a screen printing method.

  Also with this configuration, an electric field having a component in the paper width direction (z-axis direction) is formed in the vicinity of the boundary between the first portion 631 and the second portion 632 as in the above-described embodiments. The

<List of examples of modification>
The above-described embodiments and examples are merely examples of typical embodiments and examples of the present invention that the applicant has considered to be the best at the time of filing the application as described above. . Therefore, the present invention is not limited to the above-described embodiments and examples. Therefore, it goes without saying that various modifications can be made to the above-described embodiments and examples without departing from the essential part of the present invention.

  Hereinafter, some typical modifications will be exemplified. In the following description of the modified examples, the same reference numerals as those in the above-described embodiments and examples are used for members having the same configurations and functions as those described in the above-described embodiments and examples. To get. And about description of this member, the description in the above-mentioned embodiment shall be used in the range which is not technically consistent.

  However, it goes without saying that the modifications are not limited to those listed below. In addition, a plurality of modified examples can be applied in a composite manner as appropriate within a technically consistent range.

  The present invention (especially those expressed in terms of action and function in each component constituting the means for solving the problems of the present invention) is based on the description of the above embodiment and the following modifications. It should not be interpreted in a limited way. Such a limited interpretation, while improperly harming the applicant's interests (rushing to file under an earlier application principle), improperly imitates the patent for the protection and use of the invention Contrary to the purpose of the law, it is not allowed.

  (1) The application target of the present invention is not limited to a monochromatic laser printer. For example, the present invention can be suitably applied to a so-called electrophotographic image forming apparatus such as a color laser printer or a monochromatic and color copying machine. At this time, the shape of the photosensitive member may not be a drum shape as in the above-described embodiment. For example, a flat plate shape or an endless belt shape may be used.

  Alternatively, the present invention is also suitably applied to an image forming apparatus of a system other than the above-described electrophotographic system (for example, a toner jet system that does not use a photoreceptor, an ion flow system, a multi-stylus electrode system, etc.). obtain.

  (2) In the above-described embodiment, the waveform of the voltage generated by each of the power supply circuits VA to VD is a rectangular waveform, but may be a waveform of another shape such as a sine waveform or a triangular waveform. .

  In the above embodiment, the four power supply circuits VA to VD are provided and the phases of the voltages generated by the power supply circuits VA to VD are different from each other by 90 °. The phase of the voltage generated by the power supply circuit may be different by 120 °.

  (3) The above-described embodiments can be combined with each other. Alternatively, it can be changed appropriately.

  That is, for example, the intermediate layer 63d, the first intermediate layer 631d, and the second intermediate layer 632d in FIGS. 11 to 13 can be omitted.

  Alternatively, instead of the transport electrode coating layer 63c in FIG. 10, the first transport electrode coating layer 631c and the second transport electrode coating layer 632c in FIG. 9 may be applied.

  Alternatively, the relative permittivity of the first transport electrode coating layer 631c and the relative permittivity of the second transport electrode coating layer 632c in FIGS. 11 and 12 may be different.

  Alternatively, the relative dielectric constant of the first intermediate layer 631d and the relative dielectric constant of the second intermediate layer 632d in FIGS. 11 and 12 may be different.

  Alternatively, instead of the transport electrode 63a in FIGS. 6, 7, 11, and 12, the transport electrode 63a in FIG. 13 can be applied.

  (4) As shown in FIG. 3, the transport wiring board 63 has a first portion 631 and a second portion 632 in a number of stripes along the sub-scanning direction in plan view ( It is not limited to the structure arranged in a strip shape.

  For example, the first portion 631 may be formed only at both ends in the paper width direction, and the second portion 632 may be formed between the pair of first portions 631. Or conversely, the second portion 632 may be formed only at both ends in the paper width direction, and the first portion 631 may be formed between the pair of second portions 632.

  14 to 19 are plan views showing configurations of modified examples of the transport wiring board 63 shown in FIG.

  For example, as shown in FIG. 14, the first portion 631 and the second portion 632 can be arranged in an oblique stripe shape that intersects the sub-scanning direction in plan view.

  Alternatively, as shown in FIG. 15 and FIG. 16, the first portion 631 and the second portion 632 have a polygonal shape (parallelogram shape) arranged so as to be adjacent to each other in plan view. Can be formed.

  Here, as illustrated in FIG. 15, the first portions 631 and the second portions 632 may be alternately arranged in a direction parallel to the longitudinal direction of the transport electrode 63a. Alternatively, as shown in FIG. 16, the first portions 631 and the second portions 632 may be alternately arranged in a direction intersecting with the longitudinal direction of the transport electrode 63a.

  Alternatively, as shown in FIG. 17, the first portion 631 may be provided so as to constitute a first stripe and a second stripe that intersect each other in plan view. In this case, the second portion 632 includes a portion surrounded by the first portion 631 in a plan view, that is, a portion surrounded between the first stripe and the second stripe described above. obtain.

  Alternatively, as shown in FIG. 18, the first portion 631 and the second portion 632 can be randomly arranged. In this case, the shapes of the first portion 631 and the second portion 632 in plan view can be formed in a plurality of types.

  Alternatively, three or more portions having different structures between the transport electrode support surface 63b1 and the toner transport surface TTS may be configured to be adjacent to each other.

  Specifically, for example, as shown in FIG. 19, the first portion 631, the second portion 632, and the third portion 633 are arranged so as to be adjacent to each other in plan view. It can be formed in a hexagonal shape.

  (5) The counter wiring board 65 may be configured in the same manner as the transport wiring board 63 of the above-described embodiment, each example, and each modification. Alternatively, the counter wiring substrate 65 can be omitted partially or entirely.

  (6) Other than that, various modifications other than these can be made without departing from the gist of the present invention.

  In addition, in each element constituting the means for solving the problems of the present invention, the elements expressed in terms of operation and function are the specific structures disclosed in the above-described embodiments and modifications, It includes any structure that can realize this action / function.

1 is a side view showing a schematic configuration of a laser printer according to an embodiment of the present invention. FIG. 2 is an enlarged side cross-sectional view of a portion where the photosensitive drum and the toner supply device shown in FIG. 1 face each other. FIG. 3 is an enlarged plan view of a part of the transport wiring board shown in FIG. 2. FIG. 3 is a graph showing a waveform of a voltage generated by each power supply circuit shown in FIG. 2. FIG. FIG. 3 is a side cross-sectional view showing an enlarged periphery of a toner conveyance surface shown in FIG. 2. FIG. 4 is a cross-sectional view (a cross-sectional view in which the AA cross section in FIG. 3 is partially enlarged) showing the configuration of the first embodiment and the second portion of the first embodiment shown in FIG. 3. It is sectional drawing which shows the structure of the 2nd Example of the 1st part and 2nd part which are shown by FIG. FIG. 4 is a potential distribution diagram on an xy plane in FIG. 3. It is a figure which shows the electric potential distribution in the yz plane in FIG. 3, and the state of an electric field. It is sectional drawing which shows the structure of the 3rd Example of the 1st part and 2nd part which are shown by FIG. It is sectional drawing which shows the structure of the 4th Example of the 1st part and 2nd part which are shown by FIG. It is sectional drawing which shows the structure of the 5th Example of the 1st part and 2nd part which are shown by FIG. It is sectional drawing which shows the structure of the 6th Example of the 1st part shown by FIG. 3, and a 2nd part. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG. It is a top view which shows the structure of the modification of the conveyance wiring board shown by FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laser printer 3 ... Photosensitive drum (electrostatic latent image carrier / developer carrier)
6. Toner supply device (developer supply device)
DESCRIPTION OF SYMBOLS 31 ... Drum main body 32 ... Photosensitive layer 61 ... Toner box 61a ... Top plate 62 ... Toner conveyance body (developer electric field conveyance apparatus)
63 ... Transport wiring board 63a ... Transport electrode 63a1 ... Projection 63b ... Transport electrode support film (electrode support member)
63b1 ... transport electrode support surface 63c ... transport electrode coating layer (electrode covering member)
63d ... Intermediate layer 631 ... first portion 631c ... first transport electrode coating layer 631d ... first intermediate layer 631e ... auxiliary intermediate layer 632 ... second portion 632c ... second transport electrode coating layer 632d ... second intermediate layer 633 ... Third part CS ... Opposite wiring board surface DP ... Development position (closest position)
LB ... Laser beam LI ... Electrostatic latent image LS ... Latent image forming surface (developer carrying surface)
P ... paper T ... toner TTD ... toner transport direction TTS ... toner transport surface (developer transport surface)
TTS1... First toner transport surface TTS2... Second toner transport surface

Claims (33)

A latent image forming surface that is formed in parallel with a predetermined main scanning direction and configured to form an electrostatic latent image by a potential distribution; and the latent image forming surface is a sub-surface orthogonal to the main scanning direction. An electrostatic latent image carrier configured to be movable along a scanning direction;
A developer supply device arranged to face the electrostatic latent image carrier and configured to supply the developer to the latent image forming surface in a charged state;
An image forming apparatus comprising:
The developer supply device includes:
The developer is arranged along the sub-scanning direction, has a longitudinal direction that intersects the sub-scanning direction, and transports the developer in a predetermined developer transport direction by applying a traveling wave voltage. A plurality of transport electrodes configured to obtain;
An electrode support member configured to support the transport electrode on a surface thereof;
An electrode covering member that is formed so as to cover the surface of the electrode support member and the transport electrode, and includes a developer transport surface that is parallel to the main scanning direction and faces the latent image forming surface;
With
The image forming apparatus, wherein the electrode covering member is formed such that a first portion and a second portion having different relative dielectric constants are arranged along the longitudinal direction of the transport electrode. The image forming apparatus according to claim 1 ,
The image forming apparatus, wherein the electrode covering member is formed to have a different thickness between the first portion and the second portion. The image forming apparatus according to claim 1, wherein:
An intermediate layer formed between the electrode covering member and the transport electrode;
2. The image forming apparatus according to claim 1, wherein the intermediate layer is formed so that the relative permittivity is different between the first portion and the second portion. The image forming apparatus according to claim 2 .
An intermediate layer formed between the thinner portion of the electrode covering member and the transport electrode;
The image forming apparatus, wherein the intermediate layer has a relative dielectric constant different from that of the electrode covering member. The image forming apparatus according to any one of claims 1 to 4 , wherein:
The image forming apparatus, wherein the first portion and the second portion are arranged in stripes along the sub-scanning direction in a plan view. The image forming apparatus according to any one of claims 1 to 4 , wherein:
The image forming apparatus, wherein the first part and the second part are formed in a polygonal shape so as to be adjacent to each other in plan view. The image forming apparatus according to any one of claims 1 to 4 , wherein:
The image forming apparatus, wherein the first portion and the second portion are arranged in an oblique stripe shape intersecting the sub-scanning direction in a plan view. The image forming apparatus according to any one of claims 1 to 4 , wherein:
Either one of the first part or the second part is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view,
The other of the first portion or the second portion, which is different from the one, is configured by a portion surrounded by the first stripe and the second stripe in a plan view. An image forming apparatus as a feature. The image forming apparatus according to any one of claims 1 to 8 ,
The image forming apparatus, wherein the first part and the second part are randomly arranged. The image forming apparatus according to claim 1 , wherein:
The image forming apparatus, wherein the transport electrode is formed so that the first portion and the second portion have different thicknesses. An image forming apparatus according to any one of claims 1 to 10 ,
An image forming apparatus, wherein a protrusion is formed at a position corresponding to the first portion of the transport electrode. A developer carrying surface that is parallel to a predetermined main scanning direction and has a developer carrying surface on which the developer can be carried, and the developer carrying surface can move along a sub-scanning direction orthogonal to the main scanning direction. In a developer supply device configured to be able to be supplied along a predetermined developer transport direction in a state where the developer is charged to a body,
The developer is arranged along the sub-scanning direction, has a longitudinal direction that intersects the sub-scanning direction, and transports the developer in a predetermined developer transport direction by applying a traveling wave voltage. A plurality of transport electrodes configured to obtain;
An electrode support member configured to support the transport electrode on a surface thereof;
An electrode covering member that is formed so as to cover the surface of the electrode support member and the transport electrode, and includes a developer transport surface that is parallel to the main scanning direction and faces the developer carrying surface;
With
The developer supply apparatus, wherein the electrode covering member is formed such that a first portion and a second portion having different relative dielectric constants are arranged along the longitudinal direction of the transport electrode. . The developer supply device according to claim 12 , wherein
The developer supplying apparatus, wherein the electrode covering member is formed so that the first portion and the second portion have different thicknesses. The developer supply device according to claim 12 or 13 ,
An intermediate layer formed between the electrode covering member and the transport electrode;
The developer supply apparatus according to claim 1, wherein the intermediate layer is formed so that the relative dielectric constants of the first portion and the second portion are different. The developer supply device according to claim 13 ,
An intermediate layer formed between the thinner portion of the electrode covering member and the transport electrode;
The developer supply apparatus according to claim 1, wherein the intermediate layer has a relative dielectric constant different from that of the electrode covering member. The developer supply device according to any one of claims 12 to 15 ,
The developer supply apparatus, wherein the first portion and the second portion are arranged in a stripe shape along the sub-scanning direction in a plan view. The developer supply device according to any one of claims 12 to 15 ,
The developer supply apparatus, wherein the first part and the second part are formed in a polygonal shape so as to be adjacent to each other in plan view. The developer supply device according to any one of claims 12 to 15 ,
The developer supply apparatus, wherein the first portion and the second portion are arranged in an oblique stripe shape intersecting the sub-scanning direction in a plan view. The developer supply device according to any one of claims 12 to 15 ,
Either one of the first part or the second part is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view,
The other of the first portion or the second portion, which is different from the one, is configured by a portion surrounded by the first stripe and the second stripe in a plan view. A developer supply device characterized by the above. The developer supply device according to any one of claims 12 to 19 ,
The developer supply apparatus, wherein the first part and the second part are randomly arranged. The developer supply device according to any one of claims 12 to 20 ,
The developer supply apparatus according to claim 1, wherein the transport electrode is formed so that the first portion and the second portion have different thicknesses. The developer supply device according to any one of claims 12 to 21 ,
A developer supply apparatus, wherein a protrusion is formed at a position corresponding to the first portion of the transport electrode. In the developer electric field transport device configured to transport the charged developer along a predetermined developer transport direction by an electric field.
The surface of the developer carrying member disposed to face the developer electric field transport device and arranged along the sub-scanning direction, which is the moving direction of the developer carrying surface as the surface on which the developer is carried. A plurality of transport electrodes having a longitudinal direction intersecting the sub-scanning direction and configured to transport the developer in the developer transport direction when a traveling wave voltage is applied. When,
An electrode support member configured to support the transport electrode on a surface thereof;
An electrode covering member provided with a developer transport surface that is formed so as to cover the surface of the electrode support member and the transport electrode, and that faces the developer carrying surface in parallel with the main scanning direction orthogonal to the sub-scanning direction. When,
With
The electrode covering member is formed such that a first portion and a second portion having different relative dielectric constants are arranged along the longitudinal direction of the transport electrode. apparatus. The developer electric field conveying device according to claim 23 ,
The developer electric field transport device, wherein the electrode covering member is formed to have a different thickness between the first portion and the second portion. In the developer electric field transport device according to claim 23 or 24 ,
An intermediate layer formed between the electrode covering member and the transport electrode;
The developer electric field transport device according to claim 1, wherein the intermediate layer is formed such that the relative permittivity of the first portion is different from that of the second portion. The developer electric field transport device according to claim 24 ,
An intermediate layer formed between the thinner portion of the electrode covering member and the transport electrode;
The developer electric field transport device, wherein the intermediate layer has a dielectric constant different from that of the electrode covering member. The developer electric field transport device according to any one of claims 23 to 26 ,
The developer electric field transport device, wherein the first portion and the second portion are arranged in a stripe shape along the sub-scanning direction in a plan view. The developer electric field transport device according to any one of claims 23 to 26 ,
The developer electric field transport device, wherein the first portion and the second portion are formed in a polygonal shape so as to be adjacent to each other in plan view. The developer electric field transport device according to any one of claims 23 to 26 ,
The developer electric field transport device, wherein the first portion and the second portion are arranged in an oblique stripe shape intersecting the sub-scanning direction in a plan view. The developer electric field transport device according to any one of claims 23 to 26 ,
Either one of the first part or the second part is provided so as to constitute a first stripe and a second stripe that intersect each other in plan view,
The other of the first portion or the second portion, which is different from the one, is configured by a portion surrounded by the first stripe and the second stripe in a plan view. A developer electric field conveying device. The developer electric field transport device according to any one of claims 23 to 30 ,
The developer electric field transport device, wherein the first part and the second part are randomly arranged. A developer electric field transport device according to any one of claims 23 to 31 ,
The developer electric field transport device according to claim 1, wherein the transport electrodes are formed to have different thicknesses between the first portion and the second portion. A developer electric field transport device according to any one of claims 23 to 32 ,
A developer electric field transport apparatus, wherein a protrusion is formed at a position corresponding to the first portion of the transport electrode.