WO2001032432A1

WO2001032432A1 - Image forming device

Info

Publication number: WO2001032432A1
Application number: PCT/JP2000/007773
Authority: WO
Inventors: Taichi Itoh; Akira Kumon; Yoshitaka Kitaoka; Hidenori Tomachi; Masahiro Aizawa
Original assignee: Matsushita Electric Industrial Co., Ltd.; Array Ab
Priority date: 1999-11-04
Filing date: 2000-11-02
Publication date: 2001-05-10
Also published as: AU1056401A

Abstract

An image forming device, comprising a developer (5a) having a carrier roller (11) carrying and transporting a toner (8a) and a storage container (9) having the toner (8a) stored therein, both formed integrally with each other, a cabinet member (2a) having the developer (5a) installed detachably thereon, a control plate (4) installed at the tip of the cabinet member (2a) and having a plurality of toner passing holes (23) formed therein, an intermediate image belt (7) having passed developer (8a) adhering thereto, and roller-shaped back face electrodes (6a), wherein the intermediate image belt (7) is brought into contact with each back face electrode (6a) to provide a specified angle of contact Υ.

Description

Description Image forming equipment Technical field

The present invention relates to an image forming apparatus that forms an image by ejecting a developer to a recording member. Background art

In recent years, in offices, with the improvement of personal computer capabilities and the advancement of network technology, printers, facsimile machines, copiers, etc., with high processing capabilities capable of handling large volumes of documents, have become widespread. On the other hand, the frequency of use of color documents is also increasing due to the rapid spread of ink-jet printing. However, image forming apparatuses capable of outputting satisfactory black-and-white or color documents from the viewpoints of printing speed, image quality, and the like are still under development, and such apparatuses are expected to appear.

As one of the image forming apparatuses, a developer injection type apparatus is known. In this type of apparatus, first, an acceleration electric field is generated by inputting an image signal to a control electrode provided on a control plate of a print head, and the charged developer is used for the control plate by utilizing the acceleration electric field. Fly so that it passes through the specified developer passage hole. Then, the developer is sucked by the back electrode, so that the developer is attached to a recording medium moving between the control plate and the back electrode, and an image is formed on the recording medium. For example, Japanese Patent Publication No. 44-263333 discloses a device of a method of directly forming an image on a recording sheet by ejecting toner onto the recording sheet (direct marking method). I have. Further, Japanese Patent Application Laid-Open No. Hei 8-144239 discloses a plurality of developing devices arranged in the conveying direction of recording paper, each of which is composed of yellow, magenta, cyan, and black. A configuration comprising a plurality of back electrodes arranged two-dimensionally on a support table so as to face each developing device with the It is shown.

On the other hand, there is also known an apparatus for forming an image via an intermediate image pelt instead of forming an image directly on recording paper as in the above-described apparatus. In this type of apparatus, a developer is ejected from a print head onto an intermediate image pelt, an intermediate image is formed once on the intermediate image belt, and then the intermediate image on the belt is transferred to a recording paper using a transfer mechanism. To form an image on recording paper. As this type of apparatus, there is an apparatus in which an intermediate image belt and a back electrode are brought into contact with each other, as in an apparatus disclosed in US Pat. No. 5,559,586. Japanese Patent Application Laid-Open No. Hei 9-130683 discloses a configuration in which a plurality of developing devices of each color of yellow, magenta, and cyan are arranged along the traveling direction of a transfer belt. By the way, in the developer injection type apparatus, the distance between the control plate and the recording medium (hereinafter, referred to as a head distance) or the distance between the developer carrying roller and the control plate is very short. For this reason, there are various problems caused by the short head spacing and the like, such as high-precision positioning of the control board and the like and securing insulation.

For example, if the head spacing varies, the flight time of the developer becomes non-uniform, and the recording characteristics deteriorate significantly. Therefore, it is extremely important to keep the head spacing constant in a developer injection type device. In particular, in an apparatus that forms a color image using a plurality of color developers, the overall color balance may fluctuate significantly even if the recording characteristics of each color are slightly reduced. Therefore, stabilization of recording characteristics is strongly desired.

In an apparatus that directly sprays a developer onto a recording sheet, such as the apparatus disclosed in Japanese Patent Application Laid-Open No. 8-142,389, the head spacing is not sufficient because the quality (flatness, etc.) of the recording sheet is not stable. Tends to be stable. Therefore, there is a problem that the fluctuation of the recording characteristics is large. On the other hand, in an apparatus using an intermediate image belt, a belt having a higher quality than a recording sheet is used as a recording medium, so that the head interval is more stable than in the above-described apparatus. However, the apparatus disclosed in the above-mentioned U.S. Pat. No. 5,559,586 uses a single-color developer, so that a color image cannot be formed with the same configuration. . Although the apparatus disclosed in Japanese Patent Application Laid-Open No. 9-300683 is capable of forming a color image, The yellow, magenta, and cyan developing units are arranged in series in the same direction as the running direction of the intermediate image pelt, and the back electrodes corresponding to the developing units are arranged in parallel with the intermediate image belt. It was arranged in a straight line. Therefore, if the parallelism between a plurality of back electrodes is impaired due to, for example, one back electrode protruding toward the intermediate image belt from the other back electrodes, some back electrodes and the intermediate image belt may be damaged. There was a gap between the heads and the head spacing became unstable, and image quality was likely to deteriorate.

Further, in a developer injection type device, in order to form dots of, for example, about 100 μm on a recording sheet, a developer carrying roller and a control plate, or a control plate and a back electrode are connected. It is necessary to approach each other at minute intervals of about several hundred microns, and selectively apply a high voltage of several hundred to several thousand volts to the minute intervals.

In this regard, Japanese Patent Application Laid-Open Nos. Hei 9-30032 and Hei 9-39289 disclose that the control electrode is located on the back of the control plate so that the control electrode does not directly face the developer carrying roller. (A surface opposite to the surface facing the developer carrying roller) is disclosed. The control plate includes an insulating sheet and a control electrode. By adopting such a configuration, the insulating sheet is interposed between the control electrode and the developer carrying roller. Therefore, an electrical short circuit between the control electrode and the developer carrying roller is temporarily prevented.

However, in the configurations described in JP-A-9-30032 and JP-A-9-139289, the control electrode is provided on the surface of the insulating sheet facing the developer carrying roller. Since it is disposed on the back surface, the distance between the developer carrying roller and the control electrode becomes longer by the thickness of the insulating sheet. For this reason, it was difficult to secure the required electrolytic strength, and the flight of the developer was not stable. As a result, there is a problem that it is difficult to obtain a sufficient image quality. In recent years, a diaphragm electrode for controlling the flying of the developer is often provided separately from the control electrode for the purpose of preventing deflection and convergence of the flying direction of the developer. As described above, in order to provide the aperture electrode separately, the simplest configuration is to provide the control electrode on one surface of the control plate and provide the aperture electrode on the other surface. However, in the above configuration in which the electrodes are not directly opposed to the developer carrying roller, a simple configuration in which the electrodes are provided on both sides of the control plate is employed. I can't do that.

Since the developer passage hole in the control plate is a fine small hole of about 100 m, the developer passage hole is likely to be clogged by foreign substances (dust, dust, etc.) scattered in the device and the developer itself. . However, when such clogging occurs, the smooth passage of the developer is hindered, and there is a possibility that the dots become thinner or the dots do not come out. Therefore, a configuration is desired in which a developer carrying roller control plate is opened to the outside as necessary, and a cleaning operation for mechanically removing accumulated developer and foreign matter can be appropriately performed.

Further, since the developer is a consumable item, when the developer in the apparatus runs short, it is necessary to replace the developer supply unit and the like in order to supply the developer. However, during such replacement work, foreign matter such as a metal piece may enter the apparatus from the outside, and such foreign matter may adhere to the developing agent carrying roller or the vicinity of the control electrode of the control plate. If such foreign matter enters, the surfaces of the control plate and the developer carrying roller may be damaged, and the image quality may be locally reduced or so-called dot missing may occur. Further, if a foreign substance is caught between the control electrode and the developer carrying port, the control electrode and the developer carrying roller may be electrically short-circuited, and the reliability of the apparatus may be impaired.

In view of the above background, an object of the present invention is to solve various problems caused by a short head spacing and the like.

According to one aspect of the present invention, by stabilizing the head interval in all of the plurality of developing units, uniform recording conditions are achieved for the plurality of developing units, and high quality with excellent color balance is achieved. An object of the present invention is to provide an image forming apparatus which can form a blank image, is easy to use, and can be easily miniaturized.

According to another aspect of the present invention, it is possible to prevent foreign matter from entering or adhering to the developer carrying roller or the control plate from the outside at the time of replacing the developer supply unit or cleaning the print head. An object of the present invention is to provide a highly reliable image forming apparatus capable of forming a high-quality image by removing a foreign substance even when the foreign substance is attached. Disclosure of the invention

According to a first aspect of the present invention, there is provided a developer carrier that carries and transports a charged developer, a back electrode disposed so as to face the developer carrier, the developer carrier, and the back electrode. An intermediate image holding means disposed between the developer carrier and the intermediate image holding means, and an insulating base material having a plurality of developer passage holes formed therein; A signal electrode disposed around each of the developer passage holes in the conductive base material and to which an image signal is supplied. A developer passage control member that flies so as to pass through the developer passage hole and adheres to the intermediate image holding unit, and forms an intermediate image on the intermediate image holding unit; and an intermediate image on the intermediate image holding unit. Transfer means for transferring to a recording medium, wherein the back electrode is provided with the intermediate image It has a contact portion that is in contact with the holding means so as to have a winding angle of 2 to 90 degrees.

According to the first aspect, since the contact area between the intermediate image holding means and the back electrode is increased, the intermediate image holding means travels in a state in which it is securely in contact with the back electrode. Therefore, the interval between the developer passage control member and the intermediate image holding unit, that is, the head interval is stabilized. Therefore, a high level of image quality is formed.

In a second aspect based on the first aspect, the back electrode is formed by a columnar or cylindrical electrode extending in a direction orthogonal to a running direction of the intermediate image holding means.

According to the second aspect of the present invention, with a simple configuration, a back electrode that comes into contact with the intermediate image holding means so as to have a predetermined winding angle is realized.

In a third aspect based on the second aspect, the back electrode is constituted by a rotatable electrode roller.

According to the third aspect, the dynamic friction between the intermediate image holding means and the back electrode during traveling of the intermediate image holding means is reduced. Therefore, the intermediate image holding means runs smoothly despite the contact area between the intermediate image holding means and the back electrode having a wrapping angle to increase the mutual contact area. In addition, since the wear of the intermediate image holding means and the back electrode is small, the life and reliability of the apparatus are improved. According to a fourth aspect of the present invention, in the first aspect, a developer supply unit having a container for accommodating a developer and having the developer carrying member attached thereto, and the developer supply unit being freely insertable and removable. And a developer passage control member, wherein the developer passage control member is attached to the housing member.

According to the fourth aspect, the developer supply unit is easily attached and detached by the operation of inserting and removing the developer supply unit with respect to the housing member. Therefore, replacement of the developer supply unit and replenishment of the developer are easy. Further, simply by attaching the developer supply unit to the housing member, the alignment between the developer carrier and the developer passage control member (particularly, the developer passage hole) is automatically realized. Therefore, the positional relationship between the developer carrier and the developer passage control member is set to a predetermined positional relationship with high accuracy.

In a fifth aspect based on the fourth aspect, the developer supply unit is provided between the developer carrier and the back electrode when the developer supply unit is mounted on the housing member. And a first spacer in contact with the back electrode so as to keep a predetermined interval.

According to the fifth aspect of the invention, when the developer supply unit is mounted on the housing member, the first spacer is brought into contact with the back electrode, and the distance between the developer carrier and the back electrode is fixed. The interval will be set with high precision.

In a sixth aspect based on the fifth aspect, the developer passage control member comprises a control plate having one end fixed to the housing member and the other end connected to the housing member via a tension member. The developer carrier is in contact with the control plate so as to press the control plate.

According to the sixth aspect, when the developer supply unit is mounted on the housing member, the developer carrier is simply brought into contact with the control plate, and the distance between the developer carrier and the control plate is a predetermined distance. Is set to high accuracy. As a result, the interval between the control plate and the intermediate image holding means, that is, the head interval is set with high accuracy. Therefore, the recording conditions are made uniform, and the image quality is stabilized. In a seventh aspect based on the fifth aspect, the developer passage control member comprises a control plate having one end fixed to the housing member and the other end connected to the housing member via a tension member. The developer carrier is in contact with the control plate via a second spacer so as to press the control plate.

According to the seventh aspect, when the developer supply unit is mounted on the housing member, the developer carrier is simply brought into contact with the control plate via the second spacer, and the developer carrier and the developer carrier are connected to each other. The distance from the control plate is set to a predetermined distance with high accuracy. Therefore, the head interval is set with high accuracy, and the image quality is stabilized.

In an eighth aspect based on the fourth aspect, the developer supply unit is provided with first engagement means, and the housing member is engaged with the first engagement means, Second engaging means for guiding insertion and removal of the developer supply unit is provided. According to the eighth aspect, when the developer supply unit is mounted, the first engagement means and the second engagement means are engaged, so that the developer supply unit is guided to a predetermined position. Therefore, the developer carrier and the back electrode are easily and accurately aligned. In a ninth aspect based on the eighth aspect, the first engagement means comprises a projection or a rod-shaped member projecting from the developer supply unit, and the second engagement means comprises Is a guide means for guiding the rod-shaped member.

According to the ninth aspect, at the time of mounting the developer supply unit, the protrusion or the rod-shaped member of the developer supply unit engages with the guide means of the housing member, and the developer carrier is positioned at a predetermined position. It is surprising. Therefore, the developer carrier and the back electrode can be easily and accurately aligned. Note that the guide means may be any means that engages with the above-mentioned protrusion or rod-shaped member, and may be, for example, a concave portion or a groove.

In a tenth aspect based on the eighth aspect, the developer supply unit is guided so that the developer carrier moves toward the center of the back electrode.

According to the tenth aspect, since the developer carrier is guided toward the center of the back electrode, when the developer carrier is positioned with respect to the back electrode, the radial position of the back electrode is determined. The determination and the circumferential positioning do not influence each other. Therefore, highly accurate positioning is easily performed. In the eleventh aspect based on the ninth aspect, in the ninth aspect, the guide means of the housing member comprises: an insertion portion extending in a predetermined insertion direction; and a predetermined or continuous bending of the developer carrier from the insertion portion. And a positioning section for guiding to the recording position.

According to the eleventh aspect, when mounting the developer supply unit, first, the protrusion or the rod-shaped member of the developer supply unit is engaged with the insertion portion, and the developer supply unit is moved in the predetermined insertion direction. Is inserted along. Thereafter, the protrusion or the rod-shaped member moves from the insertion portion to the positioning portion, and the developer supply unit is guided to a predetermined recording position. Here, the recording position means an appropriate position during a recording operation in which the developer is ejected to the intermediate image holding unit. As a result, the developer supply unit is easily and quickly mounted, and the developer carrier is positioned with high accuracy. Also, even if the device is configured so that the developer supply unit is inserted in an arbitrary direction, for example, in a horizontal direction, the developer carrier is eventually guided toward the center of the back electrode. The positioning of the developer carrier with respect to the back electrode in the radial direction and the circumferential direction does not affect each other, and the developer carrier and the back electrode are positioned with high precision.

In a twelfth aspect based on the eleventh aspect, the insertion portion and the positioning portion are disposed so as to extend on the same straight line.

According to the twelfth aspect, the developer supply unit is straightened toward the recording position.

According to a thirteenth invention, in the first to twelfth inventions, the image forming apparatus further comprises a plurality of recording units each including the developer carrier, the developer passage control member, and the back electrode, and The means is provided so as to sequentially travel between the developer passage control member of each of the recording sections and the back electrode.

According to the thirteenth aspect, in a device including a plurality of recording units, the head interval of each recording unit can be stabilized. If the developer in the recording section is made of a different color, a high-quality color image with excellent color balance is formed.

A fourteenth invention is directed to a developer carrier that carries and transports a charged developer, a back electrode disposed to face the developer carrier, the developer carrier, and the back surface. Electric An insulating substrate disposed between the electrode and a plurality of developer passage holes, and disposed around each developer passage hole in the insulating substrate and supplied with an image signal. A signal electrode; and a developer passage control member that causes the developer on the developer carrier to pass through a predetermined developer passage hole and fly toward the back electrode based on the image signal. 1, a plurality of recording units including at least the second and third recording units, and each of the recording units so as to generate an intermediate image by receiving a developer from the developer passage control member of each of the recording units. An image comprising: an intermediate image holding means disposed so as to sequentially travel between a developer passage control member and a back electrode; and a transfer means for transferring an intermediate image on the intermediate image holding means to a recording medium. A forming device, wherein at least each of the back electrodes of the first, second, and third recording units is The contact portion of the back electrode of the second recording unit is different from the contact portion of the back electrode of the first recording unit and the contact unit of the third recording unit. It is arranged so as to protrude toward the intermediate image holding belt side from an imaginary line connecting the contact portion of the back electrode.

According to the fourteenth aspect, each of the back electrodes of the first to third recording units has a contact portion, and the back electrode of the second recording unit protrudes toward the intermediate image holding unit. Therefore, the intermediate image holding unit contacts at least the back electrode of the second recording unit so as to have a predetermined winding angle. As a result, the intermediate image holding means travels in a state in which it is securely in contact with the back electrode, so that the head interval is stabilized. Therefore, recording conditions are highly uniform, and a high level of image quality is formed.

A fifteenth aspect of the present invention provides a developer carrier that carries and transports a charged developer, a back electrode disposed so as to face the developer carrier, the developer carrier and the back surface. An insulating substrate provided between the electrode and the plurality of developer passage holes, and an image signal provided around the respective developer passage holes in the insulating substrate. And a developer passage control member that causes the developer on the developer carrier to pass through a predetermined developer passage hole and fly toward the back electrode based on the image signal. Developing a plurality of recording units including at least a first and a second recording unit, and developing each of the recording units so as to generate an intermediate image by receiving a developing agent from a developer passage control member of each of the recording units; Intermediate image holding hand disposed so as to run sequentially between the agent passage control member and the back electrode When, the intermediate image holding means A guide member for guiding the intermediate image holding means to the first recording section so that the intermediate image travels from the first recording section toward the second recording section; An image forming apparatus including a transfer unit for transferring the image to the intermediate image holding unit, wherein at least the guide member and each of the back electrodes of the first and second recording units have a contact portion that contacts the intermediate image holding unit. On the other hand, the intermediate image holding belt has a contact portion of the back electrode of the first recording unit which is larger than an imaginary line connecting the contact portion of the guide member and the contact portion of the back electrode of the second recording unit. It is arranged to protrude to the side.

According to the fifteenth aspect, the guide member and each of the back electrodes of the first and second recording units include an abutting portion, and the back electrode of the first recording unit protrudes toward the intermediate image holding unit. Therefore, the intermediate image holding unit contacts at least the back electrode of the first recording unit so as to have a predetermined winding angle. As a result, the intermediate image holding means travels in a state in which the intermediate image holding means is securely in contact with the back electrode, so that the head interval is stabilized.

In a sixteenth aspect based on the fourteenth or fifteenth aspect, the mutual positional relationship between the developer carrying member, the developer passage control member, the intermediate image holding means, and the back electrode of each of the recording units is a plurality. The numbers are the same between the recording units.

According to the sixteenth aspect, the recording conditions are made uniform among the plurality of recording sections, and a high-level image is formed.

In a seventeenth aspect based on the sixteenth aspect, each of the recording units includes a developer supply unit having a storage container for storing a developer and having the developer carrier attached thereto. The direction in which the developer supply unit is inserted and removed is different for each developer supply unit.

According to the seventeenth aspect, the restriction on the insertion / removal direction of the developer supply unit is reduced, and the degree of design freedom of the apparatus is increased.

An eighteenth invention is based on the sixteenth invention, wherein each of the recording units has a container for accommodating a developer and has a developer supply unit attached with the developer carrier. A housing member to which the developer supply unit is detachably attached, wherein each of the developer supply units is provided with a first engaging means, and each of the housing members has a developer passage therethrough. A second engaging means is provided for guiding the insertion / removal of the developer supply unit by engaging the first engaging means with the control member, and is mounted on the upper side of the apparatus main body. The developer supply units are non-parallel to each other so that the direction of insertion and removal of the developer supply unit is larger than the direction of insertion and removal of the developer supply unit attached to the lower part of the apparatus main body. It is what is arranged.

According to the eighteenth aspect, for example, the developer supply unit mounted on the lower side of the apparatus main body is inserted into or removed from the front, rear, or side, and the developer supply unit mounted on the upper side of the apparatus main body. A configuration in which the developer supply unit can be easily removed and inserted can be obtained, for example, by inserting and removing the unit upward. According to a nineteenth aspect, in the eighteenth aspect, the first engaging means comprises a protrusion or a rod-like member projecting from the developer supply unit, and the second engaging means comprises the protrusion or the rod-like member. It comprises guide means for guiding the members.

According to the nineteenth aspect, at the time of mounting the developer supply unit, the protrusion or the rod-shaped member of the developer supply unit engages with the guide means of the housing member, and the developer supply unit is positioned at a predetermined position. You will be guided.

According to a twenty-first aspect, in the sixteenth aspect, the recording units each include a developer supply unit having a storage container for storing a developer and having the developer carrier attached thereto. The directions in which the developer supply unit is inserted and removed are parallel to each other.

According to the twenty-second aspect, the size of the apparatus can be reduced by reducing the dead space between the developer supply units.

According to a twenty-first aspect, in the sixteenth aspect, the recording units each include a developer supply unit having a storage container for storing a developer and having the developer carrying member attached thereto; A housing member for detachably mounting the developer supply unit; and a projection or a rod-like member projecting from the developer supply unit is provided on each of the developer supply units. In addition, a developer passage control member is attached to each of them, and an insertion portion extending in a predetermined insertion direction, and a positioning portion that continuously or bends from the insertion portion to guide the developer carrier to a predetermined recording position. Guide hand for the projection or rod-shaped member including While the step is formed, the insertion portions of the housing member of the recording unit are formed parallel to each other.

According to the twenty-first aspect, the size of the apparatus can be reduced by reducing the dead space between the developer supply units.

According to a twenty-second invention, in the twenty-first invention, the insertion portion and the positioning portion are arranged so as to extend on the same straight line.

According to the twenty-second aspect, the developer supply unit is straightened toward the recording position.

According to a twenty-third aspect, in the sixteenth aspect, each of the recording units has a container for accommodating a developer, and a developer supply unit to which the developer carrier is attached. A support portion provided on the developer supply unit, the support portion supporting the developer passage control member on the developer supply unit so as to cover the front end side of the developer carrier, and the developer supply unit includes: Engagement means comprising protrusions or rod-shaped members protruding from the developer supply unit are provided, and a housing member provided with a plurality of guide means for guiding the engagement means of each of the developer supply units is provided. The guide means of the housing member includes: an insertion portion extending in a predetermined insertion direction; and a positioning portion continuously or bent from the insertion portion to guide each of the developer carriers to a predetermined recording position. Have .

According to the twenty-third aspect, a configuration is provided in which the developer passage control member is integrated with the developer supply unit, and the developer passage control member and the developer supply unit can be simultaneously replaced. According to a twenty-fourth invention, in any one of the twenty-first to twenty-third inventions, the insertion portion may move the developer supply units in the horizontal direction when the developer supply units are mounted. It is formed so as to guide obliquely downward or downward.

According to the twenty-fourth aspect, the developer supply unit can be easily mounted.

In a twenty-fifth aspect based on any one of the twenty-first to twenty-third aspects, the insertion portion is constituted by a horizontal guide portion extending in a horizontal direction.

According to the twenty-fifth aspect, all the developer supply units are inserted and removed in the horizontal direction, and the size of the apparatus can be reduced by reducing the dead space. In a twenty-sixth aspect based on any one of the seventeenth to twenty-third aspects, the developer supply units of the recording unit are formed in the same shape.

According to the twenty-sixth aspect of the present invention, it is not necessary to manufacture a different type of unit for each recording unit. For example, a mold cost when a container for the developer supply unit is manufactured by resin molding, and the like. Therefore, manufacturing costs can be reduced.

According to a twenty-seventh aspect, in any one of the seventeenth to twenty-third aspects, the developer carrier of each of the developer supply units, the developer passage control member, the intermediate image holding unit, and the back electrode Is the same among a plurality of developer supply units, while the positional relationship of the storage container with respect to the back electrode and the intermediate image holding means is different for each developer supply unit.

In a twenty-eighth aspect based on the twenty-seventh aspect, the shape and dimensions of the container of the developer supply unit are the same among a plurality of developer supply units, while the shape and dimensions of the container are the same as the center of the developer carrier. The positional relationship between the imaginary line connecting the center of the developer passage hole of the developer passage control member and the storage container is different for each developer supply unit. According to each of the twenty-seventh and twenty-eighth inventions, for example, even when the insertion / removal direction of the developer supply unit is different between a plurality of recording units, the developer carrying member and developer passage control of each recording unit Since the means, the intermediate image holding means and the back electrode are in a predetermined positional relationship, good recording is possible.

A twentieth invention is the invention according to any one of the eighteenth, nineteenth, and twenty-first to twenty-third inventions, wherein the developer supply unit of each of the recording units includes a housing for another recording unit. The developer supply unit has a different shape or size from the developer supply unit of another recording unit so that it cannot be inserted into or removed from a member.

In a thirtieth aspect based on the eighteenth aspect, the first engagement means of the developer supply unit of each of the recording parts is not capable of engaging with the second engagement means of the other recording part. The other recording unit is different in shape or size from the first engaging means of the developer supply unit. According to a thirty-first aspect, in the twenty-third aspect, the engaging means of the developer supply unit of each recording section is related to a guide means for guiding the engaging means of the developer unit of another recording section. Failure For the sake of simplicity, the shape and dimensions of the recording unit are different from those of the engaging means of the developer supply unit of the other recording unit.

According to each of the twenty-ninth to thirty-first inventions, erroneous insertion of the developer supply unit is reliably prevented.

A thirty-second invention is directed to a developer supply unit having a storage container for storing a developer and a developer support for transporting the developer in the storage container while supporting the developer. A back electrode disposed between the developer carrier, the image receiving member disposed between the developer carrying member and the back electrode, a rear electrode disposed between the developer carrying member and the image receiving member, and An insulating substrate having a plurality of developer passage holes formed therein, and a signal electrode disposed around each developer passage hole of the insulation substrate and supplied with an image signal; A developer passage control member that causes the developer on the developer carrier to fly through a predetermined developer passage hole based on an image signal and adhere to the image receiving body; The developer carrier is formed detachably with respect to the apparatus main body, and the developer carrier is provided with the developer supply unit. The portion of the developer passage control member facing the developer passage hole when the cartridge is mounted on the apparatus main body is formed so as to convey the developer vertically downward or substantially vertically downward. Things. According to the thirty-second aspect, when a foreign substance or the like clogged between the developer passage control member and the developer carrying member is removed, the foreign substance or the like falls by gravity. At this time, since the transport direction of the developer carrier is vertically downward or substantially vertically downward, the foreign matter and the like that has been removed once are transferred again to the developer passage control member and the developing device by the transport operation of the developer carrier during the recording operation. There is no return to the agent carrier and no clogging between them. Therefore, damage to the developer passage control member, electrical short-circuit between the developer passage control member and the developer carrier, and the like are prevented.

In the above invention and each of the following inventions, the image receiving member may be an intermediate image holding means such as an intermediate image holding belt or a recording medium such as a recording paper. That is, the image forming apparatus and the following image forming apparatuses may be those that transfer an intermediate image to a recording medium or those that directly form an image on a recording medium.

The thirty-third invention is directed to a storage container for storing the developer and the developer in the storage container. A developer supply unit having a developer carrier conveyed from the developer carrier, a back electrode disposed so as to face the developer carrier, and a rear electrode disposed between the developer carrier and the back electrode. An image receiving member, an insulating substrate provided between the developer carrying member and the image receiving member and having a plurality of developer passage holes formed therein, and a passage of each developer through the insulating substrate. A signal electrode provided around the hole and supplied with an image signal, and flying the developer on the developer carrier so as to pass through a predetermined developer passage hole based on the image signal. And a developer passage control member for causing the developer supply unit to adhere to the image receiving member, wherein the developer supply unit is formed so as to be freely detachable in a horizontal direction or a substantially horizontal direction with respect to the apparatus main body.

According to the thirty-third aspect, when the developer supply unit is mounted on the apparatus main body, it is possible to prevent foreign substances from freely falling from the outside and adhering to the developer passage control member or the like. According to a thirty-fourth aspect, the present invention provides a developer supply unit having a container for storing a developer and a developer carrier for carrying the developer in the container while carrying the developer. A back electrode disposed so as to face, an image receiving member disposed between the developer carrying member and the back electrode, and a rear electrode disposed between the developer carrying member and the image receiving member. And an insulating substrate having a plurality of developer passage holes formed therein, and a signal electrode provided around each developer passage hole of the insulation substrate and supplied with an image signal, A developer passage control member for causing the developer on the developer carrier to fly through a predetermined developer passage hole based on the image signal and attaching the developer to the image receiver; and inserting the developer supply unit Unit is provided to allow the developer supply unit to be inserted and withdrawn. The unit main body and the developer supply unit are closed so that the unit insertion slot of the apparatus main body is closed when the developer supply unit is detached from the apparatus main body. It is provided with a shutter for opening and closing.

According to the thirty-fourth aspect, when the developer supply unit is separated from the apparatus main body, the shut-off means is closed, so that the developer passage control member is not exposed to the outside of the apparatus. Therefore, foreign matter is prevented from entering the developer passage control member from outside the apparatus. Further, there is no possibility that the user's hand directly touches the developer passage control member or the like.

According to a thirty-fifth aspect, a container for storing the developer and the developer in the container are supported. A developer supply unit that has a developer carrying member that is conveyed from the main body and that is detachably formed in the apparatus main body; a back electrode that is disposed to face the developer carrying member; An image receiving body disposed between the body and the back electrode; and an insulating substrate provided between the developer carrier and the image receiving body and having a plurality of developer passage holes formed therein, A signal electrode disposed around each developer passage hole of the insulating base material and supplied with an image signal; and developing the developer on the developer carrier based on the image signal in a predetermined manner. A developer passage control member that is caused to fly through the developer passage hole and adhere to the image receiving member; and a developer supply unit when the developer supply unit is not attached to the apparatus main body or when the developer supply unit is not attached to the apparatus main body. When mounting to the device body, the developer passage control member Cleaning means for performing a cleaning operation for removing adhering foreign matter.

According to the thirty-fifth aspect, even when a foreign matter adheres to the developer passage control member, the foreign matter can be removed without manual intervention.

In a thirty-sixth aspect based on the thirty-fifth aspect, the cleaning means includes a vibrating means for applying mechanical vibration to the developer passage control member.

According to the above-described thirty-sixth aspect, by applying mechanical vibration to the developer passage control member, foreign matters adhering to and around the developer passage hole of the developer passage control member can be easily removed. You. Therefore, even when foreign matter adheres to the developer passage control member during the replacement operation of the developer supply unit, the foreign matter can be removed without manual operation. According to a thirty-seventh aspect, there is provided a developing device having a container for accommodating a developer and a developer carrying member for carrying the developer in the container while carrying the developer, wherein the developing container is detachably attached to the apparatus body. A developer supply unit, a back electrode arranged to face the developer carrier, an image receiver arranged between the developer carrier and the back electrode, and the developer carrier. An insulating substrate disposed between the image receiving member and the plurality of developer passage holes, and an image signal is provided around the respective developer passage holes of the insulating substrate. A signal electrode; and a developer passage control member for causing the developer on the developer carrier to fly through a predetermined developer passage hole and adhere to the image receiver based on the image signal. The developer supply unit is provided with the developer when attached to the apparatus main body. To perform conveyance movements to lifting body It is formed as follows.

According to the thirty-seventh aspect of the invention, even when a foreign substance has adhered to the developer carrying member before the developer supply unit is mounted, the foreign substance is not attached when the developer supply unit is mounted. Since the developer is transported in the transport direction of the developer carrier, there is no clogging between the developer passage control member and the developer carrier. The developer supply unit is provided with a developer supply roller for supplying the developer in the container to the developer carrier, a regulating blade for regulating the amount of developer carried on the developer carrier, and the like. In such a case, the conveyed foreign matter is regulated by the developer supply roller and the regulating blade, so that the foreign matter is reliably prevented from returning between the developer passage control member and the developer carrier. You.

In a thirty-eighth aspect based on the thirty-second, thirty-fourth, thirty-fifth, or thirty-seventh aspect, the developer supply unit is formed so as to be capable of being inserted into and removed from the apparatus main body in a horizontal direction or a substantially horizontal direction. Is what is being done.

According to the thirty-eighth aspect, when the developer supply unit is mounted on the apparatus main body, it is possible to prevent foreign substances from freely falling from the outside and adhering to the developer passage control member or the like. In addition, even when foreign matter adheres to the shutter means, the foreign matter does not drop onto the developer passage control member due to gravity due to the opening and closing operation of the shutter means.

A thirty-ninth aspect is the invention according to the thirty-second, thirty-third, thirty-fifth, or thirty-seventh aspect, wherein a unit insertion slot for inserting the developer supply unit is formed in the apparatus main body, Opening and closing the developer supply unit so as to close the unit supply opening when the developer supply unit is detached from the apparatus main body. It is provided with shutter means.

According to the thirty-ninth aspect, when the developer supply unit is detached from the apparatus main body, the shirt closing means is closed, so that the developer passage control member is not exposed to the outside of the apparatus. Therefore, foreign matter is prevented from entering the developer passage control member.

A 40th invention is the 32nd, 33rd, 34th or 37th invention, wherein the developer supply unit is not provided with the developer supply unit. At the time of mounting the developer supply unit to the apparatus main body, Cleaning means for performing a cleaning operation for removing foreign matter adhering to the member is provided.

According to the forty-fifth aspect, foreign substances can be removed without manual intervention. Also, since the removed foreign matter is removed in the downward direction, which is the downstream side in the rotation direction of the developer carrying member during recording, the removed foreign matter is again removed during the recording operation by the developer carrying member and the developer passage control member. Will not return to the position between.

According to a forty-first aspect, in the forty-third aspect, the cleaning means includes a vibration means for applying mechanical vibration to the developer passage control member.

According to the forty-first aspect, by applying mechanical vibration to the developer passage control member, foreign matters adhering to and around the developer passage hole of the developer passage control member can be easily removed. You. Therefore, even when foreign matter adheres to the developer passage control member during the replacement operation of the developer supply unit, the foreign matter can be removed without manual operation. Also, since the removed foreign matter is removed in the downward direction, which is the downstream side in the rotation direction of the developer carrying member during recording, the removed foreign matter is again removed during the recording operation by the developer carrying member and the developer passage control member. It does not occur that the developer carrier and the control electrode of the developer passage control member are electrically short-circuited due to the destruction of the insulating layer.

According to a forty-second invention, in the thirty-fifth invention, the apparatus main body includes a recovery unit that recovers the developer removed from the developer passage control member.

According to the forty-second aspect, since the developer removed from the developer passage control member is collected by the collection part, the developer does not return again between the developer passage control member and the developer carrier. According to a forty-third aspect, in the thirty-second, thirty-third, thirty-fourth, or thirty-fifth aspects, the developer supply unit is transported to the developer carrier in accordance with attachment to the apparatus main body. It is designed to exercise.

According to the forty-third aspect, even when a foreign substance has adhered to the developer carrying member before the developer supply unit is mounted, the foreign substance is not attached when the developer supply unit is mounted. Since the developer is transported in the transport direction of the developer carrier, there is no clogging between the developer passage control member and the developer carrier. A forty-fourth invention is based on the thirty-sixth invention, wherein the vibration means extends in an arrangement direction of an ultrasonic vibration generator that generates ultrasonic vibration, and a developer passage hole of the developer passage control member. Is fixed to the developer passage control member beside the developer passage hole, and one end of the ultrasonic vibration generator transmits the ultrasonic vibration to the developer passage control member so as to transmit the ultrasonic vibration to the developer passage control member. And a vibrating body connected to the vibration generating body.

According to the forty-fourth aspect, the ultrasonic vibration generated by the ultrasonic vibration generator is transmitted to the developer passage control member via the vibrator, and the periphery of the developer passage hole of the developer passage control member and Foreign matter adhering to the inside is removed.

According to a forty-fifth aspect, in the thirty-seventh aspect, when the developer supply unit is attached to or detached from the apparatus main body, the developer carrier performs a transport motion in a direction opposite to a developer transport direction. It has a blocking means for blocking.

According to the forty-fifth aspect, when the developer supply unit is attached or detached, the developer carrier does not perform the transport movement in the direction opposite to the developer transport direction, so that leakage of the developer from the developer supply unit is prevented. Is done.

In a forty-sixth aspect based on the thirty-seventh aspect, the developer carrier is constituted by a carrier roller, and the carrier roller is provided with a rotating gear means that rotates with the carrier roller. The apparatus main body is provided with rack means which engages with the rotating gear means so as to rotate the carrier roller in a developer conveying direction with the mounting of the developer supply unit.

According to the forty-sixth aspect, with a simple mechanism, the carrying roller can be rotated in the developer transport direction when the developer supply unit is mounted.

In a forty-seventh aspect based on the forty-sixth aspect, the support roller is provided in the container so that a part of the roller is exposed to the outside of the container, and A portion facing the developer passage hole is formed so as to convey the developer vertically downward, and the apparatus main body is provided with a housing member formed so as to be capable of horizontally inserting and removing the storage container, The rotating gear means is disposed coaxially with the support roller, and the rack means is disposed on an inner lower surface of the housing member. According to the forty-seventh aspect, with a simple mechanism, the carrying roller can be automatically rotated in the developer conveying direction when the developer supply unit is mounted.

A forty-eighth invention is based on the forty-sixth invention, wherein the rotating gear means is formed by a reduction gear that reduces a rotational driving force due to engagement with the rack means and transmits the reduced driving force to the carrying roller. Things.

According to the forty-eighth aspect, the developer supply unit can be inserted with a small force even when the load torque of the support roller when the developer supply unit is inserted is large.

According to the present invention, in all of the plurality of developer supply units, the interval between the intermediate image holding means and the developer passage control member is stabilized with high accuracy, so that a plurality of developer supply units can be provided. Thus, the recording conditions can be made uniform. Therefore, a high-quality color image with excellent color balance can be formed. In addition, an image forming apparatus that is easy to use and easy to downsize can be realized.

Further, according to the present invention, it is possible to prevent foreign matter from adhering to the developer carrier and the developer passage control member during replacement of the developer supply unit and cleaning work of the print head. . Further, even if foreign matter adheres, the foreign matter can be easily removed. Therefore, it is possible to provide a highly reliable image forming apparatus that does not cause deterioration in image quality or missing dots. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a sectional view showing a schematic configuration of the image forming apparatus according to the first embodiment.

FIG. 2 is a cross-sectional view illustrating a schematic configuration of the image forming apparatus according to the first embodiment, and illustrates a state before a developing device is mounted.

FIG. 3 is an enlarged sectional view showing a print head of the image forming apparatus according to the first embodiment.

4 (a) is a cross-sectional view of the front side of the control plate, FIG. 4 (b) is a cross-sectional view taken along line AA of FIG. 4 (a), and FIG. 4 (c) is a cross-sectional view of the back side of the control plate. FIG. 5 is a schematic diagram showing an arrangement state of the back electrode.

FIG. 6 is a schematic diagram for explaining a relationship between a shift amount and a shift angle of a contact portion between the back electrode and the intermediate image belt.

FIGS. 7A to 7D are perspective views of the image forming apparatus.

FIG. 8 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the second embodiment.

FIG. 9 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the second embodiment, and illustrates a state before a developing device is mounted.

FIG. 10 is an enlarged sectional view showing a print head of the image forming apparatus according to the second embodiment.

FIG. 11 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the third embodiment. FIG. 12 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the third embodiment, and illustrates a state before a developing device is mounted.

FIG. 13 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the fourth embodiment. FIG. 14 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to the fourth embodiment, and illustrates a state before a developing device is mounted.

FIG. 15 is an enlarged sectional view showing a print head of the image forming apparatus according to the fourth embodiment.

FIG. 16 is an enlarged cross-sectional view of the print head of the image forming apparatus according to the fourth embodiment, showing a state in which the developing device is being mounted. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First embodiment>

First, a first embodiment of an image forming apparatus according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the image forming apparatus of this embodiment includes print heads 1a to 1d of four colors of yellow, magenta, cyan, and black, and each print head 1a to 1d. 1 d This device forms an intermediate image on the intermediate image belt 7 by sequentially injecting toner of each color onto the intermediate image belt 7, and transfers the intermediate image to recording paper 50 to form a color image.

Inside the substantially rectangular parallelepiped main body case 3 placed on the floor surface, a single main housing member 2 in which four housing members 2 a to 2 d are integrally formed is provided. . The main housing member 2 is configured to be detachable from the main body case 3. Each of the housing members 2a to 2d is formed of a cylindrical container having the same shape. As shown in FIGS. 1 and 2, for the housing members 2a to 2d, the developer supply containing the toners 8a to 8d of the four colors of yellow, magenta, cyan and black respectively is supplied. Units (hereinafter referred to as developing units) 5a to 5d are provided so as to be freely inserted and removed, respectively.

Since the configuration of each of the print heads 1a to 1d is basically the same, the configuration of the print head 1a will be described in detail with reference to FIG. The description of Id is omitted. As shown in FIG. 3, the print head la includes a housing member 2a having a developer insertion slot 60 provided at the right end and a developer supply opening 10 formed at the left end, and a housing member 2a. It has a control plate 4 disposed on the left outer surface so as to cover the developer supply opening 10, and a developing device 5a removably mounted in the housing member 2a. On the left side of the control plate 4, a back electrode 6a is disposed at an appropriate distance from the control plate 4. The intermediate image belt 7 is disposed so as to run between the back electrode 6a and the control plate 4.

The developing device 5a includes a cylindrical storage container 9 for storing the toner 8a as a developer, and a supporting roller 11 provided on a distal end side (the left side in FIG. 3) of the storage container 9. . The holding roller 11 holds the toner 8 a in the storage container 9 and conveys the toner 8 a to the vicinity of the toner passage hole 23 of the control plate 4 described later. The carrying roller 11 is attached to the container 9 so that a part of the roller protrudes from the tip of the container 9. Thereby, when the developing device 5a is mounted, the tip of the support roller 11 is positioned so as to face the developer supply opening 10. The container 9 of the developing device 5a has a regulating blade 12 for regulating the toner layer on the supporting roller 11 so as not to be thick, and the toner 8a in the container 9 by stirring. A supply roller 13 is provided for supplying to the support roller 11 after being charged by friction. The carrying roller 11 is formed in a cylindrical or columnar shape having a central axis extending in the horizontal direction (the direction of the front and back of the sheet of FIG. 3). As a material of the supporting roller 11, a metal such as aluminum or iron, an alloy, or the like can be preferably used. In the present embodiment, an aluminum cylindrical roller having an outer diameter of 2 O mm and a thickness of 1 mm is used.

The regulating blade 12 is made of an elastic member such as urethane, and has a hardness of 40 to 80 degrees (JISK 6301 A scale) and a free end length (length of a portion protruding from the mounting portion). 5 mn! An appropriate linear pressure on the carrying roller 11 is 5 g / cm to 40 g / cm, and a roller which forms one to three layers of the toner 8 a on the carrying roller 11 is particularly preferable. The supply roller 13 is provided with a synthetic rubber such as foamed urethane of about 2 to 6 mm on a metal shaft of iron or the like (in this embodiment, a metal shaft having a diameter of 8 mm), and has a hardness of about 30 degrees. (Measured using a JISK 6301 A scale method on a roller-shaped one). The supply roller 13 assists the charging of the toner 8a and controls the supply of the toner 8a. In order to satisfactorily supply and charge the toner 8a, the amount of the supply roller 13 biting into the support roller 11 is particularly preferably about 0.1 mm to 2 mm. The toner 8a is sandwiched between the carrying roller 11 and the regulating blade 12, where the toner 8a receives a small amount of agitation and receives electric charge from the carrying roller 11 to be charged. In this embodiment, a non-magnetic material having an average particle diameter of 8 μm having a negative charge of −10 ° C./g is used as the toner 8 a.

In addition, the carrying roller 11, the regulating blade 12, and the supply roller 13 may be electrically grounded, or may be configured to receive a DC or AC voltage. Further, the regulating blade 12 may be electrically floated. In the present embodiment, the regulating blade 12 is configured to be electrically floated.

Axial direction of the carrying roller 11 (front and back sides of the paper surface in Fig. 3) Outside of both ends, the gap between the carrying roller 11 and the back electrode 6a is maintained at a predetermined distance by contacting the back electrode 6a. As the first spacer to be possessed, a regulatory collar 14 is provided. The regulating collar 14 is formed in a cylindrical shape concentric with the carrying roller 11. Regulations 1 to 4 The outer periphery is in contact with the back electrode 6a, and the inner periphery is fixed in contact with the outer periphery of the carrying roller 11 or the outer periphery of the guide shaft 15 extending to both sides from the carrying roller 11 C The distance between the back electrode 6a and the supporting roller 11 is set to 150 5π! The interval is set to a predetermined interval of up to 10000〃m (350 im in the present embodiment). An opening (not shown) through which the regulating collar 14 penetrates is formed on both sides of the developer supply opening 10 of the housing member 2a (both ends in the front and back directions of the paper of FIG. 3). .

Guide shafts 15 concentric with the carrying roller 11 are provided on both sides of the carrying roller 11 in the axial direction so as to protrude from both ends of the container 9. Guide grooves 17 for guiding the guide shaft 15 are formed in both end walls 16 of the housing member 2a. The guide groove 17 guides the guide shaft 15 so that the carrying roller 11 is positioned at a predetermined mounting position (recording position). In the present embodiment, the guide groove 17 is formed by a straight groove. The back electrode 6a is formed by dispersing a conductive filler in a metal or resin material, and is a cylindrical or cylindrical electrode roller having a central axis extending in the horizontal direction. The back electrode 6a forms an electric field between the supporting roller 11 and the toner to attract the toner 8a to the back electrode 6a. The DC voltage applied to the back electrode 6a is preferably about 500 V to 2000 V, and in the present embodiment, a voltage of 100 V is applied. As shown in FIG. 1, the rear electrodes 6a to 6d are disposed in the main body case 3, and the main housing member 2 is removably positioned and fixed to the right of the rear electrodes 6a to 6d. I have.

A fixing portion 19 for fixing one end of the control plate 4 is formed on one side of the developer supply opening 10 side of the housing member 2a, and the other end of the control plate 4 is formed on the other side. A part of the stay 20 is formed to bend rightward to the right. The stay part 20 has a substantially semicircular cross section. On the right side of the stay part 20, a pair of spring hooks 21 are provided at a predetermined interval from the stay part 20. As described above, since the housing member 2a is detachable from the main body case 3 integrally with the other housing members 2b, 2c, and 2d, the housing member 2a is removed from the main body case 3. Thus, the cleaning operation of the control plate 4 can be performed outside the main body case 3. Therefore, the cleaning operation of the control plate 4 is easily performed. When mounting the housing member 2a to the main body case 3, the control plate 4 It will be automatically positioned at a predetermined position with respect to 6a.

As shown in FIG. 4, the control plate 4 includes a sheet-like insulating base material 22 and a plurality of image signal electrodes.

3 and 9 are provided. A large number of toner passage holes 23 are formed in the insulating base material 22 at predetermined intervals along the width direction of the intermediate image belt 7 (see FIG. 3). Columns 24 are formed. The image signal electrode 39 is formed in a ring shape on the surface of the insulating base material 22 (the surface facing the carrying roller 11) so as to surround each toner passage hole 23. On the other hand, on the back surface of the insulating base material 22 (the surface facing the intermediate image belt 7), an aperture formed so that only the portions corresponding to the toner passage holes 23 and the image signal electrodes 39 are voids. An electrode 40 is provided.

The insulating substrate 22 is preferably made of a material such as polyimide or polyethylene terephthalate, and has a thickness of 1! ~ 100zm is preferred. In the present embodiment, the insulating base material 22 is made of polyimide having a thickness of 50 / m, and the diameter of the toner passage hole 23 is set to 145 m. The image signal electrode 39 is made of a metal foil such as copper having a thickness of about 5 to 30 μm, and is formed in a ring shape having an inner diameter of 150 μm and an outer diameter of 250 μm. I have. The gap of the aperture electrode 40 is formed in a circular shape having an inner diameter of 250 m. Each electrode 39,

An insulating layer 41 made of a thin resin layer having a thickness of l / m to 10〃m is provided on the surface of 40. The image signal electrodes 39 are independently connected to image signal output units (not shown) for supplying image signals to the image signal electrodes 39 via the lead wires 39a. It is preferable that a voltage of 400 V or less is applied to the image signal electrode 39. In the present embodiment, a voltage of 300 V is applied to an image signal electrode that ejects toner to the intermediate image belt 7, and a voltage of −100 V is applied to an image signal electrode that does not eject toner. You.

As shown in FIG. 3, one end of the control plate 4 is fixed to a fixing portion 19 of the housing member 2a with fixing screws 25. The other end of the control plate 4 is temporarily bent by the stay part 20, and the tip is locked to a spring hook 21 via a tension spring 26. As a result, a tensile tension acts on the control plate 4 so that the control plate 4 does not warp or bend. Further, the control plate 4 is provided with a spacer 27 as a second spacer on the inner surface on the upper side in the rotation direction of the supporting roller 11 from the toner passage hole array 24. This speaker 2 7 This is for providing a predetermined interval between the carrying roller 11 (strictly speaking, the toner layer on the carrying roller 11) and the control plate 4. As a result, when the developing device 5a is mounted on the housing member 2a, the regulating collar 14 comes into contact with the back electrode 6a, and the distance between the carrying roller 11 and the back electrode 6a becomes a predetermined distance. At the same time, the outer peripheral surface of the carrying roller 11 comes into contact with the spacer 27. At this time, a pressing force acts on the spacer 27 from the carrying roller 11, and the tension spring 26 suspended at the end of the control plate 4 expands. As a result, the tension of the tension spring 26 is controlled. The control plate 4 is transmitted to the plate 4 and is brought into close contact with the carrying roller 11 via the spacer 27 over the entire width. The gap between the toner layer on the carrying roller 11 and the control plate 4 is automatically set to a predetermined interval in the range of 0 to 200 zm by the spacer 27. In the present embodiment, this interval is set to 50 m.

According to the fixing method described above, the control plate 4 is positioned and fixed with high accuracy in a state where the developing device 5a is mounted on the housing member 2a. That is, the toner passage hole array 24 is parallel to the axis of the carrying roller 11, and when there are a plurality of toner passage hole arrays 24, the passage hole arrays 24 are precisely parallel to each other. Will be in parallel.

As shown in FIG. 1, the inside of the main body case 3 is endless so as to run sequentially between the control plate 4 mounted on each of the housing members 2a to 2d and the back electrodes 6a to 6d. A belt-shaped intermediate image belt 7 is provided. Reference numerals 29 and 30 denote a pair of belt rollers around which the intermediate image belt 7 is wound. A transfer roller for transferring the toner image formed on the surface of the intermediate image belt 7 to the recording paper 50 is provided for the belt roller 29 located downstream of the housing members 2 a to 2 d in the belt traveling direction. 31 is disposed so as to face the belt roller 29.

The back electrodes 6a to 6d of the print heads 1a to 1d are arranged in a ridge between the belt roller 29 and the belt roller 30 so as to swell toward the main housing member 2. It has been done. That is, the back electrodes 6 b and 6 c other than the back electrodes 6 a and 6 d located at both ends protrude more toward the intermediate image belt 7 than the imaginary line connecting the belt contact portions of the adjacent back electrodes. Are arranged as follows. Specifically, for example, as schematically shown in FIG. 5, the contact portion 70b of the back electrode 6b is formed by a contact portion 70a of the back electrode 6a and a contact portion 7a of the back electrode 6c. 0 c and Projecting from the imaginary line 71 connecting the intermediate image belt 7 side.

The rear electrodes 6a to 6d are arranged as described above, so that each of the rear electrodes 6a to 6d has a predetermined winding angle 6> with the rear surface of the intermediate image belt 7. In contact. Thereby, a large contact area between the intermediate image pelt 7 and the back electrodes 6a to 6d is ensured. Therefore, even if the rear electrodes 6a to 6d are displaced in the axial direction, and even if there is some error in the toner passage hole 23 of the control plate 4, the toner passage hole 23 is always in the middle. It will be in contact with the back electrode 6 a to 6 d of the image pelt 7. In particular, in the present embodiment, the developing devices 5a to 5d and the main housing member 2 have a detachable structure in which the rear electrodes 6a to 6d can be freely attached and detached. If not, the positions of the toner passage holes 23 of the respective developing devices 5a to 5d are likely to shift, and as a result, the distance between the toner passage holes 23 and the intermediate image pelt 7 tends to be uneven. However, in the present embodiment, since the back electrodes 6a to 6d are arranged as described above, even if the position of the toner passage holes 23 is slightly shifted during mounting, the toner passage holes 23 and The interval between the intermediate image belt 7 and the intermediate image belt 7 is maintained at a predetermined interval. Even if the rear electrodes 6a to 6d are displaced in the axial direction, or if there are slight manufacturing errors in the rear electrodes 6a to 6d, the intermediate image belt 7, etc., the toner passage holes The interval between 23 and the intermediate image belt 7 is kept at a predetermined interval.

The value of the wrap angle 0 is preferably 2 ° or more so that the back electrodes 6 a to 6 d can reliably maintain the state of contact with the intermediate image belt 7. On the other hand, from the viewpoint of miniaturization of the device, the winding angle 0 is preferably smaller, for example, the value is preferably 90 ° or less. Therefore, the value of the winding angle 0 is preferably 2 ° to 90 °, particularly preferably 2 ° to 15 °, and further preferably 2 ° to 6 °. In the present embodiment, the winding angle 0 is 3 °.

As shown in FIG. 6, for example, when the outer diameter of the back electrodes 6 a to 6 d is 20 mm and the length in the axial direction is 30 cm, both ends of the toner passage hole array 24 of the control plate 4 are In general, the positional deviation of each of them is about ± 0.1 mm, and the positioning accuracy of the control plate 4 opposed to the rear electrode 6 is expressed by the circumferential angle of the rear electrode 6. Equivalent to an angle of 0.6 °. For this reason, the winding angle 0 of the intermediate image belt 7 is set to ± 1 °, that is, 2 ° or more, as described above, so as to allow a margin of more than ± 0.6 °. As a result, the toner passage hole array 2 4 Even if there is some misalignment, the toner passage hole array 24 and the intermediate image belt 7 face each other within the range where the back electrodes 6a to 6d and the intermediate image belt 7 are in contact with each other. The spatial distance between them (that is, the head interval) can be maintained at a predetermined distance.

As shown in FIG. 1, with the arrangement of the back electrodes 6a to 6d, the housing members 2a to 2d of the print heads 1a to 1d are arranged substantially radially. The positional relationship among the carrying roller 11, the control plate 4, the intermediate image belt 7, and the back electrodes 6a to 6d is the same for all the print heads 1a to 1d. The housing members 2 a to 2 d and the control plate 4 are vertically symmetrical with respect to an imaginary line L connecting the centers of the back electrodes 6 a to 6 d and the carrying roller 11 (excluding fixed parts and the like). It has the configuration of The guide grooves 17 of each of the housing members 2a to 2d are respectively parallel to the virtual line L, and the developing devices 5a to 5d are inserted and removed in a direction parallel to the virtual line L. Will be attached and detached. Therefore, since the carrying roller 11 is guided toward the center of each of the back electrodes 6a to 6d in parallel with the imaginary line, when the carrying roller 11 is moved in the radial direction, the position in the circumferential direction follows the movement. It is possible to avoid a situation where the position is shifted. That is, the radial positioning and the circumferential positioning of the carrying roller 11 with respect to each of the back electrodes 6a to 6d do not affect each other.

As described above, in the present embodiment, the winding angle 0 of the back electrodes 6 a to 6 d of each of the print heads 1 a to 1 d is 3 ° (± 1.5 ° with respect to the virtual line L), and Since the virtual line L is horizontal in the black developing unit 5d located at the bottom, the virtual lines L of the cyan, magenta, and yellow developing units 5a, 5b, and 5d (that is, each developing unit Are 3 °, 6 °, and 9 ° respectively with respect to the horizontal line.

At the lower end of the main body case 3, a detachable paper feed tray 49 is provided, and inside this paper feed tray 49, recording paper 50 is stacked and accommodated. 51 is a paper feed roller for transporting the recording paper 50, and 52 and 53 are a paper feed guide and a transport guide for guiding the recording paper 50. A fixing roller 54 fixes the toner image transferred to the recording paper 50 by thermocompression. 55 is a paper discharge roller and 56 is a paper discharge tray. Reference numeral 37a denotes an operation unit disposed on the upper surface of the main body case 3.

As shown in Fig. 1, Fig. 2 and Fig. 4, the right wall of the main body case 3 was formed to be openable and closable. The lid is 36. Further, the lid 36 is provided with a spring member 29 a for pressing each of the developing devices 5 a to 5 d toward the control plate 4. As a result, when each of the developing devices 5a to 5d is mounted on each of the housing members 2a to 2d, each of the developing devices 5a to 5d receives a leftward pressing force from the spring member 29a. The regulating collar 14 and the back electrodes 6a to 6d, and the supporting roller 11 and the spacer 27 are in close contact with each other. Therefore, even if these components 6, 11, 14, and 27 have some dimensional errors, the carrying roller 11 and the control plate 4 and the intermediate image in each print head 1a to 1d The positional relationship between the belt 7 and the back electrodes 6a to 6d is kept at a predetermined positional relationship with high accuracy.

An operation when the developing devices 5a to 5d are mounted in the image forming apparatus having the above configuration and an operation during image formation will be described.

First, the operation when the developing units 5a to 5d are mounted will be described. When attaching the developing units 5a to 5d to the housing members 2a to 2d, the developing units 5a to 5d are engaged while the guide shaft 15 is engaged with the guide grooves 17. Slide to the left. The developing devices 5a to 5d are slid until the regulating collars 14 contact the back electrodes 6a to 6d, so that the developing devices 5a to 5d are formed of the housing members 2a to 2d. It is set at a predetermined position d (hereinafter referred to as a recording position). At this time, as shown in FIG. 1, a predetermined pressing force to the left is applied to each of the developing devices 5 a to 5 d by a spring member 29 a provided on the lid 36 of the main body case 3. 5a to 5d are held at the recording positions. Further, the guide shaft 15 and the guide groove 17 are engaged so that the center axis of the carrying roller 11 and the toner passage hole array 24 of the control plate 4 are positioned so as to be parallel to each other. In addition, the regulating collar 14 is brought into contact with the back electrodes 6a to 6d, so that the distance between the carrying roller 11 and the back electrodes 6a to 6d can be adjusted with high precision so that the distance becomes a predetermined value. Is set. At the same time, the carrying roller 11 comes into contact with the control plate 4 via the spacer 27, and the control plate 4 is pressed and displaced against the urging force of the tension spring 26. Then, the distance between the support roller 11 and the control plate 4 is set with high accuracy by the spacer 27 so as to be a predetermined value.

Next, the image forming operation will be described. When a predetermined voltage is applied to a predetermined image signal electrode 39 of the control plate 4 based on an external image signal, the carrier roller 11 and the back electrode The electric field between 6a to 6d is strengthened, or an accelerating electric field is formed between the carrier roller 11 and the image signal electrode 39. Then, directly or indirectly by these electric fields, the toners 8 a to 8 d on the supporting roller 11 are pulled toward the back electrodes 6 a to 6 d and fly from the supporting roller 11. The flying toners 8 a to 8 d pass through the toner passage holes 23 of the control plate 4 and land on the intermediate image belt 7. On the other hand, when a voltage equal to or less than a predetermined value is applied to the image signal electrode 39, the electric field formed between the carrying roller 11 and the back electrodes 6a to 6d is weakened, and the toner 8a to 8d becomes an intermediate image. Stops landing on belt 7. Thus, a toner image is formed on the intermediate image belt 7 by the landed toners 8a to 8d. The developing units 5a to 5d for each color sequentially perform such a recording operation, so that a color image combining toners 8a to 8d of yellow, magenta, cyan, and black is formed on the intermediate image belt 7. Is formed.

After the recording paper 50 in the paper feed tray 49 is taken out one by one by the paper feed roller 51, it is supplied to the transfer roller 31 by the paper feed guide 52. And this transfer roller

According to 31, the intermediate image on the intermediate image pelt 7 is transferred to the recording paper 50. The recording paper 50 to which the intermediate image has been transferred is supplied to the fixing roller 54 through the conveyance guide 53. Then, the recording paper 50 is discharged onto the discharge tray 56 by the discharge roller 55 after the toner image is fixed by the fixing roller 54.

As described above, according to the present embodiment, by simply attaching the developing devices 5a to 5d to the housing members 2a to 2d, the carrier roller 11 and the toner passage hole array 2 of the control plate 4 4 and the back electrodes 6a to 6d can be positioned in parallel and in any direction with high accuracy, and the interval between them can be set with high accuracy at a predetermined interval, so that high-quality images can be formed. Can be done.

Also, by providing the regulating collar 14 on the developing devices 5a to 5d, the regulating collar 14 is attached to the rear electrode 6 when the developing devices 5a to 5d are inserted into the housing members 2a to 2d. By simply abutting the support rollers a to d, the distance between the support roller 11 and the back electrodes 6a to 6d can be set to a predetermined distance with high accuracy. Also, even when the housing members 2a to 2d are slightly twisted or warped, the influence is not greatly affected. Therefore, the carrying roller The distance between 11 and the back electrodes 6a to 6d can be regulated with high precision for each of the developing devices 5a to 5d.

In addition, since the spacer 27 is provided inside the control plate 4, when the developing units 5a to 5d are mounted, the control plate 4 contacts the supporting roller 11 via the spacer 27. Touch As a result, the control plate 4 receives the tensile force of the tension spring 26 and receives the pressing force of the carrying roller 11 to be displaced toward the intermediate image pelt 7 so that the distance between the carrying roller 11 and the control plate 4 becomes a predetermined distance. Can be set with high precision.

Also, the back electrodes 6 a to 6 d are positioned such that a part of the back electrodes 6 a to 6 d projects with respect to the imaginary line 71 connecting the abutting portions of the adjacent back electrodes 6 a to 6 d or the belt rollers 29 and 30. Arranged in a relationship. Therefore, the intermediate image belt 7 is suspended at a constant wrap angle 6> on all the back electrodes 6a to 6d, and the intermediate image belt 7 is securely adhered to all the back electrodes 6a to 6d. It can be run stably in the state where it was done.

Further, since the toner passage hole 23 of the control plate 4 faces the position of the back electrodes 6a to 6d within the range of the winding angle Θ, the contact with the back electrodes 6a to 6d of the intermediate image belt 7 is made. You will face the touching part. Therefore, the intermediate image pelt 7 does not float from the back electrodes 6a to 6d as the vehicle travels, and the intermediate image belt 7 travels between the carrier roller 11 and the intermediate image belt 7. It can be stabilized regardless of the state.

As described above, the interval (head interval) between the control plate 4 and the intermediate image belt 7 can be stabilized in all of the plurality of developing devices 5a to 5d. 5d recording conditions can be made uniform. Therefore, a high-quality color image excellent in color balance can be formed.

Further, in the present embodiment, while the direction of insertion and removal of the developing device 5d located at the lowest stage in the main body case 3 is set to the horizontal direction, the direction of insertion and removal of the other developing devices 5c to 5a is gradually changed from the horizontal direction. The developing device 5a to 5d was substantially radially inserted in and out of the developing devices 5a to 5d as a whole. Therefore, the user can insert or remove the developing devices 5a to 5d from above or in front of the main body case 3 (right side in FIG. 1), and the developing devices 5a to 5d can be relatively easily. d can be detached. Further, in the present embodiment, since the plurality of developing devices 5a to 5d can be configured in the same shape, manufacturing costs such as a mold cost when the container 9 and the like are manufactured by resin molding are reduced. It can be significantly reduced.

In this embodiment, as shown in FIG. 7A, a cover 36 is provided in an opening formed on the front surface of the main body case 3, and the developing devices 5 a to 5 d are inserted and removed from the opening. However, the main body case 3 is not limited to such a configuration. For example, as shown in FIG. 7 (b), the lid 36 may be provided on the side surface of the main body case 3. Further, the lid 36 may be provided from the upper surface to the front surface of the main body case 3 as shown in FIG. 7 (c), or may be provided from the upper surface to the side surface as shown in FIG. 7 (d). Good. Second embodiment>

Next, a second embodiment of the image forming apparatus according to the present invention will be described with reference to FIGS. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

In the first embodiment, each of the housing members 2a to 2d is formed in the same shape, but in the present embodiment, each of the housing members 102a to 102d has a different shape. . As shown in FIG. 8, the guide grooves 1 17 a to 17 d of the housing members 102 a to 102 d of each of the print heads 1 a to ld of this embodiment are It includes straight grooves 81a to 81d and positioning grooves 82a to 82d. Specifically, the guide groove 1 17 d of the housing member 102 d of the print head 1 d located at the bottom is continuous with the linear groove 81 d extending in the horizontal direction and the linear groove 81 d. And a positioning groove 82d extending coaxially toward the center of the back electrode 6d. On the other hand, the guide grooves 1 17 a to 1 17 c of the other print heads 1 a to 1 c have a straight groove 8 extending in the horizontal direction. 1a to 81c and positioning grooves 82a to 82c refracted from the linear grooves 81a to 81c and extending toward the center of the back electrodes 6a to 6c, respectively. I have.

As a result, each of the developing devices 5a to 5d has its own housing member 102a to 10d while their guide shafts 15 are guided by the guide grooves 1 17a to 117d. 2d inserted into the regulation The collar 14 is positioned with the back electrodes 6a to 6d abutting on it.However, the positional relationship of each carrying roller 11 with respect to the back electrodes 6a to 6d and the intermediate image belt 7 at this time. Are the same as the positional relationship of the first embodiment. In other words, the guide grooves 1 17 a to 1 17 d are located at the position where the carrying roller 11 is properly mounted (the position where the regulating collar 14 is in contact with the opposing back electrodes 6 a to 6 d. In the vicinity of (recording position), a groove parallel to the imaginary line L connecting the center of each supporting roller 11 and the center of each of the back electrodes 6a to 6d at the recording position is formed. Has a groove shape extending horizontally.

Also, in the present embodiment, each of the upper surface walls 13 2 and each of the lower surfaces 13 3 of the housing members 102 a to 102 d are horizontal, and a spring hook formed on each lower surface wall 133 is provided. The position of 121 is different from the case of the first embodiment. However, in the present embodiment, the horizontal position of the spring hook 1 2 1 is set such that the circumference of each control plate 4 locked via the extension spring 26 is the same as in the first embodiment. Have been.

Here, the operation when the developing devices 5a to 5d are mounted on the housing members 102a to 102d will be described. First, each of the developing devices 5a to 5d has a state in which the guide shaft 15 is engaged with the guide grooves 1 17a to l 17d. It is inserted into each of the housing members 102 a to 102 d. At this time, when the guide shaft 15 is engaged with the linear grooves 81a to 81d, the developing devices 5a to 5d slide horizontally. When most of the developing units 5a to 5d are inserted, the guide shaft 15 moves from the linear grooves 81a to 81d to the positioning grooves 82a to 82d. That is, when the carrying roller 11 approaches the recording position, the carrying roller 11 is guided toward the center of the back electrodes 6a to 6d in parallel with the virtual line L. Then, when the regulating collar 14 set coaxially with the carrying roller 11 abuts on the back electrodes 6a to 6d, the developing units 5a to 5d are set at the recording positions. At this time, the positional relationship of each carrying roller 11 with respect to the back electrodes 6a to 6d and the intermediate image belt 7 is the same as in the first embodiment. Further, since the carrying roller 11 is guided toward the center of the back electrodes 6a to 6d, the radial positioning and the circumferential positioning of the carrying roller 11 with respect to the back electrodes 6a to 6d are mutually performed. It has no effect. When the carrying roller 11 is set at the recording position, the center line of the developing devices 5a to 5d (the line in the longitudinal direction of the developing devices 5a to 5d, ) And the virtual line L, and the angular position of the toner passage hole array 24 with respect to the center line of the developing devices 5a to 5d are different for each of the developing devices 5a to 5d. However, the positional relationship between the imaginary line L and the toner passage hole array 24 (that is, the mutual positional relationship of the carrying roller 11, the intermediate image belt 7, the back electrodes 6a to 6d, and the toner passage hole array 24) ) Is the same in each of the developing devices 5a to 5d. Therefore, there is no difference in the recording characteristics among the developing units 5a to 5d.

According to this embodiment, each of the housing members 10 2 a to: I 0 2 d guide grooves 1 17 a to: I 17 d have different shapes, and these guide grooves 1 17 a to l On the left end side where the control board 4 is mounted, 17 d is shaped according to the angle posture of each of the opposing back electrodes 6 a to 6 d and the intermediate image pelt 7, so any print head 1 a to ld Also, the same positional relationship as in the first embodiment can be realized. Therefore, in addition to all the effects of the first embodiment, the following new effects can be realized.

That is, first, since the inserting and removing directions of the developing units 5a to 5d are parallel and horizontal to each other, the user can insert and remove the developing units 5a to 5d only by operating from the front of the main body. The developing units 5a to 5d can be attached and detached very easily.

Second, the size of the apparatus can be reduced by reducing the dead space between the developing devices 5a to 5d and the opening area due to the parallel insertion and removal directions of the developing devices 5a to 5d. Can be planned. As shown in FIGS. 8 and 1, the height H 1 of the apparatus according to the second embodiment is smaller than the height H 0 of the apparatus according to the first embodiment, and the space between the developing units 5 a to 5 d and The height of the opening for removing the developing device is reduced by the reduced amount.

In the guide grooves 1 17 a to 1 17 d according to the present embodiment, the positioning grooves 82 a to 82 d were refracted from the linear grooves 81 a to 81 d, but the back electrode 6 a As long as the positional relationship between ~ 6d, the intermediate image belt 7, the control plate 4 and the carrying roller 11 is the same in all the print heads 1a ~ 1d, the positioning grooves 8 2a ~ 8 2d should be linear grooves. It may be provided on the same straight line as 81a to 81d. In other words, linear grooves 8 1 a to 8 1 d and positioning grooves 8 2 a to 8 2 d May be formed so as to extend on the same straight line.

Next, a third embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. 11 and FIG. In the following, the same components as those in the first and second embodiments will be denoted by the same reference numerals, and the description thereof will be omitted. Only the differences will be described. In FIG. 11, reference numerals 234a to 234d denote printhead holders, and these printhead keeper units 234a to 234d are housings according to the second embodiment. The members 102a to 102d are formed in the same shape as the left end. The print head holding portions 2 3 4 a to 2 3 4 d are positioned at the left end of the container 2 09 of the developing devices 2 0 5 a to 2 0 5 d with respect to the support port 11. It is fixed in the state, and is detached and replaced as a unit with the developing devices 205a to 205d. In addition, the print head holding portions 234a to 234d are provided with a fixed portion 219 and a stay portion 220. On the lower surface of the container 209 for accommodating the developing devices 205a to 205d, a spring hook portion 221 is formed. The control plate 4 is suspended between the fixed portion 2 19 and the spring hook portion 2 21 at the same position and the same angle as in the second embodiment via a stay portion 220.

Reference numeral 202 denotes a main housing member, and the back electrodes 6 a to 6 d are rotatably positioned and held, and guide walls 2 17 a to 2 d similar to those of the second embodiment are formed in both wall portions. 17 d is formed.

Reference numerals 235a to 235d (see FIG. 12) denote notches for preventing erroneous insertion of the developing devices 205a to 205d. The notch portions 2 3 5 a to 2 3 4 d are formed on the inner side wall of the main housing member 202 according to the shape of the tip of each print head holding portion 2 3 4 a to 2 3 4 d. Is formed. These notch portions 235a to 235 have different shapes or dimensions. Therefore, when the developing devices 205a to 205d are inserted into the wrong guide grooves of the main housing member 202, the print head holding portions 234a to 234d are The developing devices 205a to 205d cannot be inserted to the respective recording positions because they come into contact with the notch portions 235a to 235d. As a result, erroneous insertion of the developing units 205a to 205d Therefore, it is possible to prevent such a problem that the developers 8 a to 8 d of different colors adhere to the control plate 4.

According to the present embodiment, the head holders 2 3 4 having different shapes according to the angular posture of the back electrodes 6 a to 6 d of the print heads 1 a to 1 d and the intermediate image belt 7. a to 234 d are fixed to the tips of the developing devices 205 to 205 d, respectively, so that the control plate 4 is attached to the head holder 2 3 4 a to 2 3 4 In a configuration in which it is mounted on and integrated with the developing devices 205a to 205d via d, all the effects of the first and second embodiments can be obtained.

In addition, the main housing member 202 is provided with notches 235a to 235d having different shapes or dimensions according to the respective printhead holders 234a to 234d. Therefore, it is possible to prevent erroneous insertion when the developer unit 205 a to 205 d is inserted into the wrong guide groove 217 a to 217 d of the main housing member 202. it can. The shapes or dimensions of the guide shafts 15 of the print heads la to ld are made different from each other, and the guide grooves 217a to 217d are adjusted to the shapes or dimensions of the guide axes. Also, the erroneous insertion of the developing devices 205a to 205d can be prevented.

In addition, the main housing member 202 directly positions and holds both the back electrodes 6a to 6d and the support roller 11, so that the positional accuracy of both can be improved.

As shown in FIGS. 13 to 16, in the image forming apparatus according to the fourth embodiment, each of the housing members 2 a to 2 d is formed of a cylindrical container extending in the horizontal direction. For each of the housing members 2a to 2d, the developing units 5a to 5d, which respectively store the four color toners 8a to 8d of yellow, magenta, cyan and black, are arranged horizontally. It is provided so that it can be attached and detached by inserting and removing.

Since the configuration of each of the print heads 1a to 1d is basically the same, only the configuration of the print head 1b will be described in detail with reference to FIG. Detailed description of de la, lc, 1 d will be omitted. In the print head 1b according to the fourth embodiment, at least one guide shaft 15 is provided with a drive gear 37 for transmitting a rotational drive force to the carrying roller 11. The drive gear 37 is disposed on the guide shaft 15 via a one-way clutch (not shown) that rotates the carrying roller 11 only in the counterclockwise direction in FIG. A rack 38 is provided on the inner surface of the lower wall of the housing member 2b. When the developing device 5b is inserted into the housing member 2b, the driving gear 37 engages with the rack 38, and the driving force in the horizontal direction for inserting the developing device 5b is applied to the driving gear 37. The carrier roller is converted into a rotational driving force via the roller, and the carrying roller is rotated in the transport direction, that is, in the counterclockwise direction by the rotational driving force. At the right end of the housing member 2b, the developer inlet 60 is closed when the developer 5b is removed, and conversely, the developer inlet 60 when the developer 5b is inserted. There is a shirt 4 4 that opens the door.

As shown in FIGS. 13 and 14, the back electrode 6 is provided in the main body case 3, and the main housing member 2 is removably positioned and fixed to the right side of the back electrode 6.

On one side of the developer supply opening 10 of the housing member 2b, a fixing portion 19 for fixing one end of the control plate 4 is formed, and on the other side of the developer supply opening 10, A stay part 20 for projecting the other end of the control plate 4 rightward is formed to project. The stay part 20 has a substantially semicircular cross section, and the inside thereof is a toner collecting part 61 for removing unnecessary toner by removing it from the support roller 11 or the control plate 4. . On the right side of the stay part 20, a spring hook 21 is provided at an appropriate distance from the stay part 20.

The configuration of the control plate 4 is the same as in the first embodiment. One end of the control plate 4 is fixed to a fixing portion 19 of the housing member 2b with a fixing screw 25. The other end of the control plate 4 is once bent at the stay part 20, and the tip end thereof is engaged with a spring hook 21 via a tension spring 26.

A vibration plate 42 made of a metal plate extending in parallel with the toner passage hole array 24 is fixed to the inner surface of the control plate 4 at a position between the toner passage hole array 24 and the stay part 20. I have. As the vibration plate 42, for example, a stainless plate having a plate width of 5 mm and a plate thickness of 0.2 mm can be suitably used. One outer wall of both end walls 16 of housing member 2 b An ultrasonic vibration generating member 43 for generating ultrasonic vibration is fixedly supported on the outer wall portion on the back side of the main body. The output end of the ultrasonic vibration generating member 43 is screwed and fixed to one end of the diaphragm 42 in the longitudinal direction (the direction of the front and back of the paper). The vibration applied by the ultrasonic vibration generating member 43 may be any frequency as long as it removes the unnecessary toner 8 b attached to the control plate 4, but the vibration frequency is high. If too much, the toner 8b and the control plate 4 vibrate in the same manner, and it becomes impossible to effectively prevent the toner 8b from adhering or accumulating. Sine waves having a vibration frequency of 1 MHz or less are particularly preferred. For example, a sinusoidal vibration of about 2 OKHz can be suitably used. The vibration plate 42 is configured to transmit ultrasonic vibration to the control plate 4 while allowing mutual displacement between the ultrasonic vibration generation member 43 and the vibration plate 42.

Next, the operation at the time of mounting the developing devices 5a to 5d and the operation at the time of image formation will be described. First, as shown in FIG. 14, when the developing devices 5a to 5d are detached from the housing members 2a to 2d, the shirts 44 are in a closed state. At this time, each control plate 4 is in a non-contact state with other members inside the housing members 2a to 2d, that is, in an open state, and directly contacts foreign substances in the housing members 2a to 2d. In contact However, in this image forming apparatus, even when the lid 36 is open, since the shirts 44 are closed, the housing members 2a to 2d are No foreign matter enters the inside, and no foreign matter adheres to the control plate 4.

Further, since each control plate 4 is disposed at the left end of the housing members 2a to 2d, and the developing units 5a to 5d are configured to be detachably mounted by sliding horizontally, Therefore, even if foreign matter adheres to the outer surface of the shutter 44, the foreign matter does not fall freely toward the control plate 4 as the shutter 44 opens and closes.

Next, the operation when the developing units 5a to 5d are mounted will be described. As shown in FIG. 16, when the developing units 5a to 5d are mounted on the housing members 2a to 2d, the guide shafts 15 are guided and engaged with the guide grooves 17 respectively. Then, slide the developing units 5a to 5d to the left. At this time, the drive gear 37 engages with the rack 38, and the carrying roller 11 rotates counterclockwise in the figure as the developing units 5a to 5d slide leftward. . This allows Even if foreign matter adheres to the surface of the carrying roller 11 before the developing units 5a to 5d are inserted, the foreign matter is generated downstream of the carrying roller 11 in the rotation direction during recording of the carrying roller 11 as the carrying roller 11 rotates. It moves to a certain vertical portion (the portion of the carrying roller 11 that moves vertically downward, that is, the left portion in FIG. 15), and is removed by free fall. In addition, foreign matter that has not been removed by the free fall is removed by the supply roller 13 and the regulating blade 12 inside the developing units 5a to 5d. Therefore, in a state where the developing devices 5a to 5d are mounted at predetermined positions, the foreign matter once removed returns to the position of the toner passage hole 23 by the rotation of the carrying roller 11 during the recording operation. Never. Therefore, no foreign matter is caught between the supporting roller 11 and the control plate 4 to damage the control plate 4 or the insulating layer 41 of the control plate 4. Therefore, the carrying roller 11 and the image signal electrode 39 or the aperture electrode 40 of the control plate 4 are not electrically short-circuited. When the developing devices 5a to 5d are further slid leftward, the engagement between the driving gear 37 and the rack 38 is released, and the rotation of the carrying roller 11 is stopped.

Next, when the developing devices 5a to 5d are inserted to the predetermined positions, the inserted state is detected by switch means (not shown), and the ultrasonic vibration generating member 43 operates. The ultrasonic vibration of the ultrasonic vibration generating member 43 is transmitted to the control plate 4 via the diaphragm 42. Due to this vibration, foreign matter adhering around and inside the toner passage hole 23 of the control plate 4 is removed. The removed foreign matter falls vertically downward due to gravity and is collected by the toner collecting unit 61. Thereby, even if foreign matter adheres to the control plate 4 during the replacement work of the developing devices 5a to 5d, the foreign matter is reliably removed. Further, since the foreign matter is removed in the vertical downward direction, which is the downstream side in the rotation direction of the carrying roller 11 during the recording operation, the foreign matter once removed is again moved between the carrying roller 11 and the control plate 4 during the recording operation. It will not return and will not damage the control board 4 or destroy the insulating layer 41. Therefore, there is no danger of causing an electrical short.

When the developing devices 5a to 5d are further slid to the left, the regulating collar 14 comes into contact with the rear electrode 6, and the developing devices 5a to 5d are positioned at predetermined positions of the housing members 2a to 2d ( (Recording position) and mounting is completed. At this time, as shown in Fig. 13, the lid 3 6 of the main body case 3 A predetermined leftward pressing force is applied to each of the developing devices 5a to 5d by a spring member 28 provided at the recording device, and the developing devices 5a to 5d are held at the recording positions. Further, by the engagement between the guide shaft 15 and the guide groove 17, the central axis of the carrying roller 11 and the toner passage hole array 24 of the control plate 4 are positioned so as to be parallel to each other. In addition, when the regulating collar 14 abuts on the back electrode 6, the gap between the support roller 11 and the back electrode 6 is set with high precision so as to have a predetermined interval. At the same time, the carrying roller 11 comes into contact with the control plate 4 via the spacer 27, and the control plate 4 is pushed and displaced by the urging force of the tension spring 26. Thus, the gap between the support roller 11 and the control plate 4 is set with high precision by the spacer 27 so as to be a predetermined interval.

Next, the image forming operation will be described. As in the first embodiment, when a predetermined voltage is applied to a predetermined image signal electrode 39 of the control plate 4 in response to an external signal, a voltage is formed between the support roller 11 and the back electrode 6. The electric field increases, or an accelerating electric field is formed between the support roller 11 and the image signal electrode 39. Then, directly or indirectly by these electric fields, the toner 8 on the carrying roller 11 is pulled toward the back electrode 6 and flies from the carrying roller 11. The flying toner 8 passes through the toner passage hole 23 of the control plate 4 and lands on the intermediate image belt 7. On the other hand, when a voltage lower than a predetermined value is applied to the image signal electrode 39, the electric field formed between the carrying roller 11 and the back electrode 6 is weakened, and the toner 8 lands on the intermediate image belt 7. Disappears. Thus, a toner image is formed on the intermediate image belt 7 by the landed toner 8. Then, the developing units 5a to 5d for each color sequentially perform such a recording operation, so that a color image combining the yellow, magenta, cyan, and black toners 8a to 8d becomes an intermediate image. Formed on the image belt 7. At this time, by operating the ultrasonic vibration generating member 43 during the image forming operation or at predetermined intervals during the image forming operation, the ultrasonic vibration is transmitted to the control plate 4 via the diaphragm 42. However, the toner 8 attached around and inside the toner passage hole 23 is effectively removed. As a result, the control board 4 is always kept clean.

In a developer injection type device having a detachable structure, such as the image forming apparatus, foreign matter easily enters from the outside. Also, since the distance between the carrying roller 11 and the control plate 4 is extremely short, There is a great need to prevent electrical shorts due to foreign matter intrusion. Further, since the control plate 4 is urged by the tension spring 26, the control plate 4 and the carrying roller 11 are in close contact with each other via the spacer 27. Therefore, once foreign matter is caught between the control plate 4 and the carrying roller 11, it is difficult to remove the foreign matter without taking any measures. For this reason, it is preferable to remove the foreign matter before mounting the developing devices 5a to 5d, rather than removing the foreign matter later. Further, if the removed foreign matter returns to the recording section again according to the rotation of the carrying roller 11, it becomes difficult to perform good recording. For this reason, it is preferable that the foreign matter once removed does not return to the recording section. Further, even if foreign matter that cannot be completely removed before the mounting of the carrying roller 11 is collected, it is preferable that such foreign matter is dropped along with the rotation of the carrying roller 11 to be removed by itself. As described below, according to the present embodiment, the above-described problem that is particularly problematic in a developer injection type image forming apparatus can be effectively solved.

That is, according to the present embodiment, the housing members 2 a to 2 to which the developing devices 5 a to 5 d are attached and detached are provided with the shutters 44 that open and close in conjunction with the insertion and removal operations of the developing devices 5 a to 5 d. When the developing units 5a to 5d are detached from the housing members 2a to 2d, the shutter 44 is closed, so that the control plate 4 is not exposed to the outside of the apparatus. Therefore, even when the lid 36 is open, foreign matter is unlikely to enter the housing members 2 a to 2 d from outside the main body case 3, and the foreign matter adheres to the control plate 4. The fear is small.

Also, since the control plate 4 is arranged at the left end of the housing members 2a to 2d and the developing units 5a to 5d are horizontally slid, it is assumed that a Even if foreign matter adheres to the surface of 4, the foreign matter does not drop onto the control plate 4 due to gravity with the opening and closing operation of the shirt 4.

Further, since the ultrasonic vibration generating member 43 is provided, even if foreign matter adheres to the control plate 4, the foreign matter can be easily removed by applying mechanical vibration. In particular, it detects that the developing devices 5a to 5d have been inserted into the housing members 2a to 2d, and activates the ultrasonic vibration generating member 43 in accordance with this detection, thereby passing the toner through the control plate 4. The foreign matter adhering around and inside the hole 23 was removed, so the control board 4 was replaced during the replacement of the developing units 5a to 5d. Even if foreign matter adheres to the surface, the foreign matter can be removed by hand without manual intervention.

It is possible to remove foreign matter before loading Bok the developing device 5 a~5 d to the recording position, _c capable foreign matter to prevent the caught that between the control plate 4 and the carrying roller 1 1 Also, since the carrying roller 11 rotates in the transport direction (counterclockwise direction in FIG. 15) with the insertion of the developing devices 5a to 5d, before the developing devices 5a to 5d are inserted, Even if foreign matter adheres to the surface of the carrying roller 11, the foreign matter is removed in the transport direction with the rotation of the carrying roller 11. That is, the foreign matter on the carrying roller 11 is transported vertically downward, which is the downstream side in the transport direction of the carrying roller 11 during the recording operation. Among the conveyed foreign objects, those that have fallen due to gravity are collected by the collection unit 61.

On the other hand, foreign matter remaining on the carrying roller 11 without free fall is removed by the supply roller 13 and the regulating blade 12. Therefore, any foreign matter once removed from the carrying roller 11 reaches the space between the carrying roller 11 and the control plate 4 (recording portion) again as the carrying roller 11 rotates during the recording operation. Never. Therefore, when the developing devices 5a to 5d are set at predetermined positions, foreign matter is caught between the carrying roller 11 and the control plate 4 to damage the surface of the control plate 4, or to insulate the control plate 4. Nothing destroys layer 41.

Further, in the present embodiment, since the rack 38 is engaged with the lower side of the drive gear 37, the carrying roller 11 is automatically rotated in the transport direction according to the insertion of the developing devices 5a to 5d. be able to.

Further, in the present embodiment, since the carrying roller 11 and the driving gear 37 are engaged via a one-way clutch, and the carrying roller 11 rotates only in the transport direction, the developing devices 5a to 5d When the roller is pulled out from the housing members 2a to 2d rightward, the carrying roller 11 does not rotate in the counter-conveying direction (clockwise in FIG. 15), and the carrying roller 11 moves in the counter-conveying direction. It is possible to prevent toner leakage due to rotation.

Therefore, according to the present embodiment, it is possible to prevent foreign matter from adhering to the carrying roller 11 and the control plate 4 when the developing units 5 a to 5 d are replaced or the print heads 1 a to 1 d are cleaned. And even if foreign matter adheres, without human intervention Can be removed automatically. As a result, the surface of the control plate 4 or the carrying roller 11 is not damaged, and the carrying roller 11 and the image signal electrode 39 of the control plate 4 are not electrically short-circuited. When the image quality is reduced or missing dots occur, it is possible to prevent a defect in image quality, and to improve the performance and reliability of the apparatus. In this embodiment, when the developing devices 5a to 5d are mounted on the housing members 2a to 2d, the driving gear 37 engages with the rack 38, and the developing devices 5a to 5d are connected. The carrying roller 11 automatically rotates with the insertion operation to the left.However, the driving gear 37 at the position in the middle of the insertion is rotationally driven by an electric driving means. The carrying roller 11 may be rotated. With such a configuration, even when the rotational torque of the drive gear 37 is large, the developing devices 5a to 5d can be inserted into the housing members 2a to 2d with a small force.

Also, a plurality of gear trains for transmitting the reduced rotational driving force to the carrying roller 11 are provided in the developing devices 5a to 5d, and each gear constituting the gear train is sequentially engaged with the rack 38. As a result, the insertion load of the developing devices 5a to 5d may be reduced in the same manner as described above.

Further, in the present embodiment, the foreign matter is removed using the ultrasonic vibration generating member 43, but mechanical vibration may be applied to the control plate 4 by a method other than the ultrasonic vibration. For example, the tension spring 26 is gradually displaced in conjunction with the insertion of the developing devices 5a to 5d, and momentarily when the developing devices 5a to 5d are inserted to a predetermined position before the recording position. By releasing the displacement, mechanical vibration may be applied to the control plate 4. With such a configuration, a similar effect can be obtained at a low cost.

The cleaning means for removing the foreign matter is not limited to a means for applying mechanical vibration, but may be another means. For example, a device using an electric field, a device using a jet flow (air purge type), a device using a brush or the like may be used. The image forming apparatus according to the present embodiment includes four developing units 5a to 5d containing developers 8a to 8d of four colors of yellow, yellow, cyan, and black in order to form a color image. And the four control boards 4, but the present invention can of course be applied to an image forming apparatus having a single developing device and a control board and performing monochromatic recording. Industrial applicability

INDUSTRIAL APPLICABILITY As described above, the present invention is useful for an image forming apparatus that forms an image by ejecting a developer to a recording member, and is useful for, for example, a copying machine, a facsimile, and a printer.

Claims

The scope of the claims

1. a developer carrier that carries and transports the charged developer;

A back electrode disposed to face the developer carrier,

An intermediate image holding means provided between the developer carrier and the back electrode; and a plurality of developer passage holes provided between the developer carrier and the intermediate image holding means. And a signal electrode provided around each developer passage hole in the insulating base and supplied with an image signal, and the developer is provided based on the image signal. A developer passage control member for flying the developer on the carrier so as to pass through a predetermined developer passage hole and attaching the developer to the intermediate image holding means, and forming an intermediate image on the intermediate image holding means; Transfer means for transferring an intermediate image on the intermediate image holding means to a recording medium, wherein the back electrode is in contact with the intermediate image holding means so as to have a winding angle of 2 to 90 degrees. An image forming apparatus having a contact portion.

2. The image forming apparatus according to claim 1, wherein

The image forming apparatus, wherein the back electrode is formed by a columnar or cylindrical electrode extending in a direction orthogonal to a running direction of the intermediate image holding unit.

3. The image forming apparatus according to claim 2, wherein

The image forming apparatus, wherein the back electrode includes a rotatable electrode roller.

4. The image forming apparatus according to claim 1, wherein

A developer supply unit having a container for accommodating a developer and having the developer carrier attached thereto; and

A housing member for detachably mounting the developer supply unit,

The image forming apparatus, wherein the developer passage control member is attached to the housing member.

5. The image forming apparatus according to claim 4, wherein

The developer supply unit is configured such that when the developer supply unit is mounted on the housing member, the back electrode is maintained at a predetermined distance between the developer carrier and the back electrode. An image forming apparatus having a first spacer in contact with the image forming apparatus.

6. The image forming apparatus according to claim 5, wherein

The developer passage control member includes a control plate having one end fixed to the housing member and the other end connected to the housing member via a tension member,

The image forming apparatus, wherein the developer carrier is in contact with the control plate so as to press the control plate.

7. The image forming apparatus according to claim 5, wherein

The image forming apparatus, wherein the developer carrier is in contact with the control plate via a second spacer so as to press the control plate.

8. The image forming apparatus according to claim 4, wherein

The developer supply unit is provided with first engagement means,

The image forming apparatus, wherein the housing member is provided with a second engagement unit that guides insertion and removal of the developer supply unit by engaging with the first engagement unit.

9. The image forming apparatus according to claim 8, wherein

The first engagement means comprises a projection or a rod-like member projecting from the developer supply unit,

The second engagement means is an image-type image comprising guide means for guiding the protrusion or the rod-shaped member.

10. The image forming apparatus according to claim 8, wherein

The image forming apparatus, wherein the developer supply unit is guided so that the developer carrier moves toward the center of the back electrode.

11. The image forming apparatus according to claim 9, wherein

The image forming apparatus includes: an insertion portion extending in a predetermined insertion direction; and a positioning portion that continuously or refracts from the insertion portion and guides the developer carrier to a predetermined recording position. .

12. The image forming apparatus according to claim 11, wherein

The image forming apparatus, wherein the insertion section and the positioning section are disposed so as to extend on the same straight line.

13. The image forming apparatus according to claim 1, wherein a plurality of recording units each including the developer carrier, the developer passage control member, and the back electrode are provided. With

The image forming apparatus, wherein the intermediate image holding means is provided so as to sequentially travel between a developer passage control member of each of the recording units and a back electrode.

14. A developer carrier that carries and transports the charged developer;

A back electrode disposed to face the developer carrier,

An insulating substrate provided between the developer carrier and the back electrode and having a plurality of developer passage holes formed therein; and an insulating substrate disposed around each of the developer passage holes in the insulating substrate. And a signal electrode to which an image signal is supplied. The developer on the developer carrier is caused to pass through a predetermined developer passage hole and fly toward the back electrode based on the image signal. With the developer passage control member A plurality of recording units including at least a first, a second and a third recording unit comprising:

In order to generate an intermediate image by receiving the developer from the developer passage control member of each of the recording sections, it is arranged so as to sequentially travel between the developer passage control member of each of the recording sections and the back electrode. Intermediate image holding means,

Transfer means for transferring the intermediate image on the intermediate image holding means to a recording medium, the image forming apparatus comprising:

At least each of the back electrodes of the first, second, and third recording units has a contact portion that comes into contact with the intermediate image holding unit, while the contact portion of the rear electrode of the second recording unit has An image forming apparatus disposed so as to protrude toward the intermediate image holding belt side from an imaginary line connecting a contact portion of the back electrode of the first recording unit and a contact portion of the back electrode of the third recording unit.

15. A developer carrier that carries and transports the charged developer;

A back electrode disposed to face the developer carrier,

An insulating substrate provided between the developer carrier and the back electrode and having a plurality of developer passage holes formed therein; and an insulating substrate disposed around each of the developer passage holes in the insulating substrate. And a signal electrode to which an image signal is supplied. The developer on the developer carrier is caused to pass through a predetermined developer passage hole and fly toward the back electrode based on the image signal. With the developer passage control member

A plurality of recording units including at least first and second recording units comprising:

A guide member for guiding the intermediate image holding unit to the first recording unit so that the intermediate image holding unit travels from the first recording unit toward the second recording unit;

At least the guide member and the back electrodes of the first and second recording sections are located at the intermediate position. Each of the contact portions contacting the image holding means is provided, while the contact portion of the back electrode of the first recording unit is in contact with the contact portion of the guide member and the contact portion of the back electrode of the second recording unit. The image forming apparatus is disposed so as to protrude more toward the intermediate image holding belt side than a virtual line connecting.

16. The image forming apparatus according to claim 14 or 15, wherein

An image forming apparatus, wherein a mutual positional relationship among a developer carrying member, a developer passage control member, an intermediate image holding unit, and a back electrode of each recording unit is the same among a plurality of recording units.

17. The image forming apparatus according to claim 16, wherein

Each of the recording units has a container for accommodating a developer and has a developer supply unit to which the developer carrier is attached,

An image forming apparatus in which the direction of insertion and removal of the developer supply unit is different for each developer supply unit.

18. The image forming apparatus according to claim 16, wherein

Each of the recording sections includes a developer supply unit having a storage container for storing a developer and having the developer carrying member attached thereto, and a housing member to which each of the developer supply units is detachably mounted. ,

Each of the developer supply units is provided with first engagement means,

A developer passage control member is attached to each of the housing members, and a second engagement means is provided for guiding insertion and removal of the developer supply unit by engaging with the first engagement means. And

The developer is supplied such that the angle of inclination of the developer supply unit mounted on the upper side of the apparatus main body in the insertion / removal direction with respect to the horizontal plane is greater than that of the developer supply unit mounted on the lower side of the apparatus main body. An image forming apparatus in which supply units are arranged non-parallel to each other.

19. The image forming apparatus according to claim 18, wherein The first engagement means comprises a projection or a rod-like member projecting from the developer supply unit,

20. The image forming apparatus according to claim 16, wherein

An image forming apparatus in which insertion and removal directions when the developer supply unit is attached and detached are parallel to each other.

21. The image forming apparatus according to claim 16, wherein

Each of the developer supply units is provided with a protrusion or a rod-like member projecting from the developer supply unit,

A developer passage control member is attached to each of the housing members, and an insertion portion extending in a predetermined insertion direction is provided. The developer carrier is continuously or refracted from the insertion portion to place the developer carrier at a predetermined recording position. While the guide means for the projection or the rod-shaped member including a positioning portion for guiding the

An image forming apparatus wherein the insertion portions of the housing member of the recording unit are formed in parallel with each other.

22. The image forming apparatus according to claim 21, wherein

23. The image forming apparatus according to claim 16, wherein

Each of the recording units includes a developer supply unit having a storage container for storing a developer and having the developer carrying member attached thereto; and a developer supply unit provided in the developer supply unit; A supporter for supporting the developer supply unit so as to cover the front end side of the developer carrier,

Each of the developer supply units is provided with an engagement means comprising a projection or a rod-like member protruding from the developer supply unit.

A housing member formed with a plurality of guide means for guiding the engagement means of each of the developer supply units;

Each guide means of the housing member has an insertion portion extending in a predetermined insertion direction, and a positioning portion connected or bent from the insertion portion to guide each of the developer carriers to a predetermined recording position. Image forming apparatus.

24. The image forming apparatus according to any one of claims 21 to 23, wherein the insertion unit disconnects each of the developer supply units when each of the developer supply units is mounted. An image forming apparatus formed so as to be guided in a horizontal direction, a diagonally downward direction, or a downward direction.

25. The image forming apparatus according to any one of claims 21 to 23, wherein the insertion section includes a horizontal guide section extending in a horizontal direction.

26. The image forming apparatus according to any one of claims 1 to 23, wherein the developer supply units of the recording unit are formed in the same shape.

27. The image forming apparatus according to any one of claims 17 to 23, wherein a developer carrier of each of the developer supply units, a developer passage control member, an intermediate image holding unit, and a back electrode are provided. The mutual positional relationship is the same among multiple developer supply units. While

An image forming apparatus in which the positional relationship of the storage container with respect to the back electrode and the intermediate image holding unit differs for each developer supply unit.

28. The image forming apparatus according to claim 27, wherein

While the shape and dimensions of the container for the developer supply unit are the same among a plurality of developer supply units,

An image forming apparatus, wherein a positional relationship between a virtual line connecting a center of a developer carrier and a center of a developer passage hole of a developer passage control member and the storage container is different for each developer supply unit.

29. The image forming apparatus according to any one of claims 18, 19, and 21 to 23,

An image forming apparatus in which the developer supply unit of each recording section is different in shape or size from the developer supply unit of another recording section so that the developer supply unit cannot be inserted into or removed from a housing member of another recording section.

30. The image forming apparatus according to claim 18, wherein

The first engaging means of the developer supply unit of each of the recording sections does not engage with the second engaging means of the other recording section, so that the first engagement section of the developer supply unit of the other recording section does not engage with the first engaging section. An image forming apparatus having a different shape or size from the means.

31. The image forming apparatus according to claim 23, wherein

The developer supply unit of the other recording unit is engaged with the guide unit that guides the engagement unit of the developer unit of the other recording unit. An image forming apparatus having a different shape or size from the engaging means.

32. a developer supply unit having a storage container for storing the developer, and a developer carrying body for carrying and transporting the developer in the storage container; A back electrode disposed to face the developer carrier,

An image receiving member disposed between the developer carrier and the back electrode,

An insulating substrate provided between the developer carrier and the image receiving member and having a plurality of developer passage holes formed therein; and an insulating substrate disposed around each developer passage hole of the insulating substrate. And a signal electrode to which an image signal is supplied, and based on the image signal, the developer on the developer carrier is caused to fly so as to pass through a predetermined developer passage hole, and is applied to the image receiving body. And a developer passage control member to be attached.

The developer supply unit is formed detachably with respect to the apparatus main body,

When the developer supply unit is mounted on the apparatus main body, a portion of the developer carrier that faces the developer passage hole of the developer passage control member vertically or substantially vertically faces the developer. An image forming apparatus formed to be conveyed in a downward direction.

33. a developer supply unit having a housing container for housing the developer and a developer carrier for carrying and transporting the developer in the housing container;

A back electrode disposed to face the developer carrier,

An insulating substrate provided between the developer carrier and the image receiving member and having a plurality of developer passage holes formed therein; and an insulation substrate disposed around each developer passage hole of the insulating substrate. And a signal electrode to which an image signal is supplied, and the developer on the developer carrier is caused to fly so as to pass through a predetermined developer passage hole on the basis of the image signal so as to be applied to the image receiving body. And a developer passage control member to be attached.

An image forming apparatus, wherein the developer supply unit is inserted and removed in a horizontal direction or a substantially horizontal direction with respect to the apparatus main body.

34. a developer supply unit having a housing container for housing the developer and a developer carrier for carrying the developer in the housing container while carrying the developer;

A back electrode disposed to face the developer carrier, An image receiving member disposed between the developer carrier and the back electrode,

An insulating substrate provided between the developer carrier and the image receiving member and having a plurality of developer passage holes formed therein; and an insulation substrate disposed around each developer passage hole of the insulating substrate. And a signal electrode to which an image signal is supplied, and the developer on the developer carrier is caused to fly so as to pass through a predetermined developer passage hole on the basis of the image signal so as to be applied to the image receiving body. A developer passage control member to be attached;

An apparatus main body that is provided with a unit inlet for inserting the developer supply unit, and that supports the developer supply unit in a freely insertable and removable manner;

The unit inlet is opened and closed in conjunction with the insertion and removal of the developer supply unit so that the unit inlet of the apparatus main body is closed when the developer supply unit is detached from the apparatus main body. Shutter means

An image forming apparatus comprising:

35. A developer supply unit having a storage container for storing the developer and a developer carrying body for carrying and transporting the developer in the storage container, the developer supply unit being detachably formed in the apparatus main body;

A back electrode disposed to face the developer carrier,

A removing means for removing foreign substances adhering to the developer passage control member when the developer supply unit is not mounted on the apparatus main body or when the developer supply unit is mounted on the apparatus main body; An image forming apparatus comprising: a cleaning unit that performs a cleaning operation.

36. The image forming apparatus according to claim 35, wherein

The image forming apparatus, wherein the cleaning unit includes a vibration unit that applies mechanical vibration to the developer passage control member.

37. A developer supply unit having a storage container for storing the developer and a developer carrying member for carrying and transporting the developer in the storage container, the developer supply unit being detachably formed in the apparatus main body;

A back electrode disposed to face the developer carrier,

An insulating substrate disposed between the developer carrier and the image receiving member and having a plurality of developer passage holes formed therein; and an insulating substrate disposed around each developer passage hole of the insulating substrate. And a signal electrode to which an image signal is supplied. Based on the image signal, the developer on the developer carrier is caused to fly so as to pass through a predetermined developer passage hole and adhere to the image receiver. A developer passage control member for causing

An image forming apparatus, wherein the developer supply unit is formed so as to carry a transporting motion to the developer carrier when the developer supply unit is mounted on the apparatus body.

38. The image forming apparatus according to claim 32, 34, 35, or 37, wherein the developer supply unit is formed so as to be freely inserted into and removed from the apparatus main body in a horizontal direction or a substantially horizontal direction. Image forming apparatus.

39. The image forming apparatus according to claim 32, 33, 35, or 37, wherein a unit entrance for inserting the developer supply unit is formed in the apparatus main body,

When the developer supply unit is detached from the apparatus main body, the unit is inserted in and out of the developer supply unit so as to close the unit insertion opening of the apparatus main body. An image forming apparatus having a shirt opening and closing means for opening and closing an entrance.

40. The image forming apparatus according to claim 32, 33, 34, or 37, wherein the developer supply unit does not include the developer supply unit attached to the apparatus main body. Cleaning means is provided for executing a cleaning operation for removing foreign substances adhering to the developer passage control member, at the time of or at the time of mounting the developer supply unit on the apparatus main body. Image forming apparatus.

41. The image forming apparatus according to claim 40, wherein

42. The image forming apparatus according to claim 35, wherein

The image forming apparatus according to claim 1, wherein the apparatus main body includes a recovery unit configured to recover the developer removed from the developer passage control member.

43. The image forming apparatus according to claim 32, 33, 34, or 35, wherein the developer supply unit is transported to the developer carrier as the developer supply unit is mounted on the apparatus main body. An image forming apparatus that is formed to perform exercise.

44. The image forming apparatus according to claim 36, wherein

The vibration means,

An ultrasonic vibration generator that generates ultrasonic vibration,

The developer passage control member is fixed to the side of the developer passage hole of the developer passage control member so as to extend in the direction of arrangement of the developer passage holes of the developer passage control member. A vibrator having one end connected to the ultrasonic vibration generator so as to transmit the vibration to the developer passage control member; An image forming apparatus comprising:

45. The image forming apparatus according to claim 37, wherein

An image forming apparatus comprising: an image forming unit configured to prevent the developer carrier from performing a transport movement in a direction opposite to a developer transport direction when the developer supply unit is attached to or detached from the apparatus main body.

46. The image forming apparatus according to claim 37, wherein

The developer carrier is constituted by a carrier roller,

The carrier roller is provided with a rotating gear unit that rotates together with the carrier roller. The apparatus main body includes the rotation unit that rotates the carrier roller in a developer conveying direction with the mounting of the developer supply unit. An image forming apparatus provided with rack means for engaging with gear means.

47. The image forming apparatus according to claim 46, wherein

The carrying roller is provided in the container such that a part of the roller is exposed to the outside of the container, and a portion of the developer passage control member facing the developer passage hole directs the developer vertically downward. Formed to carry,

The apparatus main body is provided with a housing member formed so that the container can be inserted and removed in the horizontal direction.

The rotating gear means is disposed coaxially with the carrying roller,

The image forming apparatus, wherein the rack means is provided on an inner lower surface of the housing member.

48. The image forming apparatus according to claim 46, wherein

The image forming apparatus according to claim 1, wherein the rotating gear unit is formed by a reduction gear that reduces a rotational driving force generated by engagement with the rack unit and transmits the rotation driving force to the support roller.