JP2005222088A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color printer realizing the prevention of faulty conveyance and faulty ejection of paper and realizing miniaturization by preventing dead space from being formed between an intermediate transfer belt and a paper ejection part, and made excellent in the maintainability of internal component parts/devices and units. <P>SOLUTION: The paper P is conveyed to pass through a secondary transfer position and a fixing position in a fixing device 30 in an upward direction, and at least a part of the paper receiving surface 42 of an ejection stack part 40 is formed as an inclined surface which is inclined downward as it comes close to an ejection port 41 side and whose lowermost end is lower than the ejection port 41, and the intermediate transfer belt 10 is stretched and laid so that its upper stretched and laid part may be inclined and extended along the paper receiving surface 42 of the stack part 40. Then, photoreceptor drums 1A and 1B are arranged to be opposed to the lower stretched and laid part of the belt 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image forming apparatus such as a copying machine, a printer, and a FAX, and a transport unit, an intermediate transfer unit, and a process cartridge used in the apparatus. More specifically, an image forming apparatus that transfers images on a plurality of image carriers to an intermediate transfer body and collectively transfers the images on the intermediate transfer body to a recording medium, and a transport unit, an intermediate transfer unit, and a process cartridge used in the apparatus It is about.

2. Description of the Related Art Conventionally, a tandem type color image forming apparatus is known in which four photosensitive drums as image bearing members are arranged side by side along a stretched portion of an endless belt-shaped intermediate transfer member that is stretched in the horizontal direction ( For example, see Patent Document 1). In this image forming apparatus, toner images of different colors are formed on four photosensitive drums, and the toner images on the photosensitive drums are primarily transferred so as to be superimposed on the intermediate transfer member. Then, the toner images superimposed on the intermediate transfer member are collectively transferred onto a sheet as a recording medium. The sheet that has passed the secondary transfer position is discharged onto the sheet receiving surface (recording medium receiving surface) through the discharge port of the discharge unit positioned above the intermediate transfer body after the image is fixed by the fixing unit. .
Further, the sheet receiving surface in the discharge portion (see FIG. 13) of the image forming apparatus described in Patent Document 1 is formed as a horizontal flat portion at a portion far from the discharge port. And the part close | similar to a discharge port is formed with the convex curve part which drew the curve gradually and became low as it approached the discharge port. The toner cartridges for the respective colors are arranged in parallel in the horizontal direction below the horizontal plane portion of the paper receiving surface, and further, the support member is arranged below the toner cartridges so that the upper stretch portion extends in the horizontal direction. A stretched intermediate transfer member is arranged.

JP 2001-117384 A JP 2001-209232 A

  However, in an image forming apparatus having a discharge unit as described in Patent Document 1, when an image is formed on a large and thick paper such as thick paper or an OHP sheet and then discharged to the discharge unit, the following is performed. There was a risk of poor discharge. When a sheet such as a thick sheet or an OHP sheet is used, the trailing end PT of the sheet P extends along the inclined curve portion 401 a of the recording medium receiving surface 401 depending on the strength (rigidity) of the sheet P, as shown in FIG. It is in a state where it is lifted upward without bending. Even when the paper P is curled in a direction perpendicular to the paper discharge direction, the rear end portion PT of the paper P is lifted upward without being bent along the inclined curve portion 401 a of the paper receiving surface 401. Thus, when the rear end portion PT of the paper P discharged onto the paper receiving surface 401 of the discharge portion 400 is lifted upward, it will collide with the leading end portion of the subsequent paper discharged to the discharge portion thereafter. For this reason, there is a risk that paper discharge failure may occur.

On the other hand, the conventional image forming apparatus includes a plurality of image forming means such as a photosensitive drum and a charging device associated therewith, and an endless belt-like intermediate transfer member stretched around a plurality of support members. As a result, the entire apparatus tends to be enlarged. Therefore, in particular, it has been desired to reduce the size of the device by minimizing dead space in the device.
However, in the image forming apparatus including the plurality of photosensitive drums and the intermediate transfer body, if the internal components, the apparatus, and the unit are disposed so as to eliminate the dead space in the apparatus main body in order to reduce the size of the apparatus, the photosensitive body There has been a problem that the maintainability may be deteriorated at the expense of the exchangeability of the internal components / devices and units constituting the image forming means including the drum and the intermediate transfer member. For example, in Patent Document 2, three color toner photosensitive drums are opposed to an upper stretch portion of an intermediate transfer member (intermediate transfer belt), and a black photosensitive drum is opposed to a lower stretch portion. An image forming apparatus is described. In this image forming apparatus, when the central intermediate transfer member is to be replaced, the upper color toner photosensitive drum and its associated components are moved upward and retracted, and the lower black photosensitive drum and Since it is necessary to move the components accompanying it downward and retract, the maintainability is poor.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to prevent recording medium conveyance failure and ejection failure and to save space by reducing dead space in the device. An object of the present invention is to provide an image forming apparatus that can be reduced in size and has excellent maintainability of internal components, apparatuses, and units, and a transport unit, an intermediate transfer unit, and a process cartridge used in the apparatus.

In order to achieve the above object, the invention of claim 1 is directed to a plurality of image carriers, image forming means for forming images of different colors on each image carrier, and a primary facing each image carrier. An endless belt-like intermediate transfer member that is stretched and driven by a plurality of support members so as to pass the transfer position, and an image of each color formed on each image carrier is superimposed on the intermediate transfer member and transferred. A primary transfer unit that performs a batch transfer of an image on the intermediate transfer member to a recording medium at a secondary transfer position located on one end side in the horizontal direction of the intermediate transfer member, A fixing unit provided above the secondary transfer position so as to fix the image on the recording medium that has passed the secondary transfer position, a secondary transfer position in the secondary transfer unit, and a fixing position in the fixing unit; Conveying the recording medium so that it passes upward An image forming apparatus comprising: a step; and a discharge unit having a recording medium receiving surface positioned above the intermediate transfer member and a discharge port for discharging the recording medium that has passed through the fixing unit onto the recording medium receiving surface. And at least a part of the recording medium receiving surface of the discharge portion is inclined downward as it approaches the discharge port side, and its lowermost end is formed with an inclined surface lower than the discharge port. The intermediate transfer member is stretched so that the body extends in an inclined manner along the inclined surface of the discharge portion, and the plurality of image carriers are disposed so as to face the lower stretch portion of the intermediate transfer member. The body is arranged.
In the image forming apparatus according to claim 1, at least a part of the recording medium receiving surface of the discharge portion is inclined downward as approaching the discharge port side, and the lowermost end is an inclined surface lower than the discharge port. Therefore, the recording medium discharged from the discharge port can be received on the recording medium receiving surface having the inclined surface in a state where the rear end is inclined so as to be lower than the discharge port. Accordingly, it is possible to discharge a plurality of recording media in a state in which the rear end of the recording medium received by the recording medium receiving surface does not easily collide with the leading end of the subsequent recording medium continuously discharged from the discharge port.
Here, if the intermediate transfer member positioned below the recording medium receiving surface having the inclined surface of the discharge portion is stretched in the horizontal direction, the space between the inclined surface of the recording medium receiving surface and the intermediate transfer member Becomes dead space. Therefore, the intermediate transfer member is stretched so that the intermediate transfer member extends while being inclined along the inclined surface of the recording medium receiving surface of the discharge portion. Accordingly, the intermediate transfer member and the inclined surface of the recording medium receiving surface of the discharge unit are brought close to each other so that no dead space is generated between them.
A plurality of image carriers are arranged so as to face the lower stretched portion of the intermediate transfer member. As a result, a plurality of image forming units for the respective image carriers can be collectively arranged below the lower stretch portion of the intermediate transfer member, and the respective image forming units are disposed at relatively close positions. Become. Therefore, unlike the case where the image forming means is provided separately on the upper and lower stretched portions of the intermediate transfer member, some of the components constituting each image forming means can be shared. Thus, further space saving inside the apparatus can be achieved. In addition, since a plurality of image forming means for each image carrier can be arranged together below the lower stretch portion of the intermediate transfer member, internal components such as the intermediate transfer member and the image carrier or intermediate transfer When the unit such as the unit or the process cartridge is replaced, it is only necessary to retract each image carrier so as to separate only the lower stretch portion of the intermediate transfer member. Therefore, it is easier to attach and detach internal components and units than when a plurality of image carriers are arranged so as to face both the upper and lower stretched portions of the intermediate transfer member.
According to a second aspect of the present invention, in the image forming apparatus of the first aspect, the image forming means is configured to form images of a plurality of different colors on at least one of the image carriers. It is a feature.
According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the conveyance unit supports and conveys the recording medium along a conveyance path that passes through the secondary transfer position and goes to the fixing position. Thus, it is configured using a conveyor belt member stretched by a plurality of support members.
According to a fourth aspect of the present invention, in the image forming apparatus of the third aspect, the conveying belt member is formed of a heat resistant material.
According to a fifth aspect of the present invention, in the image forming apparatus according to the third or fourth aspect, the conveying belt member and a part of the conveying path forming member constituting the conveying means are integrated so as to open the conveying path. A movable moving unit is provided.
According to a sixth aspect of the present invention, in the image forming apparatus according to the fifth aspect, the moving unit conveys the recording medium that has passed through the fixing means so as to pass through the secondary transfer position again with the front and back surfaces reversed. The image forming apparatus includes a conveying unit for forming a double-sided image.
According to a seventh aspect of the present invention, in the image forming apparatus according to the fifth or sixth aspect, when the moving unit is moved so as to open the conveying path, the conveying belt member and a part of the conveying path forming member are The transport unit integrally configured to include the detachable unit is detachable from the moving unit.
According to an eighth aspect of the present invention, in the image forming apparatus according to the first or second aspect, an image of each color to be supplied to the image forming means is formed between the intermediate transfer member and the recording medium receiving surface of the discharge section. A plurality of toner storage portions for storing different toners, and a heat shield for blocking heat transfer from the fixing means to the toner storage portion between the toner storage portion and the fixing means. Means are provided.
According to a ninth aspect of the present invention, in the image forming apparatus according to the eighth aspect, a heat insulating member is provided as the heat shielding means.
According to a tenth aspect of the present invention, in the image forming apparatus according to the eighth or ninth aspect, a ventilating unit that circulates air between the toner containing portion and the fixing unit is provided as the heat shielding unit. Is.
According to an eleventh aspect of the present invention, in the image forming apparatus according to the first or second aspect, an image of each color to be supplied to the image forming means is formed between the intermediate transfer member and the recording medium receiving surface of the discharge portion. A plurality of toner storage portions for storing different toners are provided side by side, and the toner storage portions are formed of a heat insulating material.
According to a twelfth aspect of the present invention, in the image forming apparatus of the first or second aspect, an image of each color to be supplied to the image forming means is formed between the intermediate transfer member and the recording medium receiving surface of the discharge section. Are arranged side by side, and when the intermediate transfer member is moved away from the plurality of image carriers, the toner storage unit and the intermediate transfer member do not interfere with each other. As described above, a space is provided between the toner container and the intermediate transfer member.
According to a thirteenth aspect of the present invention, in the image forming apparatus according to any one of the eighth to twelfth aspects, the toner container is detachable from the main body of the image forming apparatus.
According to a fourteenth aspect of the present invention, in the image forming apparatus according to any one of the first to thirteenth aspects, an intermediate transfer unit integrally configured to include the intermediate transfer member and its supporting member is separated from the image carrier. In this state, the image forming apparatus can be attached to and detached from the image forming apparatus main body.
According to a fifteenth aspect of the present invention, in the image forming apparatus according to any one of the first to fourteenth aspects, the image carrier, a charging device constituting the image forming means, a developing device, and a cleaning for cleaning the surface of the image carrier. A process cartridge integrally configured to include at least one of the apparatuses is detachable from the main body of the image forming apparatus.
According to a sixteenth aspect of the present invention, in the image forming apparatus according to any one of the first to fourteenth aspects, the process cartridge integrally configured to include at least the charging device and the developing device constituting the image forming unit is the image carrier. It is characterized in that it can be attached to and detached from the image forming apparatus main body independently of the image carrier in a state of being separated from the body.
According to a seventeenth aspect of the present invention, in the image forming apparatus according to any one of the first to sixteenth aspects, the image among the constituent elements constituting the intermediate transfer member and the image forming unit with respect to the plurality of image carriers. The intermediate transfer member and the opposing component are configured to be movable so as to be separated from the opposing component facing the carrier, and the intermediate transfer member and the opposing component are separated from the image carrier. In this state, only the image carrier is detachable from the apparatus main body.
According to an eighteenth aspect of the present invention, in the image forming apparatus according to any one of the first to thirteenth aspects, the process cartridge integrally configured to include the image carrier, the intermediate transfer member, and a support member thereof is an image. It is characterized in that it can be attached to and detached from the forming apparatus main body.
According to a nineteenth aspect of the present invention, in the image forming apparatus according to the fifteenth, sixteenth or eighteenth aspect, the process cartridge is integrally provided for all or a part of the plurality of image carriers. It is.

According to a twentieth aspect of the present invention, in the image forming apparatus according to the first or second aspect, the moving mechanism that moves downward the opposing constituent elements facing the plurality of image carriers among the constituent elements constituting the image forming means. And moving the opposing component so that the opposing component and the moving mechanism do not interfere with each other when the opposing component is moved downward and separated from the plurality of image carriers. This is characterized in that a space is provided between the mechanism portion.
According to a twenty-first aspect of the present invention, in the image forming apparatus of the twentieth aspect, the moving mechanism portion has a contact surface with which a lower end portion of a rail member supporting the opposed component contacts from above and the rail The cam member is movable in the direction intersecting the abutting direction of the lower end of the member, and the opposing component takes an image forming position and a separated position separated from the image carrier by the movement of the cam member. As is obtained, the contact surface of the cam member is formed.
According to a twenty-second aspect of the present invention, in the image forming apparatus according to the twenty-first aspect, the intermediate transfer is performed in accordance with the movement of the cam member that moves the opposed structural element from the image forming position to the separated position. The body and its supporting member are configured to move from the image forming position to a separated position separated from the image carrier.
According to a twenty-third aspect of the present invention, in the image forming apparatus of the twenty-second aspect, the moving mechanism is engaged with a cam portion provided at one end and the cam member so as to rotate in conjunction with the cam member. A pivotable lever member having an engaging portion, and the cam portion of the lever member moves the intermediate transfer member and the support member away from the image forming position with the rotation of the lever member. It is characterized by being formed to move between positions.
According to a twenty-fourth aspect of the present invention, in the image forming apparatus according to the twenty-third aspect, the lever member is provided with a knob for an operator to operate the lever member to rotate.
According to a twenty-fifth aspect of the invention, in the image forming apparatus of the twenty-third aspect, the cam portion of the lever member is formed so as to be operable by an operator so as to rotate the lever member. .
According to a twenty-sixth aspect of the present invention, in the image forming apparatus according to the twenty-third aspect, the conveyance unit supports and conveys the recording medium along a conveyance path passing through the secondary transfer position and toward the fixing position. The conveyor belt member stretched by a plurality of support members is used, and the conveyor belt member and a part of the conveyor path forming member constituting the conveyor means are integrated so as to open the conveyor path. A movable moving unit is provided, and the lever member is configured to rotate in conjunction with the movement of the moving unit to open the transport path.
According to a twenty-seventh aspect of the present invention, in the image forming apparatus according to any one of the twenty-second to twenty-sixth aspects, a case member to which the opposing component is attached, and a direction fixed to the case member and in the direction of the rotation axis of the image carrier. And a movable rail member that is movable.

According to a twenty-eighth aspect of the present invention, there is provided a conveyance unit in the image forming apparatus according to the seventh aspect, wherein the conveyance unit includes the conveyance belt member and a part of the other conveyance member, and opens the conveyance path. It can be attached to and detached from the moved moving unit.
According to a twenty-ninth aspect of the present invention, in the conveyance unit according to the twenty-eighth aspect, the conveyance member includes one roller of a pair of registration rollers as a part of the conveyance member, and a cleaning unit that cleans the roller. is there.
A thirty-third aspect of the invention is characterized in that, in the conveyance unit of the twenty-eighth aspect, an accommodation portion is provided for accommodating the foreign matter removed by the cleaning means.
According to a thirty-first aspect of the present invention, there is provided an intermediate transfer unit in the image forming apparatus according to the fourteenth aspect, wherein the intermediate transfer unit and the supporting member are integrally configured so as to be separated from the image carrier. It is characterized in that it can be attached to and detached from the forming apparatus main body.
According to a thirty-second aspect of the present invention, there is provided a process cartridge in the image forming apparatus according to the fifteenth aspect, wherein the image carrier, a charging device constituting the image forming means, a developing device, and a cleaning for cleaning the surface of the image carrier. The image forming apparatus is configured so as to be integrated with at least one of the apparatuses and is detachable from the main body of the image forming apparatus.
According to a thirty-third aspect of the present invention, there is provided a process cartridge in the image forming apparatus according to the sixteenth aspect, including a charging device constituting the image forming means, a developing device, and a cleaning device for cleaning the surface of the image carrier. The image forming apparatus main body is configured so as to be detachable from the image forming apparatus main body independently of the image carrying body while being separated from the image carrying body.
A thirty-fourth aspect of the invention is a process cartridge in the image forming apparatus according to the eighteenth aspect, wherein the process cartridge is integrally configured to include the image carrier, the intermediate transfer member, and a supporting member thereof, and the main body of the image forming apparatus. On the other hand, it is detachable.

  According to the first to thirty-fourth aspects, the rear end of the recording medium received by the recording medium receiving surface of the discharge portion is in a state where it does not easily collide with the front end portion of the subsequent recording medium continuously discharged from the discharge port. Since the recording medium can be discharged, it is possible to prevent the recording medium from being discharged poorly. In addition, a dead space is not generated between the intermediate transfer member and the recording medium receiving surface of the discharge unit, and a part of the components constituting each image forming unit is made common to save space inside the apparatus. Therefore, the apparatus can be downsized. Furthermore, since the internal components / devices and units can be easily attached and detached, there is an effect that the maintainability of the internal components / devices and units is excellent.

  Hereinafter, an embodiment in which the present invention is applied to a color printer (hereinafter referred to as “printer”) as an image forming apparatus will be described.

FIG. 1 is a front view illustrating a schematic configuration of a printer according to the present embodiment. The printer includes photosensitive drums 1A and 1B as two image carriers. A static eliminating device L, a cleaning device 2, a charging device 3, and two developing devices 5A and 5B are disposed on the outer periphery of the first photosensitive drum 1A. The photosensitive drum 1A is rotatably supported and rotates in the direction of the arrow in the figure. Light emitted from the lower exposure device 4 is incident between the charging device 3 and the developing device 5B, and optical information is written. The component structure around the second photosensitive drum 1B is the same as that of the first photosensitive drum 1A. In each of the developing devices 5A, 5B, 5C, and 5D, toners as developers of different colors are used. These developing devices 5A, 5B, 5C, and 5D can move in the directions of the arrows in the drawing, respectively, and have a mechanism (not shown) that contacts and separates from the corresponding photosensitive drums 1A and 1B.
Here, the image forming means for forming a toner image on the photosensitive drums 1A and 1B includes the charging device 3, the exposure device 4, the developing devices 5A, 5B, 5C, and 5D. The photosensitive drum 1, the cleaning device 2, the charging device 3, the developing devices 5A, 5B, 5C, 5D and the like are configured as a process cartridge 52 that is integrally incorporated and can be attached to and detached from the apparatus main body. It can be exchanged.

A part of the two photosensitive drums 1A and 1B is in contact with an endless belt-shaped intermediate transfer body (hereinafter referred to as “intermediate transfer belt”) 10 at the primary transfer position. The intermediate transfer belt 10 is supported and stretched between support rollers 11 and 12 as rotating support members so as to be movable in the direction of the arrow in the drawing. On the back side of the intermediate transfer belt 10 (inside the loop), a primary transfer roller 20 and a backing roller 14 as primary transfer means are provided in contact with the photosensitive drums 1A and 1B in the vicinity thereof. An intermediate transfer member cleaning device 25 is provided on the outer peripheral surface side of the intermediate transfer belt 10. The intermediate transfer member cleaning device 25 performs cleaning by wiping off unnecessary toner remaining on the surface of the intermediate transfer belt 10 after the toner image is secondarily transferred to the paper P as a recording medium. The intermediate transfer member cleaning device 25 is configured to be rotatable about a rotation center 25A so that the cleaning blade 25B contacts and separates from the surface of the intermediate transfer belt 10 by a contact / separation mechanism (not shown).
Further, the intermediate transfer belt 10 and the intermediate transfer member cleaning device 25 and the like around the intermediate transfer belt 10 are configured as an intermediate transfer unit 51 which can be integrally attached to and detached from the apparatus main body, and can be replaced when the end of the service life is reached.

  The exposure device 4 is a known laser-type exposure device, and laser light whose intensity is controlled based on image information corresponding to full-color image formation is applied to the surfaces of the uniformly charged photoreceptor drums 1A and 1B. Irradiate to form an electrostatic latent image. As the exposure device 4, a combination of a well-known LED array and an imaging means can be used.

  The photosensitive drums 1A and 1B are obtained by providing an organic semiconductor layer, which is a photoconductive substance, on the surface of an aluminum cylinder having a diameter of about 40 to 100 mm. As the image carrier, a belt-like photosensitive member may be used. It is also possible to employ a photosensitive drum of a type employing amorphous silicon.

The intermediate transfer belt 10 is a seamless endless belt having an electric resistance value that allows a toner image to be transferred from each of the photosensitive drums 1A and 1B. The intermediate transfer belt 10 used in this embodiment is obtained by applying a low surface energy coat as a surface layer on a substrate made of a resin film or rubber having a thickness of 50 μm to 500 μm. The volume resistivity of the entire intermediate transfer belt 10 is in the range of 10 ⁵ to 10 ¹² Ωcm, and the surface resistivity is in the range of 10 ⁶ to 10 ¹³ (Ω / □).

  In FIG. 1, an endless conveying belt 100 as a belt member constituting a recording medium conveying unit is disposed at the right end of the printer. The conveyor belt 100 is supported and stretched between support rollers 111 and 112 as support members so as to be movable in the direction of the arrow in the figure. A secondary transfer roller 120 as a secondary transfer unit is disposed in the vicinity of the support roller 11 that supports the intermediate transfer belt 10 on the back side of the conveyance belt 100 (inside the loop). In addition, a backing roller 115 for pressing the conveyor belt 100 toward the support roller 11 is also provided. By the secondary transfer roller 120, the backing roller 115, and the support roller 11 that supports the intermediate transfer belt 10, the transfer nip in which the intermediate transfer belt 10 and the conveying belt 100 are in contact with each other at a predetermined nip width at the secondary transfer position. Part is formed.

  On the outer peripheral surface side of the conveyor belt 100, a conveyor belt cleaning device 250 provided with a blade 250B for wiping off dust adhering to the surface of the conveyor belt 100 and unnecessary toner is disposed. The dust and waste toner removed by the cleaning device 250 are transported to a collection unit (not shown) by the toner transport unit 250C.

  The transport belt 100 and the transport belt cleaning device 250 are integrally configured as a transport belt unit (transport unit) 250U. The conveyor belt 100 can be brought into contact with and separated from the intermediate transfer belt 10 by swinging the conveyor belt unit 250U with a drive mechanism (not shown) around the rotation fulcrum C.

Since the conveying belt 100 passes near the fixing device 30 as a fixing unit composed of a heating roller 30a and the like, it has heat resistance up to about 200 ° C. and has a volume resistivity of 10 ⁸ to 10 ^10. It is formed of a medium resistance belt member of about Ωcm. In this embodiment, a belt member made of polyimide or polyamide having a base thickness of 50 μm to 500 μm is used.

  The fixing device 30 includes a heating roller 30a with a built-in heat source such as a heater, and fixes the image on the paper P by conveying the paper P onto which the toner image has been secondarily transferred while being held by the heating roller 30a. be able to. Since the fixing device 30 is disposed so as to be positioned on the upper part of the printer, it is difficult for heat to be trapped in the device, and a decrease in reliability due to a temperature rise can be prevented.

  The paper P is stored in paper feeding devices (paper feeding cassettes) 26-1 and 26-2 set in the lower part of the printer. Then, the uppermost sheet P is conveyed one by one by the sheet feeding roller 27 to the position of the registration roller pair 28 through a guide member 29 as a plurality of conveying path forming members.

  In addition to the fixing device 30, paper discharge guide members 31 </ b> A and 31 </ b> B, a paper discharge roller pair 32, and a paper discharge stack unit 40 serving as a paper discharge unit are disposed on the upper portion of the printer.

The paper discharge stack section 40 has a discharge port 41 through which the paper P that passes through the fixing device 30 and is guided by the paper discharge guide members 31A and 31B and sent out by the paper discharge roller pair 32 is discharged. The paper discharge stack 40 has a paper receiving surface 42 as a recording medium receiving surface that receives the paper P discharged from the discharge port 41 as indicated by an arrow A in the figure. The main receiving surface 42a, which is a part of the sheet receiving surface 42, is inclined downward at a constant inclination angle as approaching the discharge port 41, and has a flat inclined surface whose lowermost end is lower than the discharge port 41. (See FIG. 2).
The intermediate transfer belt 10 is stretched by support rollers 11 and 12 so that the upper stretched portion of the intermediate transfer belt 10 inclines and extends along the main receiving surface 42a which is the inclined surface of the discharge stack portion 40. Yes.

  Further, a toner cartridge mounting portion TS is provided above the intermediate transfer belt 10 and below the sheet receiving surface 42 of the paper discharge stack portion 40, and serves as a toner storage portion that can store replenishment toner to be supplied to the developing device. The toner cartridge TC is detachably mounted. The toner cartridge TC is provided for each of four color toners (magenta, cyan, yellow, and black: a, b, c, and d in the drawing). The toner in each toner cartridge is supplied to the corresponding color developing device by a powder pump (not shown).

  The toner cartridge TC can be attached and detached by opening the door D (see FIG. 6 described later) on the front side of the printer main body. The door D is configured to be openable about a rotation axis (not shown) provided at the left end and extending in the vertical direction. This rotation axis is on the right side of the operation panel OP (see FIG. 6 to be described later). Even when the door D is opened, the information displayed on the operation panel OP and the inside of the paper feed cassette are viewed from the front operation position. It is possible.

A heat insulating member W is provided as a heat shield means between the toner cartridge mounting portion TS on which the toner cartridge TC is mounted and the fixing device 30 having a heat source. With this heat insulating member W, heat transfer from the fixing device 30 to the toner cartridge mounting portion TS can be prevented, and replenishment toner in the toner cartridge TC can be prevented from being melted and fixed due to repeated heating and cooling. As the heat insulating member W, for example, a resin, a flocked resin, a laminate of these materials so as to have an air layer, or the like can be used.
Further, as the heat shield means, a ventilation means for circulating air between the toner cartridge mounting portion TS and the fixing device 30 may be provided. As illustrated in FIG. 1, this ventilation means includes a fan F2 attached to the side plate side of the printer main body, and an air flow path that passes between the toner cartridge mounting portion TS and the fixing device 30 and reaches the fan F2. Can be configured. When outside air is taken in by this ventilation means, the surroundings are cooled, which is more effective. Further, among the toner cartridges TC, a toner cartridge d that is particularly close to the fixing device 30 may be formed of a heat insulating material, or a portion of the toner cartridge mounting portion TS where the toner cartridge d is mounted may have a heat insulating structure. It is effective.

  A swing unit 50 as a moving unit on the right side of the printer body on the conveyance belt 100 can swing about a switching shaft 50A as a swing shaft to a position shown in FIG. As shown in FIG. 3, by swinging the swing unit 50, the transport path of the paper P is opened, and the jam processing when the transport failure of the paper P occurs is facilitated. Further, by opening the swing unit 50, it is easy to take out the conveyor belt unit 250U including the conveyor belt 100 described above.

  At the upper part of the swing unit 50, a fan F1 that operates to exhaust air outside the apparatus is provided to prevent the temperature inside the apparatus from rising excessively. In addition, electrical / control devices E1 and E2 including a low-voltage power supply, a high-voltage power supply, a substrate, and the like are disposed on the left side portion of the printer main body.

In addition to the transport belt 100, the swing unit 50 forms a double-sided image for transporting the paper P that has passed through the fixing device 30 so as to re-pass the secondary transfer position with the front and back surfaces reversed. Conveying means are provided. This double-sided image forming conveying means includes a switching guide member G1 that can swing around a rotation axis G0, a film-shaped switching guide member G2, a refeeding conveyance path PG1, PG2, PG3, PG4, and a conveyance roller. It is comprised by R1-R4 etc.
When images are formed on both sides of the paper P, first, images are formed on one side of the paper P. Then, after being fixed by the fixing device 30, the paper P guided to the switching guide member G1 is held by the transport roller R1 so as to press the film-like guide member G2, and is fed into the refeed paper transport path PG1. Along the way. After the rear end has passed the guide member G2, the transport roller R1 is rotated in the reverse direction while being held by the transport roller R1. The sheet P enters under the guide member G2, and the side that has been the rear end until now becomes the front end, and is conveyed by the conveyance rollers R2, R3, and R4, and is conveyed to the refeeding conveyance paths PG2, PG3, and PG4. Along the way to the registration roller 28. Then, the color toner image formed on the intermediate transfer belt 10 is transferred again, so that color images are formed on both sides of the paper P.

  When normal image formation is performed in the printer having the above-described configuration, first, toner image formation on the photosensitive drums 1A and 1B and transfer to the intermediate transfer belt 10 are performed. During this time, the conveyor belt unit 250U is swung around the fulcrum 250C so that the conveyor belt 100 is separated from the intermediate transfer belt 10.

In the toner image forming operation on the photosensitive drums 1A and 1B, light from an LD (semiconductor laser) light source (not shown) of the exposure device 4 is uniformly charged by the charging device 3 through an optical component such as a polygon mirror. The surface of the photosensitive drum 1A is irradiated. By this irradiation, an electrostatic latent image corresponding to writing information (information corresponding to color) is formed. In this example, optical information to be developed with magenta toner is written. Here, the surface of the photosensitive drum 1A is exposed so that a positive electrostatic latent image is formed. As a result, the image transferred onto the paper P via the intermediate transfer belt 10 becomes a normal image.
The electrostatic latent image for magenta on the photosensitive drum 1A is moved to a position where the developing device 5A containing magenta toner can be developed and developed. The toner image (developed image) of this magenta toner is primarily transferred by the primary transfer roller 20 onto the surface of the intermediate transfer belt 10 that moves in synchronization with the photosensitive drum 1A. The remaining toner on the surface of the photosensitive drum 1A after the primary transfer is cleaned by the cleaning device 2 and discharged by the charge removing device L to prepare for the next image forming cycle.

  The intermediate transfer belt 10 carries the magenta toner image transferred on the surface and moves in the direction of the arrow. On the surface of the other photosensitive drum 1B, light information to be developed in yellow color is written to form an electrostatic latent image for yellow, which is developed by the developing device 5C containing yellow toner. The This yellow toner image is superimposed on the magenta toner image already formed on the intermediate transfer belt 10.

  When the toner images of the two colors (magenta and yellow) move together with the intermediate transfer belt 10 to the photosensitive drum 1A, optical information corresponding to black is synchronously written on the photosensitive drum 1A. An electrostatic latent image is formed. This black electrostatic latent image is developed by the developing device 5B containing black toner. Then, the black toner image on the photosensitive drum 1A is primary-transferred over the surface of the intermediate transfer belt 10 as the third color in the same manner as described above. On the surface of another photosensitive drum 1B, light information to be developed in cyan color is written to form an electrostatic latent image for cyan, which is developed by a developing device 5D containing cyan toner. The This cyan toner image is superimposed on the three-color toner image already formed on the intermediate transfer belt 10, thereby forming a four-color full-color image on the intermediate transfer belt 10. In this way, in the full-color image forming mode composed of four color toners, the intermediate transfer belt 10 rotates twice and passes through the primary transfer position facing the photosensitive drums 1A and 1B twice.

  When the intermediate transfer belt 10 rotates and moves to a predetermined position, paper feeding from the paper feeding device (paper feeding cassette) 26 is started. When the paper feed roller 27 rotates in the direction of the arrow, the uppermost paper P in the paper feed device (paper feed cassette) 26 is pulled out and conveyed to the registration roller pair 28. The toner image on the surface of the intermediate transfer belt 10 is transferred by the secondary transfer roller 120 to one surface of the paper P sent between the intermediate transfer belt 10 and the conveyance belt 100 via the registration roller pair 28. At this time, the intermediate transfer belt 10 and the conveyance belt 100 are running while being in contact with each other. Further, the paper P is transported upward, and the paper P is transported at a timing such that the position of the image becomes a normal position during the secondary transfer.

  In this embodiment, the polarity of the toner of the image formed on the photosensitive drums 1A and 1B is negative. Accordingly, by applying a positive charge to the primary transfer roller 20, the toner formed on the photosensitive drums 1 </ b> A and 1 </ b> B is transferred to the intermediate transfer belt 10. Further, by applying a positive charge to the secondary transfer roller 120, the toner image formed on the intermediate transfer belt 10 is transferred to one surface of the paper P.

  The sheet P on which the toner image is transferred on the surface in the above process is sent to a certain area of the fixing device 30, and the toner images (both sides) on the sheet P are fixed at a time. Then, after passing through the guide members 31A and 31B, the paper discharge roller pair 32 discharges the paper from the discharge port 41 onto the paper receiving surface 42 of the paper discharge stack unit 40 provided at the top of the main body frame.

  Dust and toner adhering to the conveyance belt 100 after the secondary transfer are scraped off by the cleaning blade 250B and collected in a storage unit (not shown) by the toner conveyance unit 250C.

  When a single color image is formed instead of a full-color image with the printer having the above configuration, the secondary transfer process to the paper P is performed without rotating the intermediate transfer belt 10 twice, and the travel distance of the intermediate transfer belt 10 is increased. Can be shortened.

  In the printer having the above-described configuration, control commands such as various parameter settings from the operator can be issued from an operation panel OP shown in FIG. 5 described later or the keyboard of the host computer HC. When image formation on both sides of the paper P is executed, it can be selected by a double-sided button (not shown) provided on the operation panel (OP). The selection of special paper and the selection of the paper feed cassette 26 can be selected by a setting button for the paper feed button. In a system in which a host computer is connected as an image forming system (see FIG. 6 described later), it is convenient to display a setting screen on the display of the host computer HC so that setting instructions can be given on the screen. .

In the printer having the above-described configuration, the heat energy applied to the paper P by the fixing device 30 is smaller when a single color image is formed than when a full color image is formed. For this reason, at the time of forming a monochromatic image, for example, control is performed such as reducing or not supplying power to a heat source located on the side without an image.
In addition, when double-sided image formation is performed in which images are formed on both sides of the paper P, an even page image is formed first, and an odd page image is formed next. On odd number pages 42 are placed on the lower surface. Therefore, when the paper P is taken out from the paper discharge stack section 40, it is convenient because the page order is aligned. When double-sided image formation is performed, the rear end of the paper P on which the image is formed on one side at the time of refeeding the paper P is now the front and enters the secondary transfer position. To do. Therefore, the formation of the electrostatic latent image for the second surface on the photosensitive drums 1A and 1B is controlled so as to be created from the side corresponding to the rear end.

FIG. 4 is a front view illustrating a schematic configuration of a printer according to another embodiment. The basic configuration of this printer is the same as that of the printer shown in FIG. 1, and common portions are denoted by the same reference numerals and description thereof is omitted.
The printer shown in FIG. 4 is not the laser type exposure apparatus used in the printer shown in FIG. 1, but an exposure apparatus 4 comprising an LED array provided independently for each photosensitive drum in order to further reduce the size of the apparatus. Is used.
Further, in the printer of FIG. 4, in order to reduce the size in the left-right direction in the figure while securing a predetermined peripheral length of the intermediate transfer belt 10, the travel path of the intermediate transfer belt 10 is formed in a triangular shape. Two support rollers 11, 12, and 13 are stretched. The photosensitive drums 1 </ b> A and 1 </ b> B are arranged side by side so as to face the outer peripheral surface of the lower stretch portion that extends in the horizontal direction of the intermediate transfer belt 10. Further, in the printer of FIG. 4, the size in the left-right direction in the figure is reduced to reduce the size without providing a conveying means for forming a double-sided image.
Further, in the printer of FIG. 4, the process cartridge 53 can be replaced when the end of its service life is reached. The process cartridge 53 includes the photosensitive drums 1A and 1B, the cleaning device 2, the charging device 3, the exposure device 4, and the developing devices 5A, 5B, 5C, and 5D, and the intermediate transfer belt 10 and the cleaning device 25 integrally. It can be attached to and detached from the main body.

  In the printer of FIG. 4 as well, the swing unit 50 on the conveyance belt 100 side on the right side of the printer main body can swing about the opening / closing support shaft 50A to the position shown in FIG. As shown in FIG. 5, by swinging the swing unit 50, the transport path of the paper P is opened, the jam processing when the transport failure of the paper P occurs becomes easy, and the unit including the transport belt 100. It is also easy to remove.

FIG. 6 is a front view showing a schematic configuration of a printer according to still another embodiment. The basic configuration of this printer is the same as that of the printer shown in FIG. 1, and common portions are denoted by the same reference numerals and description thereof is omitted.
The printer shown in FIG. 6 is a so-called tandem color image forming apparatus provided with four photosensitive drums 1A, 1B, 1C, and 1D, unlike the printer shown in FIG. The image forming unit including each photoconductive drum includes a charging device 3, a developing device 5, a charge eliminating device L, and a cleaning device 2 as opposing components around the photoconductive drum. The photosensitive drums 1A, 1B, 1C, and 1D are irradiated with light information by a laser beam of color data branched from a multi-beam type exposure device 4 that is commonly used for each image forming unit.
Further, in the printer of FIG. 6, in order to reduce the size in the thickness direction of the left end portion in the drawing while securing a predetermined peripheral length of the intermediate transfer belt 10, the shape of the travel path of the intermediate transfer belt 10 is triangular. The three support rollers 11, 12, and 13 are stretched. The photosensitive drums 1 </ b> A, 1 </ b> B, 1 </ b> C, and 1 </ b> D are arranged in parallel in an oblique direction so as to face the outer peripheral surface of the lower stretch portion of the intermediate transfer belt 10. Further, in the printer of FIG. 6, the moving unit 50 is not provided with a conveying means for forming double-sided images, and the size in the left-right direction in the drawing is reduced to further reduce the size.

  In the printer shown in FIG. 6, the intermediate transfer unit 51 including the intermediate transfer belt 10 as shown in FIG. 7 is rotated in the clockwise direction indicated by an arrow E in FIG. It can be swung. Accordingly, the intermediate transfer belt 10 can be separated from the photosensitive drums 1A, 1B, 1C, and 1D.

  The photosensitive member cleaning device 2, the charging device 3, the charge eliminating device L, and the developing device 5, which are components constituting the image forming means for each photosensitive drum, all serve as process cartridges (not shown) while ensuring a proper positional relationship. It is integrally configured as an image forming unit and is housed in an image forming frame 54F. Then, when the rails R as the two left and right rail members of the image forming frame 54F are lowered, the opposing constituent elements such as the respective charging devices 3 constituting the image forming means are moved to the photosensitive drums 1A, 1B, 1C, It can be separated from 1D. In this manner, the intermediate transfer unit 51 including the intermediate transfer belt 10 and the image forming frame 54 containing the components of the image forming means are separated from the photosensitive drum, and each is pulled out toward the paper surface of FIG. 6 for maintenance. It can be done. In this separated state, the photosensitive drums 1A to 1D can be individually pulled out from the shaft 1 ', so that the photosensitive drums 1A to 1D can be easily replaced when the end of their service life is reached.

The stretch shape of the intermediate transfer belt 10 in the intermediate transfer unit 51 and the size of the gap S1 in the upper space formed between the upper stretch portion of the intermediate transfer belt 10 and the toner cartridge TC are as follows. Is set. As described above, the intermediate transfer unit 51 is swung when the photosensitive drum is attached or detached. Therefore, when the intermediate transfer unit 51 is swung, the tension shape and the upper portion of the intermediate transfer belt 10 are prevented so that the upper tension portion between the support rollers 11 and 12 of the intermediate transfer belt 10 and the toner cartridge TC do not come into contact with each other. The size of the space gap S1 is set.
The size of the gap S2 in the lower space formed between the developing device 5 and the exposure device 4 of the image forming means is set as follows. As described above, when attaching or detaching the photosensitive drum or performing maintenance of the charging device or the like, the image forming frame 54F in which the charging device 3 or the like is accommodated is moved downward. Accordingly, the size of the gap S2 in the lower space is set so that the lower end of each developing device 5 and the exposure device 4 do not come in contact with the movement of the image forming frame 54F. By setting in this way, it is possible to replace the photosensitive drum without damaging it. Further, components such as a charging device constituting the image forming means provided for each photosensitive drum face the surface of the photosensitive drum below the horizontal plane including the central axis of the corresponding photosensitive drum. Are arranged as follows. With such an arrangement, it is possible to lower the image forming frame 54F including an image forming unit integrally configured with a charging device or the like downward in the vertical direction.

FIG. 8 is an explanatory diagram of a moving mechanism unit that moves the intermediate transfer unit 51 and the image forming unit 54 as shown in FIG.
One end 51A of the intermediate transfer unit 51 is pressed against the stopper 67 by a short roller 68 pressed by a spring 69 from above, and the intermediate transfer belt 10 is positioned at a normal position. The lever member 71 is supported so as to be rotatable about a support shaft 65. At the lower end of the lever member 71, a knob 71A for operation by the operator is provided. A cam portion 73 is provided at the upper end of the lever member 71. The stopper 66 restricts the clockwise rotation of the lever member 71. Under the support shaft 65, a pin 63 fixed to a plate cam 60 as a cam member is engaged with an elongated hole 72 as an engaging portion provided in the lever member 71. The plate cam 60 has two elongated holes 61 extending in the horizontal direction, and can move in the horizontal direction while being guided by two pins 64 provided in the image forming apparatus main body. Slopes 62A are formed at the upper ends of both ends of the plate cam 60, and horizontal planes 62B are formed on the left and right sides thereof. The inclined surfaces 62A and the horizontal surface 62B serve as contact surfaces with which the lower end portion of the rail R as a rail member supporting the image forming frame 54F that is a case member of the image forming unit 54 contacts from above. When the rail R rides on the horizontal surface 62B of the plate cam 60, the image forming unit 54 is positioned at the image forming position. The rail R is attached to the image forming apparatus main body so as to be movable in the vertical direction. Further, a slide rail R ′ as a movable rail member incorporated in the rail R can slide in a direction perpendicular to the paper surface of FIG. An image forming frame 54F (portion indicated by a one-dot chain line in FIG. 12) is fixed to the slide rail R ′. The image forming frame 54F forms an image as a process cartridge in which each opposing component (image forming element) having development, charging, cleaning, and charge removal functions provided facing the photosensitive drums 1A to 1D is formed into a cartridge. The unit 54 is held by a holding unit (not shown).

In the moving mechanism having the above configuration, when the knob 71A of the lever member 71 is operated to move the lower side of the lever member 71 in the direction of arrow F, the lever member 71 rotates counterclockwise. At this time, the lever member 71 rotates while the cam portion 73 above the lever member 71 supports the one end 51 </ b> A of the intermediate transfer unit 51. By the rotation of the lever member 71, the intermediate transfer unit 51 rotates about the center 11A of the support roller 11 as a swing center, and is separated from the photosensitive drums 1A, 1B, 1C, 1D. The intermediate transfer unit 51 has its one end 51A (left end in FIG. 8) along the upper surface of the cam portion 73 and the other end (right end in the drawing) along the support roller 11 and is pulled out toward the front side of the page in FIG. be able to.
Further, as the lever member 71 rotates in the direction of arrow F, the plate cam 60 moves to the right, and the rail R descends along the slope 62A of the plate cam 60. An image forming frame 54A holding each image forming unit 54 is attached to a slide rail R ′ incorporated in the rail R. Therefore, in the state where the rail R is lowered, as shown in FIG. 9, each image forming unit 54 is moved in a state where the opposing component (image forming element) constituting the image forming means is separated from the photosensitive drum. The entire image forming frame 54F can be pulled out. By pulling out the image forming frame 54F in this manner, the image forming unit 54 as a process cartridge in which the opposing components (image forming elements) are integrally configured can be replaced or maintained.

FIG. 9 shows a case where one image forming unit (process cartridge) 54A, 54B,... Including the above-described opposing component (image forming element) is configured for each photosensitive drum. However, the above-described opposing components (image forming elements) for the four photosensitive drums can be combined into one image forming unit 54.
Further, a black image is formed at the rightmost photosensitive drum 1D, and only the above-described opposing component (imaging element) with respect to the photosensitive drum 1D is integrally configured as an independent image forming unit. May be. Then, the opposing constituent elements (imaging elements) for the photosensitive drums 1A, 1B, and 1C that form other color images may be combined into a single imaging unit. Thus, when the black image forming unit is provided independently, only the black image forming unit that is frequently used can be replaced, which is economically convenient.

  Further, in the configuration example of FIG. 8, the case where the moving mechanism unit is configured to rotate the lever member 71 to separate the intermediate transfer unit 51 and the image forming unit 54 from the photosensitive drum at the same time has been described. However, the moving mechanism unit may be configured to be separated from the intermediate transfer unit 51 and the image forming unit 54 individually.

Further, in FIG. 8, a protruding portion (operation portion) 60A is formed by protruding the right end portion of the plate cam 60 toward the swing unit (moving unit) 50 as indicated by a broken line, and the swing unit (moving unit). When moving 50, the exposed protrusion 60A may be pulled. When the operator pulls the protruding portion 60A, the plate cam 60 moves to the swing unit (moving unit) 50 side, and the lever member 71 can be rotated counterclockwise.
Further, when the plate cam 60 is appropriately pressed with a spring so as to move to the right side and the protrusion 60A is in contact with a part of the swing unit (moving unit) 50, the swing unit (moving unit). When 50 is released from the main body of the image forming apparatus, the plate cam 60 is moved in conjunction with the movement of the swing unit (moving unit) 50 to open the conveyance path, and the lever member 71 can be rotated. .
Further, the cam portion 73 of the lever member 71 may be formed so as to be operable by the operator so as to rotate the lever member.

  Further, as shown in FIG. 8, when the opposing component (imaging element) is moved downward and separated from the photosensitive drum, the opposing component and the plate cam 60 of the moving mechanism part interfere with each other. In order to avoid this, it is preferable to provide a space S ′ between the image forming frame 54 </ b> F that accommodates the opposing component (image forming element) and the plate cam 60 of the moving mechanism unit.

  6 and 7, the moving unit 50 including the conveyance belt 100 on the right side of the printer main body can be moved to the position shown in FIG. 7 by the extendable guide rail mechanism GR via the support member SPT. It is like that. By moving the moving unit 50 in this way, the conveyance path of the paper P is almost opened, jam handling when the conveyance failure of the paper P occurs, cleaning of the charge-eliminating charger CH for separation, cleaning of the conveyance guide 29, and registration. Maintenance such as cleaning of the roller pair 28 is facilitated. Further, the transport unit 250U including the transport belt 100 can be easily taken out. In particular, since one roller 28A of the registration roller pair 28 and a part 29A of the conveyance guide 29 are provided on the conveyance unit 250U side, the maintenance can be facilitated. The transport unit 250U can be taken out from the moving unit 50 by gripping the handle HD at the top and pulling it up in the direction of arrow D. The lower surface of the transport unit 250U is formed in a flat shape, and can be placed on a flat surface of a desk or the like in a stable state.

  FIG. 10 is a schematic configuration diagram of a transport unit 250U according to a modified example that can be attached to and detached from the moving unit 50 of the printer of FIGS. A blade cleaner 260 is brought into contact with one roller 28A of the registration roller pair 28, and foreign matters such as paper dust scraped off from the roller 28A are collected and stored in the collection container 260A. The collection container 260A may be configured integrally with a container for storing the dust scraped off by the conveyor belt cleaning device 250 and waste toner. Further, in FIG. 10, it may be configured such that these containers can be taken out in the front direction perpendicular to the paper surface, and discarded as appropriate.

  In addition, the primary transfer unit and the secondary transfer unit in the printer shown in FIGS. 1 and 4 are respectively a roller type that contacts the intermediate transfer belt 10 and the conveyance belt 100 (primary transfer roller 20, secondary transfer roller 120). However, a brush-shaped transfer member, a member formed in a roller shape with a brush, or the like can also be employed. Furthermore, a non-contact discharge type (charger) can also be used.

FIG. 11 illustrates an image forming system in which the printers 301 and 302 illustrated in FIGS. 1, 4, and 6 are connected to a host computer 300 or the like via a wired network cable 303. In this image forming system, the printers 301 and 302 mainly serve as output devices for the host computer 300. For example, an image read by a scanner 304 connected to the host computer 300 can be edited as appropriate and output from the printers 301 and 302.
The printers 301 and 302 and the host computer 300 may be connected by a wireless communication network instead of a cable.

  In the image forming system having the above-described configuration, it is possible to instruct or input the image forming process conditions of the image to be output, the paper discharge form of the paper P, and the like according to the guide displayed on the display of the host computer 300. Further, the status of the printers 301 and 302 can be displayed on the display of the host computer 300 to notify the operator.

The printer 302 shown in the lower part of FIG. 11 is in a state where the door D is opened and the image forming unit can be maintained, and the paper cassette 26-2 is pulled out and the paper P is replenished and replaced. Yes.
By opening the door D, the intermediate transfer unit 51 and the process cartridges 52 and 53 can be pulled out with the exposure apparatus 4 left in the main body. With these pulled out, the photosensitive drums 1A and 1B, the intermediate transfer belt 10 and the like can be attached and detached. The process cartridges 52 and 53 are guided by guide rails (not shown) so that they can be pulled out easily and reliably. Since the door D is supported by a hinge arranged in the vertical direction, even when the door D is opened, the visibility of maintenance parts below the door D is good. Although not shown, a seal member is provided so that the components of the exposure apparatus 4 are not contaminated by toner or the like.

As described above, according to the present embodiment, the paper P is transported so as to pass through the secondary transfer position and the fixing position in the fixing device 30 upward, so that the leading edge of the paper P does not hang down due to its own weight. The sheet P can surely enter the secondary transfer position and the fixing position. Therefore, the conveyance failure of the paper P can be prevented.
Further, the main receiving surface 42 a which is at least a part of the paper receiving surface 42 of the discharge stack portion 40 is inclined downward at a certain inclination angle as it approaches the discharge port 41 side, and its lowermost end is lower than the discharge port 41. It is a low flat inclined surface. For this reason, as shown in FIG. 12, the sheet P discharged from the discharge port 41 is inclined on the sheet receiving surface 42 formed of a flat inclined surface in a state where the rear end is inclined so as to be lower than the discharge port 41. Can receive. Accordingly, a plurality of sheets can be discharged in a state in which the rear end of the sheet P received by the sheet receiving surface 42 does not easily collide with the leading end of the subsequent sheet P discharged continuously from the discharge port 41. P discharge failure can be prevented. In particular, the printer of this embodiment is effective when the recording medium is a strong (high rigidity) material such as thick paper or an OHP sheet.
Further, the upper stretch portion of the intermediate transfer belt 10 extends in an inclined manner along the sheet receiving surface 42 of the discharge stack portion 40. For this reason, the upper stretch portion of the intermediate transfer belt 10 and the sheet receiving surface 42 of the discharge stack portion 40 are brought close to each other so that no dead space is generated between them, and the space inside the apparatus can be saved. In addition, since the plurality of photosensitive drums are arranged so as to face the lower stretched portion of the intermediate transfer belt 10, a plurality of image forming units for the respective photosensitive drums are collectively arranged below the intermediate transfer belt 10. Each image forming unit is disposed at a relatively close position. Therefore, unlike the case where the image forming unit is provided separately on the upper and lower stretched portions of the intermediate transfer belt, some of the components constituting each image forming unit (in this embodiment, the exposure apparatus). 4) can be shared, and further space saving inside the apparatus can be achieved. Therefore, the apparatus can be reduced in size. Further, when replacing internal components such as the intermediate transfer belt 10 and the photosensitive drum or units such as the intermediate transfer unit and the process cartridge, the photosensitive drums are separated from each other only at the lower stretch portion of the intermediate transfer belt 10. What is necessary is just to evacuate. This makes it easier to attach and detach internal components and units than when a plurality of photosensitive drums are arranged so as to face both the upper and lower stretch portions of the intermediate transfer belt. Become. Therefore, the maintainability of internal components and units is excellent.

  Further, according to the present embodiment, the image forming means such as the photosensitive drums 1A and 1B, the charging device 3, the developing devices 5A, 5B, 5C, and 5D are transferred from the fixing device 30 having the heat source. 10 is provided on the lower side. Thus, a toner image can be formed on the photosensitive drum without being adversely affected by the heat generated from the fixing device 30. Further, by tilting the upper stretch portion of the intermediate transfer belt 10 along the sheet receiving surface 42, the wedge-shaped space generated below the intermediate transfer belt 10 is effective for the layout of the components of the image forming means. Available. In addition, in the configuration of the printer according to the present embodiment, the lower stretch portion of the intermediate transfer belt 10 is located at the secondary transfer position from the portion facing the photosensitive drum that is far from the secondary transfer position among the plurality of photosensitive drums. It moves toward the portion facing the photosensitive drum located near the position. For this reason, the distance from the primary transfer position for each photosensitive drum to the secondary transfer position for transfer onto the paper P can be shortened. Accordingly, the time (first print time) from the start of the printing operation until the first sheet P is output can be shortened.

  In particular, as in the printer shown in FIG. 1 of the present embodiment, when the image forming unit is configured to form toner images of two different colors on each of the photosensitive drums 1A and 1B, 4 A full-color image can be formed without using one photosensitive drum. Therefore, it is possible to further reduce the size of a printer that can form a full-color image.

  In addition, according to the present embodiment, the transport unit that transports the paper P supports and transports the paper P along the transport path that faces the intermediate transfer belt 10 at the secondary transfer position and passes through the secondary transfer position. The conveyor belt 100 is stretched around a plurality of support rollers 111 and 112. Therefore, the transportability of the paper P can be secured and the reliability can be increased.

  Further, according to the present embodiment, since the conveyance belt 100 is formed of a heat resistant material, even if the conveyance belt 100 is disposed close to the fixing device 30 having a heat source, the conveyance belt 100 is altered and deformed. Does not occur. Furthermore, by bringing the conveying belt 100 closer to the fixing device 30, the paper P having unfixed toner can be reliably guided to the fixing device 30, and the occurrence of an abnormal image can be prevented.

  Further, according to the present embodiment, the swing unit (moving unit) 50 that can swing integrally with the conveyor belt 100 about the opening / closing support shaft 50A is swung to the positions shown in FIGS. 2, 4, and 7, respectively. It can be moved (moved). This swinging (moving) can open the transport path of the paper P, so that it is easy to handle a jam when a transport failure such as the paper P stops in the middle of the transport path, and maintenance in the apparatus. Will also be easier.

  Further, according to the present embodiment, both sides of the paper P that have passed through the fixing device 30 are conveyed to the swing unit (moving unit) 50 so that the paper P passes through the secondary transfer position with the front and back surfaces reversed. A conveying unit for image formation is provided. Therefore, it is possible to form an image on both sides of the paper P.

  Further, according to the present embodiment, the surface of the photosensitive drum among the components constituting the image forming unit and the intermediate transfer belt 10 is separated upward from the plurality of photosensitive drums 1A, 1B, 1C, and 1D. The intermediate transfer belt 10 and the counter component are configured to be movable so that the counter components (the cleaning device 2, the charging device 3, the developing device 5, and the charge eliminating device L) that face each other are separated downward. . Further, only the photosensitive drums 1A, 1B, 1C, and 1D can be attached to and detached from the apparatus main body in a state where the intermediate transfer belt 10 and the above-described opposing components are separated from the photosensitive drums 1A, 1B, 1C, and 1D. Has been. Therefore, it is possible to replace the photosensitive drum as a single product, not as a process cartridge, and it is not necessary to replace the intermediate transfer belt and the above-described opposing components that are not required to be replaced while remaining in the apparatus. Burden can be reduced. In the case of a long-life type whose surface of the photoconductor drum is reinforced (for example, a type using amorphous silicon), there is almost no opportunity to replace the photoconductor drum, so it is convenient that it can be attached and detached separately from other replacement parts and units. is there.

Further, according to the present embodiment, the conveyance belt unit 250U that is integrally configured to include the conveyance belt 100 and a part of the conveyance path forming member is provided. The transport belt unit 250U is detachable from the swing unit (moving unit) 50 when the swing unit (moving unit) 50 is moved. Accordingly, maintenance work of the conveyor belt unit 250U is facilitated.
As shown in FIG. 6, the conveyor belt unit 250U may include a blade cleaner 260 as a cleaning unit that cleans one roller 28A of the registration roller pair 28 as a conveyor member. In this case, foreign matters such as paper dust adhering to the registration roller 28A can be removed by the blade cleaner 260, thereby preventing image loss due to foreign matters such as paper dust adhering to the paper P image. can do. Further, it is possible to prevent the foreign matter such as paper dust from adhering to the fixing roller 30a located on the downstream side in the transport direction and deteriorating its surface.
Furthermore, as shown in FIG. 6, a collection container 260 </ b> A may be provided as a storage unit that stores foreign matters such as paper dust scraped off by the blade cleaner 260. In this case, by collecting the foreign matter in the collection container 260A, it is possible to prevent contamination in the image forming apparatus and facilitate the disposal process.

Further, according to the present embodiment, a plurality of toner cartridges TC that store toner of each color to be supplied to the developing devices (5A, 5B, 5C, 5D) are detachably provided. The toner cartridges TC are arranged between the intermediate transfer belt 10 and the sheet receiving surface 42 of the discharge stack portion 40 along the upper stretched portion of the intermediate transfer belt 10 and the main receiving surface (inclined surface) 42a of the discharge portion. It is installed. Accordingly, the toner cartridge TC can be easily replaced by moving the toner cartridge TC along the upper stretched portion of the intermediate transfer belt 10 and the recording medium receiving surface 42 to the front side of the apparatus that can be operated by the operator.
In addition, since a heat shield means is provided between the toner cartridge mounting portion TS and the fixing device 30 having a heat source, the replenishing toner in the toner cartridge TC is prevented from being melted and fixed due to repeated heating and cooling. it can.

Moreover, according to this embodiment, when the said heat insulation means is comprised using the heat insulation member W, the space for heat insulation means is narrowed and it is advantageous at the point of aiming at size reduction of an apparatus.
In addition, the toner cartridge TC itself may be formed of a heat insulating material. In this case, it is not necessary to provide a separate heat insulating member, which is preferable in terms of downsizing of the apparatus.

  Further, in the present embodiment, the heat shield unit may be configured using a ventilation unit that circulates air between the toner cartridge mounting unit TS and the fixing device 30 having a heat source. In this case, since a higher cooling effect can be obtained as compared with the case where only the heat insulating member W is provided, the melting and fixing of the toner can be more reliably prevented.

  Further, according to the present embodiment (the printer of FIG. 1), the intermediate transfer unit 51 including at least the intermediate transfer belt 10 and the support rollers 11 and 12 as support members thereof is provided. The intermediate transfer unit 51 is configured to be detachable from the printer body by moving in a direction perpendicular to the surface movement direction of the intermediate transfer belt 10 and along the upper stretch portion of the intermediate transfer belt 10 and the paper receiving surface 42. Has been. By pulling out the intermediate transfer unit 51 to the front side, maintenance and replacement of the intermediate transfer belt 10 and the like are facilitated.

  Further, according to the present embodiment (the printer of FIG. 6), since the predetermined space S1 is provided between the toner cartridge TC and the intermediate transfer belt, the intermediate transfer belt 10 is separated from the photosensitive drums 1A to 1D. Therefore, the toner cartridge TC and the intermediate transfer belt 10 do not interfere with each other when moved. Therefore, the intermediate transfer unit 51 can be pulled out to the front side, and the intermediate transfer belt 10 and the like can be reliably maintained and replaced.

Further, according to the present embodiment (the printer of FIG. 1), the process cartridge 52 including the photosensitive drums 1A and 1B and at least one of the charging device 3, the developing devices 5A, 5B, 5C, and 5D and the cleaning device 2 is provided. I have. The process cartridge 52 is configured to be detachable from the printer main body by moving in a direction perpendicular to the surface movement direction of the intermediate transfer belt 10 and along the upper stretch portion of the intermediate transfer belt 10 and the sheet receiving surface 42. ing. By pulling out the process cartridge 52 to the front side, the maintenance and replacement of the photosensitive drum and the like can be easily performed.
The intermediate transfer unit 51 and the process cartridge 52 may be combined into a single process cartridge 53 as in the printer of FIG.

  Further, according to the present embodiment (the printer of FIG. 7), a process cartridge (image forming) that is integrally configured to include at least the charging device 3 and the developing devices 5A, 5B, 5C, and 5D that constitute the image forming unit. Unit) 54. The process cartridge 54 is configured to be detachable from the image forming apparatus main body independently of the photosensitive drum while being separated from the photosensitive drum by the moving mechanism unit of FIG. In this case, independent of the photosensitive drum, maintenance / replacement of the opposing components such as the charging device 3 and the developing devices 5A, 5B, 5C, and 5D facing the photosensitive drum can be easily performed.

  The process cartridges (image forming units) 52 and 54 may be integrally provided for all or part of the plurality of photosensitive drums 1A to 1D. For example, when the process cartridges (image forming units) 52 and 54 are integrally provided for all of the photosensitive drums 1A to 1D, the photosensitive drums 1A to 1D and the photosensitive drums 1A to 1D are opposed to the photosensitive drums 1A to 1D. Opposing components such as the charging device 3 and the developing devices 5A, 5B, 5C, and 5D can be attached and detached collectively. Further, process cartridges (image forming units) 52 and 54 for one photosensitive drum for forming a black image, and process cartridges (image forming units) 52 for three photosensitive drums for forming a color image. , 54, it is possible to individually replace only the black process cartridge (image forming unit) that is frequently used.

  Further, according to the present embodiment, the toner cartridge TC as the toner storage portion is placed in a direction perpendicular to the surface movement direction of the intermediate transfer belt 10 and along the upper stretch portion of the intermediate transfer belt 10 and the sheet receiving surface 42. It is configured to be movable and detachable from the printer body. Accordingly, the toner can be easily replenished by pulling out the toner cartridge TC in which the toner is empty and replacing the toner cartridge TC or replenishing the toner cartridge TC with toner.

  Further, according to the present embodiment (the printer of FIG. 8), the charging device 3 and the developing devices 5A, 5B, and 5C facing the plurality of photosensitive drums 1A to 1D among the constituent elements constituting the image forming unit. , 5D and the like are provided with a moving mechanism unit for moving the opposing component downward. Then, when the opposing component is moved downward to be separated from the photosensitive drums 1A to 1D and taken out, the opposing component and the moving mechanism are arranged so as not to interfere with each other. Is provided with a space S2 ′. Accordingly, the process cartridge (image forming unit) 54 including the above-described opposing components can be pulled out toward the front side to reliably perform maintenance and replacement of the opposing components such as the charging device 3 and the developing devices 5A, 5B, 5C, and 5D. it can.

  Further, according to the present embodiment (the printer of FIG. 8), the moving mechanism portion has a contact surface with which the lower end portion of the rail R supporting the opposing component contacts from above, and the rail R A plate cam 60 is used as a cam member movable in a direction crossing the abutting direction of the lower end, and the opposing component is separated from the image forming position and the photosensitive drum by the movement of the plate cam 60. The contact surface of the plate cam 60 is formed. By configuring the moving mechanism portion using such a plate cam 60, the plate cam 60 is brought into contact with the contact surface of the plate cam 60 by a simple operation of reciprocating in the cross direction (horizontal direction). The process cartridge (image forming unit) 54 including the opposed components can be moved between the image forming position and the separated position by moving the rail R up and down.

  Further, according to the present embodiment (the printer of FIG. 8), the intermediate transfer belt 10 is moved along with the movement of the plate cam 60 that moves the moving mechanism unit from the image forming position to the separated position. The support member is moved from the image forming position to a separated position separated from the photosensitive drum. Specifically, a rotation having a cam portion 73 provided at one end portion and a long hole 72 as an engaging portion that engages with the pin 63 of the plate cam 60 so as to rotate in conjunction with the plate cam 60. The movable lever member 71 is used. A cam portion 73 of the lever member 71 is formed so as to move the intermediate transfer belt 10 and its support member between the image forming position and the separation position as the lever member 71 rotates. In this case, the intermediate transfer belt 10 and the like are moved between the image forming position and the separation position by a simple operation of reciprocating the plate cam 60 in the intersecting direction (horizontal direction).

Further, according to the present embodiment (the printer of FIG. 8), the process cartridge (image forming unit) 54 including the above-described opposing components can be obtained by a simple operation of rotating the lever member 71 using the knob 71A of the lever member 71. Alternatively, the intermediate transfer belt 10 or the like can be moved between the image forming position and the separation position.
Note that the operation portion operated by the operator to rotate the lever member 71 may be formed in the cam portion 73 of the lever member in addition to the knob 71A of the lever member 71.
Further, the operation portion may be a protruding portion 60A in which the right end portion of the plate cam 60 is protruded to the swing unit (moving unit) 50 side.
Further, the lever member 71 may be configured to rotate in conjunction with the movement of opening the conveyance path of the swing unit (moving unit) 50. In this case, when the oscillating unit (moving unit) 50 is moved for maintenance of the apparatus, the process cartridge (image forming unit) 54 including the opposing component and the intermediate transfer are moved along with the movement. The belt 10 and the like can be moved from the image forming position to the separated position. Therefore, an individual operation for moving the process cartridge or the like to a separated position is not necessary.

  Further, according to the present embodiment (the printer of FIG. 8), the image forming frame 54F as a case member to which the above-described opposing components are attached is used as a movable rail member that can move in the direction of the rotation axis of the photosensitive drum. A slide rail R ′ is fixed. After the process cartridge (image forming unit) 54 including the above-described opposing components is moved to the separated position by the slide rail R ′ fixed to the image forming frame 54F, the image forming frame 54F is pulled out to process the process cartridge (image forming unit). ) 54 can be exposed. Therefore, maintenance / replacement of opposing components such as the charging device 3 and the developing devices 5A, 5B, 5C, and 5D is further facilitated.

  Although the case where a plurality of photosensitive drums are provided has been described in the above embodiment, the present invention is not limited to the number of photosensitive drums as long as an intermediate transfer member is used. A similar effect can be obtained. For example, the present invention sequentially forms toner images of each color (magenta, cyan, yellow, black) on a single photosensitive drum and primary transfer to an intermediate transfer member using a revolver type developing device or the like. The present invention can also be applied to such an image forming apparatus.

  In the above embodiment, the case where the image forming apparatus is a color printer has been described. However, the present invention can also be applied to other image forming apparatuses such as a FAX and a copying machine, and the same effect can be obtained. .

1 is a front view showing a schematic configuration of a printer according to an embodiment of the present invention. The enlarged view of the discharge stack part of the printer. The partial front view which shows the rocking | swiveling unit rock | fluctuated to the open state of the printer. The front view which shows schematic structure of the printer which concerns on other embodiment. The partial front view which shows the rocking | swiveling unit rock | fluctuated to the open state of the printer. Furthermore, the front view which shows schematic structure of the printer which concerns on other embodiment. FIG. 3 is a front view of the printer when the moving unit is moved to the open state of the printer. FIG. 3 is an explanatory diagram of a moving mechanism unit that moves an intermediate transfer unit and an image forming unit. FIG. 3 is a partial perspective view of the printer with the image forming frame pulled out. The front view of the conveyance belt unit of the state removed from the rocking | swiveling unit. 1 is an explanatory diagram of an image forming system using a printer according to an embodiment. FIG. 3 is an explanatory diagram illustrating a state of paper discharge in the printer of the present embodiment. Explanatory drawing of the paper discharge defect in the image forming apparatus which concerns on a prior art example.

Explanation of symbols

1A, 1B, 1C, 1D Photosensitive drum 2 Cleaning device 3 Charging device 4 Exposure device 5A, 5B, 5C, 5D Developing device 10 Intermediate transfer belt 11, 12, 13 Support roller 20 Primary transfer roller 30 Fixing device 30a Heating roller 40 Discharge stack part 41 Discharge port 42 Paper receiving surface 42a Inclined surface (main receiving surface)
50 Swing unit (moving unit)
50A Open / close support shaft 51 Intermediate transfer unit 52, 53, 54 Process cartridge (image forming unit)
54F Image forming frame 60 Plate cam 60A Protrusion 61 Long hole 62A Slope 62B Horizontal surface 63, 64 Pin 65 Support shaft 71 Lever member 71A Knob 72 Long hole (engagement part)
73 Cam part 100 Conveying belt 111, 112, 113 Support roller 120 Secondary transfer roller 250U Conveying belt unit F1, F2 Fan G1, G2 Switching guide member P Paper PG1, PG2, PG3, PG4 Refeeding conveying path R1, R2 , R3, R4 Conveying roller R Rail R 'Slide rail TC Toner cartridge W Heat insulation member

Claims (34)

A plurality of image carriers, image forming means for forming images of different colors on each image carrier, and a plurality of support members so as to pass through a primary transfer position facing each image carrier. An endless belt-shaped intermediate transfer member that is driven in this manner, a primary transfer unit that superimposes and transfers an image of each color formed on each image carrier on the intermediate transfer member, and a horizontal direction of the intermediate transfer member. At a secondary transfer position located on one end side, a secondary transfer unit that collectively transfers an image on the intermediate transfer body onto a recording medium, and an image on the recording medium that has passed the secondary transfer position are fixed. As described above, the fixing unit provided above the secondary transfer position, the secondary transfer position in the secondary transfer unit, and the recording medium are conveyed so as to pass upward through the fixing position in the fixing unit. Conveying means and recording medium positioned above the intermediate transfer member The recording medium that has passed through the only surface and the fixing means there is provided an image forming apparatus that includes a discharge portion having a discharge port for discharging to the recording medium receiving surface,
At least a part of the recording medium receiving surface of the discharge portion is inclined downward as it approaches the discharge port side, and its lowermost end is formed with an inclined surface lower than the discharge port,
The intermediate transfer member is stretched so that the intermediate transfer member extends in an inclined manner along the inclined surface of the discharge portion;
An image forming apparatus, wherein the plurality of image carriers are arranged so as to face a lower stretch portion of the intermediate transfer member. The image forming apparatus according to claim 1.
An image forming apparatus, wherein the image forming means is configured to form images of a plurality of different colors on at least one of the image carriers. The image forming apparatus according to claim 1 or 2,
The transport unit is configured using a transport belt member stretched by a plurality of support members so as to support and transport the recording medium along a transport path that passes through the secondary transfer position and toward the fixing position. An image forming apparatus. The image forming apparatus according to claim 3.
An image forming apparatus, wherein the conveying belt member is formed of a heat resistant material. The image forming apparatus according to claim 3 or 4,
An image forming apparatus comprising a moving unit capable of integrally moving the conveying belt member and a part of a conveying path forming member constituting the conveying unit so as to open the conveying path. The image forming apparatus according to claim 5.
The moving unit includes a conveying unit for forming a double-sided image that conveys the recording medium that has passed through the fixing unit so that the recording medium passes through the secondary transfer position with the front and back surfaces reversed. Image forming apparatus. The image forming apparatus according to claim 5 or 6,
When the moving unit is moved so as to open the conveying path, a conveying unit integrally configured to include the conveying belt member and a part of the conveying path forming member is connected to the moving unit. An image forming apparatus characterized by being detachable. The image forming apparatus according to claim 1 or 2,
Between the intermediate transfer member and the recording medium receiving surface of the discharge unit, a plurality of toner storage units that store different toners for forming images of the respective colors to be supplied to the image forming unit are provided in parallel.
An image forming apparatus comprising: a heat shielding unit for blocking heat transfer from the fixing unit to the toner containing unit between the toner containing unit and the fixing unit. The image forming apparatus according to claim 8.
An image forming apparatus comprising a heat insulating member as the heat shielding means. The image forming apparatus according to claim 8 or 9,
An image forming apparatus comprising: a ventilation unit for circulating air between the toner storage unit and the fixing unit as the heat shielding unit. The image forming apparatus according to claim 1 or 2,
Between the intermediate transfer member and the recording medium receiving surface of the discharge unit, a plurality of toner storage units that store different toners for forming images of the respective colors to be supplied to the image forming unit are provided in parallel.
An image forming apparatus, wherein the toner container is formed of a heat insulating material. The image forming apparatus according to claim 1 or 2,
Between the intermediate transfer member and the recording medium receiving surface of the discharge unit, a plurality of toner storage units that store different toners for forming images of the respective colors to be supplied to the image forming unit are provided in parallel.
A space is provided between the toner container and the intermediate transfer member so that the toner container and the intermediate transfer member do not interfere when the intermediate transfer member is moved away from the plurality of image carriers. An image forming apparatus comprising: The image forming apparatus according to any one of claims 8 to 12,
An image forming apparatus, wherein the toner container is detachable from a main body of the image forming apparatus. The image forming apparatus according to claim 1.
An image forming apparatus characterized in that an intermediate transfer unit integrally configured to include the intermediate transfer body and its support member is detachable from the image forming apparatus main body in a state of being separated from the image carrier. . The image forming apparatus according to any one of claims 1 to 14,
A process cartridge integrally configured to include the image carrier and at least one of a charging device, a developing device, and a cleaning device that cleans the surface of the image carrier, which form the image forming unit, forms an image. An image forming apparatus which is detachable from an apparatus main body. The image forming apparatus according to any one of claims 1 to 14,
A process cartridge integrally configured to include at least a charging device and a developing device constituting the image forming unit is separated from the image carrier, and is independent of the image carrier, with respect to the image forming apparatus main body. An image forming apparatus characterized by being detachable. The image forming apparatus according to any one of claims 1 to 16,
The intermediate transfer member is separated from the plurality of image carriers so that the intermediate transfer member is separated from the opposing components facing the image carrier among the components constituting the image forming unit. And the opposing component is configured to be movable,
An image forming apparatus, wherein only the image carrier is detachable from the apparatus main body in a state where the intermediate transfer member and the opposing component are separated from the image carrier. The image forming apparatus according to claim 1.
An image forming apparatus, wherein a process cartridge integrally configured to include the image carrier, the intermediate transfer member, and a supporting member thereof is detachable from an image forming apparatus main body. The image forming apparatus according to claim 15, 16 or 18.
An image forming apparatus, wherein the process cartridge is integrally provided for all or part of the plurality of image carriers. The image forming apparatus according to claim 1 or 2,
A moving mechanism for moving downward the opposing constituent elements facing the plurality of image carriers among the constituent elements constituting the image forming means;
The opposing component and the moving mechanism unit are arranged so that the opposing component and the moving mechanism unit do not interfere with each other when the opposing component is moved downward and separated from the plurality of image carriers. An image forming apparatus having a space therebetween. The image forming apparatus according to claim 20, wherein
A cam having a contact surface on which the lower end of the rail member supporting the opposing component contacts from above and movable in the direction intersecting with the contact direction of the lower end of the rail member. Composed of members,
An image forming method characterized in that a contact surface of the cam member is formed so that the opposing component can take an image forming position and a separated position separated from the image carrier by the movement of the cam member. apparatus. The image forming apparatus according to claim 21, wherein
The intermediate transfer member and its supporting member are separated from the image carrier from the image forming position in accordance with the movement of the cam member that moves the opposing component from the image forming position to the separated position. An image forming apparatus configured to be moved to a separated position. The image forming apparatus according to claim 22, wherein
The moving mechanism portion includes a rotatable lever member having a cam portion provided at one end portion and an engaging portion that engages with the cam member so as to rotate in conjunction with the cam member;
The cam portion of the lever member is formed so as to move the intermediate transfer member and the support member between the image forming position and the separation position as the lever member rotates. An image forming apparatus. 24. The image forming apparatus according to claim 23.
An image forming apparatus, wherein the lever member is provided with a knob for an operator to rotate the lever member. 24. The image forming apparatus according to claim 23.
An image forming apparatus, wherein the cam portion of the lever member is formed to be operable by an operator so as to rotate the lever member. 24. The image forming apparatus according to claim 23.
The transport unit is configured using a transport belt member stretched by a plurality of support members so as to support and transport the recording medium along a transport path that passes through the secondary transfer position and toward the fixing position. And
A moving unit capable of integrally moving the conveying belt member and a part of a conveying path forming member constituting the conveying means so as to open the conveying path;
An image forming apparatus, wherein the lever member is configured to rotate in conjunction with movement of the moving unit to open the transport path. 27. The image forming apparatus according to claim 20, wherein:
An image forming apparatus comprising: a case member to which the opposing component is attached; and a movable rail member fixed to the case member and movable in a direction of a rotation axis of the image carrier. A transport unit in the image forming apparatus according to claim 7,
It is comprised so that the said conveyance belt member and a part of said other conveyance member may be included,
A transport unit characterized in that it can be attached to and detached from the moving unit moved so as to open the transport path. The transport unit of claim 28,
While providing one roller of a pair of registration rollers as a part of the conveying member,
A transport unit comprising a cleaning means for cleaning the roller. The transport unit of claim 28,
A transport unit comprising a storage portion for storing the foreign matter removed by the cleaning means. An intermediate transfer unit in the image forming apparatus according to claim 14,
It is integrally configured to include the intermediate transfer member and its support member,
An intermediate transfer unit, wherein the intermediate transfer unit is detachable from the image forming apparatus main body in a state of being separated from the image carrier. A process cartridge in the image forming apparatus according to claim 15,
The image carrier is integrally configured to include at least one of a charging device, a developing device, and a cleaning device that cleans the surface of the image carrier that constitutes the image forming unit,
A process cartridge which is detachable from an image forming apparatus main body. A process cartridge in the image forming apparatus according to claim 16,
The image forming unit is integrally configured so as to include at least a charging device and a developing device,
A process cartridge, wherein the process cartridge is detachable from an image forming apparatus main body independently of the image carrier in a state of being separated from the image carrier. A process cartridge in the image forming apparatus according to claim 18,
The image carrier, the intermediate transfer body and the support member thereof are integrally configured,
A process cartridge which is detachable from an image forming apparatus main body.

Images