JP5167774B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus.

  In an image forming apparatus such as a printer or a copier using an electrophotographic system, the image carrier may need to be replaced. In order to facilitate replacement of the image carrier, generally, the image carrier and the components such as an exposure apparatus and a developer arranged around the image carrier are configured to be able to contact and separate from each other.

For example, Patent Document 1 discloses that the image exposure means is retracted in conjunction with a cartridge removal operation or a door opening operation that is performed in advance when a process cartridge is removed, and is positioned at a non-interference position when the process cartridge is removed. An image forming apparatus is described.
Japanese Patent Application Laid-Open No. 2004-228561 includes a mechanism that regulates the attachment or detachment of the photosensitive member or the imaging cartridge to the apparatus in accordance with the attachment or detachment state of the LED array for exposing the photosensitive member and forming a latent image. There is described an image forming apparatus in which an imaging cartridge cannot be attached or detached when it is not properly attached to the camera.
Further, in Patent Document 3, each exposure apparatus includes an LED array head, and each LED array head has a first position positioned at a certain distance from the photosensitive drum, and a first direction away from the photosensitive drum. The conveyor belt can be moved from the opposite position to the second position retracted from the opposite position, and the conveying belt can be moved from the opposite position to the opposite position facing the respective photosensitive drums. Each LED array head is positioned at the second position in conjunction with the retracting operation of the transport belt when the transport belt is moved to the retracted position, and is returned to the transport belt when the transport belt is moved to the facing position. An image forming apparatus that is linked to the first position is described.

Japanese Patent Laid-Open No. 04-212973 JP 2000-293085 A JP 2001-175046 A

  Incidentally, components such as an exposure device, a developing device, and a transfer belt are disposed around the image carrier. In order to prevent these components from being damaged during the image carrier replacement work, simply setting the order of attaching and detaching each component and interlocking each component will prevent failure due to incorrect operation. I can't.

  The present invention can prevent erroneous operation of the image carrier replacement operation by the operation unit for retracting the components arranged around the image carrier, and can prevent erroneous operation of the operation unit during the image carrier replacement operation. An object is to provide an image forming apparatus.

According to the first aspect of the present invention, there is provided an image holding member that holds an image and is detachably disposed, and an exposure device that is disposed around the image holding member and exposes the image holding member to form a latent image. A developing unit disposed around the image carrier and developing the latent image formed by the exposure device; and an image disposed in contact with the image carrier and developed by the developing unit ; or the image A transfer belt that conveys the recording material to which the image is transferred and transfers the image to the recording material, a cover member that moves between a state where at least the image carrier and the exposure device are covered, and a state where the cover is not covered, and the cover A lever that moves between a position that presses a member and a position that does not press, a transfer belt contact position at which the transfer belt contacts the image carrier, and a transfer belt separation position at which the transfer belt is separated from the image carrier. the operation of the lever The transfer belt and a transfer belt moving means for moving operation, an exposure device proximity position where the exposure apparatus is close to the image carrier, with the exposure apparatus spaced position away from the image carrier Te, the cover said cover when provided with an exposure device moving means for moving operating the exposure apparatus by the operation member, and a locking mechanism for locking the movement of said lever, said lever, said transfer belt is in the transfer belt contact position located in a position to press the member, the image when the transfer belt is positioned at a position not holding the cover member when in the transfer belt separation position, said cover member, said exposure device is in the exposure device proximity position disposed in a position covering the retaining member, the locking device with disposed in a position that does not cover the image bearing member when the exposure apparatus is in said exposure device separation position An image forming apparatus characterized by locking said lever by operating the.

According to a second aspect of the present invention, there is provided an image carrier that holds an image and is detachably disposed, and an exposure device that is disposed around the image carrier and exposes the image carrier to form a latent image. A developing device disposed around the image carrier and developing the latent image formed by the exposure device; and an image placed in contact with the image carrier and developed by the developing device; or A transfer belt that conveys the recording material onto which the image is transferred and transfers the image onto the recording material; a transfer belt contact position where the transfer belt contacts the image carrier; and a transfer belt separation that is spaced apart from the image carrier. A transfer belt contacting / separating means for moving the transfer belt by an operation of the first operation unit between the position, an exposure apparatus proximity position where the exposure apparatus is close to the image holding body, and from the image holding body The distance between the exposure apparatus and the separated position An exposure device moving means for moving operating the exposure apparatus by the operation of the second operating unit, when the exposure apparatus is in said exposure device separation position, and a locking mechanism for locking the first operation unit, said developing comprising a developing unit close position vessel is close to the image carrier, between the developing device separation position where the developing device is disengaged from said image carrier, a developing device moving means for moving the developing unit, the The first operation unit prohibits a user operation on the second operation unit when the transfer belt is at the transfer belt contact position, and the second operation unit is configured so that the exposure apparatus performs the exposure. Arranged at a position that hinders the user from attaching and detaching the image holding member when in the apparatus proximity position, and arranged at a position that allows the image holding member to be attached and detached when the exposure apparatus is at the exposure apparatus separation position. the developing device contact and separation The stage is interlocked with the exposure apparatus contact / separation means, and when the second operation unit is operated so that the exposure apparatus is positioned in the proximity of the exposure apparatus, the developer contact / separation means causes the developer to move the developer. is moved to the close position, when it is operated so that the exposure device separation position the developing device moving means is images forming apparatus you and moving the developing device separation position.

The invention according to claim 3 includes an image carrier, an exposure device that exposes the image carrier to form a latent image, and a developer that develops the latent image formed by the exposure device, A plurality of image forming units arranged at regular intervals, and an image formed by the plurality of image forming units, which are arranged opposite to the plurality of image forming units , or the image is transferred A transfer belt that conveys the recording material to be transferred and transfers the image onto the recording material, and a cover member that moves between a state in which at least the image carrier and the exposure apparatus of the image forming unit are covered and a state in which the image forming unit is not covered , a lever that moves between a position which does not hold a position for pressing the cover member, and the transfer belt contact position where the transfer belt comes into contact with the image carrier of the plurality of image forming units, apart from the image carrier Between the transfer belt separation position that, the image carrier of the transfer belt moving means and the exposure apparatus the plurality of image forming units of the plurality of image forming units for moving operating the transfer belt by the operation of said lever An exposure apparatus contacting / separating means for moving the exposure apparatus by operating the cover member between an exposure apparatus proximity position close to the body and an exposure apparatus separation position separated from the image carrier, and movement of the lever and a locking mechanism for locking the said lever, said cover when said transfer belt when in said transfer belt contact position, located in a position to press the cover member, to which the transfer belt is in the transfer belt separation position located at a position not holding member, said cover member, at least two of said image forming units of the plurality of image forming units The exposure device is disposed at a position that covers the image carrier when in the exposure apparatus proximity position, together with the exposure device is disposed at a position not covering the image carrier when in the exposure device separation position of An image forming apparatus that operates the lock mechanism to lock the lever .

The invention according to claim 4 includes an image carrier, an exposure device that exposes the image carrier to form a latent image, and a developer that develops the latent image formed by the exposure device, A plurality of image forming units arranged at regular intervals, and an image formed by the plurality of image forming units, which are arranged opposite to the plurality of image forming units, or the image is transferred A transfer belt that conveys the recording material to be transferred and transfers the image onto the recording material, a transfer belt contact position where the transfer belt contacts the image carrier of the plurality of image forming units, and a distance from the image carrier. A transfer belt contacting / separating means for moving the transfer belt by operating the first operation unit between the transfer belt separating positions and the exposure device of the plurality of image forming units. The statue An exposure apparatus contact / separation means for moving and operating the exposure apparatus by an operation of a second operation unit between an exposure apparatus proximity position close to the holder and an exposure apparatus separation position separated from the image carrier; A locking mechanism that locks the first operation unit when the exposure apparatus is at the exposure apparatus separation position ; and a developer proximity position where the developing device of the image forming unit is close to the image carrier of the image forming unit. And a developing device contacting / separating means for moving the developing device between the developer holding position separated from the image carrier, and the exposure of at least two of the plurality of image forming units. and a interlocking means for interlocking the operation of the developing device moving means for said developing unit of the image forming unit of operation and the two or more of the exposure apparatus moving means to the device, wherein the The operation unit prohibits a user operation on the second operation unit when the transfer belt is at the transfer belt contact position, and the second operation unit includes at least two of the plurality of image forming units. When the exposure apparatus of the image forming unit is located at a position close to the exposure apparatus, the exposure apparatus is disposed at a position that inhibits the user from attaching or detaching the image carrier of the two or more image forming units. The second operation unit is disposed at a position where the image holding member can be attached / detached when the apparatus is in the apparatus separation position, and the exposure apparatus of the two or more image forming units is positioned near the exposure apparatus. When operated, the interlocking means interlocks the developing device contacting / separating means with the exposure device contacting / separating means to move the developing devices of the two or more image forming units to the developing device proximity position. Are allowed, it is images forming apparatus you and moving the developing device separation position to be engineered to be the exposure device separation position.

According to the first aspect of the present invention, the user can move the exposure device close to or away from the image holding member by operating the cover member without being particularly conscious, and the transfer belt is in contact with the transfer belt. If the lever is operated, the opening of the cover member can be prohibited, and the lever and the cover member can be prevented from moving to the transfer belt contact position due to the lever being erroneously operated during the attaching / detaching operation of the image carrier. It is possible to prevent a user's erroneous operation with respect to.
According to claim 2 of the present invention, only by operating the second operating portion, it can be close to or away from the developing unit and the exposure apparatus relative to the image carrier.
According to the third aspect of the present invention, the user can move the exposure device close to or away from the image holding member by operating the cover member without being particularly conscious, and the transfer belt is in contact with the transfer belt. If the lever is operated, the opening of the cover member can be prohibited, and the lever and the cover member can be prevented from moving to the transfer belt contact position due to the lever being erroneously operated during the attaching / detaching operation of the image carrier. It is possible to prevent a user's erroneous operation with respect to.
According to the fourth aspect of the present invention, the exposure apparatus and the developing device can be brought close to or separated from the image carrier with respect to the two or more image forming units only by operating the second operation unit.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 is a diagram illustrating an example of the overall configuration of an image forming apparatus 1 to which the exemplary embodiment is applied.
An image forming apparatus 1 shown in FIG. 1 is a so-called tandem type multifunction machine having a copy function and a printer function, and an image forming process unit 10 that forms an image corresponding to image data of each color, and the entire image forming apparatus 1. And a control unit 30 for controlling the operation. The image forming apparatus 1 is connected to an external device such as a personal computer (PC) 3 or an image reading device 4, for example, and an image processing unit 35 that performs predetermined image processing on image data received from these devices, And a main power supply 70 that supplies power to each unit.

The image forming process section 10 includes a plurality of image forming units 11Y, 11M, 11C, and 11K (hereinafter collectively referred to simply as “image forming units 11”) that are arranged in parallel at regular intervals. It has been.
Each image forming unit 11 includes a photosensitive drum 12 as an example of an image holding member that forms an electrostatic latent image and holds a toner image, and a charger that uniformly charges the surface of the photosensitive drum 12 with a predetermined potential. 13. Each image forming unit 11 is formed on the photosensitive drum 12 and an LED print head (LPH) 14 as an example of an exposure device that exposes the photosensitive drum 12 charged by the charger 13 based on image data. A developing unit 15 for developing the electrostatic latent image and a cleaner 16 for cleaning the surface of the photosensitive drum 12 after the transfer are provided.
Here, each image forming unit 11 is configured in substantially the same manner except for the toner stored in the developing device 15. Each image forming unit 11 forms yellow (Y), magenta (M), cyan (C), and black (K) toner images.

  The image forming process unit 10 includes an intermediate transfer belt 20 as an example of a transfer belt onto which the color toner images formed on the photosensitive drums 12 of the image forming units 11 are transferred, and the color toners formed by the image forming units 11. A primary transfer roll 21 that sequentially transfers (primary transfer) images to the intermediate transfer belt 20 is provided. In addition, the image forming process unit 10 includes a secondary transfer roll 22 that collectively transfers (secondary transfer) the superimposed toner image transferred onto the intermediate transfer belt 20 onto a sheet that is a recording medium (recording paper), and a secondary transfer. And a fixing device 60 for fixing the formed image on the paper.

  Here, in each image forming unit 11, the photosensitive drum 12 is configured to be detachable from the image forming apparatus 1 and can be replaced according to the life of the photosensitive drum 12. In each image forming unit 11, the photosensitive drum 12, the charger 13, and the cleaner 16 are configured as an integrated module (hereinafter referred to as “photosensitive module MOD”). It is good also as an exchangeable structure according to. Further, a configuration including the photosensitive drum 12 and the charger 13 may be employed. In other words, as long as the photosensitive drum 12 includes a shorter life than other components, it may be configured in combination with any component. However, the photoconductor module MOD of the present embodiment is premised on a configuration separate from the LPH 14 and the developing device 15.

The LPH 14 has a predetermined position (hereinafter also referred to as an “exposure position”) that exposes the photosensitive drum 12 that is set at the time of image formation by a contact / retraction mechanism that will be described later. It is configured to be able to contact and separate from a position (hereinafter also referred to as “LPH separation position”) separated from the photosensitive drum 12 set at the time of attachment / detachment.
The developing unit 15 is configured to be able to contact and separate from the photosensitive drum 12 in conjunction with the contacting and separating operation of the LPH 14. That is, when the LPH 14 is set at the exposure position, the developing unit 15 is disposed at a predetermined position (hereinafter also referred to as “development position”) for developing the electrostatic latent image formed on the photosensitive drum 12. The Further, when the LPH 14 is set at the LPH separation position, the LPH 14 is disposed at a position separated from the photosensitive drum 12 (hereinafter also referred to as “developing device separation position”).

  In such an image forming apparatus 1, image data input from the PC 3 or the image reading device 4 is subjected to image processing by the image processing unit 35 and supplied to each image forming unit 11 via an interface (not shown). . For example, in the black (K) image forming unit 11K, the photosensitive drum 12 is uniformly charged at a predetermined potential by the charger 13 while rotating in the arrow A direction, and the image transmitted from the image processing unit 35 is transmitted. The exposure is performed by the LPH 14 that emits light based on the data. Thereby, an electrostatic latent image related to a black (K) color image is formed on the photosensitive drum 12. The electrostatic latent image formed on the photosensitive drum 12 is developed by the developing device 15, and a black (K) toner image is formed on the photosensitive drum 12. Similarly, yellow (Y), magenta (M), and cyan (C) toner images are formed in the image forming units 11Y, 11M, and 11C, respectively.

  The respective color toner images formed by the respective image forming units 11 are sequentially electrostatically attracted by the primary transfer roll 21 onto the intermediate transfer belt 20 moving in the direction of arrow B to form a composite toner image in which the respective color toners are superimposed. Is done. The synthetic toner image on the intermediate transfer belt 20 is conveyed to a region (secondary transfer portion T) where the secondary transfer roll 22 is disposed as the intermediate transfer belt 20 moves. When the composite toner image is conveyed to the secondary transfer unit T, the sheet is supplied from the sheet holding unit 40 to the secondary transfer unit T in accordance with the timing at which the toner image is conveyed to the secondary transfer unit T. The composite toner image is collectively electrostatically transferred onto the conveyed paper by the transfer electric field formed by the secondary transfer roll 22 in the secondary transfer portion T.

Thereafter, the sheet on which the synthetic toner image has been electrostatically transferred is peeled off from the intermediate transfer belt 20 and conveyed to the fixing device 60. The synthesized toner image on the paper conveyed to the fixing device 60 is fixed on the paper by the fixing device 60 by a fixing process using heat and pressure. Then, the sheet on which the fixed image is formed is conveyed to a paper discharge stacking unit 45 provided in the discharge unit of the image forming apparatus 1.
On the other hand, the toner (transfer residual toner) adhering to the intermediate transfer belt 20 after the secondary transfer is removed from the surface of the intermediate transfer belt 20 by the belt cleaner 25 after the completion of the secondary transfer to prepare for the next image forming cycle. .
In this way, image formation in the image forming apparatus 1 is repeatedly executed for the number of printed sheets.

(Configuration of LED print head (LPH))
Next, the configuration of the LED print head (LPH) 14 will be described.
FIG. 2 is a cross-sectional configuration diagram showing the configuration of the LPH 14.
The LPH 14 is disposed below the photosensitive drum 12 and exposes the photosensitive drum 12 from below. As shown in FIG. 2, the LPH 14 is a drive circuit that drives a housing 61 as a support, an LED array 63 that is a light source that exposes the photosensitive drum 12 to form a latent image, and the LED array 63 and the LED array 63. And the like, a rod lens array 64 that images light from the LED array 63 on the surface of the photosensitive drum 12, a holder 65 that supports the rod lens array 64 and shields the LED array 63 from the outside, and a housing A leaf spring 66 is provided to pressurize 61 toward the rod lens array 64.

The housing 61 is formed of a metal block such as aluminum or SUS or a sheet metal, and supports the LED circuit board 62. The holder 65 supports the housing 61 and the rod lens array 64, and is set so that the light emitting point of the LED array 63 and the focal plane of the rod lens array 64 coincide. Further, the holder 65 is configured to seal the LED array 63. Thus, a configuration in which dust is difficult to adhere to the LED array 63 from the outside is realized. On the other hand, the leaf spring 66 presses the LED circuit board 62 in the direction of the rod lens array 64 via the housing 61 so as to maintain the positional relationship between the LED array 63 and the rod lens array 64.
The LPH 14 configured in this manner is configured to be movable in the optical axis direction of the rod lens array 64 by an adjusting screw (not shown), and the image formation position (focal plane) of the rod lens array 64 is on the surface of the photosensitive drum 12. Adjusted to be located at

(Developer configuration)
Subsequently, the configuration of the developing device 15 will be described.
FIG. 3 is a cross-sectional configuration diagram showing the configuration of the developing device 15.
As shown in FIG. 3, the developing device 15 includes a developer holding container for containing the developer, a support container 51 as a casing of the developing device 15, a developing sleeve 52, and a developing magnet 53 that attracts the developing agent 52 to the developing sleeve 52. I have. The developing device 15 includes a trimmer 54 that regulates the layer thickness (application amount) of the developer, a developer supply screw member 55 that circulates and moves the developer in the longitudinal direction of the developing device 15 while stirring the developer, and a developer stirring screw member. 56.

The support container 51 has an opening toward the photosensitive drum 12, and a developer containing portion that contains a developer in which toner and a carrier that is magnetic particles are mixed is provided inside. The developer accommodating portion is divided into a first developer accommodating portion 51b and a second developer accommodating portion 51c by an accommodating portion wall 51a provided in the longitudinal direction of the developing device 15.
A developer supply screw member 55 is disposed in the first developer accommodating portion 51b, and a developer stirring screw member 56 is disposed in the second developer accommodating portion 51c. The accommodating portion walls 51a are not provided at both ends in the longitudinal direction of the developing device 15, and the first developer accommodating portion 51b and the second developer accommodating portion 51c are connected at both ends, and the developer. Circulate mutually.

The developing sleeve 52 is made of a nonmagnetic material such as aluminum or SUS, and is rotated in the direction of arrow C by a driving unit (not shown). The developing sleeve 52 is applied with a developing bias consisting of a DC voltage from a power source (not shown) or a developing bias in which a DC voltage is superimposed on an AC voltage, thereby forming a developing electric field between the developing sleeve 52 and the photosensitive drum 12.
A developing magnet 53 is included in the developing sleeve 52. The developing sleeve 52 adsorbs the developer in the first developer accommodating portion 51 b by the magnetic force of the developing magnet 53, and then the layer thickness (application amount) of the developer is regulated by the trimmer 54. Then, the developer is conveyed to a position facing the photosensitive drum 12 according to the rotation of the developing sleeve 52, and the developer is brought into contact with the photosensitive drum 12 under a developing electric field, so that an electrostatic latent image on the photosensitive drum 12 is formed. develop. The developer that has been developed is transported into the support container 51 and collected in the first developer container 51b.
The trimmer 54 is made of a nonmagnetic material or a magnetic material, and regulates the layer thickness of the developer held on the developing sleeve 52 together with the magnetic pole inside the developing magnet 53 to a predetermined amount. As a result, a predetermined amount of developer is uniformly supplied to the photosensitive drum 12 along the axial direction of the developing sleeve 52.

Both the developer supply screw member 55 of the first developer accommodating portion 51b and the developer agitating screw member 56 of the second developer accommodating portion 51c have a structure in which a helical screw is provided around the rotation shaft. ing. The developer supply screw member 55 and the developer agitating screw member 56 are rotated in opposite directions by driving means (not shown), and convey the toner and the carrier in the opposite directions while stirring.
On the other hand, the first developer accommodating portion 51 b and the second developer accommodating portion 51 c are connected at both ends of the developing device 15. Therefore, the developer circulates between the first developer accommodating portion 51b and the second developer accommodating portion 51c by the developer supply screw member 55 and the developer agitating screw member 56. As a result, the developer separated from the developing sleeve 52 and collected in the first developer accommodating portion 51b is conveyed to the second developer accommodating portion 51c by the developer supply screw member 55 and the developer agitating screw member 56. Is done.

The support container 51 is connected to a toner supply path (not shown) for supplying toner to the second developer accommodating portion 51c. The toner supply path is connected to a toner container (not shown) disposed above the developing unit 15, and the toner is dropped from the toner container in which each color toner is stored through the toner supply path. Each color toner is supplied to the second developer accommodating portion 51c.
When new toner is supplied from the toner container to the developer in the second developer accommodating portion 51c, the toner supply amount is adjusted so that the toner concentration is controlled within a predetermined range by a toner concentration detection sensor (not shown). Is done. Then, the developer to which the toner has been newly supplied is sufficiently stirred and mixed by the developer stirring screw member 56 with the toner and the magnetic carrier, and the first development by the developer supplying screw member 55 and the developer stirring screw member 56 is performed. By the circulation between the developer container 51b and the second developer container 51c, it is conveyed again to the first developer container 51b. Then, from the first developer accommodating portion 51b, the developer whose toner density is adjusted to a predetermined range and sufficiently charged to the toner is supplied to the developing sleeve 52. In this way, the developer is circulated.

Further, the developing device 15 is provided with a seal member 57 on a support container side wall 51 d at a position facing the photosensitive drum 12 and below the developing sleeve 52.
As shown in FIG. 3, the seal member 57 is disposed so that one end 57 a is fixed to the support container side wall 51 d and the other end 57 b is directed downstream of the rotation direction arrow A of the photosensitive drum 12. Is done. The end 57b is configured to contact the surface of the photosensitive drum 12.

Accordingly, the seal member 57 shields the space between the developing sleeve 52 and the LPH 14 along the axial direction of the photosensitive drum 12 in a state where the developing device 15 is set at the developing position. Then, the developer scattered or dropped from the developing sleeve 52 is prevented from adhering to the light emitting surface of the rod lens array 64 (see FIG. 2) of the LPH 14 disposed below the developing sleeve 52. Therefore, it is difficult for the light emitting surface of the rod lens array 64 to be stained.
As the sealing member 57 here, a film-like material that hardly causes wear or damage on the surface of the photosensitive drum 12 and that is easy to uniformly contact with the surface of the photosensitive drum 12, such as a polyurethane film, is used. It is done. Further, the thickness, dimension, and the like of the seal member 57 are appropriately selected from such a viewpoint.

(Intermediate transfer belt contact / separation operation)
4 is a diagram showing a state in which the cover 91 is attached to the four image forming units 11, and FIG. 5 is a diagram showing a main part where the transfer belt retract handle 71 fixes the cover 91. 6 is a diagram illustrating a state in which the transfer belt retract handle 71 is operated to release the cover 91 from being fixed.
As shown in FIG. 4, the image forming apparatus 1 is provided with a second operation unit and a cover 91 as an example of a cover member for the purpose of preventing an erroneous operation by a user and intrusion of dust and the like, and four image forming units 11. Is covered. The upper left portion of the cover 91 is pressed by a transfer belt retract handle 71 as an example of a first operation unit and a flange 73 as an example of a first operation unit. Further, the cover 91 is configured such that a hinge 92 is attached to the lower side and the upper side is opened. The transfer belt retract handle 71 is rotated in the direction of the arrow shown in FIGS. 4 and 6 and functions as a lever that receives an operation by the user.

  When the transfer belt retract handle 71 is in the first position shown in FIG. 4, as shown in FIG. 5, the flange 73 presses the upper left end portion of the cover 91 to prohibit the user from opening the cover 91. Yes. The cover 91 covers the four image forming units 11 (see FIG. 1), and the cover 91 is arranged at a position that hinders the user from attaching or detaching the photosensitive drum 12 (see FIG. 1). That is, the user cannot access the photosensitive drum 12. At this time, the intermediate transfer belt 20 is at a position (transfer belt contact position) in contact with the photosensitive drum 12.

As shown in FIG. 6, when the transfer belt retract handle 71 is rotated to the second position shown in FIG. 6, the flange 73 does not hold the cover 91, so the user can open the cover 91. it can.
When the cover 91 is opened, the cover 91 moves downward in the figure with the hinge 92 as the center of rotation, and retreats to a position that does not hinder the attachment / detachment work of the photosensitive drum 12 of the image forming unit 11. Then, four image forming units 11 appear (see FIG. 8). At this time, in the image forming apparatus 1, the intermediate transfer belt 20 moves to a position separated from the photosensitive drum 12 (transfer belt separation position).

  FIG. 7 is a diagram for explaining a transfer belt contact / separation mechanism that operates the transfer belt retract handle 71 to contact / separate the photosensitive drum 12 with respect to the intermediate transfer belt 20. 7A is a diagram illustrating a state in which the intermediate transfer belt 20 is close to the photosensitive drum 12 at the first position illustrated in FIG. 4, and FIG. 7B is a diagram illustrating the intermediate position at the second position illustrated in FIG. 2 is a diagram illustrating a state in which a transfer belt 20 is separated from a photosensitive drum 12. FIG.

(Configuration of transfer belt contacting / separating means)
The transfer belt retract handle 71 has an elliptical cam 152 attached to the end of a shaft 72 (see FIG. 9). The cam 152 rotates in accordance with the rotation operation of the transfer belt retract handle 71.
As shown in FIG. 7A, the cam 152 is in contact with the cam receiver 153 at the short axis side. The cam receiver 153 is fixed to a slider 151 that slides in the horizontal direction in the figure (the direction of the arrow in the figure). The slider 151 always receives a tensile force from an urging spring 154 attached to the right end, and is pulled in the right direction in the figure, so that the cam 152 and the cam receiver 153 are in contact with each other.

Four substantially L-shaped moving direction conversion members 155 are attached to the slider 151 corresponding to the four primary transfer rolls 21. One end of the moving direction conversion member 155 is attached to the slider 151 in a rotatable state, and a fulcrum 156 provided at a central bent portion is attached to a support (not shown) of the intermediate transfer belt 20 in a rotatable state. The other end is attached so that the primary transfer roll 21 can rotate. Further, the moving direction converting member 155 has a spring 157 attached in the vicinity of one end attached to the slider 151, and always receives a tensile force to absorb variations in the position of the primary transfer roll 21. That is, by attaching the spring 157 to each moving direction conversion member 155, each of the primary transfer rolls 21 attached to the other end is reliably pressed against the intermediate transfer belt 20. The biasing spring 154 pulls the slider 151 with a force larger than the pulling force applied to the slider 151 by the four springs 157, so that the cam 152 and the cam receiver 153 are kept in contact with each other.
When the transfer belt retract handle 71 is in the first position shown in FIG. 4, the intermediate transfer belt 20 is moved by the tension roll 160 and the idler roll 161 receiving the pressing force from the spring 158 as shown in FIG. It is in a state with tension. That is, the tension roll 160 and the idler roll 161 push the intermediate transfer belt 20 in the direction of the photosensitive drum 12, and the intermediate transfer belt 20 is in a position (transfer belt contact position) in contact with the photosensitive drum 12.

(Contact / separation operation of transfer belt contact / separation means)
When the transfer belt retract handle 71 is rotated, the cam 152 fixed to the shaft of the transfer belt retract handle 71 pushes the cam receiver 153 while rotating to move the slider 151 in the left direction in the figure. When the transfer belt retract handle 71 is at the second position shown in FIG. 6, the surface on the long axis side of the cam 152 pushes the cam receiver 153 (see FIG. 7B).
When one end of the moving direction conversion member 155 is moved in the left direction as the slider 151 moves in the left direction, the central fulcrum 156 acts as the center of rotation and is attached to the other end of the moving direction conversion member 155. The primary transfer roll 21 and idler roll 161 thus obtained are rotated and moved upward. With the rotational movement of the idler roll 161 upward, the intermediate transfer belt 20 loses tension, and the intermediate transfer belt 20 moves obliquely upward by the force of the tension roll 160. At this time, the distance that the intermediate transfer belt 20 is separated from the photosensitive member is Y is the largest and K is the smallest. As a result, the intermediate transfer belt 20 moves to a position separated from the photosensitive drum 12 (transfer belt separation position).

  If the operation opposite to that described above is performed, that is, if the transfer belt retract handle 71 is returned to the first position shown in FIG. 4, the intermediate transfer belt 20 is in contact with the photosensitive drum 12 (transfer belt contact position). Return to. That is, the transfer belt retract handle 71, the cam 152, the cam receiver 153, the slider 151, the moving direction conversion member 155, the biasing spring 154, and the like function as a transfer belt contacting / separating unit.

(Transfer belt retract handle lock)
As described above, when the transfer belt retract handle 71 is in the second position shown in FIG. 6, the cover 91 can be opened.
FIG. 8 is a diagram showing a state when the cover 91 is opened, and FIG. 9 is a diagram showing a state when the transfer belt retract handle 71 is in the cover release position.
As shown in FIG. 8, a protrusion 93 is formed on the inner surface of the cover 91. When the cover 91 is closed (the state shown in FIG. 4), the protrusion 93 is inserted into a protrusion insertion hole 94 formed near the transfer belt retract handle 71.
Also, four levers 225 are attached to the inner side surface of the cover 91 corresponding to the four image forming units 11, and the lever 225 is rotated in conjunction with the opening / closing operation of the cover 91.

When the transfer belt retract handle 71 is in the second position shown in FIG. 6 and the cover 91 is opened, the protrusion 93 formed integrally with the cover 91 is taken out from the protrusion insertion hole 94.
As shown in FIG. 9, in the lock mechanism 80 provided adjacent to the transfer belt retract handle 71, the protrusion 93 is separated from the protrusion receiver 82 against which the protrusion 93 (see FIG. 8) is abutted. . Due to the restoring force of the torsion spring 83, the lever lock 81 rotates about the fulcrum 84 and the protrusion receiver 82 rotates upward. Then, the lever lock 81 enters the gap inside the transfer belt retract handle 71. Therefore, the transfer belt retract handle 71 cannot be rotated.

(Developer contact / separation operation)
Next, the separation operation of the developing device 15 will be outlined.
As described above, the developing device 15 is brought into contact with and separated from the photosensitive drum 12 in conjunction with the contact and separation operation of the LPH 14 when the photosensitive drum 12 is attached and detached, for example. That is, when the photosensitive drum 12 is mounted at a predetermined position in the image forming apparatus 1, the LPH 14 is disposed at a position close to the photosensitive drum 12 (exposure apparatus proximity position). In conjunction with this, the developing unit 15 is disposed at a position where the electrostatic latent image on the photosensitive drum 12 can be developed (a position adjacent to the developing unit). On the contrary, for example, when the photosensitive drum 12 is removed from the image forming apparatus 1, the LPH 14 is moved to a position separated from the photosensitive drum 12 (exposure apparatus separation position). The developing device 15 is moved to a position (developing device separation position) that is separated from the photosensitive drum 12.

The developing device 15 is performed in conjunction with the contact / separation operation (retraction operation) of the LPH 14. Below, it explains in full detail using a figure.
FIG. 10 is a view showing a state in which the LPH 14 is set at the exposure apparatus proximity position, and FIG. 11 is a view showing a state in which the LPH 14 is set at the LPH separation position.
In a state where the LPH 14 shown in FIG. 10 is set at the exposure apparatus proximity position, positioning is performed so that the LPH 14 is set at a predetermined position with respect to the photosensitive drum 12. 10 and 11, the left side of the drawing is the front side of the image forming apparatus 1 and the side where the photosensitive drum 12 is attached and detached. Further, the right side of the drawing is the back side of the image forming apparatus 1 and the side from which the drive from the rotationally driven drive motor is transmitted to the photosensitive drum 12 and the like. In the present specification, for members having similar functions, “F” is used for the number of the member arranged on the front side, and “R” is used for the number of the member arranged on the back side. "Is used.

As shown in FIG. 10, the housing 61 of the LPH 14 has a first protrusion that determines the position of the rod lens array 64 in the LPH 14 in the optical axis direction (this is defined as the “Y direction”) as the LPH 14 positioning mechanism. The positions of the members 251F, 251R and the LPH 14 in the axial direction of the photosensitive drum 12 (this is defined as “Z direction”) and the direction orthogonal to both the Y direction and the Z direction (this is referred to as “X direction”). The second projecting members 252F and 252R that simultaneously determine the position of The housing 61 is urged in a direction (Z direction) from the back side toward the XZ direction support member 123F side by a pressing spring 212 provided on the main body frame FRA.
On the other hand, the LPH 14 side first projecting members 251F and 251R are abutted on the photoconductor module MOD that supports the photoconductor drum 12 coaxially with the rotation shaft 121 of the photoconductor drum 12 as a positioning mechanism of the LPH14. An XZ direction support member that simultaneously sets the X direction position and the Z direction position of the LPH 14 by supporting the Y direction support members 122F and 122R that set the Y direction position of the LPH 14 and the second projecting members 252F and 252R on the LPH 14 side. 123F and 123R are arranged.

  Then, when the image forming apparatus 1 performs the image forming operation, the first projecting members 251F and 251R on the LPH 14 side are respectively in the Y-direction support member 122F in a state where the LPH 14 in FIG. , 122R. Thereby, the position in the Y direction of the LPH 14 is set. Further, the second projecting members 252F and 252R on the LPH 14 side are supported by the XZ direction support members 123F and 123R, respectively. Thereby, the X-direction position and the Z-direction position of the LPH 14 are set simultaneously.

Further, in addition to the positioning mechanism of the LPH 14 described above, the image forming apparatus 1 is provided with a contact / separation mechanism (retract mechanism) as an example of an exposure device contact / separation unit with respect to the LPH 14.
That is, as shown in FIG. 10, as a retract mechanism for moving the LPH 14 to the exposure apparatus separation position, one end is rotatably supported by the housing 61 of the LPH 14 and the other end is rotatably supported by the retract member 220. 260, a retract member 220 that changes the inclination angle of the cam 260 by sliding in the lateral direction, a stage 221 that guides the slide movement of the retract member 220, a lever 225 that slides the retract member 220, and a vertical movement of the LPH 14 Are provided with a guide member 240 and a stopper 230 for restricting the movement of the LPH 14 in the front side direction.

  In addition, a vertical movement member 270 is integrally attached to the cam 260. The vertical movement member 270 is configured to move in the vertical direction according to the inclination angle of the cam 260. When the LPH 14 is set at the exposure apparatus proximity position, the vertical movement member 270 is set at the lower position. As shown in FIG. 11, in the state where the LPH 14 is set at the exposure apparatus separation position, the vertical movement member 270 is set at the upper position. As the vertical movement member 270 moves in the vertical direction, a rotation operation about the position Q related to the developing device 15 described above is performed (see FIG. 13 described later). Note that the rotation operation (developer contact / separation operation) of the developing device 15 by the vertical movement of the vertical moving member 270 will be described in detail later.

  In this LPH 14 retract mechanism, the retract member 220 is set to the left position in FIG. 10 by the lever 225 in a state where the LPH 14 shown in FIG. As a result, the cam 260 has an inclination angle of about 90 ° with respect to the retract member 220, and pushes up the LPH 14 toward the photosensitive drum 12. Corresponding to the inclination angle of the cam 260, the vertically moving member 270 integrally attached to the cam 260 is set at a lower position.

On the other hand, when the LPH 14 in FIG. 11 is set to the exposure apparatus separation position, the lever 225 is tilted to the left, so that the retract member 220 supported by the stage 221 moves from the front side to the back side (right direction in FIG. 11). ) To slide. When the retract member 220 is slid from the front side to the back side, the connecting portion of the cam 260 with the retract member 220 moves to the back side, and the cam 260 is inclined to the left in FIG. The LPH 14 is separated from the photosensitive drum 12 downward.
At that time, the first projecting members 251F and 251R and the second projecting members 252F and 252R are detached from the Y-direction support members 122F and 122R and the XZ-direction support members 123F and 123R, respectively. In conjunction with the tilting of the cam 260, the vertically moving member 270 that is integrally attached to the cam 260 is set to the upper position.

FIG. 12 is an enlarged view around the up and down moving member 270.
In FIG. 12, a cam 260 is formed with a direction changing rotary shaft support portion 260a at the rear upper portion, and is supported so as to be rotatable about the direction changing rotary shaft 18 with respect to an outer frame (not shown). ing. A contact / separation member connecting portion 260b formed by a long hole substantially in the X direction is formed in the front upper portion of the cam 260, and an interlocking contact member support portion 260c is formed in the rear lower portion of the cam 260. Yes. The connecting member 220b is connected to the contacting / separating member connecting portion 260b in a state of being fitted with play. Accordingly, when the surface of the contact / separation member connecting portion 260b and the connection member 220b come into contact with the rotation of the cam 260, it is pushed and approaches or separates in the vertical direction, that is, the photosensitive drum 12 (see FIG. 10). Move in the direction. An urging member other end support portion 260d is formed diagonally forward and downward of the interlocking contact member support portion 260c. A biasing spring 19 is mounted between the stage 221 (see FIG. 10) and the biasing member other end support portion 260d. The biasing spring 19 applies a force that always pulls the biasing member other end support portion 260d in the X direction. In other words, the cam 260 is urged by the urging spring 19 in the direction in which the contact / separation member connecting portion 260b rotates upward with the direction changing rotary shaft 18 as the center. In a normal state, the supported portion 270b that rotates and moves integrally with the cam 260 pushes the moving member (not shown) forward by the biasing force of the biasing spring 19, so that the connecting shaft 116 moves toward the shaft connecting recess 113c. It moves and the connection of the operation connecting member 113 and the moving member (not shown) is maintained.

  A vertically moving member 270 is supported on the interlocking contact member support portion 260 c of the cam 260. The vertically moving member 270 includes a trapezoidal contact member main body 270a, a supported portion 270b extending rearward from the rear surface of the contact member main body 270a, and an interlocking contact portion 270c integrally formed on the upper portion of the contact member main body 270a. Have. The supported portion 270b passes through the stage 221 (see FIG. 10) and is fixed to the interlocking contact member support portion 260c. Therefore, the vertical movement member 270 rotates integrally with the cam 260.

  When the lever 225 has the positional relationship shown in FIG. 11 in conjunction with the opening of the cover 91, the retract member 220 moves in the −X direction. At this time, the interlocking contact portion 270c of the up and down moving member 270 lifts the lever 58 (see FIG. 3) of the developing unit 15 in conjunction with the rotation of the cam 260 about the rotating shaft 18 for direction conversion.

(Developer contact / separation operation)
FIG. 13 is a diagram for explaining the separation operation of the developing device 15. FIG. 13A shows a state in which the developing device 15 is disposed at a position close to the developing device, and FIG. 13B shows a state in which the developing device 15 has been moved to a developing device separation position.
As shown in FIG. 13, the developing unit 15 performs the contact / separation operation with respect to the photosensitive drum 12 by the rotation operation with the position Q as the rotation center.

The developing device 15 is provided with a lever 58 that is fixed integrally with the support container 51 at a position facing the up-and-down moving member 270 of the retracting mechanism of the LPH 14. As shown in FIG. 13A, when the LPH 14 is set at the exposure apparatus proximity position (see FIG. 10), when the cam 260 pushes up the LPH 14 toward the photosensitive drum 12, The moving member 270 is located below the lever 58 and does not apply any force to the lever 58.
On the other hand, as shown in FIG. 13B, in the state where the LPH 14 is set at the exposure apparatus separation position (see also FIG. 11), when the cam 260 pushes the LPH 14 toward the photosensitive drum 12, The vertically moving member 270 is pushed up, and an upward force is applied to the lever 58. As a result, the lever 58 is lifted upward, and the developing device 15 rotates around the position Q and is separated from the photosensitive drum 12.

In order to set the LPH 14 again to the exposure apparatus proximity position, the lever 225 is tilted to the right side in FIG. 11 and set to return to the original position shown in FIG. Then, the retract member 220 slides from the back side to the front side (left side in FIG. 11). As a result, the inclination angle of the cam 260 becomes approximately 90 °, and accordingly the LPH 14 moves upward and is again set at the exposure apparatus proximity position. In this state, the LPH 14 is fixed in the Y-direction position by the first projecting members 251F and 251R and the Y-direction support members 122F and 122R. Further, the X-direction position and the Z-direction position of the LPH 14 are fixed by the second projecting members 252F and 252R and the XZ-direction support members 123F and 123R.
Then, as the cam 260 rises at an inclination angle of approximately 90 °, the vertical movement member 270 moves downward. As a result, the lever 58 moves downward, and the developing device 15 is set to the developing position again.
As described above, in this embodiment, the cam 260, the up and down moving member 270, the lever 58, and the like constitute an example of the developing device contacting / separating means. Further, the cam 260, the vertically moving member 270 integrally attached to the cam 260, the lever 58 attached to the developing device 15, the retracting member 220, and the like perform the contacting / separating operation of the exposure device contacting / separating means. It functions as an example of interlocking means for interlocking with the means.

In the image forming apparatus 1 of the present embodiment, the LED print head (LPH) 14 as an exposure apparatus is used, but the present invention is not limited to this. For example, an exposure apparatus that scans and exposes laser light may be used.
In the above embodiment, the configuration in which the four image forming units are covered with one cover has been described, but the present invention is not limited to this. For example, the present invention can be applied even to an image forming apparatus having only one image forming unit such as a monochrome copying machine. Further, two covers may be provided, and each of the two covers may cover two of the four image forming units. Further, for example, the image forming unit may be divided into a black image forming unit and another color image forming unit and covered with a cover.
In the above embodiment, the image forming apparatus of the type that employs the intermediate transfer belt as an example of the transfer belt has been described, but the present invention is not limited to this. For example, the present invention can be applied to an image forming apparatus that employs a medium conveying belt that conveys a recording medium such as recording paper as an example of a transfer belt and directly transfers toner to the recording medium.

1 is a diagram illustrating an example of an overall configuration of an image forming apparatus. It is a cross-sectional block diagram which shows the structure of the LED print head (LPH) shown in FIG. FIG. 2 is a cross-sectional configuration diagram illustrating a configuration of a developing device illustrated in FIG. 1. FIG. 6 is a diagram illustrating a state in which a cover is attached to four image forming units. It is a figure which shows the principal part which the transfer belt retract handle has fixed the cover. FIG. 10 is a diagram illustrating a state in which the transfer belt retract handle is operated and the cover is unlocked. FIG. 5 is a diagram for explaining a mechanism when an intermediate transfer belt is separated from a photosensitive drum by operating a transfer belt retract handle. It is a figure which shows a state when a cover is opened. It is a figure which shows a state when a transfer belt retract handle exists in the 2nd position shown in FIG. It is a figure which shows a state when LPH exists in exposure apparatus proximity position. It is a figure which shows a state when LPH exists in an exposure apparatus separation position. It is an enlarged view around a vertically moving member. It is a figure explaining the separation operation of a developing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus, 10 ... Image forming process part, 11 (11Y, 11M, 11C, 11K) ... Image forming unit, 12 ... Photosensitive drum (image holding body), 14 ... LED print head (LPH) (exposure device) 15 ... developer, 20 ... intermediate transfer belt (transfer belt), 58 ... lever, 71 ... transfer belt retract handle (first operation unit, lever), 73 ... flange (first operation unit), 80 ... Lock mechanism, 81 ... Lever lock, 82 ... Protrusion receiver, 83 ... Torsion spring, 91 ... Cover (second operation part, cover member), 93 ... Protrusion, 151 ... Slider, 152 ... Cam, 153 ... Cam receiver DESCRIPTION OF SYMBOLS 154 ... Energizing spring, 155 ... Movement direction conversion member, 220 ... Retract member, 225 ... Lever, 260 ... Cam, 270 ... Vertical movement member

Claims (4)

An image carrier that holds the image and is detachably disposed;
An exposure device that is disposed around the image carrier and exposes the image carrier to form a latent image;
A developing device for developing a latent image disposed around the image carrier and formed by the exposure device;
A transfer belt that is disposed in contact with the image carrier and transfers the image developed by the developing device , or transports a recording material to which the image is transferred and transfers the image to the recording material ;
A cover member that moves between a state that covers at least the image carrier and the exposure apparatus and a state that it does not cover;
A lever that moves between a position where the cover member is pressed and a position where the cover member is not pressed;
Transfer belt contacting / separating means for moving the transfer belt by operating the lever between a transfer belt contact position where the transfer belt contacts the image carrier and a transfer belt separation position separated from the image carrier. When,
An exposure apparatus that moves and moves the exposure apparatus by operating the cover member between an exposure apparatus proximity position in which the exposure apparatus is close to the image carrier and an exposure apparatus separation position that is separated from the image carrier. Means,
A lock mechanism for locking movement of the lever ;
With
The lever is positioned at a position to press the cover member when the transfer belt is at the transfer belt contact position, and is positioned to not press the cover member when the transfer belt is at the transfer belt separation position,
The cover member is disposed at a position that covers the image carrier when the exposure apparatus is in the proximity position of the exposure apparatus, and is disposed at a position that does not cover the image carrier when the exposure apparatus is at the separation position of the exposure apparatus. And the locking mechanism is operated to lock the lever . An image carrier that holds the image and is detachably disposed;
An exposure device that is disposed around the image carrier and exposes the image carrier to form a latent image;
A developing device for developing a latent image disposed around the image carrier and formed by the exposure device;
A transfer belt that is arranged in contact with the image carrier and transfers the image developed by the developing unit or conveys a recording material to which the image is transferred and transfers the image to the recording material;
A transfer belt that moves the transfer belt by an operation of the first operation unit between a transfer belt contact position where the transfer belt contacts the image carrier and a transfer belt separation position separated from the image carrier. Contact and separation means;
An exposure apparatus that moves the exposure apparatus by an operation of a second operation unit between an exposure apparatus proximity position where the exposure apparatus is close to the image carrier and an exposure apparatus separation position separated from the image carrier. Contact and separation means;
A locking mechanism that locks the first operating portion when the exposure apparatus is at the exposure apparatus separation position;
A developing device contacting / separating means for moving the developing device between a developing device proximity position where the developing device is close to the image holding member and a developing device separation position where the developing device is separated from the image holding member;
With
The first operation unit prohibits a user operation on the second operation unit when the transfer belt is in the transfer belt contact position,
The second operation unit is disposed at a position that inhibits a user's operation to attach or detach the image holding member when the exposure apparatus is in the proximity position of the exposure apparatus, and when the exposure apparatus is at the exposure apparatus separation position, Arranged at a position that allows the image carrier to be attached and detached,
The developing device contacting / separating means is interlocked with the exposure apparatus contacting / separating means, and the developing device contacting / separating means is operated when the second operation unit is operated so that the exposure apparatus is positioned near the exposure apparatus. the vessel is moved to the developing unit adjacent position, the exposure apparatus distant position when it comes to be operated such that the developing device moving means is the developing device separation images forming device you and moving into position. An image holding member, an exposure device that exposes the image holding member to form a latent image, and a developing unit that develops the latent image formed by the exposure device are arranged at regular intervals. A plurality of image forming units;
The image formed by the plurality of image forming units is arranged to face the plurality of image forming units , or a recording material to which the image is transferred is conveyed and the image is transferred to the recording material. A transfer belt;
A cover member that moves between a state in which at least the image carrier and the exposure apparatus of the image forming unit are covered and a state in which the image forming unit is not covered;
A lever that moves between a position where the cover member is pressed and a position where the cover member is not pressed;
The transfer belt is moved by operating the lever between a transfer belt contact position where the transfer belt contacts the image carrier of the plurality of image forming units and a transfer belt separation position separated from the image carrier. A transfer belt contacting / separating means to be operated;
The cover member between an exposure device proximity position where the exposure devices of the plurality of image forming units are close to the image carrier of the plurality of image formation units and an exposure device separation position which is separated from the image carrier. Exposure apparatus contacting / separating means for moving the exposure apparatus by the operation of
A lock mechanism for locking the movement of the lever ,
The lever is positioned to press the cover member when the transfer belt is at the transfer belt contact position, and is positioned to not press the cover member when the transfer belt is at the transfer belt separation position.
The cover member is disposed at a position that covers the image carrier when the exposure device of at least two of the plurality of image forming units is in the proximity of the exposure device, and the exposure device is An image forming apparatus, wherein the image forming apparatus is disposed at a position where the image holding member is not covered when the exposure apparatus is in the separated position, and the lever is locked by operating the lock mechanism . An image holding member, an exposure device that exposes the image holding member to form a latent image, and a developing unit that develops the latent image formed by the exposure device are arranged at regular intervals. A plurality of image forming units;
The image formed by the plurality of image forming units is arranged to face the plurality of image forming units, or a recording material to which the image is transferred is conveyed and the image is transferred to the recording material. A transfer belt;
The transfer operation is performed by operating the first operation unit between a transfer belt contact position where the transfer belt contacts the image carrier of the plurality of image forming units and a transfer belt separation position separated from the image carrier. A transfer belt contacting / separating means for moving the belt;
The exposure apparatus of the plurality of image forming units has a second position between an exposure apparatus proximity position that is close to the image holding body of the plurality of image forming units and an exposure apparatus separation position that is separated from the image holding body. Exposure apparatus contacting / separating means for moving the exposure apparatus by operating the operation unit;
A locking mechanism that locks the first operating portion when the exposure apparatus is at the exposure apparatus separation position;
Development in which the developing device of the image forming unit moves the developing device between a developing device proximity position near the image holding member of the image forming unit and a developing device separation position separated from the image holding member. Instrumentation and separation means;
The operation of the exposure device contacting / separating means with respect to the exposure device of at least two or more of the plurality of image forming units, and the developing device contacting / separating means with respect to the developing device of the two or more image forming units. An interlocking means for interlocking the operation,
With
The first operation unit prohibits a user operation on the second operation unit when the transfer belt is in the transfer belt contact position,
The second operation unit is configured to hold the image of the two or more image forming units by a user when the exposure devices of at least two or more of the plurality of image forming units are in the proximity of the exposure device. Arranged at a position that obstructs the body attaching / detaching operation, and arranged at a position that allows the image holding body to be attached / detached when the exposure apparatus is at the exposure apparatus separation position;
When the second operation unit is operated so that the exposure apparatuses of the two or more image forming units are in the proximity position of the exposure apparatus, the interlocking unit moves the developing device contact / separation unit to the exposure device contact / separation unit. The developing devices of the two or more image forming units are moved to the developing device proximity position in conjunction with the exposure device, and are moved to the developing device separation position when operated to be the exposure device separation position. the images forming device you.

Images