JP2001075458A - Image forming unit and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplish a storage space saving, compact image forming unit with a handle. SOLUTION: A rectangular recessed part 201 is formed in a longitudinal direction on the rotational outer peripheral surface of a developing unit 35, and the handle 200 formed of a rectangular elastic thin plate is stored in the recessed part 201. Oblong holes 202 extending in the longitudinal direction of the handle 200 are formed at both ends of the handle 200, and each oblong hole 202 is engaged with a locking member 203 planted on the recessed part 201. The handle 200 is made in an energized state so as to be stored in the recessed part 201 by its own elasticity (not gripped).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus applicable to a printer, a copying machine, a facsimile, and the like, and an image forming unit used for the same.

[0002]

2. Description of the Related Art Many conventional image forming apparatuses, in particular, image forming units used therein, are provided with a handle for easy carrying. For example, Japanese Patent Publication No. Hei 2-11155 discloses a handle 300 formed integrally with an image forming unit main body 301 as shown in FIG.

In this type of image forming apparatus,
It is necessary to detect the remaining amount of toner in the image forming unit. As a technique for detecting the remaining amount of toner, for example, a technique disclosed in Japanese Patent Laid-Open No. 6-317986 is known. That is, in this publication, when the developing cartridge is positioned at the developing position, the developing cartridge is positioned on a straight line connecting the rotary unit, which is the holding member of the switching mechanism, and the position outside the position sandwiching the developing cartridge. There is disclosed an image forming apparatus in which a light transmitting window is provided in a developing device and an opening is provided in a developing cartridge so as to have an optical path passing through a toner storage portion of the developing device. In this apparatus, the remaining amount of the toner in the toner storage unit is detected by a light transmission method between the rotary unit and the position outside the position sandwiching the developing cartridge for the developing cartridge positioned at the developing position. It has been like that.

[0004]

However, in the above-described configuration of the image forming unit having the conventional handle, the handle is formed integrally with the image forming unit main body.
It is necessary to secure a large space for accommodating the image forming unit in the image forming apparatus, and as a result, the size of the image forming apparatus cannot be reduced.

Further, in the above-described conventional image forming apparatus provided with the toner remaining amount detecting means, the toner in the toner storage section is interposed between the rotary unit and the position outside the position sandwiching the developing cartridge by a light transmission method. Since the remaining amount is detected, the optical path for detection becomes longer. As a result, the optical sensor for detecting the remaining amount of toner becomes special, and the accuracy may be reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and provides a compact image forming unit having a handle and requiring no storage space, and an image forming apparatus using the same. The purpose is to: Another object of the present invention is to provide an image forming unit capable of detecting the remaining amount of toner in a toner storage unit with a simple configuration without lowering detection accuracy, and an image forming apparatus using the same. I do.

[0007]

In order to achieve the above object, a first configuration of an image forming unit according to the present invention comprises an image forming unit main body having image forming means, a gripping posture capable of being gripped, and holding down. A handle that is provided on the image forming unit main body so as to be able to take a non-gripping posture, and is always urged to take the non-gripping posture by its own elastic force. According to the first configuration of the image forming unit, it is possible to realize a compact image forming unit having a handle, which does not take up a storage space as compared with the conventional image forming unit.

Further, the first of the image forming units of the present invention is provided.
In the above configuration, the handle is made of an elastic plate having long holes at both ends, and is attached to the mounting surface of the image forming unit main body via the long holes by a locking member, and is brought into contact with or close to the mounting surface. It is preferable to be able to take a non-holding posture to perform and a holding posture in which at least a part thereof is separated from the mounting surface. According to this preferred example, an image forming unit having a handle can be realized at a low cost with an extremely simple configuration.

Further, the first of the image forming units of the present invention.
In the configuration, the plurality of image forming units are rotatably arranged in a vertical plane, and the plurality of image forming units are sequentially moved to an image forming position to form an image by using an image forming unit used in an image forming apparatus. Preferably, the handle is provided on the rotating outer peripheral surface of the image forming unit main body. According to this preferred example, the image forming unit can be easily attached to and detached from the image forming apparatus. In this case, it is preferable that the handle is urged to take a non-gripping posture with a stronger elastic force than to take a gripping posture by its own weight. According to this preferred example, the handle of the image forming unit that has reached the lowermost position does not assume a gripping posture due to its own weight. In this case, it is preferable that a photoconductor and a developing device are provided, and the photoconductor is exposed on the rotation outer peripheral surface of the image forming unit main body. According to this preferred example,
It becomes easy to transfer the toner image on the photoreceptor onto the transfer material. In this case, it is preferable that the handle in the non-grip posture is inside the rotation locus plane of the photoconductor, and the handle in the grip posture is outside the rotation locus plane of the photoconductor. According to this preferred example, when rotating the image forming unit in the image forming apparatus, the handle does not come into contact with the transfer material without complicated movement.

Further, the first of the image forming units of the present invention is provided.
Is preferably composed of a photoreceptor unit for supporting the photoreceptor and a developing unit for supporting the developing device, and a handle is preferably provided on the developing unit side.
According to this preferred example, since the handle is provided on the side of the developing unit in which a heavy object such as a developing device is incorporated, it is possible to balance when the image forming unit is hung down with the handle. If the handle is provided on the developing unit side in this way, a sufficient space for disposing the handle can be secured.

Further, a first configuration of the image forming apparatus according to the present invention includes a unit rotating body that rotatably supports a plurality of image forming units in a vertical plane, and sequentially forms the plurality of image forming units. An image forming apparatus for forming an image by moving the image forming unit to a position, wherein the image forming unit can take an image forming unit main body having an image forming unit, a gripping posture that can be gripped, and a non-gripping posture that suppresses gripping. Handle provided on the image forming unit main body so as to always take the non-grip posture by its own elastic force, and the handle is provided on the rotating outer peripheral surface of the image forming unit main body. It is characterized by being provided.

Further, in the first configuration of the image forming apparatus of the present invention, an opening / closing door for attaching and detaching an image forming unit is provided above the unit rotating body, and the image forming apparatus mounted on the unit rotating body is provided. It is preferable that the handle in the holding posture of the unit can be pressed by the opening / closing door. According to this preferred example, even if the user forgets to set the handle in the non-grip position, after replacing the image forming unit, simply close the opening / closing door and move the handle to the non-grip position. Can be. In this case, it is preferable that the opening / closing door is provided with a projection that can contact the handle in the holding posture of the image forming unit.

A second configuration of the image forming apparatus according to the present invention includes a unit rotating body that supports a plurality of image forming units so as to be rotatable in a vertical plane, and sequentially forms the plurality of image forming units. An image forming apparatus for forming an image by moving the image forming unit to a position, wherein the image forming unit includes an image forming unit main body, a photoconductor exposed on a rotation outer peripheral surface of the image forming unit main body, and the image forming unit main body. Wherein the handle of the image forming unit in the unit rotating body at the replacement position of the image forming unit is disposed behind the photosensitive member when viewed from the front side of the image forming apparatus. And According to the second configuration of the image forming unit, when replacing the image forming unit,
It is possible to prevent the worker's finger from contacting the photoconductor exposed outside.

A third configuration of the image forming apparatus according to the present invention includes a unit rotating body that rotatably supports a plurality of image forming units in a vertical plane, and sequentially forms the plurality of image forming units. An image forming apparatus for forming an image by moving to a position, wherein the image forming unit comprises a photoconductor unit supporting a photoconductor, a developing unit supporting a developing device, and a handle, and The image forming unit in the unit rotator at a replacement position of the image forming unit is configured such that the image forming unit in the unit rotating body at the replacement position of the image forming unit is the photosensitive unit and the developing unit from the front side of the image forming apparatus. And a handle is provided on the developing unit side.
According to the third configuration of the image forming apparatus, the state in which the handle of the image forming unit in the unit rotating body at the replacement position of the image forming unit is disposed behind the photosensitive member when viewed from the front side of the image forming apparatus. can do. as a result,
When replacing the image forming unit, it is possible to prevent the finger of the operator from contacting the photoconductor exposed outside.

In the second or third configuration of the image forming apparatus of the present invention, it is preferable that the replacement of the image forming unit from the rear side of the image forming apparatus is restricted. According to this preferred example, it is possible to reliably prevent the operator's finger from coming into contact with the photoconductor when the image forming unit is replaced. In this case, it is preferable that an opening / closing door for attaching / detaching the image forming unit is provided above the unit rotating body, and replacement of the image forming unit from the rear side of the image forming apparatus is regulated by the opening / closing door. .

Further, the second part of the image forming unit according to the present invention is provided.
Is an image forming unit used in an image forming apparatus in which a plurality of image forming units are rotatably arranged in a vertical plane, and the plurality of image forming units are sequentially moved to an image forming position to form an image. Further, a light-transmitting detection window for detecting the remaining amount of toner is provided on the rotation outer peripheral surface of the image forming unit main body communicating with the toner hopper.
According to the second configuration of the image forming unit, since the light-transmitting detection window for detecting the remaining amount of toner is provided on the rotation outer peripheral surface of the image forming unit main body communicating with the toner hopper, the detection window is provided. By arranging a detecting member such as a light emitting element and a light receiving element in the vicinity of, the remaining amount of toner can be detected, so that the optical path for detection can be shortened. As a result, the accuracy of detecting the remaining amount of toner can be improved. Further, since the translucent detection window is exposed outside the image forming unit main body, it is possible to take out the image forming unit from the image forming apparatus main body and visually check the remaining amount of toner.

Further, in the second configuration of the image forming unit of the present invention, it is preferable that the detection window is located at a corner of the rotation outer peripheral surface of the image forming unit main body. According to this preferred example, since the detection window is located at the bottom of the toner hopper, it is easy to detect even a small amount of toner.

Further, in the second configuration of the image forming unit of the present invention, a detection window having a pair of side surfaces facing each other is provided in a recess formed in the toner hopper, and the toner window is provided near the pair of side surfaces. It is preferable that a reflection surface for bending the light for detecting the remaining amount be provided. According to this preferred example, it is not necessary to dispose a detecting member such as a light-emitting element and a light-receiving element in a recess provided in the toner hopper, and the detection optical path can be relatively short.

In the second configuration of the image forming unit of the present invention, it is preferable that a cleaning member for cleaning the detection window is provided. According to this preferred example, the detection window can be appropriately cleaned to increase the accuracy of detecting the remaining amount of toner.

A fourth configuration of the image forming apparatus according to the present invention includes a unit rotating body that supports a plurality of image forming units so as to be rotatable in a vertical plane, and sequentially forms the plurality of image forming units. An image forming apparatus for forming an image by moving to a position, wherein a light-transmitting detection window for detecting a remaining amount of toner is provided on a rotation outer peripheral surface of an image forming unit main body communicating with a toner hopper. Features.

Further, in the fourth configuration of the image forming apparatus according to the present invention, it is preferable that the detection window is located at a corner of the rotation outer peripheral surface of the image forming unit main body.

Further, in the fourth configuration of the image forming apparatus of the present invention, a detection window having a pair of side surfaces facing each other is provided in a recess formed in the toner hopper, and a toner window is provided near the pair of side surfaces. It is preferable to provide a reflecting surface for bending the light for detecting the remaining amount of light. Also,
In this case, it is preferable that a detection unit that emits and receives light for detecting the remaining amount of toner is provided to face the rotating outer peripheral surface of the image forming unit main body.

In the fourth configuration of the image forming apparatus of the present invention, it is preferable that the remaining amount of toner is detected at a position different from the image forming position. According to this preferred example, it is possible to easily arrange the detecting means for emitting and receiving the light for detecting the remaining amount of the toner. In this case, it is preferable that the detection of the remaining amount of toner is performed when the detection window is located below a horizontal line including the rotation center of the unit rotator. According to this preferred example, it is possible to detect even a small amount of toner. In this case, it is preferable that the remaining amount of toner is detected when the image forming unit is located at a position facing the image forming position. In this case, it is preferable that a cleaning member for cleaning the detection window is provided, and the detection window is cleaned only at the image forming position. According to this preferred example, since it is not necessary to provide a mechanism for driving the cleaning member at a plurality of locations, the configuration of the image forming apparatus can be simplified.

In the fourth configuration of the image forming apparatus of the present invention, the remaining amount of the toner of the image forming unit of the same color is detected a plurality of times while the unit rotating body rotates a plurality of times, and the result is obtained. It is preferable to determine the remaining amount of toner based on the following formula. According to this preferred example, it is possible to reduce the detection error and accurately detect the remaining amount of toner.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to embodiments.

FIG. 1 is a sectional view showing an image forming apparatus according to one embodiment of the present invention, FIG. 2 is an external perspective view showing an image forming unit according to one embodiment of the present invention, and FIG. A sectional view, FIG. 4 is a BB sectional view of FIG. 2, and FIG.
6 is a left side view without the gear cover of FIG. 2, and FIG. 7 is an external perspective view showing a state in which the handle of the image forming unit in one embodiment of the present invention is in a gripping posture. FIG.

In FIG. 1, the right end face is the front face of the apparatus, and a carriage 2 is provided at substantially the center of the apparatus main body 1, a front alligator 1A is provided at the front face, and a top door 17 is provided at the top face.

1 to 3, reference numeral 30 denotes a photosensitive member; 34, a corona charger for uniformly and negatively charging the photosensitive member 30;
Denotes a developing roller 31, a supply roller 217 for supplying toner,
The developing unit includes a doctor blade 24 for forming a toner layer and a toner hopper 39 that stores the toner 32.
Reference numeral 36 denotes a rubber cleaning blade for cleaning the toner remaining on the surface of the photoreceptor 30 after transfer, and reference numeral 38 denotes a waste toner case for storing waste toner scraped off by the cleaning blade 36. Vessel 3
4 and the photoconductor 30 are attached to the photoconductor unit 37.
Is configured. Further, the photoconductor unit 37 and the developing unit 35 are swingably connected by a fulcrum pin 90 to be integrated, and thereby the image forming unit 3 is configured. The photoconductor 30, the developing roller 31, and the supply roller 217 are rotatably supported, and rotate in the directions indicated by arrows. The toner 32 is a negatively charged toner in which a pigment is dispersed in a polyester resin.
5, the toner is supplied from the supply roller 217 to the developing roller 31, and is thinned by the doctor blade 24. Then, the toner is supplied to the photoconductor 30, and the electrostatic latent image on the photoconductor 30 is developed.

The carriage 2 has four color (yellow, magenta, cyan, and black) image forming units 3Y and 3Y.
M, 3C and 3Bk are accommodated. The carriage 2 is rotatably supported by the circular tube 21, whereby the photoconductors 30 of the image forming units 3 of the respective colors are sequentially moved between the image forming position 10 and other retreat positions, and the image forming units 3 are moved. Can be switched.

The image forming operation position of the image forming unit 3 in the carriage 2 is only at the image forming position 10 where the photoreceptor 30 is irradiated with the pixel laser signal light 8 and the transfer belt unit 5 and the photoreceptor 30 are in contact with each other. is there. The image forming unit 3
The image forming position 10 is connected to a drive source and a power supply of the apparatus main body 1, thereby performing an image forming operation. The other positions are the retracted positions, and no image forming units 3 operate in this position.

As shown in FIGS. 2 to 4, the image forming unit 3 is provided with a handle 200 on its rotating outer peripheral surface (a surface along the outer peripheral surface of the carriage 2 in FIG. 1). , The image forming unit 3 can be carried around by hand. Handle 20
Numeral 0 is provided on the side of the developing unit 35 in which a heavy object such as the developing roller 31 is incorporated.
The balance can be obtained when the image forming unit 3 is hung down by holding the hand 0. Further, if the handle 200 is provided on the developing unit 35 side, a sufficient space for disposing the handle 200 can be secured. Further, since the handle 200 is provided on the outer peripheral surface of the rotation of the image forming unit 3 as described above, the attachment and detachment of the image forming unit 3 to and from the carriage 2 of the apparatus main body 1 become easy.

A rectangular concave portion 201 is formed along the longitudinal direction of the rotating outer peripheral surface of the developing unit 35, and a handle 200 made of an elastic rectangular thin plate is stored in the concave portion 201. Have been able to put it. Since the handle 200 is housed in the recess 201 as described above, the image forming unit 3 can be made more compact than the conventional one. At both ends of the handle 200, a long hole 202 extending in the longitudinal direction of the handle 200 is provided.
Is engaged with a locking member 216 provided upright. And
The handle 200 is brought into contact with the bottom surface of the
1, the locking member 216 is inserted into the long hole 202.
Is in contact with the inner end of the. The handle 200
Is biased so as to take a state of being housed in the concave portion 201 (non-holding posture) by its own elastic force. In this non-holding posture, the handle 200 is located inside the rotation locus plane of the photoconductor 30. Thereby, when rotating the image forming unit 3 in the image forming apparatus, the handle 200 can be moved without complicated movement.
Does not contact the transfer belt unit 5. Note that the image forming unit 3 rotates in a vertical plane while being housed in the carriage 2 (FIG. 1). In this case, the handle 200 of the image forming unit 3 that has come to the lowermost position has a gripping posture due to its own weight. It is desirable that the elastic force of the handle 200 is set to be larger than the force by which the handle 200 takes a gripping posture due to its own weight.

Further, an introduction groove 20 is provided at the center of the developing unit 35 in the longitudinal direction.
3 are formed. The introduction groove 203 extends below the handle 200 with a step difference from the recess 201, whereby a sufficient space for inserting a finger is secured below the handle 200 stored in the recess 201.

Since the handle 200 is constructed as described above, if the user inserts his / her finger through the introduction groove 203 and grips the handle 200, the weight of the image forming unit 3 causes the handle 2
00, the outer ends of the long holes 202 are in contact with the locking member 216, and the handle 200 is protruded from the recess 201 (gripping posture) (the state shown by the two-dot chain line in FIG. 4, the state shown in FIG. 7). . In this state of the gripping posture, the handle 200 is located outside the rotation locus plane of the photoconductor 30.

As the material of the handle 200, it is desirable to use ABS, polycarbonate, or the like. Here, the specific length of the handle 200 is 170 m.
m, the width is 18 mm, and the thickness is 1.2 mm.

The image forming unit 3 is detachably mounted on the apparatus main body 1. When the image forming unit 3 needs to be replaced, the carriage 2 is rotated to mount the image forming unit 3 of the color to be replaced. It can be located below the face door 17 and can be replaced by opening the top door 17. Image forming unit 3
Is exchanged by gripping the handle 200 provided on the rotating outer peripheral surface of the developing unit 35, so that the image forming unit 3 can be easily attached to and detached from the apparatus main body 1. The image forming unit 3 is usually replaced from the front side of the apparatus (the right side of the image forming apparatus shown in FIG. 1) (see FIGS. 1 and 8).
Here, the image forming unit 3 in the carriage 2 at the exchange position is arranged in the order of the photoconductor unit 37 and the developing unit 35 from the front side of the apparatus, and the handle 200 is provided on the developing unit 35 side. That is, at the replacement position of the image forming unit 3, the handle 200 is disposed deeper than the photoconductor 30 when viewed from the front side of the apparatus. As described above, since the handle 200 is arranged behind the photoreceptor 30 when viewed from the front side of the apparatus (the position where the worker stands), when the image forming unit 3 is replaced, the handle of the worker is replaced. The finger can be prevented from contacting the photoconductor 30 exposed to the outside. When the image forming unit 3 is replaced, the top door 17 is opened so as to prevent the replacement of the image forming unit 3 from the rear side of the apparatus, and the replacement of the image forming unit 3 from the rear side of the apparatus is restricted. Is done.
Thereby, it is possible to reliably prevent the operator's finger from contacting the photoconductor 30 when the image forming unit 3 is replaced.

A projection 204 is provided on the inner surface of the top door 17, and the projection 204 when the top door 17 is closed is provided.
Is formed along the outer peripheral surface of the carriage 2. The handle 200 is stored in the concave portion 201 by the elastic force of the handle 200 only by lightly pressing with a fingertip, and is in a non-gripping position.
If the handle 4 is provided, even if the handle 200 is forgotten to be in the non-gripping position, the projection 204 can be obtained simply by closing the top door 17 after replacing the image forming unit 3.
Can be brought into the non-gripping posture by contacting the handle 200 in the gripping posture (the state of the two-dot chain line in FIG. 4, the state of FIG. 7).

As shown in FIGS. 2, 5, and 6, a toner detecting case 205 having an arc-shaped cross section is provided at the longitudinal end of the developing unit 35 at the corner of the outer circumferential surface of the developing unit 35. Is provided. This toner detection case 205
Are formed in a recess 213 provided in the toner hopper 39 so as to be continuous with the toner hopper 39. The toner detection case 205 is made of a light-transmitting member.
Reflective surface 20 at an angle of 45 ° with the side surface of
6 are provided. Then, as shown in FIG. 5, the toner detecting case 205 on the outer peripheral surface of the rotation of the developing unit 35
The light emitted from the light emitting element 207 disposed opposite to the light source is reflected by one reflection surface 206 and enters the inside of the toner detection case 205 from one side surface (detection window) of the toner detection case 205, and the toner detection case Light emitted from the other side surface (detection window) of 205 and reflected by the other reflection surface 206 is received by a light receiving element 208 which is also arranged to face the toner detection case 205 on the outer peripheral surface of the developing unit 35. In the process, the remaining amount of toner in the toner hopper 39 is detected. That is, since the amount of light received by the light receiving element 208 differs depending on the remaining amount of toner in the toner hopper 39 (the amount of toner in the toner detection case 205), the amount of toner in the toner hopper 39 can be detected.
Since the remaining amount of the toner in the toner hopper 39 is detected by the above configuration, it is not necessary to dispose the detecting members such as the light emitting element 207 and the light receiving element 208 in the recess 213 provided in the toner hopper 39. Depress the detection member 21
It is not necessary to take in and out from 3 and the optical path for detection can be relatively short. Further, since the toner detection case 205 is formed of a light transmitting member, the image forming unit 3 can be taken out of the apparatus main body 1 and the remaining amount of toner in the toner hopper 39 can be visually checked.

As a member constituting the toner detection case 205, it is desirable to use an acrylic resin, a polystyrene resin, or the like.

The light emitting element 207 and the light receiving element 208
The image forming unit 3 located at a position facing the image forming position 10 shown in FIG.
C) is disposed near the carriage 2 so that the remaining amount of toner in the toner hopper 39 can be detected. That is, the toner remaining amount detection position is determined by the carriage 2
Are located below the horizontal line including the rotation center of the. At this detection position, the toner detection case 205 is located at the bottom of the toner hopper 39, so that even a small amount of toner can be detected. As shown in FIG. 1, at the image forming position 10, the toner in the toner hopper 39 is collected on the inner peripheral portion of the carriage 2. Light emitting element 207 and light receiving element 2 for detecting remaining amount
08 and the like must be provided on the inner peripheral portion of the carriage 2. For this reason, the light emitting element 20 for detecting the remaining amount of toner is used.
7. It is difficult to arrange the light receiving element 208 and the like,
As described above, the remaining amount of toner is detected at a position and orientation different from the image forming position 10, so that the light emitting element 207 and the light receiving element 208 for detecting the remaining amount of toner can be easily arranged. it can.

As shown in FIGS. 5 and 6, inside the toner detecting case 205, a cleaning member 209 for cleaning the inner wall surface of the toner detecting case 205 is provided.
Is provided. The cleaning member 209 includes a cleaning member main body 211 rotatably supported by the center shaft 210 and wing portions 212 provided on both ends of the cleaning member main body 211 so as to protrude to both sides. Then, both ends of the cleaning member body 211 clean the arc surface of the toner detection case 205, and the wings 212 clean both side walls (detection windows) of the toner detection case 205.
As described above, since the cleaning member 209 for cleaning the inner wall surface of the toner detection case 205 is provided inside the toner detection case 205, the inner wall surface of the toner detection case 205 is appropriately cleaned to detect the remaining amount of toner. Can be raised. The driving method of the cleaning member 209 will be described later.

In FIGS. 2 and 7, reference numeral 221 denotes a gear cover.

The transfer belt unit 5 has an image forming position 10
Is for copying the toner image formed on the photoconductor 30 of the image forming unit 3 and retransferring the copied toner image to recording paper. Transfer belt unit 5
Is a group of pulleys (a driving pulley 55A, a backup pulley 55B, a guide pulley 55C, and a tension pulley 55D) for suspending the intermediate transfer belt 50, the cleaner 51, and waste toner containing waste toner after cleaning. It is composed of a case 57, which are integrated and detachably attached to the apparatus main body 1.

The intermediate transfer belt 50 has a thickness of about 100 μm.
The endless belt-shaped semiconductive (medium resistance) urethane is coated with a fluororesin such as PFA or PTFE, and has a total thickness of 100 to 300 μm. In order to perform A4 size or letter size full color printing, the circumferential length of the intermediate transfer belt 50 is the length in the longitudinal direction of A4 image receiving paper which is the maximum image receiving paper size (2
97 mm).

The cleaner 51 is for cleaning and removing the toner remaining on the intermediate transfer belt 50, and includes a rubber cleaning blade 53 and a screw 52 for conveying the scraped toner to a waste toner case 57. It is configured. The cleaner 51 is provided to prevent the toner image on the intermediate transfer belt 50 from being scraped off while forming a color image on the intermediate transfer belt 50.
It is configured to rotate about the fulcrum 58 and to separate from the intermediate transfer belt 50.

The pulley 55 A of the pulley group for suspending the intermediate transfer belt 50 is a drive pulley for driving the intermediate transfer belt 50, and also serves as a backup for the cleaning blade 53. The pulley 55B is a backup pulley for the secondary transfer roller 9 that transfers the toner image on the intermediate transfer belt 50 to recording paper. Pulley 55
C is a guide pulley, which also serves as a roller for applying a primary transfer bias for transferring a toner image from the photoconductor 30 onto the intermediate transfer belt 50. The pulley 55D is a tension pulley that applies tension to the intermediate transfer belt 50. The intermediate transfer belt 50 is connected to these pulleys 5
5A, 55B, 55C, and 55D, and can be rotationally driven by rotation of the drive pulley 55A. Reference numeral 56 denotes a cover for protecting the intermediate transfer belt 50.

The transfer belt unit 5 is securely positioned at a predetermined position when the transfer belt unit 5 is mounted on the apparatus main body 1, and the portion facing the image forming position 10 is the photosensitive member 3 of the image forming unit 3.
Touch 0. At the same time, the transfer belt unit 5
Are electrically connected to the main body, and the driving pulley 55A is connected to the driving means on the main body, so that the intermediate transfer belt 50 is in a rotatable state.

The static elimination needle 7 is for preventing the toner image from being disturbed when the recording paper is separated from the intermediate transfer belt 50.

Reference numeral 6 denotes a laser exposure device disposed below the transfer belt unit 5.
Is a semiconductor laser (not shown), a polygon mirror 6
A, a lens system 6B, a first mirror 6C, and the like. The pixel laser signal light 8 corresponding to the time-series electric pixel signal of the image information is transmitted to the yellow image forming unit 3 shown in FIG.
Y photoconductor unit 37 and black image forming unit 3
It passes through the optical path 22 formed between the Bk and the developing unit 35. The pixel laser signal light 8 passes through the exposure window 97 of the circular tube 21, and is fixed to the apparatus main body 1 in the circular tube 21.
The light enters a mirror 98 (which is stationary irrespective of the circular tube 21), is reflected and passes through a gap 33 provided between the photoreceptor unit 37 of the image forming unit 3Y and the developing unit 35 to form an image forming position. The light enters the exposed portion on the left side of the photoconductor 30 located at 10 and scans and exposes the photoconductor 30 in the generatrix direction.

12 is a paper feed unit, 14 is a paper feed roller,
16 is a registration roller, 18 is a discharge roller, 13a, 1
Reference numerals 3b, 13c, and 13d denote paper guides that connect between these rollers, the contact point between the intermediate transfer belt 50 and the secondary transfer roller 9, and the fixing device 15.

The front alligator 1A is hinged to the apparatus main body 1 by a hinge shaft 1B, and can be opened by falling to the front. The fixing device 15, 2,
Next transfer roller 9, static elimination needle 7, paper guides 13a, 13b,
The front sides of 13c and 13d and the front side of the registration roller 16 are attached. When the front alligator 1A is moved forward, these components also fall down at the same time. For this reason, the front surface of the apparatus main body 1 can be largely released, and the transfer belt unit 5 can be detached from this portion, and the recording paper can be easily removed even in the case of a paper jam.

Next, the details of the positioning of the photosensitive member 30 and the drive mechanism at the image forming position 10 for accurately performing color matching of each color will be described with reference to FIGS.

FIG. 9 is an exploded perspective view showing a carriage and photosensitive member positioning mechanism and a driving mechanism of the image forming apparatus according to one embodiment of the present invention. FIG. 10 is an exploded perspective view of the image forming apparatus according to one embodiment of the present invention. FIG. 3 is a cross-sectional view of the carriage cut along a plane passing an image forming position.

As shown in FIGS. 9 and 10, tapered holes 4 for positioning the image forming unit 3 are provided at both ends of the photosensitive member 30.
Flanges 41R and 41L having 8R and 48L are adhesively fixed, and the outer periphery of the flanges 41R and 41L is fixed to the side wall of the photoconductor unit 37.
R and 43L are attached rotatably. A coupling claw 47 for rotating and driving the photoconductor 30 is provided at the tip of the flange 41R, and the coupling claw 47 can be engaged with a coupling plate 61 on the main body side.

A right side wall 20R and a left side wall 20L are fixed to the center circular tube 21 of the carriage 2. On each of the side walls 20R and 20L, partition ribs 23 are fixedly arranged at four positions so as to divide the inside of the carriage 2 into four parts. Each color image is provided in each space in the carriage 2 partitioned by the partition ribs 23. The forming unit 3 is arranged. Further, the circular tube 21 is provided with exposure windows 97 at a total of four positions through which the pixel laser signal light 8 for photoconductor exposure passes. Note that the carriage 2 is provided on the left and right main body side walls 1
R and 1L are rotatably supported via bearings 46R and 46L.

The carriage gear 2 is provided outside the left side wall 20L.
The carriage gear 28 is integrally formed, and the carriage gear 28 is connected to a carriage drive mechanism 86 provided on the main body side. The carriage drive mechanism 86 includes a worm 89 connected to a drive source (not shown), a worm wheel 88, and the worm wheel 88.
The carriage 2 is freely rotated and positioned by the rotational drive of the carriage drive mechanism 86.

45R and 45L are left and right main body side walls 1R and 1R.
L is a drop prevention guide for preventing the image forming unit 3 provided in the lower half along the outer periphery of the carriage 2 from dropping from the carriage 2.

The second mirror 98 is fixed to the main body side walls 1R, 1R near the center of the circular tube 21 by a fixing member (not shown).
L, and is configured to always remain stationary irrespective of the rotation of the carriage 2.

The side walls 20R, 20L are provided with notches 26R, 26L at the portions where the flanges 41R, 41L of the image forming unit 3 are inserted. This notch 26
The R, 26L and the partition rib 23 serve as a guide when the image forming unit 3 is mounted in the carriage 2. The image forming unit 3 is guided by the fall prevention guides 45R and 45L from the side or below the carriage 2 and does not detach from the carriage 2.

The dimensions of the notches 26R, 26L are set larger than the outer diameters of the flanges 41R, 41L.
When the photoconductor 30 is positioned at the image forming position 10 and is at the reference position, the photoconductor 30 is provided with play in all directions with respect to the carriage 2 at the regular position.
In the present embodiment, this play is ensured at about 1 mm, so that the positioning operation of the photoconductor 30 is not hindered even if the positioning accuracy of the carriage 2 is somewhat poor.

In order to accurately position the photosensitive member 30 at the image forming position 10 on both side walls 1 R and 1 L of the apparatus main body 1,
A photoreceptor driving mechanism 60 and a detent mechanism 80 are provided.

The photoconductor driving mechanism 60 is provided on the right main body side wall 1R, and includes an output shaft 70, a coupling plate 61 fixed to the output shaft 70 and rotating integrally with the output shaft 70, and an output shaft driving gear 71. And a drive mechanism for driving these. The output shaft 70 is movably and rotatably supported in a thrust direction by bearings 77 fixed respectively between the right main body side wall 1R and the substrate 67 fixed thereto.

At one end of the output shaft 70, a tip taper portion 75 having a convex tapered surface following the tapered hole 48R of the photosensitive member 30 is formed, and the other end of the output shaft 70 is small in the thrust bearing 69R. It is formed in a spherical shape so that it contacts in area. The output shaft driving gear 71 is a helical gear, and the output shaft driving gear 71 is fixed to the output shaft 70 in a state where the output shaft driving gear 71 meshes with the driving gear 72. Numeral 74 denotes a compression spring inserted between the bearing 77 and the output shaft drive gear 71. The compression spring 74 separates the output shaft 70 and the coupling plate 61 from the flange 41R on the photoconductor 30 side (see FIG. 10 indicates an engaged position).

The output shaft 70 is moved by a driving means (not shown) for moving the thrust bearing 69R to a position separated from the flange 41R and to an engagement position at which the tapered hole 48R and the tip tapered portion 75 shown in FIG. The driving-side gear 72 has a wide tooth width so that the output shaft driving gear 71 is engaged with the driving-side gear 72 at any position. ing. Output shaft 7
When 0 moves in the thrust direction, the output shaft driving gear 71
And the driving gear 72 move while sliding on each other's tooth surfaces.

The coupling plate 61 is for transmitting power by engaging with the coupling claw portion 47 of the flange 41R, and has eight coupling claws 65 at the tip.

Next, the detent mechanism 80 provided on the left main body side wall 1L will be described.

The detent mechanism 80 is supported between the left main body side wall 1L and the substrate 68 via a bearing 78, and is movable in the thrust direction by a driving mechanism (not shown) for moving the thrust bearing 69L and a compression spring 85. It is constituted by a rotatable detent shaft 81. At one end of the detent shaft 81, a taper hole 48L of a flange 41L is provided.
A tapered surface 84 is formed following the detent shaft 8.
The other end of 1 is formed in a spherical shape like the output shaft 70, and is pressed against the thrust bearing 69L. 85 is a spring stopper 82 fixed to the left side wall 1L and the detent shaft 81.
The compression spring 85 is inserted between
Is for always keeping the detent shaft 81 away from the flange 41L.

With the above arrangement, when the image forming unit 3 supported by the carriage 2 is carried to the image forming position and stopped when the output shaft 70 and the detent shaft 81 are separated from the flanges 41R and 41L of the photosensitive member 30, The thrust bearings 69 </ b> R and 69 </ b> L are pushed inward by the drive mechanism, and the tapered end 75 of the output shaft 70 is
The tapered surface 8 of the detent shaft 81 is inserted into the tapered hole 48R of R.
4 are respectively engaged with the tapered holes 48L of the flange 41L, and the photoconductor 30 is accurately positioned at the image forming position 10. When the output shaft driving gear 71 rotates with the output shaft 70 and the detent shaft 81 pressed inward, the coupling claw 65 of the coupling plate 61 is engaged with the coupling claw 47 of the flange 41R. The rotation of the output shaft 70 is transmitted to the photoconductor 30, and the photoconductor 30 is moved to the image forming position 10.
Rotate with. At this time, the output shaft 70 and the detent shaft 81
Since the photoconductor 30, the second mirror 98, and the laser exposure device 6 supported by the camera 2 are all positioned on the apparatus main body 1, the photoconductor 30 can be accurately positioned regardless of the position of the carriage 2. As a result, even if the color is switched, this relationship does not shift, so that no color shift occurs.

Next, the structure of the image forming unit 3 and the driving mechanism of the developing roller 31 in the present embodiment will be described in detail with reference to FIGS. 6 and 10 to 12.

FIG. 11 is a sectional view showing a swing lever portion provided in the developing unit according to one embodiment of the present invention, and FIG. 12 is a right side view of FIG.

First, a method of connecting the photosensitive unit 37 and the developing unit 35 in the image forming unit 3 will be described.

As shown in FIGS. 6, 10 and 12, a projection 91 is provided on the right side wall 37R of the photoreceptor unit 37, and a fulcrum pin 90 is press-fitted and fixed to the projection 91. A guide pin 108 is press-fitted and fixed to the left side wall 37L of the photoconductor unit 37. Further, a guide groove 115 for guiding the developing roller 31 in the direction of the photoconductor 30 is formed on the left side wall 37L of the photoconductor unit 37. The developing unit 35 is disposed inside the both side walls 37R and 37L of the photoconductor unit 37, and the right side wall 37R side of the photoconductor unit 37 is provided with a positioning hole 11 in a fulcrum pin 90.
6 is inserted and supported rotatably.

As shown in FIGS. 6 and 10 to 12, the developing roller 31 is rotatably supported by bearings 105 and 106 fixed to the right and left side walls 35R and 35L of the developing unit 35, respectively. The bearing 106 is fitted into the guide groove 115 on the left side wall 37L side of the photoconductor unit 37, and the left side of the developing unit 35 is
7 can move along the guide groove 115 together with the developing unit 35. The left side wall 3 of the developing unit 35
The guide pin 108 is inserted into the hole 107 provided in 5L. However, the positioning of the guide pin 108 is not performed by the guide pin 108, and both are arranged with a play of about 1 mm.

The photosensitive unit 37 and the developing unit 35 are combined in the above-described configuration, and the photosensitive unit 37 is
And the right side wall 35R of the developing unit 35
The fulcrum pin 9 is provided by a compression spring 102 applied between the two.
The developing roller 31 is stopped while being pressed against the photoreceptor 30. Also, a left side wall 37L of the photosensitive unit 37 and a left side wall 35L of the developing unit 35
Are the bearing 106 of the developing roller 31 and the photosensitive unit 3
The developing roller 31 is pulled toward the photoconductor 30 by a tension coil spring 110 that is stretched between the pin 111 and the pin 111 that is set on the left side wall 37 </ b> L of the printer 7, whereby the developing roller 31 is pressed against the photoconductor 30. Stop.

Next, the driving mechanism of the developing roller 31 will be described.

As shown in FIGS. 6, 10 and 11, the developing roller 31 includes a developing drive main body gear 62, a swing gear 94 attached to the main body side wall 1, and a developing roller gear 96 fixed to the developing roller 31. Is driven to rotate. The developing drive main body gear 62 includes a developing drive shaft 63 rotatably attached to the right main body side wall 1R and the substrate 67 via a bearing 66.
The developing drive shaft 63 is fixed to the developing drive shaft 6.
3 is rotated from the main body side via a developing drive pulley 64 fixed to the main body 3. The gear 99 is a gear fixed to the supply roller 217, and the gear 99 is a developing roller gear 96.
And an idler gear 214.

As shown in FIGS. 6 and 11, the swing gear 94
Is rotatably mounted via a pin 93 to a bearing 105 fixed to the right side wall 35R of the developing unit 35 and a swing lever 92 which is swingably mounted on the developing roller shaft 215 about the developing roller shaft 215. ing. A tension spring 104 is hung on the swing lever 92, thereby biasing the swing gear 94 toward the developing drive main body gear 62. The bottom surface of the swing lever 92 is supported by the fulcrum of the right side wall 37 </ b> R of the photosensitive unit 37. It stops by contacting the circular projection 91 around the pin 90.

When the carriage 2 on which the image forming unit 3 is mounted is driven to rotate, when the tips of the teeth of the developing drive main body gear 62 and the oscillating gear 94 come into contact with each other, the oscillating lever 92 resists the force of the tension spring 104. And the swing gear 94 escapes from the developing drive main body gear 62. When the image forming unit 3 reaches the image forming position 10, the swing gear 94 bites into the developing drive main body gear 62, but the swing lever 92 comes into contact with the circular projection 91 and is stopped. The distance between the center of the developing drive main body gear 62 and the center of the developing drive main body gear 62 are properly secured, and the developing roller 31 rotates in a state of being in contact with the photoconductor 30.

As shown in FIG. 6, the cleaning member main body 211 of the cleaning member 209 for cleaning the inner wall surface of the toner detecting case 205 described above.
Is driven to rotate via a developing drive main body gear 62, a swing gear 94, a developing roller gear 96, and an idler gear 214. That is, when the photosensitive member 30 of the image forming unit 3 is positioned at the image forming position 10 and the swing gear 94 meshes with the developing drive main body gear 62, the cleaning member main body 2
11 is driven to rotate. Therefore, the toner detection case 2
Cleaning at 05 is performed only at the image forming position 10, and cleaning of the toner detecting case 205 is not performed at the toner remaining amount detecting position. In this manner, the cleaning member main body 211 does not rotate at the toner remaining amount detection position, and the detection light is not blocked by the cleaning member main body 211, so that the remaining amount of toner can be accurately detected. If the cleaning of the toner detection case 205 is performed only at the image forming position 10, a mechanism for rotating and driving the cleaning member main body 211 is provided at the image forming position 10.
Since there is no need to provide a special device other than the above, the configuration of the device can be simplified. Note that the image forming unit 3 does not include a member for stirring the toner in the toner hopper 39, so that the remaining amount of toner may not be accurately detected. If the remaining amount of toner of the image forming unit 3 of the same color is detected a plurality of times during this process, and the remaining amount of toner is determined based on the result, the detection error is reduced, and the remaining amount of toner is reduced. Can be accurately detected.

Next, a case where an image is formed using the image forming apparatus configured as described above will be described.

When the power of the apparatus main body 1 is turned on in a state where the transfer belt unit 5 and the image forming units 3 of the respective colors are mounted at predetermined positions, the temperature of the fixing unit 15 rises and the polygon mirror 6A of the laser exposure apparatus 6 Starts spinning,
Preparation is completed. In some cases, immediately after the power is turned on, the initialization mode for maintaining the state of the photoconductor 30 and the intermediate transfer belt 50 may be operated.

When the preparation is completed, first, image formation by the yellow image forming unit 3Y at the image forming position 10 is started. Then, at the same time as the yellow photoconductor 30 connected to the drive source of the apparatus main body 1 starts rotating at the image forming position 10, the developing roller 31, the corona charger 34, and the intermediate transfer belt 50 start to move. The drive pulley 55A is driven from the apparatus main body 1 side, and the frictional force causes the intermediate transfer belt 50 to rotate in the direction of the arrow. Here, the photoconductor 3
The peripheral speed of 0 and the peripheral speed of the intermediate transfer belt 50 are set to be substantially equal. At this time, the secondary transfer roller 9 and the cleaner 51 are separated from the intermediate transfer belt 50.

The corona charger 34 on the surface of the photosensitive member 30
The detection means (not shown) detects the leading position of the intermediate transfer belt 50 in synchronization with the timing at which the uniformly charged portion comes to the exposure position, and synchronizes the image from the laser exposure device 6 with the detection signal. The photoconductor 30 is irradiated with the pixel laser signal light 8 corresponding to the signal. When the pixel laser signal light 8 is irradiated onto the uniformly charged photoconductor 30, an electrostatic latent image corresponding to the image signal is formed, and the electrostatic latent image is sequentially visualized by the developing unit 35. A toner image is formed. Next, the toner image formed on the photoreceptor 30 moves to a primary transfer position in contact with the intermediate transfer belt 50, and is sequentially transferred to the intermediate transfer belt 50 at the primary transfer position. The yellow image forming operation ends after the end of the image is transferred to the intermediate transfer belt 50, and the photoconductor 30 and the intermediate transfer belt 50 stop at the initial position.

During the image formation, the corona charger 34 charges the photosensitive member 30 to -450 V, and the exposure potential of the photosensitive member 30 becomes -50 V. Further, a DC voltage of −250 V is applied to the developing roller 31. Further, a DC voltage of +1.0 kV is applied to the guide pulley 55C and the tension pulley 55D of the intermediate transfer belt 50.

When the formation of the yellow image is completed and the photosensitive member 30 and the intermediate transfer belt 50 are stopped, the drive source of the apparatus main body 1 engaged with the photosensitive member 30
And the carriage 2 is rotated by 90 ° in the direction of the arrow. Thus, the magenta image forming unit 3M is positioned at the image forming position 10 and stopped at the same time as the yellow image forming unit 3Y moves from the image forming position 10. When the magenta image forming unit 3M stops, the drive source of the apparatus main body 1 engages with the magenta photoconductor 30, the image forming unit 3M and the transfer belt unit 5 start operating, and the same image as in the case of yellow is formed. A forming operation is performed. As a result, yellow and magenta toner images are formed on the intermediate transfer belt 50 in a superimposed manner.

The above operation is repeated in the order of cyan and black, and four color toner images are formed on the intermediate transfer belt 50.

The black toner image is transferred to the intermediate transfer belt 50.
After the image is transferred to the secondary transfer roller 9, the secondary transfer roller 9 is brought into contact with the intermediate transfer belt 50 when the head of the image comes to the position of the secondary transfer roller 9, and the recording paper sent from the paper feeding unit 12 is subjected to the secondary transfer. By transporting the toner image between the transfer roller 9 and the intermediate transfer belt 50, the four color toner images are collectively transferred onto the recording paper. At this time, a voltage of +800 V is applied to the secondary transfer roller 9. The recording paper to which the toner image has been transferred passes through the fixing device 15 and is fixed, and is discharged from the discharge roller 18 to the outside of the apparatus.

The toner remaining on the intermediate transfer belt 50 after the secondary transfer is scraped off by the cleaning blade 53 contacting the intermediate transfer belt 50, and the scraped toner is stored in the waste toner case 57 by the screw 52. You.

When the secondary transfer is completed, the intermediate transfer belt 5
0 and the image forming unit 3 stop again, and the carriage 2 rotates by 90 °. Then, the yellow image forming unit 3Y reaches the image forming position 10 again, and is prepared for the next color image forming operation.

[0090]

As described above, according to the present invention,
It is possible to provide a compact image forming unit which has a handle and does not take up a storage space, and an image forming apparatus using the same. Further, according to the present invention, it is possible to provide an image forming unit capable of detecting the remaining amount of toner in a toner storage unit with a simple configuration without lowering detection accuracy, and an image forming apparatus using the same. it can.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is an external perspective view illustrating an image forming unit according to the embodiment of the invention.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a sectional view taken along line CC of FIG. 2;

FIG. 6 is a left side view without the gear cover of FIG. 2;

FIG. 7 is an external perspective view illustrating a state in which the handle of the image forming unit is in a gripping posture according to the embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a state where an operator is replacing the image forming unit according to the embodiment of the present invention.

FIG. 9 is an exploded perspective view showing a carriage and photosensitive member positioning mechanism and drive mechanism of the image forming apparatus according to the embodiment of the present invention.

FIG. 10 is a cross-sectional view of the image forming apparatus according to the embodiment of the present invention, in which the carriage is cut along a plane passing an image forming position.

FIG. 11 is a cross-sectional view illustrating a swing lever portion provided in the developing unit according to the embodiment of the present invention.

FIG. 12 is a right side view of FIG. 2;

FIG. 13 is an external perspective view showing a conventional image forming unit.

[Explanation of symbols]

 2 Carriage 3 Image Forming Unit 5 Transfer Belt Unit 10 Image Forming Position 17 Top Door 30 Photoconductor 31 Developing Roller 35 Developing Unit 37 Photoconductor Unit 39 Toner Hopper 50 Intermediate Transfer Belt 62 Development Drive Body Gear 94 Swing Gear 200 Handle 201 Recess Reference Signs List 202 long hole 203 introduction groove 204 protrusion 205 toner detection case 206 reflecting surface 207 light emitting element 208 light receiving element 209 cleaning member 210 central axis 211 cleaning member main body 212 wing 213 recess 216 locking member

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) G03G 15/08 507 G03G 15/08 507A (72) Inventor Keizo Takeuchi 2-3-3 Shimomeguro, Meguro-ku, Tokyo No. 8 Inside Matsushita Electric Transmission System Co., Ltd. (72) Shigen Mitani 2-3-8 Shimomeguro, Meguro-ku, Tokyo F-term (in reference) 2H030 AA06 AA07 AB02 AD16 BB71 2H071 AA42 BA13 BA24 BA32 DA08 DA15 EA04 2H077 AA12 BA09 BA10 DA15 DA34 DA63 DA81 DA93 GA13

Claims (27)

[Claims] 1. An image forming unit main body having image forming means, and provided on the image forming unit main body so as to be able to take a gripping posture capable of gripping and a non-gripping posture for suppressing gripping, and by an elastic force of itself. An image forming unit including a handle that is constantly urged to take the non-gripping posture. 2. A handle is made of an elastic plate having long holes at both ends, and is attached to a mounting surface of the image forming unit main body via the long holes by a locking member, and abuts on or approaches the mounting surface. 2. A non-grip posture in which the gripper is at least partially separated from the mounting surface.
2. The image forming unit according to 1. 3. An image forming unit used in an image forming apparatus in which a plurality of image forming units are rotatably arranged in a vertical plane, and the plurality of image forming units are sequentially moved to an image forming position to form an image. 2. The image forming unit according to claim 1, wherein the handle is provided on a rotating outer peripheral surface of the image forming unit main body. 4. The image forming unit according to claim 3, wherein the handle is urged to take a non-grasping posture with a stronger elastic force than to take a gripping posture by its own weight. 5. The image forming unit according to claim 3, further comprising a photoconductor and a developing device, wherein the photoconductor is exposed on a rotation outer peripheral surface of the image forming unit body.
2. The image forming unit according to 1. 6. The image forming unit according to claim 5, wherein the handle in the non-grip posture is inside the rotation locus plane of the photoconductor, and the handle in the grip posture is outside the rotation locus plane of the photoconductor. 7. The image forming unit according to claim 1, comprising a photoreceptor unit for supporting a photoreceptor, and a developing unit for supporting a developing device, wherein a handle is provided on the developing unit side. 8. An image forming apparatus, comprising: a unit rotator rotatably supporting a plurality of image forming units in a vertical plane, wherein the plurality of image forming units are sequentially moved to an image forming position to form an image. The image forming unit is provided in the image forming unit main body so as to be able to take an image forming unit main body having an image forming means and a gripping posture capable of gripping and a non-gripping posture for suppressing gripping, and has its own An image forming apparatus, comprising: a handle that is constantly urged by the elastic force so as to take the non-grip posture; and the handle is provided on a rotation outer peripheral surface of the image forming unit main body. 9. An opening / closing door for attaching / detaching the image forming unit is provided above the unit rotating body, and a handle in a gripping posture of the image forming unit mounted on the unit rotating body can be pressed by the opening / closing door. The image forming apparatus according to claim 8, wherein the image forming apparatus is capable of being used. 10. The image forming apparatus according to claim 9, wherein the opening / closing door is provided with a protrusion that can contact a handle in a holding posture of the image forming unit. 11. An image forming apparatus, comprising: a unit rotator for rotatably supporting a plurality of image forming units in a vertical plane, wherein the plurality of image forming units are sequentially moved to an image forming position to form an image. Wherein the image forming unit includes an image forming unit main body, a photoconductor exposed on a rotating outer peripheral surface of the image forming unit main body, and a handle provided on the image forming unit main body. An image forming apparatus, wherein a handle of the image forming unit in a unit rotating body at a replacement position is disposed deeper than the photoconductor when viewed from the front side of the image forming apparatus. 12. An image forming apparatus, comprising: a unit rotator rotatably supporting a plurality of image forming units in a vertical plane, wherein the plurality of image forming units are sequentially moved to an image forming position to form an image. The image forming unit includes a photoreceptor unit that supports a photoreceptor, a developing unit that supports a developing device, and a handle, and the photoreceptor is exposed on a rotating outer peripheral surface of the photoreceptor unit main body. The image forming unit in the unit rotating body at the replacement position of the image forming unit is arranged in the order of the photoconductor unit and the developing unit from the front side of the image forming apparatus, and a handle is provided on the developing unit side. An image forming apparatus characterized in that: 13. The image forming apparatus according to claim 11, wherein replacement of the image forming unit from the rear side of the image forming apparatus is restricted. 14. An image forming apparatus according to claim 13, further comprising an opening / closing door for attaching and detaching the image forming unit above the unit rotating body, wherein the opening / closing door restricts replacement of the image forming unit from the rear side of the image forming apparatus. Image forming apparatus. 15. An image forming unit used in an image forming apparatus in which a plurality of image forming units are rotatably arranged in a vertical plane, and the plurality of image forming units are sequentially moved to an image forming position to form an image. An image forming unit provided with a light-transmitting detection window for detecting a remaining amount of toner on a rotation outer peripheral surface of the image forming unit main body communicating with the toner hopper; 16. The image forming unit according to claim 15, wherein the detection window is located at a corner of the rotation outer peripheral surface of the image forming unit main body. 17. A detection window having a pair of side surfaces facing each other in a recess formed in a toner hopper, and a reflection surface for bending light for detecting a remaining amount of toner is provided near the pair of side surfaces. The image forming unit according to claim 15, wherein: 18. The image forming unit according to claim 15, further comprising a cleaning member for cleaning the detection window. 19. An image forming apparatus, comprising: a unit rotator rotatably supporting a plurality of image forming units in a vertical plane, wherein the plurality of image forming units are sequentially moved to an image forming position to form an image. An image forming apparatus, wherein a light-transmitting detection window for detecting a remaining amount of toner is provided on a rotation outer peripheral surface of the image forming unit main body communicating with the toner hopper. 20. The image forming apparatus according to claim 19, wherein the detection window is located at a corner of a rotation outer peripheral surface of the image forming unit main body. 21. A detection window having a pair of side surfaces facing each other in a recess formed in the toner hopper, and a reflection surface for bending light for detecting a remaining amount of toner is provided near the pair of side surfaces. 20. The image forming apparatus according to claim 19, wherein: 22. The image forming apparatus according to claim 21, further comprising a detection unit that emits and receives light for detecting the remaining amount of the toner, facing the rotation outer peripheral surface of the image forming unit main body. 23. The image forming apparatus according to claim 19, wherein the remaining amount of toner is detected at a position different from the image forming position. 24. The image forming apparatus according to claim 23, wherein the detection of the remaining amount of toner is performed when the detection window is located below a horizontal line including the rotation center of the unit rotator. 25. The image forming apparatus according to claim 23, wherein the detection of the remaining amount of toner is performed when the image forming unit is located at a position facing the image forming position. 26. The image forming apparatus according to claim 23, further comprising a cleaning member for cleaning the detection window, wherein the cleaning of the detection window is performed only at the image forming position. 27. The apparatus according to claim 19, wherein the remaining amount of the toner of the image forming unit of the same color is detected a plurality of times while the unit rotating body rotates a plurality of times, and the remaining amount of the toner is determined based on the result. Image forming apparatus.