JP2955871B2 - Image forming device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to an image forming method in which a toner image is formed on an image forming body by an electrophotographic method, and the toner image is transferred onto transfer paper to obtain an image. It concerns the device.

2. Description of the Related Art There are various types of color image forming apparatuses. In general, a belt-shaped image forming body (also referred to as a photoreceptor belt) is stretched between two axes, and each of the belts extends along a lower side thereof. A plurality of developing devices containing toners of different colors are arranged, and while the photoreceptor belt is rotated a plurality of times, a latent image is formed on the photoreceptor belt in accordance with the number of color separations of the original image and the development is performed. After a color image is formed by performing development by a group of developing devices, the color image is transferred onto a transfer paper fed from a paper feeding cassette in a cassette housing chamber provided below the developing device group to obtain a color copy. It has become.

Unlike the photoreceptor drum, the photoreceptor belt of such a color image forming apparatus can make a U-turn with a small curvature, so that it can run flat and has an advantage that space can be effectively used. In addition, by providing a separation pole of the transfer paper after transfer at the small-diameter curvature portion that makes a U-turn, there is an advantage that the transfer paper can be separated well.

[Problems to be solved by the invention]

In the case of the above color image forming apparatus, the photoreceptor belt and the cassette accommodating chamber are arranged in layers with the developing device group interposed therebetween. Are provided along the inner surface of one side wall of the apparatus main body so as to go around the outside of the developing device group. On the other hand, the opening / closing lid of the cassette storage chamber is provided on the side wall of the main body opposite to the sheet feeding path and the sheet feeding means, so that the sheet feeding cassette can be inserted in the same direction as the sheet feeding direction.

Therefore, in addition to the opening / closing lid of the cassette storage chamber, it is necessary to provide a jam processing lid for removing jammed paper generated in the paper feeding path on the main body side wall on the paper feeding path side,
In addition, if the photoreceptor belt and the developing unit are integrated into a cartridge, it is necessary to provide a large opening for attachment and detachment, and if the unit has a manual paper feed function, it must have a paper feed port. Therefore, there has been a problem that the production cost is increased, the operation and work are performed over two or more surfaces of the apparatus, the efficiency is reduced, and the floor area for installation is increased. In recent years, Japanese Unexamined Patent Publication No.
63-244058, JP-A-63-244059, JP-A-63-244064
As disclosed in Japanese Unexamined Patent Publication No. Hei 1-179168, it has been proposed that processing can be performed from the same direction.
Devices intentionally developed and devised so that all of them can be processed for maintenance and maintenance work have not yet been provided.

An object of the present invention is to provide an image forming apparatus configured so that all of the above operations and operations can be performed on the same side of the apparatus as a result of solving and improving this point.

[Means for solving the problem]

The object is to provide, on one side surface of the apparatus main body, a transfer paper transport path that can be opened at least partially, and along the transfer paper transport path, a discharge unit, a fixing unit, a transfer unit, and a paper supply unit. , An electrophotographic image forming apparatus in which a paper discharge tray is provided on an upper surface of the apparatus main body, wherein a lower main body and at least a part of the transfer paper conveyance path are openable and the lower main body is arranged. An upper body provided to be openable with respect to the main body, and the transfer means being detachable from the one side from the one side when the upper body is open, and the transfer means when the upper body is closed. A process cartridge provided at least in the upper body, including at least a photoconductor and a developing device, and a lower part of the lower body below the process cartridge. Said Provided detachably from the side, is achieved by an image forming apparatus characterized by having a paper feed cassette for accommodating transfer paper is fed by said feeding means.

〔Example〕

Next, the present invention will be described based on an embodiment shown in the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a flexible photoreceptor belt as a belt-shaped image forming member. The photoreceptor belt 1 is stretched between a driving roller 2 and a driven roller 3, and is conveyed clockwise.

Reference numeral 4 denotes a guide member fixed to the apparatus main body so as to be inscribed in the lower side portion of the photoreceptor belt 1, and reference numeral 5 denotes a tension roller for making the photoreceptor belt 1 in contact with the guide member 4 in tension. The guide member 4 and the tension roller 5 make it possible to form a stable image forming surface on the photosensitive belt 1.

Reference numeral 6 denotes a scorotron charger as charging means, and reference numeral 7 denotes a laser writing system unit as image exposure means. In addition to the optical system shown in the figure, the laser writing system unit 7 can use an optical system or the like in which a light emitting unit and a converging light transmitter are integrated.

Reference numerals 8, 9, 10, and 11 denote developing devices as a plurality of developing means, each containing a developer of a different color, for example, each of yellow, magenta, cyan, and black developers. Reference numeral 4 denotes a photoreceptor belt that is in contact with the photoreceptor belt 1. Each of these developing units 8 to 11 is provided with a developing sleeve 8A, 9A, 10A, 11A for keeping a predetermined gap from the photosensitive belt 1.
It has a function of visualizing a latent image on the photoreceptor belt 1 by a non-contact developing method. Unlike the contact development, the non-contact development has an advantage of not hindering the movement of the photosensitive belt.

Reference numeral 12 denotes a transfer unit, 12A denotes a charge removing bar, and 13 denotes a cleaning device. The blade 13A of the cleaning device 13 and the toner conveying roller 13B are maintained at positions separated from the surface of the photoreceptor belt 1 during image formation, and only during cleaning after image transfer after image transfer as shown in FIG. It is pressed against the surface.

The process of the color image forming apparatus by the color image forming apparatus is performed as follows.

First, the formation of a multicolor image according to the present embodiment is performed according to the image forming system shown in FIG. That is, an original image is obtained at a color image data input unit (a) scanned by an image sensor, and the data is subjected to arithmetic processing at an image data processing unit (b) to create image data and temporarily stored in an image memory (c). Is done. Next, the image memory is taken out at the time of recording and inputted to a recording section (d), for example, to the color image forming apparatus shown in the embodiment of FIG. That is, when a color signal output from an image reading device separate from the printer is input to the laser writing unit 7, a laser beam generated by a semiconductor laser (not shown) in the laser writing unit 7 is used. Is rotationally scanned by a polygon mirror 7B rotated by a drive motor 7A, and is mirrored through an fθ lens 7C.
The optical path is bent by 7D and 7E, and is projected on the peripheral surface of the photoreceptor belt 1 to which a charge has been previously given by the charger 6 serving as a charging means to form a bright line.

On the other hand, when the scanning is started, the beam is detected by the index sensor, the modulation of the beam by the first color signal is started, and the modulated beam scans the peripheral surface of the photosensitive belt 1. Accordingly, a latent image corresponding to the first color is formed on the peripheral surface of the photoreceptor belt 1 by the main scanning by the laser beam and the sub-scanning by the conveyance of the photoreceptor belt 1. This latent image is developed by the developing device 8 in which yellow (Y) toner (visual medium) of the developing means is loaded, and a toner image is formed on the drum surface. The obtained toner image passes under the blade 13A of the cleaning device 13 separated from the peripheral surface of the photoreceptor belt 1 while being held on the drum surface, and enters the next copy cycle.

The photoreceptor belt 1 is charged again by the charger 6,
Next, the second color signal output from the signal processing unit is input to the writing unit 7, and writing is performed on the drum surface in the same manner as in the case of the first color signal described above to form a latent image. The latent image is developed as a second color by the developing device 9 loaded with magenta (M) toner. The magenta (M) toner image is formed in the presence of the previously formed yellow (Y) toner image. In the same manner, the developing device 10 having the cyan (C) toner
Is formed, and a black toner image is formed on the belt surface by the developing unit 11 having black toner.

A DC or AC bias is applied to each sleeve of each of the developing devices 8, 9, 10, and 11, a jumping development is performed by a two-component developer as a visualization means, and a photoreceptor belt on which a base is installed. No. 1 is developed in a non-contact manner. Incidentally, non-contact development using a one-component developer can also be used as the development.

As described above, the color toner image formed on the peripheral surface of the photosensitive belt 1 is transferred to a transfer sheet. The transfer paper is fed to a paper feed cassette 1 in a cassette storage chamber 140 below the developing devices 8 to 11.
From 4, the paper is fed one by one from the uppermost layer to the paper feed path 15 by the friction of the paper feed roller 16, and is supplied to the transfer device 12 via the timing roller 17 at the same time as the image formation on the photosensitive belt 1. Regarding the transfer paper separation means, the separation roller 16
A is used.

As described above, the transfer paper supplied to the transfer unit 12 and subjected to image transfer and charge removal is reliably separated from the photoreceptor belt 1 which sharply (small-diameter curvature) changes direction along the drive roller 2. After the image is welded upward by the fixing roller 18, the image is discharged onto the paper output tray 20 via the paper output roller 19 and stacked.

On the other hand, the photoreceptor belt 1 after the transfer to the transfer paper is further conveyed, and the remaining toner is removed in the cleaning device 13 in which the blade 13A and the toner conveying roller 13B are pressed against each other. After the cleaning is completed, the blade 13A is separated again, and a little later, the toner transport roller 13B smoothes the toner accumulated at the tip of the blade 13A, and then separates the toner transport roller 13B to start a new image forming process.

FIG. 1B is a partially enlarged view of the paper feed path of the color image forming apparatus shown in FIG. 1A. When the paper is fed from the manual guide plate 21, transfer paper or special paper such as OHP paper is transported by the transport guide (a) 1.
00a and the conveyance guide (b) 100b, rises along the conveyance guide (d) 101d through the junction 101c where the cassette paper feeding conveyance guide (c) 101a intersects, and a slight gap a ( a ≧ 0, preferably 0.2 to 3 mm), the paper feed path 15 formed by the cartridge side plate 310 which is one side plate of the housing of the cartridge 30 which is inserted and connected to the apparatus main body, and the transport guide (a) 100a. The transfer paper is conveyed in the direction of the transfer device 12 without being caught by each conveyance guide end or the cartridge side plate bottom 310a.

Similarly, the transfer paper fed from the paper feed cassette 14
After passing through 101c, the horizontal cover 101 has a slight gap b (b ≧ 0, preferably 0.2 to 3 mm) with the normal direction above it.
At a position facing the transport guide (d) 101b.
The transfer paper is conveyed to the paper feed path 15 without being caught at the guide conveyance end. In either case, the transfer paper is transported through a paper feed path 15 shared by one side as a transport guide (a) 100a and the other side of the cartridge housing as a transport guide.

The photoreceptor belt 1 and each developing unit are integrated into a cartridge 30 including one member forming a pair of a charging unit 6, a cleaning device 13, a paper feeding path 15 as a transfer material conveying path, and a timing roller 17. The cartridge is collectively attached to and detached from the apparatus main body by a cartridge insertion guide (not shown) provided in the upper housing.

When the cartridge 30 is mounted on the apparatus main body, each of the tray transport pipes 1 of the corresponding toner hopper 150 is
51 is automatically connected to a state where toner supply is performed.

The apparatus is a paper feeding means for feeding the transfer paper to the paper feeding path 15, and an openable manual feed guide plate 21 on a side portion of the apparatus main body.
And a second paper feeding means for automatically feeding paper from the paper feeding cassette 14 described above.

On the other hand, the apparatus body has a clamshell structure that can be divided into upper and lower parts, and the cartridge 30 and the fixing roller 18,
The upper body containing the paper discharge roller 19 can be opened and held clockwise with the hinge 160 shown in FIG. 1 as a fulcrum with respect to the lower body containing the laser writing unit 7 and the cassette storage chamber 140, etc. It has become.

FIG. 3 shows a state in which the paper feed path 15 is opened only by opening the upper body, and the cartridge 30 can be inserted into and removed from the upper body by sliding the cartridge 30 from the left along the inclination as shown by the arrow A. 1 shows an embodiment of the present invention.

FIG. 4 shows a second embodiment in which the pressure contact surface of the fixing roller 18 can be simultaneously opened in addition to the sheet feeding path 15, and shows a clamshell type as in the first embodiment. Since the opening of the paper supply path 15 and the insertion / removal of the cartridge 30 and the paper supply cassette 14 are enabled only by using the clamshell type as in the first embodiment, the left side of the main body of the apparatus can be used. On the surface, a support shaft 161A as shown in FIG. 4 is used instead of the manual feed guide plate 21 in the first embodiment.
By providing the horizontal cover 161 that opens and closes in the horizontal direction with the fulcrum as a fulcrum, the toner recovery container 170 and the like can be supported inside the horizontal cover 161, and the waste toner from the cleaning device 13 is transported through the flexible toner recovery pipe. They can be collected. As shown in FIG. 4, the toner collecting container 170 for collecting the toner from the cleaning device 13 is a left end or a right end (not shown) of the horizontal cover 161 that opens and closes as shown.
And a replaceable waste toner collecting unit can be formed.

Toner collection container 170 and collected toner pipe (not shown)
Can be appropriately reached by using a mechanism for engaging and disengaging the toner transport pipe 151 for supplying toner, which will be described later, and each developing unit (illustrated in FIGS. 6A and 6B).

Also, as shown in FIGS. 4 and 5, the transport guide (d)
By providing the cartridge 101b integrally with the cartridge 30, it is also possible to constitute a cartridge that can be inserted into and removed from the apparatus main body.

FIG. 5 shows a third embodiment in which the entire left side surface of the apparatus main body is provided with a lateral cover 162 which can be opened and closed with a support shaft 162A as a fulcrum.
In this case, since the inside of the apparatus main body can be largely opened together with the opening of the upper main body as described above, operations such as jam processing, inspection of each part, and cleaning can be performed more easily. The Rukoto.

FIG. 6 shows an example of a mechanism for engaging and disengaging the toner transport pipe 151 and each developing unit when the cartridge 30 is inserted into and removed from the apparatus main body in the case of the developing unit 8, and FIG. FIG. 6 (B) is a side view, and FIG.

A rectangular flange plate 151A is provided at the lower end of the toner conveying pipe 151.
Are integrally formed, and a shutter plate 152 having a guide pin P1 that engages with a pair of elongated holes 151B provided in the flange plate 151A is slidably supported on the lower surface of the flange plate 151A.

When the cartridge 30 is not mounted, the shutter plate 152 slides leftward by the urging force of a pair of tension springs 153 stretched between the guide pin P1 and the fixing pin P2 on the flange plate 151A, and slides to the left of the toner conveying pipe 151. The toner drop hole 151C is blocked to prevent toner from dropping.

On the other hand, the developing device 8 has a shutter plate having a pair of claw portions 154A that engage with guide grooves 8B provided on both sides of the toner receiving portion.
154 is slidably supported on the upper surface thereof, and slides rightward by the urging of a tension spring 155 stretched between the claw portion 154A and the fixing pin P3 on the toner receiving portion when the cartridge 30 is not mounted. Toner receiving hole in the toner receiving section
8C is shielded to prevent scattering and outflow of toner.

When the developing device 8 is moved in the direction indicated by the arrow B by inserting the cartridge 30 into the apparatus main body, the rising portion of the shutter plate 154 is located on the receiving portion next to the end of the flange plate 151A of the toner conveying pipe 151. The pressing pins P4 of the cartridge 3 come into contact with the rising portions of the shutter plate 152, respectively.
0 at the same time as the completion of the mounting of the toner drop port 151 as shown in the figure.
C and the toner receiving port 8C are fully opened so that toner can be supplied.

When the cartridge 30 is pulled out from the apparatus main body, the shutter plates 152 and 154 automatically return to the initial positions, and again shield the toner falling port 151C and the toner receiving port 8C, respectively.

The mechanism for engaging and disengaging each developing device with respect to the toner conveying pipe 151 is three-dimensionally arranged at different positions in the direction perpendicular to the plane of FIG. 1 for each developing device.
It is configured such that when the 30s are inserted and removed, the engaging and disengaging actions are performed without interfering with each other.

FIG. 7 shows transfer paper storage means for mounting the paper feed cassette 14 in the apparatus main body.

The cassette accommodating chamber 140 includes a pair of guide members 141 having vertical grooves 141A opposed to each other on the inner surface thereof, and an elevating member 143 holding a lifting member 142 in the vertical grooves 141A engages a bent portion thereof. It is supported so that it can slide up and down by joining. The push-up members 142 are provided in a pair in a direction perpendicular to the paper surface, and are urged upward by compression springs 144, respectively.

Further, a pair of swing levers 146 each having a rotating roller 145 pivotally mounted thereon are rotatably mounted on the cassette storage chamber 140 with a support shaft 147 as a fulcrum. The engagement pin 143A on the outer side is sandwiched.

When the paper feed cassette 14 is mounted, the rocking lever 146 is in a position where the swing lever 146 is rotated counterclockwise by the urging of the torsion spring 148, so that the elevating member 143 slides upward and the push-up member 142 is moved The transfer paper loaded on the bottom plate 14A is pressed against the paper feed roller 16 by the urging of the compression spring 144.

The push-up member 142 rises in accordance with the decrease in the number of transfer papers, and keeps the uppermost transfer paper pressed against the paper feed roller 16 at all times.

The paper cassette 14 slides in the direction of arrow C via a handle 14B and is horizontally inserted into and removed from the cassette storage chamber 140. Press and push down to swing lever 1
Turn 46 clockwise.

As a result, it is possible to insert and remove the sheet cassette 14 from the horizontal direction by lowering and retracting the upper end of the lifting member 142 to a position where it does not interfere with the bottom surface of the sheet cassette 14 by sliding the lifting member 143 downward. Become.

In the cassette storage chamber 140, the above-described transfer paper storage means can be further added to simultaneously store a plurality of paper feed cassettes storing transfer papers of different sizes.

〔The invention's effect〕

According to the present invention, a part of the transfer paper transport path is opened by opening the upper main body of the apparatus main body, and the opening of the transfer paper feed path is used to exchange the process cartridge for accommodating the photoconductor and the developing device. The cassette can be inserted / removed on the same side as the cassette, so that the upper body can be opened and a large space can be formed, making it very easy to replace the process cartridge. The unit is designed to be easily attached and detached from one side of the main unit, so that copying operations, paper feeding operations, and various types of maintenance can be performed on one side of the unit. An image forming apparatus which is easy to inspect and does not require a large floor area for installation and has excellent practicability has been provided. The transfer paper transport path for transporting the transfer material in a substantially straight line from below can also be used to reduce the size of the apparatus, without requiring a large floor area, and the transfer material can be satisfactorily transported by the substantially straight transport. In addition, by opening a part of the transfer paper transport path along with the opening of the upper main body, an image forming apparatus in which jam clearance is extremely easy is provided.

[Brief description of the drawings]

FIG. 1A is a cross-sectional view of the color image forming apparatus of the present invention, FIG. 1B is a cross-sectional view of a main part of a transfer material conveying path, FIG. 2 is a block diagram showing an image forming system, and FIG. Figures to Fifth
Figures are explanatory views showing the configuration of the main body of the apparatus, and Figs. 6 and 7 are a side view and a plan view showing a main part of the apparatus. DESCRIPTION OF SYMBOLS 1 ... Photoreceptor belt, 4 ... Guide member 6 ... Charging device 7 ... Laser writing system unit 8, 9, 10, 11 ... Developing device, 12 ... Transfer device 13 ... Cleaning device 14 ... Supply Paper cassette, 14A Bottom plate 14B Handle 15 Feeding path 16 Feeding roller 16A Separating roller 17 Timing roller 18 Fixing roller 19 Discharge roller 21 Manual feed guide plate, 22 Manual feed guide roller 30 Process cartridge 140 Cassette storage chamber 142 Push-up member 143 Lifting member 145 Rotating roller 146 Swing lever 150 Toner hopper 151: toner transport tube, 151C: toner drop port 152, 154: shutter plate, 161, 162: horizontal cover

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-43170 (JP, A) JP-A-1-99064 (JP, A) JP-A-1-172127 (JP, A) 159474 (JP, U) Japanese Utility Model Showa 62-109164 (JP, U) Japanese Utility Model Showa 62-170944 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 15/00 550 G03G 21/16-21/18 B41J 29/00

Claims (2)

(57) [Claims] An apparatus has a transfer paper conveyance path on one side of the apparatus main body, the transfer paper conveyance path being at least partially openable, and along the transfer paper conveyance path, a paper discharge means, a fixing means, a transfer means, and a paper supply means. Are arranged in order from the top, and a paper ejection tray is provided on the upper surface of the apparatus main body. An electrophotographic image forming apparatus comprising: a lower main body; at least a part of the transfer paper transport path being openable; An upper body provided to be openable with respect to the main body, wherein the transfer is detachable from the one side from the one side when the upper body is open, and the transfer is performed when the upper body is closed. A process cartridge including at least a photoreceptor and a developing device provided on the upper body so as to be located on the side opposite to the one side surface side with respect to the means; and a lower part of the process cartridge and a lower body. ,Previous An image forming apparatus, comprising: a paper feed cassette detachably provided from the one side surface for storing transfer paper fed by the paper feeding means. 2. An image forming apparatus according to claim 1, wherein said process cartridge has a guide for transferring a transfer sheet between said sheet feeding means and said transfer means.