JP3116168B2 - Image forming device - Google Patents

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 in which a process material for forming an image, such as an image carrier, is integrated into a cartridge and is detachably mounted.

[0002]

2. Description of the Related Art As one of apparatuses for obtaining a color image by an electrophotographic method, a latent image is formed on a photosensitive drum or a photosensitive belt in accordance with the number of separated colors of an original image and development with a color toner is repeated. In this method, a color image is obtained by superimposing and transferring a color toner image on a drum or a belt. The basic process of this multicolor image formation is described in JP-A-60-75850, JP-A-60-76766, JP-A-60-95456,
Nos. 60-95458 and 60-158475.

In a multi-color image forming apparatus which obtains a color image by such superposition, a plurality of developing devices containing color toners of different colors are arranged on the periphery of a photosensitive member. Generally, a photoconductor is rotated a plurality of times, and a latent image on the photoconductor is developed to obtain a color image.

With respect to such an image forming apparatus, a part of the image forming means is formed into a cartridge for replenishment / replacement when various photosensitive members having a durable life, a developer carrier, a cleaning member and a developer toner are consumed, and the like. the member obtained by integrating the main part of the image forming unit is taken out from the apparatus, walk performs maintenance has been proposed which is configured so as to exchange. In addition, various configurations have been proposed in which a transfer path of a transfer material on which an image is formed by an image forming unit is opened so that the transfer material can be easily taken out during jam processing.

[0005]

However, it is not only troublesome to open the transfer path for the transfer material by inserting a hand into the apparatus after removing the cartridge, but also to erroneously open the transfer path. Inserting a cartridge may cause an accident that may damage the equipment.

The present invention has solved and improved the above points,
It is an object of the present invention to provide an image forming apparatus capable of automatically opening and closing a sheet feeding conveyance path for a transfer material and always accurately setting the sheet feeding direction with respect to an image transfer surface.

[0007]

SUMMARY OF THE INVENTION The above object is, with respect to the apparatus main body made of a unitary construction, the image forming apparatus can be inserted and removed a process cartridge including at least a photoreceptor, an image transfer zone upstream of said process cartridge Beside
Is to the inside of the main body around the rotation axis provided in the main body of the device.
The conveyance path sandwiched between the two movable guide plates
The inner movable guide plate is the outer movable guide
The allowable rotation angle is larger than that of the
When the process cartridge is pulled out of the machine
The transfer path is opened and the process cartridge is opened.
When the cartridge is inserted, it is installed in the process cartridge.
The regulating member contacts the inner movable guide plate and the rotation angle
, And the position of the transfer material feed path is set.

[0008]

1 to 3 show an embodiment of the image forming apparatus of the present invention.

In FIG. 1, reference numeral 1 denotes a flexible photoreceptor belt which is a belt-shaped photoreceptor. The photoreceptor belt 1 is provided between a driving roller 2 and a rotating roller 3 and is driven by the driving roller 2. It is conveyed clockwise.

Reference numeral 4 denotes a support or guide member fixed to the apparatus main body so as to be inscribed in the photoreceptor belt 1.
The photoreceptor belt 1 is brought into a tensioned state by the urging action of the rotating roller 3 to rub the inner peripheral surface thereof against the guide member 4. Therefore, the photosensitive belt 1
The photoreceptor on the outer peripheral surface is always kept at a fixed position with respect to the surface of the guide member 4 even during the conveyance, so that a stable image forming surface can be formed.

Reference numeral 6 denotes a scorotron charger as a charging means;
Denotes a laser writing unit as an image exposure means, and 8 to 11
Is a plurality of developing means or developing devices each containing a developer of a specific color, and these image forming means are disposed opposite to the outer peripheral surface of the photoreceptor belt 1 with the guide member 4 on the back side. Is done.

As the laser writing system unit 7, in addition to the optical system shown in the figure, an optical system or the like in which a light emitting unit and a converging light transmitter are integrated is used.

Each of the developing units 8, 9, 10, and 11 accommodates, for example, each of yellow, magenta, cyan, and black developers, and includes respective developing sleeves that maintain 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 static elimination bar, 13 denotes a cleaning device, and a blade 13A and a toner conveying roller 13B of the cleaning device 13 are kept at positions separated from the surface of the photosensitive belt 1 during image formation. It is pressed against the surface of the photoreceptor belt 1 as shown in FIG.

The process of forming a color image 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 following image forming system. That is, data obtained by a color image data input unit in which an image sensor scans an original image is processed by an image data processing unit to create image data, which is temporarily stored in an image memory. Next, the image memory is taken out at the time of recording and inputted to a recording unit, for example, a color image forming apparatus shown in the embodiment of FIG.

That is, when a color signal output from an image reading apparatus separate from the printer is input to the laser writing unit 7, the laser writing unit 7 generates a color signal from a semiconductor laser (not shown). The laser beam is rotated by a driving motor 7A.
B, and is rotated and scanned by the mirror B through the fθ lens 7C.
The light path is bent by D, 7E, and 7F, and projected on the peripheral surface of the photoreceptor belt 1 to which a charge is applied in advance by a 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. Therefore, a latent image corresponding to the first color is formed on the peripheral surface of the photosensitive belt 1 by the main scanning by the laser beam and the sub-scanning by the conveyance of the photosensitive belt 1. This latent image is yellow (Y) of the developing means.
Is developed by the developing device 8 loaded with the toner (developing medium), and a toner image is formed on the belt surface. The obtained toner image passes under the cleaning device 13 as a cleaning means separated from the peripheral surface of the photoreceptor belt 1 while being held on the belt surface, and enters the next copy cycle.

That is, the photoreceptor belt 1 is charged again by the charger 6, and then the second color signal output from the signal processing unit is input to the writing system unit 7, and the first color signal In the same manner as in the above case, writing is performed on the belt surface to form a latent image. The latent image is developed by the developing device 9 loaded with magenta (M) toner as the second color.

The magenta (M) toner image is formed in the presence of the previously formed yellow (Y) toner image.

Reference numeral 10 denotes a developing device having cyan (C) toner, and forms a cyan (C) toner image on the drum surface based on a control signal generated by a signal processing unit.

Reference numeral 11 denotes a developing device having a black toner, which forms a black toner image on the belt surface by the same processing. A DC or AC bias is applied to each sleeve of each of these developing units 8, 9, 10 and 11, and a jumping development is performed by a two-component developer as a visualizing means, and the photosensitive member whose substrate is grounded The belt 1 is developed in a non-contact manner. As the development, non-contact development using a one-component developer can also be used.

The color toner image formed on the peripheral surface of the photoreceptor belt 1 is transferred to a transfer material sent from a paper feed cassette 14 via a paper feed path 15 at a transfer section.

That is, one of the uppermost layers of the transfer material accommodated in the paper feed cassette 14 is carried out by the rotation of the paper feed roller 17, and the image formation on the photosensitive belt 1 is synchronized with the image formation via the paper feed roller 17. And is supplied to the transfer device 12.

The transfer material having undergone image transfer and charge elimination is surely separated from the photoreceptor belt 1 which suddenly changes its direction along the rotating roller 3 and is moved upward through an attraction type conveyance belt 17A. In the opposite direction, the image is welded by the fixing roller 18, and then discharged onto a tray formed on the upper lid 20 via the discharge roller 19.

On the other hand, the photoreceptor belt 1 after the transfer to the transfer material is further conveyed, and the remaining toner is removed by the cleaning device 13 in which the blade 13A and the toner conveying roller 13B are pressed against each other. Then, the blade 13A is separated again. After a short time, the toner supply roller 13B smoothes the toner accumulated on the tip of the blade 13A, and then the toner supply roller 13B is separated to start a new image forming process.

The photosensitive drum 1, the charging device 6, the respective developing devices and the cleaning device 13 are incorporated into an independent process cartridge 30 as a process material for image formation, integrated and attached to and detached from the apparatus main body.

The paper feed path 15 is composed of a movable guide plate 151 and a movable guide plate 152 rotatable about a shaft 151A and a shaft 152A shown in FIGS. 2 and 3, respectively.

On the side of the movable guide plate 151, a pair of drive rollers 171 constituting the above-described paper feed roller 17 is provided. On the side of the movable guide plate 152, a pair of driven rollers 172 pressed against the drive roller 171 are provided. is set up.

Each of the driven rollers 172 has a support shaft guided by a guide groove 173 so as to be movable in a direction perpendicular to the conveying surface, and a torsion spring 174 locked at both ends.
Is strongly urged in the direction of the conveying surface by the reaction force, and is brought into pressure contact with the drive roller 171.

Further, the movable guide plate 152 is
While maintaining the pressure contact state of 72, the torsion spring 154 urges the clockwise direction, and the upper end thereof is stopped by contacting the regulating member 30B on the front surface of the process cartridge 30.

On the other hand, the movable guide plate 151 is moved by the action of a compression spring 156 attached to the apparatus body.
Thus, the functions of guiding and transporting the transfer material by the paper transport path 15 and the paper feed roller 17 described above are exerted.

That is, the transfer material carried out of the paper supply cassette 14 is carried into the paper supply conveyance path 15 by the paper supply roller 17, abuts against the stop member 180, and is temporarily stopped in a slipped state.

When the solenoid SL is turned on by a signal synchronized with the image device on the photosensitive belt 1,
When the stop member 180 moves the plunger PL, the tension spring 1
It rotates counterclockwise around the shaft 181 against the shaft 82 and retracts from the transport surface. Therefore, the transfer material is again conveyed from the slipping state by the paper feed roller 17, is fed to the image transfer area, and receives the transfer of the image to a predetermined position.

On the other hand, the process cartridge 30 is slid and inserted while being supported by a pair of guide rails 30A provided on the apparatus main body, and a pair of reference holes H opened on the front side thereof are fixed to the apparatus main body. It is placed at a predetermined mounting position by engaging and contacting the reference pin P, and is fixed at that position by its own weight and the action of a click device (not shown).

Accordingly, as shown in FIG. 3, the process cartridge 30 can be pulled out obliquely to the upper right along the guide rail 30A and can be removed from the apparatus main body. As a result, the movable guide plate 152 is attached to the regulating member 30B. Is retracted, and is rotated clockwise by the urging of the torsion spring 154 to come into contact with the stopper 155 and stop.

With the rotational movement of the movable guide plate 152 in the clockwise direction, the movable guide plate 151 is also rotated clockwise by the action of the compression spring 156 to come into contact with the stopper 157 and stop.

By setting the rotation angle of the movable guide plate 151 to the minimum necessary, while making the rotation angle of the movable guide plate 152 as large as possible, the transfer material transfer surface can be largely opened.

As a result, maintenance such as removal of jammed paper and cleaning / inspection of the conveyance surface can be easily performed. Further, when the process cartridge 30 is mounted, the transfer material can be fed from the correct direction to the image transfer area. It becomes possible.

[0040]

According to the present invention, the feeding path of the transfer material is automatically opened and closed by the attachment and detachment of the process cartridge to / from the apparatus main body. At the same time, an image forming apparatus has been provided which is capable of obtaining a high-quality image by feeding a transfer material accurately in an image transfer area.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus of the present invention.

FIG. 2 is a detailed view of a paper feed path with a process cartridge mounted.

FIG. 3 is a detailed view of a sheet feeding conveyance path when a process cartridge is removed.

[Explanation of symbols]

1. Photoreceptor belt 6. Charger 8, 9, 10, 11 ...
Developing device 12 Transfer device 13 Cleaning device 14 Paper cassette 15 Paper feed path 17 Paper feed roller 30 Process cartridge 30 A Guide rail 30 B Regulators 151, 15
2… Movable guide plate 154,174… Torsion spring 156… Compression spring 171… Drive roller 172… Driving roller 173… Guide groove 180… Stop member P… Reference pin H… Reference hole

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Masakazu Fukuchi Examiner, Konica Co., Ltd., 2970 Ishikawacho, Hachioji-shi, Tokyo (56) References JP-A-62-299868 (JP, A) Hei 1-266559 (JP, A) JP-A-63-40173 (JP, A) Japanese Utility Model Application Hei 1-169554 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15 / 00 550 G03G 15/00 510-516 G03G 15/00 526 G03G 12/16-21/18

Claims (1)

(57) [Claims] 1. An apparatus body having an integral structure,
In an image forming apparatus in which a process cartridge including at least a photoreceptor can be inserted and detached, the process cartridge has an
Energizes inward of the main unit around the rotation axis provided in the main unit
A conveyance path sandwiched between the two movable guide plates
And the inner movable guide plate is more permissive than the outer movable guide plate
The process cartridge is pulled out of the apparatus main body.
When the process cartridge is inserted , the process path is opened.
A regulating member provided on the inner cartridge
An image forming apparatus for controlling a rotation angle by contacting a transfer plate and setting a position of a sheet feeding conveyance path for a transfer material.