JPH04121757A - Image forming device - Google Patents

Abstract

PURPOSE:To surely execute an image forming process and to obtain a high quality image by providing a positioning part supporting and fixing a process cartridge at a normal device position where an image can be formed, on the supporting member of a device main body. CONSTITUTION:The oblong parts 361A and 361B of the upper parts and the the guiding members 38A and 38B are integrally constituted with the bottom plate member 39 of the lower part and a positioning holding member 391, so that the attaching positions of the supporting members 36A and 36B are stabilized with excellent precision. Therefore, the precision of the stopping holding position of the cartridge 15 at the first position is sure, and a relative position with respect to an optical system unit 22 is accurate. On the other hand, even if the insertion/uninsertion of the cartridge 15, and the attachment/detachment of the optical system unit 22 are carried out, the reproducibilities of respective stopping positions are excellent and relative position precision can not be fluctuated. On the other hand, when the cartridge 15 is attached to the device main body, the cartridge 15 is held, and turned to the opening part of the device main body, and driving rollers shafts 18A and 18B are mounted and slid along the up surfaces of the guiding members 38A and 38B, in the opened state of the front cover.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus that forms a toner image on an image carrier using an electrophotographic method and transfers it onto a transfer material to obtain an image. . In particular, the present invention relates to an image forming apparatus such as a printer, a copying machine, a facsimile machine, etc., which is provided with a removably attached process cartridge in which an image carrier and at least one image forming means such as a developing means and a cleaning means are integrated into a unit.

[Background of the invention]

2. Description of the Related Art As image forming apparatuses such as printers and copying machines become smaller, lighter, and more sophisticated, image forming apparatuses are becoming more dense and complex.

On the other hand, even operators who are general users can easily maintain and
In order to facilitate management, an image forming apparatus has been developed that includes a process cartridge in which an image carrier and at least one image forming means such as a developing means and a cleaning means are integrated into a unit.

In image forming apparatuses such as printers and copying machines equipped with this process cartridge, when the image bearing member inside the process cartridge becomes worn out or deteriorated, the process cartridge itself can be replaced, allowing operators without specialized knowledge to image the image by themselves. This makes it possible to easily maintain and manage the forming device. To this end, a guide member for the process cartridge is provided in the main body of the apparatus, and the process cartridge can be loaded by simply inserting the process cartridge along the guide member so as to obtain an optimal image.

In such cases, in conventional devices, the insertion direction of the process cartridge and the loading direction of the transfer material were perpendicular to each other, so the handling direction of the process cartridge and the handling direction of the transfer material were different, which made these operations cumbersome. However, the space constraints for installing the image forming apparatus inevitably become large. Furthermore, in the case of maintenance, it was necessary to take up a large work space.

In order to solve these drawbacks, Japanese Patent Application Laid-Open No. 61-279870 was proposed. In other words, by matching the loading direction of the transfer material with the loading/unloading direction of the process cartridge provided in the openable upper housing, handling and operation of consumables is made easier and work space constraints are reduced. Image forming apparatuses have been proposed.

[Problem that the invention seeks to solve]

However, the image forming apparatus disclosed in Japanese Unexamined Patent Publication No. 61-279870 has a two-part upper and lower housing that can be opened and closed around a rotating shaft, and the upper housing can be opened and closed in an open state. The process cartridge is removable, and a transfer material conveying means and a laser beam scanner are provided inside the lower housing.

In the image forming apparatus described above, the process cartridge in the upper housing and the laser beam scanner in the lower housing are respectively set at different positions in the upper and lower housings and are rotatable, so that in the closed image forming state, This has the disadvantage that relative positioning becomes extremely unstable and accurate image formation cannot be obtained.

Further, in order to ensure the above-mentioned relative positioning, complicated structures and operations are required.

Further, an image forming apparatus having a two-part structure in which a laser beam scanner is attached to an upper housing and a process cartridge is attached to and removed from a lower housing has the same problem as described above.

The present invention has been made to solve the above-mentioned drawbacks.
SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus in which a process cartridge can be moved and replaced with simple operations and is easy to maintain. That is, the present invention provides an image forming apparatus that can easily and safely perform work to handle paper jams and the like that occur on the paper transport path within the image forming apparatus, as well as inspect and repair the inside of the apparatus.

Another object of the present invention is to stably maintain the relative positioning accuracy between a process cartridge that can be inserted into and removed from the apparatus main body and a laser writing optical system unit (laser beam scanner), and to reliably perform an image forming process. However, it is an object of the present invention to provide an image forming apparatus that can obtain high-quality images.

[Means for solving problems]

The above object is to provide a process cartridge in which an image forming means including an image bearing member on which an electrostatic latent image is formed is integrated into a unit and can be freely inserted into and removed from the main body of the apparatus; and a laser writing optical system unit that converts the image information supplied by the
In the image forming apparatus, a positioning part that supports and fixes the process cartridge in a normal loading position where image formation is possible, on a support member of an apparatus main body that supports and positions and fixes the laser writing optical system unit in a predetermined position. This is achieved by an image forming apparatus characterized in that it is provided with.

Further, the image forming apparatus of the present invention is characterized in that the support member is provided with a guide portion that supports the process cartridge 7 and allows it to be freely inserted and removed.

〔Example〕

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

FIG. 1 shows a main cross section of a color printer to which the present invention is applied, viewed from the left side. The main body 10 of the apparatus is surrounded by an operation panel 11, an openable and closable upper cover 12, a toner supply cover 13, a front cover 14, etc. on the front side, and a removable process cartridge 15 and a paper feed power center are installed inside. 16 are provided.

FIG. 2 is a sectional view of the process cartridge 15. The process cartridge 15 includes a photoreceptor belt 17 and a developing device 2.
3. Charger 211 Consists of cleaning device 25 and the like.

In the figure, the photosensitive belt +7, which is an image carrier, is a flexible belt with a photosensitive layer such as an organic photoconductive layer coated on its surface, and is stretched between a driving roller 18 and a driven roller 19. There is. The drive roller 18 (described later) rotates and conveys the photoreceptor belt 17 in a clockwise direction via a drive gear meshing with a gear provided in the main body IO of the apparatus. Also, spacing members 20a and 20b.

20c and 20d, a plurality of developing devices 23a,
The distances between the photoreceptor belts 23b, 23c, and 23d and the photoreceptor belt 17 are kept constant, making it possible to stably form good images.

A charging means, an exposure means, a developing means, a transfer means, and a cleaning means are arranged around the photoreceptor belt 17.

The charging means is provided to uniformly charge the photosensitive layer on the surface of the photoreceptor bell 1-17 with a predetermined polarity, and is an existing charger 2I such as a corona charger or a scorotron charger, and is an organic photoconductive charger. For layer (OPC) photoreceptors, a scorotron charger is preferably used.

The developing means includes a plurality of developing units 23a each containing different color developers, for example, yellow, magenta, cyan, and black color toners (developer).

23b, 23c, and 23d. Each of these developing devices 2
3a to 23d are provided with developing sleeves 231a to 231d that maintain a predetermined gap with the photoreceptor belt 17, and stirring screws 2328 to 232d that stir the toner of each color, so that the electrostatic latent image on the photoreceptor belt 17 does not come into contact with the toner image. It has the function of being visualized using a developing method. This non-contact development method is
Unlike the contact development method, since the toner image formed on the photoreceptor belt 17 is not damaged and the movement of the photoreceptor belt 17 is not hindered, a good color image can be obtained. The developing means is not limited to color development using four different color toners as in this embodiment, but may also use monochromatic, two-color, or three-color toners, and in this case, the developing means may be used for color development using toner of four different colors. It is sufficient to arrange only one developer around the photoreceptor belt 17.

The cleaning means 25 includes a cleaning blade 251
During the image forming process, the photoreceptor belt 17
It is maintained at a position spaced apart from the surface of the photoreceptor belt 17, and is provided so as to come into pressure contact with the surface of the photoreceptor belt 17 to clean the photoreceptor belt 17 only during cleaning after transferring the toner image to the transfer material.

The toner collection box 26 is for collecting and storing the residual toner on the photoreceptor belt 17 removed by the cleaning means 25 through the toner collection pipe 262 by the waste toner screw 252, and is used to collect and store the residual toner on the photoreceptor belt 17 that has been removed by the cleaning means 25. It may be made separate or detachable.

In this embodiment, the image forming section of the printer described above includes a photoconductor bell (17), a charger 211, developing devices 23a to 23d1 containing toner of each color, and a cleaning means 2.
5 and the toner collection box 26 are housed in the integrated process cartridge 15 to form a unit, and can be attached to and detached from the apparatus main body IO all at once. However, the process section unitized in the process cartridge 15 is not limited to this, and at least the photoreceptor belt controller 7 and the developing units 23a to 23d1 or the photoreceptor belt 17 and the cleaning means 25 can be integrated into a unit. Often, other process parts may be unitized together.

On the other hand, on the main body side of the image forming apparatus, when the process cartridge 15 is installed and an image can be formed, an exposure means, a transfer means, etc. are arranged around the photoreceptor belt 17. (See Figure 1) The exposure means includes a semiconductor laser writing optical system unit (hereinafter referred to as optical system unit) 2.
2, and the photoreceptor bell charged by the charger 21) 17
to form an electrostatic latent image.

The transfer means transfers the toner image formed on the photoreceptor bell 17 to a transfer material P by a transfer device 24 such as a transfer corona discharger.
Transfer on top.

The color image forming process by the color image forming apparatus having the above-described configuration is performed as follows.

First, the process cartridge 15 is connected to both image forming apparatus main bodies l.
It is loaded in the first position in O and is ready for image formation. When an image signal of the first color outputted from an image reading device separate from the apparatus main body 10 is input to the optical system unit 22, a semiconductor laser (not shown) in the optical system unit 22 emits a laser beam. A beam is generated. The laser beam is rotated and scanned by a polygon mirror 221 rotated by a driving motor (not shown), and an fθ lens 222 and a cylindrical lens 2
24 and three mirrors 223, the photoreceptor belt 1 is uniformly charged to a predetermined charge by the charger 21 in advance.
7 to form a bright line.

On the other hand, regarding the sub-scanning direction, a belt index (not shown) corresponding to a specific position of the photoreceptor belt 17 is detected, or a print command signal is received, and the process is performed based on this detection or command signal. , a main scanning line on which modulation of the semiconductor laser by the image signal is started is determined. When scanning is started, in the main scanning direction, the laser beam is detected by an index sensor (not shown), and based on this detected signal, modulation of the semiconductor laser by the image signal of the first color is started. The modulated laser beam is scanned over the surface of the photoreceptor belt 17. Therefore, a latent image corresponding to the first color is formed on the uniformly charged surface of the photoreceptor belt 17 by the main scanning by the laser beam l and the sub-scanning by the conveyance of the photoreceptor belt 17. This latent image is developed by a developing device 23 a containing yellow toner corresponding to the first color among the developing means, and a yellow toner image is formed on the surface of the photoreceptor belt 17 . Thereafter, the photoreceptor belt 17 passes under the cleaning grade 251 which is spaced apart from the surface of the photoreceptor belt 17 while holding the yellow toner image on its surface, and then passes through the second cleaning grade 251.
Enter color image formation.

That is, the photoreceptor belt 17 on which the yellow toner image has been formed is uniformly charged again by the charger 21, and then the image signal of the second color is inputted to the optical system unit 22, and the image signal of the above-mentioned first color is inputted to the optical system unit 22. As in the case of image signals, writing is performed on the surface of the photoreceptor belt 17 to form a latent image. The latent image is developed by a developer 23b containing magenta toner as the second color. A magenta toner image is formed in the presence of a previously formed yellow toner image.

Similarly, a cyan toner image is formed in the developing device 23c that accommodates cyan toner after forming a latent image based on the image signal of the third color, and further contains black toner after forming the latent image based on the image signal of the fourth color. The black toner image is superimposed on the surface of the photoreceptor belt 17 by the developing process Wr23d, and a color toner image is formed on the surface of the photoreceptor belt 17.

Developing sleeve 231a of each of these developing devices 23a to 23d
A DC or even AC bias is applied to ~231d, and non-contact development (
Jumping development) is now performed. Portrait,
For this non-contact development, either a -component developer or a two-component developer can be used. - When using a two-component developer, miniaturization can be achieved, but a development method using a two-component developer is superior in terms of development stability and is preferable in terms of color reproduction.

The color toner image formed on the surface of the photoreceptor belt I7 as described above is transferred from the paper feed cassette 16 to the paper feed roller 27.
The color toner image is supplied by a timing roller 28 and transferred onto a transfer material in synchronization with the color toner image. The transfer device 24 performs transfer by applying a high-voltage power output having a polarity opposite to that of the toner.

The transfer material P onto which the color toner image has been transferred in this manner is reliably separated by the photoreceptor belt 17 that changes direction rapidly (with a small diameter curvature) along the drive roller 18, and is transported upward by the transport belt 29.

Note that this conveyor belt 29 is equipped with a suction means 291 to reliably convey it upward while sucking it. After the toner is melted and fixed on the transfer material P by heating and pressure contact between the fixing roller 30A and the pressure roller 30B, the transfer material P is discharged onto the upper surface of the upper cover 11, which also serves as a paper discharge tray, by the paper discharge roller 31.

On the other hand, the photoreceptor belt 17 that has finished transferring the color toner image onto the transfer material P is further conveyed clockwise, and the cleaning means 25 brings the cleaning blade 251 into pressure contact.
The remaining toner is removed and cleaned. After cleaning is completed, the cleaning blade 251 separates from the photoreceptor belt 17 again and begins a new image forming process.

Next, a drive system for the process cartridge I5 and a drive system for moving the process cartridge will be described with reference to FIGS. 3 and 4.

FIG. 3 is a diagram showing the drive system for image formation, the drive system for moving the process cartridge, and the drive system for moving the cassette in the process cartridge 15 from the left side, and FIG. 4 shows the main parts of the process cartridge 15 and the drive system. FIG. The drive system for the process cartridge 15, the drive system for moving the process cartridge, and the drive system for moving the cassette shown in this embodiment are driven using two motors M1%M2.

First, the drive system for the photoreceptor belt 17 uses the driving force from the motor Ml. Gear G12 is arranged to mesh with gear Gll of the shaft of motor Ml. Further, when the process cartridge 15 is in a position where image formation is possible,
A drive gear G14 provided coaxially with the drive roller 18 that conveys the photoreceptor bell 1-17 meshes with a gear G13 that rotates together with the gear G12. That is, motor M
The rotation of the drive roller 18 is transmitted to the drive gear G14 via gear G11, gear GI2, and gear GI3 and controlled to an appropriate rotational speed. The photoreceptor belt 17 is rotated and conveyed.

A motor M2 is used as a drive system for the developing units 238 to 23d1, the waste toner screw 252, and the toner hopper 35. The rotational force of motor M2 is generated by gear G21 on the shaft of motor M2.
is transmitted to gear G22 via. Further, the signal is transmitted to a gear G23, which is coaxially and integrally provided with the gear G22, to drive the developing devices 23a to 23d, move the process cartridge 15, move the paper feed cassette 16, toner replenishment device R35, and waste toner. The recovery device 26 is driven, etc.

First, the drive system of the developing devices 23a to 23d will be explained.

The rotational force of motor M2 is transferred to gear G26 via gear G211, gear G22, gear G23, intermediate gear and spring clutch.
a, 26b, 26c, and 26d are driven and rotated.

These gears G26 (a=d) are developer drive gears G27a to G27d provided in the process cartridge 15.
mesh with. Developer drive gear G 27a - G 27d
The rotational force transmitted to the developing sleeves 231a to 231
d and the stirring screws 232a to 232d to drive the developing device.

The rotational force of the motor M2 transmitted to the pulley P22 is
The waste toner screw 252 is driven through a waste toner recovery drive system consisting of a clutch and a gear train.

The rotational force of the motor M2 transmitted to the pulley P22 is transmitted to the toner hopper 35a through a toner replenishment drive system consisting of a clutch, a gear train, a timing belt, etc.
The toner supply screw 352 and the toner stirring member 351 of ~35d are driven.

In this embodiment, the drive system of the photoreceptor belt I7 and the drive systems of the developing units 23a to 23d, the waste toner screw 252, the toner hopper 35 (a to d), the process cartridge moving means, and the cassette moving means are two types. Although the motors M1 and M2 are used for driving, these drives may be performed by one drive source motor or the like, and selectively switched by a switching means such as a clutch.

Alternatively, dedicated motors may be provided for the process cartridge moving means and the cassette moving means and driven separately from the drive source of the image forming means.

Next, the process cartridge moving means will be explained.

In FIG. 3, the rotational force of motor M2 transmitted to gear G22 is applied to pulley P2, which rotates together with gear G22.
1 and the timing belt TBI to the pulley P22, and also to the gear G29 meshing with the gear G2g which rotates integrally with the pulley P22. moreover,
The rotational force of motor M2 transmitted to gear G29 is further transmitted to gear G30 meshing with gear G29.

The rotational force is then transmitted to gear G31 via an electromagnetic clutch as necessary. Gear G31 and Gear G32
are intersecting bevel gears that transmit the rotational force transmitted to gear G31 to pinion gear PCI. This pinion gear PCI can mesh with a rack gear RGI provided on the side surface of the process cartridge 15,
The process cartridge 15 is moved in the left-right direction as shown in FIG. 1 by the rotation of the pinion gear PCI and the slide of the rack gear RG2.

The process cartridge 15 is provided with a rack gear RGI on its side surface, and also includes a drive gear G 14 for rotating the photoreceptor belt 17 and a developer drive gear G 27a.
-G 27d and waste toner screw drive gear G3
7 is provided.

On the other hand, in the process cartridge storage chamber of the apparatus main body 10, the drive gear G14 of the process cartridge 15, the gear G13 corresponding to the developer drive gear G27a to G27d, and the waste toner screw drive gear G34, and the gear G
26a-G 26d and gear G36 are provided. Further, a pinion gear PGI is provided so as to be able to mesh with a rack gear RGI provided on the process cartridge 15.

Further, in the upper part of the process cartridge storage chamber of the apparatus main body 10, first and second micro spindles MSI, M
S2 is provided. The first and second microswitches MSI and MS2 are connected to the process cartridge 15.
This is a detection means for detecting the position of. Here, the first
The second microswitches MSI and MS2 are connected to the drive gear GI4 provided in the process cartridge 15, the developer drive gear G27a to G27d, the waste toner screw drive gear G37, and the gear GI3 and gear provided in the apparatus main body IO. G26a - G26d, gear G3
6 engages with each other to enable image formation, and a position further away from the transfer device 24 compared to the first position, that is, a position retracted from the first position in the opposite direction to the insertion direction of the process cartridge 15. The second position is detected, and the position signal is output to the control unit.

Next, the movement process of the process cartridge 15 will be explained using FIG. 5 which schematically shows the movement of the process cartridge 15.

First, when removing the process cartridge 15, the fifth
As shown in Figure (A), the process cartridge 15 is in the first position where image formation is possible, and the drive roller 18 and transfer device 24 are kept at a desired distance (if the transfer member is a transfer drum, an appropriate pressure is applied). ), process cartridge! 5
A drive gear G14 and a developer drive gear G27 provided in the
a-G 27d, waste toner screw drive gear G3
7 and gear G13, gear G26a-G26d, and gear G for driving each provided in the device main body lO.
36, and is in a state where image formation can be performed optimally. Further, the rack gear RGI and pinion gear PCI are meshed with each other.

A signal indicating the presence or absence of the transfer material P from the jam detection sensor is used in a jam determination section to determine whether or not there is a jam. If it is determined that there is a jam, the jam determination section issues a jam signal to the control section. Then, the control section stops the drive sections related to image formation, such as the photoreceptor belt drive section, the developer drive section, and the fixing drive section, and controls the process cartridge moving means.

That is, the control unit issues a signal to the motor M2 and the electromagnetic clutch, which are the drive sources of the process cartridge moving means, and moves the process cartridge from the 15*1 position to the second position.
In order to move to the second position, the binion gear PCI is rotated, and the process cartridge 15 is moved along the guide member 37 in the direction of the second position (see FIG. 5(B)).
.

When the process cartridge 15 moves as shown in FIG. 5(C), the second microswitch MS2 detects that the process cartridge 15 has moved to the second position and sends a signal to the control unit. . When the control section receives the signal, it releases the electromagnetic clutch and stops the rotation of the motor M2. That is, the process cartridge 15 has a rack gear RGI and a pinion gear PGI.
It stops at the second position in the engaged state, and is retracted from the first position to the second position.

Next, the paper feed cassette moving means will be explained.

In FIG. 3, the rotational force of motor M2 transmitted to gear G29 is transmitted to gear G33 which meshes with gear G29. Then, the rotational force is transmitted to the pulley P22 via the electromagnetic clutch as necessary, and then to the pulley P24 via the timing belt TB2, and then to the pulley P24 via the timing belt TB2.
The signal is transmitted to gear G34, which rotates in unison with the signal. Gear G34 and gear G35 are cross-shaft gears (bevel gears), and the rotational force transmitted to gear G34 is transferred to pinion gear P.
Transmit to G2.

This pinion gear PG2 can mesh with a rack gear RG2 provided on the side surface of the paper feed cassette 16, and the rotation of the pinion gear PG2 and the slide of the rack gear RG2 move the paper feed cassette 16 in the left-right direction as shown in FIG. move it to

A signal indicating the presence or absence of the transfer material P from a jam detection sensor provided in the transfer material transport path from the paper feed cassette 16 through the paper feed section, transfer section, and fixing section to the paper discharge section is sent to a jam determination section to determine whether or not there is a jam. If it is determined that there is a jam, the jam determining section issues a jam signal to the control section. Then, the control section stops the drive sections related to image formation such as the photoconductor belt drive section, the developer drive section, and the fixing drive section, sends a movement signal to the number of process cartridge movement means and the cassette movement means, and also releases the upper cover. A release signal is issued to the means. The process cartridge moving unit controls the process cartridge moving drive system to move the process cartridge 15 from the first position to the second position, and is located at a position where it is detected that the process cartridge 15 has moved to the second position. When the detection signal is obtained, the process cartridge movement drive system is stopped.

Similarly, the paper feeding force cent moving means also moves the paper feeding cassette 1.
6 from the first position to the second position. On the other hand, the upper cover opening means opens the upper cover 12. In other words, when a jam occurs, the process cartridge 15 and paper cassette 16 are retracted to the second position without the operator having to do anything, and the upper cover 12 is opened, so that the jam can be removed from above the apparatus main body 10. The transfer material P causing the problem can be easily confirmed and removed. At this time, if the transfer material P is pinched between the fixing roller 30A and the pressure roller 3OB of the fixing device and a paper jam occurs, the pressure between both rollers can be automatically or manually released by fully opening the upper cover 12. If you do this, you can easily remove the transfer material. Furthermore, after clearing a jam, the process cartridge 15 and paper cassettes 1-16 are automatically inserted with a simple operation, which not only greatly reduces the operator's hassle but also allows them to be placed in the optimal position. Process cartridge 15 and paper cassette 16
can be set.

FIG. 6 is a perspective view showing essential parts of the process cartridge 15 and supporting member according to the present invention, and FIG. 7 is a sectional view of the image forming apparatus with the process cartridge 15 removed.

The shaft end portions of drive roller shafts 18A and 18B that rotatably support the drive roller 18 protrude from the inner side of both side plate portions of the housing of the process cartridge 15. Also,
The driven roller 19 is provided on the entrance side of both side plate portions of the casing.
A driven roller shaft 19A rotatably supports the.

The shaft end of 19B protrudes. Note that the driven roller shaft 1
The axial lengths of 9A and 19B are the same as those of the driven rollers 18A and 18B.
It is set longer than the shaft length of the

On the other hand, inside the apparatus main body 10, the process cartridge 1
58 and the housing chamber for the laser writing system unit (laser beam scanner) 22.
6B are arranged in parallel. The support member 36A.

On the left and right sides of each inlet side of 36B, there are parallel long groove portions 361A,
361B are bored, respectively, and form a reference plane in the height direction on which the left and right shaft ends of the driven roller shafts 19A and 19B slide and are guided and supported.

Process cartridge 1 of the support members 36A and 36B
5 Positioning members 37^, 37B are located on the left and right sides of the back side in the insertion direction.
are integrated. The positioning members 37A, 37
Long groove portions 37]A and 371B are bored in each of the grooves B, and the respective left and right shaft ends of the drive rollers 18A and 18B come into sliding contact with each other to guide and support them. In addition, the long groove portion 371^,
The end of the concave portion 371B forms a reference surface against which the drive roller shafts 18A, 18B abut and a reference surface in the height direction.

Further, long rail-shaped guide members 38A, 38B are integrally provided at the upper intermediate portions of the support members 36A, 36B. That is, one of the long groove portions 361A and 371
On the upper surface of the guide member 2.8A that connects the bottom of each long groove of A,
The shaft end of the drive roller shaft 18A is placed on it and slides thereon.

The driving roller 18B is mounted on the upper surface of the guide member 38B connecting the bottoms of the other long grooves 361B and 371B.
The shaft end is placed on it and slides. Note that the drive roller shaft 1
8A, 18B and the driven roller shafts 19A, 19B are fitted with rotatable rings or pole bearings, the long grooves 361^, 361B, 371^, 371
B, and the guide members 38^, 38B, the tff movement becomes smooth and can be operated easily.

The lower portions of the left and right support members 36A, 36B are connected by a bottom plate member 39 and are integrated. The laser writing optical system unit 22 is placed on the upper surface side of the bottom plate member 39. The bottom plate member 39 is provided with a positioning and holding member 391 for positioning and fixing the optical system unit 22. In this way, the support member 36A,
36B is the upper long groove portion 361A, 361B.

371A, 371B and guide members 38A, 38B,
Since the lower bottom plate member 39 and the positioning and holding member 391 are integrally constructed, their mounting positions are highly accurate and stable. Therefore, the accuracy of the stopped and held position of the process cartridge 15 in the first position is reliable, and the relative position with respect to the optical system unit 22 is accurate. Further, even when the process cartridge 15 is inserted and removed, and the optical system unit 22 is attached and removed, the reproducibility of each stop position is good, and the relative position accuracy does not change.

When installing the process cartridge 15 into the apparatus main body 10, with the front cover 14 open, the process cartridge 15 is held and directed toward the opening of the apparatus main body IO, and the drive roller shafts 18A and 18B are moved toward the guide member 3.
Place it along the top surfaces of 8A and 38B and slide it.

The drive roller shafts 18^, 18B are connected to the guide members 38A, 38
B is pushed in along the upper surface of the long groove portion 371A,
371B. Almost simultaneously, the driven roller shaft 19A
19B is also inserted into the long grooves 361A and 361B. This is the position shown in FIG. 5(C) described above.

If the process cartridge 15 is subsequently moved and pushed into the inside of the apparatus main body IO until it reaches the second position shown in FIG. do.

When this set signal is input, the control section controls the motor M2.
and sends a signal to the electromagnetic clutch, and the process cartridge 1
5 from the second position to the first position, the pinion gear PCI is rotated (rotated in the opposite direction to the direction of rotation when taking out the process cartridge 15), and the process cartridge 15 is moved from the long groove part 3 to the first position.
Along 61A, 361B, 371^, 371B, the first
The paper feed cassette 16 is moved in the direction of the position (FIG. 5(B)).

When the process cartridge 15 is further moved by the driving force, the switch MSI is turned on as shown in FIG. 5(A), and the process cartridge 15 is moved to the first position.
It detects that it has moved to the position and sends a signal to the control unit. When the control section receives the signal, it releases the electromagnetic clutch and stops the rotation of the motor M2. Although the process cartridge 15 moves slightly due to inertia, the drive roller shafts 18A and 18B are connected to the long groove portions 37JA and 371B.
It comes into contact with the recess at the end of each groove, stops at a predetermined first position, and is locked by a known locking mechanism.

When the process cartridge 15 reaches the stop position at the first position, the gear G1 on the process cartridge 15 side
4 and gear G13 on the device main body lO side are in mesh,
Rotation of the photoreceptor belt 17 becomes possible.

FIG. 8 is a sectional view of a color image recording apparatus in which an image reading device (scanner) 60 is mounted on the upper part of the image forming apparatus main body 10. Even in the case where the process cartridge 15 can be inserted into and removed from the apparatus main body 10 having an integral structure in which the upper part of the apparatus main body IO is closed, the process cartridge 15 and the optical system unit 22 are attached to the support member.
It is easy to attach and detach, and high positioning accuracy can be set.

In this embodiment, an image forming method was described in which a color toner image is formed on the photoreceptor belt 17 and then transferred to a transfer material in -th cycle as an image forming process. A color imaging method may also be used in which toner images are transferred onto a transfer paper P in layers. Further, it is also applicable to a normal monochrome printer using a monochrome process.

Furthermore, although the non-contact development method has been described as a developing method, the present invention is not limited to this non-contact development, but can also be applied to contact development.

Further, the drive system shown in this embodiment is merely an example, and it goes without saying that the drive system is not limited to combinations of these gears, clutches, belts, etc.

These various process cartridges are not limited to the horizontal arrangement shown in the drawings, but may also be movable in an inclined arrangement.

Note that a process cartridge using a photosensitive drum as an image carrier may be constructed and the process cartridge may be made movable.

〔Effect of the invention〕

As described in detail above, the image forming apparatus of the present invention has high relative positioning accuracy and stable maintenance when the process cartridge, which can be inserted into and removed from the apparatus main body, and the laser writing optical system unit, which is removable, are installed. can do.

In addition, positioning reproducibility is good and maintenance is easy. This has made it possible to provide an image forming apparatus that can obtain high-quality images.

[Brief explanation of drawings]

Fig. 1 is a side sectional view showing the main cross section of a color printer to which the image forming apparatus of the present invention is applied from the left side, Fig. 2 is a sectional view of the process cartridge, and Fig. 3 is a sectional view of the drive system of the image forming apparatus from the left side. 4 is a cross-sectional view showing the main parts of the process cartridge and the drive system, FIG. 5 is a schematic diagram showing the movement process of the process cartridge, and FIG. 6 is the main part of the process cartridge and support member according to the present invention. FIG. 7 is a sectional view of the image forming apparatus with the process cartridge removed, and FIG. 8 is a sectional view showing another embodiment of the image forming apparatus according to the present invention. IO...Device main body 14...Front cover 15.
・Process cartridge 16 ・Paper feed cassette 17 ・Photoreceptor belt I8 ・
- Drive rollers 18^, 18B... Drive roller shafts 19A, 19B... Driven roller shafts 21... Charger 22... Laser writing optical system unit 23... Developer device 24... Transfer device 25 ...Cleaning means 36A, 36B...Supporting member 36]^, 361B.
...Long groove portions 37A, 37B...Positioning member 38
A, 3313... Guide member 39... Bottom plate member 39
1... Positioning and holding member 50... Transfer drum 6o... Image reading device M1, M2... Motor (drive source) P... Transfer material (transfer paper)

Claims (2)

[Claims] (1) A process cartridge in which an image forming means including an image carrier on which an electrostatic latent image is formed is integrated into a unit and can be inserted into and removed from the main body of the apparatus; In an image forming apparatus including a laser writing optical system unit that converts supplied image information into an optical signal to form a latent image, an apparatus main body that supports the laser writing optical system unit and positions and fixes it at a predetermined position. An image forming apparatus characterized in that the supporting member is provided with a positioning portion for supporting and fixing the process cartridge at a proper loading position where image formation is possible. (2) The image forming apparatus according to claim 1, wherein the support member is provided with a guide portion that supports the process cartridge and allows it to be freely inserted and removed.