JP2825857B2 - Electrostatic recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electrostatic recording device such as a copying machine.

2. Description of the Related Art In general, in an electrostatic recording apparatus, after a photosensitive member surface is uniformly charged by a charging charger, a visible image is formed through an exposure and development process, and this is transferred to transfer paper by a transfer charger, and further fixed. I go through the process.

Here, ozone O ₃ generated by the discharge of the charging charger and the transfer charger adversely affects the electrostatic latent image on the photoconductor. That is, if the ozone O ₃ adheres to the surface of the photoreceptor, the uniform charging property by the charging charger or the like is impaired, and the charged charge is not uniformly deposited, which causes image blur.

For this reason, in consideration of the airflow in the internal space of the machine, such ozone O ₃ is discharged to the outside of the machine via a filter by a blower fan. In some cases, such a blowing fan is provided in a charging case to forcibly remove ozone O ₃ .

SUMMARY OF THE INVENTION However, poor removal efficiency of ozone O ₃ is in this manner, is insufficient to prevent the adverse effects of ozone O _3. In addition, the cost is high if a dedicated fan is provided.

Means for Solving the Problems After uniformly charging the surface of the endless belt-shaped photoreceptor by the charging means, an electrostatic latent image is formed on the photoreceptor and visualized by the developing means. In an electrostatic recording apparatus in which an image is transferred onto transfer paper by a transfer unit and the transferred image is fixed by a fixing unit having a fixing roller with a built-in heat source, a cooling fan for cooling the inside of the apparatus is attached. A heat insulating cover that covers an upper space of the fixing roller, and an opening extending in the vicinity of a transfer position by the transfer means, and a first duct for air intake that covers the entire heat insulating cover including the cooling fan. A second duct for intake having an opening extending in the vicinity of a charging position provided by the charging means and communicating with the cooling fan, and communicating with an exhaust side of the cooling fan to generate an exhaust flow. outside A third duct for guiding was provided.

The ozone generated around the photoreceptor due to the discharge by the charging means and the transfer means is discharged together with the first duct and the second duct whose opening positions are extended in the vicinity of the positions of these members.
Using the duct as a guide, the air is forcibly and efficiently exhausted by the intake / exhaust flow of the cooling fan, and the adverse effect of ozone is reduced. At this time, a cooling fan is used to prevent an increase in the temperature inside the apparatus due to a fixing roller having a built-in heat source, and a dedicated fan is not required for exhausting ozone.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

First, the overall structure and operation of a copying machine to which the present invention is applied will be described with reference to FIGS. FIG. 2 is a perspective view showing the entire external appearance when not in use, FIG. 3 is a perspective view showing the external appearance in a copy processing standby state, and FIG. 4 is a sectional structural view schematically showing the process configuration. As shown in FIG. 2 and the like, the copying machine of the present embodiment is configured as a vertical / thin copying machine mainly used by leaning along a wall.

As shown in FIG. 2, the copying machine of the present embodiment includes a document transport table 1 which also serves as an exterior cover,
Front cover 2, paper feed table 3, left and right side covers 4,
5 and a back cover 6. A louver 7 is provided on each of the left and right side covers 4 and 5.

In order to shift from such an unused state to a copy processing standby state, first, the handle 8 provided at the upper part on the outer surface side of the document conveying table 1 is opened and rotated to the front side as shown in FIG. Open to the specified position. In this open state, the pair of side guides 9 on the inner surface side of the document transport table 1 are exposed, and serve as guides for inserting a set of documents. The pair of side guides 9 move closer to and away from each other in conjunction with each other, and can be adjusted to the width of the document. A size mark 10 indicating a document size and a center position is provided on the innermost side of the document transport table 1.
Is provided as a guide for the insertion set of the manuscript. Further, as the document conveying table 1 is opened and rotated, the sheet discharging rollers 11 located on the inner surface and the document discharging table 12 also serving as a document conveying cover are exposed as shown in FIG.

When the outer surface of the paper feed table 3 is pressed, the lock means (to be described later) is released, and the paper feed table 3 is linearly opened and rotated by a damper means (to be described later) provided at a fulcrum, and is moved to a predetermined position as shown in FIG. Is fixed open. The paper feed table 3 is for stacking and setting transfer papers to be copied on the front surface thereof. Similar to the document transport table 1, the paper feed table 3 moves close to and away from one another in conjunction with the paper size, and guides a pair of paper leading edge curls. A side guide 13 is provided. A size mark 14 indicating a paper size and a center position is attached to a position on the front side of the paper feed table 3 and serves as a guide for inserting the transfer paper. In the center of the innermost portion of the sheet feeding table 3, a friction pad that comes into contact with the call roller 15 is provided.
16 are provided. When the paper feed table 3 is opened,
An inner cover provided on the inner surface to cover the fixing section, etc.
17 is exposed.

When the document transport table 1 and the paper feed table 3 are opened in this way, the main power supply of the apparatus is activated and enters a standby state in about 20 seconds. The operation from the start to the end of copying will be described with reference to FIG.

As shown in FIG. 4, a photoconductor 20 in the form of an endless belt is provided as a basis of an electrostatic recording type copying machine. According to, the charger 21, the exposure optical system 22, the developing device 23,
Each process unit of the transfer charger 24, the fixing device 25, the cleaning device 26, and the charge removing LED array 27 is provided in order. A document feeding and conveying means 28 is provided above the exposure position by the exposure optical system 22, and the transfer charger 24 is provided.
A transfer paper feeding / conveying means 29 is provided below the transfer position. In the present embodiment, the photoconductor 20 is provided at a substantially central position in the case in a vertically elongated state in which the interval between the central portions in the belt is narrow, and each of the process units described above is disposed above the periphery of the photoconductor 20. It is arranged in a narrow state in order from below. A cooling fan 30 is also provided below the cleaning device 26.

First, when the original transport table 1 is opened and rotated, the opening is detected by the original transport table open / close switch 31. When the paper feed table 3 is pressed, the lock means is released, and when the paper feed table 3 is opened semi-automatically by the damper means, the release is made by a paper feed table opening / closing switch.
Detected by 32. AND of these open / close switches 31, 32
, The warm-up of the unit is started. Here, the fixing heater 33 as a heat source, the fluorescent lamp heater
34 and the cooling fan 30 complete the warm-up after about 20 seconds. In such a state, the transfer paper of the same size as the original or the size to be copied is abutted on the leading guide 35 on the paper feed table 3 using the side guide 13 as a guide. Then, the paper presence / absence sensor 36 provided on the paper feed table 3 is turned on, and a display (not shown) indicates that paper is set. As a result, the copying machine becomes ready to copy, and waits for the insertion setting of the document.

The document is inserted and set on the document transport table 1 with the document face down with the side guide 9 and the size mark 10 as guides, and abuts against a pair of document transport rollers 37 and 38. Such a document insertion set is detected by a document presence / absence sensor 39 provided in front of the entrance roller 37. After this detection, the conveyance rollers 37 and 38 are driven after a certain pulse time, and the conveyance of the document is started. That is, the output of the document presence sensor 39 regulates the drive start time of the transport rollers 37 and 38, and the waiting time causes the leading edge of the document to follow the registration roller. That is, the skew correction time is secured. However, the leading edge of the document is limited to the one perpendicular to the transport direction.

The original conveyed by the conveying rollers 37 and 38 further includes:
The document is conveyed to the back over the contact glass 41 while being pressed by the internal document pressing plate 40. During this transport, the leading edge of the original is located below the contact glass 41.
Detected by 42. In order for the sensor 42 to detect the leading edge of the document, a round hole or notch is formed at a position of the document pressing plate 40 facing the sensor 42.

The exposure optical system 22 is provided downstream of the sensor 42. The exposure optical system 22 includes a fluorescent lamp 43 for exposing the original surface of the original conveyed on the contact glass 41 and a reflecting plate 44 for efficiently reflecting a part of the light of the fluorescent lamp 43 to the original surface.
And a rinse (imaging optical element) 45 for condensing and irradiating the light reflected from the document surface onto the photosensitive member 20.

On the other hand, the document inserted and transported by the transport exposure rollers 37 and 38 is transported by a pair of transport rollers 46 and 47 provided on the back side of the contact glass 41, and is transported by an inner guide 48 and an outer guide 49. The formed reverse conveyance path 50
Is discharged onto the document discharge table 12 by the discharge rollers 11. The outer guide 49 is formed by a part of the back cover 6 and also serves as an outer cover. These rollers 11,3
7, 38, 46, 47, reversing conveyance path 50 and tables 1, 12 etc.
The document feeding / conveying means 28 is configured.

In synchronization with the drive of the photoconductor 20 being started in conjunction with the drive motor by the document detection by the document presence sensor 39,
Transfer charger 24, static elimination LED array 27 and the fluorescent lamp 43
Is turned on. When the position of the photoconductor 20 corresponding to the position where the leading end of the document reaches the optical axis of the rinse 45 reaches the timing before the drive reaches the position of the charging charger 21, the charging charger 21 is turned on, and the surface of the photoconductor 20 is cleaned. Uniform charging, that is, a uniform potential is applied.

Then, the reflected light from the original is rinsed by the
An image is formed thereon to form an electrostatic latent image. The electrostatic latent image is developed by the developing device 23, and the visualized toner image is transferred onto transfer paper at the position of the transfer charger 24.
After the transfer, the toner remaining on the photoconductor 20 is scraped off by the blade 51 of the cleaning device 26. Further, the residual potential on the surface of the photoconductor 20 is removed by irradiating the charge eliminating LED array 27 with light.

Here, the photoreceptor 20 has a seam, and a reflection mark 52 and a developing device 23 provided at an end of the surface of the photoreceptor 20 as shown in FIG. 5 so that an image is not formed over the seam position. The home position of the photoconductor 20 is detected by a seam sensor 53 provided at a lower portion, and the belt is driven, that is, the drive motor is turned off.

On the other hand, the drive is transmitted to the clutch on the paper feed table side in conjunction with the drive motor by the detection signal of the document presence sensor 39, the paper feed solenoid is turned on by the detection signal of the document leading edge detection sensor 42, and the clutch shaft is The transfer paper stacked on the paper feed table 3 is fed and conveyed by the paper feed roller 55 and the call roller 15 that are engaged. At this time, the paper feed roller 55
The uppermost one of the stacked transfer sheets is separated and conveyed by the friction pad 56 pressed against the sheet. Also, call roller 15
The tip guide 35 is also displaced downward to the lower retreat position at a timing linked to the descending sheet feeding operation.

The transfer paper transported by the paper feed roller 55
The sheet passes through a reversing conveyance path 59 composed of the outer guide 58 and the outer guide 58, and moves toward the transfer position of the photoconductor 20 in a reversed state. Here, a registration roller 60 and a driven roller 61 are provided before the transfer position, and the transfer paper is temporarily stopped at these rollers 60 and 61, and the timing is adjusted so that the transfer paper coincides with the leading edge of the image on the photoconductor 20. Controlled. That is, the clutch engaged with the shaft of the registration roller 60 is interlocked with the drive motor similarly to the drive transmission of the above-described paper feed clutch, and is driven and transmitted to the registration roller 60 by the detection signal of the document leading edge detection sensor 42, Synchronization with the visual image is achieved. Further, a detection signal of the seam sensor 53 can be used as the registration start signal.
Further, a paper presence / absence detection sensor 62 for performing jam detection is provided at a position immediately before the registration roller 60.

The transfer paper conveyed at a predetermined timing by the registration roller 60 receives the transfer of the toner image on the photoconductor 20 by the transfer charger 24. Thereafter, the transfer paper is conveyed while being thermally fixed by the pair of the fixing roller 63 and the pressure roller 64 of the fixing device 25, guided by the peeling claw 65, and discharged out of the apparatus by the discharge roller 66. That is, the transfer sheet feeding and conveying means of the present embodiment
The transfer paper transport path in 29 includes a paper feed path of paper feeding means by a paper feed table 3, a call roller 15, a paper feed roller 55, and a friction pad 56, a reverse transport path 59, a pair of registration rollers 60 and driven rollers 61, and , The transfer path by the transfer charger 24, the pair of the fixing roller 63 and the pressure roller 64,
And the operation side (front side) is set to the sheet insertion and sheet discharge side, as in the case of the document feeding and conveying means 28.

That is, the reversing conveyance paths 49 and 59 are for reversing and conveying the sheet in the clockwise direction in FIG. 4. The transfer direction of the original and the transfer sheet is made coincident with the photosensitive member movement direction at each operation position by performing the exposure and performing the transfer after the reversal on the transfer sheet feeding / conveying device 29 side. Therefore, all operations on the original and the transfer paper can be performed only on the operation side of the apparatus, and the operability is improved.

At this time, a paper ejection detection sensor 67 provided near the paper ejection roller 66
The jam detection from the sensor 63 in the registration unit is performed by using the detection signal of the registration unit, a signal is supplied to the joint sensor 53 by the OFF signal (at the time of passing the rear end), the reflection mark 52 on the photoconductor 20 is detected, and the driving motor Off. The transfer charger 24, the static elimination LED array 27, and the fluorescent lamp 43 are synchronized with the drive motor being turned off.
Is turned off.

Further, the charging charger 21 is turned off at the corresponding position of the photoconductor 20 when the position where the document presence detection sensor 39 is turned off reaches the optical axis of the rinse 45. The paper feed solenoid is turned off in synchronization with turning on of the registration solenoid, and the registration solenoid is turned off in synchronization with turning off of the sheet ejection detection sensor 67.

As a result, the copy processing operation is completed, and the apparatus enters a standby state. Then, by closing the original transport table 1 and the paper feed table 3 in the state shown in FIG. 2, the respective open / close switches 31, 32 are turned off, and in synchronization with this, the fixing heater 3 is turned off.
3. The fluorescent lamp heater 34 and the cooling fan 30 are turned off.

Hereinafter, the configuration, operation, and the like of each process unit and the like constituting the present apparatus having the above-described general operation will be individually described in detail.

[Photoconductor 20] See FIGS. 5 to 8.

The endless belt-shaped photoreceptor 20 has a plurality of rollers positioned on its inner peripheral side, that is, a driving roller 70 and a cleaning roller.
The developing roller 73 and the tension roller 74 are supported in a vertically long state having an inverted triangular shape by the transfer roller 72 and the transfer roller 72, and the gap between the center portions in the belt is reduced by abutting the developing roller 73 and the tension roller 74 into the concave shape. It is in a narrow state. When the drive motor 75 (see FIG. 7) is turned on, the drive gear 76 engaged with the drive roller 70 is interlocked, and drives the photosensitive member 20 to rotate at a constant speed with the document conveyance roller 37. Here, the drive roller 70 is made of a material having a large frictional resistance such as a rubber roller or a flocking roller, and is provided downstream of the image forming position of the rinse 45 with respect to the photoconductor 20, but provided at an upstream position of the developing roller 73. I have. By providing the drive roller 70 at such a position, the photoconductor 20 is always provided with a tension for imparting flatness to the image forming position, and the developing roller 73 side is a loose side, so that the developing roller 73 and the photoconductor 20 The stress at the nip portion is relieved, and the following properties are obtained.

The transfer roller 72 is disposed at a position downstream of the developing roller 73 and facing the transfer charger 24. Drive rollers located at approximately the same position on the same vertical line
70, the developing roller 73 and the transfer roller 72
The device is thinner because it is concave and the developing nip of the developing roller 73 is widely secured, and the inner developing roller 73 is cut into the empty space on the inner peripheral side of the photoconductor 20 as much as possible. Is done.

The cleaning roller 71 is disposed at the same height position as the drive roller 70, that is, at a position where the image forming portion of the photoconductor 20 is opposed to the drive roller 70 so as to be orthogonal to the image forming optical axis by the rinse 45. I have. The blade 51 faces the cleaning roller 71. The tension roller 74 is arranged so as to be depressed in a state where the photoconductor 20 is depressed at an intermediate outer peripheral position between the cleaning roller 71 and the transfer roller 72. In this way, the photoreceptor 20 is provided in a vertically elongated state, and is provided in a narrow state in which the central portion is as concave as possible.

Here, the position of the tension roller 74 is downstream of the transfer position and upstream of the charging position, and does not affect the latent image and the visible image on the photoconductor 20. It may be. The tension roller 74 is preferably a soft touch roller such as a brush roller or a surface flocking roller for preventing the surface of the photoconductor 20 from deteriorating, and is preferably driven at a constant speed with the photoconductor 20. As the flocked material, an acrylic polymer-based carbon array organic conductive fiber is preferable.

The transfer roller 72 has a smooth surface and low friction. Therefore, in order to prevent the photoconductor 20 from shifting, the anti-shift guide ridges 77 are formed on both sides of the inner periphery of the photoconductor 20 (see FIG. 5 and the like), and are regulated by the end of the transfer roller 72. (See FIG. 35). The guide ridge 77 is mainly made of a urethane rubber material, and does not hinder the flexibility of the loop of the photoreceptor 20 and prevents the environment from deteriorating. The transfer roller 72 is a photoconductor
In order to prevent the temperature inside the loop 20 from rising, a porous hollow roller having no problem in the surface properties of the photoconductor 20 is suitable.

Note that a means for imparting flatness such as a tension plate may be provided on the inner surface of the imaging position of the photoconductor 20 to prevent image blur. However, according to the present embodiment, the above configuration minimizes the span between the driving roller 70 and the cleaning roller 71, and the image forming position is located on the pulling side of the driving roller 70. The image blur can be prevented without providing a suitable tension plate or the like.

By the way, on both sides of the image effective area on the surface of the photoreceptor 20 formed into a loop shape by the seam, as shown in FIG. 5, conductive layers 78 made of black paint are provided. The casing 79 of the photoreceptor 20 has a neutralizing brush 80 that is in contact with the conductive layer 78.
Are provided near the drive roller 70. Static elimination brush
A leaf spring 81 is in contact with 80, and the conductive layer 78 is grounded via the neutralizing brush 80 and the leaf spring 81. The detection mark 52 for seam detection is made of gold and is provided on a part of the conductive layer 78. An opening 82 is formed in the casing 79 at a position on the orbit of the detection mark 52 so as to face the seam sensor 53, and the detection mark is formed by the seam sensor 53.
52 is detected, and is used for control for always setting the seam position to a non-image area. Also, on a part of the surface of the photoconductor 20,
A non-charged layer portion 83 for forming a blank portion at the leading end of the transfer sheet is formed over the entire width at a position corresponding to 3 ± 2.5 mm with respect to the leading end of the sheet. The non-charging layer 83 is formed by painting a black conductive material, and its position is controlled by a detection signal of the joint sensor 53.

Generally, in this type of electrostatic recording apparatus, after the image on the photoconductor 20 is transferred to transfer paper and separated from the photoconductor 20, a post-process such as fixing is performed. ,
It is necessary to prevent fixing jam due to winding of the transfer paper around the fixing roller 63. Here, after uniformly charging the surface of the photoconductor 20, an image is obtained on the transfer paper through each of the processes of exposure, development, transfer, and fixing. It is not charged even if it receives various charges,
Since no electrostatic latent image is formed, this is equivalent to erasing the charge by the eraser. Accordingly, by adjusting the timing of the position of the non-charged layer portion 83 and the timing of the leading edge of the transfer paper, a white spot can be formed at the leading edge of the transfer paper without using an eraser. Therefore, the device can be made compact. Further, as described above, it is easy to provide such a non-charged layer portion 83 in a belt-shaped photoconductor by coating or the like.

A casing 79 that supports and covers the mechanism around the photoconductor 20 rotatably supports each of the rollers 70 to 72 via a slide bearing, and has a casing 79 that is free from the bending habit due to the loop configuration of the photoconductor 20. In consideration of a case where contact with the inner surface may occur, a low-friction member is provided at an inner surface treatment (low-friction treatment) for preventing the photoreceptor 20 from deteriorating or a key point in the casing 79.

The casing 79 has a lower guide (not shown) provided on the main body side plates 85 on both sides and a bearing of the transfer roller 72 fitted therein.
Similarly, by rotating the bearing 89 (see FIG. 8) of the cleaning roller 71 with the upper guide 88 which engages with the main body side plate 85, positioning with the exposure optical system described later is performed.

[Document feeding and conveying means 28]: see FIGS. 9 and 10.

The document feeding / conveying means 28 is arranged at the uppermost position above the photoconductor 20. First, when the original conveying table 1 whose outer surface also serves as an outer cover is manually pushed, the lock 90 provided inside is released. When the grip 8 is gripped and lifted, the relay fulcrum 91, the rotation fulcrum 92, and the arm 93 are lifted. And the document conveying table 1 is guided to the set open position.

As shown in FIG. 10, a pair of side guides 9 provided on the document conveying table 1 are respectively connected to rack gears 94 and 95 disposed inside and a pair of rack gears 94 and 95 located at the center. With the pinion gear 96 meshing with 95,
When one side guide 9 is moved, the other side guide 9 is also moved in the opposite direction by the same amount.

Inside, transport rollers 37 and 46 rotatably supported by a main body side plate 85 via bearings are provided at front and rear positions of the contact glass 41. These transport rollers 37, 46
The driven rollers 38 and 47 which are driven and rotated are provided on the upper part of the roller. Document holding plate 40 located on contact glass 41
Is rotatably supported by the bearing of the driven roller 47 and is provided so as to be positioned on the contact glass 41 by its own weight. The lower surface of the document pressing surface 40 is white and is made of a low friction material.

The outer guide 49 is formed as a guide fin by a rib of the rear cover 6 of the main body. Further, an inner guide 48 is provided which guides the document conveyed by the pair of rollers 46 and 47 at a certain interval with respect to the outer guide 49 to the sheet discharging side. The original conveyed by the guides 48 and 49 through the reversing conveyance path 50 is fed to the paper discharge rollers 11 attached to the document feed / conveying means 28 and the paper discharge rollers attached to the rear cover 6 of the main body. It is discharged by a plurality of driven rollers 97 that are in pressure contact with 11.

As described above, the document transport / eject path is simplified and shortened.When copying the largest copy document, a trouble occurs during the transport of the transfer paper after the registration position, jam detection occurs, and the drive motor 75 operates. Even if the document is stopped, the document is completely discharged, so that maintenance of the document at the time of the transfer paper jam becomes unnecessary. If a paper jam occurs during the feeding of the transfer sheet before the registration position of the transfer sheet, the document is in the middle of being transported, and therefore exists in the document feeding and transporting means 28. The document discharge table 12 is pivoted open around a hinge 98,
Further, the original holding plate 40 is also held by the driven roller 47
By lifting around the axis, the contact glass 41 or the outer guide 49 is openly exposed, so that the original can be removed. Further, cleaning on the contact glass 41 is also possible.

[Exposure optical system 22]: see FIGS. 11 to 13.

The exposure optical system 22 is disposed immediately above the photoconductor 20 and below the document feeding and conveying means 28. In the exposure optical system 22, each component is laid out on one floor by an optical unit base 100 attached to the main body side plate 85. First, a socket 101 that holds both ends of a fluorescent lamp 43 that illuminates when a document conveyed by the document conveying roller 37 passes over a contact glass 41 having a thickness of 3 mm is positioned on a rising piece of the optical unit base 100. Installed. Since the image density changes depending on the tube wall temperature of the fluorescent lamp 43, a stable time is required until the set light amount is reached. Since this changes depending on the environment and manual notch operation, in this embodiment, the fluorescent lamp heater 34
The fluorescent lamp 43 is synchronized with the start of warm-up of the main unit.
Warm up the tube wall. The fluorescent lamp heater 34 is also supported on the optical unit base 100, and is pressed against the fluorescent lamp 43 by a spring 102. In consideration of such a tube wall temperature of the fluorescent lamp 43, according to the present embodiment, the unit unit is made into one floor by the optical unit base 100, and cooling by the heat radiation of the fluorescent lamp 43 is prevented. Accordingly, the warm-up time is shortened, and the fluctuation due to the external environment is also reduced.

The aperture angle of the fluorescent lamp 43 is set in the range of about 60 to 80 °, which is the most efficient with respect to the amount of light. A light and low-cost aluminum brilliant alloy plate is used for the reflection plate 44 for condensing the reflected light from the document surface, and the side erase-shaped portion 44a for reflecting to a position outside the maximum copying width of the photoconductor 20 is also included. It is bent integrally. By performing side erase outside the image area on both sides by the side erase shape portion 44a, the burden of preventing toner scattering near both sides of the cleaning device 26 is reduced.

On the back side of the reflector 44, an opening 44 formed in the reflector 44 is provided.
The automatic light control sensor 103 is mounted on the optical unit base 100 so as to face b. This automatic light control sensor 103
Detects the amount of light of the fluorescent lamp 43, converts the voltage, converts the voltage, compares the voltage with a reference voltage previously specified by a manual notch, and outputs a dimming control signal corresponding to the comparison result to the fluorescent lamp ballast. The fluorescent lamp ballast converts the dimming control signal into a lighting signal to vary the light emission output of the fluorescent lamp 43, and by repeating this, the light amount of the fluorescent lamp 43 is controlled so as to be stabilized at the notch designated in advance. You. The emission color of the fluorescent lamp 43 is green,
The peak wavelength is set to 543 nm, which is the wavelength most suitable for the spectral sensitivity of the photoconductor layer of the photoconductor 20.

Note that the original leading edge detection sensor 42 is
It is housed in the same case as 3.

The optical unit base 100 is provided with brackets 104 for supporting and positioning the contact glass 41 and for supporting both sides of the rinse glass 45 as positioning holders. A leaf spring (not shown) for fixing the rinse 45 near the bracket 104 is also provided. Around the rinse 45, a soft foamed polyurethane 105 for shielding the reflected light is provided, and while preventing the flare light to the exposure slit 106 side formed in the optical unit base 100 in opposition to the rinse 45, the main body side Also, it is designed to prevent the resonance from occurring.

[Charging charger 21 and static elimination LED array 27] ... see FIG. 6 and FIGS. 14 to 19.

The charging charger 21 is disposed above the photoconductor 20 and upstream of the rinse 45. More specifically, it is located on the lower surface of the optical unit base 100 and is located upstream of the exposure slit 106 with respect to the moving direction of the photoconductor 20.
Charger 21 is made up of casing 110 and charger wire 1
11 and a grid 112 (see FIG. 19). The casing 110 is formed by cutting and bending the optical unit base 100.
The casing arm 114 is fixed to the optical unit base 100 on the side opposite to the casing claw 114 by fitting the casing claw 114 facing the cut and bent portion 113 using the guide 113 as a guide. The optical unit base 100 is provided with a leaf spring 116, and the casing 110
Is pressed to perform positioning. Openings 117 are formed at three places in the upper surface of the casing 110 in the longitudinal direction, and ozone O ₃ due to discharge that adversely affects the formation of an electrostatic latent image is discharged from the casing 110.
It is designed to escape from inside to outside.

As shown in FIG. 6, a grid 112 for giving a uniform charging potential to the photoreceptor 20 applies tension to a bracket 118 engaged with a casing 79 via a spring 119,
A constant gap with respect to the photoconductor 20 is always maintained. A varistor 120 is provided on the optical unit base 110 to perform a constant discharge without being affected by discharge unevenness of the charger 21, environmental fluctuation, power supply fluctuation, and the like. The connection with this varistor 120
This is carried out by a leaf spring 122 provided through. This prevents non-uniform charging due to external factors. The ground leaf spring 81 of the neutralizing brush 80 is also supported by the optical unit base 100.

The charge removing LED array 27 is disposed at a position upstream of the charging charger 21 and removes a residual potential remaining on the surface of the photoconductor 20 after the transfer process. The static elimination LED array 27 is positioned and supported by a holder 123 attached to the optical unit base 100. The charge removing LED array 27 is irradiated with a light intensity of 23 to 46 μW / cm ² over a wider area than the charging width of the charging charger 21.

[Developing device 23]: see FIGS. 20 to 24.

After uniform charging, the electrostatic latent image formed on the photoreceptor 20 by the exposure optical system 22 is substantially inverted at the position of the driving roller 70,
Developing is performed by the developing device 23 provided on the rear cover base 130 in the innermost rear cover 6 located on the lower side of the rear cover 6 opposite to the operation side. Here, since the developing device 23 contacts the developing roller 73 with the photoconductor 20 in a state where the belt-shaped photoconductor 20 is concavely concave, it is necessary to secure a sufficient development nip and perform a stable developing operation. Can be.
In addition, the useless space in the belt is reduced as much as possible, and the developing device 23 can be disposed around the concave shape formed by the developing roller 23, so that further reduction in thickness and size can be achieved. In addition, by disposing only the developing device 23 behind the photoconductor 20, the developer is less contaminated on the operation side that requires opening and the like.

The developing device 23 employs a one-component magnetic roll developing system, and replenishes consumed toner with a toner cartridge 131. The toner cartridge 131 is inserted into guide grooves 133 formed in the developing unit side plates 132 on both sides.
The rotation shaft 134 of the toner cartridge 131 is fitted and positioned, and the pins 135 at both ends are fitted and positioned in the positioning grooves 136 of the developing unit side plate 132 while rotating the toner cartridge 131.

The toner is supplied from the toner cartridge 131 by engaging the attached winch 137 with the shield, chucking the roller 138 rotatably supported by the toner cartridge 131, and rotating the roller manually. As a result, the shield is wound and peeled off by the roller 138, the lower surface of the toner cartridge 131 is fully opened, and the toner inside falls.

The dropped toner is supplied to the developing unit side plate 132 and the casing 1
The developer is deposited in the developing housing including the blade 39 and the blade holder 140. The scattering of toner, which is a problem during the falling-down transfer process, can be prevented by sealing the casing 139, the blade holder 140, and the casing installation portion of the developing unit side plate 132 with the soft foamed polyurethane 141 interposed therebetween.

The toner accumulated in the developing housing is agitated by the agitator 142 rotatably supported on the developing unit side plate 132 via a shield bearing, thereby preventing blocking due to accumulated toner. Below the agitator 142 and at the lowest position in the housing, two blade rollers 143 and 144 rotatably supported on the developing unit side plate 132 via a shield bearing in the same manner as the agitator 142 via the developing roller 73.
Are provided side by side. Here, since the bottom of the casing 139 is formed in a curved shape along the rotation locus of these two blade rollers 143, 144, the rotating two blade rollers 143, 144 form a narrow portion with the casing 139. As a result, the toner dropped on these two blade rollers 143 and 144 is transferred in the rotation direction. As a result, the toner is transferred from the agitator 142 to the two-blade roller 144 via the two-blade roller 143, and is smoothly supplied to the developing roller 73 by the two-blade roller 144.

The developing roller 73 has a built-in magnet for conveying toner. Further, a metal blade plate 145 for frictionally charging the toner is attached to the blade holder 140, and the lower side is attracted to the surface of the developing roller 73 by the magnetic force of the built-in magnet. That is, the blade plate 145 is positioned with respect to the developing roller 73 by the blade holder 140 attached to the developing unit side plate 132. The blade holder 140 also serves as a casing for the agitator 142 as described above, and improves toner agitation. Accordingly, the blade plate 145 vibrates due to the magnetic force of the magnets arranged inside in polarity by the rotation of the developing roller 73, so that a gap is generated intermittently with the developing roller 73. When the toner is conveyed from this gap by a magnetic force, it is frictionally charged to a positive polarity, and a substantially uniform toner layer is formed on the surface of the developing roller 73. Here, a ring 146 of soft urethane foam for sealing a gap between the developing roller 73 and the developing unit side plate 132 is interposed in the journal portion. Therefore,
The toner is prevented from being scattered or dropped from the gap between the developing roller 73 and the developing unit side plate 132. Further, an under case 147 (here, integrally formed with the casing 139) is provided in order to prevent and catch the toner falling from the developing roller 73 out of the unit due to resonance or the like due to external factors. The developing unit 73 is provided downstream of the developing roller 73 with the same width as the developing unit side plate 132. In the under case 147, a discharging brush 148 for removing a potential remaining on the surface of the developing roller 73 after development is provided.
It is provided over substantially its entire length in contact with the surface. Further, since the upper opening of the under case 147 is provided at the position where the developing roller 73> the photosensitive member 20, the falling toner is transferred to the developing roller 73 side where the airflow is large (the linear velocity ratio is 4: 4).
Will flow into 1).

Further, in order to transfer the toner on the surface of the developing roller 73 to the photoreceptor 20 side for development, the electrode plate 149 provided on the developing unit side plate 132 is grounded via the electrode pin 150, while this electrode is supplied from the main body developing bias power supply. By applying a voltage to the developing roller 73 via the pin 150, a potential difference is provided. Further, although a potential remains at a portion corresponding to the paper background on the surface of the photoreceptor 20 after the exposure, the transfer of the toner is prevented by transfer control of the toner by controlling the application of the developing bias voltage. Is prevented.

By the way, the toner in the unit is consumed by repeating such a developing process. The consumption state is detected by a toner end sensor 151 provided in the main body. This toner end detection will be described with reference to FIGS. 22 and 23. First, the gear 1 is mounted on the axis of the agitator 142.
52 are provided. The gear 152 has a groove, and a spring 1 for engaging with the agitator 142 is provided on the inner peripheral portion.
53 are interposed. Further, a disk 154 which is engaged with the spring 153 and the shaft of the agitator 142 and has a cutout 154a is provided. A roller 157 of an actuator 156 urged by a spring 155 is
Are provided so as to roll freely. As a result, when toner is present, the agitator 142 causes the gear 152 to move due to the toner load.
Rotate later. Therefore, the notch 1 of the disk 154
54a and the groove of the gear 152 remain disengaged (Fig. 22 (a)
And the state shown in FIG. 23 (a)), the roller 157 follows the outer circumference of both. On the other hand, when the toner runs out, the agitator
Since the load on 142 is reduced, the notch 154a of the disk 154 matches the groove of the gear 152 (the state shown in FIGS. 22 (b) and 23 (b)), and the rollers 157 are fitted. The actuator 157 turns on the photo interrupter type toner end sensor 151. Then, the toner supply display is turned on.

By the way, the driving of the developing device 23, in particular, the rotational driving of the developing roller 73 is directly driven by the driving motor 75, and as shown in FIGS.
The gear 161 of the developing roller 73 is substantially directly connected to the drive gear 160 on the shaft via gears 162a and 162b having different diameters. In addition,
Other members in the developing device 23, that is, the agitators 142 and 2
The sheet blade rollers 143 and 144 are driven via gears 164, 165, 166, 167a, 167b and 152 in addition to a gear 163 having a different diameter from the gear 161. The gear 165 is provided on the axis of the two blade roller 144, and the gear 166 is provided on the axis of the two blade roller 143.
152 is provided on the agitator 142 shaft as described above. On the other hand, the driving members in each of the process units other than the developing device 23 are also driven by using the one driving motor 75 as a driving source. However, as shown in FIG. It is driven via relay transmission means 168 by a group of gears. As described above, since the driving of the developing roller 73 is performed irrespective of other process units in a state where the driving of the developing roller 73 is substantially directly connected to the driving motor 75, vibrations of other units and the like are not transmitted to the developing roller 73 ( Without resonance),
Development defects such as image density pitch unevenness are also prevented.

[Sheet feeding section of transfer sheet feeding / conveying device 29] ... FIGS. 25 to 32
See figure.

The transfer paper feeder 29 is provided immediately below the photoconductor 20. First, the paper feed table 3 is supported by unit side plates 170 on both sides via a support shaft 171 so as to be rotatable and openable. At this time, a sector gear 172 is provided on the support shaft 171 and meshes with an oil damper gear 173 fixedly supported on the unit side plate 170 to form a gear damper. Further, a lock member 174 is provided on the unit side plate 170, and hooks protrudingly formed on both sides of the sheet feeding table 3 are provided.
When the 175 is disengaged, it is locked or unlocked and can be opened. That is, when the outer surface of the closed sheet feeding table 3 is manually pushed, the hook 175 is pressed.
Is released from the lock member 174 and the lock is released, and the sheet feeding table 3 is linearly and semi-automatically opened by the engagement of the sector gear 172 and the oil damper gear 173 with the support shaft 171 as the center of rotation. At this time, the safety switch 32 is pressed by a part of the sheet feeding table 3 to be turned on, and the AND operation with the ON signal of the switch 31 causes a warm-up state. Further, the sheet feeding table 3 is positioned in an open state when a part thereof comes into contact with a stopper 176 provided on the main body side.

Here, in the open sheet feed table 3, similarly to the case of the document transport table 1, a pair of side guides 13 are provided.
Are configured to move in the width direction in conjunction with each other by a combination of the rack gears 177, 178 and the pinion gear 179.
Further, a friction pad 16 provided at the center of the innermost portion of the sheet feeding table 3 is paired with the call roller 15 to reliably feed the loaded transfer sheet to the last sheet.

The transfer paper is set on the paper feed table 3, and a paper feed solenoid 180 provided on the unit side plate 170 is turned on by a document leading edge detection signal on the document feed / conveyance side, and the clutch pawl 181 is turned on.
The pawl 181a moves away from the sleeve 182, the pawl 181b moves away from the convex portion 183, and the driving force from the main motor 75 is transmitted to the calling roller 15 via the feed roller 55 and the square belt 184, and the feed clutch 185 are transmitted to the cam portions 186, and each of them is rotationally driven. The sector gear 1 in which the pin 187a is joined to the outer periphery of the cam portion 186 by rotating the cam portion 186
87 rotates counterclockwise, causing the pickup arm 189 to rotate clockwise via the pinion gear 188. The pick-up arm 189 has a cam shape, and supports 190 of the call-out roller 15 (which can rotate around the axis of the paper feed roller 55).
The arm 191 connected to is in pressure contact. Therefore,
When the pickup arm 189 rotates clockwise, the call roller 15 is displaced downward on the transfer paper. Further, the shaft of the tip fence 32 is connected to the pickup arm 189 via a pinion gear 192 and a sector gear 193, and the tip fence 35 is rotated in a state in which the tip fence 35 is tilted forward by the clockwise rotation of the pickup arm 189. Then, the transfer paper can be fed. Further, when the cam portion 186 rotates, the sector gear 187 rotates clockwise, so that the calling roller 15 is displaced upward and the front fence 35 is returned to the raised state. This prevents double feeding.

Here, the operation of the feed clutch 186 and the cam portion 186 is such that when the paper feed solenoid 180 is turned on, the clutch pawl 181b separates from the convex portion 183 and the cam portion 186 moves counterclockwise as shown in FIG. Rotate in the direction. Also, clutch claws 181a
Also leaves sleeve 182. When the cam portion 186 further rotates, as shown in FIG.
At 81c, the rotation of the cam portion 186 is stopped. At this point, the sector gear 187 has completed one reciprocating operation, and the calling roller 15 has finished ascending. When the sheet feeding solenoid 180 is turned off, the clutch pawl 181b hits the convex portion 183 and the clutch pawl 181a also engages the sleeve 182 as shown in FIG. 30 (c).

Next, the separation sheet feeding operation will be described with reference to FIG. First, the front fence 35 is tilted forward, and the call roller 15 contacts the transfer paper 195 on the paper feed table 3. The rotation of the call roller 15 is transmitted to the transfer paper 195, and the friction pad 1
6, only one sheet is fed from the sheet feeding table 3. The fed transfer paper 195 is continuously transported by the feed roller 55 as it is, and by the rotation of the cam portion 186 of the feed clutch 186, the call roller 15 separates from the transfer paper, and the front fence 35 rises, and the next transfer is performed. Feeding out of the paper 195 is prevented. Then, the sheet feeding solenoid 180 is turned off in a state where a certain amount of slack is given by the detection of the registration sensor 62, and the apparatus stands by to synchronize with the visible image on the photoconductor 20.

Also, when not in use, the paper feed table 3 is lifted by manual and rotated in the closing direction,
The hook 175 is engaged with the lock member 174 and locked in a closed state.

[Near transfer charger 24] ... see FIGS. 33 to 35.

The transfer charger 24 has a transfer roller just below the photoreceptor 20.
It is arranged facing 72. A registration roller 60 is supported at a position upstream of the transfer charger 24 with respect to the main body side plate 85 via a bearing 200. A transfer casing 201 fitted and supported by the slice portion of the bearing 200 and rotatable by its outer diameter is provided. A driven roller 61, which is driven to rotate while being opposed to the registration roller 60, is provided at an opening of the transfer casing 201 via a bearing 202 and a bracket 203, and serves as a lower guide for transfer of the transfer paper. The transfer paper 195 conveyed by the pair of registration rollers 60 and driven rollers 61 is in close proximity to the photoconductor 20 and has a transfer casing 2 provided with a mylar 204 serving as an entrance guide.
Guided by 01. The Mylar 204 has a convex central portion in the width direction so that the transfer paper surface follows the transfer paper uniformly so that the leading end of the transfer paper is synchronized with the visible image on the photoconductor 20. Further, the transfer casing 201 is provided with an end block 206 for holding both ends of a charge wire 205 for discharging the opposite polarity to the toner in a stretched state at a position of 20 ± 0.2 mm just below the center of the transfer roller 72. As a result, the transfer paper 195 is electrostatically attracted and conveyed in opposition to the visible image, so that the toner image on the photoconductor 20 is transferred to the transfer paper 195 side.

Here, in the transfer casing 201, the transfer charger 2
A nylon wire 207 is stretched in the opening portion 4 in such a manner that the nylon wire 207 expands in the paper transport direction in order to prevent the transfer paper from getting into the inside.

After the transfer, the transfer paper 195 needs to be separated from the photoconductor 20. In this regard, the transfer roller is generally separated by a separation charger or the like.
It is separated by a curvature of 72, and does not require separate dedicated peeling means. Guide fins 208 for guiding the transfer paper 195 separated from the photoreceptor 20 after the transfer to the fixing nip portion of the fixing device 25 are attached using a part of the transfer casing 201 similarly to the nylon wire 207. .

[Fixing device 25] ... see FIGS. 1, 36 and 37.

The fixing device 25 heats and fixes unfixed toner on the transfer paper 195 entering from the transfer unit side by a roller pair of a fixing roller 63 and a pressure roller 64. It is arranged at the near side position. First, the fixing roller 63 has a gear 210 rotatably driven by a drive motor 75 on its shaft, and is supported by the unit side plate 170 via a slide bearing 211. The pressure roller 64 is slidably supported up and down on the unit side plate 170 via a slide bearing 212, and is pressed against the fixing roller 63 by a pressure lever 214 with a spring 213 engaged. You are being biased to. The transfer paper 195 is such a roller 6
When passing through 3,64 pairs, it is fixed under a certain temperature (180 to 185 ° C.) and a certain pressure (18 to 21 kg).

Here, as the fixing roller 63, a thin-walled Al tube roller having a high thermal conductivity and integrally coated with a fluorine resin is used, and the fixing heater 33 is built in the shaft center. Both ends of the fixing heater 33 are provided with bracket terminals 215.
It is energized while supported by. At this time, in order to improve the thermal efficiency, the inner wall surface of the fixing roller 63 may be coated with black paint or the like.

In this embodiment, a thermistor 220 for controlling the temperature of the fixing heater 33 by contacting a part of the upper peripheral portion of the fixing roller 63 is provided. Further, a thermostat 221 for preventing the temperature of the fixing heater 33 from excessively rising due to any accident or the like is provided in contact with the upper peripheral portion of the fixing roller 63. More specifically,
The thermistor 220 and the thermostat 221 are mounted and supported at positions separated in the width direction via a heat shield plate 222. The heat shield plate 222 is located near the outer periphery of the fixing roller 63 and reflects radiant heat from the fixing roller 63. Further, a heat insulating cover 224 is provided facing the heat shield plate 222 via a space 223. That is, the periphery of the fixing roller 63 has a two-layer heat insulation structure including the heat shield plate 222 and the space 223. The outer surface side of the heat insulating cover 224 is planted.

The heat insulating cover 224 is provided with a cut-and-bent portion having a plurality of slits (vents) 225 located almost directly above the fixing roller 63, and the two cooling fans 30 are attached and held here. I have. That is, the cut-and-bent portion forms a ventilation hole and also serves as a cooling fan bracket. In addition, the mounting positions of the two cooling fans 30 are as follows:
When viewed in the axial direction of the fixing roller 63, the fixing roller 63 is located between the copy minimum size end and the copy maximum size end. Furthermore, a first duct 2 that shields the heat insulating cover 224 including the cooling fan 30 over almost the entire area is provided above.
26 are provided. The first duct 226 is the photosensitive member 2
The first duct 226 and the heat insulating cover 224 are provided with a heat insulating material 227 such as polyurethane foam, which has a lower opening extended near the transfer position. Is interposed. This allows
Thermal deformation is prevented. In particular, in the present embodiment, the abutment surface, that is, the outer surface of the heat insulating cover 224 is subjected to the flocking process, and the heat insulating effect is high.

Further, the cooling fan 3 is provided above the first duct 226.
A pair of left and right third ducts 228 and 229 are provided to communicate with the exhaust port side 0 and guide the exhaust flow to the outside of the machine. Filters 230 are provided near the exhaust outlets of these third ducts 228,229.

In addition, a second duct 231 for intake whose upper opening extends toward the vicinity of the position of the charger 21 is provided at a central upper portion of the first duct 226, and the front cover 2 serving as an exterior cover is provided. A duct is formed by fitting with a rib 232 formed on the back surface (see FIG. 14).

According to the heat insulating / cooling configuration around the fixing roller 63 of the present embodiment, the radiant heat of the fixing roller 63 is maintained in the first air layer by the heat shield plate 222, and the heat of the space 223 serving as the second air layer is protected by the heat insulating cover. Absorbed by 224. At this time, the heat shield plate 222 has a duct shape, and the air whose temperature has increased due to the suction of the cooling fan 30 is the first, second, and third ducts 226, 231, 228, and 2
Since the air is exhausted outside the apparatus by 29, the temperature rise of each part located on the surface of the photoconductor 20 can be prevented. In particular, according to this embodiment, since the first duct 226 is formed by using the casing 79, a cooling effect on the photoconductor 20 is also exerted. Further, ozone O ₃ generated from the transfer unit can also be sucked and exhausted by the cooling fan 30 and the first and third ducts 226, 228, 229, and the ozone O ₃ and the photosensitive layer on the surface of the photoconductor 20 due to the temperature rise are increased. Deterioration can be prevented.

A plurality of peeling claws 65 for peeling the fixed transfer paper 195 from the fixing roller 63 and guiding it toward the paper discharge roller 66 are rotatably provided, and are urged toward the fixing roller 63 by a spring 240. . The paper discharge rollers 66 are arranged near the pressure roller 64 and are supported by a guide plate 241 which also serves as an exterior cover. In addition, a paper ejection sensor 67 is also provided in proximity to the paper ejection roller 66 by using the guide plate 241 to be used for detecting the transfer paper transport time from the registration position, and to take care of the jam detection in this span. Have been.

By the way, if the transfer paper 195 is stopped due to some accident at the fixing nip portion between the fixing roller 63 and the pressure roller 64, the transfer paper 195 meshes with the gear 243 provided on the shaft of the pressure roller 64. The knob 245 having the gear 244 to be rotated may be manually rotated.

Further, for processing when the transfer paper 195 is stopped at a position in front of the fixing nip portion, first, a pressing spring 213 engaged with the unit side plate 170 and a pressing lever 214 for the pressing roller 64 are connected to a relay. A matching bracket 247 is provided. The bracket 247 has a lock lever 249 fitted to a positioning pin 248 provided by caulking on the main body side plate 85.
Are connected by a pin 250. Further, a handle 251 is fixed to the front center of the bracket 247. Therefore, when the user grips the handle 251 and pulls the bracket 247 forward, the lock lever 249 rotates counterclockwise to disengage from the positioning pin 248, and the lock is released. When the lock is released, the units of the transfer sheet feeding and transporting unit and the fixing unit supported by the unit side plate 252 are moved to the near side via the guide 253 provided on the main body side plate 85 and guiding the movement of the pin 250. Slide. At this time, a lever 254 having one end connected to the pin 250 is slidably held in the longitudinal direction of the lever 254, and the other end is connected to the main body side plate 85 by the pin 255.
36 also moves integrally, but since the pin 255 is guided by the guide hole 257 of the main body side plate 85, a state shown by a dashed line in FIG. 36 results. Also, when the unit side plate 252 moves to the near side,
The support member 259 provided on the main body belt 258 also moves to the near side. A pin is provided between the support member 259 and the unit side plate 252.
The rotation lever 261 is interposed by the 260 so that the unit including the unit side plate 252 can be rotated downward about the pin 260 in a state of being pulled out toward the user. Therefore, by rotating the unit in the vicinity of the paper feed unit downward as shown by the two-dot chain line in FIG. 37, the reverse conveyance path 59 surface is largely exposed,
The transfer paper 195 can be removed. In this open state, the unit is held by the levers 254 and 256 extending to the state shown by the two-dot chain line.

In addition, since it is supported by the guide 253 at the time of wearing after opening for such a jam processing, it is guided in the closing direction as it is, and the lock lever 249 engages with the positioning pin 248 by the action of the pressure spring 213, Locked again. During such mounting, the transfer charger 24 is
The plate 20 is pressed by a leaf spring 262 (shown in FIG. 5) provided on the casing 79 and positioned.

[Cleaning device 26] ... see FIGS. 38 and 39.

The cleaning device 26 is for cleaning and removing the toner remaining on the photoconductor 20 after the transfer process by the blade 51, and is disposed on the upper front side with respect to the photoconductor 20. Here, the blade 51 is supported by a bracket 270, and the bracket 270 is pressed by a spring 271 provided in a casing 79 so that the blade 5
One end is in pressure contact with the photoconductor 20 on the cleaning roller 71. The bracket 270 is attached to the casing 79 with a locking pin 2
The blade 51 is rotatably provided via 72, and positions the tip of the blade 51. Since the toner is scraped off from the casing opening at the blade 51 and falls, a mylar 273 is provided at a leading end position under the opening as a guide member for preventing the toner from falling out of the casing 79. Further, the casing 79 is provided with a spring 275 for pressing the bearing 274 of the tension roller 74 to apply tension.

[Electrical components and their circuit configuration] ... see FIG.

First, an interlock switch 301, a noise filter 302, and a main switch 30 are connected to the AC line for the AC power supply 300.
3. The triac 304, the thermostat 221, the fixing heater 33, the drive motor 75, and the two cooling fans 30 are connected. A power pack 307 for the transfer charger 24 is connected to a DC line of a DC power supply 306 connected to an AC line via a power transformer 305. In addition, the DC22V line has a total counter 309, a sheet feeding solenoid 180, and a registration solenoid 310 via a relay board 308.
Is output to The relay board 308 is a main PC board 311
4 connected to the above 22V line
3, the output control of the fluorescent lamp stabilizer 312, the power pack 313, the static elimination LED array 27, and the fluorescent lamp heater 34 is performed. Pad pack
Reference numeral 313 supplies power to the charging charger 21 via the varistor 120. Relay board for DC5V line
The paper feed sensor 36, the paper discharge sensor 67, and the thermistor 220 are connected via 308. Similarly, the main PC board 311 controls the output of the automatic light control sensor 103, the collected toner sensor 314, the joint sensor 53, the pulse generator 315, and the toner end sensor 151 for the 22V line.

Advantageous Effects of Invention As described above, the present invention provides a cooling fan for cooling the inside of the apparatus, covers the entire heat insulating cover covering the upper space of the fixing roller, and has an opening extending near the transfer position. Since the first duct, the second duct for the intake air whose opening extends near the charging position, and the third duct communicating with the exhaust side of the cooling fan and guiding the exhaust air to the outside are provided, Ozone generated around the photoreceptor by the charging means and the transfer means in the image forming process can be forcibly and efficiently exhausted by the intake / exhaust flow of the cooling fan using these first to third ducts as guides. In this case, a cooling fan is used to prevent a rise in the temperature inside the apparatus due to a fixing roller with a built-in heat source.A dedicated fan is not required for exhausting ozone. Around the fixing roller, functions of cooling and exhausting ozone can be exhibited by the cooling fan and the duct.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is a front view showing the vicinity of a fixing portion with a part cut away, FIG. 2 is an external perspective view of a copier when not in use, and FIG. Appearance perspective view, 4th
The figure is a schematic side view of the whole, FIG. 5 is an external perspective view of the photoconductor,
FIG. 6 is a schematic side view mainly showing the photoconductor, FIG. 7 is a front view mainly showing the photoconductor shown partially cut away, FIG. 8 is a front view partially shown cut away, and FIG. FIG. 10 is a plan view of a document conveying table portion, FIG. 11 is a schematic side view of an exposure optical system, FIG. 12 is a schematic plan view thereof, and FIG. 13 is a part thereof. FIG. 14 is a schematic side view of the vicinity of the charging / discharging unit, FIG. 15 is a schematic plan view of a part thereof, FIG. 16 is a front view of the part thereof, FIG.
17 is a schematic plan view near the charging charger, FIG. 18 is an exploded perspective view near the charging charger, FIG. 19 is a front view thereof, and FIG.
20 is a schematic side view showing the vicinity of the developing device, FIG. 21 is a front view of the developing device with a part cut away, FIG. 22 is a side view showing a toner end detecting operation, FIG. FIG. 24 is a side view of a drive transmission system for the developing device, FIG. 25 is a schematic side view of a portion near a transfer sheet feeding portion shown partially cut away, FIG. 28 is a front view, FIG. 29 is a perspective view, FIG. 30 is a partial perspective view thereof, and FIG. 31 shows a sheet feeding control operation. FIG. 32 is a side view showing the sheet feeding operation, and FIG.
FIG. 33 is a plan view near the transfer portion, FIG. 34 is a side view thereof, and FIG.
FIG. 36 is a partially cutaway front view, FIG. 36 is a partially cutaway side view of the vicinity of the fixing portion, FIG. 37 is a side view showing an opening operation at the time of a jam, and FIG. 38 is partially cutout. FIG. 39 is a side view of the cleaning device, FIG. 39 is a front view thereof, and FIG. 40 is a block diagram showing electrical components and a circuit configuration thereof. 20 photoreceptor, 21 charging means, 23 developing means, 24
.. Transfer means, 30 cooling fan, 33 heat source, 63 fixing roller, 224 heat insulating cover, 226 first duct, 22
8,229 3rd duct, 231 2nd duct

Claims (1)

(57) [Claims] An endless belt-like photoreceptor is charged uniformly by a charging means, and then an electrostatic latent image is formed on the photoreceptor. The latent image is visualized by a developing means. In an electrostatic recording apparatus in which transfer is performed on transfer paper by a transfer unit and the transferred image is fixed by a fixing unit having a fixing roller having a built-in heat source, a cooling fan for cooling the inside of the apparatus is attached. A heat insulating cover that covers an upper space of the fixing roller, a first duct for air intake that has an opening extending near a transfer position of the transfer unit and that covers the entire heat insulating cover including the cooling fan; A second duct for intake air having an opening extending near the charging position of the charging means and communicating with the cooling fan is provided, and the exhaust flow is communicated with the exhaust side of the cooling fan to guide the exhaust flow out of the machine. 3rd da Electrostatic recording apparatus characterized by comprising bets.