JP2003084632A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a distinct electrostatic latent image on the surface of a photoreceptor drum and to avoid the deterioration of recorded image quality by preventing a situation that the flow of air going toward a fixing unit from a developing unit is formed and suspended toner gets on the air and adheres to the lens of an optical writing means in the constitution of the image forming device where forced ventilation is performed by a ventilating fan in order to discharge heat from the fining unit whose temperature gets high and the periphery of a power source part to the outside of the device. SOLUTION: A shielding piece 8a is provided hanging from an intermediate cover 8, and a rib 37 is provided projectingly on the upper surface of the housing 36 of a photoreceptor unit 15 on a device main body side. A sponge 38 is provided to be stuck to the lower surface of the piece 8a, and the sponge 38 and the rib 37 are arranged to be opposed to each other. The sponge 38 is made to be pressed and brought into contact with the rib 37 in a state where the cover 8 is closed so as to cut off space around the fixing unit 22 and space above the photoreceptor unit 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus.

[0002]

2. Description of the Related Art Generally, in an electrophotographic image forming apparatus such as a facsimile machine, a charger for uniformly charging a photosensitive drum, and a surface of the photosensitive drum are irradiated with light to form an electrostatic latent image. And a developing device for adhering toner to the electrostatic latent image to form a toner image, and a transfer device for transferring the toner image formed on the photoconductor to a sheet. In the developing device, after the toner image is transferred onto the sheet, the residual toner adhering to the photoconductor is removed by using a cleaning device, and then the developing device is adapted to correspond to the action of the next image formation. Is common. On the other hand, without disposing the cleaning device, the toner remaining on the photoconductor is collected in the developing device,
It is also practiced to use a cleanerless mechanism of the type to be reused.

In the cleanerless type image forming apparatus, a process unit for forming a toner image and transferring the toner image on a sheet is constructed as follows, for example. As shown in FIG. 3, the developing device unit 14 provided in the process unit 13 includes an agitator for agitating the toner in the toner chamber 19 for accommodating the toner, a developing roller 20 arranged corresponding to the photoconductor, and a developing roller 20. A supply roller 21 that supplies toner to the developing roller 20 while charging it, and a blade that forms the toner attached to the surface of the developing roller 20 as a thin layer are arranged. The supply roller 21 and the developing roller 20 are driven in the same direction while being pressed against each other, so that the toner is frictionally charged between the two rollers 20 and 21, and the toner is attached to the surface of the developing roller 20. . Then, the toner attached to the surface of the developing roller 20 is formed as a thin layer having a constant thickness by being pressed by the blade, and the photosensitive drum 1
It is exposed toward the developing position with respect to 6.

The photoconductor unit 15 combined with the developing unit 14 is provided with a photoconductor drum 16 and a charging roller 18 for uniformly charging the photoconductor drum 16. The body drum 16 is connected to the ground of the body frame and grounded. Also,
A memory removing member composed of a brush is provided below the frame of the photoconductor unit 15 to disturb the toner remaining on the photoconductor to weaken the adhesion force of the toner.

[0005]

However, as shown in FIG. 12, around the photosensitive drum 16, for example,
In many cases, the toner wound up by the charging roller 18, the toner weakly transferred from the developing device unit 14, and the like become a cloud inside the housing 36 and float. In particular, when a brush roller is used as the charging roller 18, the peripheral speed of the brush roller is determined by the photosensitive drum 16
Since it is often set to be higher than the peripheral speed, the toner is more likely to be rolled up and floated. Further, in the case of the cleanerless mechanism, the memory drum removing means is used for the photosensitive drum 1.
By agitating the residual toner on the roller 6, the adhesion of the residual toner to the drum is weakened, the charging roller 18 easily winds up more toner, and the floating toner also increases. Then, such scattered toner rides on the air flow affected by the rotation of the photoconductor drum 16, and the air flow becomes L
There is a problem that the toner flows to the light output portion of the ED head array 31 and adheres to the light output portion.

A fixing unit 22 is provided on the downstream side of the process unit 13 (downstream side in the sheet conveying direction), and the sheet after transfer is fed to the fixing unit 22. The fixing unit 22 includes a heat roller 23 including a heat source such as a halogen lamp, and the heat roller 23.
A press roller 24 that is in pressure contact with the sheet, and presses the fed sheet toward the heat roller 23 by the press roller 24, and heats and melts the toner transferred onto the sheet by the heat roller 23 to fix the toner. I am trying to do it. Since the heat roller 23 becomes high in temperature, an exhaust fan 48 is provided on the side of the fixing unit 22 to forcibly discharge the heat generated here to the outside of the apparatus.

By the exhaust fan 48, not only the air flow that flows in the axial direction of the heat roller 23 but also the exhaust fan 48 from each device inside the apparatus around the fixing unit 22.
An air flow heading for is also created. In particular, this latter air flow removes the toner floating in the developing unit 14 from the LE.
There is a problem that the toner is attached to the light output portion of the D head array 31 by the air flow of the exhaust fan 48 in addition to the air flow caused by the rotation of the photosensitive drum 16.

Further, as shown in FIGS. 12 and 13, when the exhaust fan 48 is rotated, a negative pressure is applied to the outside of the casing 36 with respect to the inside thereof, and the slit 36a provided on the upper surface of the casing 36 The toner floating inside the housing 36 tries to flow out from the gap between the LED head array 31 inserted into the slit 36a. Since the light output portion of the LED head array 31 is located on the path through which the floating toner flows out, and the photoconductor drum 16 is negatively charged, the LED head array 31 arranged opposite thereto is positive. Therefore, when the floating toner approaches the LED head 30, electrostatic force also acts to accelerate the adhesion of the toner to the light output portion.

As described above, in the writing device for writing with a relatively weak light such as the LED head array 31, when toner adheres, the problem that the writing action on the photosensitive drum 16 cannot be performed easily occurs. . However, this writing device is not designed to remove dirt during normal image forming operation, except for special cleaning. If the image forming operation is continued, the quality of the formed image deteriorates.

As described above, in the present invention, the photosensitive drum 1
It is an object to prevent the toner carried by at least one of the air flow caused by the rotation of 6 and the air flow caused by the exhaust fan 48 from adhering to the photodetection section of the LED head array 31.

[0011]

The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be described. That is, in the image forming apparatus including the developing unit, the photoconductor unit, and the fixing unit as described in claim 1, and the writing unit is projected in the photoconductor unit, the photoconductor unit and the writing unit are provided. An airflow blocking means is provided between the mounting unit and the mounting substrate that supports the unit to prevent an airflow from the developing unit toward the fixing unit.

According to a second aspect of the present invention, there is provided an image forming apparatus comprising a developing unit, a photoconductor unit, and a fixing unit, and a writing unit protruding in the photoconductor unit. Airflow blocking means is provided in the gap between the writing means and the airflow from the inside of the photoconductor unit to the outside is prevented.

More specifically, as described in claim 3, the airflow blocking means according to claim 1 or 2 is composed of a sealing member composed of a projecting piece and an elastic body abutting against the projecting piece. One of the projecting piece and the elastic body is provided on the writing means or its mounting substrate, and the other is provided on the side of the photoconductor unit.

Alternatively, as described in claim 4, the photosensitive member unit according to claim 1 or 2 has at least a photosensitive drum and a casing for supporting the drum,
The housing is formed with a slit into which the writing means is inserted.

According to a fifth aspect of the present invention, in an image forming apparatus having a developing unit, a photoconductor unit, and a fixing unit, in which the writing unit is projected in the photoconductor unit, the writing unit is provided. A sheet-like member is vertically provided around the periphery.

[0016]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will now be described with reference to the facsimile apparatus 1. In the following description, it is assumed that the direction of arrow A shown in FIG. 1 is the front (front side) of the facsimile apparatus 1 and the front-rear and left-right positions of each structure are described.

FIG. 1 is an overall perspective view of the facsimile machine 1. As shown in FIG. 1, the main body of the facsimile machine 1 is placed and fixed on a paper feeding device 5, and the image reading device 3 is installed in the main body. The image recording device 4 is arranged vertically. In the present embodiment, a laser printer is adopted as the image recording device 4, the details of which will be described later.

An automatic document feeder (hereinafter referred to as "ADF") 6 is attached above the image reading device 3, and an exterior cover 7 is provided in front of the ADF 6 so as to be freely opened and closed with respect to the main body of the facsimile device 1. Has been. The upper surface of the exterior cover 7 is used as a document discharge tray 10.
The paper feed tray 9 is provided on the top of the paper tray 0. Then, the originals set in the paper feed tray 9 are separated one by one and AD
The image is taken into the inside of F6 and the image is displayed on the C of the image reading device 3.
It is read by a CD and discharged to the discharge tray 10.

Then, the read image is converted into a digital signal (image information) and transmitted to the other party via a telephone line. Further, the image information received from the other party is processed by the image recording device 4 and transferred to the paper taken in from the paper feeding device 5. Alternatively, the image read by the image reading device 3 can be directly transferred to a sheet by the image recording device 4 without being transmitted (a so-called copy function).

Further, FIG. 2 shows a state in which the outer cover 7 of the facsimile device 1 is opened. As shown in FIG. 2, an intermediate cover 8 is provided therein to cover the image recording device 4. There is. The rotation fulcrum shaft of the exterior cover 7 and the rotation fulcrum shaft 11 of the intermediate cover 8 are arranged in directions orthogonal to each other, and the exterior cover 32 opens and closes in the left-right direction, whereas the intermediate cover 8 It is configured to open and close in the front-back direction. Therefore, the exterior cover 7 and the intermediate cover 8
The cover 7 is accidentally opened from the state where both are open.
Even if is closed, the intermediate cover 8 will not be pressed and closed.

3 and 4 are side cross-sectional views of the image recording apparatus 4, showing a state in which the intermediate cover 8 is closed and a state in which the intermediate cover 8 is open, respectively. As shown in both figures, a process unit 13 is arranged below the intermediate cover 8,
The process unit 13 is configured by combining a developing unit 14 and a photoconductor unit 15 which form an image recording unit.

The photoconductor unit 15 includes a photoconductor drum 16 that comes into contact with a sheet and transfers toner, a housing 36 that houses the photoconductor drum 16, and a surface of the photoconductor drum 16 that is charged to a negative potential. And a charging roller 18 for controlling the charging. In addition, a slit 36 is formed in the left-right direction on the upper surface of the housing 36.
A is opened, and the optical writing means described later is inserted.

The developing unit 14 includes a toner chamber 19 for containing toner, a developing roller 20 for supplying the toner to the photosensitive drum 16, and a supplying roller 21 for supplying the toner to the developing roller 20.

A fixing unit 22 is provided behind the process unit 13 (downstream in the sheet feeding direction), and the fixing unit 22 includes a heat roller 23 and a heat roller 23.
And a press roller 24 arranged to face the heat roller 23.

Above the photoconductor unit 15,
The intermediate cover 8 as the mounting substrate has an optical writing means L
The ED head 30 is provided horizontally. The LED head 30
Is an LED head array 31 having a large number of light emitting portions arranged in a line in the width direction of the paper, and a SELFOC (registered trademark) lens 32 for condensing light from the LED head array 31 on the photosensitive drum 16. And is fastened with screws 33 from below. Since the SELFOC lens 32 has a short focal length, it needs to be arranged close to the photosensitive drum 16. Further, the surface of the lens may be coated with an antistatic agent to prevent the lens from being charged. When the intermediate cover 8 shown in FIG. 3 is closed, the LE
The SELFOC lens 32 of the D head 30 is inserted into the slit 36a of the housing 36 of the photoconductor unit 15 and projects downward (to the photoconductor drum 16 side), and the LED head 30 is read by the image reading device 3. The LEDs on the LED head array 31 are caused to emit light based on the image information (when the copy function is used) or the received image information (when the facsimile function is used). The SELFOC lens 32 forms an image of the light emitting point of the LED on the photoconductor drum 16, and an electrostatic latent image is formed on the photoconductor drum 16.

Then, toner is attached to the electrostatic latent image on the photosensitive drum 16 to form a toner image, and the toner image is formed on the sheet fed from the sheet feeding device 5 to the image recording device 4. It is designed to be transferred sequentially. The sheet on which the toner image is transferred is sent to the fixing unit 22, and the press roller 24 is pressed toward the heat roller 23, so that the toner transferred on the sheet is heated by the heat roller 23.
It is heated and melted by means of and fixed on paper as a permanent image. The sheet fixed with the toner is discharged from the inside of the image recording apparatus 4 by the discharge rollers 25 and 26 arranged on the downstream side (rear side) of the heat roller 23.

By the way, around the photosensitive drum 16, for example, the toner wound up by the charging roller 18, the toner weakly transferred from the developing unit 14, and the like cover the image recording device 4 and the upper part thereof. In the space formed between the cover 8 and the cover 8, it often becomes a cloud and floats freely. In particular, when the brush roller 35 (see FIG. 5) is used as the charging roller 18, the peripheral speed of the brush roller 35 is often set higher than the peripheral speed of the photosensitive drum 16, so that the toner Winding up and more floating.

In the case of the cleanerless mechanism, the residual toner on the photosensitive drum 16 is agitated by the memory removing means to weaken the adhesion of the residual toner to the drum and the charging roller 18 collects more toner. It will be easier to wind up and the amount of floating toner will increase. Then, such scattered toner may flow on the air flow affected by the rotation of the photoconductor drum 16, the air flow may flow to the LEDs of the LED head array 31, and the toner may adhere to the LEDs. is there.

Further, since the heat roller 23 becomes high in temperature when fixing the toner transferred onto the sheet, an exhaust fan 48 is provided on the side of the fixing unit 22 so that the heat generated here is discharged to the outside of the apparatus. It is forcibly discharged. By the exhaust fan 48, not only the airflow flowing in the axial direction of the heat roller 22 but also the airflow directed to the exhaust fan 48 from each device in the apparatus around the fixing unit 22 is generated. In particular, this latter air flow is due to the developer unit 1
The toner floating in 4 is led to the LEDs of the LED head array 31, and the toner wound up by the rotation of the photosensitive drum 16 is led to the outside of the housing 36.
As described above, the toner adheres to the LEDs not only by the air flow generated by the rotation of the photosensitive drum 16 but also by the air flow generated by the exhaust fan 48. The generation of the airflow from the inside of the housing 36 to the outside is not necessarily caused only by the exhaust fan 48, but is also generated by other factors such as when the outside of the housing 36 has a negative pressure to the inside thereof. To do. Further, since the photoconductor drum 16 is negatively charged, the LED head array 31 arranged opposite thereto is positively charged,
Therefore, when the floating toner approaches the LED head 30, the electrostatic force also acts, which accelerates the adhesion of the toner to the LED.

As described above, in the writing device for writing with a relatively weak light such as the LED head array 31, when toner adheres, the problem that the writing operation on the photosensitive drum 16 cannot be performed well is likely to occur. . However, this writing device is not designed to remove dirt during normal image forming operation, except for special cleaning. If the image forming operation is continued, the quality of the formed image deteriorates.

Therefore, in the present invention, in order to solve the above problems, a shielding piece 8a and a shielding rib 8b are vertically provided from the intermediate cover 8 to cover the front and rear sides of the LED head 30, and the photoconductor of the image recording portion. A rib 37 is projectingly provided on the upper surface of the case 36 of the unit 15. The shielding piece 8a, the shielding rib 8b,
The width of each of the three ribs 37 is substantially equal to the left-right length of the LED head 30 and is provided over the left-right width of the intermediate cover 8, and the shielding piece 8a and the shielding rib 8 are provided.
The lower end of b extends to near the upper surface of the housing 36 of the photoconductor unit 15. Further, a sponge 38, which is an elastic body, is attached to the lower surface of the shielding piece 8a so that the sponge 38 faces the rib 37. The width of the sponge 38 is also L
The ED head 30 is formed to have a length substantially equal to the left-right length, and is horizontally provided on the lower surface of the shielding piece 8a. Alternatively, the arrangement of the sponge 38 and the rib 37 is reversed, and the sponge 38 is attached to the upper surface of the housing 36, and the rib 3
7 may be projected on the lower surface of the shielding piece 8a. Note that rubber or the like may be attached to the lower surface of the shielding piece 8a or the upper surface of the housing 36 instead of the foamed material such as the sponge 38, and the elastic material is not particularly limited.

FIG. 5 is a side sectional view of the photosensitive unit 15 and the LED head 30. As shown in FIGS.
In the state where the intermediate cover 8 is closed, the sponge 38 is pressed against the ribs 37, and the intermediate cover 8 is held at that portion.
And the image recording unit (specifically, the intermediate cover 8 and the casing 36) are sealed, and the space around the fixing unit 22 and the space above the photoconductor unit 15 are separated from each other. To be As a result, the air flow from the developing unit 14 to the fixing unit 22 is blocked, and the photoconductor unit 1
In the space above 5, the air flow by the exhaust fan 48 does not occur, so the floating toner does not flow toward the LED head 30 and the amount of toner adhering to the LED head 30 is reduced.

In the above structure, the air flow mainly by the exhaust fan 48 is prevented, but as described above, another air flow is generated in the housing 36 by the rotation of the photosensitive drum 16. As shown in FIG.
There is a possibility that the toner flowing out from a and floating in the housing 36 may adhere to the LED head array 31.

Therefore, as shown in FIG. 6, sheet-shaped members such as films 41, 41 are hung vertically from the front and rear of the LED head array 31 in the LED head 30. The lateral width of the films 41, 41 is formed to be substantially the same as the left-right length of the LED head 30.
Floating toner flowing toward the ED head 30 is blocked, and adhesion to the LED head array 31 is prevented. At this time, the airflow generated by the rotation of the photosensitive drum 16 is blocked by the films 41, 41,
Since the toner flows in the circumferential direction of the photoconductor drum 16 so as to sew between the lower end of 41 and the photoconductor drum 16, the toner flowing along with the air flow is emitted from the LED head array 31.
Hardly adheres to. Further, when the sheet-like member is formed of a material having a polarity opposite to that of the toner and easily charged to plus, for example, glass, aluminum, iron, or the like, it is possible to more effectively prevent the floating toner from adhering to the LED head array 31. You can That is, the floating toner is adsorbed to the sheet-shaped member made of these materials before reaching the LED head array 31, and is prevented from adhering to the LED head array 31. Alternatively, a current having a polarity opposite to that of the toner may be applied to the sheet-shaped member to positively charge the toner so that the toner easily attaches.

The film 41 may be arranged only on the rear side of the LED head array 31, and since the film 41 does not cause an air flow entrained by the photosensitive drum 16 immediately below the LED head array 31. The toner hardly adheres to the LED head array 31.

As another embodiment, as shown in FIG. 7, a film 42 is hung vertically from the front surface of the LED head 30. Alternatively, as shown in FIG.
The film 43 may be hung vertically from the front surface of the mounting substrate supporting the. The lateral width of the films 42 and 43 is formed to be substantially equal to the lateral length of the LED head 30, and when the intermediate cover 8 is closed, the lower ends of the films 42 and 43 come into contact with the upper surface of the housing 36. The upper portion of the slit 36a is covered, and the space inside the housing 36 and the space above the housing 36 are separated and separated. As a result, the airflow generated by the rotation of the photoconductor drum 16 does not flow out from the slit 36a, but flows in the substantially circumferential direction along the photoconductor drum 16. Therefore, the toner flowing along with the air flow hardly adheres to the LED head array 31.

As another embodiment, as shown in FIG. 9, a recess 36b is provided around the slit 36a formed in the housing 36, and the sponges 39, 39 are provided in the recess 36b.
When an elastic body such as is attached and the intermediate cover 8 is closed, L
The ED head 30 comes into contact with the sponges 39, 39, and the space inside the housing 36 and the space above the housing 36 are separated and separated. As a result, the airflow generated by the rotation of the photosensitive drum 16 does not flow out from the slit 36a,
It flows along the photosensitive drum 16 in a substantially circumferential direction. Therefore, the toner flowing along with the air flow hardly adheres to the LED head array 31. Alternatively, the sponges 39 may be attached to the lower surface of the LED head 30, and the sponges 39 may contact the upper surface of the recess 36b of the housing 36 when the intermediate cover 8 is closed. . The recess 36 of the housing 36
b, or a sponge 39.
Rubber or the like may be attached instead of the foamed material such as 39 and is not particularly limited as long as it is an elastic body.

As described above, in the embodiment shown in FIGS. 6 to 9, L
An air flow blocking means including an elastic body such as a sponge 39 and a sheet-shaped member such as films 41, 42, and 43 is provided on the front rear side or the front rear side of the ED head 30. As shown in FIG.
Air flow blocking means may also be provided on the side of 0.

As shown in FIGS. 12 and 13, on the left side of the LED head 30, since the exhaust fan 48 is disposed obliquely rearward of the LED head 30, the slit 36a into which the LED head array 31 is inserted is formed. If there is a gap in the side portion, the toner floating inside the housing 36 tends to flow out from the gap. The toner thus soaring toward the gap adheres to the LED head array 31.
As shown in FIG.
An elastic body such as 45 is attached. The sponges 45 are formed to have a length substantially equal to the front-back length of the LED head 30, and when the intermediate cover 8 is closed, the LED head 30 is formed.
The lower surface of the housing contacts the sponges 45, 45, and the space inside the housing 36 is separated from the space above the housing 36. As a result, the air flow generated by the rotation of the photoconductor drum 16 does not flow out from the slit 36a, flows substantially in the circumferential direction along the photoconductor drum 16, and is carried in the air flow. Hardly adheres to the LED head array 31.

Alternatively, this sponge 45, 45 is LE
The D head 30 may be attached to the lower surfaces of both side portions, or the sponges 45 may contact the upper surface of the housing 36 when the intermediate cover 8 is closed. Further, the sponge 45 may be provided only on one side (left side) close to the exhaust fan 45. It should be noted that rubber or the like may be attached to the upper surface of the housing 36 or the lower surface of the LED head 30 instead of the foamed material such as the sponges 45, 45, and the elastic material is not particularly limited.

In FIG. 11, instead of the sponges 45, 45, films 46, 46, which are sheet-like members, are hung vertically from the side surface of the LED head 30. The film 46.4
The film 6 is formed to have a length substantially equal to the front-rear length of the LED head 30, and the film 4 is formed when the intermediate cover 8 is closed.
The lower end of 6.46 comes into contact with the upper surface of the housing 36 and the slit 3
6a is covered, and the space inside the housing 36 and the space above the housing 36 are divided and separated. As a result, the airflow generated by the rotation of the photoconductor drum 16 is not affected by the slit 36a.
From the outside to the outside, the toner flows in the circumferential direction along the photosensitive drum 16, and the toner carried in the air flow hardly adheres to the LED head array 31.
The film 46 may be provided only on one side (left side) near the exhaust fan 45.

Although some examples according to the present invention have been described above, for example, by combining the examples of FIGS. 5, 7, and 10, the adhesion of toner to the LED head array 31 can be more effectively performed. Can be prevented. in this way,
You may combine some of the above embodiments,
The configuration is not particularly limited. As described above, according to the present invention, it is possible to prevent the toner from adhering to the LED head array 31 and prevent the deterioration of the image quality recorded on the paper.

[0043]

Since the present invention is configured as described above, it has the following effects. First, as in claim 1,
In an image forming apparatus including a developing unit, a photoconductor unit, and a fixing unit, in which the writing unit is projected in the photoconductor unit, an airflow is provided between the photoconductor unit and a mounting substrate supporting the writing unit. By providing the blocking means, it is possible to prevent the floating toner from leaking from the developing unit from flowing toward the fixing unit. Therefore,
Writing means (for example, LED
The amount of toner adhering to the head) is reduced, and deterioration of image quality can be prevented.

According to a second aspect, the developing unit,
In an image forming apparatus including a photoconductor unit and a fixing unit, in which the writing unit is projected in the photoconductor unit, by providing an airflow blocking unit in a gap between the photoconductor unit and the writing unit, The airflow generated by the rotation of the photoconductor drum does not flow from the inside to the outside of the photoconductor unit, but flows almost in the tangential direction along the photoconductor drum, thereby floating on the airflow. The generated toner does not flow in a certain direction of the optical writing unit (for example, the LED head), the amount of toner attached to the writing unit is reduced, and deterioration of image quality can be prevented.

According to a third aspect of the present invention, the air flow blocking means according to the first or second aspect is formed of a sealing member including a protrusion and an elastic body that abuts against the protrusion, and the protrusion is formed. One of the piece or the elastic body is provided on the writing means or its mounting substrate,
By providing the other on the side of the photoconductor unit, the developing unit and the fixing unit, or the inside and outside of the photoconductor unit can be reliably separated by a simple configuration in which the elastic body and the projecting piece are combined, Is writing means (eg LED
It can be configured such that it hardly adheres to the head).

Alternatively, as in claim 4, claim 1,
Alternatively, the photoconductor unit according to 2 has at least a photoconductor drum and a casing that supports the drum, and a slit into which a writing unit is inserted is formed in the casing. The writing means can be made to project from the slit into the housing so that toner hardly adheres to the writing means (for example, the LED head). In particular, the adhesion of toner floating above the housing is prevented.

According to a fifth aspect, the developing unit,
In an image forming apparatus including a photoconductor unit and a fixing unit, in which the writing unit is projected in the photoconductor unit, a sheet-like member is vertically provided around the writing unit. The floating toner flowing in the direction can be blocked so that the toner hardly adheres to the optical writing unit.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a facsimile device 1.

FIG. 2 is a perspective view of the facsimile apparatus 1 with an outer cover 7 opened.

FIG. 3 is a side sectional view of the image recording device 4.

FIG. 4 is an image recording device 4 with an intermediate cover 8 opened.
FIG.

FIG. 5 is a side sectional view of the photosensitive unit 15 and the LED head 30.

6 is a side sectional view of the photosensitive unit 15 and the LED head 30. FIG.

7 is a side sectional view of the photosensitive unit 15 and the LED head 30. FIG.

FIG. 8 is a side sectional view of the photosensitive unit 15 and the LED head 30.

FIG. 9 is a side sectional view of the housing 36 and the LED head 30.

10 is a front cross-sectional view of the housing 36 and the LED head 30. FIG.

FIG. 11 is a front sectional view of a housing and an LED head 30.

FIG. 12 is a side sectional view of the photosensitive unit 15 and the LED head 30.

FIG. 13 is a front sectional view of a housing and an LED head 30.

[Explanation of symbols]

1 Facsimile machine 7 Exterior cover 8 Intermediate cover 8a Shield piece 8b Shielding rib 13 process units 15 Photoconductor unit 16 photoconductor drum 22 Fixing unit 30 LED head 31 LED head array 32 Selfoc lens 36 housing 36a slit 37 ribs 38 Sponge 39 Sponge 41 film 42 film 43 films 45 sponge 46 films

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Claims (5)

[Claims] 1. An image forming apparatus comprising a developing unit, a photoconductor unit, and a fixing unit, wherein the writing unit is projected into the photoconductor unit, and an attachment substrate for supporting the photoconductor unit and the writing unit. An image forming apparatus characterized in that an air flow blocking means is provided between the image forming apparatus and the image forming apparatus to prevent an air flow from the developing unit toward the fixing unit. 2. An image forming apparatus comprising a developing unit, a photoconductor unit, and a fixing unit, wherein the writing unit is projected into the photoconductor unit, and an air flow is present in a gap between the photoconductor unit and the writing unit. An image forming apparatus, characterized in that a blocking means is provided to prevent generation of an airflow from the inside of the photoconductor unit to the outside. 3. The airflow blocking means comprises a sealing member composed of a projecting piece and an elastic body that abuts on the projecting piece, and one of the projecting piece and the elastic body is a writing means, or a mounting substrate thereof. 3. The image forming apparatus according to claim 1, wherein the image forming apparatus is provided on the photoconductor unit side, and the other is provided on the photoconductor unit side. 4. The photoconductor unit has at least a photoconductor drum and a casing for supporting the drum, and the casing is formed with a slit into which writing means is inserted. The image forming apparatus according to claim 1 or 2, which is characterized in that. 5. An image forming apparatus comprising a developing unit, a photoconductor unit, and a fixing unit, wherein a writing unit is projected into the photoconductor unit, and a sheet-shaped member is vertically provided around the writing unit. An image forming apparatus characterized by the above.