JP2003295713A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus forming air ducts by an image forming process means and a rail member for supporting the image forming process means, connecting the air ducts to a suction means and ventilation means to eliminate the necessity of additional attachment of a suction duct, ventilation duct or the like and capable of easily constituting the air ducts even when there is no excess space around an image carrier and reducing the number of components. <P>SOLUTION: The image forming apparatus is characterized in that the air ducts 9a, 9b are formed out of the lower surface 3c of a developer 3, the upper surface 8a of the rail member 8 and a projection part 3b formed on the lower surface 3c of the developer 3 and the aperture parts of the air ducts 9a, 9b are arranged in the vicinity of the lower side of an adjacent part between a photosensitive drum 1 and a developing sleeve 3a. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a printer and a facsimile.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic copying machine or the like, toner is blown from a developing sleeve provided in a developing device to a photosensitive drum by using electrostatic force to form a toner image on the photosensitive drum. At this time, a part of the toner that was not used for image formation may not be collected by the developing device and may become scattered toner and stain the inside of the apparatus.

Toner scattering into the apparatus is not only visually unclean, but also may adversely affect the image. For this reason, there are adopted a system in which a suction fan is provided on the inner side of the developing device to absorb the scattered toner, and a system in which a suction duct is provided above and below the developing device around the photosensitive drum to absorb the scattered toner.

[0004]

However, in the above-mentioned conventional example, when the suction fan is arranged on the inner side of the developing device, it is difficult to catch the scattered toner on the front side of the developing device and the suction efficiency is poor. There's a problem.

If a suction duct is provided above or below the developing unit around the photosensitive drum, a space for providing the suction duct around the photosensitive drum is required. Since various image forming process means are arranged around the photosensitive drum, it is general that the component density is very high and there is no room in space.

Particularly, in a model in which the developing device is detached from the photosensitive drum and pulled out in front of the apparatus by itself, a rail member for detachably supporting the developing device is required, so that the developing device is sucked around the photosensitive drum. It is often difficult to arrange both the duct and the rail member in terms of space.

The present invention solves the above-mentioned problems.
The purpose is to form an air passage by an image forming process means and a rail member that supports the image forming process means, and connect the air passage to a suction means or an air blowing means to thereby form a suction duct or an air blowing duct. It is an object of the present invention to provide an image forming apparatus capable of easily forming an air passage and reducing the number of parts even when there is no space around the image carrier without the need to separately install the above.

[0008]

An image forming apparatus according to the present invention for achieving the above-mentioned object is provided for supporting an image forming process means arranged around an image carrier and the image forming process means. A rail member provided in the image forming apparatus main body in parallel with the longitudinal direction of the image carrier, and corresponding to the wall surface of the image forming process unit and the wall surface of the rail member, and these wall surfaces. An air passage is formed by the wall-shaped member provided on the image forming process means side or the rail member side, and the air passage is connected to the suction means or the air blowing means and is on the side facing the image carrier. It is characterized by having an opening.

Since the present invention is configured as described above, the wall surfaces of the image forming process means and the rail member, and the walls provided on the image forming process means side or the rail member side corresponding to these wall surfaces. An air passage can be formed by the shape member. Then, by connecting the air passage to the suction means or the air blowing means and disposing the opening portion on the side facing the image carrier, the air passage is sucked by the suction means and the periphery of the image carrier is carried out from the opening portion. It is possible to suck the scattered toner and the like, or to blow air from the opening portion through the air passage by the air blowing means to raise the temperature and to cool.

Therefore, it is not necessary to separately attach a suction duct or a ventilation duct, and the air passage can be easily constructed even when there is no space around the image carrier.
The number of parts can also be reduced.

Further, the image forming process means is placed and supported on the upper part of the rail member, and the air passage is formed by the lower surface of the image forming process means, the upper surface of the rail member and the wall-like member. A configuration may be employed in which the air passage opening is provided in the vicinity of the lower side of the vicinity of the image forming process means and the image carrier.

Further, the image forming process means is suspended and supported by the rail member provided above the image forming process means, and the upper surface of the image forming process means, the lower surface of the rail member and the wall-like member. The air passage is formed by means of, and the opening of the air passage may be provided in the vicinity of the upper side of the vicinity of the image forming process means and the image carrier.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in the case of being applied to an electrophotographic copying machine as an example of an image forming apparatus according to the present invention will be specifically described with reference to the drawings. 1 is a sectional explanatory view showing a configuration of a first embodiment of an image forming apparatus according to the present invention, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIGS. It is a figure which shows the structure of each sealing means between the wall-shaped member and rail member which were provided in FIG.

First, the configuration of the first embodiment of the image forming apparatus according to the present invention will be described with reference to FIGS. In FIG. 1, reference numeral 1 is a photosensitive drum that serves as an image carrier.
Around the photosensitive drum 1, a primary charging roller 2 serving as a primary charging means for uniformly charging the surface of the photosensitive drum 1,
On the surface of the photosensitive drum 1, an optical unit that irradiates the surface of the uniformly charged photosensitive drum 1 with a laser beam L corresponding to an original image read by an image reading unit (not shown) to form an electrostatic latent image. A developing device 3 serving as a developing unit that supplies toner serving as a developer to the formed electrostatic latent image by the developing sleeve 3a, and a recording sheet supplying unit (not shown)
A transfer roller 5 serving as a transfer unit that is pressed against the photosensitive drum 1 via a recording sheet that is fed by the registration roller pair 4 in synchronization with the rotation of the photosensitive drum 1, and the transfer roller 5
After the toner image formed on the photosensitive drum 1 is transferred to the recording sheet by the action of the above, various image forming process means such as a cleaner container 6 as a cleaning means for removing the residual toner remaining on the photosensitive drum 1. Are arranged.

The photoconductor drum 1 by the pair of registration rollers 4.
The recording sheet conveyed to the nip between the transfer roller 5 and the transfer roller 5 is transferred by the transfer belt 5 after the toner image formed on the photosensitive drum 1 is transferred to the recording sheet by the action of the transfer roller 5. The toner image is conveyed to a fixing unit (not shown), subjected to heating and pressure processing, and the toner image is permanently fixed, and is discharged to the outside of the apparatus.

The developing device 3 which is an image forming process means and a developing means is disposed in parallel with the longitudinal direction (axial direction) of the photosensitive drum 1 which is an image bearing member, and is provided in the main body of the image forming apparatus. The rail member 8 made of an iron plate having a thickness of t = 1.2 mm is placed and supported on the upper portion of the rail member 8, and is fixed to the rail member 8 by screws (not shown).

A projecting portion 3b serving as a wall-shaped member is formed on the bottom of the developing device 3, and the developing device 3 is provided via the projecting portion 3b.
Is mounted on the upper surface of the rail member 8. Then, a space having a height of, for example, about 5 mm is formed between the lower surface 3c, which serves as the wall surface of the developing device 3, and the upper surface 8a, which serves as the wall surface of the rail member 8, by the protrusion 3b.

A lower surface 3c which is a wall surface of the developing device 3, an upper surface 8a which is a wall surface of the rail member 8, and a projection 3 which is a wall-like member provided facing the upper surface 8a of the rail member 8.
As shown in FIG. 2, the gap formed by b and the air passage 9
A suction fan that is formed as a and 9b, and the suction upstream side (upper side in FIG. 2) of the air passages 9a and 9b joins to serve as suction means.
The developing sleeve 3a of the developing device 3 is connected to the suction duct 11 provided with 10, and the opening side is the side facing the photoconductor drum 1 serving as an image carrier and the image forming process means and the developing means. In the vicinity of the lower side of the vicinity of the photosensitive drum 1, the developing sleeve 3a is arranged over substantially the entire length in the longitudinal direction.

The developing container of the developing device 3 of this embodiment is ABS.
(Acrylonitrile-butadiene-styrene copolymer)
The photoconductor drum 1 is made of resin and has an outer diameter of about 30 mm, and the developing sleeve 3a has an outer diameter of about 20 mm.

During image formation, the photosensitive drum 1 rotates in the clockwise direction in FIG. 1, and the developing sleeve 3a rotates in the counterclockwise direction in FIG. 1 at about 1.5 to 2 times the peripheral speed of the photosensitive drum 1. Rotates at the peripheral speed of. Generally, a developing method in which the photosensitive drum 1 and the developing sleeve 3a rotate in the same direction (forward direction) in the proximity portion as shown in FIG. 1 is called a forward developing method.

At the time of development, the toner not transferred to the surface of the photosensitive drum 1 is collected by the developing sleeve 3a in the developing device 3, but a part of the toner which is not collected is separated from the developing sleeve 3a and is developed. It scatters in the area 12 on the lower side of FIG. 1 in the vicinity of the sleeve 3a and the photosensitive drum 1, and drifts as a toner cloud.

When this toner cloud is left as it is, it scatters in the machine due to the air current in the machine, such as a drum wind generated by the rotation of the photosensitive drum 1, and adversely affects the inside of the machine and the image formed on the recording sheet.

Therefore, in this embodiment, the space formed by the left end portion 8b of the rail member 8 shown in FIG. 1 and the lower portion 3d of the developing container of the developing device 3 arranged below the developing sleeve 3a is used as a suction port, and the rail is used. A gap formed by the upper surface 8a of the member 8, the lower surface 3c of the developing device 3, and the wall surface of the protrusion 3b is used as air passages 9a and 9b (ducts), and the suction fan 10 is rotationally driven to suck and remove the toner cloud. You can do it.

As shown in FIG. 2, the suction duct 11 provided with the suction fan 10 is attached to the main body rear side plate 13 provided at the back side of the main body of the image forming apparatus at a position deviated from the outer periphery of the photosensitive drum 1. And ribs 3b1, 3b2, 3b3 that draw a predetermined curve so that the airflow generated by the suction of the suction fan 10 flows uniformly and smoothly in the longitudinal direction of the photosensitive drum 1 from the opening facing the photosensitive drum 1. The shape of the air passages 9a and 9b is realized by the protrusion 3b configured by.

In FIG. 2, 14 is a filter for collecting the scattered toner sucked by the suction fan 10, and 15 is provided between the end of the suction duct 11 and the end of the protrusion 3b. It is a seal member.

3 and 4 are enlarged views showing an example of a contact portion between the lower end portion of the protruding portion 3b such as the ribs 3b1, 3b2, 3b3 provided on the lower surface 3c side of the developing device 3 and the upper surface 8a of the rail member 8. It is a figure. The lower end of the protrusion 3b and the upper surface 8a of the rail member 8
Since a contact portion with the airtightness is required, a sponge member 16 serving as a sealing member is attached to the lower end portion of the protrusion 3b, and the sponge member 16 is further considered in consideration of slidability with the upper surface 8a of the rail member 8.
A PET (polyethylene terephthalate) sheet 17 having a thickness of about 0.1 mm is attached as a sliding member on the surface.

By mounting and fixing the developing device 3 on the upper surface 8a of the rail member 8, the sponge member 16 is crushed by being pressed by the protrusion 3b provided on the lower surface 3c of the developing device 3
The airtightness between the developing device 3 and the rail member 8 is secured through the ET sheet 17 and the upper surface 8a of the rail member 8 with the sponge member 16 interposed therebetween.

In the example shown in FIG. 4, the thickness of the sponge member 16 in the natural state is formed in advance to be larger than the height of the step 3e at the tip of the projection 3b, and the PET sheet 17 is used.
The sponge member 16 is crushed in a state where the step portion 3e is in contact with the upper surface 8a of the rail member 8 via the PET sheet 17 and adheres to the upper surface 8a of the rail member 8 through the PET sheet 17,
Airtightness between the developing device 3 and the rail member 8 is ensured through the interposition of 16.

3 and 4 show an example of the sealing structure of the air passages 9a and 9b formed between the rail member 8 and the developing device 3, the present invention is not limited to these examples. The present invention is not limited to the example, and it is possible to use other various members for ensuring airtightness and other sealing structures.

According to the above structure, the upper surface 8 of the rail member 8
a and the lower surface 3c of the developing device 3 to form an air gap.
a and 9b are configured and used as an air duct to effectively suck and collect the toner cloud generated in the peripheral portion of the vicinity of the photosensitive drum 1 and the developing sleeve 3a in a minimum space. Can be done.

Further, even in a model in which there is a space in the periphery of the photosensitive drum 1, if the above configuration is adopted, it is not necessary to separately prepare an air duct member or the like, and the number of parts can be reduced to reduce the cost. Can be planned.

In this embodiment, since the developing device 3 is made of resin, there is flexibility in molding, and the lower surface 3c of the developing device 3 is provided.
The projections 3b such as the ribs 3b1, 3b2, 3b3 can be easily formed on the side to easily form the air passages 9a, 9b, but the present invention is not limited to these configurations. Instead, the member forming the air passage is the developing device 3 or the rail member 8
It may be formed from either one or both.

Further, although the suction fan 10 is provided on the back side of the main body of the apparatus, the suction fan 10 may be arranged in front of or on the side of the main body of the apparatus to set the air bleeding direction to a desired direction.

Next, the configuration of the second embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. FIG. 5 is a partial cross-sectional explanatory view showing the configuration of the second embodiment of the image forming apparatus according to the present invention. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the second embodiment shown in FIG. 5, when a so-called counter developing system is assumed in which the photosensitive drum 1 and the developing sleeve 3a provided on the developing device 3 rotate in opposite directions (counter direction) in the proximity portion. Is an example.

In FIG. 5, a developing device 3 serving as an image forming process means and a developing means is suspended and supported by a rail member 21 provided above the developing device 3, and the developing device 3 develops. The sleeve 3a rotates clockwise in FIG. At this time, the toner cloud floats in a region 22 formed above the proximity of the photosensitive drum 1 and the developing sleeve 3a.

Therefore, the suction port of the collecting duct needs to be formed above the developing sleeve 3a. Therefore, in this embodiment, the upper surface 3f that is the wall surface of the developing device 3 and the lower surface that is the wall surface of the rail member 21 provided above the developing device 3
An air passage 23a is formed by the respective wall surfaces of 21a, the hanging pieces 21b and 21c of the rail member 21 which is a wall-shaped member formed corresponding to these wall surfaces, and the suspension piece 3g provided in the developing device 3. .

A sponge member 16 is provided as a seal member at the contact portion between the developing device 3 and the rail member 21 on the developing device 3 side as in the first embodiment.
On the surface of 16, a PET sheet is attached as a sliding member (not shown). This ensures the airtightness of the air passage 23a formed by the developing device 3 and the rail member 21.

A penetrating hole 3g1 is formed in the suspension piece 3g of the developing device 3, and an upper surface 3f which is a wall surface of the developing device 3 and a lower surface 21a which is a wall surface of the rail member 21 are communicated with the penetrating hole 3g1. The air passage 23b is formed by the formed void.

The opening of the air passage 23b is located in the vicinity of the upper side of the photosensitive drum 1 serving as an image carrier and the vicinity of the developing sleeve 3a of the developing device 3 serving as image forming process means and developing means. The developing sleeve 3a is formed over substantially the entire length in the longitudinal direction.

As in the first embodiment, a suction fan, a filter, etc., not shown, provided on the back side of the apparatus main body are provided on one side of the air passage 23a, and the developing device is provided on the other side of the air passage 23a. It is sealed by a wall-shaped member (not shown) formed by 3 and a part of the rail member 21. Then, a suction fan (not shown) is rotationally driven to suck air, so that the air passage 23a,
The toner scattered in the area 22 is sucked and collected through 23b.

The other structure is the same as that of the first embodiment, and the same effect can be obtained.

In each of the above embodiments, the air passages 9a, 9b and 23 are provided between the developing device 3 which serves as the developing means as the image forming process means and the rail members 8 and 21 which support the developing device 3.
Although an example of the case where a and 23b are provided to collect the scattered toner has been described, as other image forming process means, a charging means such as a primary charging roller 2 arranged around the photoconductor drum 1 or a photosensitive means. Various image forming process means such as optical means for irradiating the surface of the body drum 1 with the laser beam L to form an electrostatic latent image, transfer means such as the transfer roller 5, cleaning means such as the cleaner container 6, and the like. An air passage may be formed between the rail member and the rail member.

Further, in each of the above-described embodiments, an example in which the air passage is sucked by the suction fan serving as the suction means for the purpose of processing the toner cloud by the scattered toner has been described. It is also possible to raise the temperature and cool it by blowing air from it. Further, it can be applied to ozone treatment generated in the machine.

[0045]

Since the present invention has the above-described structure and operation, an air passage is formed by the image forming process means and the rail member supporting the image forming process means, and the air passage is sucked by the means. It is not necessary to attach a suction duct or a ventilation duct separately by connecting to the air blower or the air blower, and even if there is no space around the image carrier, the air passage can be easily configured and the number of parts can be reduced. .

That is, the wall surface of the image forming process means and / or
Alternatively, the air passage can be formed by the wall surface of the rail member and the wall-shaped member provided on the image forming process means side and / or the rail member side corresponding to these wall surfaces. Then, by connecting the air passage to the suction means or the air blowing means and disposing the opening portion on the side facing the image carrier,
The suction means can suck the air passage to suck the toner or the like scattered around the image carrier from the opening portion, or the air blowing means can blow the air from the opening portion to cool or raise the temperature. .

Therefore, it is not necessary to separately install a suction duct or a ventilation duct, and the air passage can be easily constructed even when there is no space around the image carrier.
The number of parts can also be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory diagram showing a configuration of a first embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a diagram showing a configuration of each sealing unit provided between a wall-shaped member and a rail member, which is provided on the developing unit side serving as an image forming process unit.

FIG. 4 is a diagram showing a configuration of each sealing unit provided between a wall-shaped member and a rail member, which is provided on the developing unit side serving as an image forming process unit.

FIG. 5 is a partial cross-sectional explanatory view showing the configuration of the second embodiment of the image forming apparatus according to the present invention.

[Explanation of symbols]

1 ... Photosensitive drum, 2 ... Primary charging roller, 3 ... Developing device,
3a ... Development sleeve, 3b ... projections, 3b1, 3b2, 3b3 ...
Ribs, 3c ... Lower surface, 3d ... Lower part of developing container, 3e ... Step portion,
3f ... top surface, 3g ... suspension piece, 4 ... registration roller pair, 5
... Transfer roller, 6 ... Cleaner container, 7 ... Conveyor belt, 8
... Rail member, 8a ... Upper surface, 8b ... Left end portion, 9a, 9b
... air passage, 10 ... suction fan, 11 ... suction duct, 12 ... area,
13 ... Rear plate of main body, 14 ... Filter, 15 ... Sealing member, 16 ...
Sponge member, 17 ... PET sheet, 21 ... Rail member, 21
a ... bottom surface, 21b, 21c ... hanging piece, 22 ... area, 23a, 23b
... wind path, L ... laser light

Continued front page    F term (reference) 2H027 JA03 JB13 JB15 JB17 JC06                 2H077 BA08 BA09 CA16 GA04                 2H171 FA02 FA06 FA28 GA03 GA29                       JA06 JA23 JA29 KA09 KA16                       KA22 NA04 NA05 NA06 QA02                       QA08 QA15 QA16 QB03 QB15                       QB32 QB36 QB45 QB46 QB47                       QC03 QC22 QC36 TA08 TA15                       TA17 TA18 UA03 WA01 WA07                       WA23

Claims (3)

[Claims] 1. An image forming process means disposed around an image carrier, and an image forming apparatus main body disposed in parallel with a longitudinal direction of the image carrier to support the image forming process means. And a wall member provided on the side of the image forming process means or on the side of the rail member corresponding to the wall surface of the image forming process means and the wall surface of the rail member. The image forming apparatus is characterized in that an air passage is formed by and the air passage is connected to the suction means or the air blowing means and has an opening on the side facing the image carrier. 2. The image forming process means is placed and supported on an upper portion of the rail member, and the air passage is formed by a lower surface of the image forming process means, an upper surface of the rail member and the wall-shaped member. The image forming apparatus according to claim 1, further comprising an opening of the air passage near a lower side of a vicinity of the image forming process unit and the image carrier. 3. The image forming process means is suspended and supported by the rail member provided above the image forming process means, and the upper surface of the image forming process means, the lower surface of the rail member, and the wall-shaped member. 2. The image forming apparatus according to claim 1, wherein the air passage is formed by means of, and an opening portion of the air passage is provided in the vicinity of an upper side of a proximity portion of the image forming process means and the image carrier.