JP2000010445A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which prevents cleaning failure. SOLUTION: The device is equipped with a cleaning blade 32 for removing residual toner on an intermediate transfer belt 16, which holds a toner image on it, and a swing means 71 for causing the cleaning blade 32 to swing. The swing means 71 causes the cleaning blade 32 to swing consecutively, thereby shaking off the residual toner accumulating on the cleaning blade 32.

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 having a cleaning device capable of moving toward and away from an image carrier.

[0002]

2. Description of the Related Art In an image forming apparatus provided with a cleaning device for removing residual toner remaining on an image carrier,
2. Description of the Related Art There is known an image forming apparatus in which a cleaning device is provided with a cleaning blade so that the cleaning device can be moved toward and away from an image carrier. When performing the cleaning operation, the cleaning blade presses against the image carrier to scrape off the residual toner, and when not performing the cleaning operation, the cleaning blade separates from the image carrier.

[0003]

However, if a large amount of toner or paper dust accumulates on the ridge line of the cleaning blade due to the cleaning operation, the cleaning blade will have a reduced ability to scrape off residual toner, resulting in poor cleaning. Would.

Accordingly, an object of the present invention is to provide an image forming apparatus for preventing a cleaning failure.

[0005]

According to a first aspect of the present invention, there is provided a cleaning member for removing a residual toner on an image carrier for carrying a toner image, and the cleaning member is repeated from the image carrier for a predetermined time. And a oscillating means for separating, wherein the oscillating means oscillates the cleaning member and sieves residual toner accumulated on the cleaning member.

According to the first aspect of the present invention, the oscillating means continuously oscillates the cleaning member, and sieves residual toner, paper dust, etc. of the cleaning member. Since the residual toner, paper dust, and the like of the cleaning member are sieved off, the residual toner, paper dust, and the like are less likely to accumulate on the cleaning member. .

According to a second aspect of the present invention, in the first aspect of the present invention, there is provided a contacting / separating unit for bringing the cleaning member into or out of contact with the image carrier, and a control unit for controlling the driving of the contacting / separating unit. Wherein the oscillating means is provided in the control means, and the oscillating means brings the cleaning member into and out of contact.

According to the second aspect of the present invention, in an image forming apparatus provided with a contacting / separating means, for example, a color image forming apparatus using a plurality of color toners, the contacting / separating means is used. Since the cleaning member is swung at a time different from the separating operation, it is not necessary to add a new part, and the number of parts is small.

According to a third aspect of the present invention, in the second aspect of the present invention, after the contacting / separating means separates the cleaning member from the image carrier, the swinging means comprises:
The cleaning member is oscillated continuously.

According to the third aspect of the present invention, since the oscillating means continuously oscillates while the cleaning member is separated from the image carrier, it is possible to prevent a load from being applied to the image carrier. I do.

[0011] The invention according to claim 4 is the invention according to claims 1 to 3.
The swinging means swings the cleaning member after the cleaning member removes residual toner on the image carrier.

According to the fourth aspect of the present invention, after the cleaning member removes the residual toner, the cleaning member is continuously swung, so that the residual toner of the cleaning member is always sieved off, and the deposit on the cleaning member is removed. Is always difficult to deposit, so that cleaning failure can be further prevented.

[0013] The invention according to claim 5 is the invention according to claims 2 to 4.
In the invention according to any one of the above, the oscillating means, after the elapse of a set time previously input to the control means,
The cleaning member is swung.

According to the fifth aspect of the present invention, since the cleaning member is swung continuously at the set time, the deposits on the cleaning member can be periodically sieved off. Stabilize.

[0015] The invention according to claim 6 is the invention according to claims 2 to 5.
In the invention according to any one of the above, when the control unit determines that the conveyance of the recording medium is abnormal, the swing unit removes the untransferred toner on the image carrier after the conveyance abnormality occurs. After the cleaning member is removed, the cleaning member is swung.

According to the sixth aspect of the present invention, a large amount of untransferred toner adheres to the image carrier after occurrence of a recording medium conveyance error such as a jam. In addition, the toner is easily deposited on the cleaning member. Since the toner on the cleaning member is sieved off at a time when such toner is likely to accumulate, the toner can be sieved off more efficiently.

[0017] The invention according to claim 7 is the invention according to claims 1 to 6.
In the invention according to any one of the above, after a process control of attaching a belt-shaped toner on the image carrier and controlling image forming conditions based on a result of detection of the toner by a toner amount detection unit, The swinging means swings the cleaning means.

According to the present invention, when image forming conditions such as charging, exposure and development are controlled by the process control by the control means, a large amount of toner is left on the image carrier after the process control. Is adhered, and when the cleaning member removes the toner, the toner easily accumulates on the cleaning member. Since the toner on the cleaning member is sieved off at a time when such toner is likely to accumulate, the toner can be sieved off more efficiently.

[0019]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view showing the internal structure of a color printer A (image forming apparatus) configured as a printer. The color printer A includes an image forming main body 2 and an opening / closing body 3 rotatably provided to the image forming main body 2 via a support shaft 39.
It is opened as shown in FIG. A process unit 4 in which a plurality of process elements are integrally assembled is detachably mounted on the image forming main body 2.

In the image forming main body 2, an electric control unit 41 is provided on the left side in FIG. 1, and a fan 42 is disposed above the electric control unit 41. The fan 42 exhausts air from the inside of the image forming apparatus and prevents the temperature inside the apparatus from rising. I do. In addition, a relatively small-sized feeding device 43 is provided on the right side of the opening / closing body 3 in FIG.

As shown in FIG. 1, belt pulleys 6 and 7 rotatably supported by a unit case 5 of a process unit 4 have an endless belt-shaped photosensitive member 8 as a latent image carrier.
Is wrapped around. Below the photoconductor 8, the photoconductor 8
A charging charger 9 for charging is provided, and the charging charger 9 is also supported by the unit case 5. Incidentally, a drum-shaped photosensitive member, a dielectric drum or a dielectric belt may be used as the latent image carrier.

On the other hand, the image forming main body 2 is provided with a laser writing unit 10 as exposure means, a rotary type color developing device 11 and a black developing device 12. The laser writing unit 10 has a laser light source (not shown), and the light from the light source is reflected by a polygon mirror 10B that is driven to rotate by a motor 10A, and f · θ
The light reaches the surface of the photoconductor 8 via the lens 10C and the mirror 10D, and the surface is exposed.

The color developing device 11 includes a yellow developing device 1
1Y, a magenta developing unit 11M and a cyan developing unit 11C are integrally assembled as a unit, and the whole is rotatably supported by the image forming main body 2. In this embodiment, a powdery developer is used as the developer contained in the yellow developing device 11Y, the magenta developing device 11M, the cyan developing device 11C, and the black developing device 12. As the developer, either a two-component developer having a toner and a carrier, a one-component developer having no carrier, or a liquid developer may be used.

During the image forming operation, the belt pulley 7 is rotationally driven by a driving device (not shown),
The photoconductor 8 is driven to rotate in the direction of arrow A. At this time, the surface of the photosensitive member 8 is subjected to a charge removing operation by the charge removing lamp 13, and then the surface of the photosensitive member 8 is uniformly charged by the charging charger 9, and the charged surface is subjected to light modulation emitted from the laser writing unit 10. Exposure is performed by the laser light L, whereby a first electrostatic latent image corresponding to the written information is formed on the surface of the photoconductor 8. For example, as shown in FIG.
When Y is opposed to the surface of the photoconductor 8, the first electrostatic latent image is visualized as a yellow toner image by the yellow developing device 11Y, and the black developing device 12 8 Separated from the surface.

On the other hand, the unit case 5 rotatably supports two belt pulleys 14 and 15 arranged apart from each other. An endless intermediate transfer belt 16 as an intermediate transfer member is wound around these belt pulleys 14 and 15, and one of the belt pulleys 14 is driven by a driving device, so that the intermediate transfer belt 16
It is driven to rotate in the direction. The intermediate transfer belt 16 and the photoconductor 8 are in contact with each other at a transfer section 17 which is a transfer area. Intermediate transfer belt 1 in this transfer section 17
The rear end of the transfer brush 6 is in contact with the tip of a transfer brush 18 serving as a transfer unit, and the transfer brush 18 is also supported by the unit case 5. Incidentally, a transfer roller, a transfer blade, a corona discharger or the like may be used as the transfer means.

When the yellow toner image formed on the surface of the photoreceptor 8 reaches the transfer section 17 as described above, a voltage having a polarity opposite to that of the toner is applied to the transfer brush 18, whereby The toner image on the surface is the intermediate transfer belt 1
6 is transferred to the surface.

After transfer of the toner image, residual toner that has not been transferred remains on the surface of the photoconductor 8. The residual toner is supported by the unit case 5, and the leading end of the residual toner is applied to the photoconductor 8. The cleaning blade 19 is pressed and scraped off. The residual toner removed from the surface of the photoreceptor 8 in this way falls into the cleaning case 20 integrated with the unit case 5. Cleaning blade 19 and cleaning case 2
0 constitutes the cleaning device 62 for the photoconductor 8;
The residual toner removed from the photoconductor 8 is discharged out of the cleaning case 20 by the toner conveying screw. Note that a fur brush or the like may be used instead of the cleaning blade 19, or a plurality of cleaning members may be used in combination.

After the surface of the photoconductor 8 is cleaned, the photoconductor 8 is again subjected to the above-described steps to form a second electrostatic latent image. When the second electrostatic latent image passes through the color developing device 11, for example, by the rotation of the color developing device 11,
The magenta toner from the magenta developing device 11M is visualized as a second electrostatic latent image. This magenta toner image is also transferred by being superimposed on the yellow toner image on the surface of the intermediate transfer belt 16 on which the yellow toner image has been previously transferred by the action of the transfer brush 18, and the residual toner is scraped by the cleaning blade 19. Dropped.

After transferring the magenta toner, the cyan toner image from the cyan developing device 11C and the black developing device 12
The black toner image is transferred to the intermediate transfer belt 16 by being superimposed sequentially by the above-described steps, and the intermediate transfer belt 16 obtains a full-color toner image. When forming a black toner image, the black developing device 12 is brought closer to the surface of the photoconductor 8 by the rotation of the cam 40 to execute a predetermined developing operation.

On the other hand, a recording medium 22 made of paper or a plastic sheet is stacked on a paper feed cassette 21 set in the image forming main body 2, and the recording medium 22 is moved one by one by the rotation of a feeding roller 23. Fed in the direction. The fed recording catalyst 22 is transported by a transport roller 24 rotatably supported by the opening / closing body 3 and the unit case 5, respectively.
Are transported by the rotation of registration rollers 25, which are also supported by the opening / closing body 3 and the unit case 5, respectively. Then, the toner is fed to the nip portion between the intermediate transfer belt 16 and the transfer roller 26 at a timing matching with the full-color toner image formed on the surface of the intermediate transfer belt 16. At this time, the full-color toner image on the surface of the intermediate transfer belt 16 is collectively transferred to the surface of the recording medium 22 by a voltage having a polarity opposite to that of the toner applied to the transfer roller 26. In addition, the code | symbol 1 in FIG.
This is a protective member for covering and protecting the intermediate transfer belt 16 which is exposed to the outside and which is not preferably touched.

After leaving the intermediate transfer belt 16, the recording medium 22 onto which the full-color toner image has been transferred passes between a fixing roller 28 and a pressure roller 29 of a fixing device 27 provided in the image forming main body 2. The full color toner image is fixed on the surface of the recording medium 22 by the action of the heat and pressure.
The recording medium 22 that has exited the fixing device 27 is discharged, with the image surface facing downward, to a discharge stack portion 31 at the upper portion of the image forming apparatus main body by a discharge roller pair 30 rotatably supported by the image forming main body 2. Paper.

After the full-color toner image is transferred to the recording medium 22, the residual toner remaining on the intermediate transfer belt 16 is removed by the cleaning device 35 for the intermediate transfer belt 16.

As shown in FIG. 3, the cleaning device 35 has a cleaning blade 32 and is disposed in a cleaning case 33 formed by a part of the unit case 5. At a base end portion 60 of the cleaning blade 32, a release lever 50 (contacting / separating means) supported so as to be swingable with respect to the unit case 5 is fixed.
It is controlled by 0. A pressure spring 69 is disposed at the base end portion 60, and the pressure of the pressure spring 69 causes the cleaning blade 32 to be positioned at a position A indicated by a solid line in FIG. When the cleaning blade 32 is located at the position A, the cleaning blade 32 deflects a predetermined amount and scrapes off residual toner, paper dust, and the like on the intermediate transfer belt 16. The residual toner and paper dust scraped off by the cleaning blade 32 are received by the toner receiver 34 and discharged out of the cleaning case 33 by the toner conveying screw 37.

After the surface of the intermediate transfer belt 16 has been sufficiently cleaned, when the intermediate transfer belt 16 receives the toner image from the photoreceptor 8, the release lever 50 is rotated about the rotation shaft 73 by a driving means (not shown) such as a solenoid. Then, the cleaning blade 32 is moved to the position B shown by the two-dot chain line in FIG.

When the toner image before transfer exists on the intermediate transfer belt 16 as described above, the release lever 50 moves the cleaning blade 32 to the position B by swinging the cleaning blade 32, and the toner image is transferred to the recording medium 22. To remove the residual toner after the transfer, the cleaning blade 32 is moved to the position A.

The control means 70 includes a cleaning blade 32 in addition to the normal residual toner scraping operation described above.
Is provided, and a set time for operating the swinging means 71 is input in advance. In the present embodiment, the timing input to the control means 70 means that after the jam detection by the jam detection means 72,
After the process control of the image forming main body 2 to be described later, after the set number of recording media 22 have been printed, and the like. At these set times, the swing means 71 swings the cleaning blade 32 continuously within a fixed time.

The image forming main body 2 controls (process controls) image forming conditions such as charging, exposure, and development after the power is turned on or after a predetermined number of sheets have been printed. This is because the toner is adhered in a belt shape on the intermediate transfer belt 16 to form a toner adhesion amount detection pattern, and the control unit 70 determines the amount of the attached toner based on the detection result detected by the toner detection unit 52. It controls image forming conditions.

Next, the operation of the present embodiment based on the above-described configuration will be described. When the process control is performed by the control unit 70 after the power is turned on to the image forming main body 2 or after the set number of prints, a large amount of toner adheres to the intermediate transfer belt 16 after the process control is completed. I have.

The cleaning blade 32 is moved to the position A by the release lever 50, and the cleaning blade 32 is pressed against the intermediate transfer belt 32 to scrape off the toner. After the toner has been scraped off, the oscillating means 71 causes the cleaning blade 32 to continuously contact and separate (continuously oscillate) within a certain period of time.
The toner that has accumulated on the ridge line 2 is sieved. The toner accumulated on the ridge line of the cleaning blade 32 is sieved off, and the toner hardly accumulates on the ridge line of the cleaning blade 32, so that cleaning failure can be prevented. Further, since the toner hardly accumulates on the ridge line of the cleaning blade 32, the toner can be scraped off over the entire width of the intermediate transfer belt 16.
The cleaning property becomes good.

In the image forming main body 2, when the jam detecting means 72 detects the jam, the control means 70 stops the operation of the apparatus once and opens the opening / closing body 3 to remove the jammed paper as shown in FIG. . When the opening / closing member 3 is closed, the cleaning blade 32 is moved to the position A by the release lever 50 to scrape off the untransferred toner on the intermediate transfer belt 16. After the toner has been scraped off, the cleaning blade 32 is continuously rocked by the rocking means 71 to sift the toner on the ridge line.

After the process control or after the occurrence of a jam, a large amount of toner adheres to the intermediate transfer belt 16, and when the toner is scraped off by the cleaning blade 32, the toner easily accumulates on the ridge line. The control means 70 causes the swinging means 71 to swing the cleaning blade 32 continuously at such a time that the toner is likely to accumulate, so that the toner can be efficiently sieved.

An intermediate transfer belt 1 as an intermediate transfer member
In the color printer A having the transfer roller 6, the intermediate transfer belt 16 rotates many times when the color toner is transferred, so that the cleaning blade 32 performs the contact / separation operation. Since the present invention can be applied to such a cleaning blade 32 as it is, there is no need to add new parts and the like, and the number of parts is small.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention. In the present embodiment, after the process control or the jam, the cleaning blade 32
Are continuously swung. For example, every time the cleaning blade 32 scrapes off the residual toner, or when the recording medium 22
However, it may be performed after reaching a certain number of sheets, for example, every 1000 sheets or every 2000 sheets. Further, the cleaning device 62 for the photoconductor 8 may have the same configuration as the cleaning device 35 for the intermediate transfer belt 16.

Further, in the present embodiment, the cleaning blade 32 is continuously moved toward and away from the intermediate transfer belt 16 by the swinging means 71 (oscillation). The blade 32 may be swung continuously. In this case, application of a load on the intermediate transfer belt 16 by the cleaning blade 32 is prevented.

Further, in the present embodiment, the color printer A using a plurality of color toners is taken as an example, but the same operation and effect can be obtained by applying to a printer, a copying machine, a facsimile or the like using one color toner. Get.

[0046]

According to the first aspect of the present invention, the structure in which the oscillating means continuously oscillates the cleaning member does not reduce the scraping ability of the cleaning member, and prevents defective cleaning.

According to the second aspect of the present invention, the cleaning member is swung at a time different from that of the contact / separation operation by using the contact / separation means, so that it is not necessary to add a new component.
The number of parts is small.

According to the third aspect of the present invention, the swinging means comprises:
Since the cleaning member is continuously oscillated while being separated from the image carrier, it is possible to prevent a load from being applied to the image carrier.

According to the fourth aspect of the present invention, after the cleaning member removes the residual toner, the cleaning member is continuously swung, whereby the cleaning failure can be further prevented.

According to the fifth aspect of the present invention, the cleaning member is swung continuously at the set time, thereby stabilizing the scraping ability of the cleaning member.

According to the sixth aspect of the present invention, the toner on the cleaning member is sieved off after the occurrence of the conveyance abnormality.
Further, the toner can be efficiently removed.

According to the seventh aspect of the present invention, the toner on the cleaning member is sieved after the process control, so that the toner can be sieved more efficiently.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing an internal structure of a color printer A to which the present invention is applied.

FIG. 2 is a configuration diagram showing a state where an opening / closing body is opened.

FIG. 3 is an enlarged sectional view showing the vicinity of a cleaning device.

[Explanation of symbols]

 Reference Signs List 16 Intermediate transfer belt (image carrier) 32 Cleaning blade (cleaning member) 50 Release lever (contact / separation means) 52 Toner amount detection means 70 Control means 71 Swing means A Color printer (image forming apparatus)

Claims (7)

[Claims] 1. A cleaning member for removing residual toner on an image carrier that carries a toner image, and a swing unit that repeatedly separates the cleaning member from the image carrier for a predetermined time, wherein the swing unit includes: An image forming apparatus, wherein the cleaning member is swung to remove residual toner accumulated on the cleaning member. 2. An image forming apparatus comprising: a contacting / separating means for bringing the cleaning member into contact with / separating from the image carrier; and a control means for controlling the driving of the contacting / separating means. The image forming apparatus according to claim 1, wherein the swing unit moves the cleaning member toward and away from the cleaning member. 3. The image forming apparatus according to claim 2, wherein the swinging unit swings the cleaning member continuously after the contacting / separating unit separates the cleaning member from the image carrier. The image forming apparatus as described in the above. 4. The cleaning device according to claim 1, wherein the oscillating unit oscillates the cleaning member after the cleaning member removes residual toner on the image carrier.
The image forming apparatus according to any one of claims 1 to 3. 5. The image according to claim 2, wherein the oscillating unit oscillates the cleaning member after a lapse of a set time input to the control unit in advance. Forming equipment. 6. When the control unit determines that the recording medium is transported abnormally, the swinging unit removes the untransferred toner on the image carrier after the occurrence of the transport abnormality by the cleaning member. The image forming apparatus according to claim 2, wherein the cleaning member is swung. 7. After the process control for attaching a belt-like toner on the image carrier and controlling image forming conditions based on a result of detection of the toner by the toner amount detecting means, the swinging means comprises: The image forming apparatus according to claim 1, wherein the cleaning unit is oscillated.