JPH10123775A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clean a photoreceptor with a transfer material or a cleaning material by causing a relative velocity different from the one in the case of normal printing between each roller related to the carriage of a cut paper as the transfer material and the cleaning material and the photoreceptor or an intermediate transfer body. SOLUTION: A paper feeding roller 20 rotates to feed only one cut paper 23, and feeds it to a carrying roller 18, a resist roller 7, a photoreceptive drum 8, and a fixing device 10. Since the carrying speed of the paper 23 is largely dependent on the circumferential speed of a pressure roller 11, the paper 23 is strongly tensioned in the case of passing through the heating roller and the pressure roller 11 of the device 10, and the carrying speed of the paper 23 is higher than the circumferential speed of the photoreceptive drum 8 when the circumferential speed of the roller 11 is higher than that in the normal printing. Thus, the pressure roller is rotated faster than a normal case by a hand or a signal in the case of need, or periodically rotated fast to enhance the carrying speed of the transfer material (cut paper) 23 so as to clean the photoreceptive drum 8.

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 for forming an image on a photoreceptor and transferring and fixing the image to a transfer material directly or via an intermediate transfer member.

[0002]

2. Description of the Related Art An outline of the operation of an image forming apparatus having a photosensitive member such as an electronic photosensitive drum will be described with reference to FIG.

First, when the CPU 1 receives a print start signal, the main motor 25 is driven by a command from the CPU, and each roller for transporting the cut sheet 23 starts rotating. Turn ON / OFF the paper feed solenoid when ready for drawing
Then, the paper feed roller 20 is rotated, and one sheet of the cut paper 23 is sent to the transport roller 18 by the paper feed roller, and further sent to the registration roller 7. Here, the rotation of the registration roller 7 is started at a timing such that the leading end of the cut sheet 23 and the leading end of the image on the photoconductor 8 coincide. Photoconductor 8
A latent image formed by the laser from the laser drive unit 2 is formed into a toner image by a developing device (not shown), and the toner image is cut at a nip portion between the photoconductor 8 and the transfer roller 9. Transferred to paper 23, and heated roller 1 of fixing device
The toner image is fixed at the nip portion between 0 and the pressure roller 11. Thereafter, the cut sheet 23 on which the image is formed is discharged to the FD discharge unit 17 or the FU discharge unit 16. In such an image forming apparatus, the driving of each roller and the photoconductor for transporting the cut sheet 23 are related to each other, and the peripheral speed of each roller is substantially equal.

[0004]

Problems to be solved in an image forming apparatus having such a photosensitive member include the following.

In an image forming apparatus, a photosensitive member is sensitive to dirt and foreign matter, and in order to form a normal image,
It is necessary to always keep the photoconductor surface clean.

However, a blade or roller for cleaning the photoreceptor cannot completely clean the photoreceptor, and the discharged toner and the solvent of the transfer material are accumulated on the photoreceptor, so that an image cannot be normally formed. The same problem may occur in the intermediate transfer member.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to clean a photosensitive member or an intermediate transfer member in order to solve the above-mentioned problems. The means for cleaning the photosensitive member or the intermediate transfer member will be described below.

According to a first aspect of the present invention, a transfer material is transported by each roller for transporting the transfer material, and an image formed on a photosensitive member or an intermediate transfer member is transferred onto the transfer material by a transfer unit. In an image forming apparatus to be fixed by a fixing device,
Each roller involved in the transfer of the transfer material has a means for varying the speed independently of the photosensitive member or the intermediate transfer member, and the relative speed between the transfer material and the photosensitive member or the intermediate transfer member is And removes the waste toner and the solvent of the transfer material accumulated on the photoreceptor or the intermediate transfer member due to the friction generated in step (1).

A second invention according to the present application is characterized in that a cleaning material is conveyed by a transfer material conveying roller instead of the transfer material.

A third invention according to the present application is characterized in that the means for changing the speed is a speed changing means for changing the transport speed of the transfer material or the cleaning material more than the peripheral speed of the photosensitive member or the intermediate transfer member. And

According to a fourth aspect of the present invention, the speed changing means for changing the conveying speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member includes a pressure roller and a discharge roller which are used during normal printing. It is characterized in that it is a means for rotating faster.

According to a fifth aspect of the present invention, the speed changing means for changing the conveying speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member is provided so that the speed of the photosensitive member or the intermediate transfer member can be increased. Is also a means for speeding up or slowing down. According to a sixth aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photoconductor or the intermediate transfer member includes a pressure roller, a paper discharge roller, and a transfer roller which perform normal printing It is characterized in that it is a means for rotating faster. A seventh invention according to the present application is directed to a seventh aspect of the present invention, wherein the speed changing means for changing the transfer speed of the transfer material or the cleaning material more than the peripheral speed of the photosensitive member or the intermediate transfer member includes a pressure roller, a discharge roller, a transfer roller, a registration roller, and a transfer roller. The roller is a means for rotating the roller faster than during normal printing.

According to an eighth aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material more than the peripheral speed of the photoreceptor or the intermediate transfer material is provided. It is a means for strongly pressing the transfer material or the cleaning material with the paper feed roller and the separation pad or the Duplo roller when passing through the intermediate transfer member and the transfer roller, and applying a load to the conveying force.

According to a ninth aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member may be such that the transfer roller is rotated or the transfer material is changed. Alternatively, when the leading end of the cleaning material passes through the photoconductor or the intermediate transfer member and the transfer roller, the conveyance roller is stopped, and a load is applied to the conveyance force.

According to a tenth aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member is to slow the registration roller and the transfer roller, or When the leading end of the transfer material or the cleaning material passes through the photosensitive member or the intermediate transfer member and the transfer roller, the registration roller and the conveyance roller are stopped, and a load is applied to the conveyance force.

According to an eleventh aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member is provided. Means to stop the transfer of the transfer material or the cleaning material by stopping the driving of the rollers other than the photosensitive member or the intermediate transfer member in a state between the body and the transfer roller, and to drive only the photosensitive member or the intermediate transfer member. Features.

According to a twelfth aspect of the present invention, the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member includes changing a drive gear of the photosensitive member or the intermediate transfer member. Alternatively, a gear switching mechanism or a gear switching mechanism for a driving gear of a transfer roller for transferring the transfer material is provided, and the gear switching mechanism is operated manually or in accordance with a command from a control device.

The difference between the transfer speed of the transfer material or the cleaning material and the peripheral speed of the photosensitive member or the intermediate transfer member is preferably 5% or more.

[0019]

(Embodiment 1) FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus, and FIGS. 2 and 3 show a drive unit of the image forming apparatus. In FIG. 1, 1 is a one-chip microcomputer (CPU) with a built-in ROM, 2 is a laser drive unit, 3 is a scanner motor control unit, 4 is a scanner motor, 5 is a reflection mirror,
6 is a pre-registration sensor, 7 is a registration roller, 8 is a photosensitive drum, 9 is a transfer roller, 10 is a fixing device, 11 is a pressure roller, 12 is a thermistor, 13 is a paper ejection sensor, 14
Is the FU paper discharge roller, 15 is the FD paper discharge roller, and 16 is the FU paper discharge roller.
A paper discharge tray, 17 is an FD paper discharge tray, 18 is a transport roller, 19 is a cassette, 20 is a paper feed roller, 21 is a paper presence / absence sensor, 22 is a paper size detection, 23 is a cut sheet, 24
Denotes a conveyance guide, 25 denotes a drive motor, and 26 denotes a housing of the image forming apparatus.

2 and 3, 101 is a motor pinion gear, 102 is a first W (double) gear, 103 is a second W gear, 104 is a fixing W gear, 105 is a fixing movable gear, and 106 is a fixing clutch. Reference numeral 107 denotes a fixing system oscillating gear, 108 denotes a fixing system oscillating W gear, 109 denotes a fixing system oscillating gear unit, 110 denotes a pressure roller gear, 111 denotes a pressure roller solenoid, 112 denotes an FU drive gear, and 113 denotes a sheet discharge. Gear, 114 is an FD drive gear, 115 is an FD discharge gear,
116 is a feeding system W gear, 117 is a feeding system movable gear, 11
8 is a paper feed system clutch, 119 is a paper feed system swing gear, 120
Is a feed system swing W gear, 121 is a feed system swing gear unit, 122 is a transport drive gear, 123 is a transport roller gear,
124 is a transfer solenoid, 125 is a paper feed clutch, 12
6 is a paper feed roller gear, 127 is a paper feed solenoid, 128
Is a registration roller system movable gear, 129 is a registration roller system clutch, 130 is a registration roller system swing gear, 13
1 is a registration roller system swing W gear, 132 is a registration roller system swing gear unit, 133 is a registration roller gear, 134 is a registration solenoid, 135 is a fixing system spring,
36 is a registration roller system spring, and 137 is a paper supply system spring.

In FIG. 1, a latent image is formed on a photosensitive drum 8 such as an electronic photosensitive drum by a laser emitted from a laser driving unit 2, and the latent image is visualized as a toner image by toner of a developing device (not shown). Is done. On the other hand, only one cut sheet 23 is fed by the rotation of the feed roller 20, and then the cut sheet 23 is fed in the order of the transport roller 18, the registration roller 7, the photosensitive drum 8, and the fixing device 10. Cut paper 2
3 is largely due to the peripheral speed of the pressure roller 11, and if the peripheral speed of the pressure roller 11 is higher than that during normal printing, the cut sheet 23 is pressed against the heating roller of the fixing device 10 by pressure. When the cut paper 23 passes through the roller 11, the cut paper 23 is strongly pulled, and the transport speed of the cut paper 23 is
Faster than the peripheral speed of Although the heating unit of the fixing unit 10 is illustrated as an example of a heating roller, a known heating unit that heats the cut sheet via a heat-resistant film by an elongated heating member may be used.

As a method for making the peripheral speed of the pressure roller 11 higher than that in normal printing, for example, a method using a swing gear unit can be adopted. As shown in FIG. 2, the fixing system movable gear 105 to the fixing system clutch 106, the fixing system swing gear 1
07, fixing system swing W gear 108, pressure roller gear 110
When the drive is transmitted in the normal printing state, the fixing system oscillating gear unit 109 is rotated clockwise as shown in FIG. 3, and the fixing system oscillating gear 107 and the fixing system oscillating W gear 108 are transmitted.
The fixing system clutch 1
06, if the drive is transmitted to the pressure roller gear 110, the speed is not reduced by the fixing system swing W gear 108,
Since the rotation speed of the pressure roller gear 110 is higher than that during normal printing, the peripheral speed of the pressure roller 11 is also higher.

As a method of rotating the fixing system oscillating gear unit 109, for example, a cleaning switch is provided on an exterior part, and the fixing system oscillating gear unit 109 is connected by a lever, and a user manually operates the fixing system oscillating gear unit 109. The cleaning may be performed by rotating. Further, using the conductive fixing system oscillating gear unit 109 and an electromagnetic coil, the electromagnetic coil is operated by a signal from a personal computer, a signal from a cleaning switch provided in a printer, or a signal output from the CPU 1 at a constant cycle. The cleaning may be performed by automatically rotating the fixing-system oscillating gear unit 109 by operating it.

As described above, in the present embodiment, when necessary, the pressure roller is rotated manually or by a signal at a higher speed than normal, or periodically at a higher speed to increase the conveying speed of the cut sheet as the transfer material to increase the photosensitive drum. Can be cleaned. Further, in this example, since the FU discharge gear 113 and the FD discharge gear 115 are interlocked with the pressure roller gear 110, the rotation speed of the rollers 113 and 115 also changes similarly to the pressure roller gear 110, so that the cut sheet 23 is fixed. Paper jam on the downstream side in the transport direction from the container 10 is eliminated.

Note that items that are set to be operated manually or by a signal have the same configuration hereafter, unless otherwise specified in the following embodiments.

(Embodiment 2) Embodiment 2 will be described with reference to FIG. In FIG. 4, reference numeral 201 denotes a fixing idler gear;
Denotes a swing gear, and 203 denotes a sheet discharge idler gear. Other configurations are the same as those in the first embodiment, and a description thereof will be omitted. Embodiment 1
In the second embodiment, the swing gear unit is used as a method for making the peripheral speed of the pressure roller 11 faster than that in normal printing. However, in the second embodiment, the driving unit shown in FIG. The peripheral speed of the pressure roller 11 can be increased by replacing or switching to one with a smaller number of teeth and increasing the number of rotations of the pressure roller 11. At this time, the FU discharge roller 14 and the FD discharge roller 1
5 is released or kept at the same peripheral speed as the pressure roller 11, so that the cut paper 23 does not become jammed behind the fixing device 10. Further, it is preferable to switch the gear 110 so that the gear 202 and the like are rotated and retracted.

(Embodiment 3) In Embodiment 1, the swing gear unit was used as a method for making the peripheral speed of the pressure roller 11 faster than that in normal printing. In Embodiment 3, the fixing unit can be easily replaced. When the user or a service person mounts a cleaning fixing unit having a pressure roller having a larger diameter than usual, the photosensitive drum 8 can be cleaned.

At this time, by replacing the FU discharge roller 14 and the FD discharge roller 15 with those having a large diameter, the cut sheet 23 does not become jammed behind the fixing unit 10.

(Embodiment 4) In this embodiment, FIG.
Reference numeral 6 denotes a drive unit for driving the photosensitive drum 8 and the transfer roller 9. 5 and 6, reference numeral 401 denotes a drum-type movable gear;
2 is a drum system clutch, 403 is a drum system swing gear, 4
04 is a drum system swing W gear, 405 is a drum system swing gear unit, 406 is a photosensitive drum gear, 407 is a drum solenoid, 408 is a transfer system movable gear, 409 is a transfer system clutch, 410 is a transfer system swing gear, 411 Is a transfer system swing W gear, 412 is a transfer system gear unit, 413 is a transfer roller gear, 414 is a transfer solenoid, 415 is a drum system spring, and 416 is a transfer system spring. Other Embodiment 1
The description is omitted because it is the same as.

The transport speed of the cut paper 23 is
8, the resist roller 7 and the pressure roller 11 keep the pressure substantially constant. Therefore, when the rotation speed of the photosensitive drum 8 is increased, the peripheral speed of the photosensitive drum 8 becomes faster than the transport speed of the cut sheet 23.

That is, as shown in FIG.
1 to drum system clutch 402, drum system swing gear 40
3. Drum system swing W gear 404, photosensitive drum gear 406
When the drive is transmitted in the normal printing state, the drum system swing gear unit 405 is rotated clockwise as shown in FIG. 6 so that the drum system swing gear 403 and the drum system swing W gear 404 do not pass through. If the drive is transmitted from the drum-system movable gear 401 to the drum-system clutch 402 and the photosensitive drum gear 406, the rotation speed of the photosensitive-drum gear 406 is higher than that during normal printing because the speed is not reduced by the drum-system swing W gear 404. Therefore, the peripheral speed of the photosensitive drum 8 also increases. The method of rotating the drum-system swing gear unit 405 may be manual or it may be rotated by operating a signal.

The peripheral speed of the photosensitive drum 8 can be increased by replacing the photosensitive drum gear 406 with a gear having a small number of teeth and increasing the rotation speed of the photosensitive drum 8.

(Embodiment 5) In Embodiment 4, the rotational speed of the photosensitive drum 8 is increased to reduce the peripheral speed of the photosensitive drum 8 to the cut sheet 23.
The conveying speed of the cut sheet 23 can be changed to be larger than the peripheral speed of the photosensitive drum 8 by increasing the conveying speed of the photosensitive drum 8 in the fifth embodiment.
By lowering the rotation speed of the photosensitive drum 8 to make the peripheral speed of the photosensitive drum 8 slower than the transport speed of the cut paper 23, the transport speed of the cut paper 23 can be changed more than the peripheral speed of the photosensitive drum 8.

As a method of reducing the number of rotations of the photosensitive drum 8, there is, for example, a method of using a swing gear unit. As shown in FIG. 6, the drum system swing gear 403 and the drum system swing W gear 4
As shown in FIG. 5, the drum system swing gear unit 405 is rotated counterclockwise as shown in FIG. 5 in a state where the drive is transmitted from the drum system movable gear 401 to the drum system clutch 402 and the photosensitive drum gear 406 without passing through the drum system gear 04. When the drive is transmitted from the drum-system movable gear 401 to the drum-system clutch 402, the drum-system swing gear 403, the drum-system swing W gear 404, and the photosensitive drum gear 406, the speed is reduced by the drum-system swing W gear 404. Since the rotation speed of the drum gear 406 is lower than that during normal printing, the peripheral speed of the photosensitive drum 8 is also lower. The method of rotating the drum-system swing gear unit 405 may be manual or it may be rotated by operating a signal.

Further, the peripheral speed of the photosensitive drum 8 can be reduced by replacing the photosensitive drum gear 406 with a gear having a large number of teeth and reducing the rotation speed of the photosensitive drum 8.

(Sixth Embodiment) A sixth embodiment will be described with reference to FIGS. Since FIG. 7 is all the same as FIG. 5, the description is omitted. Since the transport speed of the cut sheet 23 is also greatly affected by the peripheral speed of the transfer roller 9, if the peripheral speed of the transfer roller 9 is higher than that during normal printing, the cut sheet 23 is strongly pulled by the transfer roller 9 and cut. The transport speed of the paper 23 is faster than the peripheral speed of the photosensitive drum 8.

As a method for making the peripheral speed of the transfer roller 9 faster than that in normal printing, for example, there is a method using an oscillating gear unit. Assuming that the drive is transmitted from the transfer system movable gear 408 to the transfer system clutch 409, the transfer system swing gear 410, the transfer system swing W gear 411, and the transfer roller gear 413 as shown in FIG. 7, the transfer system oscillating gear unit 412 is rotated in the counterclockwise direction so that the transfer system oscillating gear 410 and the transfer system oscillating W gear 411 do not pass through the transfer system movable gear 408 to the transfer system clutch 40.
9. When the drive is transmitted to the transfer roller gear 413, the transfer roller gear 41 is not decelerated by the transfer system swing W gear 411.
Since the rotation speed of the transfer roller 3 is higher than that in the normal printing, the peripheral speed of the transfer roller 9 is also higher, and the speed can be increased when the leading end of the cut sheet passes between the photosensitive drum and the transfer roller.

The method of rotating the transfer system swing gear unit 412 may be manual or it may be rotated by signal operation.

The peripheral speed of the transfer roller 9 can be increased by replacing the transfer roller gear 413 with a gear having a smaller number of teeth and increasing the rotation speed of the transfer roller 9.

At this time, the pressure roller 11, the FU discharge gear 113, and the FD discharge gear 115 described in the first embodiment also change the rotation speed in the same manner as the transfer roller gear 413, so that the transfer roller 9 and the fixing device 10 The bending of the cut sheet 23 and the paper jam are eliminated.

(Seventh Embodiment) A seventh embodiment will be described with reference to FIGS. FIG. 8 shows a drive unit of the transport roller 18 and the registration roller 7 extracted from FIG. In the sixth embodiment, the peripheral speed of the transfer roller 9 is increased, so that the transport speed of the cut sheet 23 is increased when the leading end of the cut sheet 23 passes between the photosensitive drum 8 and the transfer roller 9. In this case, the transport speed of the cut sheet 23 can always be made higher than the peripheral speed of the photosensitive drum 8 by increasing the peripheral speed of the transport roller 18 and the registration roller 7 in the same manner as the transfer roller 9.

A method of making the peripheral speed of the pressure roller 8 and the transfer roller 9 faster than that in the normal printing is omitted because the same mechanism as in the above-described first, second, third and sixth embodiments is used.

When the peripheral speed of the conveying roller 18 is set to be higher than that in normal printing, as shown in FIG.
If the drive is transmitted from the feed system clutch 118, the feed system swing gear 119, the feed system swing W gear 120, the transport drive gear 122, and the transport roller gear 123 to the normal print state, as shown in FIG. Paper-based oscillating gear unit 121
Is rotated in the clockwise direction, and from the paper supply system movable gear 117 to the paper supply system clutch 118, the conveyance drive gear 122, and the conveyance roller gear 123 without passing through the paper supply system swing gear 119 and the paper supply system swing W gear 120. When the drive is transmitted, the speed of the conveyance roller gear 123 is not reduced by the sheet feeding system swing W gear 120 and the rotation speed of the conveyance roller gear 123 is higher than that in the normal printing, so that the peripheral speed of the conveyance roller 18 is also higher.

As the method of rotating the sheet feeding system swing gear unit 121, a manual method may be used, or a conductive sheet feeding system swing gear unit 121 and an electromagnetic coil may be used. By turning on / off, the paper feeding system swing gear unit 121 can also be rotated.

The peripheral speed of the transport roller 18 can be reduced by replacing the transport roller gear 123 with a gear having a smaller number of teeth and increasing the rotation speed of the transport roller 18.

Next, when the peripheral speed of the registration roller 7 is set to be higher than that in normal printing, as shown in FIG.
9, if the drive is transmitted to the registration roller system swing gear 130, the registration roller system swing W gear 131, and the registration roller gear 133 in a normal printing state, the registration roller system swing gear unit 132 is clocked as shown in FIG. To move the registration roller system swing gear 130 and the registration roller system swing W gear 131 from the registration roller system movable gear 128 to the registration roller system clutch 12.
9. The drive is transmitted to the registration roller gear 133, and the rotation speed of the registration roller gear 133 is not reduced by the registration roller system swing W gear 131, and the rotation speed of the registration roller gear 133 is higher than that in the normal printing. Become.

Registration roller system swing gear unit 132
Can be rotated manually or by operating a signal.

Further, the peripheral speed of the registration roller 7 can be increased by replacing the registration roller gear 133 with a gear having a small number of teeth and increasing the rotation speed of the registration roller 7.

Embodiment 8 Embodiment 8 will be described with reference to FIG. FIG. 9 is a diagram showing the sheet feeding unit in FIG.
Further, the same reference numerals are the same as those described above, and the description is omitted.

In FIG. 9, in the normal printing state, the sheet feeding roller gear 126 rotated by the sheet feeding clutch 125 is turned on in synchronization with the sheet feeding signal of the sheet feeding solenoid 127 (that is, the notch of the gear). (By detaching from the part 126-1), the paper feed roller 20 makes one rotation, and after one rotation, the OFF operation of the paper supply solenoid (that is, by contacting the notch part 126-1 of the gear). Stop.

During this time, the half-moon-shaped paper feed roller makes one rotation, separates the paper from the cassette, feeds the paper, and delivers it to the transport roller.

In such a configuration, in the present embodiment, the above-described paper feeding is performed, and the ON operation signal is transmitted from the CPU or the like to the paper feeding solenoid 127 again by measuring the time during which the transfer paper passes through the transfer unit. I do. As a result, the paper feed roller gear 126 rotates, but the OF solenoid is immediately supplied to the paper feed solenoid 127.
When the F signal is input, the sheet feeding solenoid 127 contacts the notch 126-2 of the gear. That is, the paper feed roller 20 stands by in a half-rotated or partially-rotated state, running back tension on the transfer paper in progress, and a speed difference occurs between the transfer paper and the photosensitive drum. In order to apply tension to the transfer material by the paper feed roller, it is preferable that the transfer material or the cleaning material is sandwiched between the paper feed roller and the separation pad or the Duplo roller.

After a lapse of approximately the passing time of the target transfer section, the operation of the sheet feeding solenoid causes the sheet feeding solenoid 12 to operate.
7 is a notch 126-1 which is a home position of the gear.
To return to the normal state.

This embodiment can also be used in combination with a later-described embodiment for stopping the registration roller to completely stop the transfer paper and to further exert this effect.

(Embodiment 9) Embodiment 9 will be described with reference to FIGS. FIGS. 10 and 11 show the drive unit of the transport roller 18 extracted from FIG. Cut paper 2
The transport speed 3 is maintained substantially constant by the transport roller 18, the registration roller 7, the transfer roller 9, and the pressure roller 11. In the ninth embodiment, the cut sheet 23 is
The rotation of the transport roller 18 is stopped in contact with both the photosensitive drum 8 and the photosensitive drum 8, and a load is applied to the transport force of the cut paper 23, so that the transport speed of the cut paper 23 is reduced and the peripheral speed of the photosensitive drum 8 is reduced. Make a bigger change.

As a method for stopping the rotation of the transport roller 18, there is, for example, a method using a clutch and a solenoid.
Assuming that the drive is transmitted from the paper feed system movable gear 117 shown in FIG. 10 to the paper feed system clutch 118, the transport drive gear 122, and the transport roller gear 123 in a normal print state, the transport solenoid 124 is moved as shown in FIG. By operating clockwise, the conveying roller gear 123 is stopped. At this time, the rotational force is cut off by the paper feed system clutch 118.

(Tenth Embodiment) A tenth embodiment will be described with reference to FIGS. FIGS. 10 and 12 show the drive unit of the transport roller 18 extracted from FIG. The transport speed of the cut sheet 23 is kept substantially constant by the transport roller 18, the registration roller 7, the transfer roller 9, and the pressure roller 11, but in Embodiment 10, the rotation speed of the transport roller 18 is reduced to By applying a load to the conveying force, the conveying speed of the cut sheet 23 can be changed more than the peripheral speed of the photosensitive drum 8. As a method of reducing the number of rotations of the transport roller 18, for example, a swing gear unit is used.
Assuming that the drive is transmitted from the paper feed system movable gear 117 to the paper feed system clutch 118 and the transport drive gear 122 shown in FIG. 10 in a normal printing state, as shown in FIG. Is rotated in the counterclockwise direction, and when the drive is transmitted from the feed system movable gear 117 to the feed system clutch 118, the feed system swing gear 119, the feed system swing W gear 120, and the transport drive gear 122, The speed is reduced by the paper-based swing W gear 120, and the rotation speed is lower than in the normal printing, and the peripheral speed of the transport roller 18 is also lower. Feeding system swing gear unit 1
As a method of rotating 21, the rotation may be performed manually or by operating a signal. Further, the transfer roller gear 123 is replaced with a gear having a large number of teeth, and
Peripheral speed can be reduced.

(Embodiment 11) Embodiment 11 will be described with reference to FIGS. FIGS. 13, 14, and 15 show the drive unit of the registration roller 7 extracted from FIG. Since the transport speed of the cut paper 23 is kept substantially constant by the transport roller 18, the registration roller 7, the transfer roller 9 and the pressure roller 11, when the registration roller 7 is stopped or decelerated, the transport force of the cut paper 23 is increased. The transport speed of the cut sheet 23 can be changed more than the peripheral speed of the photosensitive drum 8.

As a method for stopping the rotation of the registration roller 7, for example, there is a method using a clutch and a solenoid. Assuming that the drive is transmitted from the registration roller system movable gear 128 to the registration roller system clutch 129 and the registration roller gear 133 shown in FIG. 13 in a normal printing state, the registration solenoid 134 is operated clockwise as shown in FIG. 133 is stopped. At this time,
The rotational force is cut off by the registration roller system clutch 129. At this time, by stopping the rotation of the transport roller 18 in combination with the ninth embodiment, paper jam after passing the transport roller 18 is eliminated.

Next, as a method of reducing the number of revolutions of the registration roller 7, there is a method of using a swing gear unit, for example.
As described above, assuming that the drive is transmitted in the normal printing state as shown in FIG. 13, the registration roller system swing gear unit 132 is rotated counterclockwise as shown in FIG.
When the drive is transmitted from the registration roller system movable gear 128 to the registration roller system clutch 129, the registration roller system swing gear 130, the registration roller system swing W gear 131, and the registration roller gear 133, normal printing is performed by adding the registration roller system swing W gear 131. The rotation speed is lower than at the time, and the peripheral speed of the registration roller 7 is also lower. The method of rotating the registration roller system swing gear unit 132 may be manual,
It can also be rotated by operating a signal. Further, by replacing the registration roller gear 133 with a gear having a large number of teeth, the number of rotations of the registration roller 7 is reduced, so that the registration roller 7
Peripheral speed can be reduced. Further, at this time, by changing the rotation speed of the transport roller 18 in combination with the tenth embodiment, a paper jam after the transport roller 18 has passed is eliminated.

(Twelfth Embodiment) A twelfth embodiment will be described with reference to FIGS. In this embodiment, by rotating only the photosensitive drum and stopping the other drive systems, a speed difference is generated between the photosensitive drum and the transfer material, thereby achieving the object.

In FIG. 2, the transfer material is conveyed in a normal printing operation, and at a predetermined position, that is, when the leading end of the transfer material has passed the photosensitive drum, the paper feed roller gear 126 is stopped by the paper feed solenoid 127. Holding and feeding roller 20
Put in a non-rotating state.

The conveying roller 18 stops the conveying roller gear 123 by the conveying solenoid 124, and the registration roller 7 stops the registration roller gear 133 by the registration solenoid 134 in the same manner as before. Further, the transfer roller 9 uses a transfer solenoid 414 to transfer the transfer roller gear 431 to the pressure roller 11 and the subsequent FU discharge rollers 14, FD.
The discharge roller 15 stops the pressing roller gear 110 by the pressing roller solenoid 111.

As described above, the transfer material stops between the photosensitive drum and the transfer roller, and only the photosensitive drum rotates, so that the purpose of cleaning can be achieved.

The effect is further obtained by alternately switching the sequence of transporting the transfer material and the above sequence to change the position of the transfer material little by little, stopping the transport system, and rotating the photosensitive drum. I can do it. In this case, the amount of light applied to the photosensitive drum, the developing conditions, and the transfer conditions are set to meet the purpose of cleaning.

(Embodiment 13) The above embodiment is an example in which an image formed on a photosensitive drum is directly transferred to a transfer material, but an image formed on a photosensitive drum is temporarily transferred to an intermediate transfer member. Then, an embodiment of an image forming apparatus that transfers an image on the intermediate transfer member onto a transfer material will be described with reference to FIGS. 16 and 17. In FIG.
Reference numeral 501 denotes an intermediate transfer member onto which an image on the photosensitive drum 8 is transferred. In FIG. 17, reference numeral 502 denotes a drive gear of the intermediate transfer member. Other configurations are the same as those of any of the first to twelfth embodiments, and thus detailed description is omitted. With such a configuration, the intermediate transfer body is cleaned in the image forming apparatus having the intermediate transfer body, similarly to the case where the photosensitive drum is cleaned in Embodiments 1 to 12 described above.

In the above embodiment, an example has been described in which cut paper is used as a transfer material for cleaning a photosensitive drum or an intermediate transfer member. However, the present invention is suitable for cleaning a thin cloth member or the like instead. The member may be transported to the photosensitive drum unit for cleaning.

[0068]

As described above, according to the present invention,
A relative speed different from that during normal printing is generated between each photoreceptor or intermediate transfer body and each roller involved in the transfer of cut paper or cleaning material as a transfer material. It can be cleaned cleanly, does not require a unique mechanism for cleaning, and is simple in construction.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus using electrophotography according to the present invention.

FIG. 2 is a schematic configuration diagram of a drive gear of an example of the image forming apparatus according to the present invention.

FIG. 3 is a schematic configuration diagram of a fixing system and a sheet discharging system gear of an example of the image forming apparatus according to the present invention.

FIG. 4 is a schematic configuration diagram of a fixing system and a sheet discharging system gear of an example of the image forming apparatus according to the present invention.

FIG. 5 is a schematic configuration diagram of a drum system and a transfer system gear of an example of the image forming apparatus according to the present invention.

FIG. 6 is a schematic configuration diagram of a drum system and a transfer system gear of an example of the image forming apparatus according to the invention.

FIG. 7 is a schematic configuration diagram of a drum system and a transfer system gear of an example of the image forming apparatus according to the invention.

FIG. 8 is a schematic configuration diagram of a sheet feeding and conveying system and a registration roller system gear of an example of the image forming apparatus according to the present invention.

FIG. 9 is a schematic configuration diagram of a sheet feeding unit of an example of the image forming apparatus according to the invention.

FIG. 10 is a schematic configuration diagram of a sheet feeding and conveying system gear of an example of the image forming apparatus according to the present invention.

FIG. 11 is a schematic configuration diagram of a sheet feeding and conveying system gear of an example of the image forming apparatus according to the present invention.

FIG. 12 is a schematic configuration diagram of a sheet feeding and conveying system gear of an example of the image forming apparatus according to the present invention.

FIG. 13 is a schematic configuration diagram of a sheet feed / transport system and a registration roller system gear of an example of the image forming apparatus according to the present invention.

FIG. 14 is a schematic configuration diagram of a sheet feeding and conveying system and a registration roller system gear of an example of the image forming apparatus according to the invention.

FIG. 15 is a schematic configuration diagram of a sheet feeding and conveying system and a registration roller system gear of an example of the image forming apparatus according to the invention.

FIG. 16 is a schematic configuration diagram of an example of an image forming apparatus having an intermediate transfer member according to the present invention.

FIG. 17 is a schematic configuration diagram of an intermediate transfer system gear as an example of the image forming apparatus according to the invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... CPU 2 ... Laser drive part 7 ... Registration roller 8 ... Photosensitive drum 9 ... Transfer roller 10 ... Fixing device 11 ... Pressure roller 12 ... Thermistor 14, 15 ... Discharge roller 104, 105
... Fixing system gear 110 ... Pressurizing roller gear 112,113
... Paper discharge gears 116 and 117... Paper feed system gear 123... Conveyance roller gear 126.

Claims (12)

[Claims] An image formed on a photosensitive member or an intermediate transfer member is transported by a transfer material transporting roller.
In an image forming apparatus in which transfer is performed on a transfer material by a transfer unit and is fixed by a fixing device, each roller related to the transfer of the transfer material has a unit that can independently vary a speed with respect to the photoconductor or the intermediate transfer body. An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein
An image forming apparatus wherein a cleaning material is conveyed by a transfer material conveying roller instead of a transfer material. 3. The image forming apparatus according to claim 1, wherein said means for changing the speed changes the conveying speed of the transfer material or the cleaning material more than the peripheral speed of the photosensitive member or the intermediate transfer member. An image forming apparatus, characterized in that: 4. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be greater than the peripheral speed of the photosensitive member or the intermediate transfer member includes a pressing roller and a discharge roller. An image forming apparatus characterized in that it is means for rotating faster than during normal printing. 5. The image forming apparatus according to claim 3, wherein the speed changing means for changing the conveying speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member normally moves the photosensitive member or the intermediate transfer member. An image forming apparatus, which is means for rotating faster or slower than during printing. 6. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photoconductor or the intermediate transfer body includes a pressure roller, a paper discharge roller, An image forming apparatus comprising: means for rotating a transfer roller faster than during normal printing. 7. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photoconductor or the intermediate transfer body includes a pressure roller, a paper discharge roller, An image forming apparatus comprising: means for rotating a transfer roller, a registration roller, and a conveyance roller faster than during normal printing. 8. The image forming apparatus according to claim 3, wherein the speed changing means for changing the transport speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member is such that the transfer material or the cleaning material has a leading end. An image forming apparatus comprising: means for strongly pressing a transfer material or a cleaning material with a paper feed roller and a separation pad or a Duplo roller when passing a photoreceptor or an intermediate transfer member and a transfer roller to apply a load to a conveying force. 9. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be greater than the peripheral speed of the photosensitive member or the intermediate transfer member, Alternatively, the image forming apparatus is a unit that stops the transport roller when the leading end of the transfer material or the cleaning material passes through the photoconductor or the intermediate transfer member and the transfer roller, and applies a load to the transport force. 10. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be greater than the peripheral speed of the photosensitive member or the intermediate transfer member delays the registration roller and the transport roller. An image forming apparatus for stopping a registration roller and a conveying roller when a leading end of a transfer material or a cleaning material passes through a photoconductor or an intermediate transfer member and a transfer roller, and applying a load to a conveying force. 11. The image forming apparatus according to claim 3, wherein the speed changing means for changing the transfer speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photosensitive member or the intermediate transfer member is such that the transfer material or the cleaning material is a photosensitive member. Alternatively, by stopping the driving of the rollers other than the photoconductor or the intermediate transfer body in a state between the intermediate transfer body and the transfer roller to stop the conveyance of the transfer material or the cleaning material, and driving only the photoconductor or the intermediate transfer body. An image forming apparatus, comprising: 12. The image forming apparatus according to claim 3, wherein the speed changing unit that changes the transport speed of the transfer material or the cleaning material to be larger than the peripheral speed of the photoconductor or the intermediate transfer body is a photoconductor or an image forming apparatus. It has a mechanism for changing or switching the drive gear of the intermediate transfer body, or a mechanism for switching the drive gear of the transfer roller of the transfer material, and operating the gear switch mechanism manually or by a command from a control device. Image forming apparatus.