JP3533016B2 - Electrophotographic equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a laser copying machine, a laser printer, a laser facsimile, etc., in which charging, writing and development are performed, an image is formed on a photoconductor using plural kinds of toner, and the image is formed. The present invention relates to an electrophotographic apparatus that transfers and records on a sheet, and at the same time, removes and collects residual toner on a photoconductor after transfer by a cleaning device.

[0002]

2. Description of the Related Art Generally, in an electrophotographic apparatus using an electrophotographic system, after transfer of an image, about 20% of toner remains on an image carrier without being transferred to a sheet and is removed by a cleaning device. It was collected and discarded as it was.

However, in recent years, from the viewpoint of effective utilization of resources and prevention of environmental damage, it has been required to return the recovered toner to the developing device for recycling.

However, in an electrophotographic apparatus using a plurality of types of toner, for example, a color electrophotographic apparatus such as a so-called functional color or full color having two or more colors, among the recovered toners removed by a cleaning device and recovered. Since toners of different colors are mixed in,
It was difficult to return the collected toner as it is to the developing device for recycling.

Under such circumstances, conventionally, in a two-color color copying machine, latent images having potentials of opposite polarities are formed on a photoconductor, and the latent images are charged with polarities different from each other. After developing with color toners, the two color toners are made to have the same polarity by a pre-transfer charger, and then transferred to paper by a transfer device, and the two color toners remaining on the photoconductor after transfer are the same as before transfer. In some of the toners, the polarity of which has been reversed by a charging device is charged to the original polarity by frictional charging, and then the two color toners are electrically separated and collected and returned to the respective developing devices (Actual Development Sho 58-).
(See Japanese Patent No. 115764).

[0006]

However, in such a conventional two-color color copying machine, since the toner whose polarity is reversed is charged to the original polarity by frictional charging, there is a problem that the structure becomes complicated.

Therefore, an object of the present invention is to make it possible to recycle the recovered toner removed by the cleaning device without complicating the structure in the electrophotographic apparatus using such plural kinds of toner. .

[0008]

Therefore SUMMARY OF THE INVENTION, the invention described in claim 1, performs a static-and writing and development, an image is formed on the photoconductor 20 using a plurality of types of toner, transferring the image While the recording is performed on the paper P, the residual toner on the photoconductor 20 after the transfer is removed and collected by the cleaning device 28, and the mixing ratio of the collected toner is detected.
Based on the detection result of the detection means 35
Determining means 38 for determining the conveying direction of the collected toner,
The collected toner is distributed based on the determination of the determination unit 38 of
In the electrophotographic apparatus including the toner distributing unit 39 ,
The toner sorting means 39 develops the collected toner at the time of normal rotation.
Return to the container side and send it to the waste toner container 41 side at the time of reverse rotation
A rotary transfer means such as a coil spring 46 is provided,
When the rotation / conveyance means is normally rotated, the collected toner is first developed.
First returning means 44 for returning to one developing device such as the container 23
On the other hand, when the rotary conveyance means is reversed,
Is operated and sent to the waste toner container 41 side.
A shutter such as a rotary shutter 54 that shuts off the shutter.
Toner provided by a shutter member and blocked by the shutter member
Second return to return the developer to another developer, such as the second developer 26.
It is characterized in that it comprises a sending means 51 .

According to the first aspect of the invention, when recording is performed, charging, writing and development are performed, an image is formed on the photoconductor 20 using a plurality of types of toner, and the image is transferred. While recording on the paper P, the residual toner on the photoconductor 20 after transfer is removed and collected by the cleaning device 28, and the mixing ratio of the collected toner is detected.
The detection is performed by the means 35, and the rotation is performed based on the detection result of the detection means 35.
The determining means 38 determines the conveying direction of the collected toner, and the determination is made.
The collected toner is sorted by the toner sorting means 39 based on
It At this time, when returning the collected toner to the developing device 1,
The transfer means is normally rotated and the first return means 44 is operated.
Also, when returning to another developing device, the rotary conveyance means is reversed.
And the shutter member is activated, and the toner is sent to the waste toner container side.
The collected toner that has collected is blocked by the shutter member, and the second return
The sending means 51 is operated. On the other hand, if the collected toner is discarded,
The rotary transport means in reverse and operate the shutter member.
Send it to the waste toner container.

[0010] The invention according to claim 2, in the electrophotographic apparatus according to 請 Motomeko 1, the count unit 36 for counting the types apart from the number the dot of toner when performing dot-like writing, from the count value The detection unit 35 is configured with a calculation unit 37 that calculates the mixing ratio.

According to the second aspect of the invention, when the dot-shaped writing is performed, the number of dots is counted by the counting unit 36 according to the type of toner, and the calculation unit 37 calculates from the counted value to collect the dots. The detection unit 35 detects the mixing ratio of the toner thus obtained.

According to a third aspect of the present invention, in the electrophotographic apparatus according to the first aspect, a count unit that counts the exposure time for each type of toner when writing is performed, and the mixing ratio is calculated from the count value. And a calculating section for configuring the detecting means 35.

According to the third aspect of the present invention, when writing is performed, the exposure time for each type of toner is counted by the counting unit, and the calculation unit calculates from the count value to collect the collected toner. The mixing ratio is detected by the detecting means 35.

[0014] According to a fourth aspect of the invention, in the electrophotographic apparatus according to claim 1, in the determination unit 38, the conveying direction by adding a different recovery kinds of toners on a detection result of said detecting means 35 Is determined.

Further, in the invention described in claim 4 , when the determination means 38 makes the determination, the detection result of the detection means 35 takes the recovery rate for each type of toner into consideration.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a schematic configuration of the entire internal mechanism of a two- color color copying machine.

In this two-color color copying machine, a color scanner 10 is provided above the copying machine main body 11.

The color scanner 10 is provided with a contact glass 12 on its upper surface, and a light source 13, a mirror 14,
15 and 16, an imaging lens 17, a color CCD 18 and the like are provided.

The copying machine main body 11 is provided with a drum-shaped photosensitive member 20 in the substantially center thereof. Around the photoconductor 20, a first charging roller 21, a first optical writing device 22, a first developing device 23 for black toner, and a second charging device 2 in a driving direction shown by an arrow.
4, second optical writing device 25, second developing device 26 for red toner,
A transfer roller 27 and a cleaning device 28 are provided.

By the way, the first optical writer 22 and the second optical writer 22
The optical writer 25 includes a semiconductor laser, an LED, a liquid crystal optical shutter, or the like.

When performing color recording using this two-color color copying machine, the document cover (not shown) is opened, a color document is placed on the contact glass 12 and set, and the start button is pressed.

Then, the light from the light source 13 is applied to the color original through the contact glass 12, and the reflected light is sequentially reflected by the plurality of mirrors 14, 15 and 16 to form the imaging lens 1.
It is put in the color CCD 18 through 7. Then, the image information on the manuscript is read, the image information is converted into an electric image signal, and the image signal is subjected to color conversion processing to obtain color image data.

On the other hand, the photosensitive member 20 is rotationally driven in the clockwise direction indicated by the arrow, at which time the surface is uniformly charged by the first charging roller 21, and the first optical writing is performed on the surface based on the color image data. Dot-shaped optical writing is performed by the device 22 to form an electrostatic latent image. Then, when passing through the position of the first developing device 23, black toner is attached to make the electrostatic latent image visible.

Subsequently, the surface of the photoconductor 20 is uniformly charged again by the second charger 24, and dot-shaped optical writing is performed on the surface by the second optical writer 25 based on the color image data. Form an electrostatic latent image. And the second
When passing through the position of the developing device 26, red toner is attached to make the electrostatic latent image visible.

Then, the two color visible images formed on the photoconductor 20 are transferred by the transfer roller 27 onto the upper surface of the paper P conveyed to the lower side of the photoconductor 20.

After the transfer, the paper P is separated and the fixing device 29
Then, the transfer image is fixed there, and then the sheet is discharged to the outside by the sheet discharge roller pair 30.

On the other hand, after the image transfer, the residual toner on the photoconductor 20 is removed and collected by the cleaning blade 28 by the cleaning blade 33.

After that, the photoconductor 20 is neutralized by a static eliminator (not shown) in preparation for another optical writing.

In the case of a monochrome one-color original, for example, a black image original, the second charger 24, the second optical writing device 25, the second developing device 26, etc. are not operated.

By the way, the two-color color copying machine shown in FIG.
As shown in FIG. 1, a detection unit 35 for detecting the mixing ratio of the black toner and the red toner used during the development is provided.

The calculated detection means 35 of this, for calculating a count section 36 for counting the color separate number the dot when performing dot-like writing as illustrated, the mixing ratio of the black toner and red toner from the count value And the part 37.

As shown in FIG. 1, the two-color color copying machine shown in FIG. 1 determines the determining means 38 for determining the conveying direction of the collected toner based on the detection result of the detecting means 35, and the determining means 38. Toner sorting means 3 driven based on
9 is provided.

The calculating section 37 of the detecting means 35 is electrically connected to the judging means 38, and the toner distributing means 39 is connected to the judging means 38 and is provided in the cleaning device 28.

The container case 40 of the cleaning device 28
Has a box shape horizontally long in the axial direction of the photoconductor 20, and as shown in FIG. 2, the toner return port 40 is provided at one side in the longitudinal direction.
A is provided laterally in the drawing, and the toner discharge port 40b is provided downward on the other side.

The toner discharge port 40 of the container case 40
b, the waste toner container 41 is attached via the connecting pipe 45, and the black toner return pipe 4 is connected to the toner return port 40a.
2 is attached at one end.

The other end of the black toner returning pipe 42 is attached to the first developing device 23 as shown in FIGS. Then, the inside of the first developing device 23, the inside of the black toner return pipe 42 and the inside of the container case 40 are communicated with each other, and
An auger 43 rotated by a motor (not shown) is housed in the black toner return pipe 42. Then, the black toner returning pipe 42 and the auger 43 constitute a first returning means 44 for returning the collected toner to the first developing device 23.

On the other hand, inside the container case 40, as shown in FIG. 2, a coil spring 46 which is a rotary transfer means is provided. The coil spring 46 has one end inserted in the toner return port 40a and the other end attached to one end of the rotary shaft 47 across the toner discharge port 40b.

The rotary shaft 47 is rotatably provided by being supported by the container case 40, penetrates the container case 40 and projects the other end to the outside, and has a gear 48 attached thereto. The gear 48 transmits forward / reverse rotation from a drive motor (not shown) through engagement with a drive gear 49 on the drive shaft 50.

The above-mentioned coil spring 46, rotating shaft 47, gear 48, drive gear 49, drive shaft 50, etc. constitute the toner distributing means 39.

Therefore, when performing color recording, as shown in FIG. 1, the number of dots of black toner and red toner used during development is counted by the counting unit 36, and the counted value is input to the calculation unit 37. The calculator 37 calculates the mixing ratio of the black toner and the red toner. That is, for example, if the number of dots of black toner is 1 million and the number of dots of red toner is 100,000, the ratio of the two types of toner is 10: 1, so mixing of red toner The rate is calculated to be 10%.

Then, based on the detection result of the detecting means 35, the judging means 38 determines the conveying direction of the collected toner. In this case, when the mixing ratio of the black toner and the red toner is 1: 1, that is, when the ratio of the red toner to the black toner is 1 as the content of the recovered toner, the range can be said to be sufficiently black. Therefore, for example, when the ratio of the red toner to the black toner is less than 1 as the content of the collected toner, the determination means 38 determines to return to the first developing device 23. For example, when the ratio of the red toner to the black toner is 5, Since it is not in the black range, the determining unit 38 determines to discard it.

When the judgment means 38 decides to return the collected toner, the toner distribution means 39 is operated to rotate the coil spring 46 in the forward direction, and the collected toner is conveyed to the right side in FIG.

Then, the collected toner is put into the black toner returning pipe 42 through the toner returning port 40a, returned to the first developing device 23 through the inside of the black toner returning pipe 42 by the rotation of the auger 43, and is recycled.

On the other hand, when the judgment means 38 decides to discard the collected toner, the coil spring 46 is reversed to convey the collected toner to the left side in FIG. 2, and the toner discharge port 40b.
Through the waste toner container 41.

When calculating the mixing ratio of the black toner and the red toner by the calculating section 37 as described above, the judging means 38 is used.
You should delay the decision of. By doing so, for example, even if the ratio of the red toner to the black toner is 5 as the content of the collected toner at a certain point, the ratio can be monitored until it becomes less than 1 without immediately discarding the collected toner. . When the number becomes less than 1, the determining unit 38 determines the transport direction, so that the amount of collected toner to be discarded can be reduced.

When the coil spring 46 is switched from the reverse rotation to the normal rotation based on the determination of the judgment means 38, the coil spring 46 may be reversely rotated for a predetermined time and then switched to the normal rotation. By doing so, the collected toner can be sufficiently sent to the waste toner container 41 side and then returned, and the collected toner to be discarded can be prevented from entering the first developing device 23.

Further, in the case shown in FIGS. 1 to 3, the detecting means 35 includes a counting section 36 for counting the number of dots for each color, and a calculating section for calculating the mixing ratio of black toner and red toner from the counted value. 37 and 37. However, rather limited thereto, the detection means, although not shown, in a count unit for counting a different exposure time color when writing, a calculating unit for calculating the mixture ratio from the count value You may comprise .

By the way, for example, the first developing device 23 and the second developing device 23
The transfer rate differs depending on the toner used in the developing device 26. FIG. 4 is a graph showing the relationship between the number of dots for each color and the amount of collected toner, with the horizontal axis representing the number of dots and the vertical axis representing the amount of collected toner. As can be seen from this figure, since the amount of toner collected by the first developing device 23 and the amount of toner collected by the second developing device 26 are different, the mixing ratio of the collected toner estimated from the count value of the number of dots is estimated. And the actual mixing ratio may be different. Further, for example, the background stain differs due to the difference in the developing method between the first developing device 23 and the second developing device 26. FIG. 5 is a graph showing the relationship between the number of dots for each color and the amount of collected toner, with the horizontal axis representing the number of dots and the vertical axis representing the amount of collected toner. As can be seen from this figure, since the amount of toner collected by the first developing device 23 and the amount of toner collected by the second developing device 26 are different, the mixing ratio of the collected toner estimated from the count value of the number of dots is estimated. And the actual mixing ratio may be different.

For this reason, if the determination means 38 makes the determination based on the detection result of the detection means 35, the mixing ratio of the collected toner may be incorrect.

[0050] there, in judgment unit 38 may be configured to determine the conveying direction of the collected toner in consideration of the color-specific recovery of the detection result of the detection means 35. By doing so, the mixing ratio of the collected toner can be accurately calculated.

Although not shown, the judgment means 38 adds the information about the modulation such as the pulse width modulation and the power modulation to the detection result of the detection means 35 to collect the recovered toner in the first developing device 2.
It is also possible to adopt a configuration in which it is decided whether to return to No. 3 or to discard as it is without returning.

In the case shown in FIGS. 1 to 3, when the coil spring 46 is normally rotated, the recovered toner is returned to the first developing device 23 by the first returning means 44, and when the coil spring 46 is reversely rotated. The collected toner was sent into the waste toner container 41. However, it is not limited to this,
The invention is configured as shown in FIGS. 6 to 9.

Reference numeral 51 in FIG. 6 is a second returning means. The second return means 51 is the red toner return pipe 5
2 and an auger 53. The red toner return pipe 52 has one end attached to the connecting pipe 45 and the other end connected to the second pipe.
It is attached to the developing device 26. The auger 53 is housed in the red toner return pipe 52 and rotatably provided by a motor (not shown).

Further, as shown in FIG. 7, a rotary shutter 54, which is a shutter member, is provided between the connecting pipe 45 and the waste toner container 41. The rotary shutter 5
4 is a fan-shaped window hole 5 as shown in FIGS. 8 and 9.
Two thin metal discs 54b and 54c having 4a are superposed on each other, and one 54b is rotatably provided around the support shaft 55 with respect to the other 54c. As shown in FIG.
Will be installed by blocking the passage. Then, normally, the two window holes 54a are put together to be in an "open" state so that the inside of the connecting pipe 45 and the inside of the waste toner container 41 are communicated with each other.

However, when the color recording is performed, when the detection result of the detecting means 35, for example, the ratio of the red toner to the black toner is less than 1 as the content of the recovered toner, the determining means 38 returns it to the first developing device 23. When the mixing ratio is 1 or more and less than 100, the determining unit 38 determines to discard, and when the mixing ratio is 100 or more, it is in a range that can be said to be sufficiently red, so the determining unit 38 determines to return to the second developing device 26. .

Then, when the judgment means 38 decides to return it to the first developing device 23, it is returned to the first developing device 23 by the first returning means 44 and recycled as in the above.

When the judging means 38 decides to discard, the coil spring 46 is reversed. Then, the collected toner is put into the connecting pipe 45 through the toner discharge port 40b and sent into the waste toner container 41 through the window hole 54a .

When it is decided by the judging means 38 to return to the second developing device 26, one of the metal disks 54b is rotated to rotate the window 5
4a is displaced, the rotary shutter 54 is closed, and the connecting pipe
The communication between the inside of 45 and the inside of the waste toner container 41 is cut off. Then, the coil spring 46 is reversed to put the collected toner into the connecting pipe 45 from the toner discharge port 40b, the collected toner accumulated therein is put into the red toner returning pipe 52, and the auger 53 rotates to rotate the red toner returning pipe 52. It is returned to the second developing device 26 through the inside and is recycled.

In the embodiment of FIGS. 6 to 9, the toner distributing means 39 is a rotary conveying means for returning the collected toner to the developing device side at the time of forward rotation and sending it to the waste toner container 41 side at the time of reverse rotation. comprising a certain coil spring 46, while having the first returning means 44 for returning and the coil spring 46 to the first developing unit 23 is a current image instrument 1 recovered toner when forward, reverse the coil spring 46 A second returning means for selectively operating the rotary shutter 54 to block the collected toner sent to the waste toner container 41, and to return the collected toner blocked by the rotary shutter 54 to the second developing device 26. 51 is provided. However, although not shown in the figure, the toner distributing means is provided with a rotation conveying means for returning the collected toner to the developing device side at the time of forward rotation and sending it to the waste toner container side at the time of reverse rotation, and when the rotation conveying means is rotated forward The first returning means for returning the collected toner to one developing device and the second returning means for returning the collected toner to another developing device may be selectively operated.

By the way, in all the embodiments described above, the two-color color copying machine using the black toner and the red toner has been described. However, the combination of a plurality of types of toner is not limited to this. The present invention can be applied not only to a two-color copying machine but also to a full-color copying machine. In this case, for example, only the black toner can be recycled based on the detection result of the detecting means. Further, the present invention is not limited to a two-color color copying machine or a full-color copying machine. For example, copying using a non-magnetic toner of black toner that forms a glossy recorded image and a magnetic toner of black toner that forms a dull recorded image in combination. The same can be applied to the machine. Furthermore, the present invention can be applied not only to copying machines, but also to printers, facsimiles, and the like.

[0061]

As described above, according to the first aspect of the invention, when recording is performed in the electrophotographic apparatus using a plurality of types of toner, the mixing ratio of the recovered toner is detected by the detecting means. Based on the detection result, the determining means determines the conveying direction of the collected toner, and the toner is determined based on the determination.
-The collected toner is sorted by the sorting means and the collected toner is collected.
While returning to the developing device 1 by the first returning means,
The collected toner sent to the container side is blocked by the shutter member.
Since it is returned to another developing device by the returning means of 2, it has a simple structure.
A plurality of types of toner can be returned to the respective developing devices, and for example, at least a part of the recovered toner can be recycled for effective use of resources and destruction of the natural environment can be prevented.

[0062] According to the invention described in claim 2, when performing a dot-like write, counted by the count unit the number of dots for each type of toner, by calculating by the calculation unit from the count value, claim 3 According to the invention described in (1), the exposure time for each type of toner is counted by the counting unit, and is calculated by the calculation unit from the count value, so that it is estimated from the mixing ratio of the toner used during development and detected by the detection unit. Since this is done, it is possible to easily detect the mixing ratio of the collected toner.

According to the fourth aspect of the present invention, when the determining means determines the conveying direction, the detection result of the detecting means takes into consideration the recovery rate for each type of toner, so that the mixing ratio of the recovered toner is actually determined. It can be calculated accurately according to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a main part of a two- color color copying machine.

FIG. 2 is an enlarged schematic configuration diagram of a peripheral portion of the toner distributing unit.

FIG. 3 is a schematic configuration diagram of an entire internal mechanism of the two-color color copying machine.

FIG. 4 is a graph showing the relationship for each color, where the horizontal axis represents the number of dots and the vertical axis represents the amount of collected toner.

FIG. 5 is a graph showing the relationship for each color, with the horizontal axis representing the number of dots and the vertical axis representing the amount of collected toner.

FIG. 6 is a schematic configuration diagram of a main part of a two-color color copying machine according to the embodiment of the present invention .

FIG. 7 is an enlarged schematic configuration diagram of a peripheral portion of the toner distributing unit.

FIG. 8 is a plan view of a rotary shutter provided in the peripheral portion thereof.

FIG. 9 is a perspective view thereof.

[Explanation of symbols]

20 Photosensitive Member 23 First Developing Device (Developing Device of 1) 26 Second Developing Device (Other Developing Device) 28 Cleaning Device 35 Detecting Device 36 Counting Unit 37 Calculating Unit 38 Judging Device 39 Toner Sorting Device 41 Waste Toner Container 44 First return means 46 Coil spring (rotary conveyance means) 51 Second return means 54 Rotary shutter (shutter member ) P Paper

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-5-241489 (JP, A) JP-A-4-168485 (JP, A) JP-A-4-336876 (JP, A) JP-A-6- 161332 (JP, A) JP-A-6-118845 (JP, A) JP-A-5-165380 (JP, A) JP-A-2-48692 (JP, A) JP-A-57-161770 (JP, A) JP-A-4-20981 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/01-15/01 117 G03G 15/08-15/095 G03G 21/10

Claims (4)

(57) [Claims] 1. A charging, writing, and developing process is performed to form an image on a photoconductor using a plurality of types of toner, and the image is transferred to record on a sheet, while the image remains on the photoconductor after the transfer. together when removes and collects toner cleaning device
And a detection means for detecting the mixing ratio of the collected toner.
And the conveyance of the collected toner based on the detection result of the detection means.
Based on the decision means that determine the direction and the decision means
In the electronic photographic apparatus, the toner allocating means for allocating the collected toner to the toner allocating means ,
The collected toner is returned to the developer side, and when it is reversed, the waste toner container
Equipped with a rotary transporting means for feeding to the side
When the toner is rotated normally, the collected toner is returned to the first developing device.
While the return transport means is provided, when the rotary transport means is reversed
Operation to selectively feed the waste toner to the waste toner container side.
A shutter member for blocking the collected toner is provided, and the shutter
The collected toner blocked by the member is returned to another developing device.
An electrophotographic apparatus comprising a returning means . 2. When the dot-shaped writing is performed, the toner
A counting unit that counts the number of dots for each type, and the total
With the calculation unit that calculates the mixing ratio from a numerical value, the detection
The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus comprises means. 3. Dew by type of toner when writing.
The electrophotographic apparatus according to claim 1, wherein the detection unit is configured by a counting unit that counts the light time and a calculation unit that calculates the mixing ratio from the count value. 4. The detection result of the detection means is determined by the determination means.
The electrophotographic apparatus according to claim 1, wherein the conveyance direction is determined by taking into consideration the recovery rate for each type of toner to the result .