JPH07244429A - Developing device - Google Patents

Abstract

PURPOSE:To provide a developing device capable of prolonging the life of a device by preventing the storage of degraded toner. CONSTITUTION:When a toner end detector 19 detects the end of toner, only a second carrying member 18 is driven or first only a first carrying member 17 is driven to discharge the toner on the first carrying member 17 to the carrying part, of the second carrying member and then, only it is driven to discharge the toner therein to a toner reservoir part 12. The discharged toner is discharged to a toner cartridge 22 fitted detachably to the toner reservoir part, 12, to be discarded together with the toner cartridge.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device using a one-component developer such as an electrophotographic copying machine, a facsimile, and a printer.

[0002]

2. Description of the Related Art Conventionally, a toner storage portion is provided on a side surface of a developing device, and a first conveying member for conveying and supplying toner from the toner storage portion to a side opposite to the toner storage portion in a longitudinal direction of a toner carrier. Contrary to the first transport member, the second toner transporter collects excess toner not used for development from the opposite side of the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier.
In the developing device having the developing device having the conveying member of the above, when the toner in the toner storage portion is consumed and the toner is exhausted, new toner is supplied to the toner storage portion, or the toner storage portion is replenished. The attached toner cartridge was replaced with a new toner cartridge filled with toner.

[0003]

By the way, in the above-mentioned conventional developing device, when the detection member (toner end detector) detects the toner end, or the image is missing on the output image, it is determined to be the toner end. At this time, even if the toner is almost depleted in the toner storage portion, the toner is not completely depleted on the first and second conveying members, and a certain amount of toner remains. The residual toner after the toner end state is shifted to a larger average particle size and becomes unsuitable for development, the charge amount is low and the image is easily stained, and the ratio of additives such as silica is also high. The toner varied from the initial ratio, and the toner was liable to cause problems such as deterioration in transferability to a transfer sheet even when subjected to development.

Therefore, in the conventional developing device, when new toner is immediately replenished when the toner end state is reached, the deteriorated residual toner as described above is contained in the newly replenished toner. By repeating such toner replenishment, the deteriorated toner is gradually accumulated, and the deteriorated toner is supplied to the development before the end of the toner, so that the density of the developed image decreases Problems such as soiling occurred, and as a result, the life of the device was shortened.

The present invention has been made in view of the above points, and an object thereof is to prevent the accumulation of deteriorated toner,
An object of the present invention is to provide a developing device capable of extending the life of the device.

[0006]

In order to solve the above-mentioned problems, the present invention provides, in claim 1, a toner storage portion provided on a side surface of a developing device and the toner in the longitudinal direction of a toner carrier. A first transport member that transports and supplies toner from the storage unit to the opposite side of the toner storage unit, and, conversely to the first transport member, toner from the opposite side of the toner storage unit in the longitudinal direction of the toner carrier. A developing device having a second transport member for transporting and collecting excess toner that has not been used for development to the storage part, and a toner end detector for detecting the presence or absence of toner in the toner storage part. Drive the first and / or second conveying member based on the detection result,
The toner on the first and / or the second conveying member is discharged to the toner storage section.

Further, in claim 2 and claim 3, the toner is carried from the toner storage part provided on the side surface of the developing device to the opposite side of the toner storage part from the toner storage part in the longitudinal direction of the toner carrier. A first conveying member for supplying and a conversely to the first conveying member, excess toner that has not been used for development is transferred from the side opposite to the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier. In a developing device having a second carrying member for carrying and collecting, and a toner end detector for detecting the presence or absence of toner in the toner storing part, between the toner storing part and the developing device of the carrying part of the second carrying member. A configuration in which an openable / closable toner discharge port and a discharge toner cartridge are provided, or an openable / closable structure that divides the transport unit of the first transport member and the transport unit of the second transport member in the toner storage unit Structure with various partitions To.

Further, in claims 4 and 5, the toner is carried from the toner storage part provided on the side surface of the developing device to the opposite side of the toner storage part in the longitudinal direction of the toner carrier. A first conveying member for supplying and a conversely to the first conveying member, excess toner that has not been used for development is transferred from the side opposite to the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier. In a developing device having a second carrying member for carrying and collecting and a toner end detector for detecting the presence / absence of toner in the toner storage portion, when the toner end detector detects the toner end, an appropriate number of sheets are printed. Toner is supplied to output a black solid image, and the first and second
5. The developing device according to claim 4, wherein the toner on the conveying member is used up, and when the black solid image is output, the transfer paper to which the black solid image is transferred is not fed and the transfer paper is In addition, the transfer device for transferring the black solid image is not operated.

[0009]

According to the present invention, when the toner end detector detects the toner end, only the second conveying member is driven to move the toner on the second conveying member to the toner storing section. Discharge. Then, the discharged toner is discharged to a toner cartridge that is detachably attached to the toner storage portion, and is discarded together with the toner cartridge.
Alternatively, when the toner end detector detects the toner end, first, only the first transport member is driven to discharge the toner on the first transport member to the transport section of the second transport member, and then, Only the second transport member is driven to discharge the toner on the second transport member to the toner reservoir. Then, the discharged toner is discharged to a toner cartridge that is detachably attached to the toner storage portion, and is discarded together with the toner cartridge.

According to a second aspect of the present invention, there is provided the second developing device.
An openable toner discharge port and a discharge toner cartridge are provided between the toner storage section of the conveyance section of the conveyance member of No. 2 and the developing unit. When the toner end detector detects the toner end, the toner discharge port Is opened, and the first and second transport members are driven to discharge the toner on the first and second transport members to the discharged toner cartridge.

According to another aspect of the present invention, in the developing device, a separable partition for dividing the first conveying member and the second conveying member is provided in the toner storage portion, and the toner end detector is used as the toner end. When the above is detected, the partition wall is closed, and the toner on the first and second conveying members is discharged to the conveying portion of the second conveying member in the toner storage portion.

In the developing device of the fourth aspect, when the toner end detector detects the toner end, the toner is supplied so as to output an appropriate number of black solid images,
The toner on the first and second conveying members is almost used up.

In the developing device having the structure described in claim 5, when the toner end detector detects the toner end, the transfer paper is not fed and the transfer for transferring the black solid image to the transfer paper is performed. The toner is supplied to output an appropriate number of black solid images without operating the container, and the first and second
Use up almost all the toner on the transport member. As a result, the toner provided on the photoconductor to form a solid black image is removed and collected from the photoconductor by the cleaning member for cleaning the photoconductor, and is discarded.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a first embodiment of the present invention, and FIG. 2 shows a central cross section thereof. The first embodiment is a developing device that carries out the invention according to claim 1, and this developing device is an electrostatic latent image carrier on which an electrostatic latent image is formed in an electrophotographic image forming apparatus. The one-component toner is disposed on the photoconductor drum in proximity to the carrier (photoconductor drum) to develop the electrostatic latent image formed on the photoconductor drum.

The developing device according to the first embodiment includes a developing device 1
1. A toner reservoir 12 is provided on one side (side) of the developing device 11. In the developing device 11, a toner carrier 14 composed of a developing roller, a replenishing roller 15 having elasticity, and a toner layer are provided in a developing container 13. The thickness regulating member 16 and the toner carrier 14 convey the toner from the toner reservoir 12 to the opposite side in the longitudinal direction of the toner carrier 14. First, the carrier member 17 and conversely, the toner carrier 14.
A second transport member 18 for transporting and collecting excess toner that has not been used for development from the side opposite to the toner storage portion 12 in the longitudinal direction of the developing container 13;
A toner end detector 19 for detecting the toner end inside is provided.

As shown in FIG. 2, the developing roller 14 is disposed near the electrostatic latent image carrier (not shown) through the opening of the developing container 13. In addition, the supply roller 15,
The first transport member 17 and the second transport member 18 are arranged parallel to the developing roller 14. Since the replenishing roller 15 is provided so as to contact the developing roller 14 and the developing container 13, the first toner conveying space 2
0 and the second toner carrying space 21
3, the first toner transport member 17 is disposed in the first toner transport space 20, and the toner transport member 18 is disposed in the second toner transport space 21.

A toner cartridge 22 is removably mounted in the toner storage section 12, and one-component toner is supplied from the toner cartridge 22 and stored therein. The first toner carrying member 17 and the second toner carrying member 18 are
It has a conveying part consisting of ribs formed in a spiral shape,
The end portion of the conveying portion extends into the toner storage portion 12 (FIG. 1), and is rotated and driven counterclockwise in FIG. 2 by a driving portion (not shown). Further, the first toner conveying member 17 conveys the toner from the toner reservoir 12 to the opposite side in the longitudinal direction of the developing roller 14 in the first toner conveying space 20 by the rotation of the first toner conveying member 17 and the replenishing roller 15. The toner is supplied over the entire length of.

In FIG. 2, the developing roller 14 is rotationally driven in the counterclockwise direction by the driving unit, and the replenishing roller 15 is
It is rotated clockwise by the drive unit. The toner supplied from the first toner replenishing member 17 to the replenishing roller 15 is conveyed by the replenishing roller 15 and is supplied to the developing roller 14
The toner is supplied to the developing roller 14 while being charged at the contact portion between the developing roller 14 and the replenishing roller 15, and is carried on the surface of the developing roller 14. The toner carried on the surface of the developing roller 14 is
Excess toner was uniformly scraped off by the toner layer thickness regulating member 16 and regulated to a uniform and predetermined thickness, and the toner was supplied onto the electrostatic latent image carrier to be formed into an electrostatic latent image carrier. Develop the electrostatic latent image.

The excess toner scraped off from the developing roller 14 by the toner layer thickness regulating member 16 falls into the second toner carrying space 21 due to its own weight, and the second toner carrying member 18 causes the developing roller 14 to move. Further, the toner is conveyed from the side opposite to the toner reservoir 12 to the toner reservoir 12 with respect to the longitudinal direction of the supply roller 15, and is collected in the toner reservoir 12.

When the toner in the toner storage section 12 is consumed and runs low, new toner is supplied from the toner cartridge 22 mounted on the toner storage section 12 to the toner storage section 12 by free fall. When all the toner in the toner cartridge 22 is supplied, the toner end detector 19
Detects the toner end and becomes the toner end. At the time of this toner end, after the control to be described later is executed, the cartridge 22 that has finished supplying toner is replaced with a new toner cartridge filled with new toner.

In the developing device of the first embodiment, when the toner end detector 19 detects the toner end of the toner cartridge 22, only the second toner carrying member 18 is rotationally driven to carry out the second toner carrying operation. The toner remaining in the space 21 is controlled so as to be collected in the toner storage unit 12. As a result, the residual toner collected in the toner storage unit 12 is discharged into the toner cartridge 22 that is emptied by the rotation of the developing device. That is,
In this embodiment, as the developing device, the developing device 1 shown in FIG.
It is composed of a revolver type developing device as shown in FIG. This revolver type developing device is, for example, as shown in FIG. 3, a magenta developing device 23M, a cyan developing device 23C, a yellow developing device 23Y,
And a revolver developing device 23 composed of a black developing device 23K. Each developing device rotates to correspond to the developing portion of the photosensitive drum 24, thereby forming each color component formed on the photosensitive drum 24. The electrostatic latent image is sequentially developed with toner of a predetermined color.

FIG. 4 shows how the residual toner is collected in this developing device. In FIGS. 3 and 4, the toner cartridge 22 mounted in the toner reservoir 12 rotates with the rotation of the developing device. And the developing device 11
From FIG. 4 (a) to FIG. 4 (b), FIG. 4 (c), FIG.
By rotating once to (d) and FIG. 4 (e),
The residual toner collected in the toner storage portion 12 by the toner end is sequentially moved by its own weight and is discharged from the toner storage portion 12 into the toner cartridge 22.

The rotation direction of the developing device at this time is opposite to that at the time of toner supply. A commonly used detector can be used as the toner end detector 19 for detecting the amount of toner. For example, a detector that uses transmission or reflection of light, or a resistor or an inductance electric sensor. Examples include detectors that utilize dynamic changes.

The residual toner (deteriorated toner) thus discharged into the toner cartridge 22 is removed from the developing device when the toner cartridge 22 is replaced with a new toner cartridge.

By the way, in the developing device of the first embodiment, the deteriorated toner can be collected even by the following control. That is, in this control, when the toner end of the toner cartridge 22 is detected by the toner end detector 19, first, only the first conveying member 17 is driven to remove the deteriorated toner on the first conveying member 17 to the second state. And discharges it to the transport section (second transport space 21) of the transport member 18 of
After that, only the second conveying member 18 is driven to remove the deteriorated toner on the conveying portion of the second conveying member 18 from the toner accumulating portion 12.
To collect. As in the case of the control described above, this deteriorated toner is discharged into the toner cartridge 22 by the rotation of the developing device, and then is removed from the developing device when the toner cartridge is replaced with a new toner cartridge.

FIG. 5 shows a second embodiment of the developing device of the present invention. In the second embodiment, an openable / closable toner discharge port 27 and a discharged toner cartridge 28 are provided between the toner storage portion 12 of the conveying portion of the second conveying member 18 and the developing device 11. . In the developing device of the second embodiment,
The toner cartridge 22 is detected by the toner end detector 19.
When the toner end of is detected, the toner discharge port 27 is opened, the first and second transport members 17 and 18 are rotationally driven, and the deteriorated toner on the first and second transport members 17 and 18 is The toner is discharged into the discharged toner cartridge 28 through the toner discharge port 27. Here, the discharged toner cartridge 2
8 and the toner cartridge 22 are integrally formed, the deteriorated toner can be automatically discarded by replacing the empty toner cartridge 22, and the handling thereof becomes simpler. According to the developing device of the second embodiment, at the toner end, the first and second conveying members 1
Since the deteriorated toner on 7, 18 can be discharged, the developing container 1
Accumulation of deteriorated toner in 3 is eliminated.

FIG. 6 shows a third embodiment of the developing device of the present invention. In the third embodiment, in the toner reservoir 12,
An openable / closable partition wall 29 that divides the first transport member 17 and the second transport member 18 is provided. In the developing device of the third embodiment, when the toner end detector 19 detects the toner end of the toner cartridge 22, the partition 29 is first moved in the direction of the arrow and closed, and the first and second conveying members are moved. 17 and 18 are rotationally driven, and the deteriorated toner on the first and second conveying members 17 and 18 is discharged to the conveying portion of the second conveying member 18 in the toner storage portion 12.
Next, the partition wall 29 is opened, and the deteriorated toner discharged to the transport portion of the second transport member 18 in the toner storage portion 12 is
Similar to the case of the first embodiment shown in FIG. 3, the toner is collected in the toner cartridge 22 by the rotation of the developing device.
The deteriorated toner collected in the toner cartridge 22 is removed from the developing device when the toner cartridge 22 is replaced. According to the developing device of the third embodiment,
At the time of the toner end, the first and second transport members 17,
Since the deteriorated toner on 18 can be discharged, the deteriorated toner in the developing container 13 does not accumulate.

Next, a fourth embodiment of the present invention described in claim 4 will be described. In the developing device of the fourth embodiment, when the toner end detector 19 detects the toner end of the toner cartridge 22, the normal image forming process by front writing is forcibly executed. As a result, the toner is supplied onto the photosensitive drum 24 in order to output an appropriate number of black solid images, and the deteriorated toner on the first and second conveying members 17 and 18 is almost used up. According to the developing device of the fourth embodiment, since the deteriorated toner on the first and second conveying members 17 and 18 is delivered out and does not exist at the time of the toner end, the deteriorated toner in the developing container 13 is removed. There is no accumulation. Here, the number of black solid images to be output is preferably 30 to 50. Further, when the absolute value of the developing bias voltage is increased to control the development so as to be accelerated, the deteriorated toner on the first and second conveying members 17 and 18 is consumed with a smaller number of transfer paper outputs. It is more preferable because it can.

Next, a fifth embodiment of the present invention described in claim 5 will be described. In the developing device of the fifth embodiment, when the toner end of the toner cartridge 22 is detected by the toner end detector 19, the transfer paper is not fed by the forced front writing, and the transfer paper is black. The image forming process is performed without operating the transfer device for transferring the solid image. As a result, the toner is supplied onto the photosensitive drum 24 in order to output an appropriate number of black solid images, and the deteriorated toner on the first and second conveying members 17 and 18 is almost used up. As a result, the deteriorated toner that is delivered onto the photoconductor drum 24 and forms a solid black image is removed and collected from the photoconductor drum 24 by a cleaning member (not shown) for cleaning the photoconductor drum 24 and discarded. To be done. According to the developing device of the fifth embodiment, the deteriorated toner on the first and second conveying members 17 and 18 is delivered and does not exist at the time of the toner end, so that the deteriorated toner in the developing container 13 is removed. There is no accumulation.
Further, the transfer paper is not wasted when forming a solid black image.

[0030]

According to the developing device of the first aspect of the present invention, at the time of the toner end, at least the deteriorated toner on the second conveying member can be discharged, so that the accumulation of the deteriorated toner in the toner reservoir is reduced. As a result, the life of the developing device can be extended.

According to the developing device of the second to fifth aspects of the present invention, since the deteriorated toner on the first and second conveying members can be discharged, it is possible to eliminate the accumulation of the deteriorated toner in the toner reservoir. As a result, the life of the developing device can be extended.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a developing device according to a first embodiment of the present invention.

FIG. 2 is a central cross-sectional view of the developing device shown in FIG.

FIG. 3 is a schematic cross-sectional view of a developing device configured by combining four developing devices in the first embodiment.

FIG. 4 is an operation mode diagram showing how residual toner is collected in the developing device of the first embodiment.

FIG. 5 is a schematic sectional view of a developing device according to a second embodiment of the present invention.

FIG. 6 is a schematic sectional view of a developing device according to a third embodiment of the present invention.

[Explanation of symbols]

 11 Developing Device 12 Toner Reservoir 13 Developing Container 14 Toner Carrier 15 Replenishing Roller 16 Toner Layer Thickness Controlling Member 17 First Conveying Member 18 Second Conveying Member 19 Toner End Detector 20 First Toner Conveying Space 21 First 2 toner transport space 22 toner cartridge 23 revolver developing device 24 photoconductor drum 27 toner discharge port 28 discharge toner cartridge 29 partition wall

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number in the agency FI Technical display location G03G 21/10 (72) Inventor Utsugu Fujishiro 1-6-3 Nakamagome, Ota-ku, Tokyo In Ricoh Co., Ltd. (72) Inventor Chiyako Kobayashi 1-3-3 Nakamagome, Ota-ku, Tokyo ・ In Ricoh Co., Ltd.

Claims (5)

[Claims] 1. A toner storage portion provided on a side surface of a developing device, and a first conveying member for conveying and supplying toner from the toner storage portion to a side opposite to the toner storage portion in a longitudinal direction of a toner carrier. Contrary to the first transport member, the second toner transporter collects excess toner not used for development from the opposite side of the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier.
And a toner end detector for detecting the presence / absence of toner in the toner reservoir, the first and / or second conveying member is detected based on the detection result of the toner end detector. A developing device, which is driven to discharge the toner on the first and / or the second conveying member to the toner reservoir. 2. A toner storage portion provided on a side surface of a developing device, and a first conveying member for conveying and supplying toner from the toner storage portion to a side opposite to the toner storage portion in a longitudinal direction of a toner carrier. Contrary to the first transport member, the second toner transporter collects excess toner not used for development from the opposite side of the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier.
And a toner end detector for detecting the presence / absence of toner in the toner storage section, the openable and closable toner is provided between the toner storage section and the developing section of the transfer section of the second transport member. A developing device provided with an outlet and an ejected toner cartridge. 3. A toner reservoir provided on the side surface of the developing device, and a first transport member for transporting and feeding toner from the toner reservoir to the opposite side of the toner reservoir in the longitudinal direction of the toner carrier. Contrary to the first transport member, the second toner transporter collects excess toner not used for development from the opposite side of the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier.
And a toner end detector for detecting the presence / absence of toner in the toner storage section, the transfer section of the first transfer member and the second transfer member in the toner storage section. A developing device, which is provided with a partition wall that can be opened and closed so as to divide the part. 4. A toner storage portion provided on a side surface of a developing device, and a first conveying member for conveying and supplying toner from the toner storage portion to a side opposite to the toner storage portion in a longitudinal direction of a toner carrier. Contrary to the first transport member, the second toner transporter collects excess toner not used for development from the opposite side of the toner reservoir to the toner reservoir in the longitudinal direction of the toner carrier.
In a developing device having a conveying member of No. 1 and a toner end detector for detecting the presence / absence of toner in the toner reservoir, when the toner end detector detects the toner end,
A developing device characterized in that toner is supplied so as to output an appropriate number of black solid images, and the toner on the first and second conveying members is almost used up. 5. The developing device according to claim 4, wherein when the black solid image is output, the transfer paper to which the black solid image is transferred is not fed, and the black solid image is transferred to the transfer paper. The developing device is characterized in that the transfer device is not operated.