JPH0719114B2 - Developer recycling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an image forming apparatus such as a copying machine, a facsimile machine, and the like, which is developed in a developing device for the purpose of reusing the developer in the cleaning device. The present invention relates to an agent recycling device.

(Prior Art) Generally, the developer remaining on the photoconductor after transfer in an image forming apparatus such as a copying machine is removed by a cleaning device,
Although collected, in order to reuse the collected developer, a developer recycling apparatus has conventionally been proposed which conveys the developer in the cleaning device into the developing device.

FIG. 7 shows an example of such a device.
In the figure, a developing device 102 and a cleaning device 103 are provided on the periphery of the photosensitive drum 101, and a recycling passage 104 communicating with both is provided between the developing device 102 and the cleaning device 103. The end of the recycling passage 104 is a wall 104a, and an opening 102a which is an entrance to the developing device 102 is located immediately below the wall 104a. Further, a feeding member 105 for feeding the developer into the developing device 102 through the opening 102a is provided across the width direction of the developing device 102.

Inside the recycling passage 104, there is provided a spiral conveying member 106 extending to the end thereof and having a constant diameter and pitch. By rotating the conveying member 106, the cleaning device 103 to the developing device 102 are provided. The developer is conveyed toward.

However, not all of the developer carried by the carrying member 106 to the end of the recycling passage 104 is carried into the developing device 102 through the opening 102a. When the fluidity is lowered, the developer is entangled with the surface of the conveying member 106, and the opening 1
It is conveyed toward the wall 104a without falling to 02a. When the developer is pushed into the wall 104a one after another in this manner, the developer may be deposited on the end portion of the transport member 106 to prevent the transport member 106 from rotating, and the transport member 106 may be locked. there were.

(Object of the Invention) In view of the above circumstances, an object of the present invention is to provide a developer recycling apparatus that can perform stable recycling even in an environment where the fluidity of the developer is low.

(Structure of the Invention) The present invention includes a photoconductor, and a developing device and a cleaning device as image forming process means arranged on the periphery of the photoconductor, wherein the developer contained in the cleaning device is In a developer recycling device which conveys into a developing device, a recycling passage provided between the developing device and a cleaning device and communicating between the inside of the developing device and the cleaning device, and a cleaning device which is inserted into the recycling passage and driven to rotate are cleaned. A transport member for transporting the developer collected in the device toward the developing device, and the transport member has a transport flow rate of the developer at a terminal end portion thereof smaller than a flow rate at an upstream portion thereof. It is formed in.

With such a configuration, even when the developer is entangled with the transport member, the transport flow rate of the developer at the end portion of the transport member is small, so that the developer is pushed into this portion one after another and the developer accumulates. There is nothing to do and the locked state does not occur.

(Embodiment) A first embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, a document table 2 is provided on the upper surface of an electrostatic copying machine main body 1, and in the main body 1, a paper feeding section 3, a photosensitive drum 4, a main charging device 5, an exposure device 6, a developing device. 7, a cleaning device 8, a transfer charging device 9, a peeling charging device 10, a fixing device 11 and a paper discharge tray 12 are provided. The photosensitive drum 4 is connected to a drive shaft of a main motor (not shown) and is rotationally driven in the direction of the arrow shown.

The photosensitive drum 4, the developing device 7, the cleaning device 8 and the like are housed in a case as a replaceable kit, and a single unit U as shown in FIGS. I am configuring. This unit U is a rail
It is installed in the copier freely while being guided by 1a and 1b. Further, in this unit U, a cylindrical recycling passage 13 communicating with both the developing device 7 and the cleaning device 8 is provided on the side of the developing device 7 and the cleaning device 8. Inside the recycling passage 13, a spirally driven spiral (spiral) shape is provided. A transport member 14 is provided.

The developing device 7 has a cylindrical communication portion 7a that projects laterally from the side portion of the case. A portion of the recycling passage 13 on the downstream side is disposed above the communication portion 7a (see FIGS. 2 and 3), and the communication portion 7a and the recycling passage 13 are opened (communication between the developing device and the recycling passage). (Portion) 22 and communicates with each other at the periphery of the opening 22.
A sponge 41 for sealing is provided on the joint surface between the wall member of the recycling passage 13 and the wall member of the communication portion 7a.

The developing device 7 has a developer accommodating portion 15 in the upper part thereof. The developer storage section 15 is opened downward, and a start agent storage section 15a for storing a developer (start agent) in which toner and carrier are premixed and a toner storage section 15b for storing only toner. It consists of A seal member 16 is provided below the developer accommodating portion 15. The seal member 16 is attached to the lower portion of the developer accommodating portion 15 in a state where the seal member 16 is folded back at an intermediate portion thereof, whereby the developer in the developer accommodating portion 15 is sealed. The tip of this seal member 16 is led out through the slit hole 45 of the unit U, and the seal member 16 is pulled out by pulling this tip in the direction of the arrow in FIG. It is designed so that it can be eaten.

Below the seal member 16, a carry-in roller 17 and a replenishing roller are provided.
A stirring roller 19, a stirring roller 19, and a developing roller 20 are provided, and a toner control sensor 21 that detects a mixing ratio of the toner of the developer and the carrier in the developing device 7 is provided substantially above the developing roller 20. ing.

The carry-in roller 17 is located below the toner storage portion 15b and upstream of the replenishing roller 18, and in the developing device 7, the front end portion is fitted and inserted into the communication portion 7a.
It extends in the width direction of the developing device 7 from immediately below 22 to the opposite side surface. A spiral blade 17a is formed on the opening 22 side of the carry-in roller 17, and a spiral blade 17b in the opposite direction is formed on the opposite side, and extends in the axial direction at the intermediate portion. Two flat plates 17c are provided. Then, by being rotationally driven in a predetermined direction by a driving means described later, the toner is conveyed from the communication portion 7a toward the inside of the developing device 7 on the side of the opening 22 and a reverse conveying force is applied to the toner on the opposite side. It is supposed to do.

The replenishment roller 18 is located below the boundary between the start agent storage portion 15a and the toner storage portion 15b, and is in contact with the partition member 23 in the developing device 7 and the lower surface inside the case of the developing device 7, and It divides the left and right parts within 7.

The rear ends of the carry-in roller 17 and the replenishing roller 18 project outside the case of the developing device 7, and gears 24 and 25 are provided on these projecting portions, respectively, and these gears 24 and 25 mesh with each other. A coupling gear 26 is provided. A motor (not shown) for toner replenishment is connected to the coupling gear 26 via an appropriate control system, and the carry-in roller 17 and the replenishing roller 18 are driven in conjunction with each other according to the output of the toner control sensor 21. The toner density in the developing device 7 is kept constant by replenishing the toner by this driving.

Similarly, gears 27 and 28 are also provided at the rear ends of the developing roller 20 and the agitating roller 19, and a coupling gear 29 that meshes with the gears 27 and 28 is provided between the gears 27 and 28. By connecting a predetermined drive source to the developing roller 20 and the stirring roller 19, the developing roller 20 and the agitating roller 19 are interlocked with each other during development. In FIG. 4 and FIG. 5, reference numeral 30 is an ear cutting plate for cutting the ear of the developer on the developing roller 20.

On the other hand, the cleaning device 8 has the developing device 7 at the peripheral edge of the photosensitive drum 4 with respect to the rotation direction of the photosensitive drum 4.
And a lower blade 31b for scraping off the toner remaining after the transfer onto the photosensitive drum 4, and a lower blade 31b for guiding the scraped toner to the bottom without zeroing it. . Like the developing device 7, the cleaning device 8 also has a cylindrical communicating portion 8a that projects laterally from the case side portion, and below the communicating portion 8a (see FIGS. 2 and 3). ) Is disposed at the upstream side of the recycling passage 13, and the communication portion 8a and the recycling passage 13
And are communicated with each other through the opening 32.

At the bottom of the cleaning device 8, a carry-out spiral 33 for carrying out the toner collected as described above to the recycling passage 13 is provided. A front end portion of the carry-out spiral 33 is fitted and inserted into the communication portion 8a and further protrudes from an end portion of the communication portion 8a, and a gear 35 is provided on the protruding portion. The rear end portion projects outside the case of the cleaning device 8, and the gear 34 provided on this projecting portion is connected to the gear 43 provided on the shaft 42 of the photosensitive drum 4. As a result, the carry-out spiral 33 is rotationally driven in association with the photosensitive drum 4, and the toner in the cleaning device 8 is conveyed toward the opening 32.

The conveying member 14 in the recycling passage 13 is composed of a coil spring or the like, the gear 35 and the intermediate gear 3 meshing with the gear 35.
6, a screw gear 38 coaxial with the gear 37 that meshes with the gear 36,
Also, it is connected to the carry-out spiral 33 via a screw gear 39 that meshes with the screw gear 38 and is directly connected to the conveying member 14, and the carry-out spiral 33 is rotated by the rotation of the photosensitive drum 4.
It is designed to be rotated together with it. The shape of the conveying member 14 is set so that the conveying member 14 conveys the toner in the recycle passage 13 toward the developing device 7 by the rotational drive, and the conveying flow rate at the end portion of the conveying member 14 is on the upstream side. Transport member 14 so that it is smaller than the part
The diameter is set so as to decrease from the substantially middle portion to the end.

Next, the operation of the above device will be described. First, before the unit U is used, the developer accommodating portion is provided in the developing device 7.
The starter and toner are in a sealed state. From this state, by pulling out the seal member 16 in the direction of the arrow in FIG.
The start agent is supplied to the 20 side, and the toner is supplied to the carry-in roller 17 side. By operating the copy switch, the photosensitive drum 4 is activated, and the developing roller 20 and the agitating roller 19 are interlocked with each other to perform development. At this time, the rotation of the photosensitive drum 4 is transmitted to the carry-out spiral 33 via the gears 43 and 34, and the carry-out spiral 33 is further conveyed.
The rotation of 33 is transmitted to the conveying member 14 via the gears 35, 36, 37 and the screw gears 38, 39, and the carrying-out spiral 33 and the conveying member 14 are rotationally driven as the photosensitive drum 4 operates. Has been done.

After the development is performed in this manner, the toner remaining on the photosensitive drum 4 is removed by the blade 31a and stored in the cleaning device 8. The toner is opened by the carry-out spiral 33 which is interlocked with the photosensitive drum 4.
It is carried out toward 32 and sent into the recycling passage 13.

The toner sent into the recycling passage 13 is made to flow along the lower surface of the recycling passage 13 by the conveying member 14 which is rotationally driven as described above, and the developing device 7
Be transported to. The flow rate of the toner is limited at the end of the conveying member 14 at a point where the diameter of the conveying member 14 becomes smaller, so that the toner flows from the end of the conveying member 14 through the opening 22 to the communicating portion of the developing device 7. 7a
The toner having a limited flow rate fed into the inside is separated into the toner which is subjected to the conveyance resistance when the diameter becomes small and escapes to the space above the recycling passage 13 above it.

On the other hand, the carry-in roller 17 and the replenishing roller 18 are driven in conjunction with each other while being controlled by the output of the toner control sensor 21, and by being driven in this way, the carry-in roller 17 is the toner sent to the communicating portion 7a. Developing device 7
Then, the replenishing roller 18 replenishes the developing roller 20 side with a mixture of the toner sent from the carrying-in roller 17 and the toner supplied from the toner storing portion 15b.

For example, when the fluidity of the toner is lowered, such as when the humidity is high, the toner is conveyed while being entangled with the surface of the conveying member 14. At this time, conventionally, the toner transported to the downstream side of the transport member 14 at a constant transport flow rate was pushed into the end portion of the transport member 14 and accumulated, but in the device of the present invention, the toner is transported at the end portion. The flow rate is limited, and as described above, a part of the toner is released to the space above the recycling passage 13 at the portion where the diameter of the conveying member 14 becomes smaller, and only the toner having a limited flow rate is opened. Since the toner is conveyed toward, the toner is not pushed into the end portion of the conveying member 14 one after another even if it is entangled with the conveying member 14, and is smoothly carried into the developing device through the opening 22. Therefore, even under such an environment where the fluidity of the toner is low, the conveying member 14
It is possible to stably recycle the toner without causing the lock of the toner.

Next, a second embodiment will be described with reference to FIG. Here, the spiral pitch of the end portion of the conveying member 14 'is smaller than that of the upstream side portion thereof, and the shape of the conveying member 14' is set so that the conveying speed of the end portion is small. Even in such a structure, the transport flow rate at the end portion of the transport member 14 'is smaller than that at the upstream side, and therefore the same effect as that of the above-described embodiment can be obtained. The shapes of the transport members 14 and 14 'may be such that the transport flow rate gradually decreases toward the end, or may rapidly decrease.

Further, in each of the above-mentioned embodiments, the coil spring-shaped members are used as the conveying members 14 and 14 '. However, when a roller composed of spiral blades is used as the conveying member, the spiral blades of the roller are formed at the end portions thereof. By reducing the difference between the inner diameter dimension and the outer diameter dimension, the transport flow rate can be reduced,
As a result, the same effect as described above can be obtained.

(Effect of the Invention) As described above, according to the present invention, in the developer recycling device including the recycling passage that communicates the developing device and the cleaning device, and the conveying member that conveys the developer in the recycling passage, Since the developer transport flow rate at the end portion of the transport member is smaller than that at the upstream side, even if the developer is entangled with the transport member, the developer may be pushed into the end portion of the recycling passage one after another. There is no accumulation on the end portion of the transport member. . Therefore, even in an environment where the fluidity of the developer is reduced, such as when the humidity is high, the accumulated developer does not hinder the driving of the transport member, and stable recycling can be performed.

[Brief description of drawings]

1 is a cutaway side view of the structure of a copying machine equipped with the toner recycling device of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 3, and FIG. 3 is a unit equipped with the toner recycling device. FIG. 4 is a broken side view of the unit, FIG. 4 is a broken side view of the developing device in the unit, and FIG.
FIG. 7 is a cutaway side view of a unit including a toner recycling device in the second embodiment, and FIG. 7 is a partially cutaway side view of a conventional developer recycling device. 4 ... Photosensitive drum, 7 ... Developing device, 8 ... Cleaning device, 13 ... Recycle passage, 14, 14 '... Conveying member, U ... Unit.

Claims (5)

[Claims] 1. A photosensitive member, and a developing device and a cleaning device as image forming process means arranged on the periphery of the photosensitive member, wherein the developer contained in the cleaning device is placed in the developing device. In the developer recycling device to be conveyed, a recycling passage provided between the developing device and the cleaning device and communicating the inside of the developing device and the cleaning device, and a recycling passage inserted into the recycling passage and rotationally driven are collected in the cleaning device. And a transport member for transporting the developer toward the developing device, and the transport member is formed such that the transport flow rate of the developer at the end portion thereof is smaller than the flow rate at the upstream side portion thereof. A developer recycling device characterized in that 2. The developer recycling device according to claim 1, wherein the conveying member is formed in a spiral shape. 3. The developer recycling apparatus according to claim 2, wherein the conveying member has a diameter of a terminal end portion smaller than a diameter of an upstream side portion. 4. The developer recycling device according to claim 2, wherein the conveying member has a spiral pitch at a terminal end portion thereof smaller than a pitch at an upstream portion thereof. 5. The developer recycling device according to any one of claims 1 to 4, wherein the developing device and the cleaning device are configured as a single unit.