JPH083676B2 - Image forming apparatus with toner recycling function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is provided in a copying machine, a facsimile or the like, and has a toner recycling function of returning the toner collected in the cleaning device to the developing device for the purpose of reuse. The present invention relates to an image forming apparatus having a.

(Prior Art) Generally, the toner remaining on the photoconductor after transfer in a copying machine or the like is removed and collected by a cleaning device. However, since the toner collected in this way is reused, the toner in the cleaning device is conventionally removed. An image forming apparatus has been proposed which has a toner recycling function such that the toner is conveyed into the developing device.

As such a device, there is a device provided with a recycle passage that connects the inside of the cleaning device and the inside of the developing device, and a recycle system that conveys the toner in the cleaning device into the developing device through the recycle passage. . In such a structure, the toner contained in the cleaning device is collected by the recycling system, carried into the developing device, and reused.

By the way, before using the developing device, a developer (in the case of a two-component developer, a starter and a replenishing toner in which a toner and a carrier are mixed in advance) is previously stored therein. In order to prevent the deterioration of the developer, it is necessary to seal the inside of the developing device. However, if the developing device and the cleaning device are simply communicated with each other through the recycling passage as described above, it is difficult to completely seal the developer, and both devices are inclined especially during the transportation of the developing device and the cleaning device. In this case, there is a problem that the developer flows into the cleaning device through the recycling passage. Therefore, there has been a demand for a recycling device capable of sealing such a developer with a simple structure.

(Object of the Invention) In response to the above-mentioned demand, the present invention provides a recycling passage for toner recycling, keeps the developer in the developing device in a sealed structure with a simple structure before use, and enables smooth start of use. An object is to provide an image forming apparatus having a toner recycling function.

(Structure of Invention) The present invention is one.

According to such a configuration, the lower opening of the developer accommodating portion is closed by the seal member, and the carry-in roller that is a recycled toner carry-in portion into the developing device is provided below the seal member, so that the developer before use can be used. At this stage, both the starting agent and the toner in the developer accommodating portion are kept sealed. Moreover, if the seal member is removed from this state, the start agent in the start agent storage unit will drop to the downstream side (development unit side) of the replenishment mechanism, and the toner in the toner storage unit will be on the carry-in roller on the upstream side of the replenishment mechanism. Since it falls, the above-mentioned starter can be used immediately, and the new toner is mixed well with the recycled toner carried in by the carry-in roller after the start of use.

Embodiment An 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 the electrostatic copying machine body 1.
The main body 1 includes a paper feed unit 3, a photosensitive drum 4, a main charging device 5, an exposing device 6, a developing device 7, a cleaning device 8, a transfer charging device 9, a peeling charging device 10, and a fixing device. An apparatus 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 one replaceable kit, and a single unit U as shown in FIGS. Make up. The unit U is provided so as to be freely inserted into and removed from the copying machine while being guided by the rails 1a and 1b. Further, in this unit U, the developing device 7
A cylindrical recycle passage 13 communicating with the cleaning device 8 is provided on the side of the cleaning device 8, and a conveying spiral (conveying mechanism) 14 is provided in the recycle passage 13. The carrying spiral 14 constitutes a collecting and carrying mechanism together with a carrying-out spiral (carrying-out mechanism) 33 described later.

The developing device 7 has a cylindrical communication portion (communication portion with the recycling passage) 7a that projects laterally from the case side portion. A portion on the downstream side of the recycling passage 13 is arranged above the communicating portion 7a (see FIGS. 2 and 3), and the communicating portion 7a and the recycling passage 13 communicate with each other through the opening 22, and A sponge 41 for sealing is provided on the joint surface of the wall member of the recycling passage 13 and the wall member of the communication portion 7a at the peripheral edge of the opening 22.

The developing device 7 has a developer accommodating portion 15 on its upper part.
The developer accommodating portion 15 is opened downward, and a developer (starting agent) in which toner and carrier are premixed.
And a toner storage portion 15b in which only toner is stored. A seal member 16 is provided below the developer accommodating portion 15.

The seal member 16 has its base end portion 16a adhered to the outer surface of the rear wall 15c of the developer accommodating portion 15 and the intermediate portion 16b adhered to the outer surface of the front wall 15d of the developer accommodating portion 15. Further, it is folded back at the intermediate portion 16b, and the tip portion 16c is led out to the outside through the slit hole 45 of the unit U. The communication portion 7a and the opening 22 are located on the opposite side of the developer accommodating portion 15 with the seal member 16 as a boundary, that is, on the downstream side of the seal member 16, and the developer is sealed by the seal member 16. The developer is stored in the storage portion 15. Then, the seal member 16 is pulled out by pulling the tip portion 16c in the direction of the arrow in FIG. 5, and the sealing is released.

Below the seal member 16, a carry-in roller 17, a replenishing roller (replenishing mechanism) 18, a stirring roller 19, and a developing roller (developing section) 20 are provided, and further, the developing roller 20.
A toner control sensor for detecting the mixing ratio of the toner of the developer and the carrier in the developing device 7 substantially above
21 are provided.

The carry-in roller 17 is located below the toner accommodating portion 15b and upstream of the replenishing roller 18. In the developing device 7, the front end portion is inserted into the communication portion 7a. And extends in the width direction of the developing device 7 from directly below to the side surface on the opposite side. A spiral blade 17a is formed on the side of the opening 22 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 an intermediate portion thereof. Two flat plates 17c are provided. The toner is carried into the developing device 7 from the communication portion 7a on the opening 22 side by being rotationally driven in a predetermined direction by a driving unit described later, and a reverse conveying force is applied to the toner on the opposite side. It is supposed to.

The replenishing roller (replenishing mechanism) 18 is the above-mentioned start agent storage section.
It is located below the boundary between the toner storage portion 15b and the toner storage portion 15a, and is in contact with the partition member 23 inside the developing device 7 and the lower surface inside the case of the developing device 7, and partitions the left and right parts inside the developing device 7. There is. This supply roller 18
By being rotationally driven, the toner is replenished from the carry-in roller 17 side to the developing roller 20 side.

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 at these projecting portions. These gears 2
A coupling gear 26 meshing with both is provided between 4 and 25, and a toner replenishing motor (not shown) is connected to the coupling gear 26 via a control device 44. The control device 44 controls the interlocking driving of the carry-in roller 17 and the replenishing roller 18 in accordance with the output of the toner control sensor 21, and keeps the toner concentration in the developing device 7 constant by replenishing the toner by this driving.

Similarly, gears 27 and 28 are also provided at the rear end portions of the developing roller 20 and the agitating roller 19, and a coupling ring gear 29 that meshes with the gears 27 and 28 is provided between the gears 27 and 28. By connecting a predetermined driving source to the developing roller 20 and the stirring roller 19 at the time of development.
Are driven together. In FIGS. 4 and 5, reference numeral 30 denotes an ear-cutting plate for cutting the ears of the developer on the developing roller 20.

On the other hand, the cleaning device 8 is located on the peripheral edge of the photosensitive drum 4 downstream of the developing device 7 in the rotation direction of the photosensitive drum 4, and is a blade that scrapes off the toner remaining on the photosensitive drum 4 after transfer. In addition to the lower blade 31b, the lower blade 31b contacts the peripheral surface of the photosensitive drum 4 and guides the scraped toner to the bottom without zeroing. Further, the cleaning device 8 is a cylindrical communication part that projects laterally from the side part of the case, like the developing device 7.
An upstream portion of the recycle passage 13 is disposed below the communication portion 8a (see FIGS. 2 and 3). The communication portion 8a and the recycle passage 13 are formed by an opening 32. Communicating.

At the bottom of the cleaning device 8, a carrying-out spiral 33 for carrying out the toner removed as described above to the recycling passage 13 is provided. The front end of the carry-out spiral 33 is inserted into the communication part 8a,
Further protruding from the end of 8a, the gear is
35 are provided. The rear end protrudes outside the case of the cleaning device 8, and a gear 34 provided on this protruding portion is connected to a gear 43 provided on a 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 carried out toward the opening 32.

The transport spiral 14 in the recycling passage 13 is composed of a coil spring or the like, and has the gear 35, an intermediate gear 36 meshing with the gear 35, a screw gear 38 coaxial with the gear 37 meshing with the gear 36, and the screw gear 38. Conveyance spiral meshing with 14
The carrying-out spiral via the screw gear 39 directly connected to
It is connected to 33 and is driven to rotate together with the carry-out spiral 33 by the rotation of the photosensitive drum 4. The shape of the transport spiral 14 is set so that the transport spiral 14 transports the toner in the recycle passage 13 toward the developing device 7 by the above-mentioned rotational drive.

The end of the transport spiral 14 is located immediately before the opening 22, whereas the recycle passage 13 further extends from the opening 22 in the longitudinal direction, and a space 40 is formed in this portion. .

Next, the operation of the above device will be described. First, the unit U
Before use, the developer and the toner are sealed in the developer accommodating section 15 in the developing device 7. From this state, the seal member 16 in the direction of the arrow in FIG.
By pulling out the start agent, the start agent drops from the start agent storage section 15a to the developing roller 20 side with the supply roller 18 as a boundary,
The toner is supplied, and the toner drops onto the carry-in roller 17 from the toner storage portion 15b and is supplied. 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 through the gears 43 and 34, and the rotation of the carry-out spiral 33 is further transmitted to the gears 35, 36 and 37 and the screw gears 38 and 3.
It is transmitted to the transport spiral 14 via 9, and both the carry-out spiral 33 and the transport spiral 14 are rotationally driven according to the operation of the photosensitive drum 4.

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. This toner is carried out toward the opening 32 by the carrying-out spiral 33 which is interlocked with the photosensitive drum 4, and is sent into the recycling passage 13.

The toner sent into the recycling passage 13 is carried toward the developing device 7 by the carrying spiral 14 which is rotationally driven as described above. The toner conveyed in this manner is sent from the end of the conveying spiral 14 through the opening 22 into the communication portion 7a of the developing device 7.

On the other hand, the carry-in roller 17 and the replenishment roller 18 are timely driven in conjunction with the toner density under control of the control device 44 based on the output of the toner control sensor 21. Communication department
The toner fed into the developing device 7 is carried into the developing device 7, and the replenishing roller 18 mixes the toner carried from the carrying roller 17 and the toner supplied from the toner storage unit 15 b with the developing roller 20. Replenish.

As described above, according to this device, the communication portion 7a, which is the communication portion between the developing device 7 and the recycling passage 13, has the sealing member.
Since it is provided on the opposite side of the developer accommodating portion 15 with 16 as a boundary, before the developing device 7 is used,
The developer (starting agent and replenishing toner) therein is completely sealed by the seal member 16, and the seal member 16
It can be easily put into use just by pulling it out. Therefore, even if the unit U is tilted before the developing device 7 is used, there is no concern that the developer will flow into the cleaning device 8.

Further, in the case of the structure in which the communication portion 7a is provided in the area of the toner storage portion 15b, the recycled toner is carried in on the new toner layer stored in the toner storage portion 15b, As a result, a recycled toner layer is formed on the new toner layer, and the quality of the image suddenly deteriorates at the boundary between these layers. However, as described above, the communication portion 7a is provided as low as possible in the developing device 7, Seal part 16
When the toner is removed, the toner in the toner storage portion 15b is removed by the carry-in roller 17
If it is made to fall upward, the carry-in roller 17 facilitates the mixing of the recycled toner carried into the developing device 7 with the new toner, whereby a high-quality image can always be secured.

Further, the communication portion 7a and the carry-in roller 17 are connected to the replenishing roller 18
Since it is provided on the upstream side, the recycled toner is not directly carried into the developing roller 20 side, and there is an advantage that the paper powder and the like mixed in the recycled toner is hard to be mixed with the developer.

As described above, according to the present invention, in the image forming apparatus having the toner recycling function of returning the toner in the cleaning device to the developing device through the recycling passage, the developer opening downward in the upper part of the developing device. A storage unit is provided to close the opening with a seal member, the starter storage unit of the developer storage unit is arranged on the downstream side of the replenishment mechanism, and the toner storage unit is arranged on the upstream side of the replenishment mechanism. Since a carry-in roller for carrying recycled toner into the developing device is provided at the position, it is possible to keep both the start agent and the toner in the developer storage section in a sealed state before use. Further, this new toner can be prevented from flowing to the cleaning device side through the recycling passage. Moreover, if the seal member is removed from the state before use, the starter agent in the starter agent storage section will drop to the downstream side (development section side) of the replenishment mechanism, and the toner in the toner storage section will be carried in to the upstream side of the replenishment mechanism. Since it falls on the roller, the above-mentioned starter can be used immediately,
The new toner can be mixed well with the recycled toner carried in by the carry-in roller after the start of use, which has the effect of always ensuring a good image quality.

[Brief description of drawings]

1 is a cutaway side view of a copying machine according to an embodiment of the present invention, FIG. 2 is a cutaway plan view of a unit equipped in the copying machine, and FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a cutaway side view of the unit, and FIG. 5 is a cutaway side view of a developing device in the unit. 4 ... photosensitive drum, 7 ... developing device, 7a ... communication part,
8 ... Cleaning device, 13 ... Recycling passage, 14 ...
… Conveying spiral (conveying mechanism), 15… Developer storage,
15a ... starting agent storage section, 15b ... toner storage section, 16 ...
... Sealing member, 17 ... Carry-in roller, 18 ... Replenishing roller (replenishing mechanism), 20 ... Developing roller (developing section), 33 ... Ejecting spiral (delivering mechanism), U ... Unit.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G03G 21/10

Claims (3)

[Claims] 1. A photosensitive member and a replenishing mechanism for replenishing toner to a developer, which is disposed on the periphery of the photosensitive member as an image forming process means and is composed of toner and a carrier used in a developing section. A developing device provided inside, a cleaning device provided as an image forming process means on the periphery of the photoconductor, and a recycling passage provided between the developing device and the cleaning device to communicate the inside of both, A collecting / conveying mechanism that collects the developer contained in the cleaning device and conveys the developer toward the developing device through the recycling passage, and the toner conveyed by the collecting / conveying mechanism is carried into the developing device. In an image forming apparatus having a toner recycling function provided with a carry-in roller, the replenishing mechanism is provided in the lower portion of the developing device, and the replenishing roller is provided on the upstream side. In addition to providing the above-mentioned carry-in roller, a starter agent storage portion for opening a downwardly upward starter agent in which the toner and the carrier are mixed and a toner storage portion for storing only the toner are provided in the upper part of the developing device. Are provided side by side in the lateral direction, and a seal member that closes the opening of the developer accommodating portion to seal the inside of the developer accommodating portion, and the start agent accommodating portion is more than the replenishing roller. It is arranged in the upper part of the space on the downstream side, and the toner storing section is arranged in the upper part of the space on the upstream side of the replenishing roller.
An image forming apparatus having a toner recycling function, characterized in that the carry-in roller is located immediately below the toner storage section. 2. The recovery / conveyance system is provided in the cleaning device, and is rotatably driven to recover the toner in the cleaning device and carry out the toner to the recycling passage, and to the recycling passage. Is provided,
The image forming apparatus having a toner recycling function according to claim 1, further comprising a transport mechanism that transports toner from the cleaning device side to the developing device by being rotationally driven. 3. The image forming apparatus having a toner recycling function according to claim 1 or 2, wherein the developing device and the cleaning device are configured as a single unit.