JP2928376B2 - Image forming device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine and a non-impact printer using an electrophotographic process.

2. Description of the Related Art In the above image forming apparatus, a cleaning device for collecting toner adhered to the surface of an image carrier after transfer, a conveying screw for conveying the toner collected by the cleaning device to the outside, and a holding pipe member for holding the conveying screw Copiers and the like which have a collecting container for receiving the toner conveyed by the conveying screw are known. In this type of copier, toner adheres to the holding pipe,
In some cases, the transport screw was locked and the toner could not be transported. In such a case, a serviceman can be called, and the toner stuck in the pipe must be broken down by a driver or the like and cleaned.

For this reason, Japanese Unexamined Utility Model Publication No. 1-146261 discloses a clearance between a tip end surface of a shaft provided with a spiral fin as a transport screw and a bent discharge inner wall surface of a guide cylinder opposed thereto, and It is disclosed that a tip portion is formed in an inclined surface along a spiral fin.

JP-A-64-586 and JP-A-1-133088 disclose that the machine is stopped by detecting the load on a transport screw.

However, even if the tip shape of the screw is devised as in the former case, if the toner accumulates, the toner adheres to the inside of the guide cylinder. In the case of the latter, the load is mainly detected after the toner in the collection container is full, but when the full toner is removed, the toner sticks inside the guide cylinder. Resulting in. In order to prevent this, the load detection may be performed by reducing the difference between the normal drive load and the abnormal load, but the accuracy of the load detection must be increased,
There was a problem that it became very expensive.

An object of the present invention is to provide an image forming apparatus which solves the above-described conventional problem and can prevent toner from being fixed in a holding pipe member with a simple configuration even when a collection container is full of toner. It is an object.

Means for Solving the Problems The configuration of the present invention that achieves the above object is as follows.

A cleaning device that collects the toner adhered to the surface of the image carrier after the transfer, a transport screw that transports the toner recovered by the cleaning device to the outside, a holding pipe member that holds the transport screw, and transport by the transport screw An image forming apparatus having a collecting container for receiving the toner, wherein the holding pipe member has an open end and an intermediate portion in the gravity direction in the collecting container.

According to the configuration described above, since the opening is provided in the end portion of the holding pipe member and in the direction of gravity of the intermediate portion, the conveyed toner is collected in the collection container from the opening of the intermediate portion, and when the toner becomes full. When the conveying screw is braked from its release and the toner is removed, the original state can be restored.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a copying machine showing one embodiment of the present invention. This copier illuminates the front surface of an original 1 on a contact glass 2 with a light source, for example, a flash lamp 3 instantaneously, and simultaneously projects the entire image on the original surface onto an endless belt photoreceptor 8. It is. The non-short belt photoreceptor 8 includes a driving roller 9 and three driven rollers 10a, 10b, 10c.
And the tension spring 11. In the photoreceptor unit, each roller shaft end is supported by front and rear unit side plates (not shown). The drive motor 12 independently drives and controls the belt photoconductor 8 on the rear unit side plate.

At the start of the copying operation, first, the drive motor 12 and a main motor (not shown) rotate other units such as paper feed and cleaning, and the belt photoreceptor 8 rotates in the direction of the arrow at the same time. When the mark detection sensor 13 detects the synchronization mark provided in the above, the peripheral process devices start operating under the set timing conditions. Specifically, first, the surface of the photosensitive member is charged to a negative polarity by the charging charger 14 because the organic semiconductor OPC photosensitive member is used in this example.

On the other hand, as described above, the reflected light of the original, which has been exposed to the front surface by the light source 3 via the reflecting plate 4, is reflected by the first mirror 5, lens 6,
The light passes through the mirror 7 and is irradiated and imaged on the exposure surface of the belt photoconductor 8. Thus, an electrostatic latent image corresponding to the image of the document is formed on the surface of the photoconductor, and the latent image reaches the developing device 15 as the photoconductor 8 rotates, and at this time, the latent image is formed into a visible image by toner. Be transformed into In this way, the formed visible image is supplied with the transfer paper in the paper feeder corresponding to the paper size selected from the paper feeders 16a, 16b, 16c, and 17, and the transfer charger is provided.
The visible toner image on the photoreceptor is transferred to a transfer paper by the discharge lamp 19 and the discharge lamp 20 irradiated from the back surface. The roller 10b has a roller diameter of φ and the roller diameter is small, and uses so-called curvature separation using paper stiffness. However, separation is ensured by the separation charger 21 to enhance reliability.

The paper on which the image has been transferred is fixed through a fixing device 23 via a transport vacuum belt 22, and is discharged to a discharge tray 24a or a bin 24a of a sorter 26. The post-transfer toner remaining on the photoreceptor uniformizes the charge of the residual toner by a pre-cleaning charge 28, and then the cleaning device
29 cleans.

As shown in FIG. 2, the cleaning device 29 includes a cleaning magnet roller 30 that forms a magnetic brush with a cleaning agent 34 that slides on the belt photoreceptor 8, and a collection roller that collects toner cleaned by the cleaning magnet roller 30. A cleaning blade 32 for scraping off toner from the surface of the collection roller 31; and a toner collection coil 33 for conveying the toner scraped off by the cleaning blade 32. Transport outside.

The toner conveyed from the cleaning device 29 is conveyed to a toner collection container. In this embodiment, the toner cartridge 35 of the developing device 15 is used as the toner collecting container. As shown in FIG. 3, the developing device 15 includes a developing chamber having three developing rollers 36 and two paddle wheels 37.
38, and a toner tank 39 storing toner to be supplied to the developing chamber 38.
It is provided above.

After the toner cartridge 35 is attached to the developing device 15,
Open the shutter (not shown) and remove the toner from the toner tank.
Supplied in 39. By returning the shutter to the original position after supplying the toner, the toner cartridge 35 is in a sealed empty box state, and is used as a waste toner collecting container. As shown in FIGS. 4 and 5, the toner transport from the cleaning device 29 to the toner cartridge 35 is performed by the toner recovery coil 33 on the cleaning device 29 and the toner recovery coil 40 on the main body. This is done by screw. In this case, the toner collecting coil 33 is provided in the pipe 41 and extends from the cleaning device 29 to the toner collecting coil 40. Also,
The toner collecting coil 40 extends from the connection portion of the toner collecting coil 33 to the inside of the toner cartridge 35. At this time, the toner collecting coil 40 is initially substantially vertical, but is curved in the middle and is substantially horizontal. 35
Is inside. The toner collecting coil 40 is provided in a pipe 42 as a holding pipe member. In this case, the pipe 42 is formed of a flexible pipe so as to enable the toner collecting coil 40 to be bent. The toner recovery coil 40 is a spring having a certain spring force, and its tip reaches the tip of the pipe 42.

The toner collecting coil 40 is driven to rotate by a drive device 43 with a load detection, and conveys the toner into the toner cartridge 35. As shown in FIGS. 4 and 5, the driving device 43 includes a friction roller 44 which is drivingly connected to a main body driving source.
Rotates the rotating disk 45 by frictional force, and rotates the rotating disk 45 through a gear train 46 to collect toner.
Has rotated 40. Therefore, when a load equal to or more than a predetermined value is applied to the toner collecting coil 40 by the accumulated toner or the like, the slip occurs between the friction roller 44 and the rotating disk 45, and the rotation driving of the toner collecting coil 40 stops.

When the rotation of the toner collecting coil 40 stops, ON / OFF due to the constant rotation of the filler 47 shown in FIG. 5 is not repeated, so that the detector 48 detects that the rotation of the toner collecting coil 40 has stopped. In response to this detected signal, a message such as "Replace the toner cartridge in the machine" or "Empty the toner in the toner cartridge." Is displayed on the display of the operation unit (not shown). Will be notified.

The tip of the pipe 42 enters the toner cartridge 35, and when the toner discharged to the toner cartridge 35 becomes full, the tip of the pipe 2 accumulates, so that the rotation of the toner collecting coil 40 stops. At this time, conventionally, the toner in the pipe 42 is stuck, and the toner collection coil 40 does not rotate even when the toner in the toner cartridge is emptied.

In order to solve such a problem, the present invention takes the following measures.

As shown in FIG. 6, the distal end of the pipe 42 is provided with two openings: an opening 49 at the distal end, and a slot 50 on the gravity direction side. The size of the long hole 50 is determined by the toner collection coil.
It is set to such an extent that the toner T collected at 40 comes into contact.

In the copier thus configured, as shown in FIG. 7A, the toner T discharged from the cleaning device 29 is conveyed to the toner cartridge 35, and is initially dropped into the toner cartridge 35 from the long hole 50. And FIG. 7 (b)
When the toner T gradually accumulates and the portion of the long hole 50 is closed as shown in (2), the toner T is discharged from the opening 49 of the pipe 42.
At this time, since the load of the toner collecting coil 40 touches the toner T at the position of the long hole 50, as shown in FIG. 9, the load becomes larger than that at the time of the normal rotation of FIG. 40 has not reached the area where rotation stops.

Next, as the discharge of the toner T proceeds, as shown in FIG. 7 (c), when the toner T accumulates also at the tip of the pipe 42, the load on the toner collection coil 40 increases, and the friction roller 44 and the rotating disk 45 Slips and stops rotating. At this time, as shown in FIG. 8A, the toner recovery coil 40 contracts with the toner T.

Therefore, when the toner T in the toner cartridge 35 is replaced with an empty one, the toner T that has been applying a brake to the toner collecting coil 40 at the position of the long hole 50 disappears. Therefore, the eighth
As shown in FIG. 4B, the toner T reservoir at the tip is pushed out by the spring force of the toner collecting coil 40, and the pipe 42 automatically returns to the initial state where there is no toner T.

Thus, by providing the long hole 50, the difference between the detection area and the normal rotation can be increased. In addition, the braking action on the toner collecting coil 40 is performed by the toner T of the two openings.
Since the toner is formed by the pool, the amount of toner jam at the leading end opening 49 is reduced. Further, when the braking action of the elongated hole 50 is released, the toner T in the opening 49 is also discharged by the spring force of the toner collecting coil 40, and the toner jam can be automatically eliminated.

According to the above configuration, the present invention provides an opening in the direction of gravity between the end of the holding pipe member and the intermediate portion, so that the transported toner is collected in the collection container from the opening of the intermediate portion, and the toner is full. Then, the transport screw was subjected to a braking action from the release, and the original state could be restored simply by removing the braking action.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a copying machine showing one embodiment of the present invention, FIG. 2 is a detailed diagram of a cleaning device of FIG. 1, FIG. 3 is a detailed diagram of a developing device of FIG. 1, and FIG. FIG. 5 is a cross-sectional view of the toner conveying unit for conveying the toner, FIG. 5 is a perspective view of the toner conveying unit, FIGS. 6 (a) and (b) are a cross-sectional view and a bottom view of the holding pipe member, and FIG. ), (B) and (c) are illustrations showing the operation until the toner in the collection container is full, and FIGS. 8 (a) and (b) are illustrations showing the movement of the toner in the holding pipe member. FIG. 9 is a graph showing the displacement of the load detection of the transport screw. 8 belt photoreceptor 29 cleaning device 33,40 toner recovery coil 41,42 pipe 49 opening 50 long slot T toner

Claims (1)

(57) [Claims] A cleaning device for recovering toner adhered to the surface of the image carrier after transfer, a transport screw for transporting the toner recovered by the cleaning device to the outside,
In an image forming apparatus having a holding pipe member for holding the conveying screw and a collecting container for receiving the toner conveyed by the conveying screw, the holding pipe member has a gravity direction at an end portion and an intermediate portion in the collecting container. An image forming apparatus characterized in that its parts are open.