JPH0140990B2 - - Google Patents

Description

Detailed Description of the Invention <Technical Field> The present invention uses a copying apparatus that removes the developer (toner) remaining on the surface of the photoreceptor after transferring the toner image formed on the photoreceptor onto transfer paper. This invention relates to a device that notifies the timing of inspection of the storage section for collecting waste.

<Prior Art> An electrophotographic copying apparatus has a photoreceptor 1 having a photoconductive layer formed in the shape of a drum, as shown in FIG. 1, for example.
An electrostatic latent image is formed by charging the surface of the photoreceptor 1 with a charger 2 and performing image exposure with an exposure section 3.
The electrostatic latent image is visualized as a toner image by a magnetic brush developing device 4. The toner image on the photoreceptor 1 is transferred by a transfer device 6 onto a transfer material 5 such as paper that is transported along a transport path by a transport roller, and is fixed onto the transfer material through a heat fixing roller. On the other hand, after the transfer, the photoreceptor 1 passes through a static eliminator 7 disposed opposite to remove residual charges, and a cleaning device 8 cleans the remaining developer to prepare for the next image formation. If necessary, the photoreceptor 1 is irradiated with light by a lamp 9 to make the surface condition uniform after cleaning.

The toner image formed on the surface of the photoreceptor 1 is
When transferred to transfer material such as paper, generally 60 to 80
% are transferred. Then, 20 to 40% of the toner remains and adheres to the surface of the photoreceptor 1. As a means for removing this residual toner, a web, a blade, a fur brush as shown in FIG. 1, etc. are well known.

The surface of the drum-shaped photoreceptor 1 is made of a photoconductive substance such as selenium, and does not have a large yield strength in terms of wear resistance and scratch resistance, and is a major factor in damaging the photoreceptor. It is becoming. Therefore, a web type or blade type cleaning device 8 has the advantage of being simple, small, and inexpensive, but it also cleans directly by pressing the surface of the photoreceptor 1 with mechanical pressure. Therefore, it has the disadvantage that the surface of the photoreceptor 1 is easily damaged.

The developer is composed of an iron powder carrier having an acute angle of 150 to 400 meshes and toner as a colored toner. Therefore, when an electrostatic latent image on the photoreceptor surface is visualized, not only toner but also some carrier is attached to the photoreceptor surface. When this adhered carrier is cleaned in a cleaning section, the surface of the photoreceptor 1 will be more likely to be damaged.

On the other hand, a cleaning device using a fur brush is a cleaning method that is relatively less likely to cause damage to easily damaged photoreceptors such as selenium. As shown in FIG. 1, this cleaning device using a fur brush is provided with a rotationally driven hair brush 10 in a casing 11.
0 is brought into sliding contact with the photoreceptor 1 to remove residual toner. The toner adhering to the brush 10 is scraped off by a scraping plate 12 provided after contact with the photoreceptor 1. The toner is collected into a filter bag 13 connected to the casing 11 and containing the toner by the suction force of a suction means.

If the filter bag 13 collects a certain amount of toner, it will interfere with the cleaning function. In other words, the filter bag 13 becomes clogged with toner, and the toner removed by the rotating brush 10 cannot be sucked by the suction means. For this reason, a sensor is installed inside the filter bag 13, etc., and when a certain amount of toner is collected, this is detected and the user is notified of the time for inspection, etc. to replace the filter bag 13, etc. .
With such a configuration, it is necessary to provide the filter bag 13 with a sensor. Furthermore, it is very difficult to detect whether a specified amount of toner has been collected in the filter bag, and the sensor itself tends to be complicated and very expensive.

<Objective of the Invention> An object of the present invention is to notify that a specified amount of developer (toner) is stored in a developer (toner) storage part in a cleaning device without using a sensor in the storage part.

<Example> In FIG. 1, the developing device 4 has a structure in which a developer consisting of, for example, carrier and toner is accommodated in a developer tank 41, and the developer is stirred by a stirring roller 42 or the like. Further, in the figure, reference numeral 43 denotes a developing roller that is rotationally driven to magnetically adsorb the developer and convey it to a developing area facing the photoreceptor 1. A hopper 44 for replenishing toner to the developer tank 41 is arranged above the developer tank 41 via a replenishment device 45. Further, the developer tank 41 is provided with a developer concentration detection sensor 46 that detects the mixing ratio of the developer carrier and toner in the developer tank 41 . The density detection sensor 46 detects when toner is consumed each time a copy is made and the toner density falls below a predetermined toner density, and drives the replenishing device 45 to replenish toner to the developer tank 41. . Further, when the toner is replenished and stirred by the stirring roller 42, and the toner concentration reaches a set value or more, the sensor 46 detects this and stops the toner supply.

The density detection sensor 46 detects the density by detecting a change in the volume of the developer containing toner due to toner consumption, or by detecting a change in magnetic permeability. be.

As mentioned above, the developing device 4 is generally provided with a means for keeping the concentration of the developer constant at all times, and the present invention utilizes this conventionally used means as is to improve the cleaning device 8. It is configured to notify whether the amount of developer (toner) in the filter bag 12 has reached a specified amount. This configuration will be specifically explained with reference to FIG. 2.

In FIG. 2, 20 is a control circuit that controls each copying process shown in FIG. The control circuit 20 sequentially executes a copying process according to a prestored copying process control program when a print switch (not shown) is operated, for example. During execution of this control, the concentration detection sensor 46
If it is detected that the toner concentration has decreased below a predetermined toner concentration, this signal (“H”) is sent to the control circuit 20.
Output to. Upon receiving this output, the control circuit 20 outputs a drive signal to drive the replenishing device 45 to perform toner replenishment. If the toner concentration is restored to a set value or higher by this replenishment, the sensor 46 detects this and sends this signal (“L”) to the control circuit 20. As a result, toner replenishment is stopped by the replenishing device 45, and the toner concentration of the developer is kept constant. At this time, the control circuit 20 outputs a drive signal to replenish toner, and if the toner concentration does not recover to the set level for a certain period of time (the output of the sensor 46 remains "H"), the control circuit 20 outputs a drive signal to replenish the toner. Assuming that there is no toner, the warning display lamp 21 for loading toner into the hopper 44 is driven.
At the same time, the control circuit 20 causes the storage device 22 to store "1". The stored contents of the storage device 22 are retained by a backup power source 23 even when the power of the copying machine is turned off.

When the warning indicator lamp 21 is turned on, the user knows that the hopper 44 is empty of toner, and reloads a specified amount of toner into the hopper 44. After this loading, the toner in the hopper 44 is replenished by driving the replenishing device 45, and when the concentration detection sensor 46 detects that the set concentration has been reached,
Toner supply is stopped.

The warning indicator lamp 21 may be turned off manually after toner is loaded, but it may be turned off when the sensor 46 detects the set density as described above.

Each time toner is loaded into the hopper 44 as described above, the control circuit 20 stores "1" in the storage device 22.
are added. Here, it can be easily determined experimentally whether the amount of toner contained in the filter bag 13 for collecting the developer, that is, the toner, corresponds to the number of times "m" of loading toner into the toner hopper 44.
In other words, if the amount of toner stored in the filter bag 13 is known by loading a specified amount of toner once, then at what number of times the toner stored in the filter bag 13 will reach the specified value? can be easily determined. Therefore, the control circuit 20
determines whether or not the stored data in the storage device 22 has reached "m", and if it is detected that it matches "m", lights up the maintenance/inspection time display lamp 24. By lighting the lamp 24, it is possible to know when it is time for maintenance inspection (replacement) of the filter bag 13.

<Effects of the Invention> According to the copying machine of the present invention, the developer (toner) remaining on the photoconductor is removed and collected in a storage section such as a filter bag, and a notification is given that the amount of collected developer has reached a specified amount. Therefore, the number of times the developer is replenished in the developing device is memorized, and a notification is given when this memory reaches a specified number of times, and the notification can be made using the device itself that has been used in the past, so it is very simple. It can be configured as follows, and the cost can be greatly reduced.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the internal structure of a copying machine according to the present invention, and FIG. 2 is a block diagram regarding notification control according to the present invention. 1: Photoreceptor, 4: Developing device, 41: Developing tank, 4
4: Hopper, 45: Supply device, 46: Concentration detection sensor, 20: Control circuit, 21: Warning display lamp, 22: Storage device, 23: Backup power supply,
24: Maintenance inspection time indicator lamp.

Claims (1)

[Claims] 1. After visualizing the electrostatic latent image formed on the photoreceptor as a toner image in a developing device, the toner image is transferred to a transfer paper, and the developer remaining after the transfer is removed;
In a copying apparatus equipped with a cleaning device having a storage section for collecting and storing the developer, the number of times the developer is replenished to the developing device is determined in order to notify that the amount of developer collected in the storage section has reached a specified amount. A copying apparatus that drives a notification means when a predetermined number of times is reached.