JPS60129763A - Electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To prevent defective development by detecting the presence or absence of toner in a storage case to replenish the toner, and when the number of copies is counted up on the basis of toner absence signal and reaches a previously decided number of sheets, stopping the copying operation. CONSTITUTION:An original set up on an original board 1 is formed as an electrostatic latent image on the photosensitive body 3. A toner image developed by a developing device 5 is transferred to paper by a transfer device 6. When a toner density detecting sensor 55 fitted to a developing tank of the device 5 detects a level lower than a fixed density, a toner replenishing device 56 is driven by a microcomputer 25 and toner in a toner replenish tank 1 is fed. A toner residual sensor 57 is fitted to a tank 51, and at the output of a detecting signal indicating the absence of toner, the number of copies is stored in a memory device 26. When the device 26 counts up the previously decided number of sheets, a computer 25 outputs a signal 30 for stopping the copying operation. Thus, defective development can be prevented.

Description

[Detailed Description of the Invention] Technical Field> The present invention is particularly directed to the development process in the process of electrophotography.
A device that detects development defects due to the A value in advance and stops the process operation is activated.

<Prior art> Conventionally, electrophotographic copying machines, laser printers, etc., form an electrostatic latent image of a document image or information on a recording medium, and use toner, which is a colored pigment, to visualize the latent image. It was developed using This developed toner image is then transferred onto a sheet of paper, and the sheet passes through a fixing section. It is established by I-. For example, the above-mentioned developing device stores a developer consisting of a magnetic carrier and toner in a developer tank, and performs development by bringing this developing agent into contact with the Iw image forming curve of the recording medium. Furthermore, a method of developing using a one-component magnetic toner in which the toner itself has magnetism is also widely used.

Here, in order to maintain normal development by the developing device (+m), it is necessary to detect the toner concentration in the case of a two-component thread developer. The amount of toner is delivered instead of being detected. Based on these detection signals, toner is replenished into the developing device from the supply tank to ensure normal development. In other words, two-component system In the developing device used for the developer, the toner concentration of the developer in the developing device - 1 must be kept constant at all times, otherwise the quality of the image will decrease, or if over-toner occurs, a cuffing phenomenon will occur.Therefore, In order to always control the toner concentration to be constant, a toner a summer sensor is provided within the developing device, particularly within the developing chamber, and replenishment of toner with power consumption +2 is performed in response to the output from this sensor. When the toner temperature reaches a certain level due to toner replenishment, toner replenishment is stopped and the toner density is kept constant.

In this case, if there is toner in the toner replenishment tank for toner replenishment, it is necessary to notify the user of this. Or, the user is informed by voice etc. that the toner has run out.This allows the user to replenish the toner in the toner replenishment tank or replace the toner replenishment tank with a new tank. 711) Providing a sensor to prompt toner replenishment: In order to notify users when the toner is running out, a sensor is installed in the tank to detect the presence of toner. Or toner according to the Kenzetsu display? Do io charging +H+
Although the title is good, there are times when the user does not have refillable toner on hand, or when the user does not replenish the developer because it is too late.

In this case, each time one copy is made, the toner in the developing device is
'l! 1 m, the toner density or toner strength decreases, making it impossible to obtain a high-quality copy image.

Therefore, even if a warning display urging replenishment of toner is made, there is no sense of taste, and it seems that the development failure could not be prevented.

<Object of the invention> The purpose of the invention is to prevent developing defects in the developing device.

The present invention aims to effectively prevent developing defects (without providing a detection means such as ciJ) in order to prevent developing defects.

<Embodiment> FIG. 1 is a cross-sectional view showing the internal structure of an electrophotographic copying machine according to the present invention, and FIG. 2 is a block diagram showing an example of a control circuit for preventing 4-in-1 copying according to the present invention. .

First, referring to FIG. 1, the process of an electrophotographic copying machine will be explained. In the figure, 1 is an original 417 table for placing the original once, 2 is an illumination means for illuminating the original on the original platen, and 1 is a mirror 2-2 that reflects the reflected light image from the original. ．． An optical system consisting of a lens 2-6 for forming the optical image L3゜2-4, 'L5 and '2 on a photosensitive surface; 3 is a photosensitive member which is a recording medium formed in the shape of a drum and rotated in the direction of the arrow; 4 is”-
A charger 5 uniformly charges the surface of the photoreceptor 1 before it is projected onto the photoreceptor 3 in the optical distribution system 2, and a charger 5 develops the static image formed on the photoreceptor 3 after projection. This is a developing device. The toner image on the photoconductor 3 developed by the developing device 5 is electrostatically attracted toward the electrostatic latent image on the photoconductor surface, but the toner image on the photoconductor 3 developed by the developing device 5 is electrostatically attracted to the electrostatic latent image on the photoconductor surface. 1l12e camera 6
It was transcribed by Sei'tun in J+1.

The above-mentioned paper is stored inside the cassette 7 or 8, which is installed at the top of the main body of the copying machine.
The paper is fed by the selection yA movement and is once sent to the sister roller I+. In addition to the cassette paper feed, manually fed paper is also once fed to the register roller II. This manual paper feeding is performed by opening the paper feed table 12, which is usually in an open state in the main body of the copying machine, and in response to a signal from a switch or the like that detects this, the paper feed roller 9 and IO for feeding the cassette paper are turned off. It is set to operational state. Therefore, only the manually fed paper carried by the paper feed t312 is sent to the register roller 11 via the conveyance roller 110, marked with -.

Here, the register roller 11 temporarily stops the paper that is being fed, and rotates the photoconductor 3 so that the tip i'+i of the toner image on the photoconductor 3'2 coincides with the leading edge of the paper or the transfer section.
] υj and transfer the paper to the transfer device 6? ilS. The monthly paper that has been transcribed is divided into i'
The light is separated from the photoreceptor 3 by the action of the 4il roller 13 and the like, and guided to the inspection roller 15 via the guide 14. Then, when the roller 15 is set to BiD, how many sheets of paper are delivered to the externally provided paper ejection tray 17 at 0-ra 16?

On the other hand, some toner that was not transferred onto the surface of the photoreceptor 3 remains after the transfer, and in order to gradually remove this toner and prepare for the next image formation, the photoreceptor 3 is cleaned. Head to the club. During this process, the photoconductor 3 is removed from the device 1.
8, the top and bottom of the surface of the photoreceptor are removed, and the remaining toner is efficiently cleaned by facing the next cleaning device 19. This cleaning device 19 uses a vacuum device to remove lint toner from a filter 2.
1 will be collected. After these steps, as a final step, the discharge lamp 22 faces the AL% light body 3 to form 'f4L',
Is this excluded? ■Photoconductor 3 at lamp 22
The entire surface of the tube is kept in a uniform superficial blood siege position (HabO) for the next image formation.

In the complement of the above, according to the invention, the phenomenon device 5
In order to keep the concentration of the developer constant at all times, the presence or absence of toner in the toner supply tank 51 for replenishing the toner to the device 5 is monitored, and the backbone display for toner replenishment, etc. It is carried out.

The developing device 5 contains a mixture of developer made of toner and magnetic carrier in its developer tank 52, and applies the developer to the surface of the photoreceptor 3 by magnetically attracting the developer and rotating it. (It has a magnetic flage developing roller 53 for developing in H contact.

Further, in the developing tank 52, there is provided an agitation roller 54 for agitating the toner supplied from the toner replenishing tank 51 at a rate of f+lr together with the developing roller 53 to make the toner concentration uniform. Toner '6:3 in this developer tank 52
In order to keep the concentration constant, a concentration sensor 55 is provided to detect the 1-st concentration. In other words,? When the A4 Ju sensor+1-55 detects a level below a certain toner concentration, upon receiving this signal, the microcomputer (control device) 25 that controls the copying operation starts the operation of the toner supply tank 51 as shown in FIG. A toner replenishing device 56 is driven to replenish toner to the developer tank 52. This replenishing device 56
By being driven, a certain box of toner is replenished into the developer tank 52.

Then, the replenished toner is uniformly stirred by the stirring roller 54. If the toner concentration at this time has not yet reached a certain level, the sensor 55 manually inputs the state to the control device 25. The toner replenishment of the replenishing device η56 is continued until the toner concentration reaches the specified -T level.Then, when the sensor 55 detects a certain toner level, the toner replenishment of the replenishing device 56 is performed. In this way, the toner concentration is controlled to a preset concentration.

Here, since the sensor 55 is a conventionally well-known sensor, its details will be omitted. In other words, since only the toner is consumed, the sensor 55 detects the developer in the developer tank.
'' level is lowered by 1, and this decrease is detected.

Or, if the toner is erased, the toner performance will decrease, and this will cause the developer itself to be damaged. Toner density can be easily detected by detecting a change in the weight of the developer itself using a pressure sensor.

Misfire + 1)] is the toner in the toner sleeve bleed tank 51 or no <
In order to detect 1S, the toner sleeve tank 51
A sensor 57 is provided inside. That is, the control device 2 receives a signal from the sensor 57 that detects the absence of toner in the tank 5I.
If 5 is input, the warning display lamp 27 prompts you to replenish toner.
to drive. This warning display lamp 27 is arranged on the operation panel of the main body of the copying machine and notifies the user. At the same time, from the time when it is detected that there is no toner in the tank 51, the number of copies to be made thereafter is stored in the memory device 2G as shown in FIG. This memo') R1j26 detects the presence of toner by the sensor 57, and its contents are cleared (+n = O), and from when the sensor 57 outputs the detection signal of no toner, the number of copies is accumulated and its contents are is held. Then, the storage data m of the memory device 26
When the number of copies is set in advance, m, g: I+, the control device 25 outputs a stop signal 30 for stopping the copying operation.

This makes copying impossible and prevents poor development.

Here, the copying operation is stopped until the number of copies is counted to 11 using the memory device 26 based on the toner empty detection signal from the sensor 57 that detects the presence or absence of toner in the toner supply tank 51. .

This means that even if the sensor 57 detects the absence of toner, the developing density will decrease from that point onwards and no developing defects will occur.

In other words, there is a certain amount of toner in the developer tank 52, and with this toner, even if you make several dozen copies, a sufficient image G degree can be obtained and no development defects will occur. . Therefore, the toner power 'Jiii (became 81
The number of copies n that does not cause image discoloration is set in advance, and when the take m in the memory device 26 reaches m≧i1 (1), the copying operation is stopped to effectively prevent developing defects, etc. It is prevented. In this case, while the memory device 26 is counting the number of copies, if toner is refilled to the toner supply tank 51, the output of the sensor 57 is reversed.
Memory device! The contents of f26 are cleared (m=, O), and the copying operation is no longer stopped. In this way, the sensor 57
: Until it detects no copy and copies 0 sheets from now on,
The warning display lamp 27 is driven to replenish toner, and is set to be inactive after 0 sheets have been copied.

At this time, it is also effective to make the display of the lamp 27 different from before.

The number of sheets n set in the memory device δ26 is used as a guideline, and from the time when the toner runs out, the toner concentration in the developer tank 52 will be ii! It is best to set the temperature at a level that can maintain the level above the limit level that causes image defects.

For example, the number of sheets n is l+! when the toner is constant V=4K due to copying of a 4-sheet semi-original. ! It is assumed that the number of copies per copy is such that no image defects will occur, and the number of copies will be easily calculated by taking into consideration the safety factor. It is also possible to start copying from the time when the toner concentration sensor 55 detects a lack of toner and set the number of sheets to a value that does not cause development defects.

In addition, the memory device 26 of the copying machine
When the ++ is cut, the contents are always backed up by ``ton/li! 28 etc. in order to keep the content ++ (g 4) blank.This is because when the sensor 57 detects that there is no toner While copying and memorizing this, %
Cleared based on 1llp, o F F,
``After the power is turned on, the number of copies will be sequentially memorized again. Therefore, before the copying operation is stopped, the toner density exceeds the limit for obtaining a constant image density, resulting in image defects. To prevent this, the memory device 26 is always stored in the 141d+ even when the copying machine is turned off.
? , it is effective to hack up the bank amplifier +'1tllJjI28 that supplies the signal.

FIG. 3 particularly shows the control device t1 in the block diagram of FIG.
Referring to FIG. 3, which is a flowchart showing the control procedure of step 25, the operation of the present invention will be explained in more detail in 8-1 below.

First, when the power of the copying machine is turned on, initial settings of the copying machine and the like are executed in step S1. In other words, manuscript table 1
Alternatively, if part of the optical system 2 is not in the normal position, the localization 11
Is the heat source of the fixing roller 15 driven? 1. Wait for the fixed stone roller 15 to reach 1iii4 degrees or the set crystallinity, etc., and copy! ii" 1
Controls for liii are implemented. Then, when the fixing roller I5 is set (to 1114 degrees) and the copying machine reaches the functional state, it exits step s1 and moves to step S2. 1. It is determined whether or not the sensor 57 detecting toner detects toner. In other words, the control device 25 manually outputs a signal indicating the presence of toner from the sensor 57. In step S3, the controller 25 outputs a signal indicating the presence of toner. 27 OF
F and clear take m in the memory device 26 (rn
=0), and the process moves to the next step S5. However, if it is detecting sensor 57 or 1.S-1ii;
The flil group 11 device 25 turns on the wooden frame indicator lamp 27.
, prompts the user to replenish toner, and executes the control request in S5.

” Step S5 includes, for example, not only controlling the temperature of the fixed roller 15 but also setting the number of copies to be made and copying (i.e.
It also includes control to set the copying machine to a specified mode based on the specified copy magnification.In this case, the number of copies made is displayed on the number display section, and the specified The magnification display tube is broken.

Control these! After the 19th work I, tr, S5 is removed and the process proceeds to step S6. This step S6 is to determine whether the number of images stored in the memory device 26 is m2n than the set number n (m7)), and if it is too thick, the process returns to step S2, drives the YT notification lamp 27, and executes the copying operation. Stops operation without any trouble. In other words, even if you operate the print switch to perform the initial copying operation, the control device 25 will
Ignore this and keep the copier in a stopped state.

Therefore, the toner is illuminated into the tank 51, and if the sensor 57 detects this, the warning lamp 27 is activated in step S3.
is turned off, and the data m stored in the memory device 26 is cleared (m=0).

Then, after passing step S5 and proceeding to S6, m≧11
If not, the process exits from this step S6 and proceeds to the next step S7. In the above 4>I+, even if the copying or use is made possible by the user, if the memory device 26 stores the set number of copies 11 or more, Disable the copier.

Next, in step S7, it is checked whether the print switch has been operated or not. If this print switch is not operated, the process returns to step S5 and the above-mentioned control 71) is repeated. From then on, the machine enters a standby state to start copying and waits for the print switch to be operated.

'' When the above-mentioned print switch is turned on, the process advances to step S8, whereby process control for obtaining a copy is started and executed. During this copy control, if the toner concentration sensor 55 does not manually detect a lack of toner in the control device 25 in step s9, it is determined that the toner concentration is normal and step 510
Move to. Here, toner supply from the toner supply tank 51 is stopped. That is, the driving of the toner replenishing device 56 is stopped. On the other hand, if it is detected in step S9 that there is a lack of toner in the toner concentration sensor → NO 55, the toner replenishing device 56 is activated in step S11, and toner fine assembly is executed. As a result, the current phenomenon tank 521'i
The degree of toner d is detected by the sensor 55.
'it's kept. "After the above control, step S12
When the toner replenishment tank 51 is in use, a check is made to see if there is enough toner in the toner replenishment tank 51. This is because the sensor 57 detects the presence of toner.゛) ↑ When the notification lamp 27 is turned on, 9 stones of toner are detected, the notification lamp 27 is driven (514) to indicate that the toner is empty. When the process goes to step 515 in this hy state, it is checked whether or not copying of one sheet has been completed.

At this point, if copying of one sheet has not been completed, step S8
” and repeat the control operation described above.

Now, when copying one sheet η) is completed, the process exits step S15 and proceeds to steps 5I6i, where the presence or absence of toner is checked as in step SI2. In other words, if the Y↑ notification lamp 27 is being driven, it is either the sensor 57 or the tonerf 11.
( is detected, and at 517, -11 or 11° is added to the previous information [, 0 - data 1η) of the memory device city 26, and its contents are written in the memory device box 26 ↑, 0. However,
When the mandatory notification lamp 27 is not driven, the sensor 57 detects the presence of toner, and the data 1η of the memory device 26 is cleared in step S18.

After the constraint operation described in 1Z, in step 19 the memory table 2 is
Note 6 '1) The data 1η is compared with the number n of Y sheets to be set. If S12. When the step S13 is followed, it is naturally m-〇, and the process proceeds to the next step S2O. Also, 516. Even after going through step S17, if the stored data 1n of the memory device 26 is less than the set number, the process proceeds to the next step S20 as described above, and if the stored data m of the memory device 26 is m≧ If the condition n is satisfied, the warning display lamp 27 is driven in step S2. l1ll is executed.

*]L L As mentioned above, remove Sj9 in step S2
If the value goes to 0, it is checked whether the multi-copy cycle has ended or not. That is, the number of copies to be made is set at 55 when operating the printer, and once this number of copies has been completed, the process advances to step S2 and waits for the next copying operation. However, if the set number of copies have not been made, the process returns to step S8 and starts the control operation for the next copy. After that, if all the multi-copy cycles are completed, the process returns to step S2 and waits for the next copying operation.

During the copy control operation, when the toner absence detection signal from the toner presence/absence detection sensor 57 is input to Cfz', a normal copy operation is executed, and step 5 is executed.
After going through steps 19→S2→S4, the lamp 27 is driven, and then going through steps S5→S6, the appearance step S2
→Create a route such as S4. This occurs when 1η≧n, and copy control will not start no matter how many times the print switch is operated. This continues until the toner is replenished into the tank 51 and detected by the sensor 57.

On October 1, 2017, even if the number of sheets copied so far is stored in the memory device 26, even if it is printed out during toner copy printing on day 57, the number m of sheets copied so far is stored and retained in the memory device 26,
After turning on the power source, the signal from the 2-key sensor → 57 is continuously output, and is added to the number of copies 11 in -1- for each copy, and if lη or 1η≧11 is 71 :ri is added and 27 notification lamps are lit. Moreover, when both front display lamps 27 are lit, '1tj-,'I
Even if the IM is cut off, if you don't enter the town, S2
After checking the data held in the memory device 26, the warning display lamp 27 lights up and the copying operation is not executed even if the print switch is operated.

On the other hand, if the sensor 57 detects the presence of toner due to toner replenishment, the sensor 57 detects the presence of toner by replenishing the toner.
Clear the memory take m in 6 and set Ill = 0.

As a result, the copying machine returns to the use=J function state, and performs a copying operation after operating the print switch.

Incidentally, this embodiment is exemplified in the developing device of a copying machine.
It is obvious that the present invention is not limited to this, and can be applied to a developing device of a laser printer or a developing device that develops an electrostatic image with toner. Further, although the developing device is exemplified as using a two-component developer consisting of a carrier, a -component developer (magnetic toner) may also be used. In other words, there is no magnetic toner in the developer tank.
A system in which magnetic toner is replenished from within the eJl tank can be similarly implemented by providing a sensor for detecting the presence or absence of toner in the replenishment tank. Even with this development method, even if the toner in the replenishment tank is completely exhausted, image defects will not occur even if copies are made on several dozen sheets or more (normal copies can be made, and image defects will not occur). It is a good idea to set a number of copies that will not cause the problem and stop the copying operation after copying this number of copies.

A warning to history? ), the display lamp 27 is turned on to display the message), but the display is not limited to this, and may be a sound display.

In this case, it is effective to use prestige synthesis technology to display a message such as ``Please replenish toner.'' Well, after copying n copies of the announcement display, it's 11i.''
It is good to be different from the display. It is also effective to display the lamp before copying the 11th sheet and display the lamp after copying n sheets.

Effects of the invention> The uninvented copying machine developed J-ner 4:1117
When replenishing the toner, a sensor is installed to determine whether or not there is toner in the replenishment tank, and the sensor detects the output 11:
f,i,! Even after copying a fixed number of sheets (I-i), if the output from sensor 21 is not reversed, the operation of the device 1' will be stopped, so prompt the user to replenish toner. At the same time, toner replenishment can be carried out using the 7-J trap (but damage to the inside of the device can be minimized. Development failures in the 7-J trap will not be corrected, and damage caused by the 7-J trap can be prevented.

[Brief explanation of the drawing]

Figure 1 shows the inside of the Naruko photocopying machine according to the present invention.
Figure 2 is a control flowchart for carrying out gap copying control for detecting the remaining amount of toner according to the present invention, and Figure 3 is a flowchart without showing the control procedure of Figure 2. It is. 3: Photoreceptor, 5. Developing device, 51: Toner supply tank, 52: Phenomenon 4 High, 53: Developing roller, 56: Toner supply container, 57 Toner supply sensor, 25: Control device, 26 Memory device , 27: Sound display lamp, 28
Backup power supply.

Claims (1)

[Claims] ! . In a photographic copying machine in which toner is supplied to a developing device that develops an electrostatic latent image formed on a photoreceptor in response to a signal based on a toner shortage, a container is used to supply toner. a sensor that detects the presence or absence of toner;
The comparison means compares the one-line section in which the number of copies is counted and stored from this time due to no toner signal from the sensor, the content m of the storage section, and the predetermined number 4 white n. Ill'-: An electrophotographic copying machine characterized by comprising a control means for outputting a signal when n is detected, and a means for stopping the copying operation of the copying machine by the signal output from the control means.