JPS6069666A - Toner replenishment controlling method - Google Patents

Abstract

PURPOSE:To stabilize the density of a copy which is copied continuously and has plenty of toner adhering quantities by controlling toner replenishment based on a measured value of density of a reference density piece formed on an electrostatic image forming body, and also executing auxiliary control based on original density information. CONSTITUTION:Preliminary scanning of an original is executed together with a copying start, picture quantity information is read and added by a sensor 43, and thereafter, a toner replenishing quantity is calculated. In this case, unless a toner replenishment stop signal is outputted from a control system by an image of a reference density piece 11, a toner is replenished by this calculating result, and a copying process is advanced. When the copying process is advanced and the reference density piece image comes to a density detector 16, a toner replenishment control process is started. That is to say, if the reference density piece density is lower than the lower limit value, the toner of a prescribed quantity is replenished immediately, and if the reference density piece density is higher than the lower limit value, no replenishment is executed. In this way, the density of a copy which is copied continuously and has plenty of toner adhering quantities is stabilized within a correct range.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrostatic recording device using electrophotography, such as an electronic copying machine, in which a developing device that forms an image by developing an electrostatic image with toner, The present invention relates to a toner replenishment control method for replenishing toner.

[Prior art]

In an electrostatic recording device, such as an electronic copying machine, which forms an image by developing an electrostatic image with toner, a developing device equipped with a magnetic (magnetic) roller is usually installed, and a carrier such as iron or the like is provided in the developing device. A developer containing a mixture of magnetic powder and trigonium is put in, a magnetic brush is formed on the red sear and a citro roller, and this is rotated to rub the surface of the electrostatic image carrier, causing the toner to adhere to the charged part and developing. It is carried out. Accordingly, each time development is performed, the toner in the developer decreases and the toner to gear ratio decreases, but the toner to carrier ratio in the developer is maintained within a certain appropriate range. If the toner ratio is too low, the density of the resulting image will be reduced, and if the toner ratio is too high, the image surface will become smudged and fogged, both of which are undesirable results. Therefore, it is necessary to replenish toner appropriately so as to keep the ratio of toner and carrier constant. In addition, since the amount of toner consumption changes with the product of the image plane density and area (hereinafter referred to as image guarantee) of the subject original -1- and is not constant, the above replenishment is performed according to the decrease in the toner opening in the current fq; agent. automatically controlled
You have to throw it in a seven-seater.

Conventional methods for controlling toner replenishment include a nokl! with a constant reflective optical I5 degree called a batch in the copy 4KA.
'X' Attach the eaves piece and when copying, copy the tl to the position immediately before the original, and after development, the degree of the image formed on the electrostatic image carrier is detected by the detector, and the image density is set in advance. A method is adopted in which when the amount of toner falls below a certain value, the toner replenishing device is moved manually to replenish a certain amount of toner to the developing device. FIG. 1 is a schematic diagram of a copying machine equipped with a toner replenishing device according to the above method.

The base cover IJ is attached to the tip of the Harajuku printing table 12, and the mirrors M1 to M4 scan and photograph the document surface 13.
, a moving optical system comprising lenses L and the like takes an image at a position further in front of the beginning of the document, and an electrostatic image thereof is formed on the photosensitive drum 14, which is an electrostatic image carrier. The formed electrostatic image is developed with toner by a developing device 15, and the image density is detected by a detector 16. When the output of the detector 16 exceeds a preset value due to insufficient toner and the image density decreases, toner is replenished into the developing device 15. The image that has been detected 9 times is cleaned by the cleaning device 19Vc. The image of the original is formed at 1 o'' following the reference eaves piece image, and after development the image is 21:2 at the point of transfer electrode removal.
Immediately after the quasi-trowel piece image passes, the paper C fed along the path indicated by the thin line is transferred i15, and the remaining toner is removed by the cleaning device 19.

With the toner replenishment method described above, it takes only a few steps to add an image, such as when copying a normal document (there is no problem in cases where the amount of toner adhering to each copy is small, but when printing with a large amount of images such as printed matter) When copying manuscripts, the amount of toner applied to each copy is extremely large, resulting in a delay in toner replenishment as shown in Figure 2, resulting in unstable density of the resulting copies.

FIGS. 2A and 2B are time charts showing the operation of the copying machine and the movement of the toner waste during the operation.

Diagram 2 (A) shows the tusk at each point on the horizontal axis, and which stone on the vertical axis the image of the reference eave piece PS and the copy qkJC shown by the horizontal line corresponds to. , The fact that the C line is MN to two or more 3b points indicates that the beginning, middle, and end of a poor copy of a certain length are in different processes. Figure 2 (The line nl indicates the lower limit of toner concentration, and the printer's detector is set to operate and replenish toner when the toner concentration reaches the lower limit of 1.
is the toner f in the developing device.

Assume that the toner loading at the start of the first sheet of the lighthouse for consecutively copying originals with an extremely large amount of grain is as shown in FIG. 2 (level KE of tl slightly higher than the lower limit as shown in 131).

Due to the copying operation of the first sheet, the standard eaves piece is developed (u).
An amount of toner corresponding to the level of Ll is attached.

After that, the amount of toner decreases rapidly and reaches the level of t below the limit tt+L. Because the tube is sealed, a toner shortage signal is not sent and toner replenishment is not performed.At the time of copying the second copy, the toner adhesion layer of both images of the Nord quasi-n degree piece will be commensurate with t.)
(Because the toner shortage signal is only emitted when the reference eaves image reaches the detection unit, and toner is replenished after that), the toner concentration in the first half of the document section starts at a level of t, and further decreases until f, ihk and half. Toner is replenished for the first time when the toner is loaded, but currently there is a time delay between the toner and the toner being distributed in the container, so development is essentially carried out with a lack of toner, and two sheets in a row are Once the prayer copy is missing? i↓areζ) happens. There is no problem with the 3rd photo because the toner is not enough, but after the 4th photo, there is a shortage of toner again.
The photo is turned green.

In the figure, T' indicates a small occurrence of toner-attached QL1- per copy, and indicates that even when toner C reaches the lower limit, Yc is almost maintained stably.

Known toner supply ft11. In addition to this method, there are currently f;! There is a method of detecting toner 0If of the current powder in the container and replenishing toner when the amount of toner adhesion becomes less than a predetermined value.

These methods also have the above-mentioned problems to varying degrees.

The toner 0 degree sensor is normally installed to measure the developer in the toner storage area of the developer, but when the toner reservoir K is in contact with the toner 9If of the developer θ agent and the developer Krff, In other words, the toner recording degree of the developer at the developing position does not necessarily match, and if the toner is rapidly consumed due to reasons such as a high 9 degree original, the discrepancy becomes significant. This causes the above-mentioned problem that the image 0 degrees differs between the front and rear edges of the copy.〇 [Object of the Invention] The object of the present invention is to obtain an extremely large amount of toner on each sheet. t
To provide a toner replenishment method capable of stably maintaining the amount of toner in a developing device even when obtaining copies continuously, and obtaining copies without density fluctuations.

[Examples of A, 13, and Fruit of the Invention] The above purpose is to measure the toner concentration in the developer of a copying machine or the density of a reference dark patch image formed on the U-electronic image forming body. ,
This was achieved by a toner replenishment control method that added an auxiliary control method based on original density information to a toner replenishment control method that controls toner replenishment based on the measured value 1fC.

As ordered, the amount of toner per 77 items is as follows:
On the copy C formed J mark 1 - image oil immersion and 0 degrees loan, i.e. original f1,
It is thought that it is proportional to ) of A) multiplied by the variable magnification factor ``)J
Therefore, at the start of copying (read both sides of the cloudy charge on the entire surface of the original), calculate the toner 1 corresponding to the result of the total L1, and replenish the toner accurately for each copy. However, a measuring device that scans the entire surface of each document and measures the toner density with high accuracy, and a toner replenishment tube are required. Incorporating an old-fashioned replenishment device that is capable of controlling minute quantities of light is a practical goal for photocopying machines from both a technical and cost standpoint. Actually, it scans a part of the original, reads the image of only that part, and then replenishes toner based on that information.
Practically speaking, it is preferable to perform control such that replenishment is performed by selecting one of the five levels of toner replenishment levels, or one of several preset toner replenishment levels. However, if such a simple method is used, ,→-Toner Toner?+3 Toner LJ, l:
Since the r Lx iII control is also rough, the prediction system C
11 ml between toner supply 〇 and actual toner cost U
The present invention is designed to solve these problems. This is attempted to be prevented by combining the control method of supplying toner divided by the degree of g of the toner to be fed.

The present invention can be used in combination with a control method that uses four pieces of base material, and a control method that replenishes toner by predicting the cost of toner based on information about the original artist obtained by scanning the original wave. This is intended to stabilize the toner door in the current printer. That is, in parallel with the predicted replenishment based on 4) 70 il on the image side of the original, the toner in the developing device was detected once by measuring the base wall ω degree one time, and the toner g degree in the developing device was set in advance. When the value falls below the lower limit, priority is given to the control by the above-mentioned Hara Kazue and constant zero toner replenishment is carried out. Conversely, when the current zero toner in the two containers becomes excessive, the square of original image f is If we stop replenishment based on predictions based on
The toner F try in the developing device is controlled stably and within a certain range from τ.

A method for predicting the amount of waste consumption for each situation is to develop the original without forming an electrostatic image on the electrostatic support by exposing the original to -H preliminary U1''l. It is also possible to use a method such as detecting and integrating the surface charge with a surface potential sensor, but it is also possible to use a reflective optical sensor (hereinafter simply referred to as a sensor) that combines a luminescent layer and a photoelectric element. Directly scan the original image and read the image density'vt
Practically speaking, it is most preferable to calculate

As the above-mentioned sensor, for example, one or a plurality of small sensors as shown in FIG. 3 may be used in conjunction with each other, or a rod-shaped sensor may be used. 3rd(xl(τod and 31
32 is a light emitting knob, 32 is a light source lens, 33 is a light receiving lens, and 34 is a photoelectric element that converts the amount of incident light into an electric signal. ? A tungsten lamp, a light emitting diode, an electroluminescent light bulb can be used as a photoelectric element, and a photoelectric element can be used as a photoelectric element such as a diode, a phototransistor, an f+epsilon Cado C Uno, etc.
It is possible to use a solar light source using a metal element, selenium, etc. The light emitted from the light emitting element 31 is the original 11i12.
The reflected light Li was output as an electric signal from Koden and Riko and was sent to the stone.

The above sensor detects the origin of the original tree painting.
i: A moving optical system that scans the sensor for the first time or 91i.
J5i, the other movable part of the system can be installed from the bottom of the U-mounted U-mounted document stand, and the image side of the original that will be placed on the U-mounted U-mounted U-mounted U-mounted. In a first copy machine equipped with a .theta. transport device, a so-called auto feeder, it may be attached to the document traveling section of the O1 feeder.

Figure 4 shows a rod-shaped sensor → J in the moving optical system 42 of the copying machine 41.
43 is established. The moving optical system is shown in Fig. 121, and consists of an illumination light, a slit, and a mirror stop (not shown in Fig. 3). Scan both sides of the original 460 using f and c until the end of the original is reached.
Near+4Δ is formed. To carry out the method according to the present invention using the loading amount shown in Fig. 4, the sensor 43 is moved toward the front of the copying operation at the same time as the copying is being performed, and the toner is supplemented after the copying is completed. It is also possible to perform two copies each time the optical system is moved twice, and the first time is used as a preliminary scan, and only the sensor 43 is turned on to read one position n and the second time is performed while replenishing toner. Copying may be done by going back and forth. The latter method is preferable from the point of view of toner replenishment, but with Maenagi's method, the delay in toner replenishment can be kept to just one copy.

In place of the ?-shaped sensor shown in FIG. 4, it is also possible to use one in which 1 small sensors are lined up.

The above example uses a ladle-shaped hinge or multiple sensors arranged side by side (
:,? ! 1117) Detection is performed, but when detecting an image @ hill using - small sensors, it is necessary to avoid dropping the images distributed on the document as much as possible using a limited small sensing area. For reading, it is preferable to perform the reading at t1 on the diagonal of the document or close thereto. One page of a document, such as a document that is frequently copied, is usually laid out on the basis of 1 parallel to one side of the document and 1 to 11 in the direction. Then, for example, there is a risk of performing detection with an extremely large number of errors, such as scanning the noses between the lines in sentence d.

tj's Figure 5 shows the moving optical system 54 of the same aircraft as shown in Figure 4 42.
Above, instead of the 441-shaped sensor → J-, there is a movable small sensor 53 configured to move on the rail 57 in conjunction with the moving optical system 52 in the direction of the arrow 9 perpendicular to the direction of heart motion of the work place.
This is a photocopying machine with a . The sensor 53 is the zero shift optical system 5
When 2 reaches the position C where scanning of the original ends, move the stone 5 to the pond on the rail 57. Manuscript 56 as prescribed Appendix I
rc issue '! 31ii! + When the optical system 52 is reciprocated to position C and the optical sensor 55 is moved, the optical sensor moves along the trajectory of d, and the area of the image Q of the oblique area is read.

Detection of the drawing tip may be performed during the copying operation of the movable optical system 54, as in the case of j and 4 of the equipment shown in FIG.
It may be performed in the first preliminary scan.

Figure 6 shows a movable optical system of almost the same type as Figure 5, with the end of the scan set as its home position.When copying, it is moved back and forth to position e, and then returned to the home position from position e. I was asked to take a copy of the photograph while I was leaving. The optical sensor group rotates in the 5th direction (in conjunction with the moving optical system 6, and while the moving optical system B moves from the home position to the C position, it scans the surface of the sheath part ii!). ii Read the image amount and start toner replenishment. The scanning locus becomes part f. In the t and g part of the original binding, specify the original size in advance and stop the signal.This arrangement (according to C) is completed by taking the manuscript oral history U before copying and the movement of the copying optical system. It is also possible to replace the LIJ sensor shown in Figure 6 with a fixed stop sensor like the one used in the performance shown in Figure 4, or with ua small E sensors. It can be used in the same way as U.

All of the above are examples in which sensors are attached to the 9QJJ optical system, but even in Ishihara-type copying, where the optical system is fixed and the manuscript stirrup table is moved, it is necessary to install the optical system part +, 1 + 4 sensor. In some cases, all of the above (same manuscript 1iiriC! It should be possible to detect a mouse.

FIG. 7 shows an example in which a sensor is attached to a movable member separate from the moving optical system, and the lower side of the manuscript company U table 74 is rotated via a shaft 71 by a drive source not shown in the figure. N'dJsat
A '17J lever 72 is provided, and a small sensor leaf 3 is attached to the tip thereof. Nail the ICIGC information 76 at a predetermined place on the original F5 module C table 74, and first press the lever 72.
Rotate the camera to position 11 and scan the original fA 76 from the bottom surface of the original copy table 74 using the optical sensor 73, and after detecting the image sensor of the original, position the lever. Fa
K W 1-, then the partner C1b is operated, and the area of 1 part of the hatched area of 2 Mi in the 5° figure is read, so the toner consumption area is calculated based on this, and the toner consumption is calculated in parallel with the operation of the toner. ?、■Payment is 6-ba J2.

Figure 8 shows a copying machine equipped with an auto feeder (in the example of 4:!;
) The sensor is attached to the auto feeder.

O+-74-Dach '4i '14 Q 810:)
EX document a fil table 840':) The document 86 is fed out one by one by the feed belt 82, and the predetermined value UK on the document loading table 84 is stopped by the feed belt 85FC. Be copied. When the copying is completed, the transmission belt 85 moves, the copied original is ejected, and the next original is carried into the UK at a predetermined position.

Several sensors are placed in the stirrups numbered 83 in the figure. The sensor is a rod-shaped sensor that corresponds to the document width f, or a plurality of small sensors are arranged in a direction perpendicular to the direction in which the document advances. It suffices to attach it to the removable opening J so that it returns to the original position π after the movement l-original product has passed in the direction.

Convex 'ft'1 as above. As the scanning progresses with the sensor, an average of once within the field of view of the part facing the uncoated sensor is outputted as an electric signal in time series from the seven sensors, and this is sent to the microprocessor. If the total is 1, then the scanning area of the sensor in one device is constant, so the ratio of the document area to the scanning surface 1ift is calculated based on the cumulative value. be able to. Since toner consumption is approximately proportional to the image f2 on the copy, the above value should be added to the J base for full size copying.
The toner consumption mother can be calculated by multiplying by the C constant Ice. However, for expansion, one small copy of the pig is performed ↓+A@, it is necessary to further subtract the coefficient m of the size. The above 1 (2 corresponds to the F-ner consumption U per unit area of the crosspiece image J) can be determined in terms of actual U.

1, llJ t:, the predicted toner consumption per one sheet of paper, Tc, can be determined by Tc = D @ 1 (1111 [2・m), and K to keep the toner constant at 8 degrees is −M copying. Perform the above calculation each time, and after the time required to replenish the toner of Tc, turn on the toner supply roller drive Q and seventh switch to O? B-l-two.

On the other hand, the toner replenishment control using the basic ω strip is performed as described above ν], and the electrostatic charge f is formed by forming one part of the supporting body -LK base.
Noi 1. When the Ω degree of the Ij L, base l OQ degree piece reaches the predetermined upper limit value, toner supply is stopped for each sheet of original, and when it reaches the lower limit value, toner is added. -rtL is fine. Figure 9 shows the l side of the reading judgment circuit.
In k), the toner layer 92 of the basic dark eaves formed on the electrostatic image forming member 91 is illuminated by the photodiode PD, and the reflected light is received by the phototransistor PTr. Output V from the phototransistor PTr according to the reference halftone concentration
Take out l (the higher the gJ degree, the lower it is) and comparator c,
Hey, K. Send it. The comparison voltages of comparators C1 and C2 are respectively set to 1, which corresponds to e)) transistor output when the reference piece @ penalty is the lower limit value, and 1, which corresponds to e)) transistor output when the upper limit value is A toner replenishment signal is generated when vl<vl, and C7 generates a supplementary stop signal (toner replenishment stop flag = 1) when Vl)V.
0 has been created.

The process of controlling toner replenishment 611 according to the method of the present invention will be described below with reference to a flowchart.

Figure 10 is annotation] Flownaya showing the lner capture procedure based on report 111), gi! FIG. 11 is a flowchart showing how toner is replenished based on the base wall d eave cut once.

First, a preliminary scanning line of Ma is performed with N''L start,
The sensor reads the image information and calculates the toner supplement for the 11th era. At this time, toner supply is stopped by the control system (Fig. 11) using the reference image C. If one signal is not output (toner supply stop l-nosig;
0) Predicted based on this calculation result]・-Normal supply-rC time required (T1 seconds) toner f'+il
Supplies toner by turning on the charger - evening, then 1. ;
*The first photo process below light is proceeding. When the toner replenishment stop signal is output at 11 (toner replenishment stop F, flag -1), the toner t1i supply is performed 41' and immediately Vc.
Enter the copying process.

In Mutual Pro 4, :< passes ■-rj';' When the base line formed on the charge center formation body comes to the image density reading section 1+U of FIG. 9, the flowchart of FIG. 11 appears. As shown, the replenishment is started. In other words, take the reference 0 degree angle once, take ', and if the value ρ is lower than the preset lower limit value, the toner replenishment motor is immediately turned on for T, 9, and the toner is supplied for a certain amount of time. To replenish the toner, the toner replenishing port may be set at an appropriate time in advance. The 0 degree of the stone girl eikikaden is lower than the lower limit.
If Vi<V, 'j:=)tt, toner replenishment is not performed. If the amount of toner 4 in the current machine is too large and the density of the base thread-splicing piece image is higher than the preset upper limit (vi<vt), the toner replenishment is stopped and the next copying cycle V
According to the image ft1iHIi of original *r, 1 in C...
Control it, it's 6 toners! i-pay will be suspended.

gK 12 Figure ha! *86A i Me RiM YoZ
> Prei11+I) ”)' -Mi 4t'i of toner i in the developing device when feeding is performed correctly.

It is a great way to show agriculture as a time layer. [So,
l Core (,, iV constant scanning line is scanned once by sensor υτ and detects iil!ii fj, sleeve on original dyeing) period, and connects pre-IQ > I= stand and toner replenishment. The two-point recording advance indicates that toner replenishment should be performed by the pre-scan results.

The figure shows that adjusting the toner replenishment area adds toner supplement Aia time.
It is low for the 0 go performed by the 戊.

Harane ■ is a collection of manuscripts with the middle-class 'Ro' No. 1 Miro product.
〉 Since toner is captured almost simultaneously with development, that is, toner consumption, the amount of toner in the developing device is kept almost constant during the development period, and The Tona 1st stage after the completion of the work is the same as at the beginning of the test.

Original ■ is an original with a large image storage area, and the toner consumed by development is large in i), so even if you replenish toner at the same time, the amount of toner will temporarily decrease, but the toner replenishment time will decrease. It will be extended and you will recover immediately afterwards.

For document 1 (1), when a document with a small image density is used, toner is replenished for a short time, and thereafter it is consumed little by little, returning to the starting level when the copying operation is completed.

As is clear from FIG. 12, by controlling the toner replenishment according to the method of the present invention, the toner UU at the start of the copying operation can be kept almost constant, and even when documents with large image areas are continuously copied, the toner remains constant. Since the density never goes beyond the limit density, you can obtain copies of stable quality.

In addition, excessive or insufficient toner 0 degrees is based on errors in predicted toner consumption and actual costs, such as those caused by continuous projection of originals with extremely uneven surface positions. Toner replenishment by checking the umbrella υ eaves and day IJ is too young ÷
For this reason, the toner concentration should not be out of the appropriate range and the quality of the copies should be maintained stably.

However, the information about the Hara Nekoden obtained from the sensor used in the method of the present invention can also be used simultaneously for the automatic control of the exhibition.

[Brief Description of the Drawings] Fig. 1 is a schematic diagram of a copying machine, Fig. 2 is a time chart of a conventional toner replenishment control method using a reference density strip, and Fig. 3 is a schematic diagram of an optical sensor. Figures 4 to 8 are schematic diagrams of the means for detecting the remains of an original image suitable for IJ11 in the method of the present invention. Figure 10 is a flowchart of toner replenishment control for the original fiJ I+LII envelope, and Figure 11 is a flowchart of toner replenishment control for the 5vc base of the original fiJ I+LII envelope (flowchart 1 of toner supply control).
・, 8+ (Figure 12 shows the amount of toner t1 in the current device when toner replenishment control is performed according to the method of the present invention iiA 2'J
It is a tie 12 chart indicating -. 43 + 53, 63.73.83... Sensor 44 + 54 + 64... Moving optical system 72... Rotating lever 91... i9 electric image Formation body 92...Reference spring maintenance agent Kuwabara Mu Beautiful muscle 5 figure 56 Chi figure 45 4-1 ÷0 4+ 65 concave line 6 section 610 figure

Claims (2)

[Claims] (1) In a toner replenishment control method that measures the toner concentration in the developer of an electrostatic recording device or the copy image density of a standard ephemeral strip and controls toner replenishment based on the measured value, auxiliary control based on document density information is performed. A toner replenishment control method characterized in that said toner replenishment control method is added. (2) The toner replenishment control method according to claim 1, wherein the toner replenishment by the auxiliary control is performed before the current step in the copying cycle.