JPS60239782A - Warning device of lack of toner - Google Patents

Abstract

PURPOSE:To prevent continuation of the operation of a copying machine body in the toner supply state when the toner concentration of a developer is reduced, by turning off the toner supply operation and the operation of the copying machine body if lack of a toner is warned. CONSTITUTION:When lack of the toner is warned, a toner supply signal S1 and an operation control signal S2 are not outputted, and the toner supply operation and the operation of the copying machine body are turned off. This warning state is held until an output Q is inverted to the high level, and a supply roll, a developing roll, and a photosensitive body are not operated in this warning state because the output Q is not inverted unless an operator loads a fresh cartridge whose thin film is broken. Thus, a carrier of the developer is not stuck to the photosensitive body and a photosensitive body cleaning blade part when the toner is deficient, and the damage due to the magnetic arrier is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a toner shortage warning device that warns of a shortage of toner supplied from a toner cartridge to a developing section.

<Prior art> Conventionally, developing toner has been replenished by putting the toner from a bottle into a toner hopper installed near the developer tank, but this method tends to get dirty when the operator replenishes the toner. There are also problems such as difficulty in entering the hopper section. Therefore, a method has been developed in which the toner itself is made into a cartridge so that anyone can easily replenish the toner. FIG. 1 shows an example of cartridge formation. 1 is a developing roller, 2 is a stirring roller,
A toner hopper section 5 is provided above the stirring roller 2, and the toner cartridge 3 is placed into the hopper section. 4 is a replenishment roller of the toner hopper section 5. Incidentally, in the case of such a cartridge, a toner presence/absence detection device is required to warn the operator to replenish toner when the toner in the toner cartridge 3 runs out, and a toner detection sensor 6 is attached to the toner hopper section 5. There is. However, in the bowl shown in Fig. 1, the toner hopper section 5 is installed in the developer tank, and the toner detection sensor 6 is attached to the hopper section for replenishment, so the toner volume of the developer tank is nearly twice as large as that of the conventional one. This has the drawbacks of increasing cost and complicating the structure.

Therefore, in order to eliminate these drawbacks, as shown in FIG. A method of mounting the detection sensor 8 is being considered. In this case, only when the density detected by the toner density detection sensor 8 decreases, a toner replenishment signal is output, the replenishment roller 9 is rotated, and the toner falls from the cartridge into the developer tank, thereby keeping the toner density of the developing roller 1 constant. Supplies are carried out to maintain the condition. When the toner concentration reaches the reference level, the replenishment signal is no longer output, but even if the replenishment signal is output when the toner cartridge 7 is out of toner, naturally the toner will not be replenished. therefore,
If the toner density does not reach the standard level even if the toner replenishment signal is issued continuously for a certain period of time, it is determined that the toner cartridge 7 is out of toner, and at this time a signal is issued to warn that the cartridge is running out of toner. In the replenishment method shown in FIG. 2, the amount of toner replenished from the toner cartridge 7, that is, the amount of toner that falls into the developer tank is greater than the amount of toner used in the copy cycle.

The problem with the method shown in Figure 2 above is, once the toner shortage warning signal has been issued, at what timing should the toner warning be reset in accordance with the toner replenishment operation?
When replacing the cartridge/nozzle when the toner density is insufficient when the power is turned on, conventional methods set a timer for a certain period of time when the power is turned on, and if the toner density does not reach the standard level even after a certain period of time, a toner shortage warning is issued again. Therefore, even if the cartridge has been replaced, the copying machine main body can operate in a toner supply state from when the power is turned on until the warning is issued, and the developing roller and photoreceptor drum are rotating during that time. However, because the toner concentration is low at this time, the carrier (magnetic material) of the developing material may adhere to the photoreceptor and scratch and scratch the surface of the photoreceptor, or the magnetic carrier may adhere to the photoreceptor cleaning blade. This caused a problem in which the blade part was also damaged.

<Object of the Invention> The object of the present invention is to solve the above-mentioned problems, and to provide a toner shortage warning that can issue a toner shortage warning so that the copying machine does not operate in the toner supply state when the toner concentration is low. The goal is to provide equipment.

<Structure of the Invention> In order to achieve the above-mentioned object, the present invention includes an operation state off means for turning off the operation state of the copying machine main body when the toner is insufficient, and an operation state off means that is linked to the loading of the toner cartridge during the toner shortage state. The copying machine is characterized in that it has a release means for releasing the operation-off state of the copying machine main body.

<Embodiment> This embodiment is a case where the toner shortage warning device according to the present invention is applied to the toner replenishment system shown in FIG. 2 above.

FIG. 3 shows the main structure of the toner shortage warning device.

In the figure, IO is a replacement detection switch that detects the replacement of the toner cartridge, 11 is an R-S flip-flop that operates in reverse in response to the replacement of the toner cartridge and the generation of a warning when there is insufficient toner, and 12 is the operation of the copying machine main body. This is an LSI that performs control. LS112 outputs a toner replenishment signal S1 when the detected density of the toner detection density sensor (indicated by number 8 in FIG. 2) is below the reference level, and generates a warning signal when it is determined that there is a toner shortage state based on the detected density. Further, it outputs an operation control signal S2 for turning off the operating state of the copying machine main body at the time of a warning, and for canceling the operating state of the copying machine at the time of warning reset.

FIG. 4 shows the operating mechanism of the replacement detection switch IO. The replacement detection switch 10 is located on the side wall 1 of the cartridge loading section.
3 and is turned on by contact with the presser 16. The pressing element 16 is biased toward the outside of the side wall 13 by a slope spring 17. Toner cartridge case 1
4 is formed with a recess 18 into which the head of the presser I6 is inserted when loading the cartridge. A thin film 15 is attached to the opening of the recess 18 . When loading a new toner cartridge filled with toner into the toner supply section, the cartridge case 14 is pushed in the direction of arrow A. Then, the presser 16 presses the thin film 15
It moves in the direction of arrow A, and its rear end contacts the exchange detection switch 10, turning it on.

When the cartridge case 14 is further pushed in, the head of the presser 16 breaks through the thin film 15 and returns to its original position by the action of the leaf spring 17. When the loading of the toner cartridge is completed, the head of the presser 16 is inserted into the four parts 18.

Next, the operation of the above configuration will be explained.

In the normal operating state of the copying machine, the set input S and reset input R of the flip-flop 11 are "H" due to the hack-up power supply of the S I 12, and the output Q is "H".
”.When the toner shortage warning state occurs, the reset manual power R changes from “H” to “L” for a certain period of time, and as a result, the output Q changes from “H” to “L”.The inversion of this output Q toner replenishment signal SL and operation control signal S2
is no longer output to the drive control section (not shown) on the copying machine main body side. That is, when the toner shortage warning state occurs, the toner replenishment operation is stopped and the operation state of the copying machine main body is turned off. When the toner cartridge is replaced in this toner shortage warning state and a new toner cartridge is loaded into the toner supply section, the replacement detection switch 10 is turned on by the action of the suppressor 16 as described above, and is turned off again when loading is completed.

Therefore, the flip-flop 11 is also inverted by the on/off operation of the replacement detection switch 10, and the output Q returns to "H". As a result, the operation control signal S2 is output again from the LST 12, and the copying machine main body returns to the operation-on state. That is, by detecting cartridge replacement with the replacement detection switch 10, it is possible to reset (cancel) the operational state of the copying machine main body based on the toner shortage warning signal. As described above, the release means of the present invention is constituted by the R-S flip-flop 11 which is reversely operated by the exchange switch 10. As shown in FIG. 4, the replacement detection switch 10 is activated by moving the pusher 16, but the cartridge case 14 has a structure in which a non-renewable thin film 15 that can be broken by the pusher 16 is attached. Therefore, even if you remove the cartridge when the toner runs out and then load it again, the thin film 15 will have already been torn, and the operation off state can be reset by using the used cartridge 7 without activating the replacement detection switch 10. may be prohibited. In other words, when a new cartridge is loaded, the copying machine returns to the operating state.
To eliminate the risk of restarting toner supply due to not being reset even if an empty cartridge is loaded by mistake, and to avoid damage to a photoreceptor etc. due to lack of toner.

FIG. 5 shows specific operations of toner replenishment and toner shortage warning performed when the power is turned on.

When the power is turned on in step r+1 (hereinafter, step n+ is simply referred to as ni), it is first determined whether or not there is a warning state based on the signal level of the output Q (n2). Output Q is I
]”, the process moves to detection and judgment of toner density below 03, and when it is “L”, it is in the toner shortage warning state (n
8).

In n3, it is determined whether the detected density of the toner density detection sensor is below the reference level, and if it is below the reference level, the LS
Start the timer of I 12 (n 4. n
5). Next, there is a replenishment roller (indicated by number 9 in FIG. 2 above).

) to cause toner to fall from the toner cartridge and replenish it into the developer tank (n6). This toner supply is n
The process continues until the preset time of the timer preset in step 5 has elapsed (n7). When the toner concentration exceeds the reference level, the process proceeds from n3 to n9 to reset the timer, reset the toner shortage warning, and stop toner replenishment. If the toner density does not exceed the reference level even after the preset time has elapsed, a toner shortage warning is issued (n?, n
8).

When the toner shortage warning state occurs at step n8 above, the toner replenishment signal S1 and the operation control signal S2 are not output, and the toner replenishment operation and the operating state of the copying machine main body are turned off. This warning state is maintained until the output Q is inverted to "H". As a result, the output Q will not be reversed unless the operator loads a new cartridge in which the thin film 15 is not torn, and the replenishment roller, developing roller, and photoconductor will not operate (rotate) during the warning, so there may be a shortage of toner. In this state, the carrier of the developing material does not adhere to the photoreceptor or the photoreceptor cleaning blade, and damage caused by the magnetic carrier can be prevented.

FIG. 6 shows specific operations for toner replenishment and toner shortage warning performed at the time of copying.

When the copy button (not shown) is pressed down (n'2
0), as in the case when the power is turned on, it is determined whether or not there is a toner shortage state based on the density detected by the toner density detection sensor (n20, n21). When the toner concentration is below the standard level, the timer starts and the toner replenishment unit resets, determines whether the toner concentration exceeds the standard level, and if it exceeds the standard level, resets the timer, resets the toner shortage warning, Toner supply is stopped (n22 to n24. n26). If the toner density remains below the reference level even after the precent time has elapsed, it is determined that there is a toner shortage and a warning signal is output (
n24. n25). When this toner shortage warning is issued during copying, copy execution is stopped, so the operator loads a new toner cartridge and then turns the power back on. When the power is turned on again, the second
Based on the power-on processing shown in the figure, it is determined whether toner is to be replenished and whether there is a toner shortage warning. In n25 above, a toner shortage warning is issued even during copying, and the toner replenishment operation and the operation status of the copying machine are turned off until the warning is reset, so the toner concentration will drop in the same way as when the power is turned on. The above-mentioned n8 and n25, which lead to an extension of the life of the copying machine by preventing the main body of the copying machine from being forced to operate in the toner replenishment state when the copying machine is running, correspond to the operating state turning off means of the present invention.

<Effects of the Invention> As described above, according to the present invention, the toner replenishment operation and the operation status of the copying machine body are turned off when a toner shortage condition is warned, so that it is not possible to The main body of the copying machine is not operated in the toner supply state, thereby preventing damage to a photoreceptor etc. due to a magnetic carrier lacking toner, greatly extending the life of the copying machine, and contributing to improving the reliability of the copying machine. In addition, since the operation off state of the copier main body is reset in conjunction with cartridge loading when the toner shortage warning state is in effect, the operation off state can be reliably canceled with one-touch operations such as replacing and loading the toner cartridge. The operability of the copying machine is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a conventional toner replenishing unit in the form of a cartridge, FIG. 2 is a schematic configuration diagram of a toner replenishing unit loaded with a toner cartridge having a hopper structure, and FIG.
FIG. 4 is a structural diagram showing the operating mechanism of the replacement detection sensor 10 used in the toner shortage warning device, FIG. FIG. 6 is a flowchart for explaining the specific operation of the toner shortage warning device. 7-toner cartridge, 8-toner concentration detection sensor 10-replacement detection sensor. Applicant Sharp Corporation Agent Patent Attorney Hisao Komori No. 5 ('1 i: Jt6+1

Claims (1)

[Scope of Claims] (l) comprising a toner concentration detection sensor for detecting the toner concentration in the developing section replenished from the toner cartridge, and means for storing and adding the time during which the detected concentration of the sensor is below a predetermined level; An apparatus for determining a toner shortage state and giving a warning based on whether the total time of the storage and addition means has reached a certain time, comprising an operation state turning off means for turning off the operation state of the copying machine main body when the toner shortage state occurs; A toner shortage warning device comprising a release means for releasing an operation OFF state of a copying machine main body in conjunction with loading of a toner cartridge in a toner shortage state.