JPS6316744B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control method and a control circuit for a remaining toner amount detection device for a copying machine.

Some copying machine developing units use a magnetic roller to supply toner to a cylindrical drum-shaped photoreceptor adjacent to the developing unit. This kind of developing device has a system that detects when the remaining amount of toner, especially mono-component toner, in the developing device has fallen below a certain value.
Typically, a toner remaining amount detection device is provided to notify the operator that toner needs to be replenished. The magnetic roller and one-component toner are well known to those skilled in the art, so details thereof will be omitted.

Conventionally, an element that detects the amount of single-component toner remaining in a developing device with a magnetic roller has been used to irradiate the magnetic roller with light and detect the amount of reflected light depending on the amount of toner adhering to the magnetic roller. There are reflective type photo switches that detect the amount of toner remaining, and low-actuation type micro switches that detect the amount of toner remaining by detecting the flow of toner that moves around the magnetic roller as it rotates.

In this specification, a case will be described in which the above-mentioned reflection type photo switch (hereinafter simply referred to as photo switch) is used.

Hereinafter, before describing embodiments of the present invention, a conventional method of controlling a remaining toner amount detection device will be described with reference to FIGS. 1A to 1D.

FIG. 1A shows a state in which there is sufficient toner in the developing device 2. Therefore, since there is sufficient toner on the magnetic roller 6 facing the photo switch 4, the reflected light is weak and the photo switch 4 is off, causing no toner signal (that is, the remaining amount of toner is below a certain value). signal) is not output. FIG. 1B shows a state in which the toner in the developing device 2 is consumed, the amount of toner adhering to the magnetic roller 6 decreases, the reflected light increases, and the photo switch 4 is turned on. In other words, a toner no signal occurs. FIG. 1C shows a state in which the operator opens a door (not shown) that opens and closes to replenish toner into the developing device 2. In this case, since the last magnet roller 6 is not rotating, the magnet roller 6 facing the photo switch 4
The state of toner adhesion on the top is the same as in FIG. 1B, and the remaining toner amount detection device has not been reset. In other words, the no-toner signal is still being output. FIG. 1D shows a state in which the operator manually rotates the magnetic roller 6 to spread toner over the magnetic roller 6 in order to reset the remaining toner amount detection device (ie, to turn off the photo switch). Therefore, photo switch 4
is turned off again and the remaining toner amount detection device is reset.

As mentioned above, in the conventional toner remaining amount detection device, the operator is required to perform a complicated operation of rotating the magnetic roller by hand in order to reset the device after toner is replenished.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to reliably prevent inconveniences caused by insufficient toner being sent to the detection section of the remaining toner amount detection means after toner replenishment. There is a particular thing.

The method and apparatus according to the present invention will be explained below. When the door is closed after replenishing toner, the magnetic roller rotates and the toner is transferred to the magnetic roller.
Relates to fully distributing toner to the rollers and automatically resetting the remaining toner amount detection device. That is,
According to the present invention, the reset operation, which was conventionally performed manually, can be performed automatically by simply closing the door after toner replenishment.

Hereinafter, the present invention will be explained in detail with reference to the attached FIGS. 1 to 3.

FIG. 2 is an example of a control circuit of the remaining toner amount detection device according to the present invention. In this figure, 42 is a DC power supply circuit including a transformer, a rectifier circuit, and a constant voltage circuit, and is connected to the AC power supply 38 via a power switch 40 of the copying machine. A reference voltage divided by resistors 16 and 18 is applied to the inverting input terminal 14a of the comparator 14, and a reference voltage divided by the resistors 16 and 18 is applied to the non-inverting input terminal 14b, respectively, as the light receiving element 10 of the photo switch 4 is turned on and off. A voltage higher and lower than the reference voltage is applied.

Now, in FIG. 1, assuming that the amount of toner in the developing device 2 is sufficient as shown in A, the reflection of the light emitted from the light emitting element 8 of the photo switch 4 is weak as described above. , photo switch 4 is off. Therefore, the output of the comparator 14 is a low voltage (hereinafter abbreviated as L), which is passed through an inverter 20 to an RS flip-flop (hereinafter abbreviated as FF) 2.
The voltage applied to reset terminal R of No. 2 is a high voltage (hereinafter abbreviated as H). By the way, in the state shown in FIG. 1A, the door (not shown) that opens and closes to replenish toner to the developing device 2 is closed.
Door switch 26a is on. Therefore, the voltage applied to the set terminal S of the FF 22 is L, and therefore the voltage at the output terminal Q of the FF 22 is L. A signal for rotating the magnetic roller 6 during the copying operation is applied to the terminal 32 connected to one input terminal of the OR circuit 30, but this is not directly related to the present invention.
The explanation will be given assuming that the applied voltage is L. Therefore,
The output voltage of the OR circuit 30 is L, the output voltage of the inverter 34 is H, and the relay 36 is not activated.
Note that the switch 44 controlled by the relay 36 is turned on only when the relay 36 is activated.

Next, as shown in FIG. 1B, when the toner in the developing device 2 is consumed and the photo switch 4 is turned on,
Since the voltage applied to the non-inverting input terminal 14b of the comparator 14 becomes higher than the reference voltage, the voltage at the reset terminal R of the FF 22 becomes L. On the other hand, the indicator light 24 lights up to indicate that the remaining amount of toner has fallen below a certain value. Note that the indicator light 24 is provided at a location where the operator can easily notice it, for example, where an operating section is placed. By the way, the voltage at the set terminal S of the FF 22 is L because the door switch 26a remains closed. Therefore, the output terminal Q of FF22
The voltage at is L as in the state shown in FIG. 1A, and the other door switches 26b are on, but the switch 44 is off, so the motor 46 that drives the magnetic roller 6 does not operate.

Now, when the operator opens the door to replenish toner, the switch 26a turns off and the FF22
The voltage applied to the set terminal S changes from L to H, and the voltage at the reset terminal R is L, so the voltage at the output terminal Q changes from L to H. Accordingly, the output voltage of the inverter 34 becomes L, and the relay 36
is activated and the switch 44 is turned on. However, in this case, since the door is open, door switch 26b is off and motor 46 is not activated.

When you finish toner supply and close the door, FF22
Since the voltages at the set and reset terminals S and R are both low, the voltage at the output terminal Q is in the previous state, that is, high. However, since switch 26b is closed by closing the door, motor 46 begins to operate and toner is spread over magnetic roller 6 as shown in FIG. 1D. Therefore, the output voltage of the comparator 14 becomes L, and the voltage at the reset terminal R of the FF 22 becomes H. On the other hand, since the voltage at the set terminal S is L, the voltage at the output terminal Q becomes L again. As explained previously, when the voltage at the output terminal Q is L, the relay 36 does not operate, so the switch 44
is turned off, and the motor 46, ie, the magnetic roller 6, stops rotating.

The control method and control circuit for the remaining toner amount detection device according to the present invention have been described above with reference to FIGS. 1 and 2. The above control method can be summarized as follows. That is, after detecting that the remaining amount of monocomponent toner in the developing device 2 having the magnetic roller 6 has fallen below a certain value, the operator opens the door (not shown) in order to replenish the developing device 2 with toner. The FF 22, which is a memory circuit, remembers that the door has been opened by the operation of the switch 26a of the two switches 26a and 26b that operate in conjunction with the opening and closing of the door.
Switch 26b, which is activated when the operator closes the door after replenishing toner, is activated by turning on switch 44 connected to motor 46, which is a driving means for driving magnetic roller 6, using the output signal of 44 drives the driving means and transfers the replenished toner to the magnetic roller 6.
This is a control method in which the above-mentioned detection state is canceled by sufficiently distributing the above-described detection state, and the driving of the above-mentioned driving means is stopped.

Furthermore, the control method according to the present invention will be explained based on the flowchart of FIG.

In FIG. 3, step (1): The remaining amount of toner is detected, and if it is below a certain amount, the process goes to step (2), and if it is above a certain amount, the process loops until it becomes below.

Step (2): Generate a no-toner signal (ie, a toner replenishment instruction signal) indicating that the remaining amount of toner is below a certain value.

Step (3): If the door is opened, go to step (4), otherwise loop until it is opened.

Step (4): Set FF22.

Step (5): Replenish toner.

Step (6): If you close the door, go to step (7), otherwise loop.

Step (7): Motor 46 rotations.

Step (8): If no toner signal is no longer occurring, proceed to step (9); if it is occurring, proceed to step (7).

Step (9): Stop the motor and go to step (1).

As described above, the control method and control circuit of the present invention have a remarkable feature in that the remaining toner amount detection device can be reset automatically by closing the door after toner replenishment, which conventionally was done manually. has.

In addition, in the circuit shown in Figure 2, if the door is opened when no toner signal is occurring, FF2
The voltage applied to both the set and reset terminals of 2 becomes H, and the output voltage of the output terminal Q is uncertain, but if the door is closed, the voltage of the output terminal Q is always L, so there is no fear of malfunction.

Although the embodiments of the present invention have been described above, various changes and modifications based on the above-described embodiments will be obvious to those skilled in the art. For example, the photo switch 4 can be replaced by the previously mentioned low actuation type micro switch, and the door switch 26a can be either mechanical or electronic. Furthermore, flip-flop 22 and OR circuit 30 may be replaced with other logic circuits, microcomputers, etc. having similar functionality.

The present invention relates to a method and a device for automatically moving the replenished toner to a remaining amount detection unit by closing a door after replenishing the toner, and by using this method and device, a copying operation after toner replenishment can be performed. It can be done easily.

[Brief explanation of the drawing]

1A to 1D are cross-sectional views of a developing device for explaining the prior art and the present invention, FIG. 2 is a circuit diagram showing an embodiment of the present invention, and FIG. 3 is for explaining the control method of the present invention. This is a flowchart for 2...Developer, 4...Reflective photo switch,
6...Magnetic roller, 8...Light emitting element, 1
0... Light receiving element, 14... Comparator, 22... RS
Flip flop, 24... Indicator light, 26a,
26b...Door switch, 36...Relay, 4
0...Power switch of the copying machine, 44...Switch, 46...Motor.

Claims (1)

[Scope of Claims] 1. A method for controlling a remaining toner amount detection device of a copying machine, which opens a door in response to a toner replenishment instruction signal output from the toner remaining amount detection device to replenish toner, the method comprising: toner replenishment; and then moving the toner in the developing device to a remaining toner amount detection section of the remaining toner amount detection device in response to a signal generated by closing the door. . 2. A method for controlling a remaining toner amount detection device of a copying machine, in which a door is opened in response to a toner replenishment instruction signal output from a toner remaining amount detection device to replenish toner, and the door is closed after toner replenishment. a moving means for moving the toner in the developing device to a detection section of a remaining toner amount detecting device; a driving means for driving the moving means in accordance with the operation of the switch; and a toner replenishment instruction. A remaining toner amount detecting device comprising: means for stopping the operation of the driving means when the signal is no longer generated.