JPH08220865A - Image forming device - Google Patents

Abstract

(57) [Summary] [Object] A first invention according to the present application provides an image forming apparatus capable of preventing a malfunction due to a normal fluctuation or a fluctuation at the moment and stably detecting the remaining amount of the developer. The purpose is to do. [Structure] Q ₁ output signal is input at every 20 msec timing (step ₁ to step 2), and this is 4 sec.
It continues until the end of the sampling period (step 3).
Then, when the sampling period ends, the occurrence rate of the toner-free signal, which is the ratio of the total time of the signals indicating the absence of toner among the input signals to the sampling period, is obtained (step 4), and whether the occurrence rate is 90% or more. It is determined whether or not (step 5), if it is above, it is determined that there is no toner and the toner is displayed (step 6), and if it is less than, the control is ended and the next toner remaining amount is determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with detection means for detecting the amount of developer in a developing chamber.

[0002]

2. Description of the Related Art Generally, an image forming apparatus provided with a detecting means for detecting the amount of a developer in a developing chamber of a copying machine or the like detects an induced voltage from a developing bias and detects the induced voltage and a predetermined reference voltage. There is known an image forming apparatus that detects the amount of the developer based on the above, and immediately lights up the no developer display and the developer replenishment display based on the signal.

[0003]

However, in the above-mentioned conventional example, if there is a stirring member for stirring the developer in the developing chamber, there is a problem that the detection signal of the developer fluctuates due to the movement of the developer by the stirring member. It was

That is, even if only the stirring member rotates, the induced voltage may fluctuate, and noise may be generated. Even if the display of no developer or developer replenishment is turned on for the first time, it disappears. The image forming apparatus has an unstable display, and there is a problem in that the remaining amount of the developer when there is no developer is wide.

For this reason, the reliability of the display is lowered, and the copy user cannot judge whether there is no developer or developer replenishment.
It was inconvenient.

In view of the above problems, the first invention of the present application provides an image forming apparatus capable of preventing malfunction due to normal fluctuations or instantaneous fluctuations and performing stable developer remaining amount detection. The purpose is to do.

In addition to the above-mentioned object, a second invention of the present application provides an image forming apparatus which can not only notify of the absence of the developer but also give a stable notice of the absence of the developer. Has an aim.

Further, in addition to the above objects, a third invention of the present application is an image forming apparatus capable of not only a notification of no developer, a notice of no developer, but also a developer replenishment corresponding thereto. Is intended to provide.

Further, in addition to the above-mentioned object, a fourth invention of the present application provides an image forming apparatus which can notify not only the control relating to the replenishment of the developer but also the number of transfer materials which can be copied. It is an object.

[0010]

According to the first invention of the present application, the above object is to provide a developing container for containing a developer, and a developing device for conveying the developer in the developing container to a latent image carrier. A developer carrying member, a bias power source for applying a developing bias to the developer carrying member, an antenna member arranged in the developing container so as to face the developer carrying member, and the antenna member is provided with the developing bias. In the image forming apparatus, the image forming apparatus is provided with a means for detecting the induced voltage generated and a developer remaining amount detecting means for detecting the remaining amount of the developer in the developing container from the induced voltage and a predetermined reference voltage. The developer remaining amount detecting means calculates a ratio of detecting that the remaining amount of the developer is smaller than a predetermined value in a plurality of detections performed within a predetermined detection period, and a predetermined reference value and the ratio. The result of comparing and It is accomplished by being configured to determine the remaining amount of the image agent.

According to the second invention of the present application,
The above-mentioned object is, in the above-mentioned first invention, a plurality of reference values are set to be compared with a ratio of detecting that the remaining amount of the developer is less than the reference value, and the remaining developer amount detecting means is This is achieved by setting the stepwise determination of the remaining amount of the developer based on the result of comparing a plurality of reference values with the above ratio.

Further, according to the third invention of the present application, in the above-mentioned second invention, in the second invention, the result of the determination of the remaining amount of the developer by the remaining developer amount detecting means determines the amount of the developer to be transferred to the developer carrier side. This is accomplished by having the means set to provide developer replenishment.

According to the fourth invention of the present application,
The object is to provide a means for calculating the number of transfer materials capable of image formation from the result of determination of the remaining amount of developer by the remaining developer amount detecting means in any one of the first to third inventions. To be achieved.

[0014]

According to the first invention of the present application, the developer remaining amount detecting means is configured such that the remaining amount of the developer is smaller than the predetermined value in a plurality of detections performed within the predetermined detection period. The residual amount of the developer is determined based on the result of calculating the detected ratio and comparing the ratio with a predetermined reference value. Therefore, even if the detection signal is unstable, the residual amount of the developer can be accurately determined. I do.

According to the second invention of the present application,
In the first aspect of the invention, a plurality of reference values are set to be compared with a ratio of detecting that the remaining amount of the developer is smaller than the reference value, and the developer remaining amount detecting means sets the plurality of reference values and Since the remaining amount of the developer is determined step by step based on the result of comparison with the ratio, a detailed determination is made, such as notifying that the remaining amount is low before the remaining amount of the developer is exhausted.

Further, according to the third invention of the present application, in the second invention, the replenishment of the developer to the developer carrying member side is performed based on the determination result of the remaining amount of the developer by the remaining developer amount detecting means. Therefore, a smooth image forming operation is performed.

According to the fourth invention of the present application,
In any one of the above-mentioned first to third inventions,
From the determination result of the developer remaining amount by the developer remaining amount detecting means,
Since the number of transfer materials capable of forming images is calculated, interruption due to the transfer material running out when a large number of images are formed can be prevented.

[0018]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) First, a first embodiment of the present invention will be described. FIG. 1 is a partial schematic configuration diagram of a copying machine which is an image forming apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a photosensitive drum which is a latent image carrier, and an optical system 2 is provided above the photosensitive drum 1. The optical system 2 includes a fixed document table 3, a document irradiation lamp 4, moving mirrors 5, 6, 7, a lens 8 and a fixed mirror 9. In addition, the photosensitive drum 1
An exposure duct 10 which surrounds the original image light flux irradiated from the optical system 2 to the photosensitive drum 1 and isolates it from the surroundings is provided at a position close to the upper part of the exposure duct 10. A blank exposure device 11 is provided to erase an electrostatic load on an unnecessary portion such as outside the image area. Further, a developing device 12 is provided at a lateral position of the photosensitive drum 1. Furthermore, at the position below the photosensitive drum 1,
A pair of timing rollers 13 for aligning the transfer paper sent from a paper feeding unit (not shown) with the developed powder image on the photosensitive drum 1, and the developing roller on the photosensitive drum 1. Transfer charger 1 for transferring a powder image onto a transfer paper
4 and a separation charger 15 that separates the transfer paper from the photosensitive drum 1. A conveyance belt 16 that conveys the transfer sheet to a fixing device (not shown) is provided adjacent to the separation charging device 15. Further, the conveyor belt 16
A cleaner 17 for removing the untransferred residual developer on the photoconductor drum 1 is provided above and in the lateral position of the photoconductor drum 1. Further, a pre-exposure irradiation lamp 18 for removing residual charges on the photosensitive drum 1 is provided at a position diagonally above the cleaner 17. Further, a charger 19 for uniformly charging the surface of the photoconductor drum 1 is provided at a position near the photoconductor drum 1 above.

Next, the details of the developing device 12 will be described. In the developing device 12, a toner cartridge 21 accommodating toner in a developing container 12 a is detachably arranged, and in the toner cartridge 21, the toner in the toner chamber 22 is sent to the developing chamber 20 through an opening 23. The transport member 24 is provided. In the developing chamber 20, a developing sleeve 25, which is a developer carrying member having a magnet (not shown) built therein, is rotatably disposed in the vicinity of the photosensitive drum 1. Further, inside the developing chamber 20, a stirring member 26 having a rotating shaft parallel to the rotating shaft of the developing sleeve 25.
Is arranged. The stirring member 26 has a function of stirring the toner and carrying the toner toward the developing sleeve 25. Further, a conductive antenna member 27 is arranged inside the developing chamber 20.

A bias voltage (for example, 1300) of a sine wave or a trapezoidal wave is applied to the developing sleeve 25.
V, 2000 Hz) is applied by the bias power supply 28 shown in FIG. 2, which causes an induced voltage in the antenna member 27. Since the value of the induced voltage varies depending on the amount of toner existing between the developing sleeve 25 and the antenna member 27, this antenna member 2 is used in this embodiment.
The voltage induced in No. 7 is processed by the circuit shown in FIG. 3 to detect the remaining amount of toner.

In the circuit of FIG. 3, the induced voltage generated in the antenna member 27 as described above is rectified by the diodes D ₁ and D ₂ , and the rectified signal is generated by the resistors R ₁ , R ₂ , R ₃ and the transistor Q ₂ . After the impedance conversion, the detection signal V _a is obtained by smoothing with the capacitor C ₁ , and the detection signal V _a and the reference voltage V _R are compared with _{each other} by the comparator Q ₁ to determine whether the toner residual amount is large or small. Is output.

In the apparatus of this embodiment, however, the detection signal V _a fluctuates ± 1 V in the rotation cycle of the stirring member 26 due to the movement of the toner and the rotation of the stirring member 26, as shown in FIG. Noise is ± 1V on the top. Therefore, when the voltage of the detection signal V _{a approaches} the voltage of the reference signal V _R , the output signal of the comparator Q ₁ becomes unstable.

Therefore, in this embodiment, the period for sampling the output signal of the comparator Q ₁ is determined, and the output signal is sampled at a predetermined cycle during this sampling period to calculate the occurrence rate of the toner-free signal. The generation rate is compared with a predetermined reference determination rate, and when the generation rate of the toner-free signal is high, it is determined that the toner is absent and the toner-free signal is displayed.

During this sampling period, the movement of the toner and the stirring member 2 which are one of the factors of fluctuation of the output signal of the comparator Q ₁
Since the rotation of No. 6 fluctuates in accordance with the rotation cycle of the stirring member 26, if the stirring member 26 is set to an integral multiple of one rotation time, a stable toner-free signal generation rate can be calculated.

In this embodiment, the rotation speed of the stirring member is 30r.
Since it is pm, the sampling period is set to 4 sec and the sampling period is set to 20 ms, and the reference determination rate is the detection signal V _a.
Since there is about 10% of noise jumping in, it was set at 90%.

That is, as shown in the flowchart of FIG. 5, the Q ₁ output signal is input at a timing of every 20 msec (step ₁ to step 2), and this is continued until the end of the sampling period of 4 sec (step 3). Then, when the sampling period ends, the occurrence rate of the toner-free signal, which is the ratio of the total time of the signals indicating the absence of toner among the input signals to the sampling period, is obtained (step 4), and whether the occurrence rate is 90% or more. It is determined whether or not (step 5), if it is above, it is determined that there is no toner and the toner is displayed (step 6), and if it is less than, the control is ended and the next toner remaining amount is determined.

As a result of an examination under the above conditions, it was possible to stabilize the remaining amount of toner when displaying no toner. In addition, 1
If the required number of samples cannot be obtained by copying once, the data may be stored in the memory.

(Second Embodiment) This embodiment is an example in which two reference judgment rates for comparison with the occurrence rate of the toner-less signal are set, and by doing so, the toner-less display and the toner-free notice are given. A two-stage display can be displayed.

For example, by setting the reference determination rate to 10% and 90%, the LED blinks as a toner-free advance notice display when the toner-free signal generation rate is 10% or more, and the toner-free signal generation rate is 90%. As described above, the LED is turned on to indicate that there is no toner, and the copy inhibition control is performed.

Thus, the occurrence rate of the toner-less signal is 1
With the difference between 0% and 90%, it is possible to display the toner-free notice of about 300 sheets before in the reference chart.

Further, by adding a reference judgment rate for detecting toner replenishment, it is possible to set the toner replenishment mode for judging the presence or absence of toner replenishment, displaying no toner, and canceling copy inhibition. This toner replenishment mode is a mode in which after the copying is prohibited due to the absence of toner, the developing device is operated by turning on the power to replenish the toner from the toner chamber 22 of the toner cartridge 21 into the developing chamber 20 to cancel the prohibition of copying. Is.

To determine the toner replenishment, by setting the reference determination rate to 5%, the toner replenishment is completed when the toner-free signal generation rate is 5% or less, the developing device is stopped, and the toner replenishment mode is ended. Remove the copy prohibition.

(Third Embodiment) In the above embodiment, control relating to toner replenishment is performed, but in the present embodiment, the toner remaining amount is detected from the occurrence rate of the toner no signal, and the copy can be predicted from the toner remaining amount. Calculate and display the possible number.

The number of sheets that can be copied may be calculated by estimating the remaining toner amount from the signal rate of no toner and calculating the toner consumption amount of the reference chart.

By carrying out such control, even when a large number of copies are made, it is possible to make a smooth copy.

[0037]

As described above, the first aspect of the present application
According to the invention, the developer remaining amount detecting means calculates the ratio of detecting that the remaining amount of the developer is less than the predetermined value, out of a plurality of detections performed within the predetermined detection period, and Since the remaining amount of the developer is determined based on the result of comparing the determined reference value with the ratio, the remaining amount of the developer can be accurately grasped even when the detection signal is unstable. High display without developer is now possible. It is also possible to display the state of the developer.

According to the second invention of the present application,
In the first aspect of the invention, a plurality of reference values are set to be compared with a ratio of detecting that the remaining amount of the developer is smaller than the reference value, and the developer remaining amount detecting means sets the plurality of reference values and Since the remaining amount of the developer is judged in stages based on the result of comparison with the ratio, it is possible to make a detailed judgment, such as notifying that the remaining amount is low before the remaining amount of the developer is exhausted. ,
It became possible to display them.

Further, according to the third invention of the present application, in the second invention, the replenishment of the developer to the developer carrying member side is made based on the determination result of the remaining amount of the developer by the remaining developer amount detecting means. As a result, the user can smoothly perform the image forming operation.

According to the fourth invention of the present application,
In any one of the above-mentioned first to third inventions,
From the determination result of the developer remaining amount by the developer remaining amount detecting means,
Since the number of transfer materials capable of forming an image is calculated, it is possible to prevent interruption due to the transfer material running out when a large number of images are formed.

[Brief description of drawings]

FIG. 1 is a partial schematic view of a copying machine according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an induced voltage generated in the antenna member according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a circuit for processing the induced voltage of FIG.

4 is a diagram showing signals processed in the circuit of FIG. 3. FIG.

FIG. 5 is a flowchart illustrating a toner remaining amount determination method according to the first embodiment of this invention.

[Explanation of reference numerals] 1 photosensitive drum (latent image bearing member) 12 developing device 12a developing container 25 developing sleeve (developer bearing member) 27 antenna member 28 bias power source

Claims (4)

[Claims] 1. A developing container for accommodating a developer, a developer carrier for conveying the developer in the developer container to a latent image carrier, and a bias power source for applying a developing bias to the developer carrier. An antenna member arranged in the developer container so as to face the developer carrying member, a means for detecting an induced voltage generated in the antenna member by the developing bias, and the induced voltage and a predetermined reference voltage. In the image forming apparatus provided with the developer remaining amount detecting means for detecting the remaining amount of the developer in the developing container from the above, the developer remaining amount detecting means is provided in a plurality of detections performed within a predetermined detection period. ,
It is set to judge the remaining amount of developer by calculating the ratio of detecting that the remaining amount of developer is less than a predetermined value and comparing the ratio with a predetermined reference value. An image forming apparatus characterized by the above. 2. A plurality of reference values are set to be compared with a rate of detecting that the remaining amount of the developer is smaller than the reference value. The image forming apparatus according to claim 1, wherein the image forming apparatus is set so as to judge the remaining amount of the developer stepwise based on the result of comparison with the ratio. 3. The method according to claim 2, further comprising means set to replenish the developer to the developer carrying member side based on a result of the determination of the remaining amount of the developer by the remaining developer amount detecting means. Image forming apparatus. 4. The method according to claim 1, further comprising means for calculating the number of transfer materials on which an image can be formed, based on the result of determination of the remaining amount of developer by the remaining developer amount detecting means. Image forming apparatus.