JP2001005277A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device constituted in such a way that the residual quantity of developer can be precisely detected even when ambient temperature is changed. SOLUTION: A magnetic permeability sensor holder 40 is provided with a magnetic permeability sensor and a resistance temperature sensor and arranged at the bottom part of the developer housing part 11 of a process cartridge 10. By the magnetic permeability sensor, the residual quantity of the developer 2 included in the housing part 11 is detected based on the change of magnetic permeability and a signal corresponding to the residual quantity of the developer 2 is transmitted to a CPU 50. By the resistance temperature sensor, the temperature of the vicinity of the magnetic permeability sensor is detected based on the change of the resistance value of a resistance element and a signal corresponding to the temperature is transmitted to the CPU 50. By the CPU 50, the signal outputted from the magnetic permeability sensor is corrected based on the signal outputted from the resistance temperature sensor and the existence of the developer 2 is judged based on the corrected signal. Then, when it is judged that the developer 2 does not exist, a prescribed warning is displayed at a liquid crystal display 90.

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 such as a printer, a copying machine, a facsimile, etc., for forming image data on a recording medium by an electrophotographic method, and more particularly to an image forming apparatus having a detachable process cartridge. Things.

[0002]

2. Description of the Related Art As an image forming apparatus for forming image data on a recording medium by an electrophotographic system, there is an image forming apparatus in which a process cartridge is configured to be detachable from a main body. The process cartridge is provided with a developer accommodating section for accommodating the developer. Here, the developer is usually
What consists of a magnetic body and resin is used. In such an image forming apparatus, the developer remaining amount detection sensor constantly detects the remaining amount of the developer contained in the developer containing portion of the process cartridge. As the developer remaining amount detection sensor, for example, a sensor utilizing a magnetic detection method for detecting the remaining amount of the developer from a change in magnetic permeability is used.

[0003] The remaining amount of the developer is generally detected before or after a certain operation, such as when a print command is issued from a user or immediately after the power is turned on. Then, the control unit of the image forming apparatus determines the presence or absence of the developer based on the signal output from the developer remaining amount detection sensor, and when there is no developer, displays a warning to the user on the display unit, The image forming operation has been stopped until the process cartridge is replaced.

[0004]

By the way, in a developer remaining amount detection sensor using a conventional magnetic detection system, a signal output from the sensor changes according to a temperature near the sensor. 2. Description of the Related Art Image forming apparatuses such as copiers, printers, and facsimile machines are used in various places and regions, and naturally have different temperature environments. Therefore, when the signal obtained from the developer remaining amount detection sensor changes according to the environmental temperature, the control unit determines that there is no developer even though the developer remains, or conversely, the developer runs out. In some cases, it is determined that the developer is present even though it has already disappeared. For this reason, the conventional image forming apparatus has a problem that the presence or absence of the developer cannot be accurately detected.

Further, in the conventional image forming apparatus, even when only a small amount of the developer remains in the developer accommodating section, the control section determines that there is the developer based on the signal output from the developer remaining amount detecting sensor. Then, an image forming operation is performed. For this reason, if the developer runs out during the image forming operation, there is a problem that the paper with the faint image or the blank paper is discharged and the recording medium is wasted. Therefore, the conventional image forming apparatus remains unsatisfactory for the user.

In order to solve the problem of fading of an image and discharge of blank paper, when a small amount of developer remains in the developer accommodating section, the control section judges that there is no developer and performs image forming operation. A control method for preventing the operation from being performed is conceivable. However, in this method, since the process cartridge is replaced even though the developer remains in the developer accommodating portion, the remaining developer cannot be used, and the developer is wasted. . For this reason, this method is also not a satisfactory solution for the user.

The present invention has been made based on the above circumstances, and has as its object to provide an image forming apparatus capable of accurately detecting the remaining amount of developer even when the environmental temperature changes. is there.

It is another object of the present invention to provide an image forming apparatus which does not waste a recording medium even when an output command is issued when the remaining amount of the developer is small.

[0009]

In order to achieve the above object, the present invention provides a developer accommodating section for accommodating a developer, and supplying the developer to an electrophotographic photosensitive member. An image forming apparatus having a developing unit for developing an electrostatic latent image formed on the electrophotographic photoreceptor, wherein a remaining amount of the developer contained in the developer containing unit is detected, and the detected remaining amount is detected. A developer remaining amount detecting unit that outputs a signal corresponding to the amount, a temperature detecting unit that detects a temperature near the developer remaining amount detecting unit, and outputs a signal corresponding to the detected temperature; The signal output from the remaining amount detection means is corrected based on the signal output from the temperature detection means, and the presence or absence of the developer is determined based on the corrected signal. Display a predetermined warning when judged It is characterized in that it comprises a control means for displaying on the stage, the.

According to another aspect of the present invention, there is provided a developer accommodating section for accommodating a developer, wherein the developer is supplied to an electrophotographic photosensitive member, and the electrophotographic photosensitive member is supplied based on image data. And a developing unit for developing the electrostatic latent image formed in the developer container, the remaining amount of the developer contained in the developer containing unit is detected, and the amount of the developer is determined according to the detected remaining amount. A developer remaining amount detection unit that outputs a signal, and when image data for one or more pages is sent,
The total required consumption of the developer required to form the image data of each page by the designated number of sheets on the recording medium is calculated, and based on the signal output from the developer remaining amount detecting means, Determining the remaining amount of the developer, comparing the total required amount with the remaining amount of the developer, and performing an image forming operation when the total required amount is equal to or less than the remaining amount of the developer; Control means for displaying a predetermined warning on the display means when the total required consumption is larger than the remaining amount of the developer.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a main part of an image forming apparatus according to a first embodiment of the present invention, and FIG. 2 is a schematic perspective view of a magnetic permeability sensor holder of the image forming apparatus.

As shown in FIGS. 1 and 2, the image forming apparatus according to the first embodiment has a process cartridge 10, a magnetic permeability sensor holder 40, a central processing unit (hereinafter referred to as a CPU) 50, and a memory. It includes a unit 60, a laser irradiation control device 70, a laser irradiation device 80, and a liquid crystal display 90 as display means.

The process cartridge 10 is also called a toner cartridge, and is configured to be detachable from the apparatus main body. Such a process cartridge 10
Includes a developer accommodating section 11 for accommodating the developer 2, a developing section 21, and a cleaning container 31. When the developer 2 runs out of the developer accommodating section 11, the process cartridge 10 needs to be replaced. Here, in the present embodiment, a developer composed of a magnetic material and a resin is used as the developer 2.

The developing section 21 has a photosensitive drum (electrophotographic photosensitive member) 26, a developing roller 27, a charging roller 28, and a developing blade 29. Here, the developing roller 27,
The charging roller 28 and the developing plate 29 correspond to a developing unit. Further, the developer accommodating section 11 is provided with a stirring means 16. When the stirring means 16 rotates in the direction of the arrow α, the developer 2
Is agitated and at the same time, the developing roller 27 in the developing section 21 is
Are supplied uniformly.

The developing roller 27 is made of an elastic member. Inside the developing roller 27, a magnet (not shown) having, for example, four magnetic poles having alternately opposite magnetism is included. The developing roller 27 rotates, but the magnet does not rotate and remains fixed. The developer 2 supplied from the developer accommodating section 11 is adhered and held on the surface of the developing roller 27 by a magnet, and is conveyed by rotating the developing roller 27 in the direction of arrow β. At this time, the height of the developer 2 held on the surface of the developing roller 27 is regulated by the developing blade 29, and a thin and uniform layer of the developer 2 is formed. The developer 2 having the predetermined height is further conveyed to a position facing the photosensitive drum 26 as the developing roller 27 rotates.

On the other hand, the charging roller 28 is
To charge the photosensitive drum 26 uniformly.
And is provided in contact with. The photosensitive drum 26 rotates in the direction of arrow γ. Then, after the surface of the photosensitive drum 26 is uniformly charged by the charging roller 28, the laser beam output from the laser irradiation device 80 passes through the optical path shown by the one-dot chain line in FIG. Irradiated.
As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 26.

A developing bias power supply (not shown) applies a developing bias in which a DC component and an AC component are superimposed to the developing roller 27. As a result, a potential difference is created between the developing roller 27 and the electrostatic latent image on the photosensitive drum 26, and the developer 2 held on the surface of the developing roller 27 transfers to the electrostatic latent image on the photosensitive drum 26. I do. Thus, the electrostatic latent image is developed to form a developed image on the photosensitive drum 26.
An image developed on the photosensitive drum 26 by the developer 2 is transferred to a recording medium by a transfer unit (not shown).

The cleaning container 31 is provided with a cleaning member 36. Such a cleaning member 3
Numeral 6 is for scraping off the residual developer on the photosensitive drum 26 and storing it in the cleaning container 31.

The magnetic permeability sensor holder 40 is provided at the bottom of the developer accommodating section 11 separately from the process cartridge 10. As shown in FIGS. 1 and 2, the magnetic permeability sensor holder 40 includes a magnetic permeability sensor 41 as a developer remaining amount detecting unit and a resistance temperature sensor 4 as a temperature detecting unit.
2 and a rotation support shaft 43. The magnetic permeability sensor 41 is provided so as to protrude from the upper surface of the magnetic permeability sensor holder 40. When the process cartridge 10 is mounted on the apparatus main body, the magnetic permeability sensor holder 40 is pushed up in the direction of the arrow δ by the pressing spring while rotating around the rotation support shaft 43, and the magnetic permeability sensor 41 is It is fitted into a recess formed in the bottom.

The magnetic permeability sensor 41 detects the volume (remaining amount) of the developer 2 contained in the developer accommodating section 11 based on a change in the magnetic permeability. And the magnetic permeability sensor 41
Sends an output voltage corresponding to the remaining amount of the developer 2 in the developer accommodating section 11 to the CPU 50. FIG. 3 shows an example of the relationship between the remaining amount of the developer 2 and the output voltage from the magnetic permeability sensor 41. Here, the graph shown in FIG. 3 is obtained while keeping the temperature near the magnetic permeability sensor 41 constant. As can be seen from FIG. 3, the output voltage of the magnetic permeability sensor 41 decreases as the remaining amount of the developer 2 decreases.

On the upper surface of the magnetic permeability sensor holder 40 and near the magnetic permeability sensor 41, a resistance temperature sensor 4
2 are provided. In the present embodiment, platinum is used as the resistance element of the resistance temperature sensor 42. The resistance temperature sensor 42 detects the temperature in the vicinity of the magnetic permeability sensor 41 based on a change in the resistance value of platinum. FIG. 4 shows an example of the relationship between the temperature near the magnetic permeability sensor 41 and the resistance value of the resistance temperature sensor 42. The resistance value R of platinum is the temperature T
In the temperature band in which the image forming apparatus is used, the temperature T and the resistance value R are in a proportional relationship as shown in FIG. That is, R = q · T + R ₀ . here,
q is a constant. R ₀ is a resistance value when T = 0 ° C., and is 50Ω in the example of FIG. In general, q,
The value of R ₀ depends on the type of the resistance element. The resistance temperature sensor 42 outputs a signal corresponding to the resistance value R (temperature T) to CP
Send to U50.

The laser irradiation device 80 irradiates the photosensitive drum 16 with a laser beam under the control of the laser irradiation control device 70. This laser beam scans substantially parallel to the rotation axis of the photosensitive drum 16. At this time, under the control of the laser irradiation control device 70, the laser light irradiates the electrostatic latent image on the photosensitive drum 16 as dots. That is, the electrostatic latent image is represented by dots. An electrostatic latent image is formed at a position on the surface of the photosensitive drum 16 where the dot is irradiated, and the developer 2 is transferred as described above.

The CPU 50 controls the laser irradiation control device 70 to execute an image forming process such as a process of forming an electrostatic latent image, and to transmit a predetermined message to a liquid crystal display 90 provided outside the image forming device. Or display. Further, the CPU 50 monitors the presence or absence of the developer 2 based on signals from the magnetic permeability sensor 41 and the resistance temperature sensor 42.

Incidentally, the output voltage of the magnetic permeability sensor 41 changes according to the temperature in the vicinity of the magnetic permeability sensor 41. FIG. 5 is a diagram illustrating an example of the relationship between the temperature near the magnetic permeability sensor 41 and the output voltage of the magnetic permeability sensor 41 when a certain amount of the developer 2 remains in the developer accommodating section 11.
As shown in FIG. 5, as the temperature near the magnetic permeability sensor 41 increases, the output voltage of the magnetic permeability sensor 41 increases. Therefore, when calculating the remaining amount of the developer 2, the CPU 50 corrects the output voltage of the magnetic permeability sensor 41 based on the signal from the resistance temperature sensor 42.
Specifically, assuming that the output voltage of the magnetic permeability sensor 41 is E, the resistance value of the resistance temperature sensor 42 is R, and the current flowing through the resistance temperature sensor 42 is I, the corrected remaining amount b of the developer 2 is b
= M (E− (R + r) · I). Here, m is a constant, and r is a correction resistance value. The output voltage E includes information on the remaining amount of the developer 2 before correction. Therefore, from the output voltage E, the magnetic permeability sensor 4
The voltage (R + r) corresponding to the temperature rise near 1
By reducing I, the output voltage E of the magnetic permeability sensor 41 is reduced.
The effect of temperature rise on the temperature can be eliminated. Therefore, the remaining amount b of the developer 2 calculated in this way
Is accurate, independent of temperature.

The reason why the correction resistance value r is taken into account when calculating the remaining amount b of the developer 2 is as follows. That is, since the magnetic permeability sensor 41 and the resistance temperature sensor 42 are completely different in structure, the magnetic permeability sensor 41 is used by using only the resistance value R obtained by the resistance temperature sensor 42 as it is.
This is because if the output voltage is corrected, an accurate value for the remaining amount of the developer 2 may not be obtained.
The correction resistance value r is determined, for example, by actually performing an experiment. However, depending on the type of the resistance temperature sensor 42, the correction resistance value r may not be necessary.

In the storage section 60, a reference amount a of the developer 2 obtained from the output voltage of the magnetic permeability sensor 41 when the developer 2 in the developer accommodating section 11 becomes empty is stored in advance. The CPU 50 compares the remaining amount b of the developer 2 obtained by correcting the output voltage from the magnetic permeability sensor 41 with the reference amount a stored in the storage unit 60. When a ≧ b, the CPU 50 determines that there is no developer 2 and causes the liquid crystal display 90 to display a predetermined warning. Here, it is theoretically impossible that a> b, but the output voltage from the magnetic permeability sensor 41 fluctuates depending on the timing at which the remaining amount b of the developer 2 is actually calculated, and based on the output voltage, The calculated remaining amount b of the developer 2 may be slightly lower than the reference amount a. Therefore, even if a> b,
It is determined that there is no developer 2.

The monitoring operation for the presence or absence of the developer 2 is generally performed before or after a certain operation such as when a print command is issued from a user or when the power of the apparatus main body is turned on. Further, the monitoring operation may be performed every time a predetermined time elapses.

Next, the operation of monitoring the presence or absence of the developer 2 in the image forming apparatus of the first embodiment will be described. FIG. 6 is a flowchart for explaining the operation of monitoring the presence or absence of the developer 2 in the image forming apparatus. Here, a case where the presence or absence of the developer 2 is monitored when a print command is issued from the user will be described.

Now, when a print command is sent from the user to the image forming apparatus, processing according to the flow of FIG. 6 is started. Upon receiving such a print command, the CPU 50 first receives the reference amount a of the developer 2 stored in the storage unit 60.
Is read (S1). Next, the CPU 50 calculates the remaining amount b of the developer 2 by correcting the output voltage from the magnetic permeability sensor 41 based on the signal from the resistance temperature sensor 42 (S
2). Thus, the remaining amount b of the developer 2 independent of the temperature near the magnetic permeability sensor 41 is obtained.

Next, the CPU 50 compares the calculated remaining amount b of the developer 2 with the reference amount a of the developer 2 stored in the storage unit 60, and determines whether or not a ≧ b. A judgment is made (S3). When a ≧ b, the CPU 50 displays, for example, a message “Replace the process cartridge 10 because there is no developer 2” on the liquid crystal display 90 (S4), and stops the execution of the image forming process. (S5). On the other hand, in step S3,
When a <b, the CPU 50 determines that the developer 2 is present. Then, the CPU 50 controls the laser irradiation control device 70 to irradiate the photosensitive drum 16 with laser light from the laser irradiation device 80 (S6). Thus, the image forming process starts.

In the image forming apparatus of the first embodiment, the CPU
Corrects the output voltage output from the magnetic permeability sensor based on the signal output from the resistance temperature sensor, and calculates the remaining amount of the developer based on the corrected output voltage, thereby reducing the environment of the apparatus. Even if the temperature changes, the remaining amount of the developer can be accurately detected. Therefore, the presence or absence of the developer is determined based on the remaining amount of the developer, and when the developer is not present, a predetermined warning is displayed on the liquid crystal display to notify the user of the exact replacement time of the process cartridge. Can be. [Second Embodiment] Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a schematic configuration diagram of a main part of the image forming apparatus according to the second embodiment.

As shown in FIG. 7, the image forming apparatus according to the second embodiment includes a process cartridge 10, a magnetic permeability sensor holder 40a, a CPU 50a, a storage unit 60a, a laser irradiation control device 70, a laser irradiation device, 80 and a liquid crystal display 90. In the image forming apparatus according to the second embodiment, those having the same functions as those of the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

The magnetic permeability sensor holder 40a has a magnetic permeability sensor 41 and a rotating shaft 43. That is, this magnetic permeability sensor holder 40a differs from that of the first embodiment in that a resistance temperature sensor is not provided.
The magnetic permeability sensor 41 detects the remaining amount of the developer 2 in the developer accommodating section 11. The relationship between the remaining amount of the developer 2 and the output voltage from the magnetic permeability sensor 41 is as shown in FIG. The output voltage from the magnetic permeability sensor 41 is
50a.

The CPU 50a includes a laser irradiation controller 70
To execute an image forming process such as a process of forming an electrostatic latent image, and to display a predetermined message on the liquid crystal display 90.

Further, at the start of the image forming process, the CPU 50a monitors the remaining amount of the developer 2 based on the output voltage from the magnetic permeability sensor 41. That is, when one or more pages of image data are sent, the CPU 50a
Calculates the total consumption of the developer 2 required to form the designated number of image data of each page on the recording medium, and based on the output voltage from the magnetic permeability sensor 41, Is obtained, and the total required consumption is compared with the remaining amount of the developer. When determining that the total required consumption is equal to or less than the remaining amount of the developer, the CPU 50a causes an image forming process to be executed.

On the other hand, if the CPU 50a determines that the total required consumption is larger than the remaining amount of the developer, the CPU 50a displays a predetermined warning on the liquid crystal display 90. Moreover, at this time, the CPU
50a calculates the necessary consumption of the developer 2 required to form the specified number of image data of the page on the recording medium sequentially for each page of image data, Then, the current remaining amount of the developer 2 at the time when the required consumption amount is calculated based on the output voltage is calculated, and the required consumption amount is compared with the current remaining amount. When the required amount of consumption is equal to or less than the current remaining amount, the image forming process is performed on the image data of the page. When the required amount of consumption is greater than the current remaining amount, the image data of the page and the image data of the page are not yet obtained. The image data of the remaining pages not formed on the recording medium is stored in the storage unit 6
Write to 0a and save.

Next, the operation of monitoring the presence or absence of the developer 2 in the image forming apparatus according to the second embodiment will be described. FIG. 8 is a flowchart for explaining the operation of monitoring the presence or absence of the developer 2 at the start of the image forming process.

When a print command is sent from the user to the image forming apparatus, processing according to the flow of FIG. 8 is started.
Here, a case will be described in which image data for a plurality of pages is transmitted and image data of each page is output to a recording medium by a predetermined number N. In general, a different number of prints can be set for each page of image data.

When receiving the print command, the CPU 50a first obtains the total number of dots D of the image to be output by the user (S11). The total number of dots D is calculated by using the number of dots D _k for each page k (k = 1, 2,..., N) and the number of prints N to obtain D = N × (D ₁ + D ₂ +.・ + D
_n ). Thereafter, the CPU 50a uses the predetermined amount of developer consumption S per dot to determine
The total required consumption amount A of the developer required in the current image forming process is calculated (S12). This total consumption A is A
= D × S.

Next, the CPU 50a operates the magnetic permeability sensor 41.
Then, the remaining amount B of the developer 2 in the developer accommodating section 11 is calculated based on the output voltage from (S13). After that, the CPU 50
a is a comparison between the total required consumption A and the remaining amount of developer B, and A>
B is determined (S14). When A ≦ B, the CPU 50a covers the total required consumption amount A of the developer 2 required for executing the current image forming process by the developer 2 remaining in the developer accommodating section 11. Judge that you can do it. Then, the laser irradiation control device 70
Is controlled to irradiate the photosensitive drum 16 with laser light from the laser irradiating device 80 (S15). Thus, the image forming process starts.

On the other hand, if A> B in step S14, CPU 50a causes liquid crystal display 90 to display a message that developer 2 is running low (S16). Next, the CPU 50a first sets k = 1 (S17), and develops the image data of each page k in order, starting with the image data of the first page, in order. It is determined whether the required consumption amount of the developer 2 can be covered by the developer 2 currently remaining in the developer storage unit 11. Specifically, CPU
50a, first, the required consumption amount A _k of the developer 2 required to output the image data of the page k by the number of prints N to the recording medium is calculated from A _k = N × D _k × S (S1).
8). Thereafter, the CPU 50a determines the remaining amount B of the developer 2 at that time based on the output voltage from the magnetic permeability sensor 41.
_k is calculated again (S19). Next, the CPU 50a
Compares the required consumption A _k with the remaining amount of developer B _k, and calculates A _k
> Determines whether a B _k (S20). A _k ≦ B _k
In the case of, the CPU 50a determines that the amount of the developer 2 necessary to output the N page image data to the recording medium is left in the developer accommodating section 11. Then, the laser irradiation control device 70 is controlled to irradiate the photosensitive drum 16 with laser light from the laser irradiation device 80.
(S21). Thus, the image forming process starts for the image data of page k. Thereafter, the CPU 50a sets k
Is incremented to k + 1 (S22), and step S1
Move to 8. Then, the same processing is performed on the next page k + 1.

On the other hand, in step S20, A _k > B
_{If k} , the CPU 50a determines that the amount of the developer 2 required to output the N page image data to the recording medium is not left in the developer accommodating section 11, and
A message "Please replace the process cartridge 10" is displayed on the liquid crystal display 90. Then, the CPU 50a converts the image data of the page k and thereafter into
It is stored in the storage unit 60a (S23). In this case, when the user replaces the process cartridge 10, the process cartridge shown in FIG.
Is executed, and when the determination in step S14 is affirmative, the image data of page k and thereafter is output.

In the image forming apparatus of the second embodiment, the CPU
When the image data of one or a plurality of pages is transmitted, the total required consumption of the developer required to form the image data of each page by the designated number of sheets on the recording medium is calculated, The remaining amount of the developer is obtained based on the output voltage from the magnetic permeability sensor, and the total required consumption is compared with the remaining amount of the developer. When the total required consumption is less than the remaining amount of the developer, the image forming process is performed. Execute. This makes it possible to determine whether or not the image forming process can be performed to the end with the developer contained in the process cartridge.
A recording medium with a faint image or a blank recording medium is not ejected during the image forming process, and wasteful consumption of the recording medium can be prevented.

When the total required consumption is larger than the remaining amount of the developer, the CPU determines whether or not the image forming process for the image data can be executed to the end for each image data of each page. By outputting image data for pages that can be processed with the remaining amount of the developer, the developer contained in the process cartridge can be used effectively to the end. The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist.

For example, in the above-described first embodiment, the case where the temperature near the magnetic permeability sensor is detected using the resistance temperature sensor has been described. However, temperature detection means other than the resistance temperature sensor may be used.

In each of the above embodiments, the case where the present invention is applied to an image forming apparatus having a detachable process cartridge has been described. The present invention is also applicable to an image forming apparatus of a type that replenishes a storage unit.

[0047]

As described above, according to the image forming apparatus of the present invention, the control means corrects the signal output from the developer remaining amount detecting means based on the signal output from the temperature detecting means, By judging the presence or absence of the developer based on the corrected signal, even if the environmental temperature of the apparatus changes,
The presence or absence of the developer can be accurately determined. For this reason, by displaying a predetermined warning on the display means when it is determined that there is no developer, it is possible to inform the user of the correct supply time of the developer or the correct replacement time of the process cartridge.

According to the image forming apparatus of the present invention, when one or a plurality of pages of image data are sent, the control means copies the image data of each page to the designated number of recording media. Calculates the total amount of developer required to form and calculates the remaining amount of developer based on the signal output from the remaining amount of developer detection means, and compares the total required amount of consumption with the remaining amount of developer. Then, when the total required consumption is equal to or less than the remaining amount of the developer, the image forming process is executed. Accordingly, it is possible to determine whether or not the image forming process can be performed to the end with the developer stored in the developer storing unit. The recording medium is not discharged as it is, and wasteful consumption of the recording medium can be prevented.

Further, when the total required consumption is larger than the remaining amount of the developer, the control means determines whether or not the image forming process for the image data can be executed to the end for each image data of each page. By outputting image data for pages that can be processed with the remaining amount of developer, especially when the image forming apparatus has a process cartridge, the developer contained in the process cartridge is effectively used to the end. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a main part of an image forming apparatus according to a first embodiment of the invention.

FIG. 2 is a schematic perspective view of a magnetic permeability sensor holder of the image forming apparatus.

FIG. 3 is a diagram illustrating an example of a relationship between a remaining amount of a developer and an output voltage from a magnetic permeability sensor.

FIG. 4 is a diagram illustrating an example of a relationship between a temperature near a magnetic permeability sensor and a resistance value of a resistance temperature sensor.

FIG. 5 is a diagram illustrating an example of a relationship between a temperature near a magnetic permeability sensor and an output voltage of the magnetic permeability sensor when a certain amount of developer remains in a developer accommodating portion;

FIG. 6 is a flowchart illustrating an operation of monitoring the presence or absence of a developer at the start of an image forming process in the image forming apparatus according to the first embodiment.

FIG. 7 is a schematic configuration diagram of a main part of an image forming apparatus according to a second embodiment.

FIG. 8 is a flowchart illustrating an operation of monitoring the presence or absence of a developer at the start of an image forming process in the image forming apparatus according to the second embodiment.

[Explanation of symbols]

2 ... developer, 10 ... process cartridge, 11 ...
A developer accommodating part, 21 ... a developing part, 31 ... a cleaning container, 40, 40a ... a magnetic permeability sensor holder, 41 ...
・ Permeability sensor, 42 ... resistance temperature sensor, 50, 50
a CPU, 60, 60a storage unit, 70 laser irradiation control device, 80 laser irradiation device, 90 liquid crystal display

Claims (4)

[Claims] A developing device for supplying the developer to an electrophotographic photosensitive member and developing an electrostatic latent image formed on the electrophotographic photosensitive member based on image data; Means for detecting the remaining amount of the developer contained in the developer accommodating section, and outputting a signal corresponding to the detected remaining amount, A temperature detecting unit that detects a temperature near the developer remaining amount detecting unit and outputs a signal corresponding to the detected temperature; and a signal output from the developer remaining amount detecting unit is output from the temperature detecting unit. Control means for correcting based on the output signal, determining whether or not the developer is present based on the corrected signal, and displaying a predetermined warning on a display means when determining that the developer is not present; It is characterized by having An image forming apparatus. 2. A developer accommodating section for accommodating a developer, and a developer for supplying the developer to an electrophotographic photosensitive member and developing an electrostatic latent image formed on the electrophotographic photosensitive member based on image data. Means for detecting the remaining amount of the developer contained in the developer accommodating section, and outputting a signal corresponding to the detected remaining amount, When one or more pages of image data are sent, the total required consumption of the developer required to form the specified number of image data of each page on the recording medium is calculated, and the The remaining amount of the developer is obtained based on a signal output from the remaining amount of the developer, and the total required amount is compared with the remaining amount of the developer. When the remaining amount is less than the remaining amount, the image forming operation Is the row, the image forming apparatus characterized by comprising a control means for displaying on the display means a predetermined warning when the total required consumption is greater than the remaining amount of the developer. 3. The image processing apparatus according to claim 1, wherein when the total required amount of consumption is larger than the remaining amount of the developer, the control unit sequentially records the image data of the page by a designated number of image data of each page. The required amount of the developer required to form the medium is calculated, and the current remaining amount of the developer at the time when the required amount is calculated based on a signal output from the developer remaining amount detecting means. The required amount of consumption is compared with the current remaining amount, and when the required amount of consumption is equal to or less than the current remaining amount, the image forming operation for the image data is executed, and the required amount of consumption is reduced. 3. The image data of the page and the image data of the remaining page not yet formed on the recording medium are written and stored in the storage means when the number is larger than the current remaining amount. Image forming apparatus. 4. The image forming apparatus according to claim 1, wherein said developer accommodating portion, said electrophotographic photosensitive member, and said developing means are provided in a process cartridge detachable from a main body.
Or the image forming apparatus according to 3.