JPH10161414A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image performing device performing two kinds of detection such as the existence of toner at the inside of a toner cartridge and the existence of the toner cartridge by using one sensor for magnetic toner. SOLUTION: As for the image forming device of an electrophotographic system where an image is formed by using the magnetic toner, the sensor 3 for the magnetic toner detecting the existence of the toner at the inside of the toner cartridge 1, a conductive member 10 covering the sensor surface of the sensor 3 for the magnetic toner when the toner cartridge 1 is not attached and retreating from the sensor surface when it is attached and a toner stirring member 2 arranged at the inside of the toner cartridge 1 facing to the sensor surface of the sensor 3 for the magnetic toner are provided, and at least the part of the toner stirring member 2 facing to the sensor surface is constituted of a nonconductive member 9, and the existence of the toner and the existence of the toner cartridge 1 are detected by the detected output of the sensor 3 for the magnetic toner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a facsimile, and a printer.

[0002]

2. Description of the Related Art An electrostatic latent image exposed on a photoreceptor by a laser beam or the like is developed into a visible image by developing with a toner supplied from a toner cartridge, and the developed toner image is transferred to a transfer material such as transfer paper. 2. Description of the Related Art An electrophotographic image forming apparatus that forms an image by transferring and fixing an image on a sheet is known. In such an image forming apparatus, a toner sensor is provided in the toner cartridge, the presence or absence of toner is determined based on the state of the detection output of the toner sensor, and the time for replacing the toner cartridge can be accurately displayed. (For example, an image recording apparatus described in JP-A-7-72730). In addition, the image forming apparatus is provided with a sensor for detecting the presence or absence of the toner cartridge when the toner cartridge is attached or detached at the time of replacement, thereby preventing the toner cartridge from being forgotten or an erroneous attachment.

[0003]

Conventionally, it has been important to reduce the cost of an electrophotographic image forming apparatus which is relatively small and inexpensive, and the developing device is integrated with a developing unit and a toner storage unit. Cartridge type (in this case, the developing device is referred to as a toner cartridge), or a cartridge type (image forming cartridge) in which the photosensitive member, the developing device, the cleaning device, and the like are integrated. Replacement was facilitated, recycling was possible, and cost was reduced. However, as described above, providing two types of sensors in the image forming apparatus, that is, a toner sensor for detecting the presence or absence of toner in the toner cartridge and a sensor for detecting the presence or absence of the toner cartridge, hinders cost reduction. Was.

[0004] The present invention has been made in view of the above circumstances, and the objects of each claim are as follows. An object of the present invention is to develop an electrostatic latent image formed on an electrostatic latent image holding member with a magnetic toner supplied from a toner cartridge to visualize the electrostatic latent image, and then transfer the toner image to a transfer material. In an electrophotographic image forming apparatus that forms an image by using a single magnetic toner sensor, two types of detection, that is, the presence or absence of toner in a toner cartridge and the presence or absence of a toner cartridge are detected.

A second object of the present invention is to develop an electrostatic latent image formed on an electrostatic latent image holding member with a magnetic toner supplied from a toner cartridge to visualize the image, and then transfer the toner image. 2. An electrophotographic image forming apparatus which forms an image by transferring an image to a material, wherein two types of detection, that is, presence / absence of a toner in a toner cartridge and presence / absence of a toner cartridge, are performed by one magnetic toner with a configuration smaller than that of claim 1. That is, detection using a sensor.

[0006]

According to an aspect of the present invention, there is provided an image forming apparatus, comprising: a magnetic toner sensor for detecting presence or absence of toner in a toner cartridge; A conductive member (10) that covers the sensor surface of the magnetic toner sensor (3) when (1) is not mounted, and retracts from the sensor surface when mounted, and a magnetic toner sensor (3). A toner stirring member (2) in the toner cartridge (1) facing the sensor surface, wherein at least a portion of the toner stirring member (2) facing the sensor surface is formed of a non-conductive member (9); The configuration is such that the presence or absence of toner and the presence or absence of a toner cartridge are detected based on the state of the detection output of the magnetic toner sensor (3) (FIG. 2).

In the image forming apparatus according to the present invention, a magnetic toner sensor (3) for detecting the presence or absence of toner in the toner cartridge (1), and the magnetic toner sensor (3)
A toner agitating member (2) in the toner cartridge (1) facing the sensor surface of (1), wherein at least a portion of the toner agitating member (2) facing the sensor surface is formed of a conductive member (11); Magnetic toner sensor (3)
, The presence / absence of toner and the presence / absence of toner cartridge are detected based on the state of the detection output (FIG. 3).

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a schematic diagram showing an example of an electrophotographic image forming apparatus according to the present invention. In the image forming apparatus shown in FIG. 1, a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as a photosensitive member) 5 formed by applying a photoconductive layer on a conductive substrate is used as an electrostatic latent image holding member. Around the photosensitive member 5, a charging device 8 for forming an image by electrophotography, a light writing device (not shown) using a laser beam, a developing device 1, A transfer roller 6, a cleaning device 7, and the like are provided.

When the image forming operation is started, first, the photosensitive member 5 is uniformly charged by the charging device 8, and then a laser beam is exposed by the optical writing device to form an electrostatic latent image on the photosensitive member 5. The electrostatic latent image is stored in the toner storage unit 1 of the developing device 1.
The image is visualized by the magnetic toner (hereinafter, toner) supplied from A to the developing roller 4 of the developing unit 1B. Next, the toner image formed on the photoreceptor 5 is transferred to transfer paper (not shown) by the transfer roller 6, and the toner image is fixed on the transfer paper by a fixing device (not shown). The transfer residual toner on the photoconductor 5 is cleaned and removed by the cleaning device 7, and the photoconductor 5 is repeatedly used for image formation.

In the configuration example shown in FIG. 1, the developing device 1 is of a cartridge type in which a developing unit 1B provided with a developing roller 4 and a toner storage unit 1A storing toner are integrated (hereinafter, referred to as a developing unit). , The developing device is referred to as a toner cartridge), and the toner cartridge 1 is detachably provided to the image forming apparatus main body. Toner cartridge 1
A toner stirring member 2 is provided in the toner storage section 1A, and the toner in the toner storage section 1A is stirred by the toner stirring member 2 and supplied to the developing roller 4 of the developing section 1B. A magnetic toner sensor 3 for detecting the presence or absence of toner in the toner cartridge 1 is provided below the toner storage section 1A of the toner cartridge 1. This magnetic toner sensor 3 is installed on the image forming apparatus main body side. I have. In addition, as a configuration of the developing device 1, the developing unit 1B and the toner storage unit 1A may be configured separately (for example, a partition is provided in a broken line portion in the figure, and the developing unit 1B and the toner storage unit 1A are provided).
In this case, only the toner storage section 1A is detachable, and the detachable toner storage section 1A is a toner cartridge.

Conventionally, a sensor for detecting the presence or absence of the toner cartridge 1 has been provided separately from the magnetic toner sensor 3 in the image forming apparatus main body when the toner cartridge 1 is attached or detached. 3, the presence or absence of the toner and the presence or absence of the toner cartridge 1 can be independently detected based on the detection output. Hereinafter, examples of the present invention will be described.

[0013]

【Example】

(Embodiment 1) FIG. 2 is an explanatory view of a main configuration of an image forming apparatus according to a first embodiment of the present invention. In the image forming apparatus of the present embodiment, in addition to the configuration of FIG. 1, when the toner cartridge 1 is not mounted at a predetermined position of the apparatus main body, FIG.
A conductive member that covers the sensor surface (detection surface) of the magnetic toner sensor 3 as shown in FIG. 2A and retracts from the sensor surface when the toner cartridge 1 is mounted as shown in FIG. 10 is provided in the apparatus main body. As a method of moving the conductive member 10, for example,
By providing a projection having a shape shown by a broken line on the bottom surface of the toner cartridge 1 and providing a spring or the like (not shown) for movably supporting the conductive member 10 in a direction indicated by an arrow in the figure, the toner cartridge When the toner cartridge 1 is not mounted, the conductive member 10 is supported at a position covering the sensor surface by a spring or the like. When the toner cartridge 1 is mounted, the conductive member 10 is pushed by the above-described projection in the direction of the arrow in FIG. Configuration. Also,
In the present embodiment, at least a portion of the toner stirring member 2 facing the sensor surface of the magnetic toner sensor 3 is formed of a non-conductive member 9 larger than the area of the sensor surface of the magnetic toner sensor 3 (note that the toner stirring member is not limited). 2 may be formed entirely of a non-conductive member). Also, the magnetic toner sensor 3
Is performed when the toner in the toner cartridge 1 is being stirred by the toner stirring member 2.

In the configuration of this embodiment, the detection output of the magnetic toner sensor 3 indicates that the conductive member 10 covers the sensor surface of the magnetic toner sensor 3 when the toner cartridge 1 shown in FIG. Therefore, a state as shown in FIG. 4 is obtained. When the toner cartridge 1 having toner in the toner storage section 1A is mounted as shown in FIG. 2B, the conductive member 10 is retracted from the sensor surface, and the state inside the toner cartridge 1 is detected. However, the stirring operation of the toner stirring member 2 causes the non-conductive member 9 at the tip of the toner stirring member 2 to periodically rotate around the sensor surface. Therefore, the detection output of the magnetic toner sensor 3 is as shown in FIG. When the toner is consumed and the toner in the toner cartridge 1 runs out, nothing is detected, and the detection output of the magnetic toner sensor 3 is in a state as shown in FIG. According to the state of the detection output of the magnetic toner sensor 3, both the presence or absence of the toner and the presence or absence of the toner cartridge 1 can be independently detected.

(Embodiment 2) FIG. 3 is an explanatory view of a main part of an image forming apparatus according to a second embodiment of the present invention. In the image forming apparatus of this embodiment, in addition to the configuration of FIG. 1, at least a portion of the toner agitating member 2 facing the sensor surface of the magnetic toner sensor 3 is made of a conductive material larger than the area of the sensor surface of the magnetic toner sensor 3. The toner agitating member 2 may be formed of a conductive member. The detection by the magnetic toner sensor 3 is performed when the toner in the toner cartridge 1 is stirred by the toner stirring member 2.

In the configuration of the present embodiment, the detection output of the magnetic toner sensor 3 is not detected when the toner cartridge 1 is not present, so that a state as shown in FIG. 6 is obtained. When the toner cartridge 1 containing toner is mounted in the toner storage section 1A, the internal state of the toner cartridge 1 is detected. However, the stirring operation of the toner stirring member 2 causes the toner stirring member 2 The conductive member 11 at the tip will rotate periodically,
When the toner cartridge 1 is sufficiently filled with toner, the detection output of the magnetic toner sensor 3 is in the state shown in FIG. 4, but when the toner is consumed and the toner in the toner cartridge 1 decreases, FIG. It changes to a state like. When the toner in the toner cartridge 1 runs out, only the portion where the conductive member 11 of the toner stirring member 2 periodically rotates on the sensor surface of the magnetic toner sensor 3 is detected by the stirring operation of the toner stirring member 2. That is, the detection output of the magnetic toner sensor 3 is in a state as shown in FIG. From the above detection output state, it is possible to independently detect both the presence or absence of the toner and the presence or absence of the toner cartridge 1.

In the first and second embodiments, the detection output of the magnetic toner sensor 3 may be configured such that the logics of "H" and "L" are reversed. Further, the developing device is a toner cartridge 1 in which the toner storage section 1A and the developing section 1B are integrated.
However, the same effect can be obtained even when only the toner storage section 1A is detached as a toner cartridge. Furthermore, although the description has been given of the case where the developing device is an independent toner cartridge 1, as a cartridge (image forming cartridge) including the photoconductor 5 and the cleaning device 7 in the toner cartridge, the image forming cartridge is detached from the apparatus main body. The same effect can be obtained as a configuration.

[0018]

As described above, in the image forming apparatus according to the first aspect, the magnetic toner sensor for detecting the presence or absence of toner in the toner cartridge, and the magnetic toner sensor when the toner cartridge is not mounted. A conductive member that covers the sensor surface and is evacuated from the sensor surface when it is mounted; and a toner stirring member in the toner cartridge that faces the sensor surface of the magnetic toner sensor. The toner stirring member faces at least the sensor surface. By using a non-conductive member for the unit, two types of detection, that is, the presence or absence of a toner and the presence or absence of a toner cartridge, can be performed in one.
Since the detection can be performed using the two magnetic toner sensors, the cost of the image forming apparatus can be reduced.

In the image forming apparatus according to the second aspect,
A magnetic toner sensor for detecting the presence or absence of toner in the toner cartridge, and a toner stirring member in the toner cartridge facing the sensor surface of the magnetic toner sensor,
2. A magnetic toner sensor according to claim 1, wherein at least a portion of the toner agitating member facing the sensor surface is formed of a conductive member, so that two types of detection, that is, presence / absence of toner and presence / absence of a toner cartridge, are performed with less configuration than that of the first embodiment. , The cost of the image forming apparatus can be further reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of an electrophotographic image forming apparatus according to the present invention.

FIG. 2 is an explanatory diagram of a main part configuration of the image forming apparatus according to an embodiment of the present invention, in which (A) is a diagram illustrating a state in which a toner cartridge is removed and a sensor surface is covered with a conductive member;
FIG. 3B is a diagram illustrating a state where the toner cartridge is mounted and the conductive member is retracted from the sensor surface.

FIG. 3 is an explanatory diagram of a main configuration of an image forming apparatus according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating an example of a detection output waveform of a magnetic toner sensor in the image forming apparatus of the present invention.

FIG. 5 is a diagram illustrating another example of a detection output waveform of a magnetic toner sensor in the image forming apparatus of the present invention.

FIG. 6 is a diagram illustrating still another example of the detection output waveform of the magnetic toner sensor in the image forming apparatus of the present invention.

FIG. 7 is a diagram showing still another example of the detection output waveform of the magnetic toner sensor in the image forming apparatus of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Toner cartridge (developing device) 1A Toner storage unit 1B Developing unit 2 Toner stirring member 3 Magnetic toner sensor 4 Developing roller 5 Photoconductor (electrostatic latent image holding member) 6 Transfer roller 7 Cleaning device 8 Charging device 9 Toner stirring member Non-conductive member constituting 10 Conductive member 11 Conductive member constituting toner stirring member

Claims (2)

[Claims] An electrostatic latent image formed on an electrostatic latent image holding member is developed into a visible image by developing with a magnetic toner supplied from a toner cartridge, and then the toner image is transferred to a transfer material. In an electrophotographic image forming apparatus for forming an image, a magnetic toner sensor for detecting the presence or absence of toner in the toner cartridge and a sensor surface of the magnetic toner sensor when the toner cartridge is not mounted are mounted and mounted. A conductive member that retreats from the sensor surface when the sensor is on, and a toner stirring member in the toner cartridge that faces the sensor surface of the magnetic toner sensor, and at least a portion of the toner stirring member that faces the sensor surface is non-contact. It is composed of a conductive member, and the presence or absence of the toner and the presence or absence of the toner cartridge are determined by the state of the detection output of the magnetic toner sensor. An image forming apparatus for detecting. 2. An electrostatic latent image formed on an electrostatic latent image holding member is developed into a visible image by developing with a magnetic toner supplied from a toner cartridge, and then the toner image is transferred to a transfer material. An electrophotographic image forming apparatus for forming an image, comprising: a magnetic toner sensor for detecting presence or absence of toner in the toner cartridge; and a toner stirring member in the toner cartridge facing a sensor surface of the magnetic toner sensor. Image forming wherein at least a portion of the toner agitating member facing the sensor surface is formed of a conductive member, and presence / absence of toner and presence / absence of a toner cartridge are detected based on a detection output state of the magnetic toner sensor. apparatus.