JPH01316765A - Developing device for image forming device - Google Patents

Abstract

PURPOSE:To detect the accurate rest of a developer by arranging a light- transmissive transparent member where an agitating and conveying means for a developer container is brought into slide contact. CONSTITUTION:Rest inspection windows 71 and 72 which consists of transparent members are embedded in the flank and bottom surface of a toner container 3a at an equal distance from the center of rotation of an agitation rod 3e. Then when the agitation rod 3e rotates in the toner container 3c, an agitation sheet member 3f is rubbed against the surfaces of the rest inspection windows 71 and 71 at each time to sweep toner. When toner (t) in the toner container 3c is sent into a developing device 3b through a communication hole 3d by the rotation of the agitation rod 3e and consumed during the formation of an image, the amount of the toner (t) in the toner container 3c decreases gradually, but when light emitted by a light emission part 74 reaches a light reception part 73 through the rest inspection windows 71 and 72, the light reception part 73 is irradiated with the light and generates a voltage. Consequently, the rest of the toner (t) in the toner container 3c is accurately known.

Description

[Detailed Description of the Invention] (Industrial Application Field) What is the present invention? The 11-child photocopying device and the electrostatic recording bag relate to a developing device of an image forming device such as a laser beam printer.

(Prior Art) In an image forming apparatus, an image carrier such as an electrophotographic photoreceptor or an electrostatic recording dielectric undergoes a series of processes such as charging, development, and cleaning on its surface while rotating.

However, in order to detect the remaining amount of developer in the developing device, the number of rotations of the image carrier is calculated to determine the amount of developer used per one rotation of the image carrier, and the accumulated amount of the image carrier is calculated. This was done by determining the number of revolutions.

(Problem to be Solved by the Invention) However, the image carrier rotates not only when printing is performed using developer, but also when the user turns it by hand. The amount of developer used per rotation is not constant, and therefore, the detection of the remaining amount of developer lacks accuracy and reliability.

The present invention has been made in view of the above problems, and an object thereof is to provide a developing device for an image forming apparatus that can accurately detect the remaining amount of developer.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a developing device of an image forming apparatus that includes a developer stirring/transporting means in a developer container. The present invention is characterized in that a light-transmitting transparent member is disposed at a portion in sliding contact with the conveyance means.

(Function) Since the remaining amount of developer can be directly detected by the sensor by detecting the light transmitted through the transparent member, the remaining amount of developer can be accurately detected. As for the detection method.

A light transmission method, a light reflection method, etc. can be adopted.

(Example) Embodiments of the present invention will be described below based on the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a process cartridge equipped with a developing device according to the present invention, and FIG. 2 is a partial perspective view of the same process cartridge.

The process cartridge 100 is configured to be detachably attached to the main body of an image forming apparatus (not shown), and a photosensitive drum l as an image carrier is rotatably disposed inside the housing 10 of the process cartridge 100 on the right side in the figure. When the process cartridge 100 is removed from the main body of the image forming apparatus, the photosensitive tram l is covered by the protective cover (drum cover) 5 in the closed state shown by the solid line in the figure, and is protected from damage. Deterioration caused by external light is prevented.

Note that when the process cartridge 100 is loaded into the main body of the image forming apparatus, the protective cover 5 is opened as shown by the chain line in FIG. 1 by a mechanism not shown, and a part of the photosensitive drum l is It is exposed to the outside through the opening 11. and,
This photosensitive drum l.

In FIG. 1 of the housing IO, an optical image exposure light (
The optical image exposure process section 19 receives irradiation with light (such as slit exposure light, laser beam scanning exposure light, etc.) for the original image. In FIG. 1, numeral 8 is a transfer charger provided on the mounting main body side.

Further, within the housing 10 is a charging device 2. A cleaning noodle ff14 and a developing device W13 are provided, but the charging device 2
The cleaning device 4 has a substantially horizontal optical image exposure optical path 1 extending from the exposure window 6 to the optical image exposure process section 19 of the photosensitive drum l.
7, and the developing device ff13 is located above the same light image exposure optical path 1.
It is placed below 7.

The charging device 2 includes a contact charging roller (or frictional charging roller) 2A that rotates in sliding contact with the photosensitive tram l, and the contact charging roller 2A is connected to a cleaning device i14.
It is housed in the recess 20 of. Also, a charger! ! 12 may be a corona charger.

Also, the cleaning equipment mentioned above! ! 4 includes a cleaning blade C4a made of rubber or the like, and the cleaning blade 4a is in contact with the upper surface of the photosensitive drum l on the upstream side in the rotational direction of the photosensitive drum l than the contact charging roller 2A. .

Further, the developing device t3 has a developing device 3b that accommodates the developing roller 3a, and a toner container 3c that is provided in series on the left side of the developing device 3b, and the developing device 3b and the toner container 3c are provided on a partition wall between them. They are communicated via a communication hole 3d.

The toner t in the toner container 3b is agitated by the 152 stirring rod 3e being driven to rotate at a predetermined speed, and a portion of the toner t is connected to the communication hole by the stirring sheet member 3f attached to the tip side of the stirring rod 3e. The toner is intermittently fed from 3d into the developing device 3b every rotation of the stirring rod 3e to be replenished.

Note that the upper part of the toner container 3c is closed with a lid member 3g. Also, a developing roller 3a.

A required voltage (charging voltage, developing bias) is applied to the charging roller 2A.

Then,! i! The optical drum 1 is uniformly charged positively or negatively by the charging roller 2A, and a latent image is formed by receiving light for exposing the optical image in the optical image exposure process section 19, and the latent image is formed into a toner image by the developing roller 3a. It is developed as Then, the toner image is sequentially transferred to the surface of the copying material P fed from a paper feeding mechanism (not shown) between the photosensitive drum 1 and the transfer charger 8 in the image transfer process section. The copying material P that has undergone image transfer and has been separated from the photosensitive drum l surface is transferred to a fixing device! ! (not shown), undergoes image fixation, and is discharged outside the machine as a copy. On the other hand, the surface of the photosensitive drum 1 after the image transfer is wiped off by the cleaning blade 4a of the cleaning device 4 to remove residual toner after transfer and other deposits to make the surface clean, and the surface is repeatedly used for image formation.

By the way, residual inspection windows 71 and 72 made of transparent members are fitted into the side and bottom surfaces of the toner container 3C, respectively, and these residual inspection windows 71 and 72 are equidistant from the center of rotation (stirring center) of the stirring rod 3e. It is placed in the position of

Further, on the side of the developing device 3 outside the process cartridge 100, an L-shaped sensor stand 70 is installed along with the residual inspection window 71,
72 from the outside, and a light emitting section 74 and a light receiving section 73 are arranged on the sensor stand 70 so as to cover the remaining inspection windows 71 and 7.
They are arranged facing each other so as to sandwich the two. In addition, the light emitting part 7
4 is composed of a lamp, a light emitting diode, etc., and the light receiving section 73 is composed of an element such as a photoelectric cell that converts light into electric current.

Then, when the stirring rod 3e rotates within the toner container 3c,
Each time, the stirring sheet member 3f rubs the surface of the residual inspection window 71, 72 to wipe and remove the toner t.

When one image is formed, when the toner t in the toner container 3c is sent into the developing device 3b through the communication hole 3d and consumed by the rotation of the stirring rod 3e, the amount (remaining amount) of the toner t in the toner container 3C increases. When the light emitted from the first light emitting section 74 gradually decreases or reaches the light receiving section 73 through the remaining inspection windows 71 and 72, the light receiving section 73 receives the irradiation of this light and generates a voltage. By detecting this voltage level, the remaining amount of toner t in the toner container 3c can be known. In this embodiment, since the residual inspection windows 71 and 72 are arranged at positions equidistant from the stirring center as described above, these residual inspection windows 71 and 72 are rubbed with equal pressure by the stirring sheet member 3f. The toner t is then wiped off from the surface.

As described above, in this embodiment, since the actual amount of toner is directly detected by the sensor (the light emitting section 74 and the light receiving section 73), accurate and stable remaining amount detection is always performed. Furthermore, since the sensor composed of one light emitting section 74 and one light receiving section 73 is small, it is easy to install and can detect the remaining amount of toner at a very low cost.

In the above embodiment, the residual inspection windows 71 and 72 made of a transparent material are partially provided in the toner container 3c, but the entire toner container 3c may be made of a transparent material.

Next, modified embodiments of the present invention are shown in FIGS. 3 to 6, respectively. In these figures, the same elements as shown in FIGS. 1 and 2 are given the same reference numerals. .

In the embodiment shown in FIG. 3, the sensor stand 80 is formed into a U-shape, and the position of the residual inspection window 71 is moved close to the developing device 3b, so that the toner t sent by the stirring bar 3e can be transferred to the developing device 3b.
The amount of toner immediately before it enters the toner t can be detected based on the state of adhesion of the toner t to the residual inspection window 71.

Further, in the embodiment shown in FIG. 4, the sensor stand 80 is formed into a U-shape as in the above embodiment, but the residual inspection windows 71 and 72 are located far away from the developing unit 3b. ,
Further, they are arranged above and below the toner container 3C. With this configuration, the toner empty state can be detected before the toner t is completely exhausted in the toner container 3c, so this embodiment is particularly suitable for an image forming apparatus with a fast development speed.

Furthermore, in the embodiments shown in FIGS. 5 and 6, the sensor itself is the same as that of the first embodiment, but the detection method is changed from a light transmission method to a light reflection method. In each embodiment, by configuring the residual inspection window 83 with a white plate, the light emitted from the first light emitting section 74 is reflected by the residual inspection window 83 and reaches the light receiving section 73, thereby determining the remaining amount of toner. Detected.

If the above-mentioned light reflection method is used as a detection method, the sensor stands 82, 84 themselves can be downsized, and the space for installing them can be reduced.

Further, if the toner container 3c itself is made white, only one residual inspection window is required.

5 shows an example in which the sensor stand 82 is installed below the developing device 3b, and FIG. 6 shows an example in which the sensor stand 84 is installed below the toner container 3b.
An example of installation below c is shown.

(Effects of the Invention) As is clear from the above description, according to the present invention, in the developing device of an image forming apparatus, which includes a developer stirring/transporting means in a developer container, the stirring/transporting means of the developer container is provided. Because a light-transmitting transparent member is placed in the area where the
By detecting the light that passes through the transparent member, it is possible to directly and accurately detect the remaining amount of developer.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a process cartridge equipped with a developing device according to the present invention, FIG. 2 is a partial perspective view of the same process cartridge, and FIGS. 3 to 6 are views of process cartridges showing modified embodiments of the present invention. FIG. 3...Developing device, 3C...Toner container (developer container), 3d-...Communication hole (developer opening), 3e...Stirring bar (stirring/conveying means), 71, 72.83 ...Remaining inspection window (transparent member).

Claims (2)

[Claims] (1) In a developing device of an image forming apparatus including a developer stirring/transporting means in a developer container, a light-transmissive transparent member is disposed at a portion of the developer container in which the stirring/transporting means slides. A developing device for an image forming apparatus, characterized in that: (2) The image according to claim 1, wherein the transparent member is provided on the lower surface of the developer container in the direction of gravity, and the developer opening is arranged on the downstream side of the transparent member in the direction of rotation of the stirring/conveying means. Developing device of forming device.