JPH0695501A - Electrophotographic image forming device - Google Patents

Abstract

PURPOSE:To provide an electrophotographic image forming device in which a drum cartridge and developer cartridges are removable and the replacement time of a photoreceptor drum can surely be controlled. CONSTITUTION:In an electrophotographic image forming device, wherein both a drum cartridge 10 provided with a photoreceptor drum 1 and developer cartrigde 20 enclosing a developer 6 can be independently installed and removed, the drum cartridge 10 is provided with recessed portions 11-i (i=1 to (n)) by the same number as that (n) of developer cartridges 20 used within the longevity of the photoreceptor drum 1, and the developer cartridges 20-k provided by the number (m) are each provided with a projecting portion 21-k which is fitted into only the specific one 11-k((k) is a specific value from 1 to (n)) of the recessed portions 11-i when the cartridges are normally installed, and the projecting portions 21-i differ in the projecting position and are provided with a replacement time reporting means 200 so provided as to be easily removable from each developer cartridge 20-i.

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, and more particularly to an electrophotographic image forming apparatus in which a drum cartridge and a developer cartridge are attached and detached.

[0002]

2. Description of the Related Art FIG. 5 is a conceptual diagram of the configuration of an electrophotographic image forming apparatus. As shown in the figure, a photosensitive drum 1 whose surface is coated with a photoelectric layer made of a photoconductive material is shown in FIG. By being driven to rotate around, the surface of the photosensitive drum 1 is charged to one polarity by the charger 2, and the surface of the photosensitive drum 1 is electrostatically charged by the light beam scanned from the irradiation device 3 based on predetermined image data. Form a latent image. After that, the developing position D
The developer 6 in the developing device 30 is supplied to the photosensitive drum 1 by the mag roller 4 to develop the electrostatic latent image into a toner image,
At the transfer position P, this toner image is transferred onto the printing paper 7.

As the developer 6, for example, a two-component type developer in which a carrier made of a magnetic material, a toner containing a synthetic resin and carbon are mixed is mainly used, and the stirring paddle 5 is used.
Only the toner of the developer which has been stirred and charged by the above is attached to the surface of the photosensitive drum 1 and consumed. The toner concentration in the developer 6 is detected by a toner concentration sensor 8 arranged in the developing device 30 to maintain a predetermined image quality.

By the way, in many electrophotographic image forming apparatuses, the consumption of toner and the deterioration of the photoelectric layer of the photosensitive drum 1 progress with the operation, so that the photosensitive drum 1 and the developer 6 are used.
The developing device 30 accommodating the cartridge is mounted in a single cartridge, and the cartridge is replaced with a new cartridge at an appropriate time.

However, since the toner consumption speed is higher than the service life of the photoconductor drum, it is necessary to replace the photoconductor drum that can withstand sufficient use by replacing the developer, and vice versa. The developer that can be used to replace the deteriorated photosensitive drum must also be replaced. In many cases, the used cartridge is discarded as it is without being reused, which causes a running cost and is inconvenient from the viewpoint of resource saving.

Therefore, in recent years, an electrophotographic image forming apparatus has been provided which is divided into a drum cartridge equipped with a photosensitive drum and a developer cartridge containing a developer, which can be attached and detached independently of each other. There is.

[0007]

In the electrophotographic image forming apparatus in which the drum cartridge provided with the photosensitive drum and the developer cartridge containing the developer are exchanged independently of each other, the developer cartridge As in the conventional case, the replacement time is grasped based on the output from the means for directly detecting the toner density in the developer such as the toner density sensor, while the drum cartridge replacement time is counted, for example, the number of printed sheets. It is indirectly known based on the value in the counter.

However, since the count value in the counter can be reset relatively easily, if the counter is reset by mistake, the replacement time of the drum cartridge may be missed, and the photosensitive drum may deteriorate. This causes inconvenience such as deterioration of image quality.

The present invention has been proposed in view of the above conventional circumstances, and an object of the present invention is to provide an electrophotographic image forming apparatus capable of reliably managing the replacement time of the photosensitive drum. To do.

[0010]

In order to achieve the above object, the present invention employs the following means. That is, as shown in FIGS. 1 and 2, the electrophotography capable of independently attaching and detaching the drum cartridge 10 including the photosensitive drum 1 and the developer cartridge 20 containing the developer 6 is independently performed. Type image forming apparatus, the photosensitive drum 1
The number of the recesses 11-i (i = 1 to n) equal to the number n of the developer cartridges 20 used within the life of the drum cartridge 10 are provided, and the recesses 11-i are identified in the normal mounting state. No. 1 of the concave portion 11-k (K is a specific value among 1 to n) is provided with the convex portion 21-k in each of the developer cartridges 20-k of the above-mentioned number n. 21-i has a different projecting position, and each developer cartridge 20
The replacement timing informing means 100 is provided so as to be easily detached from -i.

Further, the judging means 110 for judging whether or not the developer cartridge 20-i is in a normal mounting state.
Is preferably added to the replacement time notification means 100. The Specifically, for example the determination unit 110, with mounting the DC power source E _i of n groups corresponding to the respective recesses 11-i to the drum cartridge 10, the terminal to be connected to one pole of the DC power source E _i 12- i and the terminal 13-i grounded to the fuselage are provided on the inner wall of the recess 11-i, while the projection 21-i is fitted in the recess 11-i.
-a loop line 2 connected to i and opened when the developer cartridge 20-i is detached from the electrophotographic image forming apparatus
2-i may be provided and the mounting detection signal S _i corresponding to the potential of the terminal 12-i may be output.

[0012]

According to the above construction, as shown in FIGS. 1 and 2, for example, when one developer cartridge 20-1 is properly mounted, the projecting portion 21 protruding from the developer cartridge 20 is provided. Is a specific concave portion 11 out of n concave portions 11 provided in the drum cartridge 10 in the same number as the number of times of replacement.
Insert into -1.

After that, when the toner concentration of the developer cartridge 20-1 decreases, the developer cartridge 20-1
When -1 is separated from the drum cartridge 10, the convex portion 21-1 is separated from the developer cartridge 20 while being fitted in the concave portion 11-1.

Instead, another developer cartridge 20 is used.
When the -2 is attached to the device, the convex portion 21 is the same as above.
-2 corresponds to another recess 11-2 of the drum cartridge 10
Fit in.

After the replacement of the n-group developer cartridges 20 in this manner, the projections 21 detached from the developer cartridge 20 are all fitted into the n recesses 11. Subsequent replacement of the developer cartridge 20 with respect to the drum cartridge 10 is physically impossible, which prompts replacement of the drum cartridge 10.

Further, the judging means 110 for judging whether the developer cartridge 20 is in the normal mounting state is composed of the ground side terminal 13-i of the concave portion 11-i to the convex portion 21-i.
Through the developer cartridge 20-i through the concave portion 1 again.
A loop line 22-i returning to the terminal 12-i of 1-i is formed, and when the convex portion 21-i is normally attached to the concave portion 11-i, the loop line 22-i is closed and is normally attached. If not, the loop line 22-i is opened, and the mounting detection signal S _i is output when the potential of the terminal 12-i fluctuates. For example, as shown in FIG. 2 (c), the convex portion 21 is detached. The electrophotographic image forming apparatus is prevented from operating when the developer cartridge 20 is mounted.

[0017]

EXAMPLE An example according to the present invention will be described in detail below. 1 is a configuration diagram of an embodiment according to the present invention, FIG. 2 is a configuration diagram of a main part thereof, FIG. 3 is a flow chart of replacement work of this embodiment, and FIG. It is a figure.

First, in this embodiment, it is defined that the two developer cartridges 20 are used within the life of the photosensitive drum 1. 1 and 2, the photosensitive drum 1
Two recessed portions 11 (11-1, 11-2) are provided side by side in the lateral direction at the lower rear end portion of the drum cartridge 10 in which the developer 6 is accommodated, and two developer cartridges 20 containing the developer 6 are provided.
-1, 20-2 at the lower front end of each recess 11 (11-
1, 21-2), the convex portion 21 (21-1, 21-
2) is provided so as to constitute the replacement time notification means 100.

The convex portion 21 has an umbrella-like tip, while the concave portion 11 has a wide interior and a narrow inlet, and is made of a flexible material. As a result, the convex portion 21 is strong and the concave portion 1 is strong.
If you try to install it by pushing it into
The inlet is pushed by the umbrella-shaped tip portion of the convex portion 21 and spreads, and when the tip portion fits inside the concave portion 11, the inlet becomes the original size due to its elastic restoring force and the two are separated. Is prevented.

The convex portion 21 (21-1, 21-2) is fitted only in the concave portion 11 of a specific one of the plurality when the developer cartridge 20 is normally mounted, and the convex portion 21 It can be easily detached from the developer cartridge 20-1 by folding the base end portion thereof.

Further, the drum cartridge 10 includes
Two DC power sources E ₁ corresponding to the recesses 11-1 and 11-2,
E ₂ and terminals 12-1 connected to the DC power supplies E ₁ and E ₂ ,
12-2 and terminals 13-1 and 13-2 grounded to the machine body are provided. On the other hand, each developer cartridge 20-1, 20
-2, the convex portions 21-1 and 21-2 are respectively formed into concave portions 11-1 and 1-2.
The terminal 12-1 and the terminal 13-1, which are fitted in 1-2,
Alternatively, the loop wire 2 connecting the terminal 12-2 and the terminal 13-2
By providing 2-1 and 22-2, the judging means 110 is added to the replacement timing notifying means 100.

The determination means 110, as will be described later,
Mounting detection signals S ₁ and S corresponding to the recesses 11-1 and 11-2, respectively.
₂ is output to an electrophotographic image forming apparatus (not shown), and the operation of the apparatus becomes possible when at least one of the mounting detection signals S ₁ and S ₂ becomes the potential “0”. I am trying.

In the procedure for mounting the drum cartridge 10 and the developer cartridges 20-1 and 20-2 in the electrophotographic image forming apparatus, the drum cartridge 10 and the first developer cartridge 20-1 are not shown. It is attached to the electrophotographic image forming apparatus (FIG. 3F1). At this time,
As shown in (a), the terminal 12-1 of the recess 21-1 is connected to the terminal 13-1 through the loop wire 22-1 and is grounded to the airframe. As a result, the mounting detection signal S ₁ output toward the electrophotographic image forming apparatus (not shown) connected in parallel with the terminal 12-1 is the potential "0" as shown in FIG. 4 (a). As a result, the fact that the developer cartridge 20-1 has been normally attached is notified and the operation of the apparatus is guaranteed.

While the electrophotographic image forming apparatus is in operation, the toner density of the developer 6 is always detected by a predetermined means such as a toner density sensor (F2No → F2 in FIG. 3), and then the toner density shortage is detected. Then, the first developer cartridge 20-1 is detached from the electrophotographic image forming apparatus in order to replace the developer 6 (F2 Yes → F in FIG. 3).
3). Since the convex portion 21-1 is fitted in the concave portion 11-1 and the base end portion thereof has a small diameter, it is ruptured at the base end portion upon detachment as shown in FIG. 2 (b). . Therefore, the loop line 22
It is cut in the middle of -1, and the terminal 12-1 and the terminal 13-1 are insulated. As a result, as the potential of the terminal 12-1 rises, the mounting detection signal S ₁ becomes the potential "1", and the two mounting detection signals S ₁ and S ₂ both become the potential "1". The image forming apparatus cannot be operated.

Next, the second developer cartridge 20-2
Mounted on the drum cartridge 10 (FIG. 3F4),
The terminal 12-2 of the recess 11-2 is connected to the terminal 13-2 through the loop wire 22-2, and as shown in FIG.
The mounting detection signal S ₂ output from 1-2 has a potential of "0" to inform that the developer cartridge 20-2 is mounted normally.

In the same manner, the toner density is constantly checked (F5 No → F5 in FIG. 3), and in response to the shortage of the toner density thereafter, the second developer cartridge 20-2 is replaced for replacing the developer 6. It is detached from the drum cartridge 10 (FIG. 3, F5 Yes → F6). Also at this time, the convex portion 21-2
Is broken at the base end and the loop wire 12-2 is cut midway, so the potential of the terminal 12-2 rises and the two mounting detection signals S ₁ and S ₁ Both ₂ are at the potential "1" and the equipment cannot be operated.

In this state, the drum cartridge 1
From the place where the separated convex portions 21-1 and 21-2 are fitted in the two concave portions 11-1 and 11-2 of 0, the terminal 1
It becomes impossible to connect 2-1 and terminal 13-1, or terminal 12-2 and terminal 13-2. Therefore, in this drum cartridge 10, since it is impossible to set the potential of at least _{one of} the mounting detection signals S ₁ and S ₂ to “0”, a new drum cartridge is replaced (FIG. 3).
F7 → F1).

As described above, in this embodiment, the replacement timing of the second developer cartridge 20-2 and the replacement of the drum cartridge 10 among the developer cartridges 20 of which the toner density is directly detected to notify the replacement. Since the timings can be matched, it is possible to operate the electrophotographic image forming apparatus with stable image quality without delaying the replacement time of the drum cartridge 10.

Further, as shown in FIG. 2 (c), for example, a developer cartridge in which the convex portion 21 is accidentally detached before being mounted on the electrophotographic image forming apparatus or a used developer cartridge is Can be physically installed, but recess 1
Since the terminal 12 and the terminal 13 provided in No. 1 are not connected, the mounting detection signals S ₁ and S ₂ both remain at the potential “1”, and the electrophotographic image forming apparatus does not operate. Therefore, by providing the determination means 110, it is possible to prevent the operation in an abnormal mounting state, and it is possible to eliminate the difference in the replacement timing of the drum cartridge 10 caused by this.

The present invention is not limited to the above embodiment, the number of times of replacement can be set arbitrarily, and the shape of the concave and convex portions, the determining means, etc. can be changed appropriately according to the usage. Of course.

[0031]

As described above, according to the present invention, the electrophotographic image forming apparatus is configured such that the drum cartridge provided with the photosensitive drum and the developer cartridge containing the developer are independently attached and detached. In the above, since it is possible to manage the replacement time of the drum cartridge, which was difficult to properly manage, on the basis of the replacement time of the developer cartridge, the replacement time of the drum cartridge is not missed and stable. Images can now be formed with high image quality.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment according to the present invention.

FIG. 2 is a configuration diagram of main parts of an embodiment according to the present invention.

FIG. 3 is a work flow diagram of an embodiment according to the present invention.

FIG. 4 is a timing chart of the output of the judging means of the embodiment according to the present invention.

FIG. 5 is a conceptual diagram of an electrophotographic image forming apparatus.

[Explanation of symbols]

1 Photoreceptor Drum 6 Developer 10 Drum Cartridge 11-i Recessed 12-i Terminal 13-i Terminal 20 Developer Cartridge 21-i Convex 22-i Loop Line 100 Replacement Timing Indication Means 110 Judgment Means E _i DC Power Supply S _i Mounting detection signal n (Number of developer cartridges)

Claims (3)

[Claims] 1. An electronic device capable of independently attaching and detaching a drum cartridge (10) equipped with a photosensitive drum (1) and a developer cartridge (20) containing a developer (6). In a photographic image forming apparatus, the same number of recesses (11-i: i = 1 to n) as the number (n) of developer cartridges (20) used within the service life of the photoconductor drum (1) are set in the drum cartridge. A convex portion provided on (10) and fitted only in a specific one concave portion (11-k: K is a specific value of 1 to n) of the concave portions (11-i) in a normally mounted state. (21-k) to each developer cartridge (2
0-k), the convex portions (21-i) have different projecting positions between the developer cartridges (20-k), and the developer cartridges (2
An electrophotographic image forming apparatus characterized by comprising a replacement timing notifying means (100) which is provided so as to be easily separated from 0-i). 2. The replacement timing informing means (100) according to claim 1, further comprising a determining means (110) for determining whether or not the developer cartridge (20-i) is in a normally mounted state. Electrophotographic image forming apparatus. 3. The determination means (110) comprises a n-group DC power supply (E _i ) corresponding to each of the recesses (11-i) mounted on a drum cartridge (10), and the DC power supply.
(E _i ) The terminal (12-i) connected to one pole and the terminal (13-i) grounded to the fuselage are provided on the inner wall of the recess (11-i), while the projection (21-i) is provided. With the terminal (12-i) fitted in the recess (11-i),
i) and the terminal (13-i) are connected, and a loop line (22-i) which is opened when the developer cartridge (20-i) is detached from the electrophotographic image forming apparatus is provided, The electrophotographic image forming apparatus according to claim 2, wherein a mounting detection signal (S _i ) corresponding to the potential of the terminal (12-i) is output.