JPH0429162A - Image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to image forming apparatuses employing electrophotography, such as copying machines, laser beam printers, facsimile machines, and the like.

(Prior Art) In an image forming apparatus such as a laser beam printer, image forming devices such as an image bearing member and a developing device are integrally assembled in a cartridge container, and these are removably attached to the apparatus body as a process cartridge. There are many types that can be installed.

This process cartridge is designed to facilitate maintenance by replacing the entire process cartridge when the image bearing member reaches the end of its life or the developer (toner) in the developing device is used up. Also,
By filling the developing device with toner of different colors and replacing the process cartridge, it is also possible to form multicolor images.

An example of such a process cartridge will be described with reference to FIG. 11. The process cartridge 100 has a photosensitive tram 101 as an image carrier, a developing device, etc. in a cartridge container 100a, and can be freely attached and detached to a predetermined position in the apparatus main body 200. It is arranged.

When this process cartridge 100 is installed in the apparatus main body 200, the tram gear 101a provided at the right end of the photosensitive drum 101 and the drive gear 20 on the apparatus main body 200 side are connected to each other.
1 and 2 engage with each other, and the photosensitive tram 101 becomes rotatable by a drive source (not shown) via a drive gear 201 on the apparatus main body 200 side.

Further, the transmission gear 101b provided at the left end of the photosensitive drum 100 meshes with the transfer gear 202a of the transfer roller 202 on the apparatus main body 200 side, and the rotational force of the photosensitive drum 101 is also transmitted to the transfer roller 202.

Further, when the process cartridge 100 is installed in the apparatus main body 200, the plate spring 203 on the apparatus main body 200 side is pressed and expanded, the switch 204 is turned on, and the process cartridge 100 is installed in the apparatus main body 200. It is displayed on the panel etc.

(Invention or problem to be solved) However, the above process cartridge 100
In the image forming apparatus equipped with this, the plate spring 203 is used except for the driving force transmission system, such as meshing the drive gear 201 on the apparatus main body 200 side with the tram gear 101a, or meshing the transmission gear 101b with the transfer gear 202a. switch 20
4, only the determination of whether or not the process cartridge 100 is attached or detached has been made.

Therefore, whether there is any problem with the specifications of the process cartridge 100 with the same performance and the same print density, or whether the process cartridge 100 with different specifications regarding print density and which also requires adjustment of the equipment on the apparatus main body 200 is suitable for such an image forming apparatus. There were some inconveniences such as not being able to meet the specifications.

The present invention was made in view of the above problems, and an object of the present invention is to automatically form appropriate images with different print densities by installing and removing process cartridges with different specifications regarding print density. to provide possible imaging.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides an image forming apparatus in which a process cartridge having at least an image bearing member and a developing means or a process cartridge or a process cartridge having a developing means in addition to an image bearing member is removably disposed in an apparatus main body. A detection means that detects when a process cartridge with different specifications is installed in the apparatus main body, and a detection means that detects the rotation speed of the polygon mirror on the apparatus main body side, the frequency of the image clock of the laser device, and the laser beam based on the signal from the detection means. The present invention is characterized by the provision of a control means for automatically switching the size and process conditions in accordance with the specifications regarding print density on the process cartridge side.

(Function) When installing process cartridges with various specifications regarding printing density into the apparatus main body to form images with different printing densities, the rotation speed of the polygon mirror on the apparatus main body side, the frequency of the image clock of the laser device, the laser Is it necessary to change process conditions such as beam size and fusing temperature?

Therefore, the type of process cartridge related to printing density is detected by the detection means, and based on the detection signal, the conditions on the main body side of the apparatus, such as the rotation speed of the polybon mirror, can be automatically switched by the control means.

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

First, a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

First, as shown in FIG. 1, l! Explain the main points.

In the figure, lO is a photosensitive drum which is an image bearing member, and around the photosensitive drum 10, image forming means such as a primary charger 11, a developing device 12, a cleaning device 13, and a transfer means such as a transfer roller 14 are arranged. . A paper feed cassette 15, a paper feed roller 16, and a registration roller 17 are arranged on the upstream side of the transfer roller 14 and the photosensitive tram 10, and a fixing device 18, a paper ejection roller 19, and a paper ejection tray 20 are arranged on the downstream side. It is set up. The fixing device 18, which is a fixing means, is composed of a pair of fixing rollers such as heating and pressure rollers 18a and 18b, and a halogen heater is installed inside the heating roller 18a to keep its outer surface temperature constant for fixing. controlled by temperature.

Furthermore, exposure means such as a laser device 21, a polygon mirror 22, and a folding mirror 23 are arranged above the photosensitive drum 10 and the like.

That is, when the photosensitive drum 10 uniformly charged by the negative charger 11 is exposed to image light through the exposure means, an electrostatic latent image is formed on the photosensitive drum 10. The electrostatic latent image is directed toward a developing device 12 as the photosensitive drum IO rotates, and a developer (toner) is supplied by the developing device 12 to be visualized as a toner image. The toner image is directed toward the transfer roller 14 as the photosensitive drum 10 rotates, and is transferred onto the transfer paper P via the transfer roller 14. Incidentally, the photosensitive drum 10 after the transfer is cleaned of residual toner by a cleaning device 13, and is prepared for the next image formation.

On the other hand, the transfer paper P in the paper feed cassette 15 is transferred to the paper feed roller 16.
After the photosensitive drum 1 is taken out one by one, the photosensitive drum l is sent to the registration roller 17, and the timing is matched by the registration roller 17.

sent to. When the toner image is transferred onto the transfer paper P via the transfer roller 14, the transfer paper P is sent to the fixing device 18, heated by the fixing device 18, and held between the pressure rollers 18a and 18b. At the same time, the toner image is heated to a predetermined temperature and pressurized to be fixed. The transfer paper P on which the fixing operation has been completed is stacked on the paper discharge tray 20 via the paper discharge roller 19.

Note that a scanner motor 24 is installed as a drive source in the main body of the apparatus.
The scanner motor 24 rotates the polygon mirror 22 of the exposure means, and the main motor 25 rotates the other rotating equipment (the photosensitive drum 10, the transfer roller 14, the developing device). 12 (developing roller 12a, paper feed roller 16, registration roller 17° heating, pressure rollers 18a, 18b, etc.) are rotationally driven.

Now, the photosensitive tram 1O1-forming charger 11. developer 12,
An image forming device such as the cleaning device 13 is incorporated into a cartridge container 30a, forming a process cartridge 30 that is integrally attached to and detached from the main body of the apparatus.

The process cartridge 3o is filled with toner having different particle sizes, and by replacing the process cartridge 30, it is possible to form various images with different print densities.

For this reason, in this image forming device IIc, as shown in FIG. 2, a DC controller 26 is provided, and the
The C controller 26 can change the rotation speed of the polygon mirror 22, the frequency of the image clock of the laser device 21, the size of the laser beam, and process conditions (process speed, fixing temperature, etc.). As shown in FIG. 3, a light shielding plate 26 having a diamond-shaped aperture hole (for determining the size of the laser beam) is provided on one side of the laser device i21, and a light shielding plate 26 is provided on one side of the laser device i21. After the image light L) passes through the aperture hole of the light shielding plate 26 and its size is determined, it is exposed onto the photosensitive drum 10 via the polygon mirror 22 and the folding mirror 23. Therefore, by rotating the light shielding plate 26 by a predetermined amount using the light shielding plate rotation motor 27 (see FIG. 2), the aperture hole for the laser device 21 can be switched, and the size of the laser beam can be freely changed. It is now possible to do so.

Further, as shown in FIG. 2, an optimum condition table 28 is provided on one side of the DC controller 26, and according to the optimum condition table 28, the polygon mirror 22 is rotated to meet the specifications regarding the printing density of the process cartridge IO. The number etc. is determined.

Furthermore, a second
As shown in the figure, a detecting means 31 consisting of a transmitting section 32 and a detecting section 33 is provided, and a detecting section 33 on the side of the main body l of the apparatus is detected via the transmitting section 32 provided in the process cartridge 30. 30 types are detected, and this signal is sent to the optimum condition table 28 via the DC controller 26.

Specifically, as shown in FIG. 4, a claw-shaped protrusion 40 is provided on the front side of the cartridge container 30a as the transmission section 32, and three first projections 40 are provided on the main body side as the detection section 33. Second
, third plate switches 41A, 41B, and 41C are provided. When the process cartridge 30 is installed in the apparatus main body l, the plate spring portion 41a that engages with the protrusion 40 is extended, and the switch portion 41b is turned on.

For example, process cartridge 30 (fourth
(see figure) is installed in the device body 1, and if the protrusion 40 or the switch part 41b of the first and third plate spring switches 41A and 41C are turned on, this signal is sent to the DC controller 26.
It is sent to the optimum condition table 28 via the process cartridge 30, and it is determined whether the process cartridge 30 has a print density of 300 dpi. Then, based on this optimum condition table 28, the image clock frequency (for example, 1.8638] 3 MHz, the rotation speed of the polygon mirror 22 (for example, 5565., !1 rpm), and the laser The beam size (for example, 90 x 110 gm) and the fixing temperature (for example, 165°C) are determined, and the laser device 21. The signal is transmitted to the scanner motor 24, the light-shielding plate rotation motor 27, and the fixing device 18, and an image is formed under the optimum conditions for a print density of 300 dpi.

Further, for example, a process cartridge 30 for printing density 600 dpi is installed in the apparatus main body 1, and its protrusion 40
Similarly, if the switch portions 41b of the first and second leaf spring-equipped switches 41A and 41B are turned on, the optimal condition chifur 28 is also set.
The frequency of the image clock (7,455252 MHz) and the rotation speed of the polygon mirror 22 (11131.6 rpm) are suitable for a printing density of 600 dpi.
, the size of the laser beam (50 x 60 m), and the fixing temperature (in this case, 165°C) are determined, and the equipment on the main body 1 of the device also operates according to these conditions to achieve a print density of 60°C.
Images are formed under conditions optimal for 0 dpi.

Note that these process cartridges 30 for print density of 300 dpi and 600 dpi have a toner particle size of 1
2uLm and 6JAm are different, but the other conditions are exactly the same, so there is no need to change the process speed or the like.

As described above, since the detection means 31 for detecting the type of the process cartridge 30 is provided on the process cartridge 30 and the apparatus main body 1 side, and the DC controller 26, the optimum condition table 28, etc. are provided on the apparatus main body 1 side, Process cartridge 30 with different specifications regarding printing density
Even if the image forming apparatus is installed in the main body of the apparatus, the image forming apparatus will automatically form an appropriate image.

Next, a second embodiment of the present invention will be described with reference to FIGS. 2, 5, and 6. Components having the same functions as those in the first embodiment are designated by the same reference numerals, and their explanations will be omitted.

This embodiment relates to the case where a postcard-sized process cartridge 30 is installed in the main body 1 of the apparatus, as shown in FIG. Since the width of the photosensitive portion of the photosensitive tram 10 of this process cartridge 30 is only the width of a postcard size, when this process cartridge 10 is installed in the apparatus main body 1, all image data of letter size or smaller is compressed to postcard size. A printing function is provided on the main body l side of the apparatus. In other words, the original image data is A4 size (201x287mm) and the printing density is 300.
The items in dp i are postcard size (100X14
3mm) and is printed as an image with a printing density of 600dpi.

Conventionally, a postcard-sized process cartridge 30 was installed in the main body of the apparatus, and when the image data was postcard-sized, the host computer had no choice but to process the source image data. The conditions of the device main body 1 (polygon mirror 2) are determined by the printer's manual.
2, the frequency of the image clock of the laser device 21,
However, in this embodiment, this is automatically done.

Then, the process cartridge 30 exclusively for postcards is installed in the apparatus main body 1, and the protrusion 40 or the switch part 41b (fourth
(see figure), this signal is sent to the DC controller 2.
6 to the optimum condition table 28, and this process cartridge 30 is recognized as being exclusively for postcards.

For example, if the image data that is the source data is A4 size with a print density of 300 dpi, the optimum condition table 28 determines the image clock frequency (7,455252 MHz) suitable for the print density of 600 dpi.
Rotation speed of polygon mirror 22 (11131,6 rpm)
, laser beam size (90xllOILm), and fixing temperature (175°C) are determined, and the equipment on the main body side of the device also operates according to these conditions to form a Hegaki-sized image under the optimal conditions for printing density of 600 dpi. will be done.

As described above, even when the process cartridge 30 for postcards is used, an image with a necessary print density is automatically formed according to the image data. Therefore, this embodiment has the advantage that even if the DC controller 26 side does not have an enlargement/reduction function, enlarging/reducing printing is possible using only the functions of the apparatus main body l.

In addition, FIG. 6 shows the state when an image K (shaded area) is formed on A4 size transfer paper P using the process cartridge 30 exclusively for postcards. I understand that it will be printed in a reduced size.

(Effects of the Invention) As is clear from the above description, according to the present invention, the detection means detects the type of process cartridge related to print density, and the control means automatically switches the conditions on the apparatus main body side based on the detection signal. As a result, proper images with different print densities can be automatically formed without any erroneous operation when replacing the process cartridge.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of the image forming apparatus according to the first embodiment, FIG. 2 is a control block diagram showing the control operation of the image forming apparatus, and FIG. 3 is a perspective view of the area around the exposure means of the image forming apparatus. , FIG. 4 is a perspective view showing a state in which a process cartridge is being installed in the main body of the image forming apparatus, and FIG. 5 is a process exclusively for postcard size installed in the image forming apparatus according to the second embodiment. A perspective view of the cartridge, FIG. 6 is a diagram showing the size and position of an image when an image is formed on A4 size transfer paper using the same process cartridge, and FIG. 7 is a diagram for explaining the prior art. l...Device main body, 10-...Photosensitive tram (image carrier)
, 12--Developer (developing means), 21--Laser device, 22--Polygon mirror, 26--DC controller (control means), 30--Process cartridge, 31--Detecting means .

Claims (1)

[Claims] In an image forming apparatus in which a process cartridge having at least an image carrier and a developing means is removably installed in the apparatus main body, it is detected when a process cartridge with different specifications regarding printing density is installed in the apparatus main body. Based on the detection means and the signal from the detection means, the rotation speed of the polygon mirror on the device main body side, the frequency of the image clock of the laser device, the laser beam size, and the process conditions are automatically adjusted to match the specifications regarding printing density on the process cartridge side. An image forming apparatus characterized in that it is provided with a control means for switching.