JPH05281798A - Cartridge and image forming device - Google Patents

Abstract

PURPOSE:To provide a cartridge excellent in assemblability and handlability. CONSTITUTION:The cartridge 4 is constituted by covering a photosensitive drum 4a and a developing means 4c with a cartridge cover 4e, and a constitution that an elastic member pressing the developing means 4c toward the photosensitive drum 4a is provided in the inner surface of the cartridge cover 4e, is adopted. When the cartridge cover 4e is fitted, the developing means 4c toward the photosensitive drum 4a by the elastic member, and they are surely positioned. On the other hand, the elastic member is not exposed outside the cartridge cover 4e, so that the cartridge 4 has excellent handlability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cartridge and an image forming apparatus used for forming an image in a copying machine or a printer using an electrophotographic system.

[0002]

2. Description of the Related Art An image forming apparatus such as a copying machine forms a latent image by selectively exposing a uniformly charged image carrier to form a latent image, and the latent image is visualized with toner. Image recording is performed by transferring the toner image to the recording material. In such an apparatus, the toner has to be replenished each time it runs out, but this toner replenishment work is not only troublesome, but it may be contaminated. In addition, maintenance of each member can be performed only by a specialized service person, which often causes inconvenience to the user.

Therefore, as shown in FIG. 45, the photosensitive drum 100, which is the image carrier, the charging device 101, the developing device 102, the cleaning portion 103 and the like are integrally formed into a cartridge so that the user can carry out the cartridge. In order to replenish toner and replace parts such as the photosensitive drum that have reached the end of their life, the maintenance of the device has been put into practical use.

[0004]

However, in the cartridge and the image forming apparatus used for the image formation, the handling property of the cartridge, the treatment of the toner as the developer,
There are the following problems in terms of the conveyance processing of the recording material.

(1) Since the sleeve 102a of the developing device 102 and the photosensitive drum 100 must be positioned with a minute gap therebetween, conventionally, the developing device 102 is rotatably mounted about the shaft 102b. At the same time, after covering with the cartridge cover 104, the tail protrusion 102c of the developing device 102 protruding from the hole provided in the cover 104 is replaced with the protrusion 10 of the cover 104.
By attaching the spring 106 to 5 and pulling it,
Was biased toward the photosensitive drum 100 and positioned.

However, in the above structure, the spring 106 and the protrusions are exposed to the outside of the cartridge cover 104, which makes it inconvenient to handle the cartridge. Further, when the cartridge cover 104 is removed and the developing device 102 is replaced. Had to remove all the springs 106, so there were problems such as poor operability.

(2) Further, by making the cartridge as a cartridge and making it replaceable as described above, the capacity of the waste toner container of the cleaning unit 103 becomes equal to the amount of the waste toner when all the toner in the developing device 102 is used. You can set it, but the developing device
If the amount of toner in 102 is increased and the number of printable sheets is increased, the waste toner container must be upsized, and as a result, the entire cartridge is upsized and becomes difficult to handle. This is a more serious problem in a color image forming apparatus having a plurality of developing devices because the amount of the waste toner increases.

(3) In the cartridge,
In order to rotate the photosensitive drum 100, it is necessary to connect the gear provided on the rotary shaft of the photosensitive drum when the cartridge is loaded and the drive gear of the apparatus main body. Therefore, when loading the cartridge, it is necessary for the operator to perform connection while checking the meshing state of the gears, which causes a problem that the loading operability deteriorates.

(4) Further, as shown in FIG. 46, the cartridge 10 is provided with an opening / closing cover 10 which can be opened / closed with respect to the apparatus main body 107.
If you move it together with the 8
When opened, the cartridge is tilted greatly. At this time, the toner in the developing device 102 moves to the sleeve 102a side, the toner is clogged and is not normally supplied to the sleeve 102a, and the scattered toner accumulated between the developing devices 102 is located below. There is a problem such as being mixed in. This is because non-magnetic one-component toner, which is often used when a multi-color image forming apparatus adopts a cartridge system, has a great influence on the image.

(5) When a color image is to be further formed, the leading end of the recording material fed by the feeding means 109 is held by the transfer drum 110, and the drum 110 is rotated to make the first recording material on the recording material. The image is sequentially transferred from the second color to the third color, but when the first color image is transferred, the recording material is being fed from the feeding means 109, and thus the second color is transferred. Subsequent transfer images are likely to be displaced. Therefore, conventionally, the feeding speed of the recording material by the feeding means 109 is set to be slightly higher than the rotational peripheral speed of the transfer drum 110, and the recording material fed by the feeding means 109 is set to the transfer drum 110. I try not to be pulled by.

However, since the transfer drum 110 has an elastic body such as a foam on the outer periphery and there is a variation in the outer diameter, it is necessary to increase the feeding speed of the feeding means 109 including this variation. is there. Therefore, the feeding means 109 and the transfer drum
At 110 intervals, the slack of the recording material increased, and jams (paper jams) sometimes occurred. Further, in order to prevent this, the final feeding roller pair of the feeding means 109 and the transfer drum 11
It is also possible to prevent the jamming due to the looseness of the recording material by increasing the distance from the recording material grip portion of 0, but the length of the path of the recording material becomes large and the apparatus becomes large. Issues such as occur.

(6) Further, in the color image forming apparatus, as shown in FIG. 47, the photosensitive drum 100 and the transfer drum are
In order to rotate 110 and 110 in synchronization, a motor gear 111a of a drive motor (not shown), a drive gear 111b attached to the side end of the photosensitive drum 100, and a driven gear 111c attached to the side end of the transfer drum 110 are meshed in order. Then, the drive motor is driven so that the photosensitive drum 100 and the transfer drum 110 rotate in synchronization. Even if a load fluctuation occurs in the rotation of the transfer drum 110 by constantly engaging the viscous gear 112 having a constant viscous load with the driven gear 111c, the tooth surface of the driven gear 111c is always the one tooth surface of the drive gear 111b. So that it can be pressed against. This allows the drive gear
This is to prevent speed fluctuation due to backlash between 111b and driven gear 111c.

However, if the viscous gear 112 is always meshed with the gear 111c of the transfer drum 110 in this way, the user can easily rotate the transfer drum 110 by free rotation manually when the recording material is jammed. Transfer drum
There is a problem that it takes time to remove the recording material uncertainly wrapped around 110.

(7) Further, in the color image forming apparatus, in the developing process of each color, there is a difference in toner and the photosensitive drum.
Since the development densities do not become the same even under the same development conditions due to the gap difference between 100 and the sleeve 102a of the developing device 102, the density of the pre-developed image is detected by the density detection sensor 113 as shown in FIG. Each color is developed to have the same density. Further, in order to correct the sensitivity of the photosensitive drum 100, a protruding piece 114 showing the sensitivity level of the photosensitive drum 100 is provided in the cartridge, and the combination of the unevenness of this piece 114 and the switch 115 provided on the apparatus main body side are used to form
Sensitivity of 100 was detected.

However, the protruding piece 114 is attached to the cartridge.
Since the assembling of the switch deteriorates the assembly, the combination of the unevenness is limited to about three types in terms of the assembling property and the cost, and the switch for detecting only the sensitivity is provided on the device body side.
Since 5 had to be provided, it was a factor of cost increase.

(1) The present invention is to solve the above-mentioned problems of the prior art, and an object thereof is to provide a cartridge which is easy to assemble and handle and an image forming apparatus using the cartridge.

(2) Another object of the present invention is to provide a cartridge capable of cleaning waste developer without increasing the size of the cartridge and an image forming apparatus using the cartridge.

(3) Another object of the present invention is to provide an image forming apparatus having a good cartridge operability.

(4) Still another object is to provide an image forming apparatus in which the developer in the cartridge is not clogged even if the opening / closing cover is opened when the cartridge is moved together with the opening / closing cover. is there.

(5) Still another object is to provide an image forming apparatus in which slack of a recording material is properly controlled when the recording material is fed from a feeding means to a transfer rotary member. It is a thing.

(6) Another object is to provide an image forming apparatus capable of removing the load on the recording material by the feeding means when the transfer rotator is wound around the recording material to rotate. ..

(7) Still another object is to provide an image forming apparatus capable of easily manually rotating a transfer rotary member during jam processing.

(8) Still another object is to provide an image forming apparatus capable of detecting the density of a transferred image by reducing the number of parts.

[0024]

In order to achieve the above object, a typical cartridge of the present invention has a structure in which an image carrier is positioned with a certain gap with respect to the image carrier. Developing means for developing an image formed on the image carrier, a cartridge cover mounted so as to cover the image carrier and the developing means, an elastic member provided on the inner surface of the cartridge cover, and the cartridge cover mounted By doing so, the developing means is urged toward the image carrier through the elastic member.

A typical image forming apparatus has an image carrier, a developing means for developing the image formed on the image carrier, and a recording material wound around the peripheral surface and rotated. The transfer rotary member is provided between the transfer rotary member, a feeding unit for feeding the recording material to the transfer rotary member, the feeding unit, and a position where the transfer rotary member receives the recording material. It is constituted by slack detecting means for detecting slack of the recording material, and control means for changing the feeding speed of the recording material by the feeding means in response to a signal from the slack detecting means. As

[0026]

In the cartridge having the above construction, when the cartridge cover is loaded, the elastic member on the inner surface of the cover biases the developing means toward the image carrier, so that the image carrier and the developing means can be easily positioned. Done

Further, in the image forming apparatus having the above-mentioned structure, the feeding speed of the recording material changes in accordance with the slack detection signal from the slack detecting means, so that the recording material can be accurately prevented from being excessively slackened. It is possible to feed the transfer rotary member.

[0028]

【Example】

[First Embodiment] Next, an image forming apparatus according to a first embodiment of the present invention will be described with reference to the drawings.

{General Description of Image Forming Apparatus} First, the general structure of the image forming apparatus will be briefly described. 1 is an explanatory view of the overall structure of a laser beam printer which is one mode of the image forming apparatus, FIG. 2 is an explanatory view of the structure of a process cartridge, and FIG. 3 is an external perspective view of the process cartridge.

This device, as shown in FIG.
The recording material 2 fed from the recording medium 2 is wound around the transfer drum 3, and a color image is formed by a multiple transfer system in an image forming section in which the process cartridge 4 and the black developing unit 5 are loaded on the recording material 2. Then, the recording material 2 is conveyed to the fixing section 6 to fix the color image on the recording material 2, and is discharged by the discharge roller pair 7 to the discharging section 8 in the upper part of the apparatus.

The process cartridge 4 and the black developing unit 5 are separately attachable to and detachable from the apparatus main body 9 as described later.

The exposure of the image forming unit is performed by the scanner unit 10.
Sent from. That is, the image signal is the laser diode 10
When given to a, the laser diode 10a irradiates the polygon mirror 10b with image light corresponding to the image signal. The polygon mirror 10b is rotated at a high speed by a scanner motor 10c, and the image light reflected by the polygon mirror 10b is irradiated from the exposure section of the process cartridge 4 via the imaging lens 10d and the reflection mirror 10e to selectively image the image carrier. It is configured to be exposed to.

Next, the structure of each part of the image forming apparatus will be sequentially described in detail. {Feeding unit} The feeding unit 1 feeds the recording material 2 to the image forming unit, and the paper feed cassette 1a containing a plurality of recording materials 2 is loaded in the inner bottom portion of the apparatus main body 9. .. During image formation, the pickup roller 1b is driven and rotated according to the image forming operation to separate the recording materials 2 in the cassette 1a one by one, and are fed by the feed roller 1c1 and the retard roller 1c2 and guided by the guide plate 1d. Then, the pair of registration rollers 1e1 and 1e2 are fed, and the pair of registration rollers 1e1 and 1e2 are driven in synchronization with the image forming timing to feed the recording material 2 to the transfer drum 3.

The guide plate 1f shown in FIG. 1 has a cassette (not shown) mounted on the outer bottom of the apparatus body 9 and has an insertion opening 1g.
Is for guiding the recording material 2 supplied from the feeding roller 1h, and the feeding roller 1h is for supplying the recording material 2 manually fed from the insertion opening 1i.

{Transfer Drum} The transfer drum 3 winds the fed recording material 2 and rotates in the arrow direction of FIG. 1 in order to transfer each color toner onto the recording material 2.

The transfer drum 3 according to this embodiment has a diameter of about 140.
An elastic layer 3b such as sponge or rubber is formed on the outer circumference of an aluminum cylinder 3a of mm, a conductive layer 3c is formed on the outer circumference, and a dielectric layer 3d is formed on the outermost circumference. The transfer drum 3 rotatably supports a rotary shaft 3e on the main body 9 of the apparatus, and transmits a driving force of a drive motor to a gear (not shown) fixed to the rotary shaft 3e, so that the transfer drum 3 can be operated in accordance with an image forming operation. It is configured to rotate in the direction of the arrow 1.

Further, a gripper 3f is provided at a predetermined position on the outer circumference of the transfer drum 3 so as to grip the leading end of the fed recording material 2. Furthermore, electrostatic attraction roller 3g
Is provided on the outer periphery of the transfer drum 3 so as to be able to come into contact with and separate from the outer periphery of the transfer drum 3. The recording material 2 is pressed against the outer periphery of the transfer drum 3 so as to be sandwiched between the electrostatic attraction roller 3g and the transfer drum 3, and the electrostatic attraction roller By applying a voltage between 3g and the conductive layer 3c on the outer periphery of the transfer drum, an electric charge is induced in the recording material 2 that is a dielectric and the dielectric layer 3d of the transfer drum 3, and the recording material 2 is transferred to the transfer drum. 3 is configured to be electrostatically attracted to the outer circumference.

The method of attracting the recording material 2 to the transfer drum 3 is not limited to the electrostatic attraction, but may be a suction method using air.

{Process Cartridge} Next, the process cartridge will be described. It has at least an image carrier and a developing means for developing the image formed on the image carrier. As an example thereof, for example, the image carrier and the developing means are integrated into a cartridge, which can be attached to and detached from the main body of the image forming apparatus. Alternatively, in addition to the image carrier and the developing means, a charging means or a cleaning means as a process means is integrated into a cartridge, which is detachably mountable to the main body of the image forming apparatus. Alternatively, an image carrier, a charging unit as a process unit, a developing unit,
The cleaning means is integrated into a cartridge, which can be attached to and detached from the main body of the image forming apparatus.

The process cartridge 4 of this embodiment is shown in FIG.
Further, as shown in FIG. 2, the charging means 4b, yellow, magenta, around the electrophotographic photosensitive drum 4a which is an image carrier,
Three developing means 4c respectively accommodating three color toners (developing agents) Y, M and C of cyan, and a cleaning means 4
d is arranged, and these are covered with a cartridge cover 4e to integrally form a cartridge, which is configured to be attachable to and detachable from the apparatus main body 9.

Next, each part of the process cartridge 4 will be individually described.

(Photosensitive Drum) The photosensitive drum 4a according to the present embodiment is constituted by applying an organic photoconductive layer 4a2 to the outer peripheral surface of an aluminum cylinder 4a1 having a diameter of about 70 mm, and rotating shaft 4a3.
Is rotatably supported by the cartridge cover 4e.
Further, a gear 4a4 fixed to one end of the rotary shaft 4a3 (see FIG.
By transmitting a driving force of a driving motor (not shown) to the photosensitive drum 4a, the photosensitive drum 4a is rotated in the arrow direction of FIG. 1 according to the image forming operation.

(Charging Means) The charging means 4b is disclosed in JP-A-63-14.
A so-called contact charging method as shown in Japanese Patent No. 9669 is used, in which a conductive roller is brought into contact with the photosensitive drum 4a,
The surface of the photosensitive drum 4a is uniformly charged by applying a voltage to the conductive roller.

The process cartridge 4 is provided with an exposure section 4f for irradiating the photosensitive drum 4a charged by the charging means 4b with the image light from the scanner section 10 to form a latent image. ..

(Developing Means) In order to make the latent image visible, three developing means 4c capable of developing yellow, magenta and cyan are arranged.

As shown in FIG. 2, each of the three developing means 4c is provided with a toner feeding mechanism as shown in Japanese Patent Application No. 3-268646 at the bottom of a container 4c1 for storing toner. That is, a plate member having a groove portion or a hole portion surrounding the toner on the surface facing the bottom surface of the container is provided so as to be slidably contactable with the bottom surface of the container 4c1. Is configured to move in sliding contact with the bottom surface of the container, and to move apart in the return path to send the toner to the tip of the container. Further, an application roller 4c3, a blade 4c4 and a sleeve 4c5 which is a developer carrying member are attached to the tip of the container to which the toner is fed by the feeding mechanism 4c2. Then, yellow, magenta, and cyan toners Y, M, and C are stored in order from the top in the container 4c1 of the three developing means 4c.

At the time of image formation, yellow, magenta,
The developing means 4c corresponding to each color development of cyan is driven to sequentially form a visible image by the toner on the photosensitive drum 4a. That is, the toner in the container 4c1 corresponding to the color to be developed is fed to the coating roller 4c3 by the feeding mechanism 4c2, the toner is thinly coated on the outer periphery of the rotating coating roller 4c3 and the sleeve 4c5 rotated by the blade 4c4, and the toner is applied to the toner. Charge is given (triboelectric charging). With this sleeve 4c5,
By applying a developing bias between the latent image and the photosensitive drum 4a, toner development is performed on the photosensitive drum 4a according to the latent image.

The three developing means 4c are sleeves 4
The c5 and the photosensitive drum 4a are positioned so as to face each other with a minute gap (about 250 μm), and the driving force is selectively transmitted to each developing means 4c by a drive switching means (not shown). That is, in the case of forming a full-color image, first, the developing means containing the yellow toner Y is driven, and at this time, other magenta and cyan toners M,
The developing means containing C is not driven, and only the yellow toner is developed on the photosensitive drum 4a. Similarly, magenta,
The drive is switched so that the toner is developed on the photosensitive drum 4a in the order of cyan.

The sleeve 4c5 of each developing means 4c is connected to a high-voltage power source for developing each color provided in the apparatus main body 9, and a voltage is selectively applied for each color development.

(Positioning of Sleeve with respect to Photosensitive Drum) As shown in FIG. 4A, the sleeve 4c5 of the developing means 4c is positioned with respect to the photosensitive drum 4a by positioning members 4g on both sides in the rotation axis direction of the photosensitive drum 4a. It is attached to the rotary shaft 4a3, and is attached to the positioning member 4g.
As shown in (b), 4
The individual adjusting member 4h and the sleeve abutting member 4i are attached and configured.

The adjusting member 4h is provided with an eccentric cam portion 4h2 centered on the fitting hole 4h1, and the fitting hole 4h1 is rotatably fitted to the boss 4g1 of the positioning member 4g. Further, the sleeve abutting member 4i has an arcuate abutting portion with which the sleeve 4c5 abuts, and the base 4i1 is guided by the boss 4g2 of the positioning member 4g so as to be slidable in the arrow direction of FIG. 4B. It is attached so that the edge portion 4i2 abuts the eccentric cam portion 4h2 of the adjusting member 4h. The sleeve abutting member 4i can rotate the eccentric cam portion 4h2 by rotating the adjusting member 4h to finely adjust the amount of protrusion in the direction of the arrow in FIG. 4 (b). The adjustment member 4h is prevented from rotating, and the sleeve contact member 4
Fix the bosses 4g1 and 4g2 by crushing them so that i does not move.

The arcuate contact portion of the sleeve contact member 4i fixed to the positioning member 4g as described above is shown in FIG.
As shown in (b), the positioning member 4g is centered around the support shaft 4c6.
The developing means 4c rotatably attached to the above is urged in the arrow direction by its own weight and a pressure member (not shown),
The shaft portion of the sleeve 4c5 is butted against the arcuate contact portion.
This allows the photosensitive drum 4a and the sleeve 4c5 to be positioned so as to have a minute gap δ.

As shown in FIG. 4 (b), four sleeve abutting members 4i are fixed to the positioning member 4g, three of which are attached to the three developing means 4c of the process cartridge 4. The sleeve 4c5 is brought into contact with and positioned, and the remaining one is brought into contact with and positioned with the sleeve of the black developing unit 5.

(Cartridge cover) The photosensitive drum 4
A, the charging unit 4b, and the developing unit 4c are covered with a cartridge cover 4e. This cartridge cover 4e
Is made of synthetic resin and has a case-like shape having an opening 4e1 at the front, as shown in FIG. A shaft hole 4e2 into which the rotary shaft 4a3 of the photosensitive drum 4a is fitted is formed on both wall surfaces,
A shaft hole 4 into which the rotary shaft of the sleeve 4c5 of the developing means 4c is fitted.
A shaft hole 4e4 into which the rotation shaft of e3 and the coating roller 4d3 is fitted is provided.

Further, three leaf springs 13 which are elastic members for urging the container 4c1 of the developing means 4c forward are attached to the rear portion of the inner surface of the cover 4e.

The developing means 4 is provided with the cartridge cover 4e.
In order to cover c, both side walls made of synthetic resin are elastically deformed to open the opening 4e1, three developing means 4c are inserted, and the respective rotary shafts are fitted to the respective shafts 4e2, 4e3, 4e4, As shown in FIG. 6, the cartridge cover 4e is attached.

When the cartridge cover 4e is mounted, as shown in FIG. 6, the leaf spring 13 inside the cover presses the containers 4c1 of the respective developing means 4c to urge the developing means 4c toward the photosensitive drum 4a. As a result, the sleeve 4c5 is pressed against the sleeve abutting member 4i, so that the developing means 4c can be more reliably positioned with respect to the photosensitive drum 4a. At this time, a reaction force due to the urging of the leaf spring 13 causes a force to push down the cartridge cover 4e,
The cover 4e is locked by a meshing portion 4e5 at the top.

As described above, since the developing means 4c can be positioned with respect to the photosensitive drum 4a only by mounting the cartridge cover 4e, the process cartridge 4 can be easily assembled and a spring or the like is provided outside the cartridge cover 4e. Since it does not project, it is easy to handle.

(Protective Cover) The developing means 4c positioned with respect to the photosensitive drum 4a and the toner visualized on the photosensitive drum 4a by the black developing unit 5 are transferred onto the recording material 2 on the transfer drum 3. Since the image is transferred, the photosensitive drum 4 a is exposed during image formation and faces the transfer drum 3. However, since the process cartridge 4 is attached to and detached from the apparatus main body 9, if the photosensitive drum 4a is exposed when the process cartridge 4 is removed from the apparatus main body 9, dust or the like is attached or external light is emitted. It is exposed to water and deteriorates. Therefore, in this embodiment, as shown in FIG. 2, the cartridge cover 4e is provided with a protective cover 4j that can be opened and closed.
Is provided.

This protective cover 4j is centered around the shaft 4j1 as shown in FIG.
The first cover 4j2 that can be opened and closed as shown by the solid and broken lines
And a second cover 4j5 which is attached to an arm 4j4 rotatable about a shaft 4j3 and slidable to the state of the broken line in FIG.
It consists of and.

The first cover 4j2 and the second cover 4j5
Are biased in the closing direction by springs or the like not shown, and when the process cartridge 4 is removed from the apparatus main body 9, the process cartridge 4 is closed as shown by the solid line in FIG. It won't hit. Then, the process cartridge 4 is attached to the apparatus main body 9
When it is loaded on the transfer drum 3, the first cover 4j2 and the second cover 4j5 are opened by a mechanism (not shown) as shown by the broken line in FIG. 2, and the photosensitive drum 4a is exposed.
Is configured to face.

(Cleaning Means) The cleaning means, after the toner visualized on the photosensitive drum 4a by the developing means 4c of the process cartridge 4 and the developing means of the black developing unit 5 described later is transferred to the recording material 2, The toner remaining on the photosensitive drum 4a is cleaned. In this embodiment, the cleaning means 4d is shown in FIGS.
, The lower waste toner container 4d1 and the upper waste toner container 4
The upper waste toner container 4d2 is detachably accommodated in the lower waste toner 4d1.

The toner remaining on the photosensitive drum 4a is scraped off by the blade 4d3 as the photosensitive drum 4a rotates, and is stored in the lower waste toner container 4d1. The waste toner contained in the lower waste toner container 4d1 is fed by the feed roller 4 having a sponge layer such as urethane which rotates in the direction of the arrow in FIG.
It is stored in the upper waste toner container 4d2 by d4. When the waste toner in the upper waste toner container 4d2 is full, the toner container lid 4d7 is removed as shown in FIG. 8, the upper waste toner container 4d2 is removed from the lower waste toner container 4d1, and this is replaced. ing.

The upper waste toner container 4d2 is provided with a backflow preventing sheet 4d5 for preventing the waste toner from returning to the lower waste toner container 4d1 and a scraper 4d6 for scraping off the waste toner carried on the feed roller 4d4. The waste toner contained in the upper waste toner container 4d2 is prevented from returning to the lower waste toner container 4d1 due to vibration or the like. Therefore,
When replacing the upper waste toner container 4d2, the waste toner does not spill.

By replacing the upper waste toner container 4d2 when the waste toner is full, the waste toner is removed from the waste toner container 4d1, 4d2 even if the capacity of the waste toner container 4d1, 4d2 is reduced. Overflow can be prevented, and as a result, the cartridge 4 can be downsized, and the image forming apparatus in which the cartridge 4 is loaded can be downsized.

{Black Developing Unit} The black developing unit 5 is for developing black on the photosensitive drum 4a, and its construction is similar to that of the process cartridge 4 in the container 5a for storing black toner as shown in FIG. A toner feeding mechanism 5b and a rotating member 5g are provided, and a coating roller 5c, a blade 5d, and a developing unit are provided at the tip of the container to which the black toner is fed by the feeding mechanism 5b and the rotating member 5g, similarly to the developing means of the process cartridge 4 described above. A sleeve 5e, which is an agent carrier, is attached and configured.

As a result, the black toner in the container 5a is fed to the coating roller 5c by the feeding mechanism 5b and the rotating member 5g, and a thin layer of toner is applied to the outer periphery of the rotating coating roller 5c and the sleeve 5e rotated by the blade 5d. , Charge the toner. This sleeve 5e
Is rotated in synchronism with the photosensitive drum 4a on which the latent image is formed, so that black development is performed on the photosensitive drum 4a.

The black developing unit 5 is constructed separately from the process cartridge 4, and the process cartridge 4 and the black developing unit 5 are independent of each other and are the main bodies 9 of the apparatus.
It is configured to be removable.

Since the black toner is used more frequently than the other color toners, the toner container 5a of the black developing unit 5 has a larger capacity than the toner container 4c1 of the process cartridge 4.

[Fixing Section] The fixing section 6 is for fixing the image formed on the recording material 2 wound around the transfer drum 3 by the process cartridge 4 and the black developing unit 5, and is driven as shown in FIG. Rotating drive roller 6
a and a fixing roller 6b which is in pressure contact with the recording material 2 and applies heat and pressure to the recording material 2. That is, the recording material 2 separated from the transfer drum 3 is conveyed by the drive roller 6a when passing through the fixing portion 6, and heat and pressure are applied by the fixing roller 6b. As a result, the image forming toner is fixed on the recording material 2.

A cleaning member 6c is in contact with the fixing roller 6b, and the toner attached to the roller 6b is removed by the cleaning member 6c.

{Loading of Process Cartridge and Black Developing Unit in Apparatus Main Body} Next, a structure for loading the process cartridge 4 and the black developing unit 5 in the apparatus main body 9 will be described.

As shown in FIGS. 9 and 11, an upper opening / closing cover 12 is attached to the main body 9 of the apparatus so as to be openable / closable about a shaft 11, and is also rotatable about the shaft 11 to hold a process cartridge. A frame 14 and a black developing unit holding frame 15 are attached.

The process cartridge holding frame 14
Has a U-shaped cross section, and a hook mechanism 16 for supporting both ends of the process cartridge 4 is provided on both side walls. The process cartridge 4 is configured to be loaded by engaging both ends of the rotary shaft 4a3 of the photosensitive drum 4a with the hook mechanism 16. The process cartridge 4 is positioned and fixed to the apparatus main body by a positioning mechanism (not shown) when the rotary shaft 4a3 is locked and loaded in the hook mechanism 16.

Although not shown in FIG. 9, the construction in which the black developing unit 5 is loaded in the holding frame 15 is similar to the construction in which the process cartridge 4 is loaded in the holding frame 14.

{Posture of Process Cartridge and the Like When Opening / Closing Cover} The postures of the process cartridge 4 and the black developing unit 5 when the open / close cover 12 is opened / closed will be described.

As shown in FIG. 9, a gear 17 having a rotation center on a coaxial extension line with the rotation shaft 4a3 of the photosensitive drum 4a is fixed to the cartridge cover 4e, and a belt 18a is attached to the holding frame 14 by a belt 18a. Connected pulley gears 18b and 18c are provided, one pulley gear 18b meshes with the gear 17 of the loaded process cartridge 4, and the other pulley gear 18c meshes with a gear 19 fixed to the shaft 11.

Therefore, as shown in FIGS. 10 (a) and 10 (b), when the opening / closing cover 12 is opened and the holding frame 14 also rotates integrally with the opening / closing cover 12 in the direction of the arrow, the rotation thereof is the pulley gear 18b. , 18c and a gear 17 are transmitted to the process cartridge 4, and the cartridge 4 is connected to the shaft 4a3.
To maintain the posture substantially the same as the state in which the open / close cover 12 is closed (the state in FIG. 9). The gear 17,
The gear ratios 18b, 18c and 19 are set according to the rotation angle of the process cartridge 4 so that the cartridge 4 maintains a substantially horizontal state when the opening / closing cover 12 is opened.

Although not shown in FIG. 10, the holding frame 15 holding the black developing unit 5 is also provided with the same gear mechanism as described above. When the holding frame 15 is integrally opened with the opening / closing cover 12, the black frame is opened. The developing unit 5 is rotated to maintain the substantially horizontal state as when the opening / closing cover 12 is closed.

As described above, the process cartridge 4 and the black developing unit 5 open the open / close cover 12, and the cover 12
Even when it moves upward together with this, the toner in the developing means does not move and become clogged because the opening / closing cover 12 is configured to maintain substantially the same horizontal state as the closed state.
Therefore, at the time of image formation, the toner is accurately supplied from the sleeve of the developing means to the photosensitive drum 4a, and high-quality image formation is performed.

{Detachment of process cartridge, etc.} As shown in FIG. 9, the upper opening / closing cover 12 has two hooks 20a, 20a.
b and slide levers 21a and 21b are provided. When the opening / closing cover 12 is closed, the upper hook 20a is locked to the process cartridge holding frame 14 and the lower hook 20b is locked to the black developing unit holding frame 15. Has been done.

Therefore, when the open / close cover 12 is opened with the slide levers 21a, 21b slid to release both the upper and lower hooks 20a, 20b, as shown in FIG. 11 (a), only the open / close cover 12 is opened. Opens upwards. As a result, the process cartridge 4 can be attached and detached.

The upper hook 20a is locked to the process cartridge holding frame 14, and the lower hook 20b and the black developing unit holding frame 15 are unlocked.
When opened, the process cartridge holding frame 14 is opened upward together with the opening / closing cover 12, and as shown in FIG.
The process cartridge 4 loaded in the frame 14 moves upward. As a result, the black developing unit 5 can be easily attached and detached.

When the open / close cover 12 is opened with the upper hook 20a locked to the process cartridge holding frame 14 and the lower hook 20b locked to the black developing unit holding frame 15, the open / close cover 12 and both holding frames 14, 15 is also opened upward, and as shown in FIG. 11 (c), each frame 1
The process cartridge 4 and the black developing unit 5 loaded in 4, 15 move upward. As a result, the recording material 2
Since the conveyance path of is exposed, it is possible to easily perform a jam (paper jam) process.

As described above, when the opening / closing cover 12 is opened / closed, the process cartridge 4 and the black developing unit 5 rotate so as to maintain the horizontal state.

{Structure Energizing Configuration of Process Cartridge and Black Developing Unit} Also, the process cartridge 4 and the black developing unit 5 are held by their respective holding frames.
When the cartridges 14 and 15 are loaded and the opening / closing cover 12 is closed, the process cartridge 4 and the black developing unit 5 are positioned by being biased by the biasing means 22 in the axial direction (thrust direction) of the rotation shaft 4a3 of the photosensitive drum 4a. Is configured.

As shown in FIG. 12 (a), the biasing means 22 is provided with a triangular plate member 22a on one side wall of the upper opening / closing cover 12, and this plate member 22a is shown in FIG. 12 (b). Leaf springs 22b and 22c as shown in FIG. And figure
As shown in FIG. 13 (a), when the upper opening / closing cover 12 is closed,
As shown in FIG. 13B, the leaf spring 22b biases the side surface of the process cartridge 4 and the leaf spring 22c biases the side surface of the black developing unit 5 in the arrow direction (thrust direction). As a result, the process cartridge 4 and the black developing unit 5 are pressed against one side of the respective holding frames 14 and 15 and positioned in the thrust direction.

{Engagement and Release of Engagement between the Gear Attached to the Rotating Shaft of the Transfer Drum and the Viscous Gear} Next, the transmission of the rotational force to the transfer drum 3 will be described. This is as shown in FIG. A drive gear 4a4 attached to the rotary shaft 4a3 of the photosensitive drum 4a is configured to mesh with a driven gear 3h attached to the rotary shaft 3e of the transfer drum 3, and the drive gear 4a4 is rotated by a drive motor (not shown) during image formation. The force is transmitted, and the rotational force is transmitted to the transfer drum 3 via the driven gear 3h, so that both drums 4a,
3 are configured to rotate at the same peripheral speed.

The transfer drum 3 is a gripper 3f.
The load changes due to the opening and closing of and the contact and separation of the electrostatic attraction roller 3g. Even at this time, the tooth surface of the driven gear (first gear) 3h is always pressed against one tooth surface of the drive gear 4a4 as shown in FIG. As shown, the driven gear 3h is configured to mesh with a viscous gear (second gear) 23 having a constant rotational load (viscous load in this embodiment).

The viscous gear 23, as shown in FIG.
The arm 24 is attached to one end of the arm 24 rotatable about the center 24a, and the solenoid 25 is attached to the other end of the arm 24. The solenoid 25 is configured to be turned on / off by a switch (not shown) which is interlocked with the opening / closing of the upper cover 12. When the upper opening / closing cover 12 is closed and the solenoid 25 is turned on, the arm 24 rotates clockwise around the shaft 24a, and the viscous gear 23 meshes with the driven gear 3h. Meanwhile, the upper cover 12 opens to open the solenoid.
When 25 is turned off, the arm 24 is rotated counterclockwise about the shaft 24a by the tension spring 26, the viscous gear 23 is separated from the driven gear 3h, and the meshed state of the two is released.

Therefore, since the viscous gear 23 meshes with the driven gear 3h of the transfer drum 3 at the time of image formation, the tooth surface of the driven gear 3h is geared with the gear 4a4 of the photosensitive drum 4a even if the load on the transfer drum 3 changes. The gears 4a4, 3h are always pressed against the tooth surface of the gear, and the driving force is accurately transmitted without being affected by the backlash.

On the other hand, when the upper opening / closing cover 12 is opened for jamming or the like, the viscous gear 23 is separated from the driven gear 3h and the meshing state of both gears 23, 3h is released, so that the transfer drum 3 is free. It comes to rotate. Therefore, when the recording material 2 is jammed without being accurately wound around the transfer drum 3, the user can open the upper opening / closing cover 12 and manually rotate the transfer drum 3 to freely perform the jam processing easily. Can be done.

[Image Forming Operation] Next, the operation of forming an image by the apparatus having the above-described structure will be described. The pickup roller 1b shown in FIG. 1 is rotated to move one recording material 2 in the paper feeding cassette 1a. The sheet is separated and fed to the transfer drum 3 at the image forming timing by the pair of registration rollers 1d. The transfer drum 3 rotates in the direction of the arrow in FIG. 1 and holds the front end of the recording material 2 fed by the gripper 3f and electrostatically adsorbs it on its peripheral surface.

In synchronism with the rotation of the transfer drum 3, the photosensitive drum 4a is rotated in the direction of the arrow in FIG. 1, the drum surface of the drum 4a is uniformly charged by the charging means 4b, and the scanner unit 10 causes yellow. The image is irradiated with light to form a yellow latent image on the photosensitive drum 4a.
Simultaneously with the formation of this latent image, the yellow developing means 4c of the process cartridge 4 is driven, and a voltage of substantially the same potential as the charging polarity of the photosensitive drum 4a is applied so that the yellow toner adheres to the latent image on the photosensitive drum 4a. The toner is applied to perform yellow development, and a voltage having a polarity opposite to that of the toner is applied to the transfer roller 3 to transfer the toner on the photosensitive drum 4 a to the recording material 2 on the transfer drum 3.

The magenta and cyan developing means 4c and the black developing unit 5 are not driven during the yellow development and transfer.

When the transfer of the yellow toner is completed as described above, the magenta, cyan, and black latent images are formed in the same manner and the toner is transferred in the same manner to form a color image on the recording material 2.

After the image formation, the recording material 2 is separated from the transfer drum 3 and conveyed to the fixing section 6, where the toner is fixed in the fixing section 6 and then discharged to the discharge tray 8 by the discharge roller pair 7. The image formation is completed.

{Load Releasing Structure of Feeding Means} When forming an image on the recording material 2 as described above, the tip of the recording material 2 is gripped by the gripper 3f of the transfer drum 3 in this embodiment, and When the recording medium 2 is conveyed by the transfer drum 3, the load on the recording material 2 by the feeding unit 1 is released.

The control configuration for that purpose will be described.
FIG. 15 is a block diagram of the feeding control configuration.
Is a control unit, such as CPU 27a, ROM 27b, RAM 27
c, a counter 27d.

The CPU 27a is a central processing unit, reads programs and various data from an external device such as a ROM 27b and an input device, which will be described later, and performs necessary calculations and judgments.
Various controls are performed.

The ROM 27b is a read-only memory, and stores various programs for the CPU 27a to operate, character codes, and various data necessary for dot pattern recording.

The RAM 27c is a read / write memory, and comprises a working area for temporarily storing the data instructed by the CPU 27a and operation results, a buffer area for storing various data input from an external device and the like. ..

The counter 27d counts the driving time according to the number of driving pulses when driving the feeding motor, and controls the feeding amount of the recording material 2 and the like by this.

The control section 27 turns on the detection signals from the sheet sensor 28 for detecting the presence or absence of the recording material 2 and the transfer drum sensor 29 for detecting the rotational position of the transfer drum 3 via the A / D converter 30, It is input as an off signal, and the first and second solenoids 31a and 31b, the electromagnetic clutch 32,
Further, a drive signal is output to the motor driver 33a that drives the feeding motor 33 via the I / O port 34.

As shown in FIG. 1, the sheet sensor 28 is provided on the conveyance path of the recording material 2 between the pair of registration rollers 1e1 and 1e2 and the transfer drum 3, and is normally off. Although in the state, the recording material 2 passes the position of the sheet sensor 28 and is turned on when the sensor lever 28a is pushed.

The transfer drum sensor 29 is attached to the apparatus main body 9 side, and the sensor 29 detects the detected member 29a provided on the side surface of the transfer drum 3 to detect the rotational position of the transfer drum 3. .. The gripper 3f of the transfer drum 3 and the tip of the recording material 2 are point P in FIG.
The recording material 2 is fed according to the rotation of the transfer drum 3 so as to rendezvous.

The first solenoid 31a is used for the retard roller 1
It is for separating c2 from the feed roller 1c1. As shown in FIG. 1, the rotation shaft of the retard roller 1c2 is attached to an arm 35 rotatable about one end, and the first solenoid 31a is connected to the other end of the arm 35. When the first solenoid 31a is off, the retard roller 1c2 is in pressure contact with the feed roller 1c1 by a spring or the like (not shown), but when the first solenoid 31a is on, the arm 35 rotates counterclockwise. Away from the feed roller 1c1.

The second solenoid 31b is for separating the pair of registration rollers 1e1 and 1e2. Like the retard roller 1c2, the registration roller 1e2 is attached to an arm 36 whose rotation shaft is rotatable about one end,
A second solenoid 31b is connected to the other end of the arm 36, and the pair of registration rollers 1e1 and 1e2 are in pressure contact when the solenoid 31b is off, but the arm 36 rotates clockwise when the solenoid 31b is on. The pair of registration rollers 1e1 and 1e2 rotate away from each other.

The electromagnetic clutch 32 switches and transmits the driving force of the feeding motor 33 to the pickup roller 1b.
When the clutch 32 is turned on, the driving force of the feeding motor 33 is transmitted to the pickup roller 1b, and when it is turned off, the transmission is interrupted.

The feeding motor 33 is a pulse motor which is connected to the pickup roller 1b via the electromagnetic clutch 32, and further connected to the feed roller 1c1 and the registration roller 1e1 to give a rotational force to each roller.

Next, the feeding procedure for releasing the load on the recording material 2 by the feeding means 1 when the recording material 2 is conveyed by the transfer drum 3 by the control section 27 will be described with reference to FIG. This will be described with reference to the flowchart in FIG.

In steps S1 to S3, the feeding motor 33 is driven, and the electromagnetic clutch 32 is turned on for a fixed time (t ₀ seconds from the start of feeding motor driving). As a result, the pickup roller 1b makes one rotation to separate and feed one recording material 2 in the cassette 1a. Incidentally, after the pickup roller 1b makes one rotation, the chord portion of the roller 1b becomes the recording material 2
And the pickup roller 1b is separated from the recording material 2. The recording material 2 picked up from the cassette 1a as described above is fed by the feed roller 1c1 and the retard roller 1c2.

When the leading edge of the recording material 2 is fed to the position of the sheet sensor 28, the recording material 2 moves to the sensor lever 28a.
To press, the sensor 28 turns on. When the sheet sensor 28 is turned on in step S4, the process proceeds to step S5, the driving of the feeding motor 33 is stopped, and the feeding of the recording material 2 is temporarily stopped.

Next, when the transfer drum sensor 29 is turned on in step S6, the process proceeds to step S7 and the drum sensor 29 is turned on.
The feeding motor 33 is driven to feed the recording material 2 after t ₁ seconds from the turning on of 29. As a result, the tip of the recording material 2 and the gripper 3f of the rotating transfer drum 3 rendezvous at point P in FIG. 1, and the tip of the recording material is gripped by the gripper 3f.

Next, in step S8, the first and second solenoids 31a and 31b are turned on after t ₂ seconds from the start of driving the feeding motor 33 in step S7. As a result, the roller pairs 1c1 and 1c2 and the registration roller pairs 1e1 and 1e2 are separated from each other, and the feeding force and the feeding load of the feeding means 1 on the recording material 2 are removed. At this time, the recording material 2 is held by the gripper 3f of the transfer drum 3 and wound around the surface of the drum 3.

Next, when the sheet sensor 28 is turned off in step S9, that is, when the trailing edge of the recording material 2 passes the position of the sheet sensor 28, the process proceeds to step S10 and the driving of the feeding motor 33 is stopped and In step S11, the first and second solenoids 31a and 31b are turned off to separate the roller pair 1 from each other.
The c1, 1c2 and the pair of registration rollers 1e1, 1e2 are returned to the pressure contact state, and the feeding is completed.

After the recording material 2 is held by the transfer drum 3 as described above, the recording material 2 which rotates according to the rotation of the transfer drum 3 is eliminated by eliminating the feeding force and the feeding load by the feeding means 1. Is prevented from being pulled by the feeding means 1, and color misregistration of image formation and jamming of the recording material 2 are prevented.

[Image Density Detecting Structure] The image forming apparatus of this embodiment is provided with the density detecting means for the image transferred onto the recording material 2. That is, as shown in FIG. 1, in the vicinity of the outer periphery of the transfer drum 3, the process cartridge 4
A density sensor 37 for detecting the density of an image is provided near the cleaning means 4d of the cartridge 4 when the cartridge is loaded. In the density sensor 37, the transfer drum 3 is covered with a cover 38, and the cover 38 is provided with openings 38a and 38b at positions facing the transfer drum 3 and the process cartridge 4.

Further, the density sensor 37 is rotatably mounted around a shaft 37a and is rotated by a solenoid 39. That is, when the solenoid 39 is turned on, the density sensor 37 opens the opening 38a as shown in FIG.
17B, when the solenoid 39 is turned off, the density sensor 37 is attached to the process cartridge 4 via the opening 38b by a spring or the like (not shown) as shown in FIG. 17B. Opposite 40.

In the above structure, before the image forming operation, the solenoid 39 is turned off so that the density sensor 37 faces the color label 40 and the density of the color label 40 is detected. Then, the sensitivity level of the photosensitive drum 4a in the process cartridge 4 is determined by the density based on the information stored in advance. Next, when image formation is started, the solenoid 39 is turned on to make the density sensor 37 face the transfer drum 3, and the density of the transferred image of the recording material 2 wound around the drum 3 is detected. Image formation is performed so that the densities of the respective colors are the same.

As described above, the single density sensor 37 detects the sensitivity level of the photosensitive drum 4a and the transferred image density, thereby reducing the number of sensors and reducing the cost.

[Second Embodiment] In the first embodiment described above, the leaf spring 13 is provided as an elastic member on the inner surface of the cartridge cover 4e.
Is provided, and the process cartridge 4 is
Although an example in which the developing means 4c is biased to the photosensitive drum 4a has been shown, another embodiment related thereto will be described as a second embodiment. As shown in FIG. 18, the cartridge cover 4
Elastic vibration absorbing material such as urethane foam as an elastic member on the hand surface of e
41 may be provided, and the elastic vibration absorbing material 41 presses the container 4c1 of the developing means 4c toward the photosensitive drum 4a when the cartridge cover 4e is mounted as shown in FIG.

With this structure, when the developing means 4c is driven during image formation, the vibration of the developing means 4c is absorbed, and the soundproof effect is exerted to obtain a high quality image.

As shown in FIGS. 20 and 21, by providing both the leaf spring 13 and the elastic vibration absorber 41 on the inner surface of the cartridge cover 4e, the developing means 4c is biased by the leaf spring 13.
The elastic vibration absorber 41 may be made of a material optimal for absorbing vibration and soundproofing.

Further, as shown in FIGS. 22 and 23, guide holes 42 of the developing means 4c are provided on both side walls of the cartridge cover 4e so as to extend in the direction for urging the developing means 4c toward the photosensitive drum 4a. The guide shafts 43 provided on both sides of are fitted into the guide holes 42. Further, a spring 44 provided with the tail portion of the developing means 4c on the inner surface of the cartridge cover 4e.
Is urged toward the photosensitive drum 4a. Even in this case, when the cartridge cover 4e is mounted, the developing means 4c can be biased and positioned in the direction of the photosensitive drum 4a.

[Third Embodiment] In the first embodiment described above, an example is shown in which the upper waste toner container 4d2 is replaced when the waste toner is stored in the container of the cleaning means 4d to some extent. Another embodiment related to the present invention will be described as a third embodiment.

First, when the upper waste toner container 4d2 is full of waste toner, a means for detecting this may be provided. For example, as shown in FIG. 24, a loosened sheet 45 is attached to the upper surface of the upper waste toner container 4d2, and the toner container lid 46 is provided with a vertically slidable detection member 47. In this way, when the waste toner is stored in the upper waste toner container 4d2 by driving the feed roller 4d4, the sheet 45 swells and pushes the detection member 47 upward as shown in FIG. By detecting this with an optical sensor (not shown) or the like, it is possible to inform the upper waste toner container 4d2 that the waste toner is full. The sheet 45 may be stretchable.

In the above embodiment, the cleaning means 4d
An example in which the toner container lid 46 is provided on the upper waste toner container 4d2 is shown, but as shown in FIGS.
The upper surface of d2 may also be used as the toner container lid.

[Fourth Embodiment] In the first embodiment described above, the process cartridge 4 and the black developing unit 5 are maintained in a substantially horizontal posture even when the upper opening / closing cover 12 is opened / closed. However, another embodiment related to this will be described as a fourth embodiment.

28 (a) and 28 (b) show a holding structure of the process cartridge 4. A cartridge base 49 rotatable around a fulcrum 48 is attached to the process cartridge holding frame 14, and the process cartridge 4 is attached to the base 49. The process cartridge 4 is loaded in the loaded state. The fulcrum 48 is provided on the cartridge base 49 and a substantially vertical line of the center of gravity when the process cartridge 4 is loaded on the base 49.

With this structure, when the upper opening / closing cover 12 and the holding frame 14 are integrally rotated with the process cartridge 4 loaded, the opening / closing cover 12 is opened.
As shown in FIG. 28B, the cartridge base 49 rotates about the fulcrum 48 due to its own weight, and the process cartridge 4 maintains the substantially same posture as that in FIG. 28A in which the opening / closing cover 12 is closed. As a result, it is possible to prevent the toner in the process cartridge 4 from being clogged even when the opening / closing cover 12 is opened.

In the case of the above construction, the attitude of the cartridge 4 when the opening / closing cover 12 is opened changes to some extent depending on the toner consumption state in the process cartridge 4. It does not lean to the point of being clogged.

28 (a) and 28 (b), the holding structure of the process cartridge 4 has been described.
The holding structure may be similar.

Still another embodiment is shown in FIGS. 29 (a) and 29 (b). In this configuration, the process cartridge 4 is the photosensitive drum 4
The rotating shaft 4a3 of a is held by the hook mechanism 16. Protrusions 50 are formed at both ends of the rear portion of the cartridge 4, and the process cartridge holding frame 14 has the protrusions 50 at the lower end.
Is provided with a guide hook 51 having a hook portion 51a for locking.

When the holding frame 14 is opened together with the upper opening / closing cover 12, the protrusion 50 causes the hook portion 51 of the guide hook 51.
Until the process cartridge 4 is locked to
Rotate around a3 (that is, maintain the same state as when the opening / closing cover 12 is closed). Then, as shown in FIG. 29 (b),
When the protrusion 50 is engaged with the hook 51a, the process cartridge 4 is lifted upward together with the holding frame 14. In this case, the rear portion of the cartridge 4 is in a slightly lowered posture during the opening operation, but is finally in a substantially horizontal posture.

A hook 52 is provided at the lower end of the process cartridge 4, and the hook is provided on the black developing unit 5.
A protrusion 53 that locks to 52 is provided. Therefore, by locking the protrusion 53 with the hook 52, the black developing unit 5 can be loaded below the process cartridge 4, and the process cartridge 4 and the black developing unit 5 can be opened by the opening operation of the upper opening cover 12. Can be lifted together.

Even with the above-mentioned structure, when the opening / closing cover 12 is opened, the process cartridge 4 and the black developing unit 5 maintain substantially the same horizontal posture as when the opening / closing cover 12 is closed. It moves accurately from the developing container to the photosensitive drum 4a without being clogged in the section.

It should be noted that the above-mentioned structure is not always used for the black developing unit 5.
It is not necessary to limit to the image forming apparatus in which the toner is loaded, and it is needless to say that the invention can be suitably applied to an apparatus in which only the process cartridge 4 is loaded or an apparatus in which a monochromatic cartridge containing a black toner is loaded. is there.

[Fifth Embodiment] Further, in the above-described first embodiment, when the upper opening / closing cover 12 is closed, the process cartridge 4 and the black developing unit 5 are biased in the thrust direction and positioned. Although shown, another embodiment related thereto will be described as a fifth embodiment.

In the structure shown in FIGS. 30A and 30B, the process cartridge 4 has a positioning member for the black developing unit 5.
54 are provided. Then close the upper cover 12,
The plate springs 55a, 55b, 55c provided on the cover 12 position the positioning member 54 of the process cartridge 4 against the support member 56, and the black developing unit 5 is positioned by the positioning member.
Positioned in contact with 56.

Further, the bias positioning structure of the process cartridge 4 and the black developing unit 5 in the thrust direction is shown in FIG.
It may be configured as shown in (a) and (b).

In this structure, first, the black developing unit 5 is loaded on the supporting member 57 of the apparatus main body 9, and then the process cartridge 4 is loaded from the direction of the arrow in FIG. Fig. 31
As shown in (a), the side surface of the process cartridge 4 is biased in the thrust direction by the spring 58 provided on one side surface of the support member 57, and is pressed and positioned on the other side surface of the support member 57. When the process cartridge 4 is further pushed down, as shown in FIG. 31B, the black developing unit 5 is pressed by the spring 59 provided in the process cartridge 4 and pressed by the positioning member 60 of the process cartridge 4 to be positioned. It is a thing.

Further, as shown in FIGS. 32 (a) and 32 (b), a spring 61 is provided on the side surface of the black developing unit 5 so that the member 62 of the process cartridge 4 becomes the spring 61 when the process cartridge 4 is connected. The black developing unit 5 may be positioned by abutting and pressing the black developing unit 5 against the side wall of the supporting member 63.

Further, the thrust direction positioning structure can be applied to an image forming apparatus in which only the process cartridge 4 is loaded or an image forming apparatus in which a cartridge for developing a single color is loaded.

[Sixth Embodiment] Next, in the above-described first embodiment, an example in which the transfer drum 3 is freely rotated at the time of jam handling is shown, but another embodiment related thereto is the sixth embodiment.
This will be described as an example.

In the configuration shown in FIG. 33, the viscous gear 23 is provided on the upper opening / closing cover 12, the viscous gear 23 is separated from the driven gear 3h of the transfer drum 3 when the cover 12 is opened, and the viscous gear 23 is closed when the cover 12 is closed. Meshes with the driven gear 3h. By doing so, the solenoid as in the first embodiment described above is not required, and the number of parts can be reduced.

Further, as shown in FIG. 34, the viscous gear 23 may be attached to an arm 64 rotatable about a shaft 64a of the apparatus body 9, and a tension spring 65 may be attached to one end of the arm 64. .. In this case, when the upper opening / closing cover 12 is opened, the arm 64 is rotated in the counterclockwise direction by the spring 65, the viscous gear 23 is separated from the driven gear 3h of the transfer drum 3, and when the upper opening / closing cover 12 is closed, it is black. The arm 64 is pushed down by the developing unit 5, the arm 64 rotates clockwise, and the viscous gear 23 meshes with the driven gear 3h.

Further, the viscous gear 23 is disengaged from the driven gear 3h of the transfer drum when the upper opening / closing cover 12 is opened, so that the transfer drum 3 is freely rotated during the jam processing. It is needless to say that the present invention can be applied not only to an apparatus that loads the cartridge 4 and the black developing unit 5 to form a color image, but also to an image forming apparatus that loads only the process cartridge 4.

[Seventh Embodiment] Next, in the above-described first embodiment, the feeding force and the feeding load of the feeding means 1 are removed after the front end of the recording material 2 is gripped by the transfer drum 3. Although an example of doing so has been shown, another example related thereto will be described as a seventh example.

FIG. 35 shows the structure of the feeding means 1 according to another embodiment. This device is different from the above-mentioned first embodiment in that the sheet sensor 28 includes the feeding roller 1c1 and the registration roller. It is provided between the pair of rollers 66a and 66b, and the registration roller 66b is a half-moon roller. Then, the driving force of the feeding motor 33 is transmitted to the pickup roller 1b via the first electromagnetic clutch 32, and is transmitted to the registration roller 66b via the second electromagnetic clutch 67. Further, the driving force of the feeding motor 33 is transmitted to the feed roller 1c1 via the gear train. The feeding means 1 is drive-controlled by the procedure shown in the flowchart of FIG.

That is, in steps S21 to S23 of FIG. 36, the feed motor 33 starts to drive, and the first electromagnetic clutch 32 is turned on for a fixed time (T ₀ seconds from the start of feed motor drive).
As a result, the pickup roller 1b makes one rotation to separate and feed one recording material 2 in the cassette 1a. After the pickup roller 1b makes one rotation,
The chord portion of the recording medium 2 faces the recording material 2, and the pickup roller 1b is separated from the recording material 2. The recording material 2 picked up from the cassette 1a as described above is fed by the feed roller 1c1 and the retard roller 1c2.

When the leading edge of the recording material 2 is fed to the position of the sheet sensor 28, the recording material 2 moves to the sensor lever 28a.
To press, the sensor 28 turns on. When the sheet sensor 28 is turned on in step S24, the process proceeds to step S25, and the driving is stopped T ₁ seconds after the sensor 28 is turned on. At this time, the front end of the recording material 2 has a pair of registration rollers 66.
It has reached the positions of a and 66b.

Next, when the transfer drum sensor 29 is turned on in step S26, the process proceeds to steps S27 and S28, and the second electromagnetic clutch 67 is turned on T ₂ seconds after the drum sensor 29 is turned on, and at the same time the feeding motor 33 is driven. Then, the recording material 2 is fed by the pair of registration rollers 66a and 66b. Thereby, the gripper 3f of the transfer drum 3 rotating with the tip of the recording material 2
And Rendezvous, and the tip of the recording material is gripped by the gripper 3f.

Next, in steps S29 and S30, the step S
Solenoid 31a after T ₃ seconds from the start of feeding motor of 28
Is turned on to separate the retard roller 1c2 from the feed roller 1c1, and the second electromagnetic clutch 67 is turned off after T ₄ seconds from the start of driving the feeding motor. At this time, the feed roller 66b stops after rotating once, and the half-moon roller 66b
The recording material 2 has a string portion facing the feed roller 66a.
It will be separated from. Therefore, after the recording material 2 is gripped by the transfer drum 3, the feeding unit 1 is separated from the recording material 2, and the feeding force and the feeding load are removed.

Then, the recording material 2 is wound around the surface of the drum 3 as the transfer drum 3 rotates, and when the trailing edge of the recording material 2 passes the sheet sensor 28, that is, when the sheet sensor 28 is turned off in step S31, At S32 and S33, the driving of the feeding motor 33 is stopped and the solenoid 31a is turned off to bring the retard roller 1c2 into pressure contact with the feed roller 1c1.

Even in the above-described manner, it is possible to prevent the recording material 2 held by the transfer drum 3 from being pulled by the feeding means 1, and it is possible to prevent jamming and image color misregistration.

[Eighth Embodiment] In addition, in the above-described first and seventh embodiments, the recording material 2 held by the transfer drum 3 is used.
Although the example in which the conveying load is removed so that the feeding means 1 does not pull the feeding means 1 is shown, by changing the drive speed of the feeding motor 33, the recording material 2 has an appropriate slack and the transfer drum It may be delivered to the third party.

The feeding control procedure therefor may be as shown in the flow chart of FIG. 37, for example. In this case, in the image forming apparatus shown in the first embodiment, the sensor lever 28a is pushed while the recording material 2 is in a state where the recording material 2 is taut at the sensor position and is loose to some extent. The one that turns on and turns off when it is loosened further is used. Further, the solenoids 31a and 31b are both turned off, and the electromagnetic clutch 32 is turned on to drive the feeding motor 33. Further, the recording material 2 when the feeding motor 33 is driven at a normal speed
The feeding speed is set to be higher than the peripheral speed of rotation of the transfer drum 3.

Under the above setting, the feeding motor 33 is driven to feed the recording material 2, the tip of the recording material 2 is gripped by the gripper 3f of the transfer drum 3, and the recording material 2 is fed. When the recording medium 2 is spread over both the means 1 and the transfer drum 3, the recording material 2 is gradually loosened because the feeding speed of the feeding means 1 is high.

Therefore, the slack is controlled by the feeding control procedure shown in FIG. That is, in step S41, the feeding motor 33 is driven at a high speed to feed the recording material 2. First, the recording material 2 between the pair of registration rollers 1e1 and 1e2 and the transfer drum 3
Has a small slack, but the slack gradually increases during high speed feeding. When the slack exceeds a certain level, the sheet sensor 28 turns off. Therefore, when the sheet sensor 28 is turned off in step S42, the process proceeds to step S43, and the driving speed of the feeding motor 33 is switched to low speed feeding which is slower than the high speed. As a result, the slack is gradually reduced. When the slack becomes less than a certain value, the sheet sensor 28 is turned on. Therefore, when the sensor 28 is turned on in step S44, the process proceeds to step S45, and the feeding motor 33 is switched to high speed driving again.

Then, in step S46, it is determined whether or not the trailing edge of the recording material 2 has passed the registration rollers 1e1 and 1e2 by counting the number of drive pulses of the feeding motor 33 or by a separately provided sheet sensor or the like. If it has not passed, the process returns to step S42.

The feeding speed of the recording material 2 is set to be slightly higher than the peripheral speed of rotation of the transfer drum 3 even when the feeding motor 33 is driven at a low speed.

When the feeding control is performed as described above, the recording material 2 is always fed between the registration roller pairs 1e1 and 1e2 and the transfer drum 3 with an appropriate slack.
Does not pull the recording material 2 and does not jam it.

FIG. 38 shows an embodiment in which the sheet sensor 28 of the image forming apparatus according to the first embodiment is arranged above the guide plate 1d. In this case, when the slack of the recording material 2 becomes a certain value or more, the sensor lever 28a is pressed to switch from off to on.

The procedure for feeding the recording material 2 in the case of the above configuration is shown in the flow chart of FIG. In this case, as shown in steps S51 to S56, contrary to the procedure shown in FIG. 37, the sheet sensor 28 is fed at a low speed and when it is turned off, it is fed at a high speed.

Further, using the image forming apparatus according to the first embodiment, the recording material 2 is recorded according to the procedure of the flowchart shown in FIG.
May be sent.

In this feeding procedure, at the start of feeding, the feeding speed by the feeding motor 33 is made high, and after the tip of the recording material 2 is gripped by the gripper 3f of the transfer drum 3,
As shown in steps S61 and S62, high-speed feeding is performed for a certain period of time, and then low-speed feeding is switched. In this case, the recording material 2 is loosened at the time of switching to the low speed feeding, and the sheet sensor 28 is turned off.

The slack is gradually reduced by the low speed feeding. After that, as shown in steps S63 to S67, when the sheet sensor 28 is turned on, it is switched to high speed feeding, and when it is turned off, it is switched to low speed feeding.

As described above, even if the feeding speed of the recording material 2 is changed so that the recording material 2 is always fed to the transfer drum 3 with an appropriate slack, the recording material 2 is conveyed by the transfer drum 3. Since the feeding means 1 does not pull the recording material 2, it is possible to form an image without image misalignment.

By controlling as described above, the recording material 2 can be accurately fed even if the outer diameter of the transfer drum 3 varies.

[Ninth Embodiment] Next, in the above-described first embodiment, the density sensor 37 is rotated to detect the color level of the color label 40 and the density of the image transferred to the recording material 2. However, another embodiment relating to this will be described as a ninth embodiment.

If the toner or the like adheres to the surface of the density sensor 37 and stains it, accurate detection cannot be performed. Therefore, as shown in FIGS. 41 (a) and 41 (b), a cleaning member 66 is provided in the cover 38, and the cleaning member 66 is provided every time the sensor 37 performs a rotating operation.
66 may clean the surface of the sensor 37.

In the first embodiment described above, the density sensor 37
The image density transferred to the recording material 2 is detected by the method described above. For example, by attaching the density sensor 37 to the position shown in FIGS. 42 (a) and 42 (b), the image formed on the photosensitive drum 4a can be detected. The density may be detected.

In FIG. 42 (a), the color label 40 attached to the cartridge cover 4e is detected,
When detecting the image density of the photosensitive drum 4a, FIG.
The concentration sensor 37 is rotated as shown in FIG.
37 is opposed to the photosensitive drum 4a. With this configuration, the color density sensor 37 can detect the color label 40 and the density of the image formed on the photosensitive drum 4a.

In the first embodiment described above, the density sensor 37
Although the example in which the solenoid 39 is rotated by the solenoid 39 is shown, the density sensor 37 may be rotated by using the gear 3h attached to the shaft of the transfer drum 3 as shown in FIG.

The structure of FIG. 43 has a structure in which the shaft 37a of the density sensor 37 is geared.
67 is attached, and this gear 67 is configured to be connected to the gear 3h via an electromagnetic clutch 68. This concentration sensor
37 is usually a color label not shown as shown in FIG.
Opposite 40. When detecting the transfer image density of the recording material 2 wound around the transfer drum 3, the gear 3h is rotating because the transfer drum 3 is rotating.
Therefore, when the electromagnetic clutch 68 is turned on, its rotational force is changed to the gear.
This is transmitted to the sensor 67, and the density sensor 37 rotates as shown in FIG. 44B to face the recording material 2 on the transfer drum 3 to detect the image density.

Therefore, even with the above configuration, the density sensor 37 can detect the color label 40 and the transferred image density of the recording material 2.

The configuration in which the color label detection and the image density detection are performed by one density sensor 37 as described above can be applied to an image forming apparatus in which the process cartridge 4 or the black developing unit 5 is not mounted. It is natural.

[Other Embodiments] In the above-described first embodiment, an example in which a full-color image is formed with four colors of yellow, magenta, cyan, and black has been shown, but the present invention is not limited to this, and three colors of yellow, magenta, and cyan are used. Of course, a full-color image may be formed with colors.

Furthermore, the present invention is not limited to the case of forming a full-color image as described above, but is also applicable to the case of forming a multi-color image such as forming a single-color image of a plurality of colors (for example, a two-color image or a three-color image) It is preferably used. Therefore, in the above-described first embodiment, the example in which the black toner is stored in the black developing unit 5 has been shown, but the color toner other than black (for example, red toner) may be stored in the unit 5. Further, the process cartridge 4 may be provided with one developing means to store only one color toner.

As the developing method, various known developing methods such as a two-component magnetic brush developing method, a cascade developing method, a touchdown developing method and a cloud developing method can be used.

As for the structure of the charging means, the so-called contact charging method was used in the above-described first embodiment, but a tungsten wire which has been conventionally used as another structure is provided with a metal shield such as aluminum around three sides, It is of course possible to use a configuration in which positive or negative ions generated by applying a high voltage to the tungsten wire are moved to the surface of the photosensitive drum 4a and the surface of the drum 4a is uniformly charged. ..

As a method for cleaning the toner remaining on the photosensitive drum 4a, the cleaning means may be constituted by using a blade, a fur brush, a magnetic brush or the like.

Further, in the above-described first embodiment, when an image is formed on the recording material 2, yellow, magenta, cyan,
An example of using a so-called multiple transfer system in which each color toner of black is transferred to the recording material 2 has been described. However, as this transfer system, another system such as latent image formation of each color on the photosensitive drum 4a, A so-called multiple development batch transfer system may be adopted in which images are superimposed on the photosensitive drum 4a by repeating development and the superimposed toner images of respective colors are collectively transferred to the recording material 2. The latent images of each color are sequentially formed on the body belt so that they do not overlap with each other, and this is developed, and the developed toner is transferred as an image superimposed on the transfer belt, which is an intermediate transfer body, and then transferred collectively onto the recording material. It is also possible to adopt a transfer method.

Further, although the laser beam printer is illustrated as the image forming apparatus in the above-described first embodiment, the present invention is not limited to this, and can be naturally used in other image forming apparatus such as a copying machine. It is possible.

[0186]

Since the cartridge and the image forming apparatus according to the present invention are configured as described above, they have the following effects.

(1) Since the elastic member for pressing the developing means is provided on the inner surface of the cartridge cover, when the cartridge cover is mounted, the developing means is urged toward the image carrier by the elastic member. As a result, the image carrier and the developing device can be positioned by simply mounting the cartridge cover, and the assembling property of the cartridge is improved. Further, since the spring and the like are not exposed to the outside of the cartridge, the handleability is also improved.

If an elastic vibration absorbing material such as urethane foam is used as the elastic member, it is possible to prevent vibration and rattling of the developing means and to absorb sound. Therefore, by using the cartridge in the image forming apparatus, it is possible to obtain a high quality image.

(2) In the present invention, the waste developer container of the cleaning means is divided into the first container and the second container, and the second container is detachable from the first container. It is possible to process a large amount of waste developer without causing the change. Therefore, when the cleaning means and the image carrier and the developing means are integrated into a cartridge, the cartridge can be downsized, and the image forming apparatus in which the cartridge is loaded can also be downsized.

When the second container is replaceable as described above, especially in an apparatus configured to form an image by loading a developing unit separately from the cartridge having the image carrier and the cleaning means, for example, Even if the black developing unit for performing the black developing to be used is loaded separately from the image carrier and used by exchanging it, the waste developer can be treated without exchanging the cartridge, which is convenient.

(3) In the present invention, since the cartridge is biased and positioned in the thrust direction of the rotary shaft of the image carrier, the cartridge is not enlarged, and the attachment / detachment operability is not deteriorated. It can be loaded into the main body, and the drive system and the electrical system can be accurately connected to the cartridge.

If the cartridge is urged by the operation of the opening / closing cover, the operation for positioning the cartridge becomes unnecessary, and the attaching / detaching operability is further improved.

Further, in the structure in which the developing unit is loaded in addition to the cartridge, the cartridge and the developing unit are biased by the biasing means to perform the positioning in the thrust direction, so that the two can be connected more reliably. Can be done.

(4) In the present invention, the cartridge moves together with the opening / closing cover that can be opened / closed with respect to the main body of the apparatus. Even when the opening / closing cover is opened, the cartridge maintains substantially the same posture as when the opening / closing cover is closed. Therefore, the posture of the cartridge does not change significantly.

Therefore, the developer in the cartridge can be prevented from spilling due to the inclination of the cartridge, and the clogging of the developer can be prevented. Therefore, in the case of jam processing or the like, the opening / closing cover can be opened wide for processing, and the operability of jam processing or the like is improved.

(5) According to the present invention, by controlling the drive speed of the feeding means for feeding the recording material to the transfer rotator, it is possible to appropriately maintain the slack in feeding the recording material. .. For this reason, it is possible to prevent the feeding member from pulling the recording material conveyed by the transfer rotator, and it is possible to form an image without color misregistration.

Further, even if the distance between the feeding means and the approach of the transfer rotator is shortened to downsize the apparatus, the recording material can be properly conveyed by the transfer rotator. Further, the recording material can be stably fed even if the outer diameter of the transfer rotary member varies.

(6) Further, according to the present invention, after the recording material is conveyed by the transfer rotator, the recording material is conveyed by the transfer rotator by removing the feeding load by the feeding means. The recording medium can be prevented from being pulled by the feeding means, and an image without color misregistration can be formed.

(7) In the present invention, the gear for transmitting the rotational force to the transfer rotary member around which the recording material is wound can be meshed with and disengaged from the gear having a constant rotational load. The rotating force can be accurately transmitted to the transfer rotator, and the jam can be easily removed by manually rotating the transfer rotator during jam processing.

(8) In the present invention, the density detecting means is also used as the sensitivity level detecting means of the image carrier, whereby the number of parts of the detecting member can be reduced and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall schematic explanatory diagram of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a configuration of a process cartridge.

FIG. 3 is an external perspective view of a process cartridge.

FIG. 4 is an explanatory diagram of a positioning configuration of a developing sleeve with respect to a photosensitive drum.

FIG. 5 is an explanatory view of a state in which a cover of the process cartridge is removed.

FIG. 6 is an explanatory view showing a state in which a cover of the process cartridge is loaded.

FIG. 7 is an explanatory diagram of a configuration of cleaning means.

FIG. 8 is an explanatory view showing a state in which the second container is removed from the first container of the cleaning means.

FIG. 9 is a diagram illustrating a loading configuration of a process cartridge.

FIG. 10 is an explanatory view of the state of the process cartridge when the open / close cover is opened.

FIG. 11 is an explanatory diagram when a process cartridge and a black developing unit are replaced and a jam process is performed.

FIG. 12 is an explanatory diagram of thrust direction biasing means of the process cartridge and the black developing unit.

FIG. 13 is an explanatory diagram of a biasing configuration of the process cartridge and the black developing unit in the thrust direction when the upper opening / closing cover is closed.

FIG. 14 is an explanatory diagram of a configuration in which a driven gear and a viscous gear of a transfer drum are engaged and disengaged.

FIG. 15 is a block diagram of a feeding control configuration.

FIG. 16 is a flowchart of a feeding control procedure.

FIG. 17 is an operation explanatory diagram of the density detection sensor.

FIG. 18 is an explanatory view showing a state where the cartridge cover according to the second embodiment using an elastic vibration absorbing material as an elastic member provided on the inner surface of the cartridge cover is removed.

19 is an explanatory view of a state where the cartridge cover of FIG. 18 is attached.

FIG. 20 is an explanatory view showing a state where the cartridge cover of the embodiment using both the leaf spring and the elastic vibration absorbing material as the elastic member on the inner surface of the cartridge cover is removed.

21 is an explanatory view showing a state in which the cartridge cover of FIG. 20 is loaded.

FIG. 22 is an illustration showing a state where the cartridge cover of the embodiment in which the developing means is attached to the cartridge cover is removed.

FIG. 23 is an explanatory view showing a state where the cartridge cover of FIG. 22 is loaded.

FIG. 24 is an explanatory diagram of an embodiment in which a member for detecting that the waste toner is full is provided in the waste toner container of the cleaning unit.

FIG. 25 is an explanatory diagram showing a state where the waste toner container shown in FIG. 24 is full of waste toner.

FIG. 26 is an explanatory diagram of an embodiment in which the upper waste toner container also serves as a container lid.

27 is an explanatory view of a state where the upper waste toner container of FIG. 26 is removed.

FIG. 28 is an explanatory view of another embodiment in which the process cartridge is maintained in substantially the same posture even when the upper opening / closing cover is opened / closed.

FIG. 29 is an explanatory view of another embodiment in which the process cartridge is maintained in substantially the same posture even when the upper opening / closing cover is opened / closed.

FIG. 30 is an explanatory diagram of another embodiment for urging and positioning the process cartridge and the black developing unit in the thrust direction.

FIG. 31 is an explanatory diagram of another embodiment for urging and positioning the process cartridge and the black developing unit in the thrust direction.

FIG. 32 is an explanatory diagram of another embodiment for urging and positioning the process cartridge and the black developing unit in the thrust direction.

FIG. 33 is an explanatory diagram of another embodiment for releasing the meshing between the viscous gear and the gear of the transfer drum.

FIG. 34 is an explanatory diagram of another embodiment for releasing the meshing between the viscous gear and the gear of the transfer drum.

FIG. 35 is an explanatory diagram of an example in which the registration roller is a half-moon roller.

36 is a flowchart showing a carrying procedure for removing the load of the feeding means by using the feeding means of FIG. 35.

FIG. 37 is a flowchart of a feeding procedure for feeding the recording material while appropriately slackening the recording material between the registration roller and the transfer drum.

FIG. 38 is an explanatory diagram of a feeding configuration in which a sheet sensor is turned on when the slack of a recording material increases.

FIG. 39 is a flowchart of a procedure for controlling the slack of the recording material by driving the feeding unit of FIG. 38.

FIG. 40 is a flowchart of a procedure for feeding a recording material at a high speed for a fixed time after the feeding is started.

FIG. 41 is an explanatory diagram of an example in which the cleaning member cleans the sensor by rotating the density sensor.

FIG. 42 is an illustration of an embodiment in which a color sensor detects a color label and the density of an image formed on a photosensitive drum is detected.

FIG. 43 is an explanatory diagram of an example in which the density sensor is rotated by using the rotational force of the transfer drum.

44 is an explanatory view of a state where the density sensor of FIG. 43 is rotated.

FIG. 45 is an explanatory diagram of a conventional example showing a biasing positioning configuration of the sleeve of the developing device and the image carrier.

FIG. 46 is an explanatory diagram of a conventional example showing a state of the cartridge when the opening / closing cover loaded with the cartridge is opened / closed.

FIG. 47 is an explanatory diagram of a conventional example showing a drive transmission configuration for a transfer drum and a meshing state of a viscous gear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Feeding means 1b ... Pickup roller 1c1 ... Feed roller 1c2 ... Retard roller 1e1, 1e2 ... Registration roller pair 2 ... Recording material 3 ... Transfer drum 3f ... Gripper 4 ... Process cartridge 4a ... Photosensitive drum 4a3 ... Rotating shaft 4b ... Charging unit 4c ... Developing unit 4d ... Cleaning unit 4d1 ... Lower waste toner container 4d2 ... Upper waste toner container 4e ... Cartridge cover 4f ... Exposure unit 5 ... Black developing unit 6 ... Fixing unit 7 ... Ejecting roller 8 ... Ejecting unit 9 ... Device Main body 10 ... Scanner section 12 ... Upper opening / closing cover 13 ... Leaf spring 14 ... Process cartridge holding frame 15 ... Black developing unit holding frame 16 ... Hook mechanism 22 ... Biasing means 23 ... Viscous gear 25 ... Solenoid 27 ... Control section 27a ... CPU 28 ... Sheet sensor 28a ... Sensor lever 29 ... Transfer drum sensor 31a ... First solenoid 31b ... Second Solenoids 32 ... electromagnetic clutch 33 ... feed motor 37 ... concentration sensor 40 ... color label

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G03G 15/08 7810-2H 21/00 113 H04N 1/00 D 7046-5C 1/29 F 9186- 5C (72) Inventor Ryo Ito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (58)

[Claims] 1. An image carrier, a developing unit that is positioned with a constant gap with respect to the image carrier, and develops an image formed on the image carrier, the image carrier, and A cartridge cover that is mounted so as to cover the developing means, and an elastic member is provided on the inner surface of the cartridge cover. By mounting the cartridge cover, the developing means is urged toward the image carrier through the elastic member. A cartridge characterized by being configured to. 2. The cartridge according to claim 1, wherein, in addition to the image carrier and the developing means, a charging means and a cleaning means are covered with the cartridge cover to be integrated. 3. The cartridge according to claim 1, wherein said cartridge has a developing means for developing each color of yellow, magenta and cyan as a developing means. 4. An image comprising: a loading unit for loading the cartridge according to claim 1; and a transport unit for transporting a recording material. Forming equipment. 5. A first loading means for loading the cartridge according to any one of claims 1 to 3, and a second loading means for loading a developing unit having a developing means, An image forming apparatus comprising: a conveying unit configured to convey a recording material. 6. The image forming apparatus according to claim 5, wherein the developing unit has a developing unit for performing black development. 7. An image carrier, a developing unit for developing the image formed on the image carrier, and a cleaning unit for cleaning the developer remaining on the image carrier, The cleaning means has a first container for containing the cleaned developer and a second container for containing the developer irreversibly sent from the first container, and the second container is the first container. A cartridge characterized by being configured to be attachable to and detachable from a container. 8. The cartridge has a charging unit in addition to the image carrier, a developing unit and a cleaning unit, and these are integrally formed into a cartridge.
The described cartridge. 9. The image forming apparatus according to claim 7, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 10. An image carrier, a developing unit for developing an image formed on the image carrier, and a cleaning unit for cleaning the developer remaining on the image carrier, The cleaning means has a first container for containing the cleaned developer and a second container for containing the developer irreversibly sent from the first container, and the second container is the first container. An image forming apparatus comprising: a loading unit for loading a cartridge that is configured to be detachable from and a transporting unit for transporting a recording material. 11. An image carrier, a developing unit for developing an image formed on the image carrier, and a cleaning unit for cleaning the developer remaining on the image carrier, The cleaning means has a first container for containing the cleaned developer and a second container for containing the developer irreversibly sent from the first container, and the second container is the first container. A first loading means for loading a cartridge configured to be detachable with respect to the second loading means, a second loading means for loading a developing unit having a developing means, and a feeding means for feeding the recording material. An image forming apparatus characterized by the above. 12. The image forming apparatus according to claim 11, wherein the developing unit has a developing unit for performing black development. 13. A loading unit for loading a cartridge including an image carrier and a developing unit for developing an image formed on the image carrier, and a cartridge loaded in the loading unit. And an urging unit for urging and positioning the image carrier in a direction parallel to the rotation axis direction of the image carrier. 14. A first loading unit for loading a cartridge including an image carrier and a developing unit for developing an image formed on the image carrier, and a developing unit including a developing unit. A second loading unit for loading, a cartridge loaded in the first loading unit, and a developing unit loaded in the second loading unit are urged in a direction parallel to the rotation axis direction of the image carrier. An image forming apparatus comprising: an urging unit for positioning. 15. The image forming apparatus according to claim 13, wherein the biasing unit is configured to bias the cartridge when the opening / closing cover that can be opened / closed with respect to the apparatus main body is closed. 16. The cartridge according to claim 13 or 14, wherein at least an electrophotographic photosensitive member as an image bearing member and a developing means are integrally formed into a cartridge, which is attachable to and detachable from the apparatus main body. The image forming apparatus described. 17. The cartridge integrally comprises an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit acting on the electrophotographic photosensitive member. 13. The device according to claim 13, which is detachable from the device body.
14. The image forming apparatus described in 14. 18. The cartridge comprises an electrophotographic photosensitive member as an image carrier, a charging means, a developing means, and a cleaning means, which are integrally formed into a cartridge and can be attached to and detached from the apparatus main body. Claim 13 or Claim 14
The image forming apparatus described. 19. The image forming apparatus according to claim 14, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 20. The image forming apparatus according to claim 14, wherein the developing unit has a developing unit for performing black development. 21. An image carrier, a developing means for developing an image formed on the image carrier, a transfer rotator for winding and rotating a recording material around a peripheral surface, and the transfer rotator. A first gear for integrally transmitting a rotational force to the transfer rotary member, and a second gear having a constant rotational load with respect to rotation, wherein the second gear is the first gear. An image forming apparatus characterized in that it is configured to engage and disengage with a gear. 22. A loading unit for loading a cartridge equipped with an image carrier and a developing unit for developing an image formed on the image carrier, and a recording material wound around a peripheral surface and rotated. And a second gear having a constant rotational load with respect to the transfer rotary body, wherein the second gear meshes with and disengages from the first gear. An image forming apparatus characterized by. 23. A first loading unit for loading a cartridge having an image carrier and a developing unit for developing an image formed on the image carrier; and a developing unit having a developing unit. Second loading means for loading, a transfer rotator for winding and rotating a recording material around a peripheral surface, and a transfer rotator integrally provided on the transfer rotator for transmitting a rotational force to the transfer rotator. An image having a first gear and a second gear having a constant rotational load with respect to rotation, wherein the second gear is configured to mesh with and disengage from the first gear. Forming equipment. 24. The second gear is a viscous gear.
The image forming apparatus according to any one of claims 21 to 23. 25. The structure in which the engagement of the second gear and the first gear is released by opening the opening / closing cover of the apparatus main body, and the engagement of the second gear and the first gear by closing the opening / closing cover. 24. The image forming apparatus according to claim 23. 26. The cartridge integrally includes an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit acting on the electrophotographic photosensitive member, Claim 22 or claim that is detachable from the device body
23. The image forming apparatus according to item 23. 27. The cartridge comprises an electrophotographic photosensitive member as an image carrier, a charging unit, a developing unit, and a cleaning unit, which are integrally formed as a cartridge and can be attached to and detached from the apparatus main body. Claim 22 or Claim 23
The image forming apparatus described. 28. The image forming apparatus according to claim 22, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 29. The image forming apparatus according to claim 23, wherein the developing unit has a developing unit for performing black development. 30. An image carrier, a developing means for developing an image formed on the image carrier, a transfer rotator for winding and rotating a recording material around a peripheral surface, and the transfer rotator. A feeding means for feeding the recording material to the recording material, and a feeding force and a feeding load to the recording material by the feeding means when the recording material is held and rotated by the transfer rotating body. An image forming apparatus, comprising: a control unit for controlling so as to cancel. 31. A loading means for loading a cartridge equipped with an image carrier and a developing means for developing an image formed on the image carrier, and a recording material wound around a peripheral surface and rotated. A transfer rotator for feeding, a feeding unit for feeding a recording material to the transfer rotator, and the feeding unit when the recording material is held and rotated by the transfer rotator. An image forming apparatus comprising: a control unit configured to control a feeding force and a feeding load to a recording material to be released. 32. A first loading unit for loading a cartridge having an image carrier and a developing unit for developing an image formed on the image carrier, and a developing unit having a developing unit. Second loading means for loading, a transfer rotator for winding and rotating a recording material around a peripheral surface, a feeding means for feeding the recording material to the transfer rotator, and the recording material Control means for controlling so as to release the feeding force and feeding load to the recording material by the feeding means when the material is held and rotated by the transfer rotator. Image forming apparatus. 33. The cartridge integrally comprises an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit acting on the electrophotographic photosensitive member. Claim 31 or claim that is detachable from the device body
32. The image forming apparatus according to item 32. 34. The cartridge comprises an electrophotographic photosensitive member as an image carrier, a charging unit, a developing unit, and a cleaning unit, which are integrally formed as a cartridge and can be attached to and detached from the apparatus main body. Claim 31 or Claim 32
The image forming apparatus described. 35. The image forming apparatus according to claim 31, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 36. The image forming apparatus according to claim 32, wherein the developing unit has a developing unit for performing black development. 37. An image carrier, a developing means for developing an image formed on the image carrier, a transfer rotator for winding and rotating a recording material around a peripheral surface, and the transfer rotator. A feeding unit for feeding a recording material to the recording medium, the feeding unit, and a position where the transfer rotating body receives the recording medium, for detecting looseness of the recording medium. An image forming apparatus comprising: a slack detecting means; and a control means for changing a feeding speed of the recording material by the feeding means according to a signal from the slack detecting means. 38. A loading unit for loading a cartridge including an image carrier and a developing unit for developing an image formed on the image carrier, and a recording medium wound around a peripheral surface and rotated. And a feeding unit for feeding a recording material to the transfer rotating body, the feeding unit, and a position where the transfer rotating body receives the recording material. A slack detecting means for detecting slack of the recording material, and a control means for changing a feeding speed of the recording material by the feeding means in response to a signal from the slack detecting means. An image forming apparatus characterized by the above. 39. A first loading unit for loading a cartridge having an image carrier and a developing unit for developing an image formed on the image carrier, and a developing unit having a developing unit. Second loading means for loading, a transfer rotator for winding and rotating a recording material around a peripheral surface, a feeding means for feeding the recording material to the transfer rotator, and the feeding Means and a position where the transfer rotator receives the recording material, the slack detecting means for detecting slack of the recording material, and the feeding in response to a signal from the slack detecting means. An image forming apparatus comprising: a control unit configured to change a feeding speed of a recording material by the unit. 40. The cartridge integrally comprises an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit acting on the electrophotographic photosensitive member. Claim 38 or Claim that is detachable from the device body
39. The image forming apparatus according to item 39. 41. The cartridge comprises an electrophotographic photosensitive member as an image carrier, a charging unit, a developing unit, and a cleaning unit, which are integrally formed as a cartridge and can be attached to and detached from the apparatus main body. Claim 38 or Claim 39
The image forming apparatus described. 42. The image forming apparatus according to claim 38 or 39, wherein the cartridge has a developing means for developing each color of yellow, magenta, and cyan as a developing means. 43. The image forming apparatus according to claim 39, wherein the developing unit has a developing unit for performing black development. 44. An apparatus main body, an openable / closable cover that can be opened and closed by rotating with respect to the apparatus main body, an image carrier, and a developing unit for developing an image formed on the image carrier. Loading means for loading the cartridge, transporting means for transporting the recording material, moving the cartridge together with the opening / closing cover when the opening / closing cover is opened, and moving the cartridge when the opening / closing cover is opened. An image forming apparatus comprising: means for maintaining the attitude of the cartridge substantially the same as the attitude when the opening / closing cover is closed. 45. An apparatus main body, an opening / closing cover which can be opened and closed by rotating with respect to the apparatus main body, an image carrier, and a developing unit for developing an image formed on the image carrier. A first loading means for loading the cartridge, a second loading means for loading the developing unit having the developing means, a transporting means for transporting the recording material, and the opening / closing cover opened. And means for moving the cartridge and the developing unit together with the opening / closing cover and maintaining the posture of the cartridge and the developing unit when the opening / closing cover is opened to be substantially the same as the posture when the opening / closing cover is closed. An image forming apparatus characterized by the above. 46. The cartridge integrally comprises an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit acting on the electrophotographic photosensitive member, Claim 44 or Claim that is detachable from the device body
45. The image forming apparatus according to item 45. 47. The cartridge comprises an electrophotographic photosensitive member as an image bearing member, a charging unit, a developing unit, and a cleaning unit, which are integrally formed as a cartridge and can be attached to and detached from the apparatus main body. Claim 44 or Claim 45
The image forming apparatus described. 48. The image forming apparatus according to claim 44 or claim 45, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 49. The image forming apparatus according to claim 45, wherein the developing unit has a developing unit for performing black development. 50. An image carrier, a developing means for developing an image formed on the image carrier, a transfer rotator for winding and rotating a recording material around a peripheral surface, and the recording material. An image forming apparatus comprising: a density detecting unit for detecting the density of the image transferred to the image forming apparatus, wherein the density detecting unit reads the sensitivity level of the image carrier. 51. A loading means for loading a cartridge equipped with an image carrier and a developing means for developing an image formed on the image carrier, and a recording material wound around a peripheral surface and rotated. And a density detection unit for detecting the density of the image transferred to the recording material, and the density detection unit reads the sensitivity level of the image carrier. Image forming apparatus. 52. A first loading unit for loading a cartridge including an image carrier and a developing unit for developing an image formed on the image carrier, and a developing unit including a developing unit. It has a second loading means for loading, a transfer rotator for winding and rotating a recording material around the peripheral surface, and a density detecting means for detecting the density of the image transferred to the recording material. Then, the image forming apparatus is characterized in that the density detecting means reads the sensitivity information of the image carrier. 53. The image forming apparatus according to claim 51 or 52, wherein sensitivity information of an image carrier read by the density detecting means is provided in the cartridge. 54. A cleaning means for cleaning the density detecting means is provided, and the density detecting means moves from a sensitivity reading position of the image carrier to a position for detecting the density of an image transferred to a recording material. 53. The image forming apparatus according to claim 51 or 52, wherein the cleaning unit cleans the density detecting unit. 55. The cartridge integrally includes an electrophotographic photosensitive member as an image bearing member, a developing unit, and a charging unit or a cleaning unit as a process unit that acts on the electrophotographic photosensitive member. Claim 51 or Claim that is detachable from the device body
52. The image forming apparatus according to item 52. 56. The cartridge comprises an electrophotographic photosensitive member as an image carrier, a charging unit, a developing unit, and a cleaning unit for cleaning the developer remaining on the image carrier, which are integrally formed into a cartridge. 53. The image forming apparatus according to claim 51 or 52, which is removable from the main body. 57. The image forming apparatus according to claim 51, wherein the cartridge has a developing unit for developing each color of yellow, magenta, and cyan as a developing unit. 58. The image forming apparatus according to claim 52, wherein the developing unit has a developing unit for performing black development.