JP2002006608A - Developer replenishing container and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developer replenishing container which can enhance reliability of toner replenishment and can be realized miniaturization by developing furthermore the prior technology, and an image forming device provided with the same at a low cost. SOLUTION: In a typical configuration of the developer replenishing container and the image forming device, while rotating two drive transmission means in the same direction, a recessed part 51a being a positioning part is disposed between centers of rotation of the two drive transmission means in a stirring shaft 56 and a screw 58, and the interior angle made by straight lines tying the positioning part with the centers of rotation of the two drive transmission means is set so as to get 120 deg. to 180 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer supply container for supplying a developer in an electrophotographic image forming apparatus, and an image forming apparatus having the same.

[0002]

2. Description of the Related Art As an image forming apparatus for forming an image on a recording medium by using an electrophotographic image forming method, a copying machine, a printer (laser beam printer, LED printer, etc.), a facsimile machine, a word processor and the like are provided. Conventionally, a fine powder toner has been used as a developer in such an image forming apparatus. When the toner is consumed, toner is supplied to the developing device using a developer supply container (or a developer supply container).

Here, since the toner is an extremely fine powder, it is necessary to configure the toner so that the toner does not scatter during the toner replenishing operation. Therefore, a method has been known in which the developer supply container is set in the apparatus main body, and the developer supply container is discharged little by little from a small opening provided in the developer supply container to a supply port of the developing device. At this time, it is difficult for the toner to be spontaneously discharged by the action of gravity or the like, so some kind of toner conveying means is required.

In order to efficiently transport the toner in the developer supply container, it is desirable to provide a stirring means in the developer supply container in addition to the toner transport means. An example of such a developer supply container is disclosed in Japanese Patent Application Laid-Open No. H11-073000.

[0005] In such a method, the toner can be replenished without excess or shortage, and the amount of toner in the developing device can be kept constant. In particular, when a two-component developer is used, it is also effective to always maintain the mixing ratio of the carrier component and the toner component at a constant level.

[0006]

However, the rotational moment of the rotating body is applied to the positioning portion of the developer supply container depending on the arrangement of the driving transmission portion in the rotation direction of the developer supply container relative to the apparatus main body. Therefore, as described above, in the developer supply container having at least two rotating bodies of the conveying means and the stirring means, since there are two drive input portions (drive transmitting portions) of the rotating bodies, two rotational moments are combined and applied. Will be. When a large load is generated due to the rotational driving of the rotating body, the positioning portion is displaced, and the position of the discharge port of the developer supply container may be displaced from the position of the supply port on the apparatus body side.

Conventionally, in order to absorb such a displacement of the discharge port, for example, a structure has been adopted in which the supply port is made sufficiently large to cope with the displacement. However, this configuration requires an extra space, which hinders miniaturization of the device.

In order to provide an inexpensive and highly reliable developer supply container, it is important how to easily and accurately position the developer supply container in the apparatus main body. For example, it is possible to prevent toner from scattering around the openings by precisely matching the discharge port and the supply port. Further, by adjusting the drive transmission portion of the rotating member with high precision, for example, when the rotating member is a developer conveying unit, toner can be supplied with higher precision.

In view of the above-mentioned problems, the present invention is a further development of the prior art, which makes it possible to increase the reliability of toner replenishment and reduce the size of a developer replenishing container and an image forming apparatus provided with the same. It is intended to provide.

[0010]

In order to solve the above-mentioned problems, a typical configuration of a developer supply container and an image forming apparatus according to the present invention includes at least a positioning portion for attaching to a main assembly of the apparatus, and a developer. A developer accommodating section for accommodating, and an outlet for discharging the developer accommodated in the developer accommodating section;
In a developer supply container having a plurality of rotating members and two drive transmitting units for transmitting a driving force to the rotating members, and supplying a developer to a developing unit of the electrophotographic image forming apparatus, While rotating the drive transmission means in the same direction, arranging the positioning portion between the rotation centers of the two drive transmission means, and an angle formed by a straight line connecting the positioning portion and the rotation center of each drive transmission means Inner angle of 120 ° or more 1
It is characterized by being configured to be 80 ° or less.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a developer supply container and an image forming apparatus according to the present invention will be described with reference to the drawings. 1 is an external perspective view of the image forming apparatus according to the embodiment, FIG. 2 is an overall configuration diagram of the image forming apparatus according to the embodiment, FIG.
4 is a longitudinal sectional view of the developer supply container, FIG. 5 is an external perspective view of the developer supply container, FIG. 6 illustrates a state in which the developer supply container is mounted on a process cartridge, and FIG. 8 is a longitudinal sectional view of the developer supply container, FIG. 9 is an enlarged view of the vicinity of the discharge port, FIG. 10 is a longitudinal sectional view of the process cartridge, and FIGS. FIG. 6 is a diagram for explaining a combined load due to

In the present embodiment, the image forming apparatus will be described by taking a color electrophotographic image forming apparatus as an example. In the following description, the longitudinal direction refers to a direction in which the process cartridge 3 is mounted, and a direction crossing (substantially perpendicular to) the conveying direction of the recording medium P, and this direction is the axis of the photosensitive drum 4 serving as an image carrier. Same as the direction. The left and right are the left and right as viewed from the transport direction of the recording medium P. Further, the upper and lower sides mean the upper and lower sides in the mounted state of the process cartridge 3.

(Overall Configuration) First, the overall configuration of the image forming apparatus will be described with reference to FIG. The image forming apparatus 1 shown in FIG. 1 has four process cartridges 3 each having a drum-shaped electrophotographic photosensitive member (hereinafter, referred to as a photosensitive drum 4) as an image carrier, and respective colors corresponding to the upper portions of the process cartridges 3. Of laser exposure means 2 are arranged in parallel. Toner is supplied to the process cartridge 3 by a toner supply container 50 which is a developer supply container described later, and a toner image as a developer image is formed on the photosensitive drum 4. The formed toner image is transferred to the intermediate transfer belt 28.
Is transferred in a superimposed manner.

A sheet conveying means 35 for conveying the recording medium P is disposed below the image forming apparatus. After the toner images on the intermediate transfer belt 28 are collectively transferred, the toner images are fixed by a fixing device 43, and then the image forming apparatus is externally mounted. To be discharged. Here, the recording medium P is, for example, a sheet, an OHP sheet, a cloth, or the like. Note that the image forming apparatus in this embodiment is a cleanerless system, and the transfer residual toner remaining on the photosensitive drum 4 is taken into the developing unit 6, and a cleaner for collecting and storing the transfer residual toner is provided in the process cartridge 3. Is not placed.

In the present embodiment, the developer is a two-component developer in which a toner component and a carrier component are mixed.
The toner used is a negatively charged toner having an average particle diameter of 6 μm, and the magnetic carrier has a saturation magnetization of 205 emu / cm ^{3 and} an average particle diameter of 35 μm.
Was used. A mixture of a toner component and a carrier component at a weight ratio of 6:94 is used as a developer. Hereinafter, the configuration of each unit of the image forming apparatus will be sequentially described.

(Process Cartridge) In the process cartridges 3Y, 3M, 3C and 3K (yellow, magenta, cyan and black), charging means 5 and developing means 6 are provided around the photosensitive drum 4 as shown in FIG. They are arranged and integrated. And this process cartridge 3
Is easily replaced by the user with respect to the image forming apparatus main body (hereinafter simply referred to as the apparatus main body 1), and is replaced when the photosensitive drum 4 reaches the end of its life. For example, in the present embodiment, the number of rotations of the photosensitive drum 4 is counted, and when the count exceeds a predetermined count, it is notified that the life of the process cartridge 3 has expired.

The photosensitive drum 4 according to the present embodiment is a negatively charged organic photosensitive member, and has a normally used photosensitive layer on an aluminum drum base having a diameter of about 30 mm. Is provided. Then, it is driven to rotate at a predetermined process speed, about 117 mm / sec in this embodiment.
The charge injection layer uses a coating layer of a material in which, for example, SnO ₂ ultrafine particles are dispersed as conductive fine particles in a binder of an insulating resin.

A drum flange 4b is fixed to the rear end of the photosensitive drum 4 (see FIG. 10), and a non-drive flange 4d is fixed to the front end. The drum shaft 4a penetrates the center of the drum flange 4b and the non-drive flange 4d, and the drum shaft 4a, the drum flange 4b, and the non-drive flange 4d rotate integrally. That is, the photosensitive drum 4 is rotated around the drum shaft 4a. Drum shaft 4
The front side end of a is rotatably supported by a bearing 4e, and the bearing 4e is fixed to a bearing case 4c. The bearing case 4c is mounted on the frame 3 of the process cartridge 3.
a.

(Charging Means) The charging means according to this embodiment uses a contact charging method, and uses a magnetic brush charging device 7 using magnetic particles as a charging member. Specifically, as a charging member, a magnetic brush portion formed by magnetically constraining conductive magnetic particles is formed, and the magnetic brush portion is brought into contact with the photosensitive drum 4, and a voltage is applied to the magnetic brush portion to thereby form a photosensitive member. Charged.

Such a charging method (charging of a member to be charged by direct injection of charges) is called an injection charging method. By using this injection charging method, the photosensitive drum 4
A cleaner mechanism (cleaning blade, cleaning roller, etc.) for mechanically scraping and removing the transfer residual toner on the upper surface is not required. This cleanerless system will be described later. In addition, the injection charging method of the present embodiment does not utilize a discharge phenomenon in which charging of the charged object is performed using a corona charger, and therefore, the applied charging bias required for charging is adjusted to the desired charged object surface. Potential only,
It is a completely ozone-free and low-power-consumption type charging without generation of ozone.

Next, the magnetic brush charging device 7 of this embodiment
Will be described in detail with reference to FIG. The magnetic brush charging device 7 forms a magnetic brush portion of magnetic particles on a charging sleeve 9 containing a magnet roller 10 and charges the photosensitive drum 4 to a desired potential at a contact portion of the brush with the photosensitive drum 4. I have.

The charging sleeve 9 is disposed at the opening of the charging container 8 containing the magnetic particles so as to protrude to the outside with a substantially left half-peripheral surface protruding over the longitudinal direction. A stirring member 13 is disposed in the charging container substantially in parallel with the charging sleeve 9. The stirring member 13 is disposed above the charging sleeve 9, and is rotatably supported by bearings between wall surfaces at both ends in the longitudinal direction.

On the surface of the charging sleeve 9, moderately rough irregularities are formed in order to carry the magnetic particles well.
Magnet roller 10 provided inside charging sleeve 9
Has four poles magnetized in the circumferential direction. The magnet roller 10 is fixed so that one magnetic pole faces the center of the photosensitive drum 4 in order to prevent the magnetic particles from adhering to the photosensitive drum 4 and being carried along with the rotation.

At a predetermined distance from the surface of the charging sleeve 9, a non-magnetic plate-shaped regulating blade 11 is supported by the charging container 8 via a supporting metal plate 12. When the magnetic particles are held by the magnet roller 10 and conveyed in the direction of arrow B by the rotation of the charging sleeve 9, the magnetic particles are regulated to a predetermined thickness by the regulating blade 11, and a magnetic brush portion is formed on the charging sleeve 9. The charging sleeve 9 is opposed to the photosensitive drum 4 at a predetermined interval, and a magnetic brush portion formed on the charging sleeve 9 is brought into contact with the surface of the photosensitive drum 4 to form a charging nip portion. The width of the charging nip has an effect on the charging property of the photosensitive drum 4, and in the present embodiment, the interval is adjusted so that the width of the nip is about 6 mm.

A predetermined charging bias is applied to the magnetic brush unit from a charging bias power supply (not shown) via a charging sleeve 9, and the surface of the photosensitive drum 4 is contact-charged to a predetermined polarity and potential at a charging nip. As the magnetic particles constituting the magnetic brush portion, magnetic metal particles such as ferrite and magnetite, and those obtained by binding these magnetic particles with a resin can be used.

The charging sleeve 9 is rotated by a motor (not shown) in the direction of the arrow B which is a counter direction at the opposing portion with respect to the rotation of the photosensitive drum 4 as the charged body in the direction of the arrow A. In the present embodiment, the charging sleeve 9 is rotated in the counter direction at a speed ratio of V2 ≒ 1.5 × V1 with respect to the rotation speed V1 of the photosensitive drum 4. As the relative rotation speed between the photosensitive drum 4 and the magnetic brush portion increases, the chance of contact increases, so that the charging uniformity becomes better and the transferability of the transfer residual toner to the magnetic brush tends to be improved.

A charging brush 14 is disposed upstream of the charging sleeve 9 of the photosensitive drum 4.
A predetermined voltage is applied by contacting the surface with an approach amount of about 1 mm. By the contact of the charging brush 14, the transfer residual toner on the photosensitive drum 4 is evenly scattered, and further the charge is removed, so that the charging in the next step is performed uniformly.

(Exposure Means) Exposure to the photosensitive drum 4 uniformly charged as described above uses laser exposure means 2Y, 2M, 2C and 2K (laser beam optical scanning system) in the present embodiment. Have gone. That is, the device body 1
When an image signal is transmitted from the photosensitive drum 4, the laser beam L modulated according to the signal is scanned and exposed on the uniformly charged surface of the photosensitive drum 4 (see FIG. 6), and the laser light L corresponding to the image information is formed on the photosensitive drum 4. The formed electrostatic latent image is selectively formed.

As shown in FIG. 6, the laser exposure means 2 has a solid laser element (not shown), a polygon mirror 2a, an imaging lens 2b, and a reflection mirror 2c. When the solid-state laser element is turned on / off at a predetermined timing by a light-emitting signal generator (not shown) based on the input image signal, the laser light L emitted from the solid-state laser element becomes substantially parallel by a collimator lens system (not shown). The light is converted into a light beam and scanned by the polygon mirror 2a rotating at a high speed. Then, an image is formed in a spot shape on the photosensitive drum 4 via the imaging lens 2b and the reflection mirror 2c.

In this manner, on the photosensitive drum 4, exposure in the main scanning direction by laser beam scanning and exposure in the sub-scanning direction by rotation of the photosensitive drum 4 are performed, and an exposure distribution according to an image signal is obtained. . That is, by the irradiation and non-irradiation of the laser beam L, a bright portion potential whose surface potential is lowered and a dark portion potential which is not the same are formed. Then, an electrostatic latent image corresponding to the image information is formed by the contrast between the bright portion potential and the dark portion potential.

(Developing means) Developing device 15 as developing means
Is a two-component contact developing device (two-component magnetic brush developing device)
A two-component developer composed of a carrier and a toner is held on a developing sleeve 17, which is a developer carrying member including a magnet roller 18. A regulating blade 19 is provided on the developing sleeve 17 at a predetermined interval, and a thin layer developer is formed on the developing sleeve 17 as the developing sleeve 17 rotates in the direction of arrow C. The regulating blade 19 is fixedly supported by the developing container 16. The developing sleeve 17 is arranged in parallel with the photosensitive drum 4 at a predetermined interval, and is set so that the developer layer formed on the developing sleeve 17 can be developed in contact with the photosensitive drum 4 during development. Have been. The developing sleeve 17 is rotated at a predetermined speed in a direction indicated by an arrow C which is a counter direction to the rotation direction of the photosensitive drum 4 in the developing section.

The developer accommodating section 20 in which the developer is circulated,
As shown in FIG. 3 and FIG. 10, except for both ends, the partition is divided into two by a longitudinal partition 21. And stirring screw
22a and 22b are arranged with the partition wall 21 interposed therebetween. The stirring screws 22a and 22b are rotatably supported on both sides of the frame 24 of the process cartridge 3 via bearings 23 (see FIG. 10).

A supply port is provided at the upper part of the process cartridge 3.
The toner replenished from a toner replenishing container 50 described below falls to the front side of the stirring screw 22b, is conveyed to the rear side in the longitudinal direction while being agitated with the carrier, and forms Pass through the unoccupied portion 21a. Then, it is further conveyed to the near side in the longitudinal direction by the stirring screw 22a, passes through the portion 21b without the partition 21 on the near side, and is conveyed to the stirring screw 22b to repeat the circulation.

A description will now be given of a developing process for visualizing the electrostatic latent image formed on the photosensitive drum 4 by the two-component magnetic brush method using the developing device 15 and a developer circulation system.

As the developing sleeve 17 rotates, the developing container 16
The developer inside is pumped by the N3 pole of the magnet roller 18 onto the surface of the developing sleeve 17 and transported. In the course of the transport, the layer thickness of the developer is regulated by a regulating blade 19 arranged perpendicular to the developing sleeve 17, and a thin layer developer is formed on the developing sleeve 17. When the thin layer developer is conveyed to the developing pole N1 corresponding to the developing section, a spike is formed by magnetic force. The electrostatic latent image on the surface of the photosensitive drum 4 is developed as a toner image by the toner in the developer formed in the spike shape. In the present embodiment, the electrostatic latent image is reversely developed.

The thin layer developer on the developing sleeve 17 that has passed through the developing section enters the developing container 16 with the rotation of the developing sleeve 17 and is separated from the developing sleeve 17 by the repelling magnetic field of N2 pole and N3 pole. Then, the developer is returned to the developer reservoir in the developing container 16. A direct current (DC) voltage and an alternating current (AC) voltage are applied to the developing sleeve 17 from a power supply (not shown). In the present embodiment, a DC voltage of -500 V and an AC voltage of a peak-to-peak voltage of 1500 V at a frequency of 2000 Hz are applied to selectively develop only the exposed portion of the photosensitive drum 4.

In general, in the two-component developing method, when an AC voltage is applied, the developing efficiency is increased and the quality of an image is high, but on the contrary, there is a risk that fogging is likely to occur. For this reason, fogging is prevented by providing a potential difference between the DC voltage applied to the developing sleeve 17 and the surface potential of the photosensitive drum 4. More specifically, a bias voltage having a potential between the potential of the exposed portion of the photosensitive drum 4 and the potential of the non-exposed portion is applied. The potential difference for preventing fogging is called a fogging potential (V back). The potential difference prevents toner from adhering to a non-image area (non-exposed portion) on the photosensitive drum 4 during development, and also eliminates the need for a cleaner. The apparatus of the system also collects transfer residual toner on the photosensitive drum 4 (simultaneous cleaning with development).

When the toner is consumed by the development, the toner concentration in the developer decreases. In the present embodiment, a density detection sensor 26 for detecting the density of the toner is disposed at a position close to the outer peripheral surface of the stirring screw 22b, and it is determined that the density of the toner in the developer has dropped below a predetermined density level. When the density detection sensor 26 detects, a command to supply toner from the toner supply container 50 into the developing device 15 is issued. By this toner replenishing operation, the toner concentration of the developer is constantly maintained at a predetermined level.

(Cleanerless System) Next, a description will be given of a cleanerless system in a reversal developing system in which the photosensitive drum 4 is negatively charged and the negatively charged toner is developed on the low potential portion of the exposed portion. First, of the transfer residual toner slightly remaining on the photosensitive drum 4 after the transfer, the toner having a particularly positive charge is temporarily taken into the magnetic brush charging device 7 once, and is forcibly scraped by a brush. Collect other items. After being charged to a negative polarity by friction with the magnetic particles in the magnetic brush charging device 7, the toner is discharged onto the photosensitive drum 4.

On the other hand, the negatively charged toner among the transfer residual toner is hardly taken into the magnetic brush charging device 7 and is collected by the developing device 15 together with the toner discharged from the magnetic brush charging device 7 (development). Simultaneous cleaning). The toner is taken into the developing device 15 in the simultaneous development cleaning by a fog removal bias (a fog removal potential difference which is a potential difference between the DC voltage applied to the development device and the surface potential of the photosensitive drum 4).

According to this method, the transfer residual toner is partially collected via the magnetic brush charging device, and the remainder is directly collected by the developing device and used for the next process and thereafter, eliminating waste toner.
Maintenance work can be reduced. In addition, the cleaner-less system has a great advantage in terms of space, and can significantly reduce the size of the image forming apparatus.

(Transfer Means) The intermediate transfer unit 27 serving as a transfer means is for collectively secondary-transferring a plurality of toner images, which are sequentially primary-transferred from the photosensitive drum 4 and superimposed, collectively to the recording medium P. The intermediate transfer unit 27 includes an intermediate transfer belt 28 that runs in the direction of arrow D as shown in FIG. 2 and runs at a peripheral speed substantially equal to the outer peripheral speed of the photosensitive drum 4. The intermediate transfer belt 28 is an endless belt having a circumference of about 940 mm, and is stretched by a driving roller 29, a driven roller 30, and a secondary transfer facing roller 31.

Further, in the intermediate transfer belt 28, transfer charging rollers 32Y, 32M, 32C and 32K are rotatably disposed at positions facing the photosensitive drum 4, respectively, and are pressed toward the center of the photosensitive drum 4. The transfer charging roller 32 is supplied with power from a high-voltage power supply (not shown), charges the toner from the back side of the intermediate transfer belt 28 with a polarity opposite to that of the toner, and primarily transfers the toner image on the photosensitive drum 4 to the upper surface of the intermediate transfer belt 28 sequentially.

A secondary transfer roller 33 as a transfer member is pressed against the secondary transfer section at a position facing the secondary transfer opposing roller 31. The secondary transfer roller 33 is configured to be swingable up and down in the figure and rotatable. At this time, a bias is applied to the intermediate transfer belt 28 at the same time, so that the toner image on the intermediate transfer belt 28 is transferred to the recording medium P. The intermediate transfer belt 28 and the secondary transfer roller 33 are independently driven.

When the recording medium P enters the secondary transfer section, a predetermined bias is applied to the secondary transfer roller 33, and the toner image on the intermediate transfer belt 28 is secondarily transferred to the recording medium P.
At this time, the recording medium P sandwiched between the two is conveyed at a predetermined speed to the left in the figure at the same time as the transfer process is performed, and is conveyed to the fixing device which is the next process.

The intermediate transfer belt at the most downstream side of the transfer process
A cleaning unit 34 is provided at a predetermined position of the intermediate transfer belt 28 and is detachable from the surface of the intermediate transfer belt 28, and removes transfer residual toner remaining on the intermediate transfer belt 28 after the secondary transfer.
In the cleaning unit 34, a cleaning blade 34a for removing transfer residual toner is disposed. The cleaning unit is swingably attached to a rotation center (not shown), and is in pressure contact with the intermediate transfer belt 28 in a direction in which the cleaning unit bites. The transfer residual toner taken into the cleaning unit 34 is conveyed to a waste toner tank (not shown) by the feed screw 34b and stored therein.

Here, as the intermediate transfer belt 28, a belt made of a polyimide resin can be used. Other materials are not limited to polyimide resin,
It is preferable to use a plastic such as polycarbonate resin, polyethylene terephthalate resin, polyvinylidene fluoride resin, polyethylene naphthalate resin, polyether ether ketone resin, polyether sulfone resin, polyurethane resin, or a fluorine-based or silicon-based rubber. it can.

(Sheet Conveying Means) The sheet conveying means 35 is for feeding the recording medium P to the image forming section, and mainly comprises a feeding cassette 36 in which a plurality of recording media P are stacked and stored, and a feeding roller 37. And a retard roller 38 for preventing double feeding, a feeding guide 39, a pair of registration rollers 42, and the like. The feed roller 37 is driven and rotated in accordance with the image forming operation, and separates and feeds the recording media P in the feed cassette 36 one by one. The recording medium P is guided by a feeding guide 39, and is conveyed to a registration roller pair 42 via conveyance roller pairs 40 and 41.
Immediately after the recording medium P is conveyed, the registration roller pair 42 stops rotating, and the recording medium P is skewed by hitting the nip portion.

During the image forming operation, the registration roller pair 42
A rotation operation for causing the recording medium P to stand still and a rotation operation for conveying the recording medium P toward the intermediate transfer belt 28 are performed in a predetermined sequence, and the toner image and the recording medium during the next transfer step, the transfer step, are performed. Align with P. When the toner image is transferred to the recording medium P in the secondary transfer section as described above, the toner image is conveyed to the fixing device by driving the intermediate transfer belt 28 and the secondary transfer roller 33.

(Fixing Device) The fixing device 43 fixes the toner image transferred on the recording medium P to the recording medium P by applying heat and pressure. As shown in FIG. 2, the fixing device 43 includes a fixing roller 44 for applying heat to the recording medium P, and a recording medium P.
And a pressure roller 45 for pressing the fixing roller against the fixing roller. The fixing roller 44 and the pressure roller 45 are hollow rollers, each having a heater (not shown) inside thereof,
The recording medium P is nipped and conveyed by being rotationally driven.

That is, the recording medium P holding the toner image is conveyed by the fixing roller 44 and the pressing roller 45, and the toner image is fixed on the recording medium P by applying heat and pressure. The recording medium P after the fixing is discharged by discharge rollers 46 and 47, and a discharge tray on the apparatus main body 1.
Discharged and loaded at 48.

(Developer Supply Container) Next, the developer supply container according to the present invention will be described with reference to FIGS. 2, 4, 5, 7, 8, and 9.
This will be described with reference to FIG. The toner supply containers 50Y, 50M, 50C, and 50K, which are developer supply containers, are arranged in parallel above the process cartridges 3Y, 3M, 3C, and 3K.
It is configured to be detachable from the front of the apparatus main body 1 (see FIG. 1).

As shown in FIG. 4, the toner replenishing container 50 includes a toner container 52 as a developer container for storing the toner inside the frame 51 and a developer conveying unit for conveying the toner to the discharge port 53a. The toner conveying unit 54 is provided, and the toner storage unit 52 and the toner conveying unit 54 are separated by a partition plate 55 formed using a resin sheet member. Then, as shown in FIG. 8, the toner storage section 52 and the toner transport section 54 communicate with each other only at a receiving port 55a provided at one end of the partition plate 55.

On the other hand, a stirring shaft 56 serving as a developer stirring means and a stirring plate
A screw 58, which is a developer conveying means, is disposed in the toner conveying section 54 as a second rotating member, and a discharge port 53a for discharging toner is provided on the bottom surface of the container of the toner conveying section 54.
Is formed. Screw 58
The stirring shaft 56 is rotatably supported at both ends by bearings 59,
Drive coupling (concave) 60 at one end
a and 60b are fixedly arranged. The drive couplings (concave) 60a, 60b receive drive transmission from the drive couplings (convex) 61a, 61b of the apparatus main body 1, respectively, and are driven to rotate in accordance with a command issued by the density detection sensor 26 of the developing device 15.

The stirring plate 57 is formed of a flexible sheet member (for example, polyethylene terephthalate).
By tilting the tip of the rotation radius 57 in the axial direction (see FIG. 7), the tip rubs at a predetermined angle against the arc of the bottom surface of the toner supply container 50 (the bottom surface of the toner container 52). Make up. Specifically, the tip side of the stirring plate 57 is twisted into a spiral state, and the twisting and tilting generates a conveying force in the axial direction of the stirring shaft 56, so that the toner is conveyed in the longitudinal direction. The inclination of the tip of the stirring plate 57 is formed in a substantially symmetrical shape around the receiving port 55a, and the toner inside the toner storage section 52 is transported toward the receiving port 55a, which is a communication section with the toner transport section 54. You. Entrance
The toner conveyed to 55a is sent to the toner conveying section 54 by free fall.

The outer shape of the screw 58 is formed in a spiral rib shape, and the twist direction of the spiral is reversed around the discharge opening 53 (see FIG. 8). And screw 58
Is driven by the rotation of the drive coupling (convex) 61b, the toner is conveyed toward the discharge opening 53, the toner is freely dropped from the discharge port 53a of the discharge opening 53, and the supply port 25 is supplied to the process cartridge 3. Replenish the toner via.

When the toner in the toner supply container 50 is estimated to be in a reduced state, the toner in the vicinity of the discharge opening 53 is positively discharged, and the toner decreases conically. Such non-uniform toner reduction is considered undesirable in discharging a certain amount of toner. Therefore, in the present embodiment, the toner is stably discharged by conveying the toner to the discharge opening 53 by the stirring plate 57 as described above.

The toner supply container according to the present embodiment is not limited to the two-component developing method, but can be supplied to a process cartridge or a developing cartridge using a one-component developing method. The body is not limited to toner, and may be a so-called developer in which toner and a magnetic carrier are mixed.

(Mounting of Process Cartridge and Developer Supply Container) Next, attachment and detachment of the process cartridge 3 and the toner supply container 50 will be described with reference to FIGS. 1, 6, 8, and 9. FIG. As shown in FIG. 1, a front door 62 that can be opened and closed is provided at the front of the apparatus main body 1. When the front door 62 is opened to the front, an opening 1a into which the process cartridge 3 and the toner supply container 50 are inserted. , 1b are exposed. A centering plate 63 rotatably supported is disposed in the opening 1b into which the process cartridge 3 is inserted. When the process cartridge 3 is attached and detached, the centering plate 63 is opened and closed.

As shown in FIG. 6, a guide rail 64 for guiding the mounting and dismounting of the process cartridge 3 is provided in the apparatus main body 1.
A guide rail 65 for guiding the mounting of the toner supply container 50 is fixed. The mounting direction of the process cartridge 3 is a direction parallel to the axial direction of the photosensitive drum 4, the mounting direction of the toner supply container 50 is a direction parallel to the axial direction of the screw 58, and the guide rails 64 and 65 are in the same direction. Are located in Then, the process cartridge 3 and the toner supply container are temporarily moved along the guide rails 64 and 65 to the apparatus main body 1.
Is slid from the front to the back and inserted.

When the process cartridge 3 is inserted to the innermost part, the inner end of the drum shaft 4a is inserted into the centering shaft 66 of the apparatus main body 1 as shown in FIG. The rotation center is determined with respect to the apparatus main body 1. At the same time, the drum flange 4b and the drive coupling (convex) 61c are connected, so that the photosensitive drum 4 can be driven to rotate. Further, a support pin 67a for positioning the rear side plate 1d of the process cartridge 3 is arranged, and the position of the process cartridge 3 is fixed by being inserted into a concave portion 3b provided in the frame 3a of the process cartridge 3. On the front side of the apparatus body 1, a centering plate
By closing 63, the bearing case 4c of the photosensitive drum 4
Is supported and fixed.

By a series of these inserting operations, the process cartridge 3 and the photosensitive drum 4 are positioned with respect to the apparatus main body. That is, the drum shaft 4a, the drum flange 4b, the concave portion 3b, and the bearing case 4c constitute a positioning portion for positioning the process cartridge 3 on the apparatus main body 1.

On the other hand, when the toner supply container 50 is inserted to the innermost portion, the support pins 67b projecting from the rear plate 1d are inserted into the concave portions 51a provided on the inner side of the frame 51 as shown in FIG. The reference position of the supply container 50 is determined. Similarly, the support pins 67c provided on the rear side plate 1d
The toner supply container 50 is inserted into a concave portion 51b provided on the inner side of the toner supply container 50, and the position of the frame 51 of the toner supply container 50 is fixed. At the same time, the drive coupling (concave) 60a, 60
b and the drive couplings (convex) 61a, 61b are connected, so that the screw 58 and the stirring shaft 56 can be rotationally driven.

A support pin is provided on the front side plate 1c of the apparatus main body 1.
67d is provided, and the position on the near side of the toner supply container 50 is determined by engagement with a concave portion 68a provided in a holder 68 attached to the toner supply container 50. That is, the support pins 67b, 67c, 67d and the recesses 51a, 51b, 68a constitute a positioning portion for positioning the toner supply container 50 in the apparatus main body 1, and the drive couplings (recesses) 60a, 60
b and the drive couplings (convex) 61a and 61b transmit the drive.

(Drive Load in Positioning Section of Toner Replenishing Container) Next, the load applied to the concave portion 51a as the positioning section of the toner replenishing container 50 will be described with reference to FIG. FIG. 7 is a side view of the inner side of the toner supply container 50. As shown in the figure, the toner supply container is positioned by concave portions 51a, b, 68a arranged on the same straight line with respect to the apparatus main body 1, and the concave portion 51a is used as a reference.

The concave portions 51a and 51b serving as the positioning references have rotational moments α and β of the stirring shaft 56 and the screw 58, respectively.
Respectively generate loads F1 and F2, and the combined load F
Is working. In order to make the combined load F as small as possible, it is desirable to dispose the concave portion 51a at a position where the loads F1 and F2 cancel each other. Accordingly, a straight line between the rotation center of the stirring shaft 56 and the rotation center of the screw 58 and connecting the rotation center of the screw 58 and the recess 51a and a straight line connecting the rotation center of the stirring shaft 56 and the center of the recess 51a. The angle formed is 16
By arranging at a position where the angle becomes 0 °, the combined load F can be reduced.

In the arrangement of the rotation center of the recess 51a, the stirring shaft 56 and the screw 58 in this embodiment, for example, α,
If the rotational moment of β is the same, the combined load F
Is about 40% of the load F1. During actual use, the relationship between the rotational moments α and β does not always match because the amount of residual toner in the toner supply container 50 changes as needed, but the load is always imposed on the stirring shaft 56 and the screw 58 due to the sliding resistance of the bearing 59, etc. Therefore, the loads F1 and F2 always cancel each other by adopting the arrangement of our school.

In order to satisfy the relationship of canceling the load, the angle formed by the straight line connecting the rotation center of the screw 58 and the recess 51a and the straight line connecting the rotation center of the stirring shaft 56 and the center of the recess 51a must be formed. Must be at least 120 °. The reason will be described with reference to FIGS. 11, 12, and 13. FIG.

FIG. 11 is a diagram showing a state in which the angle θ formed by the load is 120 °. First, the center at which a load is applied (the concave portion 51a in this embodiment) is O. Then, it is assumed that the relationship between the loads f1 and f2 applied to the center O is f1 ≧ f2. When the angle θ between the load f1 and the load f2 is 120 °, the resultant force f is in the range of ΔOAB,
The resultant force f becomes maximum when f1 = f2, and the relationship of f = f1 = f2 holds. Similarly, when f1 ≦ f2, the resultant force f is in the range of ΔOCB. That is, when θ = 120 °, f does not become larger than the load on the side where the load f1 or f2 is larger.

Next, FIG. 12 shows that the angle θ formed by the load is 0 ° ≦ θ ′.
It is a figure showing a state of <120 degrees. Assuming that the load applied to the center O is f1 and f2 ′ in the same manner as in FIG. 11, f1 ≧ f2 ′
The resultant force f ′ is within ΔOAB ′. Where f 'is θ = 120
As in the case of °, it becomes maximum when f1 = f2 ', but at this time,
f ′> f1 = f2 ′, and a load greater than f1 is applied to the center O.

FIG. 13 shows that the angle θ formed by the load is 12
It is a figure which shows the state of 0 degree <theta "<= 180 degree.
1, the load applied to the center O is f1 and f2 "as in FIG. 12. Similarly, the resultant force f" when f1 ≧ f2 "is within ΔOAB" and f1 = f2 ".
At the time, f "becomes the maximum, but at this time, f"<f1 = f2 ", and
The load applied to O always has a relationship of canceling each other.

As described above, the loads F1 and F2 applied to the reference positioning recess 51a are caused by the rotational moments α and β of the two rotating bodies (the stirring shaft 56 and the screw 58 in this embodiment) inside the toner supply container 50. Since the relations cancel each other, the positioning portions can be accurately positioned without bending of the positioning portion due to the loads F1 and F2.

[Other Embodiments] In the above embodiment, the configuration in which the toner supply container 50 has the two rotating members of the stirring shaft 56 and the screw 58 has been described, but the configuration has two or more rotating members. Also, the effect of the present invention can be obtained if the configuration has two drive transmission units.

In the above embodiment, the toner supply container
Although the coupling mechanism is used as the drive transmission means of the rotating body in 50, the same effect can be obtained with a gear mechanism. Further, in the present embodiment, the supply port 25 is provided in the detachable process cartridge, but may be provided in, for example, a toner buffer fixed in the apparatus main body.

[0075]

As described above, in the developer supply container and the image forming apparatus according to the present invention, the two drive transmission means are rotated in the same direction, and the two drive transmission means are positioned between the rotation centers of the two drive transmission means. By arranging the parts, and by configuring the interior angle of a straight line connecting the positioning part and the rotation center of each drive transmission means to be 120 ° or more and 180 ° or less, the load applied to the positioning part is offset. Therefore, it is possible to reduce the deflection of the toner supply container and accurately position the toner supply container.

The above configuration is realized by the rotation directions of the two drive means and the arrangement of the two drive transmission means and the positioning means, which leads to an increase in production costs such as addition of new parts and increase in strength of the parts. It is possible to improve the positioning accuracy without the need.

In addition, since the positioning accuracy is improved in this manner, the displacement between the discharge port of the developer supply container and the supply port on the apparatus main body side can be minimized, so that the apparatus main body can be downsized. It can be.

[Brief description of the drawings]

FIG. 1 is an external perspective view of an image forming apparatus according to an embodiment.

FIG. 2 is an overall configuration diagram of the image forming apparatus according to the embodiment.

FIG. 3 is a diagram illustrating a configuration of a process cartridge.

FIG. 4 is a longitudinal sectional view of a developer supply container.

FIG. 5 is an external perspective view of a developer supply container.

FIG. 6 is a diagram illustrating a state in which a developer supply container is mounted on a process cartridge.

FIG. 7 is a side view of the back side of the toner supply container 50.

FIG. 8 is a longitudinal sectional view of the developer supply container.

FIG. 9 is an enlarged view near the discharge port.

FIG. 10 is a longitudinal sectional view of the process cartridge.

FIG. 11 is a diagram illustrating a combined load based on an angle formed by the load.

FIG. 12 is a diagram illustrating a combined load based on an angle formed by the load.

FIG. 13 is a diagram illustrating a combined load based on an angle formed by the load.

[Explanation of symbols]

 F: Synthetic load L: Laser beam P: Recording medium 1: Image forming apparatus 1a, b: Opening 2: Laser exposure means 2a: Polygon mirror 2b: Image forming lens 2c: Reflecting mirror 3: Process cartridge 3a: Frame 4 ... Photosensitive drum 4a drum shaft 4b drum flange 4c bearing case 4d non-drive flange 4e bearing 5 charging means 6 developing means 7 magnetic brush charging device 8 charging container 9 charging sleeve 10 magnet roller 11 Control blade 12 ... Support metal plate 13 ... Stirring member 14 ... Charging brush 15 ... Developing device 16 ... Developing container 17 ... Developing sleeve 18 ... Magnetic roller 19 ... Regulator blade 20 ... Developer storage section 21 ... Partition walls 22a, b ... Stirring screw 23 … Bearing 24… Frame 25… Supply port 26… Density detection sensor 27… Intermediate transfer unit 28… Intermediate transfer base G 29… Drive roller 30… Driving roller 31… Secondary transfer opposed roller 32… Transfer charging roller 33… Secondary transfer roller 34… Cleaning unit 35… Sheet conveying means 36… Feed cassette 37… Feed roller 38… Retard roller 39… Feeding guides 40, 41… Conveying roller pair 42… Registration roller pair 43… Fixing device 44… Fixing roller 45… Pressure roller 46, 47… Discharge roller 48… Discharge tray 50… Toner supply container 51… Frame 51a, b: recess 52: toner container 53: discharge opening 53a: discharge port 54: toner transport section 55: partition plate 55a: receiving port 56: stirring shaft 57: stirring plate 58: screw 59: bearing 60: drive coupling ( (Concave) 61 ... drive coupling (convex) 62 ... front door 63 ... centering plate 64, 65 ... guide rails 67a-d ... support pins

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Akira Fujita 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term within Canon Inc. (reference) 2H077 AA02 AA05 AB03 AB04 AB06 AB12 AC02 AD06 BA02 EA03 FA19

Claims (7)

[Claims] 1. A positioning section for attaching to at least an apparatus main body, a developer accommodating section for accommodating a developer, an outlet for discharging the developer accommodated in the developer accommodating section, and a plurality of rotating members. A developer supply container for supplying a developer to the developing means of the electrophotographic image forming apparatus, the developer supply container having two drive transmitting means for transmitting a driving force to the rotating member; And the positioning portion is disposed between the rotation centers of the two drive transmission means, and the interior angle of a straight line connecting the positioning portion and the rotation center of each drive transmission means is 120 °. A developer supply container characterized by being configured to be at least 180 ° or less. 2. The developer supply container according to claim 1, wherein at least one of said rotating members is a developer stirring means disposed in said developer accommodating portion. 3. The developer supply container according to claim 1, wherein at least one of said rotating members is a developer conveying means. 4. At least one of said drive transmission means,
The developer supply container according to claim 1, wherein the developer supply container is a coupling mechanism. 5. At least one of the war driving drive means,
The developer supply container according to claim 1, wherein the developer supply container is a gear mechanism. 6. A developer supply container according to claim 1, an image carrier for carrying an electrostatic latent image, and an electrostatic latent image on the image carrier by a developer supplied from the developer supply container. An image forming apparatus comprising: developing means for developing a sheet; transfer means for transferring a developer image developed on a sheet; and sheet conveying means for conveying the sheet. 7. The image forming apparatus according to claim 6, wherein the developer supply container is configured to be detachable from an apparatus main body.