JP3861429B2 - Toner supply device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a toner replenishing device that replenishes toner in a toner storage container to a toner storage unit by mounting a toner storage container containing toner in a cylindrical container body and rotating the toner storage container.
[0002]
[Prior art]
Conventionally, as means for supplying toner from a toner storage container (toner cartridge) for storing toner to a toner storage portion of an image forming apparatus, the toner storage container is set in the apparatus body when toner is supplied. There is a type in which all toner is supplied to the toner storage unit, and the toner container is removed from the apparatus main body after the supply is completed. However, in the above-described type of replenishment method, in order to replenish toner to the toner storage unit at once, the toner may overflow and the toner may overflow from the toner storage unit. .
[0003]
It is difficult to prevent the toner from being excessively replenished, and even if a means for preventing the excessive replenishment can be installed in the main body of the apparatus, the apparatus is expensive and large. Therefore, a toner storage container having a spiral protrusion inside the container is set with respect to the apparatus main body, rotated around the central axis of the toner storage container, and the toner is discharged from the toner discharge port of the toner storage container. A type that replenishes toner in a storage unit has been developed (JP-A-7-295356, etc.). In this type, the toner storage container is always installed in the main body of the apparatus, so that when the toner in the toner storage section decreases, the toner storage container can be rotated at any time to supply toner to the toner storage section. Therefore, it is no longer necessary to prevent oversupply of toner as described above.
[0004]
[Problems to be solved by the invention]
The toner storage container and the toner replenishing device equipped with the toner storage container have been raised as issues to be considered as to how efficiently toner in the toner storage container can be supplied to the toner storage unit.
[0005]
An object of the present invention is to solve the above-described problems in a toner storage container and a toner replenishing device that supplies toner from the toner storage container to the developing device.
[0006]
[Means for Solving the Problems]
A toner storage container that discharges toner from an opening provided on the outer peripheral surface of the container body by rotating the toner stored in a cylindrical container body having a spiral protrusion inside, and the toner storage container is mounted. A toner guide means for guiding the inside of a toner conveyance path having a paddle portion that receives, scrapes, and pushes out toner from an opening provided at a position facing the opening of the toner storage container, and discharges the toner from a toner supply port ; A toner storage section for receiving and storing the toner discharged from the toner supply port of the toner guide means, and rotating the mounted toner storage container to rotate the toner from the opening of the toner storage container. transported to the toner replenishing port by guiding means, to supply the toner to drop the toner to the toner reservoir through the toner supply opening of said toner guide means It is an butterfly.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Prior to the description of the embodiment of the present invention, the configuration and operation of a color printer, which is an example of a color image forming apparatus in which a plurality of toner replenishing devices and developing devices according to the present invention are mounted, will be described with reference to the cross-sectional configuration diagram of FIG. To do.
[0008]
In this color printer, the respective color toner images sequentially formed on the image forming body are superposed, and then transferred onto the recording paper at one time by the transfer unit to form a color image, and then separated from the surface of the image forming body by the separating means. This is a color image forming apparatus of a peeling type.
[0009]
In FIG. 1, reference numeral 10 denotes a photoconductive drum as an image forming body, which is formed by coating an OPC photoconductor (organic photoconductor) on a drum base, and is driven to rotate in the clockwise direction shown in the figure. 11 is a scorotron charger, provided by a corona discharge by a grid and the corona discharge wire which is the potential held at grid potential V _G uniform charging of the high voltage V _H to the photosensitive drum 10 peripheral surface. Prior to this charging by the scorotron charger 11, exposure by a PCL (pre-charging neutralizer) 12 using a light emitting diode or the like is performed to eliminate the history of the photosensitive member up to the previous printing, and the peripheral surface of the photosensitive member is discharged. deep.
[0010]
After the photosensitive drum 10 is uniformly charged, the image exposure unit 13 performs image exposure based on the image signal. The image exposure means 13 performs main scanning by bending the optical path by a reflection mirror 134 through a polygon mirror 131, an fθ lens 132, and a cylindrical lens 133 which are rotated by using a laser diode (not shown) as a light source, and the photosensitive drum 10 is rotated. A latent image is formed by (sub-scanning). In this embodiment, the character portion is exposed to form an inverted latent image in which the character portion has a lower potential V _L.
[0011]
On the periphery of the photosensitive drum 10, developing devices 20Y, 20M, and 20B each containing a two-component developer composed of a toner such as yellow (Y), magenta (M), cyan (C), and black (K) and a carrier. A developing device 20 comprising 20C and 20K is provided.
[0012]
First, yellow of the first color is developed by a developer carrying member (developing sleeve) 21 that contains a magnet and rotates while holding the developer. The developer consists of a carrier with a ferrite core and an insulating resin coating around it, and a toner containing polyester as a main material and a pigment according to the color and a charge control agent, silica, titanium oxide, etc. The developer is transported to the development zone on the developing sleeve 21 by the layer forming means with a developer layer thickness of 100 to 600 μm.
[0013]
As 0.2~1.0mm the developing sleeve 21 a gap between the photosensitive drum 10 is greater than the developer layer thickness in the developing zone, the AC bias V _AC Noto DC bias V _DC is applied to superimposed during which The Since the DC bias V _DC and the high potential V _H are charged with the same polarity, the toner that is triggered to leave the carrier by the AC bias V _AC is a portion of the high potential V _{H that has} a higher potential than the DC bias V _DC. Is attached to a low potential _VL portion having a potential lower than the DC bias _VDC and is visualized (reverse development).
[0014]
After the first color visualization is completed, the second color magenta image forming process is started, and uniform charging is performed again by the scorotron charger 11, and a latent image is formed by the second color image data by the image exposure means 13. Is done. At this time, the charge removal by the PCL 12 performed in the first color image forming process is not performed because the toner adhering to the image portion of the first color is scattered due to a rapid decrease in the surrounding potential.
[0015]
A latent image similar to that of the first color is formed and developed on the portion of the photosensitive member having the high potential V _H again over the entire surface of the photosensitive drum 10 where no image of the first color is present. However, in the portion where the development is performed again on the portion where the image of the first color is present, a latent image having the potential V _M ′ is formed by the toner attached to the first color by the light shielding and the charge of the toner itself, and the DC bias V _DC Development corresponding to the potential difference of the potential V _M ′ is performed. In the overlapping portion of the first color image and the second color image, if the development of the first color is performed by creating a latent image with a low potential _VL , the balance between the first color and the second color is lost, so the exposure amount of the first color is reduced. Thus, the intermediate potential may be set such that V _H > V _M ′> V _L.
[0016]
For the third color cyan and the fourth color black, an image forming process similar to that of the second color magenta is performed, and a four-color visible image is formed on the circumferential surface of the photosensitive drum 10.
[0017]
A toner replenishing device 40 that controls and replenishes each of the developing devices 20Y, 20M, 20C, and 20K with a new color toner attaches and detaches a plurality of toner storage containers (hereinafter referred to as storage containers) 30Y, 30M, 30C, and 30K. Storage container mounting portions 41Y, 41M, 41C, and 41K to be enabled, toner storage portions 47Y, 47M, 47C, and 47K that temporarily store toner in the storage containers 30Y, 30M, 30C, and 30K, and the toner storage portion 47Y , 47M, 47C, and 47K, toner conveying portions 48Y, 48M, 48C, and 48K that convey the toner to the developing devices 20Y, 20M, 20C, and 20K.
[0018]
On the other hand, one transfer material (transfer paper or the like) p carried out from the paper feed cassette 50 via the half-moon roller 51 temporarily stops near the registration roller pair 54 via the paper feed roller pair 52, 53, and is transferred. When the timing is correct, the registration roller pair 54 is rotated to feed the sheet to the transfer area.
[0019]
In the transfer area, the transfer means 60 is pressed against the peripheral surface of the photosensitive drum 10 in synchronism with the transfer timing, and the multi-color image is transferred in a lump by sandwiching the fed transfer material p.
[0020]
Next, the transfer material p is neutralized by the separating means 61, separated from the peripheral surface of the photosensitive drum 10, and conveyed to the fixing device 70, where the heat roller (upper roller) 71 and the pressure roller (lower roller) 72 are heated and heated. After the toner is welded by the pressure, the toner is discharged onto a discharge tray 83 outside the apparatus through discharge rollers 81 and 82. The transfer means 60 is retracted away from the peripheral surface of the photosensitive drum 10 after the transfer material p has passed, and prepares for the formation of the next toner image.
[0021]
On the other hand, the photosensitive drum 10 from which the transfer material p has been separated is subjected to static elimination by the static eliminator 14, and then the residual toner is removed and cleaned by pressure contact of the blade 151 of the cleaning device 15. 11 is charged, and the next image forming process starts. The blade 151 moves immediately after cleaning the photoreceptor surface and retracts from the circumferential surface of the photoreceptor drum 10. The waste toner scraped off into the cleaning device 15 by the blade 151 is discharged by the screw 152 and then stored in a waste toner collection container (not shown).
[0022]
FIG. 2 is a perspective view of the toner replenishing device 40 equipped with the toner storage containers 30Y, 30M, 30C, and 30K.
[0023]
The storage container mounting portions 41Y, 41M, 41C, and 41K of the toner replenishing device 40 each have four types of toner storage containers 30Y, 30M, 30C, and 30K installed in parallel on substantially the same plane to be detachable. The toner storage units 47Y, 47M, 47C, and 47K store the toner discharged from the toner storage containers 30Y, 30M, 30C, and 30K, and the amount of toner in the developing units 20Y, 20M, 20C, and 20K decreases. When this occurs, each toner is controlled and replenished.
[0024]
Since these toner storage containers 30Y, 30M, 30C, and 30K have substantially the same configuration, hereinafter, the toner storage containers 30Y, 30M, 30C, and 30K will be referred to as storage containers 30 and will be referred to as storage container mounting portions 41Y. , 41M, 41C, 41K will be referred to as the storage container mounting portion 41, and the toner storage portions 47Y, 47M, 47C, 47K will be referred to as the toner storage portion 47.
[0025]
3A is a cross-sectional view showing a state before the storage container 30 is mounted on the storage container mounting portion 41 of the toner replenishing device 40, that is, a state where the storage container mounting portion 41 and the storage container 30 are separated from each other. 3 (b) is a partially enlarged sectional view of the storage container 30, and FIG. 3 (c) is a partially enlarged sectional view of the storage container mounting portion 41.
[0026]
The storage container 30 has a cylindrical container main body 31 that stores toner therein, a fixing lid 32 that fixes an end surface of the container main body 31 in the rotation axis direction, and an elastic container whose one end is fixed to the container main body. An opening / closing lid 33 is included.
[0027]
An opening is provided in the protruding portion of one end surface of the container body 31 in the rotation axis direction, and the lid is closed and fixed by the fixed lid 32. On the inner peripheral surface of the container body 31, a guide part (toner guiding part) composed of a spiral projection 311 is formed. When the storage container 30 is rotated, the toner stored in the container body 31 is spiral. Is guided along the projection 311 and moved in the direction of the fixed lid 32.
[0028]
On the outer peripheral surface of the protruding portion of the container main body 31, a plurality of toners are discharged from the container main body 31 and stored and accumulated in the toner storage portion 47 via a storage container mounting portion 41 of a toner supply device 40 described later. The opening (toner discharge port) 312 is formed.
[0029]
A flat abutting portion 321 is formed on the end surface (left side in the figure) of the fixed lid 32, and comes into contact with a mounting portion opening / closing lid 44 of the storage container mounting portion 41 described later. Further, a ring-shaped protrusion 322 is integrally formed on the outer peripheral surface of the fixed lid 32, and a locking portion (free end) 331 in the vicinity of the left end of the container opening / closing lid 33 shown in the figure is detachably engaged. Match. An open surface at the right end of the container opening / closing lid 33 is a fixing portion (fixed end) 332 that is fixed in close contact with the outer peripheral surface of the container main body 31. The fixing portion 332 is integrated with the container opening / closing lid 33 by adhesion or welding.
[0030]
The container opening / closing lid 33 is made of, for example, blow-molded polyethylene resin and has flexibility. The outer periphery of the container opening / closing lid 33 is formed of a plurality of bellows and can be expanded and contracted in the direction of the rotation axis R. An inner space of the container opening / closing lid 33 forms a penetrating space.
[0031]
The storage container mounting portion 41 includes an outer cylinder member 42, an inner cylinder member 43, a retractable mounting portion opening / closing lid 44, a coil spring 45, and a storage container rotation gear 46. The outer cylinder member 42 and the inner cylinder member 43 are integrally formed, and constitute toner guide means for receiving and transporting the toner discharged from the storage container 30 and supplying it to the toner storage portion 47.
[0032]
A rotation shaft portion 421 on the left side of the outer cylinder member 42 is rotatably supported by two parallel upright walls 471 and 472 constituting the toner storage portion (toner hopper) 47. A storage container rotating gear 46 is fixed to the shaft end of the rotating shaft 421. The storage container rotating gear 46 is driven and rotated by a driving source (not shown).
[0033]
A through hole 422 is formed in the axial center portion of the rotary shaft portion 421 and is hollow. When the storage container 30 is mounted on the storage container mounting portion 41, the through-hole 422 allows the air in the mounting portion opening / closing lid 44 described later to be compressed by the abutting portion 321 at the distal end of the storage container 30. From the toner supply device 40.
[0034]
A plurality of openings (toner discharge ports) 431 are formed in the outer peripheral surface of the inner cylinder member 43. The opening 431 communicates with a toner conveyance passage 424 formed by the outer cylinder member 42 and the inner cylinder member 43, and further from the toner supply port 425 formed in the side surface of the outer cylinder member 42, the toner storage portion. 47.
[0035]
A locking projection 432 projecting inside the entrance portion of one end surface of the inner cylinder member 43 engages with a distal end portion (free end) 442 of the entrance of the mounting portion opening / closing lid 44 to prevent escape. . Further, the locking wall portion 433 on the other end surface of the inner cylinder member 43 is fixed (welded) by ultrasonic welding from a locking portion (fixed end) 443 on the back side of the mounting portion opening / closing lid 44. This fixation may be fixed with an adhesive.
[0036]
The mounting portion opening / closing lid 44 is made of, for example, blow-molded polyethylene resin and has flexibility. The outer periphery of the mounting portion opening / closing lid 44 is formed of a plurality of bellows and can be expanded and contracted in the direction of the rotation axis R. An inner space of the mounting portion opening / closing lid 44 forms a penetrating space. The coil spring 45 is loaded in the space so as to be extendable and contractible. The coil spring 45 extends and extends the mounting portion opening / closing lid 44 from the inside. The end portion on the entrance side of the mounting portion opening / closing lid 44 is urged by the coil spring 45, but is a free end that can be moved by an external force in the direction of the rotation center axis R.
[0037]
FIG. 4 is a cross-sectional view showing the toner replenishing device in a state where the storage container 30 is mounted on the storage container mounting portion 41, that is, the storage container 30, the storage container mounting portion 41, the toner storage portion 47, and the toner transport portion 48. 5 is a partially enlarged cross-sectional view of the storage container 30 and the storage container mounting portion 41, and FIG. 6 is a cross-sectional view taken along line AA of the storage container 30 and the storage container mounting portion 41 in FIG.
[0038]
The storage container 30 is gripped, placed on the guide base 411 of the storage container mounting portion 41 and moved to the left in the figure, and the foremost butting portion 321 of the storage container 30 is moved to the mounting portion opening / closing lid 44. Make contact with the right end face.
[0039]
When the storage container 30 is continuously moved in the direction of the arrow shown in FIG. 3, the convex portion 333 of the container opening / closing lid 33 abuts against the inlet wall surface 434 of the inner cylinder member 43 during the movement process of the storage container 30. And the bellows portion of the container opening / closing lid 33 is compressed, the engagement portion 331 of the container opening / closing lid 33 and the abutting portion 321 of the fixed lid 32 are disengaged and separated from each other, and the fixed lid 32 presses the mounting portion opening / closing lid 44. As a result, the mounting portion opening / closing lid 44 is compressed against the coil spring 45, the opening (toner discharge port) 431 is gradually opened, and the opening 431 is fully opened. The opening 431 in the fully open state is in phase with the opening 312 of the container main body 31 so that the toner in the container main body 31 can be discharged from the opening 312 to the opening 431.
[0040]
In FIG. 6, the container body 31 is provided with openings 312 at four locations and protrusions 313 at two locations on the outer periphery. The protrusion 313 fits into any of the four recesses 435 provided on the inner wall of the inner cylinder member 43. When the outer cylinder member 42 integrated with the inner cylinder member 43 is driven and rotated by the storage container rotation gear 46 connected to the drive source, the container body 31 connected to the recess 435 of the inner cylinder member 43 is driven. It is rotated.
[0041]
Four paddle portions 436 protrude in the vicinity of the opening portions 431 drilled at four locations of the inner cylinder member 43. The paddle portion 436 has a twist angle in the direction of the rotation center axis R, and smoothly discharges the toner conveyed in the toner conveyance path 424. The paddle portion (scraping portion) 436 scoops up the toner discharged from the opening 431, transports it in the toner transport passage 424, and discharges it from the toner supply port 425.
[0042]
The toner discharged from the toner supply port 425 passes through the opening 473 of the upright wall 471 of the toner storage unit 47 and is stored in the hopper.
[0043]
The amount of toner stored in the toner storage unit 47 is detected by light detection means (not shown). When the toner supply amount reaches a predetermined amount, the driving source is stopped and toner supply from the toner storage unit 47 is performed. To stop.
[0044]
The toner is rotated by the storage container 30 so that the toner is replenished to the toner storage unit 47. If the toner level in the toner storage unit 47 matches the height of the toner in the storage container 30, the storage container 30 Since toner is not replenished even if it rotates, even if the container 30 continues to rotate in this state, a problem such as toner clogging does not occur.
[0045]
The toner accommodated in the hopper of the toner storage unit 47 is sent to a conveyance screw 482 fixed to a conveyance screw gear 481 connected to a drive source (not shown), and is conveyed in the toner conveyance unit 48, and the developing device. 20 is replenished.
[0046]
3A and 4, a cover member 412 is fixedly disposed above the storage container 30, the storage container mounting part 41, and the toner storage part 47. On the entrance side of the cover member 412, a retaining member 413 having elasticity that prevents escape of the storage container 30 to be attached is fixed, and engages with the step portion 314 of the container body 31. The retaining member 413 may be formed integrally with a part of the cover member 412. Further, the retaining member 413 can also be used as an erroneous attachment preventing member when attaching the plurality of storage containers 30Y, 30M, 30C, 30K to the predetermined storage container mounting portions 41Y, 41M, 41C, 41K, respectively. Is possible.
[0047]
【The invention's effect】
(1) The invention described in claim 1 is an invention relating to a toner replenishing device for replenishing toner to a toner storage section by rotating a toner storage container. Toner guiding means for discharging toner from an opening provided on the outer surface of the toner container, guiding the toner from the vicinity of the outer surface of the toner container to the vicinity of the rotation center axis of the toner container, and discharging the toner to the toner storage unit Is installed. First, by providing an opening on the outer surface of the toner container, the toner is most efficiently discharged by the action of gravity when the toner container rotates, and can be discharged so as not to remain in the toner container. In addition, the structure of the toner storage container is simple, and the cost of the toner storage container to be replaced a plurality of times for supplying toner to the image forming apparatus can be reduced, which is effective for manufacturers and users. In addition, by installing the toner guiding means having the above-described structure, even when there is a toner storage part beside a toner storage container mounted for the purpose of downsizing the apparatus, the toner storage part is stored in the toner storage part. Therefore, it is possible to prevent problems such as image deterioration even while the toner in the toner container is reduced and replaced.
[0048]
(2) The invention described in claims 2 and 3 relates to an opening / closing lid. By installing an opening / closing lid in each opening, it is possible to prevent toner spillage when replacing the installed toner storage container, and the opening / closing lid opens and closes when the toner storage container is attached / detached. If this is done, the operation of opening and closing the open / close lid can be omitted, saving labor.
[0049]
(3) The invention described in claim 4 is an invention in which the toner guide means is provided with a drive transmission portion for transmitting the rotational force to the toner storage container. In this way, the space can be used effectively, and the device Can contribute to downsizing.
[0050]
(4) According to the fifth aspect of the present invention, the toner introduced from the opening of the toner guide unit into the toner conveyance path of the toner guide unit is scraped up and conveyed above the rotation center axis of the toner storage container. Since the toner can be dropped into the toner storage unit from a position higher than the rotation center axis of the storage container, a large amount of toner can be stored in the toner storage unit. Can be secured. Furthermore, it is possible to improve the stirring and replenishment efficiency of the toner.
[Brief description of the drawings]
FIG. 1 is a cross-sectional configuration diagram of a color printer which is an example of a color image forming apparatus in which a plurality of sets of toner replenishing devices and developing devices are mounted.
FIG. 2 is a perspective view of a toner replenishing device equipped with a toner storage container.
FIG. 3 is a cross-sectional view showing a state where the storage container mounting portion and the storage container are separated from each other, a partial enlarged cross-sectional view of the storage container, and a partial enlarged cross-sectional view of the storage container mounting portion.
FIG. 4 is a cross-sectional view of the toner replenishing device in a state where the storage container is mounted on the storage container mounting portion.
FIG. 5 is a partially enlarged cross-sectional view of a storage container and a storage container mounting portion.
6 is a cross-sectional view taken along line AA of the storage container and the storage container mounting portion in FIG.
[Explanation of symbols]
20 (Y, M, C, K) Developer (Developer)
30 (Y, M, C, K) Toner storage container (storage container)
31 Container body 311 Spiral protrusion (guide part)
312 Opening (toner discharge port)
32 Fixed lid 321 Abutting portion 322 Protruding portion 33 Container opening / closing lid 40 Toner replenishing device 41 (Y, M, C, K) Storage container mounting portion 412 Cover member 413 Retaining member 42 Outer cylinder member (toner guide means)
421 Rotating shaft 424 Toner transport passage 425 Toner replenishment port 43 Inner cylinder member (toner guide means)
431 opening (toner outlet)
432 Locking projection part 436 Paddle part (scraping part)
44 Mounting portion opening / closing lid 45 Coil spring 46 Storage container rotating gear 47 (Y, M, C, K) Toner storage portion (toner hopper)
473 Opening 48 Toner conveying part R Rotation center axis

Claims (3)

A toner storage container that discharges toner from an opening provided on the outer peripheral surface of the container body by rotating the toner stored in a cylindrical container body having a spiral protrusion inside, and the toner storage container is mounted. Toner guide means for guiding the inside of a toner transport passage having a paddle portion that receives, scrapes and pushes out toner from an opening provided at a position facing the opening of the toner container, and discharges the toner from a toner replenishing port; A toner storage section for receiving and storing the toner discharged from the toner supply port of the toner guide means, and rotating the mounted toner storage container to rotate the toner guide from the opening of the toner storage container. transported to the toner replenishing port by means to supply the toner to drop the toner to the toner reservoir through the toner supply opening of said toner guide means Toner supply device and butterflies. Claim 1, characterized in that the the opening of the toner container provided with a container lid for opening and closing the opening, provided with a mounting portion lid for opening and closing the opening the opening of the toner guiding means The toner replenishing device according to 1. The container opening / closing lid opens and closes the opening of the toner storage container, and the mounting portion opening / closing lid opens and closes the opening of the toner guiding means by the operation of attaching and detaching the toner storage container to and from the toner guiding means. The toner replenishing device according to claim 2.

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