JP3940559B2 - Toner storage container - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a toner storage container used in an image forming apparatus .
[0002]
[Prior art]
In conventional image forming apparatuses such as printers, copiers, and facsimile machines, a toner container such as a toner bottle or a cartridge is disposed in or near a unit having a developing device, and the toner container is directly or via a toner hopper. The developing device is replenished. In this case, the toner is transferred from the toner storage unit to the developing device using a mechanical auger means such as a screw or a paddle.
[0003]
However, when toner is transferred by the above-described mechanical auger means, the toner storage unit and the toner replenishing device must be installed at a position that is integral with or very close to the developing device because the screw can be arranged only in a substantially straight line. I didn't get it. This complicates the configuration of the toner replenishing device, hinders high cost, low productivity, and machine maintenance, makes it difficult to protect and maintain the toner quality characteristics, and allows the user to replace the toner container. There was also difficulty.
[0004]
A toner replenishing device that hardly causes such a problem is disclosed in Japanese Patent Laid-Open No. 4-9082, and in this toner replenishing device, toner is conveyed by the suction force of a suction means. Such an apparatus has an advantage that the toner can be replenished regardless of the positional relationship between the toner container and the developing device.
[0005]
[Problems to be solved by the invention]
However, it is generally known that toner used in an electrophotographic image forming apparatus has very poor fluidity and is difficult to transport. Therefore, the toner replenishing device has a problem that the toner is likely to be clogged with the tip of the suction pipe or in the middle of the suction pipe and the toner cannot be smoothly replenished.
[0006]
An object of the present invention is to provide a toner storage container for an image forming apparatus capable of greatly reducing the amount of remaining toner in view of the above-described conventional circumstances.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a toner storage container for an image forming apparatus that stores toner to be transferred to a developing device by a powder pump, wherein the toner storage container includes an outer box as a protective case, A toner bag made of a flexible sheet material housed in the box, and has an air supply path for supplying air into the toner bag and a toner supply path for sucking the toner in the toner bag . the toner discharge hole nozzle provided in the set of the image forming device is inserted is provided in the lower center, is formed into a shape that tapers toward the said toner discharge hole, wherein the toner bag On the upper surface opposite to the toner discharge hole, there is provided an opening as a deaeration part covered with a breathable filter that allows air to pass but does not allow toner to pass. When the nozzle is inserted, the nozzle is inserted into the toner discharge hole from the lower side in the vertical direction, and the air supplied from the lower side in the vertical direction through the nozzle passes through the stored toner layer and passes through the vent. A toner storage container is proposed in which the filter is removed from the toner filter to the outside of the toner bag .
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic view showing a color laser printer which is an example of an image forming apparatus provided with a toner replenishing device using a toner container of the present invention. This color laser printer has a configuration in which a paper feed unit 2 is disposed at the bottom of the apparatus main body 1 and an image forming unit 3 is disposed above the paper feed unit 2. The image forming unit 3 is provided with a transfer belt device arranged so as to be inclined so that the paper feed side is on the bottom and the paper discharge side is on the top. The transfer belt device has an endless transfer belt 20 wound around a plurality of belt wheels 22, in this example, four belt wheels 22, and the upper running side 21 of the transfer belt 20 has magenta ( Four image forming units 4M, 4C, 4Y, and 4Bk for M), cyan (C), yellow (Y), and black (Bk) are arranged in parallel.
[0019]
1 and 2, each of the image forming units 4M, 4C, 4Y, and 4Bk is provided with a photosensitive drum 5 as an image carrier, and the photosensitive drum 5 is rotated clockwise by a driving unit (not shown). Driven. Around the photosensitive drum 5, a charging roll 6 as a charging unit, an optical writing unit in which writing by laser light is performed by an optical writing unit 8, a developing unit 10 as a developing unit, and a cleaning unit 9 as a cleaning unit are provided. Yes. The developing device 10 is a two-component developing device composed of toner and a carrier, and the toner is replenished by a toner replenishing device, which will be described later, according to the amount of consumed toner.
[0020]
Next, an image forming operation for performing full color printing of the color printer shown in FIG. 1 will be described using the magenta image forming unit 4M.
The photosensitive drum 5 charged by the charging roll 6 is driven by an LD (laser diode) (not shown) to irradiate the polygon mirror 80 with laser light, and the reflected light is reflected through the cylinder lens or the like. Optical writing of an optical image to be developed with magenta toner is performed by the optical writing device 8 guided upward. By this writing, an electrostatic latent image is formed on the photosensitive drum 5 based on image data sent from a host machine such as a personal computer, and the latent image becomes a visible image of magenta toner by the developing device 10.
[0021]
On the other hand, a sheet designated as a transfer material is fed from the sheet feeding unit 2, and the fed sheet is once abutted against a registration roller 23 provided on the upstream side in the conveyance direction of the transfer belt 20. The sheet is fed onto the transfer belt 20 in synchronism with the visible image, and reaches the transfer position facing the photosensitive drum 5 by the running of the belt. At this transfer position, a visible image of magenta toner is transferred to the paper by the action of the transfer roll 24 disposed on the back side of the transfer belt 20.
[0022]
In the same manner as the above image forming operation, in the other image forming units 4C, 4Y, and 4Bk, visible images are formed by the respective toners on the surfaces of the respective photosensitive drums 5, and these visible images are conveyed by the transfer belt 20. Each time the sheet to be transferred arrives at each transfer position, the transfer is performed. Therefore, in this color printer, a full-color image is superimposed and transferred onto a sheet in a short time almost the same as that of monochrome. The transferred paper is separated from the transfer belt 20 and fixed by the fixing device 30. The sheet that has been fixed is normally discharged out of the machine as it is, or at this time, the sheet is reversed and discharged to the discharge tray 40 provided on the upper surface of the apparatus body 1 on the back side. Backside paper discharge is an almost indispensable condition for the printer to arrange prints in page order.
[0023]
Next, a toner replenishing device that replenishes toners stored in the toner containers 100M, 100C, 100Y, and 100Bk to the image forming units 4M, 4C, 4Y, and 4Bk will be described with reference to FIG. The toner replenishing devices that replenish the image forming units 4M, 4C, 4Y, and 4Bk have substantially the same structure.
[0024]
The developing device 10 is provided with a uniaxial eccentric screw pump that is a suction type powder pump 110 in the vicinity or integrally therewith. As shown in FIG. 2, the powder pump 110 is composed of a rotor 142 made of a screw having an eccentric shape made of a rigid material such as metal, and an elastic body such as rubber. And a holder 144 made of a resin material that encloses these and forms a powder conveyance path. The rotor 142 is rotationally driven via a gear 146 integrally connected to a drive shaft 145 connected by a pin joint. Reference numeral 147 denotes an electromagnetic clutch, and the operation of the powder pump 110 is controlled by the clutch.
[0025]
Further, a toner suction portion 148 is provided at the tip of the holder 144, that is, the right end in FIG. 2, and is connected to the toner suction portion 148 and a toner connection port 165 provided in a nozzle 160 described later by a toner transfer tube 149. ing. As the toner transfer tube 149, for example, a flexible tube having a diameter of 4 to 10 mm and made of a rubber material having excellent toner resistance (for example, polyurethane, nitrile, EPDM, silicon, etc.) is extremely used. An effective and flexible tube can be easily piped up and down, left and right. In the toner replenishing device configured as described above, the single-shaft eccentric screw pump, which is the powder pump 110, is capable of continuous quantitative transfer at a high solid-gas ratio, and is an accurate toner proportional to the rotational speed of the rotor 142. It is known that the transfer amount can be obtained. Therefore, when a toner replenishment command is issued by image density detection or the like, the powder pump 110 is operated, and the requested amount of toner is replenished to the developing device 10.
[0026]
On the other hand, the setting unit 200 provided in the image forming apparatus main body 1 in which the toner storage container 100 is set is configured as a separate unit from the developing device 10. The set unit 200 is provided with a nozzle 160 having a circular cross section inserted into the toner bag 102, and the toner container 100 is set to the set unit 200 of the image forming apparatus main body 1 from above. The nozzle 160 provided in the set unit 200 has a single tube structure, and a tip member 161 formed in a conical shape in cross section is provided on the upper part by integral molding or fixing, and air supply is provided following the tip member 161. A path 163 serving as a path and a toner supply path is provided. The inside of the nozzle 160 has a single tube structure, and the passage 163 is bent to the left in the drawing at the lower end of the nozzle 160 and is provided with a toner connection port 35 to which the toner transfer tube 149 is connected at the tip. Yes. The passage 163 is bent to the right in the figure above the toner connection port 165 and is provided with an air connection port 164.
[0027]
In the present embodiment, the air connection port 164 is connected to an air pump 151 as an air supply source in the air supply device via an air transfer pipe 152. When the air pump 151 is activated, air is ejected from the lower side into the toner storage container 100 through the air transfer pipe 152 and the air supply path 162. Then, the air blown into the toner storage container 100 flows through the toner layer while stirring the toner.
[0028]
The toner storage container 100 is configured as a back-in-box type having an outer box 101 as a protective case and a toner bag 102 as a flexible and deformable bag-like body detachably accommodated in the outer box 101. ing. The outer box 101 is made of a material such as paper, cardboard, or resin having rigidity, and has an internal space that can accommodate the toner bag 102 with almost no gap. Even if the toner bag 102 containing the toner is flexible, the toner storage container 100 is not only protected by being stored in the outer box 101, but is easy to handle because the handling is improved. The advantage is that it is easy to organize.
[0029]
Further, the bag portion of the toner bag 102 has a bag-like container shape with a single layer or multiple layers of a flexible sheet material (thickness of about 80 to 125 μm) such as a polyester film or a polyethylene film. The toner bag 102 is provided with a toner discharge hole 104 at the lower center thereof, and a base member 103 made of resin such as polyethylene or nylon is fixed. The toner discharge hole 104 of the base member 103 is provided with a single-layer or multi-layer seal 105 that functions as a self-closing valve, and the seal 105 is made of an elastic body made of a non-breathable foamed sponge or the like. Further, the toner bag 102 is formed in a shape that tapers toward the toner discharge hole 104 so that the toner hardly remains. Therefore, when the toner container 100 configured as described above is set in the setting unit 200, the nozzle 160 is inserted from the lower side in the vertical direction, that is, directly below.
[0030]
By the way, when the toner is sucked by the powder pump 3 in the image forming apparatus configured as described above, if the angle of the slope toward the bottom of the toner storage container 100 is small, the toner is less likely to fall near the nozzle 160 due to gravity, and the residual toner. become. Residual toner in the container can be easily sucked by supplying a large amount of air into the toner storage container 100 to sufficiently agitate and fluidize the toner. Can do. However, since the amount of air that can be supplied to the toner storage container 100 is limited to an amount corresponding to the volume, there is a possibility that the toner cannot be sufficiently stirred due to insufficient air.
[0031]
In this case, as shown in FIGS. 3A and 3B, in order to reduce the internal pressure in the toner storage container 100, an opening 106 is provided as a deaeration part, and air passes through the opening 106 but the toner. It is covered with a breathable filter 107 that does not pass through. The air-permeable filter 107 is provided on the upper surface on the side opposite to the seal 105 into which the nozzle 160 is inserted so that air that has sufficiently stirred the toner is removed.
[0032]
With this configuration, a part of the air supplied to the toner storage container 100 escapes from the air permeable filter 107 to the outside of the container, so that air can be supplied to the toner storage container 100 with almost no restriction. Therefore, since the toner in the toner storage container 100 is sufficiently agitated by a large amount of supplied air, the toner is more smoothly sucked by the powder pump 110, and the amount of toner remaining in the container can be greatly reduced. it can.
[0033]
As described above, when the air permeable filter 107 is provided in the toner container 100, a large amount of air can be supplied to the toner container 100. A large amount of air is supplied using an air pump 151. However, the full-color image forming apparatus includes four toner storage containers 100M, 100C, 100Y, and 100Bk. Therefore, four air supply apparatuses are provided. However, providing a plurality of air pumps 151 increases costs and requires installation space.
[0034]
Therefore, the present invention is configured as follows.
FIG. 4 is a schematic explanatory view showing an embodiment of the present invention.
In FIG. 4, toner storage containers 100M, 100C, 100Y, and 100Bk store yellow, magenta, cyan, and black toners having different colors, respectively. These toner storage containers 100 have a smaller number of installations, In this example, air is supplied by a single air pump 151. In this case, the air conveyance pipe 152 connected to the air pump 151 is provided with a fork part 153 that divides the supply path into four, and the four conveyance pipes 152M, 152C, 152Y, and 152Bk are respectively connected to the toner storage containers 100M, 100C, 100Y, and 100Bk. Are connected to nozzles 160M, 160C, 160Y, 160Bk inserted into The transfer pipes 152M, 152C, 152Y, and 152Bk are provided with on-off valves 154M, 154C, 154Y, and 154Bk that turn on and off the supply of air, respectively. The operation of the air pump 151 and the opening / closing of the on / off valves 154M, 154C, 154Y, 154Bk are controlled by a control unit (not shown).
[0035]
Since the color image forming apparatus configured as described above can supply air to them by the number of installed air pumps 151 that is smaller than the number of toner storage containers 100, space saving and low cost can be realized.
[0036]
FIG. 5 is a schematic explanatory view showing another embodiment of the present invention.
In FIG. 5, a surge tank 155 is provided between the air pump 151 and each of the toner storage containers 100M, 100C, 100Y, 100Bk as an air storage section that stores air. The surge tank 155 is provided with transport pipes 152M, 152C, 152Y, and 152Bk connected to the nozzles 160M, 160C, 160Y, and 160Bk inserted into the toner storage containers 100M, 100C, 100Y, and 100Bk. On-off valves 154M, 154C, 154Y, and 154Bk are provided at appropriate positions of the respective outlets of the surge tank 155 or the transfer pipes 152M, 152C, 152Y, and 152Bk.
[0037]
Even in such a configuration, it is possible to realize space saving and low cost of the apparatus as in the above embodiment.
In the embodiment shown in FIGS. 4 and 5, when the plurality of on-off valves 154M, 154C, 154Y, 154Bk are opened to supply air to the plurality of toner storage containers 100M, 100C, 100Y, 100Bk at the same time, the toner storage container. Variations occur in the amount of air supplied to 100M, 100C, 100Y, and 100Bk. That is, even if the two on-off valves 154 are turned on, the supply amount is reduced by a half by supplying more air to the weaker pressure such as a small amount of toner stored in the container. The air supply volume cannot be managed.
[0038]
Therefore, in the embodiment shown in FIG. 4, as shown in FIG. 6, the air pump 151 and the on / off valves 154M, 154C, 154Y, and 154Bk are synchronized with each other, and at the same time, a plurality of on / off valves are controlled not to be on. In the embodiment shown in FIG. 5, since the surge tank 155 is provided as shown in FIG. 7, it is not necessary to synchronize the air pump 151 and the on / off valves 154M, 154C, 154Y, 154Bk. Control so that multiple valves do not turn on.
[0039]
By controlling in this way, the amount of air supplied to the toner storage containers 100M, 100C, 100Y, and 100Bk can be easily grasped from the capability and operation time of the air pump 151, and the management can be easily performed.
[0040]
FIG. 8 is a schematic explanatory diagram illustrating a modification of the above-described embodiment.
In FIG. 8, the air conveyance pipe 152 connected to the air pump 151 is provided with a fork part 153 that divides the supply path into four, and the four conveyance pipes 152M, 152C, 152Y, and 152Bk are respectively connected to the toner storage containers 100M, 100C, The nozzles 160M, 160C, 160Y, and 160Bk inserted into 100Y and 100Bk are connected. The transfer pipes 152M, 152C, 152Y, and 152Bk have valve-operated surge tanks 155M, 155C, 155Y, and 155Bk that serve as air storage portions for storing air, and open / close valves as valve devices that turn on and off the supply of air. 154M, 154C, 154Y, and 154Bk are provided.
[0041]
Even in such a configuration, the space saving and low cost of the apparatus can be realized as in the above embodiment, and the surge tanks 155M, 155C, 155Y, and 155Bk with valves are individually provided, so that a plurality of toner storage containers can be simultaneously provided. Air can be supplied to 100. Further, since the toner in the toner container 100 is discharged by the air supply and the powder pump 151, there is almost no residual toner, and it is economical and the treatment of the toner container 100 after use can be performed safely and hygienically. .
[0042]
In the color printer shown in FIG. 1, the air supply to each of the toner storage containers 100M, 100C, 100Y, and 100Bk is controlled based on the flow shown in FIGS.
[0043]
In FIG. 9, the air supply to the toner storage containers 100M, 100C, 100Y, and 100Bk is performed when the toner is supplied to the developing device 10, but is performed when the number of repeats is an odd number in consideration of the air supply frequency. For this reason, first, it is determined whether the repeat number n is an odd number. Next, when the number of repeats is an odd number, it is determined whether the developing clutch (not shown) is turned on. When the developing clutch is turned on, it is determined whether the clutch 147 of the powder pump 110 is turned on. When the clutch 147 is turned on, toner is replenished to the developing device, and it is monitored whether the clutch 147 is turned off. At this time, since the air supply is performed independently, as shown in the flow of FIG. 10, one of the toner storage containers 100M, 100C, 100Y, and 100Bk is selected and the air supply is performed. During the air supply, when the clutch 147 is turned on or the air supply set time has elapsed, the air supply is terminated.
[0049]
【The invention's effect】
According to the configuration of the first aspect , even if air is supplied, an increase in internal pressure can be prevented, and the air stirs and fluidizes the toner, and the residual toner amount can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a color laser printer as an example of an image forming apparatus provided with a toner replenishing device using a toner container of the present invention.
FIG. 2 is a configuration diagram illustrating the toner replenishing device.
FIGS. 3A and 3B are a front view and a plan view of a toner storage container , respectively.
FIG. 4 is a schematic explanatory view showing an embodiment of the present invention.
FIG. 5 is a schematic explanatory view showing another embodiment of the present invention.
6 is a timing chart showing a control example of the embodiment of FIG.
FIG. 7 is a timing chart showing an example of control of the embodiment of FIG.
FIG. 8 is a schematic explanatory diagram showing a modification of the present invention.
FIG. 9 is a control flow chart relating to air supply of the color printer of FIG. 1;
10 is a flowchart showing a part of the details in the flowchart of FIG. 9; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Developing apparatus 100 Toner storage container 107 Breathable filter 140 Powder pump 149 Toner transfer tube 151 Air pump 152 Air conveyance pipe 154 Open / close valve 44, 44Y, 44M, 44C, 44K Surge tank

Claims (1)

In a toner storage container for an image forming apparatus that stores toner transferred to a developing device by a powder pump,
And the outer box as the toner container is protective case is composed of a toner bag made of flexible sheet material which is accommodated in the outer box, and an air supply path for supplying air to the toner bag, the toner bag A toner discharge hole for inserting a nozzle provided in a set portion of the image forming apparatus main body having a toner replenishment path for sucking the toner inside is provided in the lower center and directed toward the toner discharge hole. It is formed into a tapered shape,
The upper surface of the toner bag opposite to the toner discharge hole is provided with an opening as a deaeration part covered with a breathable filter that allows air to pass but does not allow toner to pass through.
When the set portion is set from above, the nozzle is inserted into the toner discharge hole from the lower side in the vertical direction,
A toner storage container, wherein air supplied from the lower side in the vertical direction through the nozzle passes through a stored toner layer and escapes from the air permeable filter to the outside of the toner bag .

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