JP6945789B2 - Develop equipment and image forming equipment - Google Patents

Description

The present invention relates to a developing device and an image forming device.

A developing device that develops an electrostatic latent image on an image holder with a developing container that houses a developing agent containing toner and a developing roll that carries the developing agent by rotation, and an image derived from the toner image formed by the development. An image forming apparatus for forming an image on paper is widely known.

Here, it is known that the rotation of the developing roll causes an air flow to increase the air pressure in the developing apparatus. When the process speed is increased to improve the productivity of the image, the increase in the air pressure in the developing apparatus becomes remarkable. Then, due to this increase in air pressure, air flows out from the gap between the developing container and the developing roll and the slight gap between the members constituting the developing container, and at the same time, the toner flows out and pollutes the surroundings. There is a risk of

In order to suppress the occurrence of this problem, it has been proposed to provide a filter for preventing the outflow of toner by providing a pressure relief port for venting air in the developing container.

For example, Patent Document 1 proposes improving the convenience of replacement work of a filter in a configuration in which a pressure relief slit is provided in the developing apparatus and a filter is provided at the tip of the slit.

Further, Patent Document 2 proposes to apply vibration to a frame including a filter in order to prevent clogging of the filter with respect to a toner recovery device rather than a developing device.

Japanese Unexamined Patent Publication No. 2005-352076 Japanese Unexamined Patent Publication No. 2014-228825

In the toner recovery device disclosed in Patent Document 2 described above, the life of the filter is extended by vibrating the frame and vibrating the filter to shake off the toner. However, when this is applied to a developing device, the developing device plays a role of developing an electrostatic latent image, and therefore, when the frame is vibrated, the vibration may cause deterioration of image quality, and therefore development. Vibration can be generated only at a timing other than the timing at which the above is performed, which is a major restriction.

The present invention provides a developing device and an image forming device capable of scraping off toner adhering to a filter by a method that is less likely to lead to deterioration of image quality due to vibration as compared with the case of vibrating a frame. The purpose.

Claim 1 is
A developing container in which pressure relief passages opened on both the inside and the outside are formed to store a developer containing toner, and a developing container.
An electrostatic latent image is formed, developed with toner, and placed adjacent to an image holder that holds the toner image. While rotating, the developer in the developing container is held on the surface and faces the image holder. A developing roll that carries the image-retaining body to the developed area, develops the electrostatic latent image of the image-retaining body with the toner in the developing agent, and causes the image-retaining body to hold the toner image.
A filter having a roll shape and rotating at a predetermined time, which is arranged at a position facing an opening opened on the outside of the pressure relief passage and adheres toner in an air flow flowing out from the opening to the surface. Prepare,
The developing container has a scraping portion that comes into contact with the filter and scrapes off the toner adhering to the filter as the filter rotates.
The opening opened inside the depressurization passage is an opening that opens downward from the horizontal, and is erected in the depressurization passage from the opening opened inside, and the depressurization is performed from the opening opened inside. have a wall portion that passes to the downstream side by circuitous air flowing into the passage, further
Between the inwardly open opening and the outwardly open passage, a plurality of erections are erected from the lower surface of the depressurization passage to form a passage through which air passes in the upper part of the depressurization passage. A plurality of hanging walls, which are provided one by one between the wall and the adjacent standing walls, and which form a passage for passing air by hanging from the upper surface of the pressure relief passage at the lower part in the pressure relief passage. a developing device characterized in that it have a.

2. The developing apparatus according to claim 1, wherein the developing container has a scraped toner accommodating portion for accommodating toner scraped from the filter by the scraping portion.

Claim 3
An image retainer in which an electrostatic latent image is formed and developed with toner to hold the toner image,
It is provided with a developing device that develops an electrostatic latent image on the image holder with toner and causes the image holder to hold the toner image, and forms an image derived from the toner image on the image holder on paper. It is an image forming device
The developing device
A developing container in which pressure relief passages opened on both the inside and the outside are formed to store a developer containing toner, and a developing container.
It is arranged at a position adjacent to the image holder, and while rotating, the developer in the developing container is held on the surface and carried to the developing region facing the image holder, and the electrostatic latent image of the image holder is displayed. A developing roll developed with the toner in the developer and
A filter having a roll shape and rotating at a predetermined time, which is arranged at a position facing an opening opened on the outside of the pressure relief passage and adheres toner in an air flow flowing out from the opening to the surface. Prepare,
The developing container has a scraping portion that comes into contact with the filter and scrapes off the toner adhering to the filter as the filter rotates.
The opening opened inside the depressurization passage is an opening that opens downward from the horizontal, and is erected in the depressurization passage from the opening opened inside, and the depressurization is performed from the opening opened inside. have a wall portion that passes to the downstream side by circuitous air flowing into the passage, further
Between the inwardly open opening and the outwardly open passage, a plurality of erections are erected from the lower surface of the depressurization passage to form a passage through which air passes in the upper part of the depressurization passage. A plurality of hanging walls, which are provided one by one between the wall and the adjacent standing walls, and which form a passage for passing air by hanging from the upper surface of the pressure relief passage at the lower part in the pressure relief passage. an image forming apparatus, characterized by have a.

The developing apparatus according to claim 1 and the image forming apparatus according to claim 3 have a structure in which the filter is rotated to scrape off the toner, which may lead to deterioration of image quality due to vibration as compared with the case where the frame is vibrated. The toner adhering to the filter can be scraped off with a small method.
Further, according to the developing apparatus of claim 1 and the image forming apparatus of claim 3 , by having the above-mentioned standing wall and hanging wall , the amount of toner arriving at the filter is reduced, and the life of the filter is extended. Connect.

According to the developing apparatus of claim 2, since the scraped toner accommodating portion is provided, the scraped toner is returned to the developing agent in the developing container as compared with the structure in which the scraped toner is returned to the developing agent through the returning path. Toner is prevented from adhering to the filter, which leads to a longer life of the filter.

According to the developing apparatus of claim 3, the meandering path of the pressure relief passage reduces the amount of toner that reaches the filter, leading to a longer life of the filter.

It is a block diagram which shows one Embodiment of the image forming apparatus of this invention. It is a schematic diagram which showed the internal structure of the developing apparatus.

Hereinafter, embodiments of the present invention will be described.

FIG. 1 is a configuration diagram showing an embodiment of the image forming apparatus of the present invention.

In the image forming apparatus 1 shown in FIG. 1, image forming portions 10Y, 10M, 10C, and 10K corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K) are arranged in parallel. It is a tandem type color printer that can print a single color image and can also print a full color image consisting of a four-color toner image.

The image forming apparatus 1 includes an exposure device 20 that irradiates exposure light to each of the image forming portions 10Y, 10M, 10C, and 10K, and an intermediate transfer in which a toner image is transferred from the image forming portions 10Y, 10M, 10C, and 10K of each color. The belt 30, the secondary transfer device 50 that transfers the toner image from the intermediate transfer belt 30 to the paper, the fixing device 60 that fixes the toner to the paper, the belt cleaner 70 that collects the toner from the intermediate transfer belt 30, and the paper. It includes a paper transport device 80 for transporting and a paper container C for accommodating the paper P. Further, the image forming apparatus 1 contains the toners of the toner containers 18Y, 18M, 18C, 18K for accommodating the toners of each color of YMCK and the toners of the toner containers 18Y, 18M, 18C, 18K. Toner supply devices 19Y, 19M, 19C, and 19K that supply 10K, respectively, are also provided.

Since the four image forming portions 10Y, 10M, 10C, and 10K have substantially the same configurations, the image forming portion 10Y corresponding to yellow will be described here as a representative. The image forming unit 10Y includes a photoconductor 11Y, a charger 12Y, a developing device 14Y, a primary transfer device 15Y, and a photoconductor cleaner 16Y. The photoconductor 11Y has a cylindrical surface, holds an image formed on the surface, and rotates in the direction of arrow a around the axis of the cylinder. The photoconductor 11Y corresponds to an example of an image holder according to the present invention. The same applies to the other photoconductors 11M, 11C and 11K. Further, the developing device 14Y corresponds to an example of the developing device of the present invention and an example of the developing device in the image forming device of the present invention. The same applies to the other developing devices 14M, 14C, 14K.

The charger 12Y has a charging roll that rotates while in contact with the photoconductor 11Y, and charges the surface of the photoconductor 11Y.

A developer containing toner and a magnetic carrier is housed in the developing apparatus 14Y. The developing apparatus 14Y includes a developing roll 142, and the developing roll 142 conveys the developer to the photoconductor 11Y. When the toner of the developing agent adheres to the photoconductor 11Y, a toner image is formed on the photoconductor 11Y. The toner container 18Y and the toner supply device 19Y replenish the developing device 14Y with new toner. A toner transfer mechanism driven by the control of the control unit 1B is provided in the toner supply device 19Y.
The primary transfer device 15Y transfers the toner image to the intermediate transfer belt 30. The photoconductor cleaner 16Y cleans the surface of the photoconductor 11Y after transfer.

The exposure device 20 emits exposure light based on an image signal supplied from the outside, and exposes the photoconductors 11Y, 11M, 11C, and 11K with the emitted light.

The intermediate transfer belt 30 is an endless band-shaped member supported by the belt support rolls 31, 32, 33, 34, and the arrow b passes through the image forming portions 10Y, 10M, 10C, 10K, and the secondary transfer device 50. Orbit in the direction shown in. The intermediate transfer belt 30 holds a toner image of each color formed by the image forming portions 10Y, 10M, 10C, and 10K.

The secondary transfer device 50 is a roll that rotates with the intermediate transfer belt 30 and the paper sandwiched between the backup roll 34, which is one of the belt support rolls 31 to 34. A voltage that generates an electric field for transferring toner is supplied between the secondary transfer device 50 and the backup roll 34, and the toner image on the intermediate transfer belt 30 is transferred onto the paper.
The belt cleaner 70 brings the blade into contact with the intermediate transfer belt 30 to remove the toner on the intermediate transfer belt 30.
The fixing device 60 includes a heating roll 61 and a pressure roll 62, and fixes the toner image on the paper by passing the paper on which the toner image before fixing is formed.

The paper transport device 80 takes out the paper P from the paper container C and transports it along the paper transport path r via the secondary transfer device 50 and the fixing device 60. The paper transport device 80 includes a pickup roll 81 for taking out the paper P stored in the paper container C, a handling roll 82 for handling the taken out paper P, a transport roll 83 for transporting the paper P, and a secondary transfer device 50 for the paper P. It is provided with a registration roll 84 for transporting the paper P to the outside, a discharge roll 86 for discharging the paper P to the outside, and reverse transport rolls 88 and 89 for transporting the paper P during double-sided printing.

The basic operation of the image forming apparatus 1 shown in FIG. 1 will be described. In the yellow image forming portion 10Y, the photoconductor 11Y is rotationally driven in the direction of the arrow a, and the surface of the photoconductor 11Y is charged by the charger 12Y. This also applies to the image forming portions 10M, 10C, and 10K corresponding to colors other than yellow. The exposure device 20 irradiates the photoconductors 11Y, 11M, 11C, and 11K with exposure light corresponding to the data corresponding to each color in the image signal. Yellow (Y) will be described as a representative. The exposure device 20 forms an electrostatic latent image on the surface of the photoconductor 11Y by irradiating the surface of the photoconductor 11Y with exposure light based on the image signal corresponding to yellow among the image signals supplied from the outside. .. The developing apparatus 14Y forms a toner image by developing the electrostatic latent image with yellow toner. Toner is supplied to the developing device 14Y from the toner container 18Y by the toner supply device 19Y. The photoconductor 11Y rotates while holding a yellow toner image formed on the surface. The toner image formed on the surface of the photoconductor 11Y is transferred to the intermediate transfer belt 30 by the primary transfer device 15Y that applies a transfer potential between the surface of the photoconductor 11Y and the intermediate transfer belt 30. After the transfer, the toner remaining on the photoconductor 11Y is collected and removed by the photoconductor cleaner 16Y.

The intermediate transfer belt 30 is supported by the support rolls 31 to 34 and circulates in the direction of arrow b, and the image forming portions 10M, 10C, and 10K corresponding to colors other than yellow are similar to the image forming portions 10Y. A toner image corresponding to each color is formed, and the toner image of each color is transferred onto the intermediate transfer belt 30 by superimposing the toner image transferred by the image forming unit 10Y. On the other hand, the paper P in the paper container C is taken out by the pickup roll 81, and is conveyed by the handling roll 82, the transfer roll 83, and the registration roll 84 in the direction of the arrow c toward the secondary transfer device 50. Will be done. The paper P is fed to the secondary transfer device 50 at the timing when the toner image is transferred onto the intermediate transfer belt 30 by the registration roll 84. The secondary transfer device 50 transfers the toner image of the intermediate transfer belt 30 to the paper P by applying a transfer bias potential between the intermediate transfer belt 30 and the paper P. The paper P on which the toner image is transferred is conveyed to the fixing device 60 by the secondary transfer device 50, and the toner image transferred on the paper P is fixed. In this way, an image is formed on the paper P. The paper P on which the image is formed is ejected to the upper part of the image forming apparatus 1 by the ejection roll 86. The toner remaining on the intermediate transfer belt 30 after transfer by the secondary transfer device 50 is removed by the belt cleaner 70.

In the case of double-sided printing in which an image is formed on the back surface of the surface on which the image is formed, the ejection roll 86 ejects the paper P halfway from the ejection port and then conveys the paper P in the reverse direction. The paper P conveyed in the opposite direction is conveyed by the reverse transfer rolls 88 and 89 via the reverse transfer path r'. The conveyed paper P is sent from the registration roll 84 to the secondary transfer device 50 in a state of being turned upside down, and an image is also formed on the back surface.

FIG. 2 is a schematic view showing the internal configuration of the developing apparatus.

The image forming apparatus 1 shown in FIG. 1 is provided with four developing apparatus 14Y, 14M, 14C, and 14K, all of which have substantially the same configuration. Therefore, in the description after FIG. 2, the reference numerals Y, M, C, and K representing the color of the toner are removed, and the term "developing apparatus 14" is simply referred to. The same applies to each component of the developing device 14. The same applies to the components other than the developing device 14 as described with reference to FIG.

The developing apparatus 14 includes a developing container 141 containing a developing agent (not shown) containing toner inside, and a developing roll 142 in which a part of the developing container 141 is exposed. In the developing container 141, two augers 143 and 144 arranged in parallel with each other and extending in the longitudinal direction of the developing container 141 are arranged. These augers 143 and 144 are members that reciprocate in the longitudinal direction while stirring the developer in the developing container 141 by rotation.

Further, the developing roll 142 is arranged at a position adjacent to the photoconductor 11, and while rotating in the direction of arrow e, the developing agent in the developing container 141 is held on the surface of the developing area d facing the photoconductor 11. It is carried and the electrostatic latent image on the photoconductor 11 is developed with the toner in the developing agent. By this development, a toner image is formed on the photoconductor 11. Subsequent handling of the toner image formed on the photoconductor 11 is as described with reference to FIG.

Further, the developing container 141 is formed with pressure relief passages 145 opened inside and outside the developing container 141. Further, in the developing apparatus 13, a filter 146 is arranged at a position of the pressure relief passage 145 facing the opening 145a opened to the outside. The filter 146 is a filter that adsorbs the toner in the air flow flowing out from the opening 145a to the surface. The pressure relief passage 145 is a slit-shaped passage extending in the longitudinal direction of the developing container 141, and the filter 146 also extends in that direction and rotates together with the developing roll 142 and the augers 143 and 44. The filter 146 may be constantly rotated, but may be provided with a structure for switching between rotation and stop so that the filter 146 rotates only at a predetermined time.

When the air pressure in the developing container 141 increases, air flows into the depressurizing passage 145 from the opening 145b opened inside the developing container 141 in the depressurizing passage 145. This air contains floating toner. The air flowing into the depressurization passage 145 is captured by the filter 146 arranged facing the outward opening 145a.

Here, the developing container 141 further has a cleaning edge 147 located in the pressure relief passage 145. The cleaning edge 147 extends linearly in its longitudinal direction and is in contact with the filter 146. When the filter 146 rotates, the toner captured by the filter 146 and adhering to the filter 146 is scraped off from the filter 146 by the cleaning edge 147. As a result, the filter 145 is cleaned, and the life of the filter 146 is extended until the life of the developing device 14 is exhausted in the present embodiment. The cleaning edge 147 corresponds to an example of a scraped portion according to the present invention.

Below the cleaning edge 147, a scraped-off toner accommodating portion 148 isolated from the developing agent in the developing container 141 is provided. The toner scraped from the filter 146 is stored in the scraped toner accommodating portion 148 until the life of the developing device 14 is exhausted.

If the bottom of the scraped toner accommodating portion 148 is open and the passage where the scraped toner falls from the filter 146 and is mixed again with the developer in the developing container 141 is opened, the passage is passed through the passage. An rising air flow is generated, and the toner may adhere to the filter on the air flow. In the present embodiment, since the scraped-off toner accommodating portion 148 whose bottom is closed is provided, the generation of the rising air flow is prevented, and from this point as well, the life of the filter 146 is extended. There is.

Further, in the pressure relief passage 145, a plurality of ribs 145c that alternately repeat standing from the floor and hanging from the ceiling are provided, and these ribs 145c meander in the pressure relief passage 145. A meandering path through which air flows is formed. The flow of the air flowing in the pressure relief passage 145 is weakened by this meandering, and most of the toner that has flowed into the pressure relief passage 145 along with the air flow is adsorbed by those ribs 145c and reaches the filter 146. The amount of toner used is reduced. Therefore, in the case of the present embodiment, the life of the filter 146 is extended from this point as well.

Further, in the case of the present embodiment, a wall portion 149 erected in the depressurization passage 145 is provided at a position adjacent to the opening 145b opened inside the developing container 141 of the depressurization passage 145. .. Due to the presence of the wall portion 149, the air flowing into the pressure relief passage 145 from the opening 145b opened inside thereof detours in the vertical direction and then flows to the downstream side. Therefore, most of the toner mixed in the air flowing into the pressure relief passage 145 is blocked by the wall portion 149 and falls without advancing to the downstream side, and the presence of the wall portion 149 also causes a filter. The amount of toner reaching 146 is reduced.

Further, the filter 146 shown in FIG. 2 has a shape in which a small-diameter sponge is spirally wound around a rod-shaped axis. Having such a spiral shape increases the surface area and improves the efficiency of capturing toner in the air flow. The thickness and pitch of the spiral of the filter 146, the size of the gap between the outward opening 145a of the depressurization passage 145 and the filter 146, and the like depend on the air permeability of the air flow passing therethrough and the filter 146. It is determined by the balance with the toner recovery performance.

The filter 146 does not have to have a spiral shape as shown in FIG. For example, the filter 146 may be a sponge with a simple roll-shaped surface. A filter made of a sponge having a simple roll-shaped surface can be manufactured at a lower manufacturing cost than a spiral-shaped sponge. Even if the filter is made of a sponge having a simple roll-shaped surface, if the toner recovery performance in the air flow is sufficient, this simple-shaped filter may be adopted. Even in the case of this simple roll-shaped sponge, the diameter, the size of the gap between the sponge and the opening 145a, etc. are determined by the balance between the air permeability of the air flow passing through the sponge and the toner recovery performance by the filter. NS.

Further, the filter 146 does not have to be a sponge, and may be, for example, a brush having a shape in which a large number of rod-shaped protrusions (brush bristles) protrude radially from a long axial center. The arrangement of the protrusions (brush bristles) of the brush may also be arranged linearly in the axial direction, for example, or may be arranged so as to draw a spiral. Such a brush can also be used as the filter 146. When the brush is adopted as a filter, the cleaning edge 147 may have a mountain wave shape (jagged shape) in the longitudinal direction instead of a member extending linearly in the longitudinal direction. The mountain wave shape (jagged shape) can improve the cleaning performance.

Here, an example in which the present invention is applied to the developing apparatus 14 incorporated in the so-called tandem image forming apparatus 1 shown in FIG. 1 has been described, but the present invention describes the type of image forming shown in FIG. The device is not limited to the device, and may be, for example, a monochrome printer or the like, and can be applied to various types of image forming devices.

1 Image forming device 10 Image forming unit 11 Photosensitive material 14 Developing device 141 Developing container 142 Development roll 143, 144 Auger 145 Depressurizing passage 145a Opening outside 145b Opening inside 145c Rib 146 Filter 147 Cleaning edge 148 Scraping Toner housing 149 wall

Claims (3)

A developing container in which pressure relief passages opened on both the inside and the outside are formed to store a developer containing toner, and a developing container.
An electrostatic latent image is formed, developed with toner, and placed adjacent to an image holder that holds the toner image. While rotating, the developer in the developing container is held on the surface and faces the image holder. A developing roll that carries the image-retaining body to the developed area, develops the electrostatic latent image of the image-retaining body with the toner in the developing agent, and causes the image-retaining body to hold the toner image.
A filter having a roll shape and rotating at a predetermined time, which is arranged at a position facing an opening opened on the outside of the pressure relief passage and adheres toner in an air flow flowing out from the opening to the surface. Prepare,
The developing container has a scraping portion that comes into contact with the filter and scrapes off the toner adhering to the filter as the filter rotates.
The opening opened inside the depressurization passage is an opening that opens downward from the horizontal, and is erected in the depressurization passage from the opening opened inside, and the depressurization is performed from the opening opened inside. have a wall portion that passes to the downstream side by circuitous air flowing into the passage, further
Between the inwardly open opening and the outwardly open passage, a plurality of erections are erected from the lower surface of the depressurization passage to form a passage through which air passes in the upper part of the depressurization passage. A plurality of hanging walls, which are provided one by one between the wall and the adjacent standing walls, and which form a passage for passing air by hanging from the upper surface of the pressure relief passage at the lower part in the pressure relief passage. a developing device which is characterized in that have a. The developing apparatus according to claim 1, wherein the developing container has a scraped toner accommodating portion for accommodating toner scraped from the filter by the scraping portion. An image retainer in which an electrostatic latent image is formed and developed with toner to hold the toner image,
It is provided with a developing device that develops an electrostatic latent image on the image holder with toner and causes the image holder to hold the toner image, and forms an image derived from the toner image on the image holder on paper. It is an image forming device
The developing device
A developing container in which pressure relief passages opened on both the inside and the outside are formed to store a developer containing toner, and a developing container.
It is arranged at a position adjacent to the image holder, and while rotating, the developer in the developing container is held on the surface and carried to the developing region facing the image holder, and the electrostatic latent image of the image holder is displayed. A developing roll developed with the toner in the developer and
A filter having a roll shape and rotating at a predetermined time, which is arranged at a position facing an opening opened on the outside of the pressure relief passage and adheres toner in an air flow flowing out from the opening to the surface. Prepare,
The developing container has a scraping portion that comes into contact with the filter and scrapes off the toner adhering to the filter as the filter rotates.
The opening opened inside the depressurization passage is an opening that opens downward from the horizontal, and is erected in the depressurization passage from the opening opened inside, and the depressurization is performed from the opening opened inside. It has a wall part that allows the air that has flowed into the passage to detour and pass to the downstream side, and further
Between the inwardly open opening and the outwardly open passage, a plurality of erections are erected from the lower surface of the depressurization passage to form a passage through which air passes in the upper part of the depressurization passage. A plurality of hanging walls, which are provided one by one between the wall and the adjacent standing walls, and which form a passage for passing air by hanging from the upper surface of the pressure relief passage at the lower part in the pressure relief passage. an image forming apparatus characterized by have a.

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