JP2002278388A - Toner scatter preventing device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner scatter preventing device and an image forming device which can effectively prevent the inside and outside of the device from being stained with scattered toner. SOLUTION: This toner scatter preventing device is characterized in that an electromagnet member 3 which is close to the surface 101a of an image carrier 101 and can rotate reverse to the rotating direction of the image carrier and optionally control the magnetic field on its surface is arranged more downstream side in the rotating direction of the image carrier than a development area wherein magnetic toner 11 is supplied from a developing means 100 to the image carrier 101.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a toner scattering prevention device for preventing scattering of magnetic toner, and an image forming apparatus such as a copying machine, a facsimile, various printers, and a multifunction machine including the same.

[0002]

2. Description of the Related Art An image forming apparatus for developing a latent image formed on the surface of an image carrier using a magnetic toner as a developer is widely known. It is well known that in such an image forming apparatus, toner is scattered and the inside of the apparatus is dirty when a developing failure occurs or when the developing unit or the image carrier is replaced. As a technology to prevent toner scattering, mechanical and
Technologies that attempt to prevent this by an electrical method have already been proposed. For example, Japanese Patent Application Laid-Open No. 4-274263 discloses that
There has been proposed an apparatus which is provided with a tray for receiving toner dropped from an image carrier and moves toner in a direction away from the image carrier to prevent toner scattering generated on the image carrier. In addition,
JP-A-126261 proposes a device in which a toner guide plate is provided in an apparatus, and the material of the toner guide plate is hardly charged by friction, thereby suppressing toner adhesion and scattering.

[0003]

Problems to be solved by the present invention
In the method in which the scattered toner is collected at a specific location by an electric method, the area exerted by the dust collection mechanism is narrow, and the toner may be scattered by itself due to mechanical action. Effect is insufficient. In the dust collection method using the toner guide plate, if the airflow in the apparatus fluctuates due to a change in printing speed or the like, the fluctuation does not follow the fluctuation, and the toner dust collection is not always performed under optimum conditions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner scattering prevention apparatus and an image forming apparatus which can effectively prevent contamination inside and outside the apparatus due to scattering toner. Another object of the present invention is to provide an image forming apparatus capable of recycling scattered toner in addition to the above objects.

[0005]

According to a first aspect of the present invention, there is provided a toner scattering prevention device for preventing scattering of magnetic toner, wherein the toner scattering prevention device is disposed close to a surface of an image carrier and has a direction opposite to a rotation direction of the image carrier. And an electromagnet member capable of arbitrarily controlling the magnetic field on its surface. The scattered toner in the vicinity of the image carrier is attracted and held by the electromagnet member by magnetic force, and is rotated away from the surface of the image carrier by rotation of the electromagnet member.

According to a second aspect of the present invention, in the toner scattering prevention device of the first aspect, the electromagnet member carries the image bearing rather than the developing area for supplying the magnetic toner from the developing area material carrying the magnetic toner to the image carrier. It is characterized by being arranged on the downstream side in the rotation direction of the body. When the electromagnetically weak member is disposed downstream of the developing region in the rotation direction of the image carrier, the magnetic toner having poor development is attracted and held by the electromagnet member.

According to a third aspect of the present invention, in the toner scattering prevention device according to the second aspect, the magnetic field of the electromagnet member is weakened during a developing operation by the developing means, and increased during non-developing operations. It is characterized by having control means for controlling the applied current. Since the magnetic field of the electromagnet member is weakly controlled during the developing operation, the influence on the magnetic toner that normally adheres to the image carrier is reduced.

According to a fourth aspect of the present invention, there is provided the toner scattering prevention device according to the first, second or third aspect, wherein the toner dust is disposed below the electromagnet member and receives the magnetic toner adsorbed on the surface of the electromagnet member. It is characterized by having a portion. The magnetic toner adsorbed by the electromagnet member is collected in a toner collection unit.

According to a fifth aspect of the present invention, in the toner scattering prevention device of the fourth aspect, the toner dust collecting portion has a polarity opposite to a charging polarity of the magnetic toner. For this reason, the scattered toner is easily attracted to the toner collecting portion side.

The invention according to claim 6 is the invention according to claim 4 or 5.
The toner scattering prevention device according to the above aspect, characterized in that the electromagnet member and the toner dust collecting portion can be housed therein, and a substantially sealed case that exposes a part of the surface of the housed electromagnet member to the outside thereof. I have. The case prevents the scattered toner adsorbed by the electromagnet member or the scattered toner received by the toner dust collecting portion from re-scattering.

According to a seventh aspect of the present invention, in the toner scattering prevention device of the sixth aspect, an opening is formed in the case to make the internal pressure of the case substantially equal to the atmospheric pressure. Even when a pressure difference occurs between the inside of the case and the outside of the case, the inside of the case is set to approximately atmospheric pressure by the opening formed in the case, and the toner adsorbed by the electromagnet member is easily introduced into the case. Become.

According to an eighth aspect of the present invention, there is provided the toner scattering preventing device according to the sixth aspect, further comprising a piezoelectric element provided in contact with the toner dust collecting portion and vibrating the toner dust collecting portion. . When a voltage is applied to the piezoelectric element, the toner collecting portion vibrates, the toner received by the member is used, and the excess toner falls into the case, thereby suppressing a reduction in the dust collecting capability of the toner collecting portion itself.

According to a ninth aspect of the present invention, there is provided an image forming apparatus comprising the image carrier and developing means for supplying toner to the image carrier, and the toner scattering preventing device according to any one of the first to eighth aspects. It is characterized by: According to a tenth aspect of the present invention, there is provided an image forming apparatus including the image carrier, and a toner scattering preventing device according to any one of the fourth to eighth aspects, together with developing means for supplying a plurality of colors of toner to the image carrier. It is characterized by: The invention according to claim 11 is the invention according to claim 10
In the above-described image forming apparatus, the number of the toner dust collection units provided below the electromagnet member is provided corresponding to the color of the magnetic toner included in the developing unit. When there are a plurality of scattered toners, the toner of each color is collected in the corresponding toner collection unit.

According to a twelfth aspect of the present invention, in the image forming apparatus according to the eleventh aspect, the toner bottle containing the magnetic toner of each color and the scattered toner received by each color in each toner collecting unit are provided. Transport means for transporting the toner bottle to a corresponding color toner bottle. The toner collected for each color is conveyed to a toner bottle of a corresponding color by a conveying unit.

According to a thirteenth aspect of the present invention, in the image forming apparatus according to the twelfth aspect, the conveying means has an air pump, and a conveying pipe connecting the air pump, each toner bottle, and each toner dust collecting part. It is characterized by: The toner, which is a powder collected in the toner collecting unit for each color, is sent to each toner bottle in a state of being mixed with air via a transport pipe by the operation of an air pump.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a main configuration of the image forming apparatus. In FIG. 1, a developing unit 100 and a drum-shaped photoconductor 101 serving as an image carrier are provided around the photoconductor 101.
An endless intermediate transfer belt 103 as a transfer unit wound around a plurality of rollers is arranged. Photoconductor 1
Known components such as a charging device for charging the surface 101a of the photoreceptor 101, cleaning means for mainly removing residual toner on the surface 101a, and static elimination means for static elimination of the surface 101a are also provided around the photoreceptor 101. In the present embodiment, the photoconductor 101 is driven to rotate in a counterclockwise direction by a driving unit (not shown), and is irradiated with exposure light corresponding to image information on the upstream side of the developing unit 100, so that the surface of the photoconductor 101 is electrostatically latent. An image is formed. This electrostatic latent image is provided with developing means 10
0 (hereinafter referred to as “toner 1”).
Is supplied in the developing area where the developing roller 102 and the photoconductor 101 face each other by the rotation of the developing roller 102 as a developer carrier.

In the present embodiment, one-component toner 1 that acquires electric charge by frictional charging with the developing roller 102 or charge injection is used as a developer, and a thin toner layer is formed on the surface of the developing roller 102. This is brought close to the surface 101a on which an electrostatic latent image has been formed in advance, and the toner 1 is applied to the surface 101a.
a, and a developing method in which the toner is caused to fly on the photosensitive member 101.

A transfer charger 104 as first charge applying means for first-transferring the toner image formed on the surface 101a to the intermediate transfer belt 103 is located downstream of the developing area in the rotation direction of the photosensitive member 101. Intermediate transfer belt 10
3 are arranged inside. The toner image formed on the photoreceptor 101 is transferred to the intermediate transfer belt 103 at a primary transfer section formed between the intermediate transfer belt 103 and the front surface 101a, where a transfer charger 104 is disposed.

The intermediate transfer belt 103 rotates in a counterclockwise direction when one of a plurality of rollers around which the belt is wound is driven by a driving unit (not shown). A transfer sheet 1 serving as a recording material uses the toner image transferred to the intermediate transfer belt 103 at a portion substantially opposite to the transfer jar 104.
A transfer charger 114 as second charge applying means for transferring (secondary transfer) to the transfer belt 15 is disposed outside the intermediate transfer belt 103. The toner image transferred to the intermediate transfer belt 103 is transferred to the transfer charger 114 and the intermediate transfer belt 10.
The image is transferred to the transfer paper 115 at a secondary transfer portion which is a portion opposed to No. 3. The transfer paper 115 onto which the toner image has been transferred is conveyed to a fixing unit (not shown) and fixed, and is conveyed to a tray (not shown) or a post-processing device for bundling or sorting recording materials.

As shown in FIG. 2, the toner 1 supplied from the developing roller 102 to the photosensitive member 101
In this case, the electrostatic latent image formed on the image No. 01 is adhered by a Coulomba according to the charge. Some of the toner 1 has a surface 10 due to mechanical action or the like caused by contact with the photoreceptor 101.
In some cases, the toner particles 1 are separated from the toner particles 1a and become scattered toner 2, floating in the apparatus, and becoming one of the causes of contamination.

The toner scattering prevention device proposed in the present invention is:
This is to reduce the contamination inside the apparatus due to such scattered toner 2. Hereinafter, the configuration will be described by exemplifying some embodiments. In each embodiment, components having the same operation are denoted by the same reference numerals, and redundant description will be omitted.
Note that the toner 1 is indicated by a black circle and the scattered toner 2 is indicated by a white circle. (First Embodiment) As shown in FIG. 2, the toner scattering prevention device includes an electromagnet roller 3 as an electromagnet member. The electromagnet roller 3 is arranged closer to the surface 101a on the downstream side in the rotation direction of the photoconductor 101 than the developing area. That is, in FIG. 1, it is arranged near the surface 101a located between the developing roller 102 and the transfer charger 104. The electromagnet roller 3 is rotatably supported by a shaft (not shown), and is rotationally driven by a driving unit (not shown) in a direction opposite to the rotation direction of the photoconductor 101. The electromagnetic field of the electromagnet roller 3 can be arbitrarily controlled. That is, a power supply (not shown) is connected to the electromagnet roller 3. This power supply is capable of controlling on / off of a current to the ampere roller 3.

When the photosensitive member 101 and the developing roller 102 rotate to execute the developing operation, the photosensitive member 101 rotates from left to right in FIG.
The toner 1 supplied from the developing roller 102 adheres to the toner. Although the photoconductor 101 and the toner 1 are attracted to each other by Coulomba, a part of the scattered toner 2 generated due to transfer failure due to an impact due to mechanical contact between the developing roller 102 and the photoconductor 101 causes the rotation of the photoconductor 101. As a result, it is captured by the air boundary layer generated on the surface layer and floats in the device.

By arranging the electromagnet roller 3 rotating in the direction opposite to the rotation direction of the photosensitive member 101 close to the surface 101a, the scattered toner 2 is captured by the air boundary layer generated by the rotation of the electromagnet roller 3, While being separated from the air boundary layer on the surface 101 a, it is charged by the electromagnetic field of the electromagnet roller 3, attracted to and contacted by the electromagnet roller 3, and adheres to the surface of the electromagnet roller 3. It is desirable that the electromagnet roller 3 does not contact the surface 101a. This is to suppress the adverse effect of the vibration due to the rotation of the electromagnet roller 3 on the image formation.

The electromagnet roller 3 and the photoreceptor 101 are separated from each other by a fixed distance in the roller axis direction. Accordingly, a phenomenon in which the scattered toner 2 floats in the apparatus as the photoconductor 101 rotates can be suppressed. The effect of the electromagnet by the electromagnet roller 3 can be adjusted by arbitrarily turning on / off the power supplied to the electromagnet roller. That is, when the power is turned on, the roller becomes an electromagnet, so that the scattered toner 2 can be attracted to the surface of the electromagnet roller 3. When the power is turned off, the scattered toner 2 attached to the surface can be dropped by the effect of gravity, and it becomes easy to collect the scattered toner 2.

According to the configuration of this embodiment, the scattered toner 2
And the scattered toner 2 can be sent to another recycle process by an arbitrary toner collection method. (Second Embodiment) The toner scattering prevention device shown in FIG. 3 changes the magnetic force of the electromagnet roller 3 depending on the state of the image forming process of the image forming apparatus. That is, a control unit 4 for controlling the current applied to the electromagnet roller 3 is provided so that the magnetic field of the electromagnet roller 3 is weak during the developing operation by the developing unit 100 and becomes strong except during the developing operation. And the toner 1 used for development is intended to have as little influence as possible.

The electromagnet roller 3 has a core wound with a coil housed inside a cylindrical member, and the controller 4 changes the resistance of the coil. The control device 4 receives the information of the timing chart related to the image forming process of the image forming apparatus, and at the time when the toner for image formation is adhered on the photoreceptor 101 or during standby, that is, during the developing operation, The effect of the electromagnet is reduced, and the effect of the electromagnet is maximized at a timing when toner for image formation does not adhere to the photoreceptor 101, that is, except during the developing operation. As a result, it is possible to save energy in the electromagnet roller 3 and efficiently collect the scattered toner 2 while reducing the possibility of the influence of toner normally adhering on the photoconductor 101. (Third Embodiment) The toner scattering prevention device shown in FIG. 4 is configured such that, of the scattering toner 2 captured in the air boundary layer of the photoreceptor 101 below the electromagnet roller 3, the rotation of the electromagnet roller 3 The toner dust collecting unit 5 that receives the scattered toner 2 that has been separated and falls is arranged.
When the power to the electromagnet roller 3 is stopped or weakened in order to reduce or stop the effect of the electromagnet at the timing when the toner for image formation adheres to the photoreceptor 101 or during standby, the electromagnet roller 3 The captured scattered toner 2 that has adhered falls due to the effect of gravity. As in the present embodiment, the toner dust collecting section 5 is provided immediately below the electromagnet roller 3.
Is installed, the falling scattered toner 2 can be collected, and the scattered toner 2 captured when the developing device 100 is not operating can be collected by the toner collecting unit 5 when the developing device 100 is not operating.
Can be collected. Since the scattered toner 2 is received by the toner dust collection unit 5, the received scattered toner 2 can be easily reused. (Fourth Embodiment) The toner scattering prevention device shown in FIG. 5 has a case in which the electromagnet roller 3 and the toner dust collecting unit 5 can be housed and substantially sealed. The case 6 is provided with a roller window 6a at the upper part of the case so that a part of the surface of the electromagnet roller 3 is exposed to the outside. In FIG. 5, since the particle diameter of the toner 1 is exaggeratedly displayed, the gap between the window 6 a and the roller is also shown large, but the size of the window 6 a is attracted by the electromagnet roller 3. A gap can be formed between the electromagnet roller 3 and the scattered toner 2 to such an extent that the scattered toner 2 is carried into the case 6.

By providing such a case 6, of the scattered toner 2 captured from the photoreceptor 101 by the electromagnet roller 3 and the scattered toner 2 falling from the electromagnet roller 3, the scattered toner not captured by the toner collection unit 5 Toner 2 or scattered toner 2 overflowing from toner collection unit 5
Can be prevented, and the effect of preventing toner scattering can be further enhanced. (Fifth Embodiment) In the toner scattering prevention device shown in FIG. 6, an opening 7 is formed in a case 6 to make the case internal pressure substantially equal to the atmospheric pressure. The opening 7 is fine and is formed on the bottom surface of the case 7 in this embodiment, but may be formed on the side surface or the upper surface of the case 6.

When the opening 7 connecting the inside of the case and the outside of the case is formed in the case 6, the process speed of the apparatus is increased, and the rotation speed of the photosensitive member 101 is extremely increased, and the internal pressure of the case is increased. Even so, the pressure of the case 6 can be released, so that the scattered toner 2 adsorbed by the electromagnet roller 3 can be satisfactorily fed into the case 6. Thus, it is possible to avoid a problem that the scattered toner 2 adsorbed by the electromagnet roller 3 cannot be properly sent into the case 6 due to the internal pressure of the case. (Sixth Embodiment) The toner scattering prevention device shown in FIG. 7 is characterized in that the toner dust collecting section 5 has a polarity opposite to the charging polarity of the toner 1. The surface of the toner dust collecting portion 5 is charged positively, which is the polarity that the toner 1 is charged, in this case, the polarity opposite to the negative charge. As a result, the scattered toner 2 falling from the electromagnet roller 3
Is more easily attracted to the toner dust collector 5, and the scattered toner 2 can be more effectively received by the toner dust collector 5. For this reason, the scattered toner 2 captured while the developing device 100 is not operating is more efficiently collected by the toner collection unit 5 when the developing device 100 is not operating, and
Is also obtained. (Seventh Embodiment) The toner scattering prevention device shown in FIG. 8 is characterized in that it has a piezoelectric element 8 that vibrates the toner dust collecting section 5. In this embodiment, the piezoelectric element 8 is provided in contact with the lower surface of the toner dust collecting unit 5. The piezoelectric element 8 is configured to be able to selectively apply a toner dust collecting portion pulling vibration by appropriately applying a voltage from a control unit (not shown). By having such a piezoelectric element, it is possible to suppress a decrease in the toner scattering prevention effect due to excessive accumulation of the scattering toner 2 on the surface of the toner dust collecting unit 5, which is a problem that occurs when the toner scattering preventing device is operated for a long time. The effect that the effect can be maintained for a long time can be obtained. Needless to say, the toner collecting unit 5 shown in FIGS. 7 and 8 may be stored in the case 6 shown in FIGS. (Eighth Embodiment) FIG. 9 shows a schematic configuration of a color image forming apparatus having a developing device 105 as a developing means for supplying a plurality of color toners to the photoreceptor 101. Photoconductor 101
, The transfer charger 104 and the intermediate transfer belt 1
A toner scattering prevention device having the electromagnet roller 3 is arranged together with the toner dispersion device 03.

The developing device 105 includes a developing device 106 having yellow toner and a developing device 10 having cyan toner.
7. A well-known revolver developing method in which a developing device 108 having magenta toner and a developing device 109 having black toner are mounted on a revolver cartridge 150 which is a rotating body. When developing the electrostatic latent image formed for each color, the developing device 105 rotates the revolver cartridge 150 to position a developing device of a color corresponding to the electrostatic latent image in a portion facing the photoconductor 101. That is, the magnetic toner 1 of the corresponding color is supplied to the photoreceptor 101 for development.

When an image is formed using such a plurality of color toners, the amount of the scattered toner 2 is increased as compared with the case where an image is formed using a single color toner. For this reason, the electromagnet roller 3 is moved to the surface 101a on the downstream side in the rotation direction of the photoconductor 101 from the development area where each developing unit and the photoconductor are opposed.
, The scattered toner of each color can be absorbed and held, thereby preventing the inside of the apparatus from being stained due to the scattered toner. In order to further reduce the contamination due to the scattered toner 2 of each color, a form including the toner dust collecting unit 5 shown in FIG.

In the present embodiment, since the scattered toner has a plurality of colors, in order to collect the scattered toner for each color, a toner dust collecting portion corresponding to the color of the magnetic toner provided in the developing means is provided below the electromagnet roller 3. are doing. Reference numeral 51 denotes a yellow toner dust collector, 52 denotes a cyan toner dust collector, 53 denotes a magenta toner dust collector, and 54 denotes a black toner dust collector.
These toner dust collectors 51, 52, 53, and 54 are provided with a cartridge 50 that rotates in a revolver format, similarly to the developing device.
The cartridge 50 is removably attached to the cartridge, and its position is switched by rotating the cartridge 50. Specifically, the cartridge 50 is configured to be rotationally driven by a drive motor (not shown) in synchronization with the rotation of the revolver cartridge 150. When the developing device of a certain color is located in the developing area, the toner dust collecting portion of the color corresponding to the toner color of the developing device placed at the developing position is
The cartridge 50 is rotated so as to be located immediately below the cartridge 50. If the arrangement of the developing devices for each color and the arrangement of the toner dust collecting unit are opposed to each other, if the rotation angles of the revolver cartridge 150 and the cartridge 50 are respectively detected by a sensor or the like, it can be easily implemented.

As described above, the toner collecting units 51, 52, 53, and 54 corresponding to the colors of the toner are provided, and the toner collecting units 51, 52, 53, and 54 are used in the developing device used for development. By switching so as to be located below the electromagnet roller 3 according to the color, the scattered toner 2 can be collected for each color. (Ninth Embodiment) The scattered toner 2 adsorbed by the electromagnet roller 3 used in each embodiment hardly exerts a mechanical action, and has a short floating time in the air in the apparatus, and has a small There is almost no influence of the adhesion of dust, and the deterioration of the quality is extremely small as compared with residual toner caused by scraping off the surface of the photoconductor 101 by a cleaning blade (not shown). Therefore, recycling of the scattered toner 2 is easy.

Therefore, in the image forming apparatus according to this embodiment,
As shown in FIG. 10, the toner bottles 56, 57, 58, and 59 in which the magnetic toners of the respective colors are respectively stored, and the scattered toners received by the respective toner collecting units for the respective colors are stored in the toner bottles of the corresponding colors. It has a transporting means 55 for transporting.

As described above, the toner dust collecting sections 51, 52, 5
Toner bottles 56, 57, 58, 5 for supplying the scattered toner 2 captured by the toner cartridges 3, 54 to the toner developing devices of the respective colors
By transporting the scattered toner 2 to the hopper 9 or the like using the transporting means 55, the collected scattered toner 2 can be most reused (recycled).

The scattered toner 2 captured by the toner collecting units 51, 52, 53, 54 is transferred to the toner bottles 56, 57, 5
As the transporting means 55 for transporting the toner particles 8 and 59, it is also possible to transport the scattered toner 2 captured in the toner bottles of each color by mechanical means, for example, a screw method or a conveyor method. The quality of the toner deteriorates due to the thermal action due to friction with the system and the conveyor system, and the efficiency of the scattered toner that can be used for recycling decreases.

As shown in FIG. 11, an air pump 60 and an air pump 60
And conveying pipes 55A and 55B respectively connecting the toner bottles and the toner collecting sections. Transfer pipe 55
A connects, for example, the bottom of the yellow toner dust collection unit 51 to the suction port 61 of the air pump 60, and the transport pipe 55B connects the discharge port 62 of the air pump 60 and the supply unit of the toner bolt 57. In FIG. 11, the yellow toner dust collection unit 51
And the toner bottle 57 are connected by the transporting means 55, but the other toner collecting portions and the toner bolts are also connected in the same manner.

When the scattered toner 2 in each toner collecting portion is transported to each toner bottle by using the air pump 60 as described above, the scattered toner 2 is mixed with air and conveyed. The deterioration of toner quality due to physical action and thermal action is extremely small,
The reuse (recycling) rate can be increased.

[0038]

According to the first aspect of the invention, the scattered toner in the vicinity of the image carrier is attracted and held by the electromagnet member by magnetic force, and is rotated away from the surface of the image carrier by rotating the electromagnet member. In addition, the scattered toner can be reliably captured by simple means, and contamination of the inside of the apparatus by the scattered toner can be prevented.

According to the second aspect of the present invention, if the electromagnetically weak member is disposed downstream of the developing region in the rotation direction of the image carrier, the magnetic toner with poor development is attracted and held by the electromagnet member, so that the efficiency is improved. It is possible to capture the target scattered toner and prevent the device from being stained by the scattered toner.

According to the third aspect of the present invention, the magnetic field of the electromagnet member is weakly controlled during the developing operation, so that the effect on the toner normally adhering to the image bearing member is extremely reduced, and the efficiency is improved. The scattered toner can be captured, and contamination of the inside of the apparatus by the scattered toner can be prevented.

According to the fourth aspect of the present invention, even if the magnetic toner adsorbed by the electromagnet member falls from the member, the magnetic toner is received by the toner dust collecting portion, so that the dirt in the apparatus due to the scattered dropped toner is removed. Can be prevented, and the received scattered toner can be easily reused.

According to the fifth aspect of the present invention, since the toner collecting portion has a polarity opposite to the charging polarity of the magnetic toner, it becomes easy to attract and receive the scattered toner dropped from the electromagnet member, and the scattered toner is scattered. It is possible to more efficiently prevent the inside of the apparatus from being contaminated by toner.

According to the sixth aspect of the present invention, the case prevents the scattered toner adsorbed by the electromagnet member and the scattered toner received by the toner dust collecting portion from being re-scattered by the case. Dirt can be prevented more efficiently.

According to the seventh aspect of the present invention, even if a pressure difference occurs between the inside of the case and the inside of the case,
An opening formed in the case makes the inside of the case approximately atmospheric pressure, so that the scattered toner adsorbed by the electromagnet member is easily introduced into the case, and the contamination of the device by the scattered toner is more efficiently prevented. Can be.

According to the eighth aspect of the present invention, when the toner collecting portion is vibrated by the piezoelectric element, the toner received by the member is used in the toner collecting portion, and excess toner falls into the case to collect the toner. The reduction of the dust collecting performance of the dust part itself is suppressed, and the contamination of the inside of the apparatus by the scattered toner can be more efficiently prevented. According to the ninth and tenth aspects of the present invention, it is possible to more efficiently prevent the inside of the apparatus from being scattered by scattered toner.

According to the eleventh aspect of the present invention, when there are a plurality of scattered toners, the toners of each color are collected in the corresponding toner collection unit, so that the scattered toners can be easily reused. be able to. According to the twelfth aspect, the toner collected for each color is conveyed to the toner bottle of the corresponding color by the conveying means, so that the collected scattered toner can be reused. According to the thirteenth aspect of the present invention, the toner, which is the powder collected in the toner dust collecting unit for each color, is sent to each toner bolt in a state of being mixed with air via the transport pipe by the operation of the air pump. As compared with the screw system and the conveyor system, deterioration of toner quality due to physical action and thermal action is extremely small, and the reuse (recycling) rate can be increased.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating one embodiment of an image forming apparatus including a single color developing unit.

FIG. 2 is an enlarged view showing a first embodiment of a toner scattering prevention device.

FIG. 3 is an enlarged view showing a second embodiment of a toner scattering prevention device having a control unit.

FIG. 4 is an enlarged view showing a third embodiment of a toner scattering prevention device having a toner dust collecting unit.

FIG. 5 is an enlarged view showing a fourth embodiment of a toner scattering prevention device having a case.

FIG. 6 is an enlarged view showing a fifth embodiment of a toner scattering prevention device having an opening for releasing pressure in a case.

FIG. 7 is an enlarged view showing a sixth embodiment of a toner scattering prevention device in which a toner dust collecting unit is charged.

FIG. 8 is an enlarged view showing a seventh embodiment of a toner scattering prevention device having a piezoelectric element.

FIG. 9 is a schematic configuration diagram illustrating one embodiment of an image forming apparatus including a developing unit having a plurality of color toners and a toner scattering prevention device.

FIG. 10 is a schematic diagram illustrating a form in which a toner dust collecting unit and a toner bolt are connected by a conveying unit.

FIG. 11 is a schematic configuration diagram illustrating one embodiment of a transport unit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 magnetic toner 2 scattered toner 3 electromagnet member 4 control device 5 toner dust collection unit 6 case 7 opening 8 piezoelectric element 50 dust collection member 51 yellow scattered toner dust collection unit 52 cyan scattered toner dust collection unit 53 magenta scattered toner dust collection unit 54 Black scattered toner dust collecting section 55 Conveying means 56 Yellow toner bottle 57 Cyan toner bottle 58 Magenta toner bottle 59 Black toner bottle 60 Air pump

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H027 ED08 ED27 EF09 JA01 JB09 JC01 2H030 AD03 AD17 BB24 BB42 2H071 CA01 CA05 DA08 DA09 EA04 EA10 EA18 2H077 AC16 BA10 CA15 CA16 EA03 EA12 EA13 J0211H01 GA01 GB02 KB11 KB12 KC00 KG08 KH07 KH17 KJ02

Claims (13)

[Claims] 1. An apparatus for preventing scattering of magnetic toner, which is disposed close to the surface of an image carrier, rotates in a direction opposite to the rotation direction of the image carrier, and can arbitrarily control a magnetic field on the surface. A toner scattering prevention device comprising an electromagnet member. 2. The toner scattering prevention device according to claim 1, wherein the electromagnet member is disposed on a downstream side in a rotation direction of the image carrier from a developing area for supplying magnetic toner from a developing unit to the image carrier. A toner scattering prevention device characterized by the above-mentioned. 3. The toner scattering prevention device according to claim 2, wherein the magnetic field of the electromagnet member is applied to the electromagnet member such that the magnetic field is weak during a developing operation by the developing unit and strong during other than the developing operation. A toner scattering prevention device comprising a control unit for controlling a current. 4. The toner scattering prevention device according to claim 1, further comprising: a toner dust collecting portion disposed below the electromagnet member and receiving the magnetic toner adsorbed on the surface of the electromagnet member. A toner scattering prevention device characterized by the above-mentioned. 5. The toner scattering prevention device according to claim 4, wherein the toner dust collection portion has a polarity opposite to a charging polarity of the magnetic toner. 6. The toner scattering prevention device according to claim 4, wherein the electromagnet member and the toner dust collecting portion can be housed therein, and a part of the surface of the housed electromagnet member is exposed to the outside. A toner scattering prevention device having a sealed case. 7. The toner scattering prevention device according to claim 6, wherein an opening is formed in the case to make the case internal pressure equal to the atmospheric pressure. 8. The toner scattering prevention device according to claim 6, further comprising a piezoelectric element provided in contact with said toner collection unit and vibrating said toner collection unit. 9. An image forming apparatus having an image carrier and developing means for supplying toner to the image carrier, comprising: the toner scattering preventing device according to claim 1. Characteristic image forming apparatus. 10. An image forming apparatus having an image carrier and a developing unit for supplying a plurality of colors of toner to the image carrier, comprising the toner scattering preventing device according to claim 4. An image forming apparatus. 11. The image forming apparatus according to claim 10, wherein the number of toner dust collecting units provided below the electromagnet member is provided corresponding to the color of the magnetic toner provided in the developing unit. Toner scattering prevention device. 12. The image forming apparatus according to claim 11, wherein the toner bottles containing the magnetic toners of the respective colors, and the scattered toners received by the respective toner collecting units for the respective colors are transferred to the toner bottles of the corresponding colors. An image forming apparatus comprising: 13. An image forming apparatus according to claim 12, wherein said conveying means has an air pump, and a conveying pipe for connecting said air pump, each toner bottle and each toner collecting section. Image forming device.