JPH09222833A - Separating device and electrophotographic image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a stay of magnetic power such as a magnetic developer from staying in a separating device when meshes of a filter are clogged by detecting a change in a load applied to a filter vibration imparting means, and retreating a second magnetic force generating means. SOLUTION: When a filter 13 is damaged, even if a cam 24 rotates, vibration is not transmitted to the filter 13, and it becomes a load close to a no-load condition, and rotating speed of a motor 25 increases. When rotating speed of the motor 25 becomes equal to or larger than a preset value, a control part display a warming to urge the replacement of the filter 13, and switches it to a developer recovering mode by operating a retreat means. A magnetic pole of a second magnetic force sleeve 16 is rotatably retreated from an opposite position of a first magnetic force sleeve 15. Therefore, a developer supplied by the first magnetic force sleeve 15 is not sucked in the second magnetic force sleeve 16, and is carried to the rotational directional downstream while being still adsorbed to a surface of the first magnetic force sleeve 15. Therefore, the developer is not clogged after the filter 13 is damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a separating device capable of separating a non-magnetic substance from a magnetic powder and an electrophotographic image forming device utilizing the developer removed from an electrophotographic photosensitive member after image formation using the separating device. Regarding

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a copying machine, a latent image is formed by selectively exposing an electrophotographic photosensitive member uniformly charged by a charging device, and the latent image is developed by a developing device. The developer is visualized and the image formed by the developer is transferred to a recording medium to record an image.

In such an apparatus, the developer remaining on the electrophotographic photosensitive member after transferring the developed image is removed and collected by the cleaning means.

Today, the removed developer is reused, but in the case of reusing such recovered developer, it is necessary to regenerate the recovered developer once. This is because the developer once used for image formation and collected by the cleaning means contains foreign matter such as paper dust of recording paper, which is a recording medium, dust in the air, and agglomerates and coagulants of the developer. If you return it to the developing device and reuse it,
There is a possibility that the quality of the developed image will be deteriorated due to such foreign matters.

As a developer regenerating method therefor, a mesh filter has been conventionally considered, but in using the recovered developer by causing clogging of the mesh or passing a small foreign substance as it is. There was a problem. In particular, if the mesh is made fine so as to remove even small foreign matter, the clogging of the collected developer with the mesh becomes noticeable, resulting in a trade-off.

Therefore, the magnetic force sleeves are arranged above and below via the mesh, the recovery developer is supplied from the lower side, and the magnetic developer adhered to the lower side magnetic force sleeve is forced to the upper magnetic force sleeve via the mesh. A separating device has been proposed which conveys magnetically using magnetic force.

[0007]

SUMMARY OF THE INVENTION The above separating device vibrates the filter in order to prevent clogging of the mesh filter when agglomerated developer is attracted to the upper magnetic sleeve. The cohesive developer adhering to is destroyed.

Therefore, the filter is constantly subjected to the load of vibration imparting during the separating operation, and as the durability progresses, the filter may be fatigued and eventually may be damaged. When the filter is damaged, vibration is difficult to be transmitted, and the aggregated developer remains attached to the filter, which may cause clogging.

Further, if the filter is clogged,
Since the developer supplied from the lower magnetic sleeve does not move to the upper magnetic sleeve, the developer stays in that portion and the load applied to the developer supply portion of the lower magnetic sleeve increases. Become.

The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to retain magnetic powder such as magnetic developer in the separator even when the filter is clogged. Another object of the present invention is to provide a highly reliable separating device and an electrophotographic image forming apparatus using the separating device.

[0011]

A typical structure according to the present invention for achieving the above-mentioned object is a non-magnetic filter through which magnetic powder can pass in a separation device for separating magnetic powder, A first magnetic force generating means disposed on one side of the magnetic filter and rotatable for supplying magnetic powder; and a first magnetic force generating means disposed on the side facing the first magnetic force generating means with the non-magnetic filter interposed therebetween. A second magnetic force generating means that is rotatable to generate a magnetic force stronger than that of the first magnetic force generating means and recovers the magnetic powder supplied from the first magnetic force generating means, and a vibration for vibrating the non-magnetic filter. Granting means,
Recovery means for recovering the residue remaining in the first magnetic force generation means, detection means for detecting a vibration applying state by the vibration applying means, and retraction means for retracting the second magnetic force generating means. And a control means for controlling the retracting means to operate so as to retract the second magnetic force generating means from the first magnetic force generating means in response to a signal from the detecting means.

In the above structure, for example, when the filter is damaged, the load applied to the vibration applying means for vibrating the filter changes. When this is detected and the control means retracts the second magnetic force generating means, the magnetic powder supplied by the first magnetic force generating means is not adsorbed by the second magnetic force generating means. Then, the magnetic powder is directly recovered by the recovery means, and the magnetic powder does not stay in the separation device.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the structure of an electrophotographic image forming apparatus according to an embodiment of the present invention and a developer separating apparatus used in the image forming apparatus will be described.

[First Embodiment] FIGS. 1 to 12 show a copying machine and a separating apparatus which are electrophotographic image forming apparatuses according to a first embodiment. FIG. 1 is an explanatory view of the entire structure of the copying machine. FIG. 2 is a structural explanatory view of sending the collected developer to the developing means, and FIGS. 3 to 12 are structural explanatory views of the developer separating device.

Here, as the order of the description, the entire structure of the copying machine will be described first, and then the structure of the developer separating device will be described.

{Overall Structure of Image Forming Apparatus} First, copying machine A
The overall configuration of will be described with reference to FIGS. 1 and 2. In FIGS. 1 and 2, reference numeral 1 denotes a document reading unit, which illuminates a document placed on a platen glass 1a with an illumination lamp 1b and scans the lamp 1b and a scanning reflection mirror 1c1 to scan the document. The reflected light is radiated to the photoconductor drum 2 which is an electrophotographic photoconductor through the mirror 1c1 and the reflection mirrors 1c2, 1c3, 1c4, 1c5, 1c6, and the lens 1d having the focusing and zooming function, and the Form a latent image.

The photosensitive drum 2 has a photosensitive layer on its surface, and can be rotated by the main motor 3 in the direction of the arrow in FIG. 1 in accordance with the image forming operation. Around the photosensitive drum 2, a charging unit 4, a developing unit 5, a transfer unit 6 and a cleaning unit 7 for uniformly charging the surface of the photosensitive drum are arranged. The surface of the rotating photosensitive drum 2 is uniformly charged by the charging means 4, and an electrostatic latent image is formed by the exposure from the document reading means 1, and the developing means 5 magnetically develops the electrostatic latent image. The agent is transferred to form a developed image.

The developing means 5 sends the developer in the developer hopper 5a to the developing roller 5c containing a fixed magnet by the feeding member 5b, rotates the developing roller 5c, and imparts a triboelectric charge by the developing blade. A developer layer is formed on the surface of the developing roller 5c, and the developer is transferred to the photoconductor drum 2 according to the latent image to form a developed image and visualize it.

Then, the developed image is transferred to the recording medium 9 conveyed by the conveying means 8 by the voltage application of the transfer means 6.
The transfer means 6 has a transfer charger 6a and a separation charger 6b. The transfer charger 6a applies a voltage having a polarity opposite to that of the developing toner to transfer the developed image to the recording medium 9 conveyed, A voltage is applied to the recording medium 9 after the image transfer by the separation charger 6b to separate the recording medium 9 from the photoconductor drum 2.

The developer remaining on the surface of the photosensitive drum 2 after the developed image is transferred to the recording medium 9 is scraped off by the cleaning blade 7a and removed by the cleaning means 7 which collects it in the collected developer reservoir 7b, which will be described later. The developer and the foreign matter are separated by the separating device B to separate the developer hopper 5
Send to a.

On the other hand, in the constitution of the conveying means 8, upper and lower cassettes 8a1 and 8a2 are mounted below the main body of the apparatus, and recording media 9 stored in the respective cassettes 8a1 and 8a2 are picked up one by one by pickup rollers 8b1 and 8b2. It can be supplied to the pair of registration rollers 8c. The cassette 8a1, 8
The recording medium 9 supplied from b2 or the manual feed tray 8d is
The registration roller pair 8c is driven and conveyed in synchronization with the image forming operation by the photosensitive drum 2, and the developed image is transferred at the position of the transfer unit 6 as described above. Then, the recording medium 9 after the image transfer is driven by the driving belt 10a by the conveyor belt 8e.
Then, the transfer image is conveyed to a fixing means 10 including a heating and pressing roller 10b having a built-in heater, heat and pressure are applied by the fixing means 10 to fix the transferred image, and the transfer image is discharged to a discharge tray 8g by a discharge roller pair 8f. The image forming apparatus has a re-conveying guide portion 8h for conveying the recording medium 9 once image-formed to the image transfer position again, an intermediate tray 8i, and a re-conveying portion 8j.

Further, in the copying machine A according to this embodiment, the automatic document feeder 11 is mounted on the upper part of the original glass 1a so that a plurality of originals can be automatically separated and fed.
Since the structure of the automatic document feeder 11 is publicly known, a detailed description thereof will be omitted.

{Developer Separating Device} In the copying machine A according to the present embodiment, the magnetic developer, which is the magnetic powder collected by the cleaning means 7, is separated by the developer separating device B to remove foreign matters. Developing means 5 by the conveying pipe 12 shown in FIG.
The developer is supplied to the developer hopper 5a for reuse.

Next, the basic structure of the separating apparatus B will be described with reference to FIGS. 3 and 4. Incidentally, FIG. 3 is a sectional explanatory view of the separating device in the sleeve rotation axis direction, and FIG. 4 is a sectional view of the separating device.

The separating device B is made of a non-magnetic material (for example, non-magnetic stainless wire, non-magnetic brass wire, nylon fiber, etc.) and has a mesh filter 13 having a mesh roughness several times the particle size of the developer. It is arranged horizontally, and its periphery is supported by the support member 14, and the flexible sheet 14 is sandwiched between the support member 14 so as to sandwich the front and back surfaces of the filter 13.
a and 14b (for example, thin-layer stainless steel plate) are attached. Further, a first magnetic force sleeve 15 serving as a first magnetic force generating means is disposed below the filter 13, and a second magnetic force generating means is disposed above the filter 13 so as to face the first magnetic sleeve 15. A second magnetic sleeve 16 is arranged.
The magnetic force sleeves 15 and 16 are respectively the magnetic force generating members 15
Rotatable cylindrical sleeves 15b, 16 containing a, 16a
b.

As the magnetic force generating members 15a and 16a, there are electromagnets, magnets and the like, but the magnets are superior in terms of simplicity of construction and cost. Regarding the cylindrical sleeves 15b and 16b, there are resins, stainless steel, aluminum materials, etc., but aluminum materials are superior in terms of cost and durability.

Cylindrical sleeve of the magnetic sleeves 15 and 16
As shown in FIG. 3, 15b and 16b are rotatably provided by driving means (not shown) via gears 17a and 17b.

Further, as shown in FIG. 4, the magnetic force generating members 15a and 16a of the magnetic force sleeves 15 and 16 have a polarization structure of two or more divisions in the sleeve rotation direction (the magnetic force sleeve of this embodiment).
15 has N1, S1, N1, S1, ..., and magnetic force sleeve 16 has S2, N2, S2, N2, ...) so that different magnetic poles (N1 and S2) face each other. , And the cylindrical sleeves 15b and 16b are rotatable. The magnetic force of the opposing magnetic pole portions of the magnetic force sleeves 15 and 16 is stronger than the magnetic force of the first magnetic force sleeve 15 (N1 <S2, S1 <N2).
) It is set.

Further, in FIG. 4, reference numerals 18 and 19 denote developer conveying screws, and the first conveying screw 18 conveys the developer collected from the cleaning means 7 from the back side to the front side. The second conveying screw 19 is provided in the developer collecting section 20, and conveys the developer from which foreign substances have been separated from the front side to the rear side and conveys the developer to the hopper 5a of the developing means 5 through the above-mentioned conveying pipe 12. Is.

Further, a doctor blade 21 for regulating the layer thickness of the developer conveyed along the peripheral surface of the roller 15 is close to the peripheral surface of the first magnetic force sleeve 15. A scraping blade 22 for scraping the developer conveyed along the peripheral surface of the roller 16 and dropping it to the developer collecting portion 20 is also in contact with the peripheral surface of the second magnetic force sleeve 16.

Further, the first magnetic force sleeve 15 side is provided with a recovery means 23 for recovering the residue remaining without moving to the second magnetic force sleeve 16 side via the filter 13. As shown in FIG. 4, in the collecting means 23 in this embodiment, the non-magnetic brush 23a is in contact with the surface of the first magnetic force sleeve 15, and the non-magnetic brush 23a is opposite to the rotating direction of the first magnetic force sleeve 15. The brush 23a is configured to be driven to rotate at a low speed, and the residue scraped off by the brush 23a is to be collected in the lower collection container 23b.

The filter 13 that allows the developer to pass therethrough
Are configured to vibrate by the vibration applying means. As shown in FIGS. 4 and 5, this vibration applying means has a flexible sheet 14 in which a cam 24 is attached to a filter 13.
It is rotatably mounted in contact with a, and the cam 24 is rotated by a motor 25. The flexible sheets 14a and 14b preferably have a thickness of about 0.05 mm to 0.2 mm.
Even if b is continuously bent by the cam 24, it is sufficiently restored because it is a thin layer. By vibrating the filter 13, the aggregated developer can be destroyed and passed through the filter 13 when the aggregated developer adheres to the filter 13.

As shown in FIG. 4, the magnetic sleeve
A magnetic sheet metal 26a and a magnet 26b are arranged between the magnetic powder separating portion composed of 15 and 16 and the cam 24 with the filter 13 interposed therebetween, and a concentrated magnetic field is formed to separate the separating portion from the cam portion. The magnetic powder that scatters into is supplemented.

Further, this separating device detects the vibration state applied to the filter 13, and when the filter 13 is judged to be damaged, the magnetic pole of the second magnetic force sleeve 16 faces the first magnetic force sleeve 15. It is configured to retreat from the position by rotation.

In this embodiment, as the vibration state imparting detection means for the filter 13, the number of revolutions by the motor 25 is detected,
The configuration is such that it is determined that the filter 13 is damaged when the cam 24 rotates at the set number of revolutions or more.

As a configuration for detecting the motor rotation speed, as shown in FIG. 4, a rotation detection flag 27a is attached to the other side of the motor rotation shaft having a cam 24 attached to one side,
A transmissive photosensor 27b including a light emitting element and a light receiving element is provided so as to sandwich the flag 27a. The photo sensor 27b detects the rotational speed of the flag 27a to detect whether or not the motor 25 is rotating at a set rotational speed or more.

In this embodiment, in addition to the detection of the motor rotation speed, a current detection means for detecting the load current supplied to the motor 25 is provided, and the load current is detected as described later. Therefore, the filter 13 can be detected to be broken.

Next, the structure of the retracting means for rotating and retracting the second magnetic force sleeve 16 when it is determined that the filter 13 is damaged will be described.

As shown in FIGS. 6 and 7, a magnetic pole fixing member 28 is connected to the shaft end portion 15a of the first magnetic force sleeve 15 and is fixed to the device frame 29. On the other hand, a magnetic pole fixing member 30 is connected to the shaft end portion 16a of the second magnetic force sleeve 16, and one end of the fixing member 30 is linked to one end of a lever 32 rotatable about a shaft 31. Are connected. A tension spring 33 is locked to one end of the lever 32, and a solenoid 34 is connected to the other end.

As a result, when the solenoid 34 is off, the lever 32 is pulled in the clockwise direction about the shaft 31 by the urging force of the spring 33, as shown in FIG. 30 is brought into contact with the stopper 35 and positioned. At this time, the magnetic poles of the opposing portions of the second magnetic force sleeve 16 and the first magnetic force sleeve 15 face each other, and a concentrated magnetic field is generated between them.

On the other hand, when the solenoid 34 is turned on, FIG.
As shown in (b), the lever 32 rotates counterclockwise around the shaft 31, and the magnetic pole of the second magnetic force sleeve 16 is rotated and retracted from the position facing the first magnetic force sleeve 15. .

The evacuation means is controlled by the control means in response to a signal from the detection means. This control means is shown in FIG.
As shown in FIG. 3, the control unit 36 inputs the rotation speed signal from the rotation speed detection means (photosensor in this embodiment) 27b of the motor 25 and the current value signal from the load current detection means 37 of the motor 25, which will be described later. When the value reaches the set value as described above, a warning is displayed on the display means 38 and the solenoid
34 is operated to retract the magnetic pole of the second magnetic force sleeve 16.

Next, the operation of the separating apparatus B including the control operation by the control means will be described. When the developer is collected in the developer reservoir 7b of the cleaning means 7 by the image formation, the developer is carried into the separating device B by the carrying screw 18. Here, the developer is the first magnetic force sleeve.
The magnetic force is applied to the upper surface of the magnetic sleeve 15, the upper portion of the magnetic sleeve 15 is conveyed upward as the magnetic sleeve 15 rotates, and the doctor blade 21 regulates the layer thickness to a predetermined value. Then, the developer sent to the separating portion opposed to the second magnetic force sleeve 16 receives the first magnetic force sleeve 15
The magnetic force of the second magnetic force sleeve 16, which is stronger than the magnetic force of, is attracted upward. Since the mesh filter 13 has a gap several times larger than the particle size of the developer, the developer smoothly passes through the filter 13 as shown in FIG.
Attach to the magnetic sleeve 16.

As the durability increases, the partially agglomerated developer adheres to the filter 13 or does not pass through the filter 13, causing a so-called clogging phenomenon. The connected cam 24 first gives vibration to the flexible sheets 14a and 14b, and further gives vibration to the filter 13 via the flexible sheets 14a and 14b. The vibration destroys the agglomerates and the developer is easily filtered.
You will pass 13.

The non-magnetic substance (foreign matter such as paper dust) separated from the developer adheres to the lower side of the filter 13,
The vibration applied to the filter causes it to lose its adhesive force with the filter 13 and falls downward due to its gravity.

The developer from which the foreign matters have been separated by passing through the filter 13 as described above is conveyed as the second magnetic force sleeve 16 rotates, and is scraped from the second magnetic force sleeve 16 by the scraping blade 22. It is scraped off to 20, and conveyed to the outside of the separating apparatus B by the conveying screw 19. Then, this developer is transported to the hopper 5a of the developing means 5 by the transport pipe 12 shown in FIG. 2 and used again for development.

On the other hand, the foreign matter separated from the developer in the separating section drops onto the first magnetic force sleeve 15 and is conveyed, and is separated from the surface of the first magnetic force sleeve 15 by the non-magnetic brush 24. Since the non-magnetic brush 24 is in contact with the first magnetic force sleeve 15 by a small contact pressure, the first magnetic force sleeve 15 is
The foreign matter adhered with a weak force is scraped off.

As described above, in the normal state, even if the aggregated developer adheres to the filter 13, the filter 13 vibrates and is destroyed, so that clogging does not occur.

However, the filter 13 is, as shown in FIG.
The cam 24 repeatedly receives forced displacement through the flexible sheets 14a and 14b. In particular, the flexible sheet 14a,
Since stress is likely to concentrate on the peripheral portion of 14b, the load that the filter 13 receives at this portion is large. Therefore, the filter 13 may be damaged if it is used for a long period of time. When the filter 13 is damaged, vibration is not transmitted to the filter 13 even if the cam 24 rotates. Then, the cohesive developer adhering to the filter 13 is not destroyed and the filter 13
Will remain attached to the filter, or the filter 13 will be clogged.

Therefore, in this embodiment, the relationship between the sliding resistance generated between the rotating cam 24 and the filter (portion of the flexible sheet 14a) and the rotational speed of the motor 25 is set as shown in FIG. That is, the rotation speed of the motor and the sliding resistance are in inverse proportion to each other. As the sliding resistance increases, the rotation speed of the motor decreases. To increase. Therefore, when the control unit 36 detects that the motor rotation speed is equal to or higher than the set value α (rpm) by the signal from the photo sensor 27b, it is determined that the filter 13 is damaged.

When the motor rotation speed becomes equal to or higher than the set value α, the control section 36 displays a warning message on the display means 38 for prompting the replacement of the filter 13 and operates the retracting means to switch to the developer collecting mode.

This is because the developer supplied from the first magnetic force sleeve 15 is sucked by the second magnetic force sleeve 16 when the separating operation of the developer is continued with the filter 13 being damaged. Since the developer does not pass through due to clogging or the like, the portion is clogged at the portion. Therefore, as shown in FIG. 7 (b), the solenoid 34 is turned on.
Then, the lever 32 is rotated (the rotation angle depends on the strength of the magnetic force and the half width, but it is appropriate to set it within the range of 30 ° to 80 °). 1 The magnetic force sleeve 15 is rotated and retracted from the facing position. As a result, the concentrated magnetic field between the magnetic force sleeves 15 and 16 is released, and the developer supplied by the first magnetic force sleeve 15 is not attracted to the second magnetic force sleeve 16 as shown in FIG. It is conveyed to the downstream side in the rotation direction while being adsorbed on the surface. Then, the developer is captured by the non-magnetic brush 23a, and is collected together with the non-magnetic material in the collection container 23b.

Therefore, even if the developer is continuously supplied into the separating device B even after the filter 13 is damaged, the developer does not stay in the filter 13 portion, so that the inside of the separating device is prevented. Therefore, there is no possibility that the developer will be clogged. Further, the operation of the image forming apparatus is not hindered, and the image formation can be normally performed.

At this time, the user can know the damage of the filter 13 by looking at the warning display displayed on the display means and can replace the filter 13.

When the control unit determines that the filter 13 is damaged, the evacuation means is operated as described above, and at the same time, the driving of the separating apparatus B is controlled to stop, or alternatively At the same time, the image forming apparatus itself may be controlled so as to be stopped.

[Second Embodiment] In the first embodiment described above, the number of rotations of the motor 25 for vibrating the filter 13 is the set value α.
Although an example has been shown in which it is determined that the filter 13 has been damaged when the above conditions have been reached.When a drive motor of a rotation control system is used as the motor 25, the sliding resistance between the cam 24 and the filter fluctuates. However, the rotation speed of the motor 25 does not change. Therefore, when such a motor is used, the load current supplied to the motor 25 and the sliding resistance are in a proportional relationship as shown in FIG. As the resistance decreases, the load current also decreases.

Therefore, by detecting the motor load current by the load current detecting means 37, the current is set to the set value β.
(A) It may be configured to judge that the filter 13 is damaged when it is detected that

When the load current becomes equal to or less than the set value β, the control unit 36 displays a warning message on the display unit 38 to prompt replacement of the filter 13 and operates the retreat unit to enter the developer recovery mode. Switch. Even with this configuration, the same effect as that of the above-described first embodiment can be obtained.

[Other Embodiments] In the above-described embodiments, the magnetic developer is exemplified as the magnetic powder, but the separating apparatus according to the present invention separates the magnetic powder when the non-magnetic foreign matter is mixed. The magnetic powder to be separated need not be limited to the magnetic developer.

In the above-described embodiment, the electrophotographic photosensitive member is not limited to the photosensitive drum,
For example, the following are included. First, a photoconductor is used as the photoconductor, and examples of the photoconductor include amorphous silicon, amorphous selenium, zinc oxide, titanium oxide, and organic photoconductor (OPC). The shape on which the photoconductor is mounted includes, for example, a rotating body such as a drum or a belt, and a sheet. In general, a drum-shaped or belt-shaped one is used. For example, in the case of a drum-type photoconductor, a photoconductor is deposited or coated on a cylinder of an aluminum alloy or the like. It is.

Further, in the above-mentioned embodiment, the copying machine in which the electrophotographic photosensitive member, the developing means, the cleaning means and the like are directly attached to the main body of the apparatus has been exemplified. The present invention can also be applied to an image forming apparatus that is made into a cartridge and is detachable from the apparatus main body.

Further, in the above-mentioned embodiment, a copying machine is exemplified as the image forming apparatus, but the apparatus is not limited to the copying machine as long as it is an apparatus for forming an image by using a developer, and for example, a printer, a facsimile machine or the like. However, it is possible to apply the separation device of the present invention.

[0063]

As described above, according to the present invention, even if the filter of the separation device is damaged, it is possible to detect the damage and prevent the magnetic powder from staying in the device. It is possible to prevent clogging in the device.

Further, in the electrophotographic image forming apparatus using this, the image forming operation can be normally performed even if the filter is damaged.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the configuration of a copying machine using an electrophotographic method.

FIG. 2 is an explanatory diagram of a configuration for sending a collected developer to a developing unit.

FIG. 3 is a cross-sectional view of the separation device in the sleeve rotation axis direction.

FIG. 4 is an explanatory view of a configuration cross section of a separation device.

FIG. 5 is an explanatory diagram of a vibration configuration of a filter.

FIG. 6 is an explanatory diagram of a configuration of a retracting unit.

7A is an explanatory view of a state in which the magnetic pole of the second magnetic pole sleeve is not rotationally retracted by the retracting means, and FIG. 7B is an explanatory diagram of a state in which the magnetic pole of the second magnetic pole sleeve is rotationally retracted by the retracting means. .

FIG. 8 is a control configuration block diagram.

FIG. 9 is a diagram illustrating the separation of the developer.

FIG. 10 is a graph showing the relationship between the rotation speed of the cam rotation motor and the sliding resistance between the cam and the filter.

FIG. 11 is an explanatory diagram of a developer conveyance state when the magnetic pole of the second magnetic pole sleeve is rotationally retracted.

FIG. 12 is a graph showing the relationship between the load current of the cam rotation motor and the sliding resistance between the cam and the filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Original reading means 1a ... Original table glass 1b ... Illumination lamps 1c1 to 1c6 ... Reflecting mirror 1d ... Lens 2 ... Electrophotographic photoreceptor 3 ... Main motor 4 ... Charging means 5 ... Developing means 5a ... Developer hopper 5b ... Feeding member 5c Development sleeve 6 ... Transfer means 6a ... Transfer charger 6b ... Separation charger 7 ... Cleaning means 7a ... Cleaning blade 7b ... Collected developer reservoir 8 ... Conveying means 8a1, 8a2 ... Cassette 8b1, 8b2 ... Pickup roller 8c ... Registration roller 8d ... Manual feed tray 8e ... Conveyance belt 8f ... Ejection roller 8g ... Ejection tray 8h ... Re-conveyance guide section 8i ... Intermediate tray 8j ... Re-conveyance section 9 ... Recording medium 10 ... Fixing means 10a ... Drive roller 10b ... Heat pressing roller 11 ... Automatic document feeder 12 ... Transport pipe 13 ... Mesh filter 14 ... Support members 14a, 14b ... Flexible sheet 15 ... First magnetic force sleeve 15a ... Magnetic force generating member 15b ... Cylindrical sleeve 16 ... Second magnetic force sleeve 16a ... Magnetic force generating member 16b ... Cylindrical sleeves 17a, 17b ... Gears 18, 19 ... Conveying screw 20 ... Developer collecting section 21 ... Doctor blade 22 ... Scraping blade 23 ... Collection means 23a ... Non-magnetic brush 23b ... Collection container 24 ... Cam 25 ... Motor 26a ... Magnetic sheet metal 26b ... Magnet 27a ... Flag 27b ... Photo sensor 28 ... Magnetic pole fixing member 29 ... Device frame 30 ... Magnetic pole fixing member 31 ... Shaft 32 ... Lever 33 ... Spring 34 ... Solenoid 35 ... Stopper 36 ... Control unit 37 ... Load current detection means 38 ... Display means

Claims (6)

[Claims] 1. A separation device for separating magnetic powder, comprising: a non-magnetic filter through which the magnetic powder can pass, and a first magnetic filter disposed on one side of the non-magnetic filter and rotatable to supply the magnetic powder. A first magnetic force generating unit and a non-magnetic filter sandwiched between the first magnetic force generating unit and the first magnetic force generating unit, and a magnetic force stronger than that of the first magnetic force generating unit is generated and supplied from the first magnetic force generating unit. Second magnetic force generating means for recovering the magnetic powder, vibrating means for vibrating the non-magnetic filter, and recovery for recovering the residue remaining in the first magnetic force generating means. Means, a detection means for detecting the vibration applying state by the vibration applying means, a retracting means for retracting the second magnetic force generating means, and a signal from the detecting means for operating the retracting means. Separating apparatus characterized by having a control means for controlling so as to retract the second magnetic force generating means from the first magnetic force generating means. 2. The vibration applying means is configured to rotate a cam by a motor to vibrate the non-magnetic filter, and the detecting means detects a rotational speed of the motor or a load current for driving the motor. 2. The separating apparatus according to claim 1, wherein the control means is configured to operate the retreating means according to the rotation speed of the motor or the value of the load current. 3. The control means displays a warning when the rotation speed or load current of the motor reaches a set value, and controls the apparatus to stop.
Separation device as described. 4. The first magnetic force generating means is disposed below the non-magnetic filter, and the second magnetic force generating means is disposed above the non-magnetic filter.
2. The separation device according to claim 1, further comprising magnetic force generating means. 5. The separation device according to claim 1, wherein the magnetic powder is a magnetic developer. 6. An electrophotographic image forming apparatus for forming an image using a magnetic developer, an electrophotographic photoreceptor for forming an electrostatic latent image, and a development for developing the electrostatic latent image with a magnetic developer. Means, a transfer means for transferring the developed image to a recording medium, a cleaning means for removing the developer remaining on the electrophotographic photoreceptor after transferring the image, and a cleaning means for removing the developer from the electrophotographic photoreceptor. An electrophotographic image forming apparatus comprising: the separating device according to claim 5 for removing a non-magnetic substance from a developer and supplying the non-magnetic substance to the developing means.