JPS5986080A - Recovering method of residual toner - Google Patents

Abstract

PURPOSE:To recover residual toner easily to a developng device without the fatigue of a developer and fogging by recovering the residual toner collected by a cleaning member after destaticization or electrification to a specific polarity. CONSTITUTION:The bank 22 of residual toner collected to a photosensitive drum 1 by a cleaning blade is conveyed by the drum 1 by the movement of the blade 21 and recovered to the developing device 8 equipped with a magnetic brush roll 9, etc. This bank 22 is processed by AC destaticization by electrification to the same polarity with toner through a corona discharger 3 whose power supply is selected while used in common for uniform electrification. Consequently, the bank 22 is recovered easily to the device 8 with the fatigue of the developer, fogging, contamination, etc.

Description

[Detailed description of the invention]

The present invention relates to a residual toner collection method for collecting residual toner on an endless charge holding member rotating along a predetermined path into a developing device using a dry developer. For example, an electrostatic latent image corresponding to an original document formed on a rotating electrophotographic photosensitive drum is developed with toner using a developing device using a dry developer, and this toner image is transferred to copy paper to make a copy. In electrophotographic devices, after the toner image is transferred to the copy paper, the RC1+ original drum is cleaned to remove residual toner that was not transferred to the copy paper before forming the next static latent image. It is necessary to
As such leaning devices, there have conventionally been proposed devices using a fur brush, devices using a blade, devices using a magnetic brush, and the like. On the other hand, the current 1# using dry developer like this! Electrophotography 4' in which the electrostatic latent image formed on the 118-source drum is developed with toner by the device [-Kui 11
After the toner image is transferred to the copy paper, the remaining toner on the photosensitive drum is removed using a 1:4 printing method.

[It is a good idea to collect and reuse this. However, fur brush cleaning K i'(r
In general, the residual toner removed by the fur brush is captured by the filter using the air flow generated by the air suction device f1, and the toner is then pierced by the filter. Because it requires I'4 formation, IM He becomes large, and therefore electronic copy CL Rumor! i'? There is a problem that the whole thing becomes large. The blade cleaning device cleans the dirt by bringing the blade made of a bullet material such as urethane into contact with the photosensitive drum.
In addition, since the residual toner on the photosensitive drum 1 is collected by a blade, it can be collected in the developing device and reused. However, the conventional method using this type of cleaning device
In the Vjt&, the residual toner collected by the blade is automatically collected into the developing device by a separate toner conveying means having a flexible wall screw, etc., which makes the device expensive and reduces the toner. There is a problem that the (1η composition of the conveyance means becomes double i8). Also, the magnetic brush cleaning seat Ia is also used as the magnetic brush developing device, so that the cleaned toner is transferred to the developing device (σ) as it is. Unlike other methods, routine maintenance work to remove the cleaned toner outside the electrophotographic unit is required, and maintenance work such as IM6 is required to return the cleaned toner to the current 1mA blue color. This method has the advantage that the equipment is not insecure, and is extremely advantageous in terms of lower costs and improved maintainability of the equipment. But a developing device like this? If it is also used as a cleaning device, the image forming device is normally placed between the latent image forming section and the toner image transfer section 61, so the display device is placed between the toner image transfer section and the A7 image forming section. '11L with dedicated cleaning device
Therefore, when making continuous copies, at least two photosensitive drums are required to make one copy. It is necessary to rotate the photosensitive drum, making it difficult to use and making it difficult to use.In addition, it is necessary to make the outer length of the photosensitive drum more flexible than the maximum length of the copy paper, so there is a problem that the entire mounting becomes large. be. Additionally, while the current rod holder deposits toner on the photosensitive drum, the cleaning device has the opposite effect of picking up residual toner on the photosensitive drum, so cleaning may not be performed sufficiently. . On the other hand, if the residual toner on the photosensitive drum is simply collected in the developing device and reused, this reused toner has already been subjected to electrical action during the transfer process, etc., and is then collected in the developing device. During this time, the polarity tends to be reversed, and recovery of the toner of the reverse polarity promotes fatigue of the developer and causes fogging. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide a method for recovering residual toner that can easily collect residual toner on a charge retention member into a developing device without causing developer fatigue or fogging. It is something. The present invention provides an endless T that rotates along a predetermined path.
When collecting the toner on the top of the load holding member using a developing device using a dry developer, a cleaning member is brought into contact with the charge holding member to collect the residual toner in a small area on the charge holding member. , ri & hoe cleaning member Before the residual toner collected at a distance from the load holding member is conveyed to and collected by the 1111 developing device by rotation of the charge holding member, this pre-wet residual toner is removed. 'i17+ or charging with the same polarity as that of the toner. 0 Referring to the drawings below, 11 will be described in detail. 0 Figure 1 shows the method of the present invention. An electronic copy of the actual bTb-ej-
Za iK? This is a diagram showing the configuration of an example of the zero element drum l.
rotates in the direction of the arrow at the start of the copying operation, and after defrosting and erasing the residual 11 moe with uniform 14 light from the lamp 2, the corona charger 3 uniformly '::f rl'
The original to be copied is placed 16 on the movable document table 4 and begins to move in the direction of the arrow, and is illuminated by the illumination lamp 5 and the σ reflector 6. It is projected onto the photosensitive drum 1"-, and thus! An electrostatic image corresponding to the original image is formed on the photosensitive drum 1. This electrostatic image uses a dry developer. This toner group is collected in advance with the copy paper sent out from the cassette 11 by the pickup roller 11 and the paper feed roller 12, and transferred to the copy paper by the action of the transfer corona 1 and the paper feed roller 12. This copy paper has a peeling corona strip i11+,
After being removed from the photosensitive drum 1 by the action of the toner roller 14, the toner image is sent to the fixing roller 15, where the toner image is fixed.
The paper is discharged onto a copy tray 17 by a discharge roller 16 . In the untrue bTIi example, a transfer corona 417m device 13 and a peeling corona charger 14 are arranged around the photosensitive drum 1.
A blade 21 made of an elastic material such as urethane is arranged between the toner f'1 transfer part and the static elimination lamp 2 so as to selectively contact the photosensitive drum \1, and this blade 21 is used for copying operation. σ) Bring the photosensitive drum l into contact with the copy start signal indicating the start, and sense this with the copy end No. 1g indicating the completion of the formation of the electrostatic latent image corresponding to the copy paper) 0 Z) 141C from the t drum J As shown in FIG. 2, a timing chart for obtaining three copies, the first copy start signal sl shown in FIG. Blade 2 as shown in Figure C
1 is brought into contact with the photosensitive drum 1, and a copy end signal 81 (
The blade 22 is moved away from the photosensitive drum 1 according to FIG. 2A). Thereafter, the copy start signal S2. S3
Connect the blade 21 to the rI & original drum l (copy-1 Hiiragi Ryo 1d No. 62 + e3-, J: Reno I
& : From IY Nidrum l to t'au. Blade 21 is spaced apart from J'■t drum l.What is the TI for i? There are many times when people copy, as shown in Fig.
C corresponds to the return time of the movable document table 4σ). Furthermore, where is the photosensitive drum 1? 4th number, this "invitation (ko118) copy"-G-kon・1 copy 1
1.57 After E3 occurred > J211: T between f
It rotates by 2, stops, and enters the waiting state for copying the next document. If the blade 21 is brought into contact with the A & era era name ram 1 selection 1 length like this, during the period when the blade 21 is in contact with the original drum 1, the blade 11 & original drum 1 will be 21, the residual toner on the photosensitive drum 1 is collected by the blade 21 as shown in FIG. 3A, and a toner 7 stagnation 22 is formed at the contact portion with the blade 21. This toner (retention 22) is released when the cleaning for one copy is completed, that is, when the copy end signal is activated, the blade 22 is moved as shown in FIG. 8B.
1 is separated from the photosensitive drum 1, and as the photosensitive drum 1 rotates, it is generally fed once, and is collected by the magnetic brush roller 9 with a development percentage ffi of 8 to the developing device 8, and is reused. In this example, the toner pool 22, which is generally fed as the photosensitive drum l rotates, is developed by the 1i8 brush roller 9 of the developing device'#8.
It is collected and reused at t8, but here the toner reservoir 22
If the corona charger 3 is activated when the toner is sent to the developing device 8 by +ta and collected by the rotation of the photosensitive drum 1, the polarity of the corona charger 3 is opposite to the original polarity of the toner. Because of this, is the toner reservoir 22 a corona zone? When the toner passes under the IZ device 3, it is attracted to the corona charger 3 and stains the area around the corona line, and also
Does the toner have a 4a polarity, which is the opposite of the normal polarity, due to the corona zone '1u device 8? fk TIE is happening υi;// g
Since the toner is collected in
It is conceivable to make the corona charger 3 inoperable during the period of i1 to 7, but even if the corona charger 3 is made inoperable in this way, will the developing device be damaged? Since the toner collected and reused in step y8 has already been subjected to electrical action during the transfer process, etc., the toner tends to have a reverse polarity before being collected in the developing device 8 next time. This also has the drawback of accelerating fatigue of the developer and making fog more likely to occur. Therefore, in this embodiment, during the period when the common toner reservoir 22 passes through the corona charger 3, the polarity of the corona charger 3 is switched and the toner reservoir 22 is connected to the AC band "1". (a) The polarity of the toner is changed by ]1j0 by making p constant or by applying direct current 'lk'r of the same polarity as the original toner polarity, and the toner is collected by the developing device 8. The inventor of the present invention places a photosensitive drum l on a static plate consisting of a load '11'.
When forming a +tZ latent image and developing it with toner of negative polarity, only during the period when the toner pool 22 that has been completely scraped on the photosensitive drum 1 passes through the corona zone TFir Wj 8, the source is set to positive polarity. An experiment was conducted in which continuous copying was performed by switching from a DC power source to an AC power source and AC was removed so that the polarity of the toner reservoir 22 became non-polar, and an experiment in which the toner in the toner reservoir 22 was changed from a positive DC power source to a negative DC power source. An experiment was carried out in which continuous copying was performed by aligning the polarity to negative polarity. In such an experiment, AC type 1J (XtL, "?j; L30
01Lz, 4KV to 6KV, but is it AC band as it is? Due to the characteristics of Fi, the toner reservoir 22 has a negative polarity '1.
1L, so to offset this, 100v ~ 60v
A positive DC voltage of 0v was biased. Also, negative DC′
Regarding the power supply, the voltage was set at -4KV to -8KV. In an experiment in which the toner reservoir 22 is charged to a negative polarity, the photosensitive drum 1 is also charged negatively by this band 1YL, so the connection between the corona charger 3 and the developing device 8 is An eliminator lamp 23 is disposed in between to remove static electricity from the photosensitive drum l. ” As a result of the two experiments, the number of copies per copy was 20,000 in both cases.
No fogging was observed even on the sheets. On the other hand, the toner reservoir 22
When I made continuous copies with this machine inactive for a period of time, the number of copies per copy was 1,0000 (fogging was noticeable after copying). In the example, when the blade 21 is brought into contact with the 7ti original drum 1 for cleaning, the residual toner is formed as a toner pool 22 on the photosensitive drum 1 with the first toner, and this toner pool 22 is removed by moving the blade 2
Before separating the toner from the redundant drum 2 and transporting it to the developing device 8 and collecting it by 10 revolutions of the g% C drum σ), the toner reservoir 22 is removed 1 (L or the original polarity of the toner is changed). 9, the blade 21 has a charger 13 for the transfer corona iY'C and a charger 414 for the corona charger Q(f) and From the toner 1 quadrant U part to the developer 4 position 8 σ) By placing it at an arbitrary position 1θ, the majority σ)
Develop residual toner 41? Although it can be easily recovered at ¥8, it effectively prevents the toner pool 22 formed by the Jg:tq insects of the blade 21 from spilling out due to gravity (1) and efficiently removes the residual toner from the development lump 1a8. In order to collect the photosensitive drum J, connect the contact point between the I tooth root drum L and the blade 21 and the center of the photosensitive drum J as shown in Fig. 5.
The angle of the haze to the vertical direction is θ1, development 14 ti(?
When the angle of the line connecting the center of the magnetic brush roller 9 and the center of the photosensitive drum l with respect to the vertical direction is 02,
0≦θl≦45°, 45°≦02'; 1.35° is preferable.
It should be possible to recover more than 90% of the residual toner on the surface by developing it. Note that the + invention is not limited only to the above-mentioned example, and many changes and modifications are possible. For example, in the above-mentioned example, the corona charger 3 uniformly charges the photosensitive drum l.
By sharing the same power source and switching the power supply, AC charge removal of the toner reservoir 22 or DC band 'lB of the same polarity as the original toner storage property is performed.
A separate ζV corona charger may be attached to perform static neutralization and DC band 'ilL. In this case, toner 7
When performing AC static neutralization or DC charging of the marsh 22, it is preferable to deactivate the corona 1111 (3). However, as shown in Figures 4 to 6, the photosensitive drum (1σ) is placed near the blade 21. The toner receiver 24 is installed 1jq on the upstream side in the rotational direction.
``(S, this hA may be configured to catch the topoo falling from the toner reservoir 22 due to gravity. The force of contaminating the inside with toner (with None 1, it is also easy to clean / l?).Also, ``-ν1 is!,: (with +IJ, the plate ° 21 is felt for each copy)Y ; From l'lam I:; I tried to make it a space, but 4 u e pieces σ)
In addition, in the above example, it is 1σ) from the blade.
& I tried to make a 22 minute 1 SO on one original drum, but the photosensitive drum IG was not the same as iJ+! ＃＜
(+ It is also possible to provide a plurality of blades that come into contact with the toner so as to form toner pools at multiple locations on the photosensitive drum 1. Furthermore, the cleaning section O A6 or the blade σ)
However, in the above-described example, the charge retaining member is a photosensitive drum, but it may also be a belt-like member. Developing and transferring the formed electrostatic latent image on the electrophotographic photoreceptor is not limited to the secondary photographic device; It can also be effectively applied to electrophotographic devices, facsimile machines, electrostatic printing machines, etc. that perform toner development on a dielectric material and transfer to copy paper.As described above, in the present invention, The cleaning member is selectively brought into contact with the charge retaining member to clean the charge retaining member, and the residual toner dyed by the contact with the cleaning member is conveyed to the developing device and collected by rotation of the charge retaining member. Since the collected residual toner is neutralized or made to have the same polarity as the original toner prior to development, the simple structure eliminates developer fatigue and fogging. , the residual toner on the charge retention member can be easily collected in the developing device, and the charge retention member can be cleaned more reliably than in the case where the developer replacement (a) and the cleaning device are both used. When applied to electrophotographic immersion, development and cleaning can be performed at the same time, making it easy to increase the speed, and also to reduce the amount of electrophotographic material that holds the toner image to be transferred. !, The load holding member can be made smaller, and the entire device can therefore be made smaller and cheaper.

[Brief explanation of drawings]

Figure 1 is a photo 11 of '+I Oji Ukiko carrying out the method of the present invention.
31: AA and B are photosensitive drums q) with the blades shown in FIG. 1. Fig. 4 is a diagram of a tortoise explaining the cleaning action. ? FIG. 5 is a diagram showing the configuration of the main parts of another example of the electrophotographic apparatus shown in FIGS. 1 and 4. FIG. 6 is a diagram showing the configuration of the main parts of another example of an electrophotographic apparatus that implements the method of the present invention. l...A&-)Y, 'Drum, 2...Static elimination lamp °, 3
...Corona・1η1FtJ device, Li...A2 centromere 41
", 6 units, 5...■ Mata 1s 1 lamp, 6...Reflector, 7...Fino (-lens array, 8...Visual image device KJ,!shi01ki brush roller, 10 ...) JSesoto, l]...Pickup roller, 12...1st
Paper roller, 18...Corona roller for transfer +1 @ device, ]4
...Conflict 11v5I JII corona zone 'iu device, 15.
...Fixing roller, 16...J'IF 1130-ra,
17...Copy tray, 21...Play 1:, 22
...Toner reservoir, 23...li'i1J+ lamp, 24...Toner gas.

Claims (1)

[Claims] 1. An endless ', +! that rotates along a predetermined path.
When the residual toner on the load holding member is collected by a developing device using a dry developer, a cleaning member is brought into contact with the charge holding member to reduce the residual toner to at least one location on the charge holding member. , the cleaning member is separated from the charge retaining member to remove the collected residual toner.
Prior to conveying to the developing device and collecting li:il by rotation of the l'U load holding member, the collected residual toner is neutralized or charged to have the same polarity as that of the toner. A method for collecting residual toner, characterized by: