JP3514591B2 - Image forming device - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to relates to a cleaning apparatus and an image forming apparatus using the image forming apparatus using an electrophotographic method or an electrostatic recording method.

[0002]

2. Description of the Related Art As a cleaning device for an image forming apparatus, for example, a cleaning blade and a fur brush as disclosed in Japanese Patent Laid-Open No. 3-91788, a collecting roller to which a predetermined bias voltage is applied, and a scraper member thereof. A so-called bias roller type cleaning device configured by is generally used.

On the other hand, in toners used in image forming apparatuses in recent years, the particle size is becoming smaller, and in order to ensure the fluidity of the toner when the particle size is made smaller, it is generally used with respect to the base particles of the toner. Several kinds of additives have been added.

[0004]

When such a toner is used, it is difficult to completely clean the additive substance contained in the toner having a reduced particle size, so that image formation is difficult. In many cases, the additive substance remains in the form of filming on the surface of the image carrier in the apparatus, or in the worst case, on the surface of the cleaning device or the surface of the collecting roller. Due to this phenomenon, the performance of the image forming apparatus deteriorates over time, which hinders good image formation. That is, when the filming of the additive substance on the surface of the image carrier is deteriorated, the exposure of the original image on the image carrier may be disturbed, or the partial toner stain may be generated on the surface of the image carrier. As a result, it has become difficult to continuously obtain good copied images.

The present invention has been made in view of the above problems in the cleaning device of the conventional image forming apparatus.
The lubricant substance effective for stabilizing the slip property (specifically, the sliding friction coefficient) within a predetermined range is continuously adhered to the place where filming due to the additive substance is likely to occur. It is an object of the present invention to provide an apparatus capable of performing the above.

[0006]

According to a first aspect of the present invention, in a cleaning device for an image forming apparatus, a visible toner image formed on a photoconductor is transferred to a transfer medium side, and then the photoconductor is formed. The toner powder remaining on the surface is removed by a fur brush and a cleaning blade arranged in contact with the surface of the photoconductor, and the toner powder attached to the fur brush is arranged in contact with the fur brush and has a predetermined bias voltage. Is electrically attracted and collected by a rotating collection roller that has been applied, is removed from the surface of the collection roller by a scraper member arranged in contact with the collection roller, and the removed toner powder is conveyed by a rotating toner discharge coil. , together with the discharged, click consisting in contact with the solid lubricant additive圧当against the surface of the recovery roller in contact with the fur brush
In an image forming apparatus having a leaning device, a temperature for obtaining a temperature measurement result for separately providing a rotation driving source of the collecting roller and variably controlling a rotation speed setting of the rotation driving source of the collecting roller provided separately. It is characterized by having a measuring means.

According to the second aspect of the present invention, after the visible toner image formed on the photoconductor is transferred to the transfer medium side, the toner powder remaining on the photoconductor is removed from the surface portion of the photoconductor. The fur powder and the cleaning blade placed in contact with the fur brush are removed, and the toner powder attached to the fur brush is electrically adsorbed and collected by the rotating collection roller which is arranged in contact with the fur brush and is applied with a predetermined bias voltage. Then, the scraper member disposed in contact with the collecting roller removes the collected toner powder from the surface of the collecting roller, and the removed toner powder is conveyed and discharged by the rotating toner discharging coil, and the collecting roller comes into contact with the fur brush. chestnut comprising contacting a solid lubricant additive圧当for on the surface
In an image forming apparatus having a burning device, a unit on the photoconductor for separately providing a rotation driving source for the collecting roller and variably controlling the rotation speed setting of the rotation driving source for the separately collecting roller. It is characterized by having means for obtaining an image occupancy rate per area.

[0008]

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view for explaining a main part of an image forming apparatus to which the present invention is applied and an image forming process thereof. In the figure, reference numeral 1 denotes a photoconductor drum 1, which is fed from the direction of arrow 3 through a document reading system and a writing system (not shown) on the rotating photoconductor drum 1 uniformly charged by the main charger 2. An electrostatic latent image is formed by exposing with the image light, and the electrostatic latent image is made into a toner visible image by the developing device 4. Next, the transfer charger 7 is transferred onto the transfer paper 6 sent in synchronization with the rotation of the photosensitive drum 1 via the paper supply path 5.
Transferring the more toner image on the photosensitive drum 1 in. The transfer paper 6 onto which the toner image has been transferred is separated from the surface of the photosensitive drum 1 by the separation charger 8. At this time, the photosensitive drum 1
After the transfer residual toner slightly remaining on the surface is controlled to have a predetermined polarity and charge amount by the charger 9,
It is removed by the cleaning device 10. Electric charges remaining on the photoconductor drum 1 after passing through the cleaning device 10 are discharged by the discharging lamp 11. On the other hand, the transfer paper 6 to which the toner image has been transferred and which has been sent from the separation charger 8 part
Is guided to the fixing device 13 by the transfer paper transport device 12,
The toner image is discharged to the paper discharge unit 14 in a state where the toner image is fixed by being heated and pressed.

Next, the structure and operation of the cleaning device 10 will be described. In the image forming process described above, the residual toner on the photosensitive drum 1 that has passed through the charging device 9 and is sent to the cleaning device 10 is transferred to the portion of the fur brush 17 that rotates beyond the inlet seal member 16. Reach The fur brush 17 is formed of a conductive fiber member, and a rotary roller 18 is provided so as to be in contact with the fur brush 17. As shown in FIG. 2, the rotating roller 18 includes a cored bar member 18a made of a conductive metal, a first adhesive layer 18b as an upper layer, a second adhesive layer 18c as an upper layer, and both adhesive layers 18b, 18c. The second adhesive layer 18c is composed of metal particles 18d disposed between the second adhesive layer 18c and the photosensitive drum 1. The first adhesive layer 18b is a conductive adhesive (for example, epoxy resin and carbon on epoxy resin) formed in a region corresponding to the arrangement length of the conductive fiber member of the fur brush 17 along the central axis direction of the metallic cored bar member 18a. Dispersed)). The second adhesive layer 18c is the first adhesive layer 18b.
It is formed of the same conductive adhesive as the first adhesive layer 18b in the same region as the above. The metal particles 18d are formed by uniformly dispersing and arranging insulating metal particles having a predetermined size.
It has a structure in which it is encapsulated and fixed in a sandwich shape between the adhesive layers 18b and 18c. The surface roughness of the second adhesive layer 18c is R.
Z has a predetermined roughness within the range of 3 to 20 μm. A predetermined bias voltage is applied to the collection roller 18. Therefore, the fur brush 17 is also in a state in which a bias voltage that is somewhat lower than the bias voltage applied to the collecting roller 18 is applied in a form in which the fur brush 17 also contacts the collecting roller 18.

With the above configuration, the residual toner on the photosensitive drum 1 sent to the fur brush 17 is first electrostatically collected on the fur brush 17 by the bias voltage applied to the fur brush 17. Next, as the fur brush 17 rotates, the fur brush 17 is guided to the collecting roller 18 and electrostatically collected on the collecting roller 18 by a bias voltage higher than the voltage applied to the collecting roller 18 to the fur brush 17. The toner collected on the collecting roller 18 is disposed on the scraper member 1 in contact with the collecting roller 18.
9 is sent with the rotation of the collecting roller 18, is scraped off by the scraping effect of the scraper member 19 and the surface of the collecting roller 18, and is dropped to the toner discharging coil 20 installed below the collecting roller 18 to discharge the toner. The cleaning device 10 is driven by the conveyance action caused by the rotation of the coil 20.
It is appropriately discharged to the outside of the device. For the blade member of the scraper member 19, for example, a nylon sheet material is used. The toner that remains on the surface of the photoconductor drum 1 without being captured and collected by the fur brush 17 and that has passed through the fur brush 17 as the photoconductor drum 1 rotates is located on the downstream side of the fur brush 17 in the rotation direction of the photoconductor drum 1. Photoconductor drum 1
The surface of the photoconductor drum 1 was scraped off by the rubbing force of the cleaning blade member 15 provided so as to rub the surface of the sheet, dropped on the fur brush 17, collected, and already collected by the fur brush 17. The toner is discharged out of the apparatus in the same manner as above.

A weight member 21, a solid lubricant holding member 22 made of sheet metal, and a solid lubricant 23 such as zinc stearate are arranged on the upper side of the collecting roller 18, and the solid lubricant holding member 22 is made solid. The lubricant guide portion 27 is slidably guided in the vertical direction in the figure. Solid lubricant 2
Reference numeral 3 has a length similar to that of the second adhesive layer 18c, which is the uppermost layer of the collecting roller 18, and is fixedly held by being attached to the lower side of the solid lubricant holding member 22 with a double-sided adhesive tape or the like. The weight member 21 placed on the upper part of the solid lubricant holding member 22 is in pressure contact with the upper portion of the collecting roller 18 (the pressure load W by the weight member 21 and the solid lubricant holding member 22). Scraper member 1
When the surface of the collecting roller 18 cleaned by 9 is guided to the contact portion with the solid lubricant 23 by further rotation of the collecting roller 18, the pressing contact force with the solid lubricant 23 and the collecting roller in this contact portion area. Due to the uneven shape of the surface of the second adhesive layer 18c of 18, the contact surface of the solid lubricant 23 is rubbed and polished, and the solid lubricant 23 is sequentially powdered to produce a powdered lubricant. The powdered lubricant thus generated reaches the contact portion with the fur brush 17 as the recovery roller 18 rotates, and most of the powdered lubricant is adhered to the surface of the collection roller 18. Is scraped and collected on the fur brush 17 by the rotation of.

The powdered lubricant slightly left on the collecting roller 18 helps prevent filming of the additive material in the toner on the surface of the collecting roller 18 thereafter. On the other hand, the powdered lubricant collected on the fur brush 17 is
As the fur brush 17 rotates, the fur brush 17 is carried to the contact portion between the fur brush 17 and the photosensitive drum 1, and most of the contact portion moves to the surface of the photosensitive drum 1. The powdered lubricant transferred to the surface of the photosensitive drum 1 is
As the photoconductor drum 1 rotates, it reaches the contact portion with the cleaning blade member 15, where a part thereof is scraped off and dropped onto the fur brush 17, and a part of the photoconductor drum 1 is also scraped off.
Is applied to the surface of the photosensitive drum 1 to help prevent the filming of the additive material in the toner on the surface of the photosensitive drum 1. Further, the powdered lubricant remaining on the fur brush 17 without being transferred from the fur brush 17 to the photosensitive drum 1, once transferred to the photosensitive drum 1, and then scraped off by the cleaning blade member 15. The powdered lubricant that has dropped onto the fur brush 17 will help prevent filming of the additive material in the toner on the fur brush 17 thereafter.

Although the surface of the solid lubricant 23 which is in sliding contact with the recovery roller 18 is sequentially abraded and worn, the solid lubricant holding member 22 is slid together with the weight member 21 by the solid lubricant guide portion 27. Since it is dynamically guided, it comes into sliding contact with the recovery roller 18 at a substantially constant pressure regardless of the wear state of the solid lubricant 23, and the solid lubricant 23 can be used stably until most of it is consumed. In the illustrated embodiment, since the cover 28 covering the solid lubricant guide portion 27 can be opened, it is easy to replace it with a new one when most of the solid lubricant 23 is consumed.

Next, the relationship between the outer diameter position tangential velocity vf of the fur brush 17 and the outer diameter position tangential velocity vk of the collecting roller 18 (see FIG. 3) will be described. Both outer diameter position tangential velocity vf, v
In the state in which the ratio (vk / vf) of k is changed to various values and the bias voltage VB is applied to the collecting roller 18,
FIG. 4 shows changes in the collection efficiency of the toner collection roller 18 on the fur brush 17. As is clear from the figure, the ratio of the tangential velocities vf and vk of both outer diameter positions is vk ≧ vf × 0.8.
The desired collection efficiency is set within the range where the relationship That is, in the above-described cleaning device 10, by setting the conditions within the above range, even if vk or vf is arbitrarily set, the toner recovery efficiency from the fur brush 17 to the recovery roller 18 is significantly reduced. Things don't happen. Further, within the above range, the collecting roller 1
The outer diameter position tangential velocity vk of 8 can be set arbitrarily. Therefore, in the above-described cleaning device 10, the photosensitive drum 1 and the collecting roller 18 as shown in FIG.
The velocity vk can be freely set to a value that can generate a powdered lubricant enough to prevent filming of the additive substance in the toner on the surface of the toner. As a result, in the cleaning device 10 of the present exemplary embodiment, the toner on the fur brush 17 is
Most of the electricity is charged by the collection roller 18 to which the bias voltage is applied.
Reliable static absorption without damaging the basic function of adsorption and recovery
The toner on the fur brush 17 can be reliably collected by the collecting roller 18, and the fur brush 17 can efficiently collect the toner on the photoconductor drum 1 for a long period of time. It is also possible to prevent filming of the additive in the toner on the surface of the drum 1 and the collecting roller 18, and by extension, the surface of the fiber forming the fur brush 17. That is, it is added to the toner used.
The added additives are collected on the surface of the photosensitive drum 1 or the like and the collecting roller
It is possible to prevent film-like adhesion on the surface of
It can be used as a solid lubricant for polishing and powdering.
Cleaning performance and eventually good image formation for a long time
You will be able to continue to earn. FIG. 7 shows the relationship between the amount of powdered lubricant produced and the change in the setting condition of the tangential velocity vk of the outer diameter position of the recovery roller 18.

Further, in this embodiment, a drive source 26 for rotating the collecting roller 18 is separately provided, and the control of the drive source 26 is obtained from an image reading system or an image data input system (not shown), for example. By setting the image area occupancy rate (in other words, toner image formation occupied area rate) per unit area to be large or small, the rotation speed of the collecting roller 18 can be made independent depending on the amount of toner used for image formation. to be able to variably control, as a result, the supply amount of the toner recovery property and powdered lubricants produced amount and the powdered lubricant in the collection roller 18 for each image forming time using the toner amount, full
Brush 17, toner discharge coil 20, or photoconductor
It depends on the rotation speed of the drum 1 and other objects to be cleaned.
It is possible to set optimal and necessary conditions at any time without
Growls 8 shows the relationship between the image occupancy ratio and the minimum required amount of the powdered lubricant for preventing filming, and FIG. 7 shows the relationship between the outer diameter position tangential velocity vk of the recovery roller 18 and the powdered lubricant generation amount. .

Further, the drive source 26 of the collecting roller 18 is controlled via the control circuit section 25 using the measurement result obtained from the temperature sensor 24 provided in the opening of the cleaning device 10 on the side of the photoconductor 1. Even if the solid lubricant 23 made of a material whose hardness changes relatively greatly depending on the ambient temperature condition is used , the temperature change of the solid lubricant may be changed in advance.
Knowing the hardness variation characteristics due to aging, each temperature, in other words, each
Solid lubricant for recovery roller rotation speed under hardness conditions
Polishing, powdered amount characteristics, that is, powdered lubricant generation amount
It is necessary for each part and each environment if the nature is understood.
The collection roller rotation speed is set according to the amount of lubricant supplied.
The speed of the recovery roller drive source can be controlled to
Preventing filming of additives inside the nas, generation of powdered lubricant
And the supply can be done in any desired manner. So how
Temperature conditions (of course, installation of the image forming device, use environment
Under a temperature condition within the limit)
Long-lasting performance and thus good image formation
It can be provided continuously. The relationship between the hardness of the solid lubricant 23 with respect to the temperature change, the relationship between the hardness of the solid lubricant 23 and the amount of powdered lubricant produced, and the relationship between the minimum required amount of the filming prevention powdered lubricant for each temperature condition are shown. These are shown in FIGS. 6, 7, and 8, respectively.

[0018]

According to the present invention, it is possible to obtain good cleaning performance and thus good image formation continuously for a long period of time.

[0019]

[0020]

[Brief description of drawings]

FIG. 1 is a cross-sectional view for explaining a main part of an image forming apparatus to which the present invention is applied and an image forming process thereof.

FIG. 2 is a schematic sectional view of a recovery roller.

FIG. 3 is a cross-sectional view showing an arrangement state of a collecting roller, a fur brush, and a solid lubricant.

FIG. 4 is a diagram showing toner recovery efficiency corresponding to a tangential speed ratio between a fur brush and a recovery roller.

FIG. 5 is a diagram showing a characteristic of a powdered lubricant production amount corresponding to a tangential velocity of a recovery roller.

FIG. 6 is a diagram showing characteristics of hardness change of a solid lubricant with respect to environmental temperature.

FIG. 7 is a diagram showing characteristics of changes in the amount of powdered lubricant produced with respect to the hardness of a solid lubricant.

FIG. 8 is a diagram showing characteristics of changes in the minimum required amount of powdered lubricant for filming prevention with respect to the amount of toner used during image formation.

[Explanation of symbols]

1 Photoconductor Drum 2 Main Charging Device 3 Exposure Optical Path 4 Developing Device 5 Paper Feeding Path 6 Transfer Paper 7 Transfer Charging Device 8 Separation Charging Device 9 Charging Device 10 Cleaning Device 11 Static Elimination Lamp 12 Transfer Paper Conveying Device 13 Fixing Device 14 Paper Ejection Section 15 cleaning blade member 16 inlet seal member 17 fur brush 18 recovery roller 18a core metal member 18b first adhesive layer 18d metal particles 18c second adhesive layer 19 scraper member 20 toner discharge coil 21 weight member 22 solid lubricant holding member 23 solid Lubricant 24 Temperature sensor 25 Control circuit section 26 Fur brush drive source 27 Solid lubricant guide section W Pressurized load by weight member and solid lubricant holding member vf Far brush outer diameter position Tangent velocity vk Recovery roller outer diameter position Tangent velocity VB Bias voltage applied to collection roller

Claims (2)

(57) [Claims] 1. A toner visible image formed on a photoreceptor,
After transferring to the transfer medium side, the toner powder remaining on the photoconductor is removed by a fur brush and a cleaning blade that are arranged in contact with the surface of the photoconductor, and the toner powder attached to the fur brush is removed. The toner is electrically adsorbed and collected by a rotating collection roller which is arranged in contact with the fur brush and to which a predetermined bias voltage is applied, and is removed from the surface of the collection roller by a scraper member which is arranged in contact with the collection roller. conveying the powder, the toner discharging coil rotates, together with the discharged, click consisting in contact with the solid lubricant additive圧当against the surface of the collection roller
In an image forming apparatus having a leaning device, a temperature for obtaining a temperature measurement result for separately providing a rotation driving source of the collecting roller and variably controlling a rotation speed setting of the rotation driving source of the collecting roller provided separately. imaging equipment, characterized in that it comprises a measuring means. 2. A toner visible image formed on a photoconductor,
After transferring to the transfer medium side, the toner powder remaining on the photoconductor is removed by a fur brush and a cleaning blade that are arranged in contact with the surface of the photoconductor, and the toner powder attached to the fur brush is removed. The toner is electrically adsorbed and collected by a rotating collection roller which is arranged in contact with the fur brush and to which a predetermined bias voltage is applied, and is removed from the surface of the collection roller by a scraper member which is arranged in contact with the collection roller. conveying the powder, the toner discharging coil rotates, together with the discharged, click consisting in contact with the solid lubricant additive圧当against the surface of the collection roller
In an image forming apparatus having a leaning device, a unit on the photoconductor is provided in order to separately provide a rotation driving source for the collecting roller and to variably control a rotation speed setting of the rotation driving source for the separately collecting roller. imaging equipment, characterized in that it comprises a means for obtaining an image occupancy ratio per area.