JP3210191B2 - Lubricant supply device to image carrier in electrophotographic apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic apparatus for forming an image on an image carrier such as a photoreceptor or a transfer belt using a toner, such as a laser copying machine, a laser printer, or a laser facsimile, and recording the image on paper. Applicable to photographic devices. More specifically, the present invention relates to a device for supplying a lubricant to an image carrier for supplying a lubricant to the surface of the image carrier in such an electrophotographic apparatus.

[0002]

2. Description of the Related Art Conventionally, for example, a lubricant supply device for a photoreceptor in a laser copying machine includes, as shown in FIG.
There is a configuration in which a solid lubricant 1 and a rotary brush 3 that rotates in contact with the lubricant 1 and the photoreceptor 2 are provided (see JP-A-56-142567).

When the laser copying machine is driven, the rotating brush 3 is rotated together with the photosensitive member 2, and the rotating brush 3 scrapes off the lubricant 1 little by little and adheres to the surface of the photosensitive member 2.

[0004]

However, in such a conventional lubricant supply device, since the solid lubricant 1 is directly rubbed with the rotating brush 3, the supply amount to the photoreceptor 2 at the initial stage, for example, is large. On the other hand, as the amount of the lubricant 1 decreases with the lapse of time, the amount of the lubricant 1 decreases and the amount of the lubricant 1 supplied to the photoreceptor 2 decreases, making it impossible to always supply an appropriate amount of the lubricant 1. There was a problem.

If the supply amount of the lubricant 1 to the photoconductor 2 becomes excessive, for example, the friction coefficient of the photoconductor 2 is reduced to a certain value or less, so that the adhesion of the toner to the photoconductor 2 is reduced, and the The image quality is deteriorated due to insufficient density, or the paper is strongly adhered to the photoconductor 2 and the paper is hard to be separated from the photoconductor 2.

On the other hand, if the amount of the lubricant supplied to the photoconductor 2 becomes too small, for example, the friction coefficient of the photoconductor 2 becomes more than a certain value, and the surface of the photoconductor 2 and the cleaning blade pressed against the photoconductor 2 are worn out and cleaned. The performance is reduced, the image quality is deteriorated, and the durability of the cleaning blade is reduced.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lubricant supply device for supplying a lubricant to an image bearing member so that a proper amount of lubricant can always be supplied.

[0008]

For this purpose, a lubricant supply device 25 for an image carrier in an electrophotographic apparatus according to the first aspect of the present invention includes a solid lubricant 30 and a solid lubricant 30 as shown in the following illustrated embodiments. The lubricant 30 is elastically pressed,
A rotating roller 29 having a center line average roughness (Ra) of 0.3 to 0.4 [mu] m, which carries a fixed amount of lubricant 30 on the peripheral surface as the rotating roller rotates; A rotating brush 26 that rotates in contact with an image carrier such as the photoconductor 11 and transfers the lubricant 30 on the rotating roller 29 to the image carrier.

In the electrophotographic apparatus according to a second aspect of the present invention, a lubricant supplying device 25 for supplying an image bearing member to a solid lubricant 30 and a pressing pressure applied to the lubricant 30 are provided as shown in the following embodiments. 0.2 to 0.4 N / cm ²
A rotating roller 29 which carries a certain amount of lubricant 30 on the peripheral surface as it rotates, the rotating roller 29 and the photosensitive member 11
A rotating brush 26 that rotates in contact with the image carrier and transfers the lubricant 30 on the rotating roller 29 to the image carrier.

According to a third aspect of the present invention, there is provided an electrophotographic apparatus according to the first or second aspect of the present invention, as shown in FIG. Roller 29 and rotating brush 2
6 in contact with each other in opposite directions and at the same linear velocity at their contact portions.

[0011]

When the electrophotographic apparatus is driven, the rotating roller 29 and the rotating brush 26 are rotated together with the image bearing member, and come into contact with the solid lubricant 30 so that a fixed amount of the rotating roller 29 contacts the peripheral surface of the rotating roller 29. A lubricant is carried and the lubricant 30 carried on the rotating roller 29 is transferred onto the image carrier by the rotating brush 26.

According to the third aspect of the present invention, when the electrophotographic apparatus is driven, the rotating roller 29 and the rotating brush 26 come into contact with each other at their contact portions in opposite directions and at the same linear velocity.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 8 shows a schematic configuration of a recording section R of a laser printer provided with a device for supplying a lubricant to an image carrier according to the present invention.

The recording section R is provided with a drum-shaped photosensitive member 11 as an image carrier. Around the photosensitive member 11, a charging device 12, a developing device 13, a transfer charger 14, a separation charger 15, a cleaning device 16, and a charge removing device 17 are arranged in a driving direction indicated by an arrow in the drawing. Also,
An optical writing device 18 is provided above the photoconductor 11.

At the time of recording, the paper P is sent out from a paper supply unit (not shown), and is conveyed to the lower side of the photoconductor 11 at a timing by a pair of registration rollers.

The photoreceptor 11 is driven to rotate clockwise as indicated by an arrow. At this time, the surface of the photoreceptor 11 is uniformly charged by the charging device 12, and the surface is irradiated with laser light from the optical writing device 18 to expose the photoreceptor. An electrostatic latent image is formed on the body 11.

Next, after the unnecessary charge in the non-image area on the photoconductor 11 is removed by the eraser 19, the electrostatic latent image on the photoconductor 11 is removed by the toner when passing the developing device 13. Visualize.

Then, the visible image is transferred by the transfer device 14 onto the upper surface of the sheet P conveyed below the photoconductor 11. After the transfer, the sheet P is separated from the photoreceptor 11 by removing electricity from the separation charger 15.

After the separation, the sheet P is conveyed to a fixing device (not shown), where the transferred image is fixed and then discharged outside.

On the other hand, after the image transfer, the photosensitive member 11 removes the residual toner from the cleaning blade 2 of the cleaning device 16.
0, and then the static elimination charger 2 of the static elimination device 17
In step 1, the charge is removed, and the charge is radiated by the discharge lamp 22 to initialize electrostatically, to prepare for the next use.

FIG. 1 is a schematic view of a lubricant supply device 25 for supplying a photosensitive member, which is an embodiment provided in the above-mentioned laser copying machine. The lubricant supply device 25 is disposed downstream of the cleaning blade 20 in the rotation direction of the photoconductor 11.

The lubricant supply device 25 includes a rotating brush 26. The rotating brush 26 is formed by implanting a plurality of brush-shaped polyester fibers 28 having a bristle length of 6 mm on the outer periphery of an aluminum cylindrical member 27 having a diameter of 13 mm in a brush shape, and has a diameter of 25 mm. . Then, both ends are rotatably supported as appropriate and arranged in parallel with the photoreceptor 11, and in a state where the tip of the polyester fiber 28 is in contact with the surface of the photoreceptor 11, the driving means (not shown) rotates clockwise as indicated by an arrow. Provide freely.

In the vicinity of the rotating brush 26, a rotating roller is provided.
２９29 is provided. The rotating roller 29 has a diameter of 16 mm.
A roller made of stainless steel having a surface roughness of, for example, a center line average roughness (Ra) of 0.
It becomes 3 to 0.4 μm. Then, both ends are rotatably supported as appropriate and arranged in parallel with the rotating brush 26, and with the end of the polyester fiber 28 in contact with the peripheral surface of the rotating roller 29, an arrow is indicated by driving means (not shown). To be rotatable clockwise.

The tip of a lubricant 30 is provided on the outer periphery of the rotary roller 29 by pressing. The lubricant 30
Is obtained by melting a material containing zinc stearate as a main component, solidifying it by cooling, and forming it into a horizontally long plate shape, and appropriately supporting both ends.

Then, one end of a compression spring 31 is pressed against the base end of the lubricant 30. The compression spring 31 has the other end pressed against an appropriate position, and elastically presses the lubricant 30 against the rotary roller 29.

When the laser copying machine is driven, the rotating roller 29 and the rotating brush 26 are rotated together with the photoreceptor 11 and come into contact with the solid lubricant 30 so that a predetermined amount is formed on the peripheral surface of the rotating roller 29. Of the lubricant 30. Then, the lubricant 30 carried on the rotating roller 29 is applied to the rotating brush 26.
Is uniformly transferred onto the photoconductor 11 by the rotation of.

When the surface roughness of the rotating roller 29 is large, the amount of the lubricant carried on the rotating roller 29 increases, and the amount of the lubricant 30 supplied to the photoconductor 11 becomes excessive.
Then, as shown in FIG.
The sheet P is strongly adhered to the sheet 1 and the sheet P is hard to be separated from the photoconductor 11. Therefore, looking at the surface roughness of the rotating roller 29 corresponding to a certain value, the center line average roughness (Ra) is equal to 0.
4 μm. Then, as is clear from this figure,
The surface roughness of the rotating roller 29 is determined by the center line average roughness (Ra).
Since the thickness is set to 0.4 μm or less, the rotating roller 29 is always used.
A suitable amount of the lubricant 30 can be carried on the peripheral surface of. Accordingly, it is possible to prevent the supply amount of the lubricant 30 to the photoconductor 11 from becoming excessive, and to ensure the separation property of the paper P.

On the other hand, if the surface roughness of the rotating roller 29 is small, the amount of the lubricant carried on the rotating roller 29 becomes small, and the amount of the lubricant 30 supplied to the photoreceptor 11 becomes too small.
Then, as shown in FIG. 3, when the value is less than a certain value, the surface of the photoconductor 11 and the cleaning blade 20 pressed against the photoconductor 11 are worn, and the cleaning performance is reduced. Therefore,
Looking at the surface roughness of the rotary roller 29 corresponding to a certain value,
The center line average roughness (Ra) is 0.3 μm. Then
As is apparent from this figure, since the surface roughness of the rotating roller 29 is not less than the center line average roughness (Ra) of 0.3 μm, an appropriate amount of the lubricant 30 is always applied to the peripheral surface of the rotating roller 29. Can be carried. Accordingly, it is possible to prevent the supply amount of the lubricant 30 to the photoconductor 11 from being excessively small, and to secure the cleaning performance.

In the illustrated embodiment, the surface roughness of the rotary roller 29 is taken into consideration, and the surface roughness is set to a center line average roughness (Ra) of 0.3 to 0.4 μm.
However, in consideration of the pressing pressure of the lubricant 30 against the rotating roller 29, the pressing pressure may be set to 0.2 to 0.4 N / cm ² .

When the laser copying machine is driven, the rotating roller 29 and the rotating brush 26 are rotated together with the photoreceptor 11 and come into contact with the solid lubricant 30 to make a certain amount of contact with the peripheral surface of the rotating roller 29. Of the lubricant 30. Then, the lubricant 30 carried on the rotating roller 29 is applied to the rotating brush 26.
Is uniformly transferred onto the photoconductor 11 by the rotation of.

Generally, when the pressing pressure of the lubricant 30 against the rotating roller 29 is large, the amount of the lubricant carried on the rotating roller 29 increases, and the lubricant 3
The supply amount of 0 becomes excessive. And, as shown in FIG.
If the value exceeds a certain value, the paper P is strongly adhered to the photoconductor 11 and the paper P is hard to be separated from the photoconductor 11. Then, looking at the pressing pressure corresponding to a certain value, it is 0.4 N / cm ² . Thus, as is apparent from this figure, since the pressing pressure is set to 0.4 N / cm ² or less, a suitable amount of the lubricant 30 can be always carried on the peripheral surface of the rotating roller 29. As a result, it is possible to prevent the supply amount of the lubricant 30 to the photoconductor 11 from being excessive, and to ensure the sheet separation.

On the other hand, the lubricant 30 for the rotating roller 29
Is small, the amount of the lubricant carried on the rotating roller 29 becomes small, and the amount of the lubricant 30 supplied to the photoreceptor 11 becomes too small. As shown in FIG. 5, when the value is less than a certain value, the surface of the photoconductor 11 and the cleaning blade 20 pressed against the photoconductor 11 are worn and the cleaning performance is reduced. Then, when the pressing pressure of the rotary roller 29 corresponding to a certain point is seen, it is 0.2 N / cm ² . Thus, as is apparent from this figure, the pressing pressure is set to 0.2 N / cm ² or more, so that an appropriate amount of the lubricant 30 can be always carried on the peripheral surface of the rotating roller 29. Thereby, the photosensitive member 1
To prevent the supply amount of the lubricant 30 to 1 from becoming too small,
Cleaning performance can be ensured.

In the above-described laser copying machine, a small amount of the lubricant 30 adheres to the collected toner when the cleaning blade 20 removes the residual toner on the photosensitive member 11 during cleaning. Therefore, even with the collected toner, the fluidity does not decrease, and high fluidity is maintained. Thus, it is possible to prevent the collected toner from being stagnated or fixed in the conveyance path of the collected toner.

In general, when the linear speed of the rotating brush 26 is higher than the linear speed of the rotating roller 29 in the directions opposite to each other at the contact portion between the rotating roller 29 and the rotating brush 26, as shown in FIG. As shown in (1), the amount of transfer of the lubricant 30 from the rotating roller 29 to the rotating brush is reduced, so that the rotating roller 29 preferably rotates faster. However, when the linear speed of the rotating roller 29 is increased, the rotating brush 26 is deteriorated, for example, the hair falls or breaks, as shown in FIG.
Therefore, as is apparent from FIG. 6, the rotating roller 29 and the rotating brush 2 corresponding to the best value of the transfer amount of the lubricant 30 are used.
Looking at the linear velocity of No. 6, it is the same.

Therefore, in the lubricant supply device 25 of the illustrated embodiment, the rotary brush 26 and the rotary roller 29
It is preferable that the contact portions contact each other in opposite directions and at the same linear velocity. As described above, since the rotating roller 29 has a diameter of 16 mm and the rotating brush 26 has a diameter of 25 mm, for example,
The rotating speed of the rotating brush 26 is set to 200 rpm,
Assuming that the rotation speed of the la 29 is 156 rpm, the rotating brush 2
The linear velocity of No. 6 is 25 × π × 200 × 1/60 = 131 mm
/ Sec, while the linear velocity of the rotating roller 29 is 16 × π
X 156 x 1/60 = 131 mm / sec.

From this, as shown in FIG. 6, the lubricant 30 is efficiently transferred from the rotating roller 29 to the rotating brush 26 without increasing the linear speed of the rotating roller 29 and deteriorating the rotating brush 26. Can be transferred well.

As the lubricant 30, besides the zinc stearate, barium stearate, lead stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, calcium stearate, stearin Cadmium acid, magnesium stearate, zinc oleate,
Manganese oleate, Iron oleate, Cobalt oleate, Lead oleate, Magnesium oleate, Copper oleate, Palmitic acid, Zinc cobalt palmitate, Copper palmitate, Magnesium palmitate, Aluminum palmitate, Calcium palmitate, Cabrylic acid Relatively higher fatty acids such as lead, lead caproate, zinc linolenate, cobalt linolenate, calcium linolenate, cadmium coronenonate can be used. Further, colloidal high-temperature silica powder can be used, and further, natural wax such as carnauba wax can be used.

Further, in the laser copying machine of the illustrated embodiment, an example is shown in which a photoconductor 11 for transferring an image to a sheet P is used as an image carrier. However, although not shown, a color laser for sequentially transferring images formed on the photoreceptor to a transfer belt to form a color image on the transfer belt, and transferring the color image at a time to form an image on paper In a copying machine, an intermediate transfer member such as an intermediate transfer belt may be used.

[0039]

According to the first aspect of the present invention, the surface roughness of the rotary roller against which the lubricant is pressed is set to the center line average roughness (Ra) of 0.3 to 0.4 μm. Therefore, according to the second aspect, the pressing pressure is 0.2 to 0.2.
Since the lubricant is pressed against the rotating roller at 4 N / cm ² ,
An appropriate amount of lubricant can always be carried on the rotating roller. Therefore, an appropriate amount of lubricant can be transferred to the image carrier by the rotation of the rotating brush, and for example, occurrence of insufficient image density, poor separation of paper from the image carrier, deterioration of cleaning performance, and the like can be prevented.

According to the third aspect of the present invention, the rotating roller
The contact between the roller and the rotating brush is in opposite directions and at the same linear velocity, so that the linear velocity of the rotating roller can be increased to efficiently transfer the lubricant without deteriorating the rotating brush. it can.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for supplying a lubricant to an image carrier according to an embodiment of the present invention.

FIG. 2 is a graph showing the relationship between the surface roughness and the separability, with the surface roughness of the rotating roller being plotted on the abscissa and the separability of the paper from the photosensitive member being plotted on the ordinate.

FIG. 3 is a graph showing the relationship between the surface roughness and cleaning performance.

FIG. 4 is a graph showing the relationship between the pressing pressure and the separability, with the horizontal axis representing the pressing pressure of the lubricant pressed against the rotating roller and the vertical axis representing the separation of the paper from the photosensitive member.

FIG. 5 is a graph showing the relationship between the pressing pressure and the cleaning performance.

FIG. 6 is a graph showing the relationship between the linear velocity and the amount of lubricant transfer with the horizontal axis representing the relationship between the linear velocity at the contact portion of the rotating roller and the rotary brush and the vertical axis representing the amount of lubricant transfer.

FIG. 7 is a graph showing the relationship between the linear speed of the rotating roller and the deterioration of the rotating brush, with the linear speed of the rotating roller on the horizontal axis and the deterioration of the rotating brush on the vertical axis.

8 is a schematic configuration diagram of a recording unit of a laser copying machine including the device for supplying a lubricant to the image carrier shown in FIG.

FIG. 9 is a schematic configuration diagram of a conventional apparatus for supplying a lubricant to an image carrier.

[Explanation of symbols]

 25 Lubricant supply device 26 Rotary brush 29 Rotary roller 30 Lubricant

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G03G 21/00 G03G 21/10-21/12

Claims (3)

(57) [Claims] 1. A solid lubricant, which is elastically pressed against the lubricant and carries a certain amount of lubricant on the peripheral surface with rotation. The surface roughness has a center line average roughness (Ra) of 0.3. A rotating roller having a thickness of about 0.4 μm, a rotating brush rotating in contact with the rotating roller and the image carrier, and transferring a lubricant on the rotating roller to the image carrier; A lubricant supply device for an image carrier in an electrophotographic apparatus, comprising: 2. A solid lubricant, and a rotary roller against which the lubricant is pressed at a pressing pressure of 0.2 to 0.4 N / cm ^{2, and} which carries a certain amount of lubricant on the peripheral surface as it rotates. And a rotating brush that rotates in contact with the rotating roller and the image carrier, respectively, and transfers a lubricant on the rotating roller to the image carrier. An image carrier in an electrophotographic apparatus, comprising: Lubrication supply device to the. 3. An image in an electrophotographic apparatus according to claim 1, wherein said rotating roller and said rotating brush are contacted at their contact portions in mutually opposite directions and at the same linear velocity. A device for supplying lubricant to the carrier.