JP2000187409A - Releasing agent supplying device for fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently filter a releasing agent by using the entire surface of a filter for the filtering of the releasing agent by gradually filtering by making the releasing agent supplied on the filter of a filtering part flow in a first flow passage on the filter to the other end side. SOLUTION: The filtering part 309 is supported in a state where a lower space is formed between a filtering filter 309c and the bottom surface of a housing 309a which is a housing provided so as to be freely attachable/ detachable by plural supporting parts 309b at the inside of the housing 309a. The filtering filter 309c is supported to be inclined in a horizontal direction so that one end side supplied with silicone oil from a recovery pipe 308 is set high so as to be an upstream side in a direction in which the silicone oil flows and the other end side is set low so as to be a downstream side, and an upper space between the filtering filter 309c and the upper surface of the housing 309a is set to be the first flow passage so that the silicone oil fed on the filtering filter 309c flows from the upstream side to the downstream side and the lower space is set to be the second flow passage of the silicone oil that is filtered by passing through the filter 309c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a release agent for a fixing device which supplies a release agent (silicone oil) to the surface of the fixing roller in order to prevent an offset at the fixing roller of the fixing device in the image forming apparatus. The present invention relates to a supply device.

[0002]

2. Description of the Related Art Conventionally, in a fixing device of an image forming apparatus in an electrophotographic process, generally, a transfer material on which a toner image has been transferred is guided between a pair of pressure-contacted fixing rollers.
By passing between the fixing rollers, the toner image transferred onto the transfer material is fixed on the transfer material.

At this time, an offset occurs due to the toner melted in the fixing roller, and the transfer material is wound around the fixing roller, resulting in poor conveyance of the transfer material, which hinders the subsequent image formation. A method has been used in which a releasing agent such as silicone oil is applied to the surface and the melted toner is easily separated.

For applying silicone oil to the surface of the fixing roller, there has been a method in which a supply roller impregnated with silicone oil is brought into contact with the surface of the fixing roller, and the silicone oil is applied to the surface of the fixing roller so as to apply an appropriate amount of silicone oil. .

In the application of silicone oil using the supply roller, in an image forming apparatus which has been advanced in speed and color as in recent years, the supply roller impregnated with silicon oil is brought into contact with the surface of the fixing roller. It is difficult to stably supply silicone oil to the surface of the fixing roller only by performing the above operation.

Accordingly, silicon oil is supplied to the supply roller to apply and supply the silicon oil to the surface of the fixing roller, and the excess silicon oil on the surface of the fixing roller is recovered, and the recovered silicon oil is supplied to the supply roller again. Thus, there is a circulation supply type in which silicon oil is circulated.

In this circulating supply system, impurities such as paper dust, toner and dust are mixed in excess silicon oil, and when the recovered silicon oil is circulated and reused, the silicon oil gradually becomes contaminated. To cause uneven coating of silicone oil and decrease in releasability.
Install a filter in the circulation path of the recovered silicone oil,
Some filters remove impurities contained in the silicon oil and resupply them.

Japanese Unexamined Patent Publication No. Hei 6-250 proposes that the filter removes impurities and resupplies silicon oil.
No. 556 has been described. This Japanese Patent Laid-Open No. 6
Japanese Patent Application Laid-Open No. 250556/1999 has provided a filter in a container for storing the recovered silicon oil.

This filter has a bag-shaped filter disposed in silicon oil stored in a container, and the collected silicone oil flows into the bag-shaped filter to remove impurities. There is a type in which a sheet-shaped filter is disposed horizontally, and the recovered silicon oil is supplied onto the sheet-shaped filter, and the silicon oil which has passed through the filter and from which impurities have been removed is stored.

[0010]

However, in the case of using a bag-shaped filter, since the filter is immersed in the collected and stored silicone oil, it is difficult to replace only the filter when replacing the filter. there were.

In the case where the sheet-like filter is disposed horizontally, impurities are filtered by passing the recovered silicon oil through the filter in the vertical direction by its own weight, so that only a part of the filter is used. When this portion is clogged with impurities removed from the silicon oil, it is difficult for the silicon oil to flow on the filter surface, and it is difficult for the other portions to be filtered.
The entire filter could not be used effectively.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a release agent supply device for a transfer device according to the present invention rotates a toner image transferred onto a transfer material. A release agent supply unit that supplies a toner release agent to the surface of a fixing roller of a fixing device that fixes by a pair of rollers, and a surplus release agent applied to the fixing roller by a release agent application unit is collected. A collecting section, a filtering section having a filter for filtering impurities contained in the release agent collected by the collecting section, a storage section for storing the release agent filtered by the filtering section, and a storage section for storing the release agent. A re-supplying unit for supplying the released release agent to the release agent supply unit again, and a recovered release agent supply unit for supplying the released release agent onto one end of the filter of the filtration unit is provided. The above-mentioned filtration unit is configured such that the release agent supplied by the recovered release agent supply unit is a filter. A first flow path of the release agent to flow to the other end side transmitted to and forms a second flow path that flows through the release agent after being passed through the filter filtration.

According to a second aspect of the present invention, the filtration unit of the releasing agent supply device of the fixing device includes a housing and a releasing agent that flows from one end side, which is upstream in the horizontal direction, to the other end, which is downstream in the housing. A filter disposed at an angle from one end to the other end so as to generate a flow, a first flow path having an upper space of the housing partitioned by the filter as a flow path, and a lower portion of the housing partitioned by the filter A second flow path having a space as a flow path.

According to a third aspect of the present invention, there is provided a release agent supply device for a fixing device, wherein a filtered release agent is supplied to a storage section at a second end downstream of the second flow path of the filtration section. A supply port is provided.

According to a fourth aspect of the present invention, the first flow path and the second flow path of the filtration unit are provided along the width direction of the transfer material of the fixing device.

According to a fifth aspect of the present invention, the filter of the releasing agent supply device of the fixing device is detachably formed.

According to a sixth aspect of the present invention, there is provided a release agent supplying device for a fixing device, wherein a gap through which the release agent passes is provided between the filter and the filter at least on the downstream side of the first flow path.

According to a seventh aspect of the present invention, there is provided a release agent supplying device for a fixing device, wherein the toner image transferred onto the transfer material is fixed by a pair of rotating rollers. A release agent supply unit that supplies the release agent, a collection unit that collects an excess of the release agent applied to the fixing roller by the release agent application unit, and an impurity contained in the release agent collected by the collection unit. A filtration unit having a filter for filtering, a storage unit for storing the release agent filtered by the filtration unit, and a re-supply unit for re-supplying the release agent stored in the storage unit to the release agent supply unit. A collecting release agent supply section for supplying the collected release agent onto one end side of the filter of the filtration section; and the filtering section is configured to filter the release agent supplied by the collected release agent supply section. A first flow path of the release agent flowing on the other end side,
A second flow path through which the release agent flows after passing through the filter and is filtered is formed, and the filtering ability of the release agent is different between the upstream side and the downstream side of the filter.

The filter of the releasing agent supply device of the fixing device according to the present invention is arranged such that the upstream side has a first filtering area having a high filtering ability for the releasing agent, and the downstream side has a first filtering area having a filtering ability for the releasing agent. It is formed in the second filtration area lower than the area.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a digital color copying machine which is an image forming apparatus of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing the configuration of a digital color copying machine.

Copying machine body 1 of this digital color copying machine
The document table 111 and an operation panel (not shown)
Is provided, and an image reading unit 110 and an image forming unit 210 are provided inside the copying machine main body 1.

On the upper surface of the platen 111, the platen 111
The document is supported so that it can be opened and closed, and has a predetermined positional relationship with respect to the surface of the document table 111 (RADF: Recirculating Auto Document Document Fe).
eder) 112 is mounted.

Further, the RADF 112 first conveys the document so that one side of the document faces the image reading unit 110 at a predetermined position on the document table 111, and after reading the image on one side, the other side. The document is inverted and transported toward the document table 111 such that the surface of the document faces the image reading unit 110 at a predetermined position on the document table 111. Then, the RADF 112 discharges this document after reading the image on both sides of one document, and executes the duplex conveyance operation for the next document. The above-described document conveyance and reverse operation are controlled in relation to the operation of the entire copying machine.

The image reading section 110 is arranged below the document table 111 for reading an image of a document conveyed onto the document table 111 by the RADF 112. The image reading unit 110 includes original scanning bodies 113 and 114 that reciprocate in parallel along the lower surface of the original table 111, an optical lens 115, and a CCD line sensor 11 that is a photoelectric conversion element.
6.

The original scanning bodies 113 and 114 are composed of a first scanning unit 113 and a second scanning unit 114. The first scanning unit 113 has an exposure lamp for exposing the surface of the document image, and a first mirror for deflecting a reflected light image from the document in a predetermined direction.
1 is reciprocally moved in parallel at a predetermined scanning speed while maintaining a constant distance from the lower surface of the light-emitting device 1. The second scanning unit 114 has second and third mirrors for further deflecting the reflected light image from the document deflected by the first mirror of the first scanning unit 113 in a predetermined direction, and the first scanning unit It reciprocates in parallel with 113 while maintaining a constant speed relationship.

The optical lens 115 is connected to the second scanning unit 1
The reflected light image from the document deflected by the third mirror 14 is reduced, and the reduced light image is converted to a CCD line sensor 116.
An image is formed at the upper predetermined position.

The CCD line sensor 116 sequentially converts the formed light images into photoelectric signals and outputs them as electric signals. The CCD line sensor 116 is a three-line color CCD capable of reading a black-and-white image or a color image and outputting line data separated into R (red), G (green), and B (blue) color components. . The document image information converted into an electric signal by the CCD line sensor 116 is further transferred to an image processing unit (not shown) and subjected to predetermined image data processing.

Next, the configuration of the image forming unit 210 and the configuration of each unit related to the image forming unit 210 will be described.

Below the image forming section 210, there is provided a sheet feeding mechanism 211 for separating the sheets (recording media) P stored in the sheet feeding cassette one by one and supplying the separated sheets P toward the image forming section 210. Have been. Then, the sheets P separated and supplied one by one are conveyed to the image forming unit 210 at a controlled timing by a pair of registration rollers 212 disposed in front of the image forming unit 210. Further, the sheet P on which an image is formed on one side is re-supplied and conveyed to the image forming unit 210 in synchronization with the image formation of the image forming unit 210. A transfer / conveyance belt mechanism 213 is disposed below the image forming unit 210. The transfer / transport belt mechanism 213 includes a transfer / transport belt 21 stretched between the drive roller 214 and the driven roller 215 so as to extend substantially in parallel.
6, the paper P is electrostatically attracted and transported. Then, in the vicinity of the lower side of the transfer conveyance belt 216,
A pattern image detection unit is provided.

Further, a fixing device 21 for fixing the toner image transferred and formed on the sheet P on the sheet P is provided downstream of the transfer and conveyance belt mechanism 213 in the sheet conveyance path.
7 are arranged. The paper P that has passed through the nip between the pair of fixing rollers of the fixing device 217 passes through a conveyance direction switching gate 218 and is discharged by discharge rollers 219 onto a paper discharge tray 220 attached to the outer wall of the copying machine main body 1. You.

The switching gate 218 switches the conveyance path of the sheet P after fixing between the path for discharging the sheet P to the copying machine main body 1 and the path for re-supplying the sheet P to the image forming section 210. It is selectively switched. The sheet P whose transport direction has been switched again toward the image forming unit 210 by the switching gate 218 is turned upside down via the switchback transport path 221, and then the image forming unit 21.
0 again.

Further, above the transfer belt 216 in the image forming section 210, the first image forming station Pa, the second image forming station Pb, the third image forming station Pc, The fourth image forming stations Pd are arranged in order from the upstream side of the sheet transport path.

The transfer conveyance belt 216 is driven by a driving roller 214.
As a result, the sheet P is frictionally driven in the direction indicated by the arrow Z in FIG. 1 and is fed through the sheet feeding mechanism 211 as described above.
Conveyed sequentially to Pd.

Each of the image forming stations Pa to Pd has substantially the same configuration. Each of the image forming stations Pa, Pb, Pc, and Pd is a photosensitive drum 222a, 222b, or 22 that is driven to rotate in the direction of arrow F shown in FIG.
2c and 222d, respectively.

Around the photosensitive drums 222a to 222d, chargers 223a, 223b, 223c, 223d for uniformly charging the photosensitive drums 222a to 222d, respectively.
And developing devices 224a, 224b, and 2 for developing the electrostatic latent images formed on the photosensitive drums 222a to 222d, respectively.
24c, 224d and the developed photosensitive drum 222a
And discharge devices 225a, 225b, 225c, 225d for transferring the toner images on the sheets P to 222d, and cleaning devices 226a, 226b, 226c, 22 for removing the toner remaining on the photosensitive drums 222a to 222d.
6d are sequentially arranged along the rotation direction of the photosensitive drums 222a to 222d.

Each of the photosensitive drums 222a to 222d
Above the laser beam scanner unit 227
a, 227b, 227c, and 227d are provided respectively. Laser beam scanner units 227a to 227
d is a semiconductor laser device (not shown) that emits dot light modulated according to image data, a polygon mirror (deflecting device) 240 for deflecting a laser beam from the semiconductor laser device in the main scanning direction, Polygon mirror 2
The laser beam deflected by 40 is transferred to the photosensitive drum 2
Fθ lens 2 for forming an image on the surface of 22a to 222d
41, and mirrors 242, 243 and the like.

Laser beam scanner unit 227a
Is a pixel signal corresponding to a black component image of a color original image, a laser beam scanner unit 227b is a pixel signal corresponding to a cyan component image of a color original image, and a laser beam scanner unit 227c is a magenta image of a color original image. A pixel signal is input to the color component image, and a pixel signal corresponding to the yellow component image of the color original image is input to the laser beam scanner unit 227d.

As a result, the electrostatic latent images corresponding to the color-converted original image information are formed on the photosensitive drums 222a to 222d.
Formed on top. The developing device 224a includes the black toner, the developing device 224b includes the cyan toner,
The developing device 224c contains magenta toner, and the developing device 224d contains yellow toner. The electrostatic latent images on the photosensitive drums 222a to 222d are:
The image is developed with the toner of each color. As a result, the document image information color-converted by the image forming unit 210 is reproduced as a toner image of each color.

Further, between the first image forming station Pa and the paper feeding mechanism 211, a paper suction charger (brush) 2 is provided.
The paper suction charger 228 charges the surface of the transfer conveyance belt 216,
The sheet P supplied from the first image forming station Pa is securely sucked onto the transfer conveyance belt 216 in the first image forming station Pa.
To the fourth image forming station Pd without shifting.

On the other hand, a static eliminator 229 is provided almost directly above the drive roller 214 between the fourth image forming station Pd and the fixing device 217. An alternating current for separating the paper P electrostatically attracted to the transfer / transport belt 216 from the transfer / transport belt 216 is applied to the neutralizer 229.

In the digital color copying machine having the above configuration, cut sheet-shaped paper is used as the paper P. The sheet P is sent out from the sheet cassette and fed to the sheet feeding mechanism 2.
11, the leading end of the sheet P is detected by a sensor (not shown), and based on a detection signal output from the sensor, the pair of registration rollers 212 Once stopped.

Then, the paper P is fed onto the transfer / conveying belt 216 rotating in the direction of arrow Z in FIG. 1 at the timing of each of the image forming stations Pa to Pd. At this time, since the transfer conveyor belt 216 has been given a predetermined charge by the paper suction charger 228 as described above,
The sheet P is stably conveyed and supplied while passing through the image forming stations Pa to Pd.

In each of the image forming stations Pa to Pd, a toner image of each color is formed, and is superposed on the support surface of the paper P conveyed by being electrostatically attracted by the transfer conveyance belt 216. When the transfer of the image by the fourth image forming station Pd is completed, the sheet P is sequentially peeled off the transfer / conveying belt 216 from the leading end thereof by the static eliminator 229 and guided to the fixing device 217. Finally, the sheet P on which the toner image has been fixed is discharged into a sheet discharge port (not shown).
Is discharged onto the discharge tray 220 from the paper tray.

In the above description, the laser beam is scanned and exposed by the laser beam scanner units 227a to 227d, whereby the photosensitive drum 2 is exposed.
Writing to 22a to 222d is performed. However, instead of the laser beam scanning unit, a writing optical system (LE) composed of a light emitting diode array and an imaging lens array is used.
D head). The LED head is smaller in size than the laser beam scanning unit, has no moving parts, and is silent. Therefore, it can be suitably used in an image forming apparatus such as a tandem type digital color copying machine which requires a plurality of optical writing units.

Next, a first embodiment of a release agent (silicone oil) supply device for a fixing device, which is a characteristic portion of the present invention, will be described with reference to FIGS.

As shown in FIG. 1, a fixing device 217 for fixing the toner image transferred onto the sheet P is disposed downstream of the image forming section 210 of the copying machine main body 1. 2 and 3 show the configuration of the fixing device 217 in detail. FIG. 2 is a perspective view of the fixing device 217, and FIG. 3 is a sectional view of the fixing device 217.

The fixing device 217 is provided with a pair of upper and lower fixing rollers 300 and 301 in pressure contact with each other. Around the fixing roller 300, an upper cleaning member for cleaning the surface of the fixing roller 300 is provided. A roller 302;
An application roller 303 for applying a release agent, for example, silicone oil, to the surface of the cleaned fixing roller 300 is disposed downstream of the upper cleaning roller 302.

Above the application roller 303, a felt 3 for applying and supplying silicone oil to the application roller 303 is provided.
An oil supply pipe 304 for supplying silicon oil is disposed on the surface of the application roller 303, a felt 306 for applying silicon oil to the surface of the application roller 303, and an application roller for scraping excess silicon oil. Blades 305 for uniformly applying silicone oil over the entire surface of the surface 303 are in contact with each other.

The silicon oil applying means is constituted by these members, and the excess silicon oil scraped off by the blade 305 is received by an oil receiving portion 307, and the oil receiving portion 307 is fixed to the fixing device 21.
7 is provided along the width direction of the sheet P to be fixed, that is, along the axial direction of the fixing rollers 300 and 301, and collects silicon oil at one end thereof. This silicone oil is provided at one end of the oil receiving portion 307. Recovery pipe 30
8 to the filtration unit 309.

The filtration unit 309 is provided with fixing rollers 300 and 3
The filter has a filtration filter 309c provided along the axial direction (longitudinal direction) of No. 01, and silicon oil is sent from the recovery pipe 308 to one end on the filtration filter 309c.

Here, the silicon oil sent onto the filter 309c contains impurities such as paper dust, toner, and dust, and the silicon oil is filtered to remove impurities by passing through the filter 309c. The silicon oil is dropped and collected into an oil tank 310 that stores the silicon oil, and an appropriate amount of the silicon oil is supplied from the oil tank 310 to a felt 306 via an oil supply pipe 304 by a pump 311.

The structure of the filtering section 309 will be described with reference to FIG.

The filtering section 309 is provided in a housing 309a which is a detachably provided housing.
9c is a housing 309a by a plurality of support portions 309b.
Is supported in a state where a lower space is formed between the lower space and the bottom surface. The filtration filter 309c is supported in such a manner that one end where silicon oil is sent from the recovery pipe 308 in the horizontal direction is high so that it is upstream in the direction in which the silicon oil flows, and the other end is low and low so that it is downstream. The silicon oil sent on the filtration filter 309c is changed from the upstream side (one end side, left side in FIG. 4) to the downstream side (other end side, right side in FIG. 4).
Filter 309c and housing 309 to flow to
The upper space between the upper surface and the upper surface of FIG. a is defined as a first flow path, and the lower space is defined as a second flow path of the silicon oil that has passed through the filter 309c and has been filtered.

A recovery port 309d for dropping and collecting the silicon oil filtered by the filter 309c to the oil tank 310 is provided on the downstream side of the bottom surface of the housing 309a.
Is provided.

When silicon oil containing impurities is sent to the upstream side of the filtration filter 309c of the filtration unit 309 configured as described above, the silicon oil is gradually filtered while flowing downstream through the filtration filter 309c. Silicon oil from which impurities have been filtered through the filter 309c flows out to the second flow path, flows on the bottom surface of the housing 309a, and is collected from the collection port 309d to the oil tank 310.

As described above, the filtration filter 309c can filter the silicon oil on the upstream side without clogging at first, and the silicon oil filtered on the upstream side can be used as the second flow in the lower space. The oil flows out into the passage, flows through the second passage, and is collected in the oil tank 310.

When the amount of filtration on the upstream side of the filter 309c increases during continuous use, the amount of impurities removed from the silicon oil increases,
When the impurities cause the upstream side of the filtration filter 309c to be clogged and the filtration efficiency is reduced, the filtration filter 309c is supported with an inclination, so that the silicon oil is deposited on the surface of the filtration filter 309c (first flow path). Flows from the upstream side to the downstream side without delay on the surface of the filtration filter 309c, and is filtered at a non-clogged portion on the downstream side of the filtration filter 309c to collect silicon oil from which impurities have been removed.

As described above, the silicon oil sent from the recovery pipe 308 onto the filtration filter 309c is
Since it flows without stagnation from the upstream side to the downstream side in the longitudinal direction of the filtration filter 309c and is gradually filtered and collected, the silicon oil can be efficiently filtered using the entire filtration filter 309c.

When the overall filtration performance of the filter 309c is reduced, the housing 309a can be periodically removed and replaced with a new filter 309, and the filter 309c can be easily replaced. .

Next, the filtering section 309 of the second embodiment of the releasing agent (silicone oil) supply device of the fixing device, which is a characteristic portion of the present invention, will be described with reference to FIG.

The filtering section 309 has the same basic structure as that of the first embodiment, and includes a housing 309a, a filtering filter 309c, a support section 309b, and a collection port 30.
9d, and a filter S 309c is provided by forming a gap S between the inner surface of the housing 309a and the filter 309c.

When the filtration filter 309c is used for a long time or when the amount of impurities filtered during the replacement period of the filtration unit 309 is very large (the amount of impurities contained in the recovered silicon oil differs depending on the environment in which the copying machine is used). 2), the entire surface of the filter 309c is clogged, the amount of silicon oil passing through the filter 309c is extremely reduced, and the amount of silicon oil passing therethrough is increased, and the amount of silicon oil passing through the surface of the filter 309c is increased. Even if the oil accumulates and the amount of silicon oil accumulated on the surface increases, the silicon oil passes through the clearance S between the filter 309c and the housing 309a.
The liquid flows down to the second flow path in the space below c, and is collected into the oil tank 310 from the collection port 309d.

Therefore, the amount of silicon oil accumulated on the surface of the filter 309c increases, and
09a (from the recovery pipe 308 to the housing 3).
09a) to prevent silicon oil from overflowing out of the filtration unit 309 from the portion where silicon oil is sent into the filter portion 309, and to reliably prevent the surroundings from being contaminated by the overflowed silicon oil. .

In the second embodiment, the gap S is formed around the filter 309c. However, as shown in the third embodiment in FIG. 6, the gap S may be provided only on the downstream side of the filter 309c. Good.

Next, a description will be given, with reference to FIG. 7, of a filtering section 309 of a fourth embodiment of the releasing agent (silicone oil) supply device of the fixing device, which is a characteristic portion of the present invention.

The filtering section 309 has the same basic structure as that of the first embodiment, and includes a housing 309a, a filtering filter 309c, a supporting section 309b, and a collecting port 30.
9d, and the filtration filter 309c is
Areas of high range until the filtering capacity beyond the central portion from the upstream side, i.e., formed with fine eye filter 309c _1, region lower downstream of filtration capacity, i.e., the big eyes than the filter 309c ₁ It is formed by the filter 309c _2.

[0067] Thus, the long-term use or the like cause the upstream filter 309c ₁ clogging of the filtration filter 309c, even begins to store up silicone oil on the filtration filter 309c surfaces of the silicone oil to flow to the downstream side downstream filter 309c is collected in the oil tank 310 after passing through _two portions.

[0068] Since the filtration filter 309c filter 309c ₂ of the downstream side of the uses a large eye, although filtering capacity of impurities contained in the silicon oil is lowered as compared to the filter c ₁ on the upstream side, the eye due to impurities The clogging hardly occurs, the amount of silicon oil accumulated on the filtration filter 309c increases, and the silicon oil flows out of the filtration unit 309 from the upper opening of the housing 309a (the portion where the silicone oil is sent from the recovery pipe 308 into the housing 309a). The overflow can be prevented, and the surroundings can be reliably prevented from being contaminated by the overflowed silicone oil.

[0069]

According to the first aspect of the present invention, the release agent supplied onto the filter of the filtration section flows through the first flow path on the filter toward the other end, whereby the filtration is performed gradually. Therefore, the entire surface of the filter can be used for filtering the release agent, and the release agent can be efficiently filtered.

According to the second aspect of the present invention, since the release agent is positively caused to flow toward the other end by the inclination of the filter, the release agent stays on the clogged filter. In addition, the release agent can be efficiently filtered at the other end where clogging does not occur.

According to the third aspect of the present invention, the filtered release agent can be efficiently recovered from the filtered release agent recovery port on the downstream side of the second flow path to the storage section.

According to the fourth aspect of the present invention, since the first flow path and the second flow path of the filtration unit are provided along the width direction of the transfer material of the fixing device, the filtration area of the release agent is reduced. Can be increased without increasing the size, and the release agent can be filtered for a long period of time.

According to the fifth aspect of the present invention, since the filter portion is detachably formed, the filter containing the release agent can be easily replaced without contaminating the periphery with the release agent. Can be.

According to the sixth aspect of the present invention, since the clearance through which the release agent passes is provided between the filter and the filter at least on the downstream side of the first flow path, the entire filter is clogged. In addition, it is possible to reliably prevent the amount of the release agent remaining on the filter without being increased from overflowing to the outside of the filtration unit.

According to the seventh aspect of the present invention, since the filtering ability of the release agent is different between the upstream side and the downstream side of the filter in the filtering section, even if a part of the filter is clogged, the other part may be clogged. The release agent can be passed through the part, and while the release agent is filtered to the extent that no problem occurs, the amount of the release agent remaining on the filter without being filtered increases and overflows out of the filtration unit. Can be reliably prevented.

According to the eighth aspect of the present invention, the upstream side of the filter is in the first filtration region having a high filtering ability of the release agent, and the downstream side is in the first filtration region having a lower filtering ability of the release agent than the first filtering region. 2 Since it is formed in the filtration area, it is possible to perform high-precision filtration at the beginning of use, and if the upstream side of the filter is clogged due to long-term use, the amount of the release agent remaining on the filter without being filtered is reduced. It is possible to shorten the period in which the amount of the release agent for preventing the release agent from increasing and overflowing to the outside of the filtration unit is reduced to the extent that no problem occurs.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a digital color copying machine according to the present invention.

FIG. 2 is a perspective view showing Embodiment 1 of a release agent (silicone oil) supply device of the fixing device of the digital color copying machine of the present invention.

FIG. 3 is a sectional view of FIG. 2;

FIG. 4 is a cross-sectional view illustrating the filtration unit of FIG. 2;

5A and 5B show a filtration unit of a release agent (silicone oil) supply device of a fixing device of a digital color copying machine according to a second embodiment of the present invention, wherein FIG. 5A is a cross-sectional view, FIG. () Is a cross-sectional view as viewed from the side.

FIG. 6 is a cross-sectional view showing a filtration unit of a release agent (silicon oil) supply device of a fixing device of a digital color copying machine according to a third embodiment of the present invention.

7A and 7B show a filtration unit of a release agent (silicone oil) supply device of a fixing device of a digital color copying machine according to a fourth embodiment of the present invention, wherein FIG. 7A is a cross-sectional view, FIG. () Is a cross-sectional view as viewed from the side.

[Explanation of symbols]

 217 Fixing device 300, 301 Fixing roller 303 Coating roller 305 Blade 306 Felt 307 Oil receiving section 308 Recovery pipe 309 Filtration section 309a Housing 309b Support section 309c Filtration filter 309d Collection port 310 Oil tank 311 Pump

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshinobu Tateishi 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (72) Inventor Tsubasa Norihisa 22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka (72) Inventor Yasunori Mizuguchi 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Sharp Corporation (72) Inventor Toshiya Mikita 22-22 Nagaikecho, Abeno-ku, Osaka City, Osaka Sharp Co., Ltd. F-term (reference) 2H033 AA23 BA45 BA47 BB00

Claims (8)

[Claims] A release agent supply unit for supplying a toner release agent to a surface of a fixing roller of a fixing device for fixing the toner image transferred onto the transfer material by a pair of rotating rollers; A collection unit for collecting an excess of the release agent applied to the fixing roller by the application unit; a filtration unit having a filter for filtering impurities contained in the release agent collected by the collection unit; and a filtration unit. The release agent supply device of the fixing device, comprising: a storage unit that stores the filtered release agent; and a resupply unit that supplies the release agent stored in the storage unit again to the release agent supply unit. A collecting release agent supply unit for supplying the collected release agent onto one end of the filter of the filtering unit is provided. The filtering unit transmits the releasing agent supplied by the collected release agent supply unit onto the filter. Filter through the first flow path of the release agent flowing to the other end and the filter And a second flow path through which the released release agent flows. 2. The filter according to claim 1, wherein the filtering unit is configured to move from one end to the other end such that a flow of the release agent is generated in the housing from one end, which is upstream in the horizontal direction, to the other end, which is downstream in the housing. A filter disposed with an inclination, a first flow path using the upper space of the housing partitioned by the filter as a flow path, and a second flow path using the lower space of the housing partitioned by the filter as a flow path. The release agent supply device for a fixing device according to claim 1, wherein the release agent supply device comprises: 3. A filter release agent supply port for supplying a filtered release agent to the storage section at the other end of the filtration section downstream of the second flow path. Item 3. A release agent supply device for a fixing device according to Item 2. 4. The release agent supply device for a fixing device according to claim 1, wherein the first flow passage and the second flow passage of the filtration unit are provided along a width direction of the transfer material of the fixing device. . 5. The release agent supply device for a fixing device according to claim 1, wherein said filter portion is detachably formed. 6. A release agent supply device for a fixing device according to claim 2, wherein a gap through which the release agent passes is provided between at least the housing on the downstream side of the first flow path and the filter. . 7. A release agent supply unit for supplying a release agent for toner to a surface of a fixing roller of a fixing device for fixing a toner image transferred onto a transfer material by a pair of rotating rollers, and a release agent. A collection unit for collecting an excess of the release agent applied to the fixing roller by the application unit; a filtration unit having a filter for filtering impurities contained in the release agent collected by the collection unit; and a filtration unit. The release agent supply device of the fixing device, comprising: a storage unit that stores the filtered release agent; and a resupply unit that supplies the release agent stored in the storage unit again to the release agent supply unit. A collecting release agent supply unit for supplying the collected release agent onto one end of the filter of the filtering unit is provided. The filtering unit transmits the releasing agent supplied by the collected release agent supply unit onto the filter. Filter through the first flow path of the release agent flowing to the other end and the filter A second flow path through which the released release agent flows, and wherein the filtration ability of the release agent on the upstream side and the downstream side of the filter is made different from each other. apparatus. 8. The filter has an upstream side formed in a first filtration region having a high filtering ability of a release agent, and a downstream side formed in a second filtration region having a filtering ability of a release agent lower than the first filtration region. The release agent supply device for a fixing device according to claim 7, wherein