JPH08152801A - Fixing device - Google Patents

Abstract

PURPOSE: To provide a fixing device capable of effectively using a web by preventing an oil stain(oil dropping) on a paper(transfer paper) due to the web and also reducing the unneccesary oil exudation. CONSTITUTION: When the device is stopped after ending a job, or due to paper jamming, etc., a motor is actuated so as to rotate an eccentric circular cam 10, and to rotate a pressure lever 9 in a direction shown by arrow (a) while making a point (9a) as a fulcrum, then, a web roller 3 is completely separated from a fixing roller 1. Simultaneously, a link 13 is interlocked so as to rotate a feeding shaft 6 in a feeding direction through a one-way clutch 15, then, the sagging of the web 4 due to the separation of the web roller 3 is eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing device for fixing a developer on a transfer material, and more particularly to a fixing device for directly contacting a web with a fixing roller for cleaning and supplying oil.

[0002]

2. Description of the Related Art Conventionally, in this type of fixing device, as shown in FIG. 9, a web 4 is brought into contact with a fixing roller 1 via a web roller 3 to clean an unfixed developer adhering to the fixing roller 1. The method of supplying oil to the fixing roller 1 is adopted.

By rotation of the web 4, the motor M1 shown in FIG. 10, through the gears 12 and 11, the cam 8 and the lever 7, from the feed-out shaft 6 serving as a supply means, for example, 0.05 mm per sheet of transfer paper. Each time, the portion in contact with the fixing roller 1 is always wound on the winding shaft 5 as a winding means so that the portion is a new portion.

Then, as shown in FIG. 11, the transfer paper P sandwiched between the fixing roller 1 and the pressure roller 2 is
When the transfer sheet P is pulled out from the upstream side in the conveying direction in the case of paper jam or the like, the brake plate 21 is pressed against the delivery side in order to prevent the web 4 from loosening as shown by the broken line.

[0005]

However, the above-mentioned conventional example has the following problems.

1. Since the web 4 is constantly pressed against the fixing roller 1, when the machine is stopped for a while and then operated, there is a problem that the first few sheets of the transfer paper P are soiled by the oil that has gradually exuded.

2. Since the brake plate 21 is brought into contact with the delivery side, there is a problem that the oil of the web 4 oozes out at the brake plate 21 and the inside of the apparatus is contaminated, and in the worst case, the transfer sheet P is transported.

Therefore, the first invention according to the present application aims to prevent oil stains (oil dripping) on paper (transfer paper) by the web and to efficiently use the web by reducing wasteful oil bleeding. It is an object of the present invention to provide a fixing device that can be used.

Another object of the present invention is to provide a fixing device which can surely prevent oil bleeding.

Further, a third object of the present invention is to provide a fixing device capable of preventing the slack of the web without providing a brake plate and preventing oil bleeding at the contact portion of the brake plate. To do.

The fourth object of the present invention is to:
Prevents web slack without providing a brake plate, eliminates oil seepage at the contact part of the brake plate, and reliably prevents contact of the web with the fixing roller.
It is an object of the present invention to provide a fixing device capable of reducing oil seepage.

A fifth object of the present invention is to provide a fixing device which can achieve the object of the fourth invention with a simple structure.

The sixth object of the present invention is to:
It is an object of the present invention to provide a fixing device that can achieve the object of the first invention with a simple configuration.

Further, an object of a seventh invention according to the present application is to achieve the object of the first invention with a structure different from that of the sixth invention and having a simple structure. The object is to provide a fixing device that can perform.

The eighth object of the present invention is to:
It is possible to stop the feeding of the web without providing a brake plate and prevent slack, and to prevent the oil bleeding at the contact part of the brake plate and the oil bleeding due to the contact between the web and the fixing roller. The object is to provide a fixing device that can perform.

A further object of the ninth invention of the present application is to provide a fixing device which can achieve the above-mentioned object of the eighth invention with a simple structure.

A tenth invention of the present application is to provide a fixing device which can achieve the objects of the first invention and the fourth invention with a simple structure.

Further, an object of the eleventh invention according to the present application is a structure different from that of the ninth invention, and the objects of the first invention and the fourth invention by a simple structure. It is to provide a fixing device capable of achieving the above.

[0019]

According to a first aspect of the present invention, the above object is to provide a sheet pair containing a releasing agent, a roller pair of a fixing roller and a pressure roller for nipping and conveying a transfer material. Of the heat-resistant web, a supply means and a winding means for the web, and a pressing roller for bringing the web into contact with the fixing roller, and applying a release agent to the fixing roller while sequentially feeding the web. And a fixing device for fixing the developer image on the transfer material by the roller pair while performing cleaning, having a contact pressure releasing mechanism for the web, and using the contact releasing mechanism when the device is not operating. This is achieved by releasing the contact pressure of the web with respect to the fixing roller.

According to the second invention of the present application,
In the first aspect of the invention described above, the contact pressure releasing mechanism is achieved by separating the pressing roller from the fixing roller.

Further, according to a third invention of the present application, the above object is achieved when the contact pressure releasing mechanism releases the contact pressure of the web in the first or second invention. Is achieved by winding the loose web on the upstream side in the delivery direction or by winding it on the downstream side in the delivery direction.

According to the fourth invention of the present application,
The above-mentioned object is, in the above-mentioned first invention or second invention, when the contact pressure of the web is released by the contact pressure release mechanism, the slackened web is interlocked with the corresponding contact release mechanism and is fed in the feeding direction. This is achieved by providing slack removing means for winding on the downstream side.

Further, according to a fifth invention of the present application, in the above-mentioned fourth invention, the slack eliminating means for winding up on the downstream side in the feeding direction in cooperation with the contact pressure releasing mechanism is: This is achieved by having a link and a one-way clutch.

According to the sixth invention of the present application,
The above object can be achieved by the contact pressure release mechanism according to any one of the first to fifth inventions, wherein the contact pressure release mechanism includes a rotation drive means and an eccentric cam.

Further, according to a seventh invention of the present application, in the above object, in any one of the first invention to the fifth invention, the contact pressure releasing mechanism includes a solenoid and a link mechanism. It is achieved by

According to the eighth invention of the present application,
The above object can be achieved by any one of the first to seventh inventions, which has a driving unit of the web supply unit and a braking unit that applies a load by sliding.

Further, according to a ninth invention of the present application, in the above-mentioned eighth invention, the braking means comprises a pad made of resin or rubber and a pressing member for the pad. Achieved by

According to a tenth invention of the present application, in the above-mentioned sixth invention, the driving source of the slack eliminating means is a rotational driving means, and the driving source of the contact pressure releasing mechanism is the driving source. It is achieved by having the combined function.

Further, according to the eleventh invention of the present application, in the above-mentioned seventh invention, the driving source of the slack eliminating means is a solenoid, and also serves as the driving source of the contact pressure releasing mechanism. Be achieved by

[0030]

According to the first aspect of the present invention, the contact pressure releasing mechanism for the web releases the contact pressure of the web with respect to the fixing roller during the non-operation of the apparatus in which neither the cleaning operation nor the fixing operation is performed. Therefore, the release agent impregnated in the web does not exude.

According to the second invention of the present application,
In the first aspect of the present invention, since the pressing roller is separated from the fixing roller by the contact pressure releasing mechanism, the contact pressure of the web with respect to the fixing roller becomes substantially zero, and exudation of the release agent is eliminated.

Further, according to the third invention of the present application, in the first invention or the second invention, when the contact pressure of the web is released by the contact pressure release mechanism, the web is loosened. Since the web is wound upstream in the feed direction or wound downstream in the feed direction, contact of the loose web with the fixing roller is prevented without the use of a brake plate, which has conventionally occurred at the brake plate contact portion. Release agent does not seep out.

According to the fourth invention of the present application,
In the first invention or the second invention, when the contact pressure releasing mechanism releases the contact pressure of the web, the loose web is interlocked with the contact releasing mechanism and the downstream side in the delivery direction. Since the slack removing means for winding is provided, the slackened web is not brought into contact with the surface of the fixing roller by releasing the contact pressure, and the release agent does not seep out.

Further, according to the fifth invention of the present application, in the fourth invention, since the slack eliminating means includes the link and the one-way clutch, the contact pressure releasing operation can be performed with a simple structure. It works together to eliminate web slack.

According to the sixth invention of the present application,
In any one of the first to fifth inventions,
The contact pressure release mechanism includes a rotation drive means and an eccentric cam, and the rotation operation of the rotation drive means is converted into vertical movement by the eccentric cam to release the contact pressure of the web.

Further, according to a seventh invention of the present application, in any one of the first to fifth inventions, the contact pressure releasing mechanism includes a solenoid and a link mechanism, and the suction of the solenoid is performed. The action is transmitted by the link mechanism to release the contact pressure of the web.

According to the eighth invention of the present application,
In any of the above first to seventh inventions,
Since the braking means for rubbing against the driving part of the web supply means to apply a load is provided, there is no contact part between the braking means and the web as in the conventional case, and the release agent exudes at the contact part. Without sagging the web.

Further, according to a ninth invention of the present application, in the eighth invention, the braking means includes a pad made of resin or rubber and a pressing member for the pad, and the pressing member. Thus, the pad is rubbed against the drive unit of the supply unit to stop the operation of the supply unit.

According to the tenth invention of the present application, in the sixth invention, the driving source of the slack eliminating means is the rotation driving means, and also serves as the driving source of the contact pressure releasing mechanism. , The rotational movement of the rotary drive means is converted into vertical movement by the eccentric cam to release the contact pressure of the web,
The slack removing means is driven to remove the slack of the web.

Furthermore, according to the eleventh invention of the present application, in the seventh invention, the drive source of the slack eliminating means is a solenoid, and also serves as the drive source of the contact pressure releasing mechanism. The link mechanism transmits the suction operation of the above to release the contact pressure of the web, and also drives the slack removing means to remove the slack of the web.

[0041]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

(First Embodiment) FIG. 1 is a view best showing the features of the present invention. In FIG. 1, 1 is a fixing roller, 3 is a web roller as a pressing roller, 4 is a web, and 5 is a web.
Is a web winding shaft as a winding means, and 6 is a web feeding shaft as a supplying means.

During normal operation of the apparatus, when the rotation of the web drive motor M1 shown in FIG. 1 is transmitted to the cam 8 by the gear 12 and the gear 11, the spring 30 attaches to the eccentric shaft of the cam 8 by the spring 30 as shown in FIG. The biased lever 7 is swung in the direction of the arrow by the rotation of the cam 8 to rotate the winding shaft 5 supported by the one-way clutch 31 little by little.
The web 4 is wound up by 0.05 mm per sheet.

When the apparatus is stopped due to the end of the job or paper jam, the motor M2 as the rotation driving means shown in FIG. 3 is operated, and the eccentric cam 10 in the state shown in FIG. 4 is rotated by 180 ° as shown in FIG. Rotate. As a result, the pressure lever 9 constituting the contact pressure release mechanism rotates in the direction of the arrow a shown in FIG. 5 with 9a as the fulcrum, and the web roller 3 is completely separated from the fixing roller 1. Even if the web roller 3 is not completely separated from the fixing roller 1, the object of the present invention can be achieved by releasing the pressure.

At the same time when the pressure lever 9 rotates in the direction of the arrow a, the link 13 constituting the slack eliminating means interlocks,
As shown in FIG. 5, the web feeding shaft 6 is rotated in the feeding direction via the one-way clutch 15 which also constitutes the slack eliminating means, so that the slack of the web 4 caused by the separation of the web rollers 3 is eliminated.

After that, when the apparatus is operated again, the motor M2 is actuated, the eccentric cam 10 is rotated by 180 °, the pressure lever 9 is moved in the direction of the arrow b shown in FIG. 4, and the web roller 3 is set to the fixing roller 1. Pressurize.

A brake 14 as a braking means is provided on the web feeding shaft 6 to prevent the web 4 from loosening during the normal feeding operation.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. The first
The same parts as those of the above embodiment are designated by the same reference numerals and the description thereof will be omitted.

A second embodiment is shown in FIGS. 6 to 8. This embodiment is different from the first embodiment in that the operation of the pressure lever 9 is performed by the solenoid S and the link 18.

During operation of the apparatus, the solenoid S is turned on, and the web roller 3 is pressed against the fixing roller 1 as shown in FIG. Then, when the job is completed or the paper is jammed, the solenoid S is turned off, and the web roller 3 is separated from the fixing roller 1 as shown in FIG. The operation thereafter is the same as that of the first embodiment.

[0051]

As described above, the first aspect of the present application
According to the invention, since the contact pressure of the web with respect to the fixing roller is released by the contact pressure release mechanism of the web during the non-operation of the apparatus in which the cleaning operation and the fixing operation are not performed, the release agent impregnated in the web is released. It is possible to prevent the exudation of the agent, and it is possible to eliminate stains on the transfer paper and the fixing device due to the exudation of the release agent.

According to the second invention of the present application,
In the first aspect of the invention, since the pressing roller is separated from the fixing roller by the contact pressure releasing mechanism, the contact pressure of the web with respect to the fixing roller becomes almost zero, and the exudation of the release agent can be surely eliminated. Therefore, it is possible to surely eliminate the stains on the transfer paper and the fixing device due to the exudation of the release agent.

Further, according to the third invention of the present application, in the first invention or the second invention, when the contact pressure of the web is released by the contact pressure release mechanism, the web loosens. Since the web is wound upstream in the feed direction or wound downstream in the feed direction, contact of the loose web with the fixing roller is prevented without the use of a brake plate, which has conventionally occurred at the brake plate contact portion. The release agent can be prevented from seeping out, and the stress on the web other than the release agent supply section can be minimized while the machine is operating, so the release agent can be exuded at unnecessary places. It is possible to use the Web efficiently and eliminate waste of resources.

According to the fourth invention of the present application,
In the first invention or the second invention, when the contact pressure releasing mechanism releases the contact pressure of the web, the loose web is interlocked with the contact releasing mechanism and the downstream side in the delivery direction. Since the slack removing means for winding is provided, the slackened web is not brought into contact with the surface of the fixing roller by releasing the contact pressure, and the release agent can be more reliably prevented from oozing out.

Further, according to the fifth invention of the present application, in the above-mentioned fourth invention, since the slack eliminating means includes the link and the one-way clutch, the contact pressure releasing operation can be performed with a simple structure. The slack of the web can be removed in conjunction with each other.

According to the sixth invention of the present application,
In any one of the first to fifth inventions,
The contact pressure releasing mechanism includes the rotation driving means and the eccentric cam, and the contact pressure releasing mechanism for the web can be realized with a simple configuration.

Further, according to a seventh invention of the present application, in any one of the first to fifth inventions, the contact pressure releasing mechanism includes a solenoid and a link mechanism, and has a simple structure. Thus, the web contact pressure releasing mechanism can be realized.

According to the eighth invention of the present application,
In any of the above first to seventh inventions,
Since a braking means for rubbing against the drive part of the web supply means to apply a load is provided, the slack of the web is prevented while preventing the release agent from seeping out at the contact part between the conventional brake plate and the fixing roller. Can be prevented.

Further, according to the ninth invention of the present application, in the eighth invention, the braking means includes a pad made of resin or rubber and a pressing member for the pad, and has a simple structure. The operation of the supply means can be stopped.

According to the tenth invention of the present application, in the sixth invention, the driving source of the slack eliminating means is the rotation driving means and also serves as the driving source of the contact pressure releasing mechanism. , With a simple configuration, release the contact pressure of the web,
It is possible to remove the slack.

Further, according to the eleventh invention of the present application, in the seventh invention, the drive source of the slack eliminating means is a solenoid, and also serves as the drive source of the contact pressure releasing mechanism. With such a configuration, the contact pressure of the web can be released and the slack can be removed.

[Brief description of drawings]

FIG. 1 is a top view showing the overall configuration of a fixing device according to a first embodiment of the present invention.

FIG. 2 is a diagram for explaining a web driving method in the apparatus of FIG.

FIG. 3 is a top view of the fixing device according to the first exemplary embodiment of the present invention.

FIG. 4 is a front sectional view showing a state of the fixing device in operation according to the first embodiment of the invention.

FIG. 5 is a front sectional view showing a non-operating state of the fixing device according to the first embodiment of the invention.

FIG. 6 is a front sectional view showing a state of the fixing device in operation according to the second embodiment of the invention.

FIG. 7 is a front sectional view showing a non-operating state of the fixing device according to the second embodiment of the invention.

FIG. 8 is a top view of the fixing device according to the second exemplary embodiment of the present invention.

FIG. 9 is a front sectional view of a fixing device in a conventional example.

FIG. 10 is a top view of a fixing device in a conventional example.

FIG. 11 is a diagram showing a role of a brake plate in a conventional example.

[Explanation of symbols]

 1 Fixing Roller 2 Pressure Roller 3 Web Roller (Pressing Roller) 4 Web 5 Winding Shaft (Winding Means) 6 Feeding Shaft (Supplying Means) 9 Pressurizing Lever (Abutting Pressure Release Mechanism) 10 Eccentric Cam (Abutting Pressure) Release mechanism 13 Link (slack removing means) 14 Brake (braking means) 15 One-way clutch (slack removing means) 18 Link (contact pressure releasing mechanism) M2 Motor (rotation driving means) S Solenoid

Claims (11)

[Claims] 1. A roller pair of a fixing roller and a pressure roller that nip and convey a transfer material, a sheet-shaped heat-resistant web containing a release agent, a supply means and a winding means of the web,
A pressing roller for bringing the web into contact with the fixing roller, and while applying the cleaning agent to the fixing roller and sequentially cleaning the fixing roller, the developer on the transfer material is transferred by the roller pair. A fixing device for fixing an image has a contact pressure releasing mechanism for the web, and releases the contact pressure of the web with respect to the fixing roller by the contact pressure releasing mechanism when the device is not operating. Fixing device. 2. The fixing device according to claim 1, wherein the contact pressure releasing mechanism separates the pressing roller from the fixing roller. 3. When the contact pressure release mechanism releases the contact pressure of the web, the loose web is wound upstream in the delivery direction or is wound downstream in the delivery direction. The fixing device according to claim 1 or 2. 4. When the contact pressure releasing mechanism releases the contact pressure of the web, there is provided slack eliminating means for interlocking the loosened web with the contact pressure releasing mechanism to wind the slack web downstream in the feeding direction. The fixing device according to claim 1 or 2. 5. The fixing device according to claim 4, wherein the slack eliminating means that winds downstream of the contact pressure releasing mechanism in the delivery direction is provided with a link and a one-way clutch. 6. The fixing device according to claim 1, wherein the contact pressure releasing mechanism includes a rotation driving means and an eccentric cam. 7. The fixing device according to claim 1, wherein the contact pressure release mechanism includes a solenoid and a link mechanism. 8. The fixing device according to claim 1, further comprising a braking unit that applies a load by sliding on a driving unit of the web supply unit. 9. The braking means comprises a pad made of resin or rubber and a pressing member for the pad.
The fixing device described in 1. 10. The fixing device according to claim 6, wherein the drive source of the slack eliminating means is a rotation drive means, and also serves as a drive source of the contact pressure releasing mechanism. 11. The fixing device according to claim 7, wherein a drive source of the slack eliminating means is a solenoid, and also serves as a drive source of the contact pressure releasing mechanism.