JP2002296934A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device where maintenability is improved by having a heating device easily attached to and detached from an image forming device main body and where a good image can be obtained without the generation of image failure such as image blurring due to vibration of the heating device. SOLUTION: In the device, a pressing member 60 to energize a fixing device 118 toward a stay 50 which is fixed to a casing of the image forming device supporting the fixing device 118 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a heating device for heating a recording material carrying an image.

[0002]

2. Description of the Related Art For example, an image forming apparatus such as a copying machine, an LBP, a facsimile, a micro film reader printer, an image display (display) device, and a recording device includes an image heating device for heating a recording material carrying an image, A heating device such as a heat fixing device is provided.

For example, such a heating device uses a recording material (transfer material) using a developer (toner) made of a heat-meltable resin or the like by an appropriate image forming process such as electrophotography, electrostatic recording, or magnetic recording. Sheet, electrofax sheet, electrostatic recording sheet, printing paper, etc.)
2. Description of the Related Art There has been known a fixing device that heat-fixes an unfixed toner image corresponding to target image information formed and supported by a method or a direct method on a recording material surface as a permanently fixed image.

Such a heating device is not only a fixing device as described above, but also a surface improving device for heating a recording material carrying an image to improve the surface properties (such as glossiness). It can be widely used as a means for heating a body to be heated, such as a dressing device.

The fixing device includes, for example, a fixedly supported heating element, a fixing film that is a heat-resistant film conveyed while being pressed against the heating element, and a heating target material via the fixing film. The recording material has a pressing member for bringing the recording material into close contact with the heating member, and the heat of the heating member is applied to the recording material via a fixing film, so that the unfixed image formed and supported on the recording material surface is recorded on the recording material. A heating device of a film heating type for heating and fixing a surface has been devised.

[0006] Such a film heating type heating device can use a heating element or a thin film having a low heat capacity and a rapid rise in temperature, so that it is possible to save power and shorten the wait time (quick start property). This has the advantage that the temperature inside the apparatus such as an image forming apparatus can be reduced, and is effective.

The heating device is detachably attached to the image forming apparatus main body in order to facilitate service maintenance.

FIG. 4 is a diagram showing an example of a state in which such a heating device is attached to an image forming apparatus main body.

For example, as shown in FIG. 4, such a heating device is provided in a hole provided in a stay 50 as a support attached to a housing of the image forming apparatus, at a position (upstream side) of the frame 11 in the paper transport direction. The insertion portion 11b provided at the forward position in the mounting direction of the heating device is inserted, and the downstream position of the frame 11 in the paper transport direction (the forward position in the detaching direction of the heating device).
The frame 11 is fixed to the stay 50 with screws.
Therefore, the heating device shown in FIG. 4 can be attached to and detached from the main body of the image forming apparatus entirely in the direction of arrow B.

Further, gears 30 to 33, which are gear trains for driving the heating device, are provided in the main body of the image forming apparatus. The gear 33 is provided on the heating device side, is mounted coaxially with the pressing member of the heating device, and can rotate simultaneously. The gear 30 is connected to a motor (not shown), and the heating device is driven by the motor.

[0011]

FIG. 5 is an enlarged view of a portion where the insertion portion 11b of the frame 11 is inserted into the stay 50. As shown in FIG.

In the heating device mounted on the main body of the image forming apparatus as shown in FIG. 4, the insertion portion 11b and the hole are formed in a fitting relationship as shown in FIG. In mass production, play occurs. When the width f of the insertion portion 11b is 10 mm, the difference g−f = 2h from the width of the hole is 13 μm to 85 μm.
m.

The heating device receives a force from the gear 32 in the direction of arrow R. The direction of R is the direction of the pressure angle θ of the gear 32. Then, although the heating device is fastened to the stay 50 by the screw, the heating device tends to be moved counterclockwise in the figure around the bent portion 11c of the frame 11. Specifically, an attempt is made to move in the direction of the rotation component arrow S of the arrow R.

Then, as described above, since the insertion portion 11b and the hole have play, the heating device moves within that range. Actually, the gear vibrates by repeatedly moving counterclockwise each time the gear teeth mesh and returning clockwise between the meshes.

Then, the recording material is moved to the nip portion N of the heating device.
, The recording material vibrates according to the vibration of the heating device. Then, the recording material also vibrates in the transfer section (not shown) on the upstream side of the paper conveyance, and the image is blurred. In addition, when the vibration is large, a strange sound may be generated.

Therefore, according to the present invention, the heating device can be easily attached to and detached from the main body of the image forming apparatus, so that maintenance can be improved, and image defects such as image blur due to vibration of the heating device can be prevented. It is an object of the present invention to provide an image forming apparatus capable of obtaining a good image.

[0017]

According to the present application, an object of the present invention is to provide an image forming apparatus that records an image formed by a series of image forming processes on a recording material, and includes a device for forming an image. An image forming apparatus comprising: a housing to be heated; a heating device for heating a recording material carrying an image; and a support fixed to the housing or a member attached to the housing and supporting the heating device. This is achieved by the first invention in which a biasing member that biases the heating device toward the support is provided.

Further, according to the present application, the above object is achieved in the first aspect, wherein the heating device is detachable from the support, and the heating device and the support are mounted in the mounting direction of the heating device. And a fixing portion capable of fixing the heating device to the support at a front position in a detaching direction of the heating device, wherein the heating device is fixed to the fitting portion. A drive input portion located between the drive input portion and the drive input portion, and the biasing member biases the heating device at a position closer to the fitting portion than the drive input portion. This is also achieved by the second invention.

Further, according to the present application, the above object is also achieved by the third invention in which the urging member is an elastic body in the first invention or the second invention.

According to the present application, the above object is achieved by any one of the first to third inventions, wherein the heating device comprises:
The present invention is also achieved by a fourth invention in which the fixing device fixes the unfixed image to the recording material and permanently fixes the unfixed image by performing a heat treatment on the recording material carrying the unfixed image.

Further, according to the present application, the above object is achieved by any one of the first to third inventions, wherein the heating device performs a heating process on a recording material carrying an unfixed image to thereby determine the undetermined state. The present invention is also achieved by the fifth invention, which is a hypothetical fixing device that temporarily fixes a fixed image on the recording material.

Further, according to the present application, the above object is achieved by any one of the first to third inventions, wherein the heating device comprises:
The present invention is also achieved by a sixth invention which is a surface improving apparatus for improving the surface properties of the recording material by subjecting the recording material carrying the fixed image to heat treatment.

[0023]

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

First, an overall configuration of the image forming apparatus according to the present embodiment will be described with reference to FIG.

As shown in FIG. 1, such an image forming apparatus has a scanner section B as image reading means for reading image information of a book document at an upper portion of an image forming apparatus main body A, and an image forming section C at a lower portion thereof. , And a seat deck D is further assembled thereunder.

The scanner section B includes a scanning system light source 201,
It is configured to include a platen glass 202, a document pressure plate 203 that can be opened and closed with respect to the apparatus main body A, a mirror 204, a lens 205, a light receiving element (photoelectric conversion element) 206, an image processing unit (not shown), and the like. . Then, a book original such as a book, thick paper, or curled paper, a sheet original, or the like is placed on the platen glass 202 with the original surface facing down.
When the reading start key is depressed by pressing the back surface by pressing the back surface of the platen glass 03, the scanning system light source 201 scans the lower part of the platen glass 202 in the direction of arrow a in FIG. read. Image information of a document read by the scanning light source 201 is processed by the image processing unit, converted into an electric signal, and transmitted to the laser scanner 111.

Here, the image forming apparatus main body A functions as a copying machine when a processing signal of the image processing unit is input to the laser scanner 111, and functions as a printer when an output signal of the computer is input. If a signal from another facsimile apparatus is received or a signal from the image processing unit is transmitted to another facsimile apparatus, the apparatus functions as a facsimile apparatus.

On the other hand, a sheet cassette 1 is mounted below the image forming section C, and the sheet cassette 1 is composed of a lower cassette 1a and an upper cassette 1b as one feeding unit. In the present embodiment, two feeding units U1 and U2 are mounted, and four cassettes are mounted. One upper feeding unit U1 is detachably attached to the apparatus main body A, and the lower feeding unit U2 is detachably attached to the sheet deck D.

The sheet as a recording material accommodated in the cassettes 1a and 1b is fed out by a pickup roller 3 serving as a feeding rotating body as described later, and is fed by a cooperative action of a feed roller 4 and a retard roller 5. After being separated and fed one by one, the sheet is conveyed by conveyance rollers 104 and 105, guided by a registration roller 106, and fed to the image forming unit C by the registration roller 106 in synchronization with the image forming operation.

In addition to the sheet cassette 1, a manual feed tray 110 is disposed on the side of the apparatus main body A.
The sheet S on the manual feed tray 110 is the manual feed roller 1
In step 09, the sheet is fed to the registration roller 106.

The image forming section C includes a photosensitive drum 112 which is an electrophotographic photosensitive drum, an image writing optical system 113,
The image forming apparatus includes a developing device 114 and a transfer charger 115. Then, a laser beam corresponding to image information emitted from the laser scanner 111 is scanned on the surface of the photosensitive drum 112 uniformly charged by the charger by the image writing optical system 113 to form a latent image. A toner image is formed on the image by a developing device 114, and a transfer charger 115 applies the first image of the sheet to a sheet conveyed in synchronization with the rotation of the photosensitive drum 112 by a registration roller 106.
The toner image is transferred to the surface.

The sheet on which the toner image is formed is conveyed by a conveying unit 117 to a fixing device 118 as a heating device, where the sheet is heated and pressed to fix the toner image on the sheet surface. Is discharged and loaded on the sorter 120 arranged in the first place.

When an image is recorded on both sides of the sheet, the sheet discharged from the fixing device 118 is sandwiched by discharge rollers 119, and when the rear end of the sheet passes the branch point 207, the discharge rollers are rotated in reverse. And sheet double-sided tray 12
After the sheet is once placed on the sheet 1, the sheet is conveyed by the conveying rollers 104 and 105 and reaches the registration roller 106. The image of the inverted sheet is formed on the second surface in the same manner as described above. It is configured to be discharged and loaded into

Next, the fixing device 118 which is a heating device according to the present invention will be described.

FIG. 2 is a longitudinal sectional view of the fixing device 118 cut along the sheet conveying direction.

FIG. 3 is a sectional view showing a schematic configuration of the fixing device 118.

As shown in FIG. 3, the fixing device 118 includes a frame 11 of the fixing device 118 and a fulcrum 11 on the frame 11.
The upper frame 12 is rotatably supported about a, the thin plate-shaped heater 13 as a heat source for fixing toner, and a pressure roller (pressure member) rotatably held by the frame 11. 14. The frame 11 holding the heater 13
A film guide 15 held movably in a pressing direction, a fixing film 16 for guiding a recording medium, a heater stay 17 for uniformly pressing the film guide 15, and a heater 13 And a pressure pin 19 attached to the upper frame 12 while being movable in the direction in which the pressure spring 18 extends.

As described above, in the fixing device 118,
The heater 13 and the pressing roller 14 held by the film guide 15 are pressed against each other by the pressing spring 18 with the fixing film 16 interposed therebetween, forming a pressing nip (fixing nip) N. 14 is driven at a predetermined speed in the counterclockwise direction in the drawing, the fixing film 16 rotates following the rotation of the fixing film 16 and the toner image T is carried in a state where the temperature of the heater 13 is controlled to a predetermined fixing temperature. The toner image T is fixed on the sheet S by introducing the sheet S into the nip portion N and performing a heating process while nipping and conveying.

The fixing device 118 is detachably attached to the image forming apparatus main body in order to facilitate service maintenance.

As shown in FIG. 2, the fixing device 118 includes a stay 5 serving as a support attached to the housing of the image forming apparatus.
The insertion portion 11b provided at a position on the upstream side of the frame 11 in the paper conveyance direction (a position ahead of the fixing device 118 in the mounting direction) is inserted into the hole provided at 0, and the downstream side of the frame 11 in the paper conveyance direction. The frame 11 is fixed to the stay 50 with screws at a position (a position in the detaching direction of the fixing device 118). Therefore, the fixing device 118 can be attached to and detached from the image forming apparatus main body all in the direction of arrow B.

In the fixing device 118, gears 30 to 33, which are gear trains for driving the fixing device 118, are provided in the main body of the image forming apparatus. The gear 33 is connected to the fixing device 11.
8 and is mounted coaxially with the pressing member, and can rotate simultaneously. The gear 30 is connected to a motor (not shown), and the fixing device 118 is driven by the motor.

Although the insertion portion 11b and the hole are formed in a fitting relationship as described in the above-mentioned conventional example, play occurs in mass production. That is, as shown in FIG. 5, when the width f of the insertion portion 11b is 10 mm, the difference g−f = 2h from the width of the hole is about 13 μm to 85 μm.

On the other hand, on the image forming apparatus side, a stay 70 provided as a housing in the image forming apparatus main body and a pressing member 60 as an urging member are attached. Holding member 60
Is formed of an elastic body, one end of which is fixed to the stay 70, and the other end of which biases the fixing device 118 downward. Therefore, the pressing member 60 tries to press the fixing device 118 in the direction of arrow P. But,
Since the fixing device 118 is fixed to the stay 50 by a screw, the fixing device 118 is pressed around the frame bending portion 11c in the direction of arrow Q, which is the rotation direction component of arrow P. In the present embodiment, the pressing force of the pressing member 60 is set so that (moment by arrow Q)> (moment by arrow S). That is, assuming that the distances from the frame bending portion 11c to the respective action points in the urging by the pressing member 60 are m and n, the setting is made so as to satisfy nQ> mSQ = PcosαS = Rcosβ.

As a result, the fixing device 118 is
The force is further applied in the direction of arrow R, and the bent portion 11 of the frame 11 is
Even if an attempt is made to move in the counterclockwise direction in the drawing (the direction of the rotation component arrow S in the direction of arrow R) around the center c, the pressing force by the pressing member 60 is suppressed by the rotation direction component Q and rather fixed downward. Is done. Therefore, the recording material is fixed to the fixing device 1
18, even when the recording material reaches the nip portion N of the fixing device 11
A good image can be obtained without vibrating in accordance with the vibration of No. 8. Further, since the fixing device 118 itself does not vibrate, there is of course no sound generation.

In this embodiment, the fixing device 118 is urged toward the stay 50 by an elastic member from above the fixing device 118, but the urging direction by the elastic member is not limited to this. It is. For example, an elastic member may be provided below the fixing device 118 so that the fixing device 118 is lifted up. In this case, the urging pressure set by the elastic member may be set so that the weight of the fixing device 118 can be sufficiently increased.

In the present embodiment, the fixing device is described as an example of the heating device. However, the present invention is not limited to the fixing device as described above. The present invention can also be widely applied to a surface improving device for reforming, a hypothetical deposition device for hypothetical deposition, and the like, as well as a means for heating the object to be heated.

[0047]

As described above, according to the first aspect of the present invention, since the urging member urges the heating device toward the support, the heating device can be imaged. It can be easily attached to and detached from the main body of the forming apparatus, so that maintenance can be improved, and good images can be obtained without causing image defects such as image blur due to vibration of the heating device.

According to the second invention of the present application,
The heating device and the support are fitted to each other at a forward position in a mounting direction of the heating device, and the heating device is fixed to the support at a forward position in a detaching direction of the heating device. The drive of the heating device is input between the position and the fixed portion, and the biasing member biases the heating device toward the support at a position closer to the fitting portion than the drive input portion. Therefore, the heating device can be easily attached to and detached from the main body of the image forming apparatus, and the maintenance performance can be improved.
A good image can be obtained without causing image defects such as image blur due to vibration of the heating device.

Further, according to the third aspect of the present invention, since the elastic body urges the heating device toward the support, the heating device can be easily moved with respect to the image forming apparatus main body. In addition to improving the maintainability, it is possible to obtain a good image without causing image defects such as image blur due to vibration of the heating device.

According to the fourth aspect of the present invention,
Since the urging member urges the fixing device toward the support, the fixing device can be easily attached to and detached from the image forming apparatus main body. A good image can be obtained without causing image defects such as image blur due to vibration of the apparatus.

Further, according to the fifth aspect of the present invention, since the urging member urges the hypothetical attachment device toward the support, the hypothetical attachment device is attached to the image forming apparatus main body. On the other hand, it can be easily attached and detached, the maintenance performance can be improved, and a good image can be obtained without causing image defects such as image blur due to vibration of the temporary attachment device.

According to the sixth invention of the present application,
Since the urging member urges the surface improving device toward the support, the surface improving device can be easily attached to and detached from the image forming apparatus main body, and the maintenance performance can be improved. A good image can be obtained without causing image defects such as image blur due to vibration of the surface improving device.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a state in which the heating device provided in FIG. 1 is attached to an image forming apparatus main body.

FIG. 3 is a sectional view illustrating a schematic configuration of a heating device provided in FIG. 1;

FIG. 4 is a diagram illustrating a state in which a conventional heating device is attached to an image forming apparatus main body.

FIG. 5 is an enlarged view of a fitting portion between the heating device of FIG. 4 and a housing attached to the image forming apparatus main body.

[Explanation of symbols]

 11b Insertion part (fitting part) 50 Stay (support) 60 Holding member (biasing member, elastic body) 118 Fixing device (heating device)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H033 AA01 AA36 BA25 BA59 BB18 BB30 BB34 BB37 BE03 2H071 BA03 BA13 BA16 CA01 CA05 DA12 DA26

Claims (6)

[Claims] 1. An image forming apparatus for recording an image formed by a series of image forming processes on a recording material, comprising: a housing containing a device for forming an image; Urging member for urging the heating device toward the support in an image forming apparatus including a heating device to be heated and a support fixed to the housing or a member attached to the housing and supporting the heating device. An image forming apparatus comprising: 2. The heating device is detachable from the support. The heating device and the support are fitted to each other at a position in the mounting direction of the heating device. A fixing portion that can fix the heating device to the support at a forward position of the detachment direction, wherein the heating device is located between the fitting portion and the fixing portion, and the driving of the heating device is input. The image forming apparatus according to claim 1, further comprising an input unit, wherein the urging member urges the heating device at a position closer to the fitting unit than the drive input unit. 3. The image forming apparatus according to claim 1, wherein the urging member is an elastic body. 4. The fixing device according to claim 1, wherein the heating device is a fixing device for fixing the unfixed image to the recording material and permanently fixing the unfixed image by performing a heating process on the recording material carrying the unfixed image. Item 4. The heating device according to any one of items 3. 5. The heating device according to claim 1, wherein the heating device is a hypothetical fixing device for temporarily fixing the unfixed image to the recording material by performing a heating process on the recording material carrying the unfixed image. 4. The heating device according to claim 3. 6. The heating device according to claim 1, wherein the heating device is a surface improving device that improves a surface property of the recording material by performing a heating process on the recording material carrying the fixed image. The heating device according to claim 1.