JPH03238473A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent a roller or a guide part on the carrying path of a transfer paper from being contaminated by the unfixed toner of the transfer paper by providing a cooling device which cools the transfer paper on the downstream side from the fixing device setting position in the carrying direction of the transfer paper. CONSTITUTION:The transfer paper where a transfer toner image is fixed by fixing devices 11 and 19 is cooled by the cooling device 111 provided on the downstream side in the carrying direction of the transfer paper. As a result, the temperature of the transfer paper is lowered and the fixing performance thereof is accelerated. Besides, the transferred toner image is quickly made in a perfect fixed state. As the result, the unfixed toner does not exist on the transfer paper which is carried on the carrying path L. Thus, the rollers 1 - 3 or the guide parts 24 and 25 on the carrying path L are prevented from being contaminated as a result of unfixed toner being attached to the rollers 1 - 3 or the guide parts 24 and 25.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an image forming apparatus, and more particularly to an electrostatic photographic image forming apparatus.

[Traditional technique? 11f] Conventionally, an electrostatic latent image of the original is formed on a photoreceptor by exposing the original, this electrostatic latent image is developed to form a toner image of the original on the photoreceptor, and this toner image is transferred to a transfer paper. An electrostatic photographic image forming apparatus is known that transfers and fixes an image onto a document and forms an image of a document on the transfer.

According to this conventional image forming apparatus, the image of the document fed to the document feed section of the main body of the device is transferred to the transfer paper fed to the transfer paper feed section, and the transferred toner image is fixed by the fixing device. The transfer paper on which the original image is formed is conveyed through a conveyance path within the apparatus main body and taken out from the apparatus main body. Note that a vertical copying apparatus is disclosed in Japanese Patent Laid-Open No. 12363/1983.

[Problems to be Solved by the Invention] In the conventional image forming apparatus described above, the transfer toner image is fixed by the fixing device, and the heated transfer paper passes through the conveyance path.

Therefore, the transfer paper passes through the conveyance path without the transferred toner image being completely fixed on the transfer paper.
Unfixed toner may adhere to rollers and guide portions provided in the conveyance path, and these rollers and guide portions may become contaminated with unfixed toner.

The present invention has been made in view of the current state of this type of image forming apparatus described above, and its purpose is to prevent the rollers and guide portions of the transfer paper conveyance path from being contaminated by unfixed toner on the transfer paper. The purpose of the present invention is to provide an image forming apparatus that is

[Means for Solving the Problems] In order to achieve the above object, a case is provided with a plurality of process units that operate in each process of image formation, and by operating each of these process units, the image is transported within the case. In an image forming apparatus that transfers and fixes an image of a document onto a transfer paper, the invention according to claim (1)
A cooling device for cooling the transfer paper is provided downstream of the fixing device setting position in the transfer direction of the transfer paper.

The invention according to claim (2) provides the image forming apparatus with a cleaning roller for removing unfixed toner adhering to the transfer paper downstream of the fixing device setting position in the transfer direction of the transfer paper. The structure is as follows.

In the image forming apparatus, a cleaning plate for removing unfixed toner is brought into contact with a roller in a conveyance path through which the transfer paper passes.

[Function] In the invention described in claim (1), the transfer paper on which the transferred toner image is fixed by the fixing device is cooled by the cooling device provided on the downstream side in the conveyance direction of the transfer paper. Therefore, the temperature of the transfer paper is lowered and the fixing properties are accelerated, and the transferred toner image quickly becomes completely fixed, so that there is no unfixed toner on the transfer paper conveyed through the conveyance path.

Therefore, unfixed toner does not adhere to the rollers and guide portions of the conveyance path and these rollers and guide portions are not contaminated with toner.

In the invention described in claim (2), unfixed toner on the transfer paper is removed by a cleaning roller provided on the downstream side of the fixing device in the conveyance direction of the transfer paper, and the rollers and guide portions of the conveyance path are free from toner. It cannot be contaminated.

Further, in the invention described in claim (3), unfixed toner adhering to the rollers of the conveyance path through which the transfer paper passes is removed by a cleaning blade that comes into contact with these rollers,
The rollers and guide portions of the conveyance path are not contaminated with toner.

[Example code] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

1 to 3 are perspective views showing the external structure of the embodiment, FIG. 1 is a perspective view when not in use, and FIGS. 2 and 3 are perspective views in the preparation process for copying, respectively. It is.

As shown in these figures, in the embodiment, the case C of the main body is composed of a front cover 101, a rear cover 104, side covers ↓02, 103, a bottom cover 107, and a manual document feed table 61.

This manual document feed table 61 is provided with a handle 106, and can be opened and closed relative to the case C by rotating the handle 106 around the side edge on the side cover 102 side. There is.

2 and 3 show a case where the manual document feed table 61 is opened, and the upper surface 108 of the case C includes an operation section 51,
Toner exchange lid 63. Open/close switch 36 and louver 10
5 is provided. Further, a pair of side guides 2 are attached to the open surface of the manual document feed table 61, and the distance between the sight guides 2 can be adjusted.

In this way, the interval between the side guides 62 of the opened manual document feed table 6↓ is adjusted according to the document width size, and the document is inserted into the case C from between the sight guides 2 of the manual document feed table 61. It is now possible.

The cassette storage section IA stored in the case C can be pulled out from the front cover 101 as shown in FIG. Then, the cassette 5 with the transfer paper set in the cassette storage part 1A follows the cassette guide 115 of the cassette storage part IA pulled out from the front cover lo1.
2 can be inserted and set.

Further, when the manual document feed table 61 is opened as described above, the open/close switch 36 is activated and warm-up is started, and the fixing heater, fluorescent lamp heater, and cooling fan, which will be described later, complete warm-up after about 20 seconds. The display is performed only on a display section (not shown). Furthermore, when the cassette storage section IA with the cassette 52 inserted and set is pushed into the case C, the set state is detected and a set display is displayed on a display section (not shown).

FIG. 4 is an explanatory diagram showing the internal configuration of the embodiment, FIG. 5 is an explanatory diagram showing the configuration of the paper feed section of the embodiment, FIG. 6 is an explanatory diagram showing the configuration of the drive section of the embodiment, and FIG. 8 is an enlarged explanatory view of the fixing device portion of the embodiment, and FIG. 8 is a circuit diagram of the electrical unit of the embodiment.

As shown in FIG. 4, transport guides 24, 25. The relay roller 2° 3.4 and the document supply roller 1 form a document conveyance path. The upper opening of this document transport path is set near the set positions of the opened manual document feed table 61 and the site guide 62, and the document placed on the manual document feed table 61 passes through the upper opening. The document can be transported through the document transport path.

In the vicinity of the opening, a document feed sensor 31 is disposed along the conveyance path, and the relay roller 2 and the document feed roller 1
In between, a document holding section 26 and a contact glass 7 are provided on the conveyance path and facing the document holding section 26.

On the back side of the contact glass 7, a heater 18 of a 5° fluorescent lamp, and a rinser 6 are arranged, and constitute a document reading section that optically scans the document. Further, a leading edge detection sensor 32 is arranged between the contact glass 7 and the relay roller 2 along the document conveyance path. Furthermore, an optical sensor unit 35 for reading the image density and size of the original is provided near the setting position of the rinse 6, so that the image density and size of the original can be detected.

Between the relay rollers 3 and 4, the document conveyance path branches to form a transfer paper conveyance path L3, and this transfer paper conveyance path L5 is guided by guide plates 46 and 47 to carry the transfer paper inserted and set in the case C. It is also guided to a separate case C3 which is used by being connected to the case C as appropriate.

As shown in FIG. 5, the transfer paper P is set in the cassette 52, the cassette 52 is covered with a cassette lid 52C, and the anti-buckling spring 52S attached to the cassette lid 52C causes the transfer paper P to be is prevented from shifting internally.

A feed roller 21 is disposed near the tip of the cassette 52, and a pickup roller 21P is attached to a cam that is rotatable around the feed roller 21. Further, a paper presence/absence sensor 37 is attached to the cassette 52.

When the cassette 52 is inserted into the case C, the pickup roller 2IP is positioned above and away from the transfer paper P, and when the leading edge detection sensor 32 detects the leading edge of the document, the feed roller 21 and the pickup roller 21
P is driven, the pickup roller 21P moves in a direction in which it contacts the transfer paper P, feeds the transfer paper P to the position of the foot roller 21, and rotates away from the transfer paper P again.

In transfer paper transport ML, a registration roller 13 is provided downstream of the feed roller 21 in the transport direction of the transfer paper P, a transfer charger 12 is provided downstream of this registration roller 13, and a transfer charger 12 is provided near the registration roller 3. A registration sensor 33 is arranged at.

Near the branching point between the document transport path and the transfer paper transport path Ls,
The configuration is as shown in FIG.
A fixing device 1t109 consisting of a fixing device 9 and a pressure roller 11 is provided, and a cleaning roller 110 is further provided downstream of the fixing device 109.

Above the fixing device 109 and the cleaning roller 110, a suction cooling fan 10a and a blowing cooling fan 10 are provided.
A cooling device 111 is provided for cooling the transfer paper P and the like. Further, a cleaning blade 3b for removing toner adhering to the relay roller 3 is in contact with the relay roller 3 disposed near the ventilation cooling fan 10b.

As shown in FIG. 7, the cooling bag M111, the cleaning roller 110, and the fixing device 109 are housed in a sealed case 112 to prevent the toner from diffusing to the outside.

As shown in FIG. 4, a photoreceptor 41 wound around rollers 41a and 41b is disposed approximately in the center of the case C.
At the wrapping position with respect to the roller 41b, the photoreceptor 41 is closely opposed to the transfer charger 12.

Further, at the winding position with respect to the roller 41a, the photoreceptor 41
faces the rinser 6, and at this position, the rinser 6 forms an image of reflected light from the original on the photoreceptor 41. A cleaning device 9 is disposed in contact with the photoreceptor 41 between the rinse 6 and the transfer charger 12,
Between the cleaning device 9 and the rinse 6, a static eliminating LED array 8 is placed on the side of the cleaning device 9, and a main charger 16 is placed on the side of the rinse 6, each of which is placed close to and opposite to the photoreceptor 41.

A developing device 5 is disposed downstream of the rinse 6 in the direction in which the photoconductor 41 is transported, and is disposed close to and facing the photoconductor 41, and between the developing device 15 and the transfer charger 12.
A seam sensor 34 is arranged close to and opposite the photoreceptor 41 .

Next, the drive devices for the document conveyance system, transfer paper conveyance system, and photoreceptor drive system will be explained.

As shown in FIG. 6, the drive device of the embodiment has a solenoid 116 for a motor gear IIA driven by a motor.
By driving, either the forward gear 117 or the reverse gear 118 is switched into engagement. The figure shows a state in which the forward rotation gear 117 is engaged with the motor gear IIA, the output gear 119 is engaged with the forward rotation gear 117, and
This output gear 119 is connected to a document drive gear 120. Relay gear 1
22 and a main body active gear 121 having a one-way clutch 123 are engaged.

The document transport gear 120 is connected to each roller 1, 2, 3.4 for transporting the document via a power transmission mechanism (not shown), and the main body drive gear 121 is connected to the rollers 1, 2, 3.4 for transferring the document via a power transmission mechanism (not shown). It is connected to the rollers 11, 13, 21 for paper conveyance, the roller 41b for driving the photoreceptor, and the like. Note that the one-way clutch 123 is connected to the main body drive gear 121.
Only when the motor gear IIA rotates clockwise, the driving force of the motor gear IIA is transmitted to a shaft (not shown).

In the state shown in FIG. 6, when motor gear IIA rotates clockwise, rotation is transmitted to each gear as shown by thin arrows, output gear 119 rotates clockwise, and document drive gear 120 rotates counterclockwise. As a result, the rollers 1, 2.degree. 3.4 are driven in the document conveyance direction via a power transmission mechanism 41 (not shown). At this time, the one-way clutch 123 idles, and rotation is not transmitted to the shaft provided with the main body drive gear 123, so that the transfer paper conveyance roller and the photoreceptor 41 are not driven.

When the solenoid 116 is driven from the state shown in the figure, the motor gear IIA engages with the reversing gear 118, rotation is transmitted to each gear as shown by the thick arrow, and the document drive gear 20 rotates clockwise. Therefore, the document transport rollers l, 2,
The rotation direction of 3.4 is reversed, and the original can be conveyed in the ejection direction.

In this case, the main body drive gear 123 also rotates clockwise.

The transfer paper conveying rollers 11, 13, 21, photoreceptor 41, etc. can be driven in a predetermined rotation direction.

In this manner, in the state shown in FIG. 6, only the document drive system is driven by the document drive gear 120 by the motor driven by the detection signal of the document feed sensor 31. Furthermore, when the solenoid 116 is driven, the document opening gear 120 drives the document drive system, and the main body drive gear 123 drives the transfer paper feeding system and the photoreceptor drive system at the same time. .

The circuit of the electrical unit of the embodiment is as shown in FIG.
The AC line includes an interlock switch 300° 301, a noise filter 302, a main switch 303, a triac 304, a sir T-stat 305, a halogen heater 306, a main motor 307, and a fan motor 308,3.
It consists of 07.

In addition, a DC line constituted by a DC power supply 311 via a power transformer 310 is connected to a power back transformer 312.
It is connected to the transfer charger 12 via. 22V
The line is connected to the total counter 3 via the relay board 314.
15, paper feed solenoid 316, registration solenoid 31
7 is connected.

The relay board 314 is connected to the main PCB 318 so as to be able to send and receive signals, and the 22V line of the main PCB 318 includes a fluorescent lamp 5, a fluorescent lamp ballast 320, a power back converter 321, a static elimination LED array 8, and a fluorescent lamp heater. 18 are connected. The output of the power back converter 321 is supplied to the main charger 16 via the varistor 87a.

The 5V line from the DC power supply 311 is connected to the paper feed sensor 325 through the relay board 314. It is connected to a paper discharge sensor 326 and a thermistor 327. Similarly, the 22V line is connected to the dimming sensor 32 via the main PCB 318.
8. Collected toner sensor 329° seam sensor 330, pulse generator 331° toner end detection sensor 332
It is connected to the.

Next, the operation of the embodiment having the above-described configuration will be explained.

When the manual document feed table 61 is opened, the opening/closing switch 36 is turned on and warm-up is started, and after about 20 seconds, the warm-up of the fixing heater 17 of the fixing roller 19, the heater 18 of the fluorescent lamp 5, and the cooling device 111 is completed. Then, a message indicating that the warm-up has been completed is displayed on the display section.

It has been pulled out from the front cover 101. Cassette storage part I
When the cassette 52 containing the desired size of transfer paper P is inserted along the cassette guide 115 of A, and the cassette storage section 1A is inserted into the case C, the insertion sensor detects the cassette sensor and the paper presence/absence sensor 37. A message indicating that the setting is complete will be displayed on the display section.

The side guide 62 of the manual document feed table 61 is adjusted to the document width, and the yK document is inserted through the manual document feed table 61 from the opening of the document conveyance path.

When the inserted document hits the document feed roller 1 and the document feed sensor 31 detects the document, skew correction time is secured and the document feed roller 1 is removed after a certain period of time has passed.
starts driving. At the same time, the fluorescent lamp 5 is turned on.

In this state, the drive device is in the driving state shown in FIG. 6, the main body active gear 121 is not driven, and the document is conveyed downward along the document conveyance path. When the trailing edge of the document is detected by the leading edge detection sensor 32, the motor is stopped and conveyance of the document is stopped. The image density and size of the image are read.

After a certain period of time, the solenoid 116 shown in FIG. 6 is activated, the motor resumes driving, and the document is switched back in the opposite direction, upward.

The document conveyed upward is pressed against the contact glass 7 by the document holding unit 26, and the reflected light from the document surface of the light projected onto the document from the fluorescent lamp 5 is transferred to the rinse 6.
The image is projected onto the photoreceptor 41 by the following steps.

In this state, the photoreceptor 41 is driven by restarting the drive of the motor, and in synchronization with this, the transfer charger 2 and the static eliminator LE are activated.
The D array 8, main charger 16, and cleaning device 9 are turned on. Therefore, after the residual toner is cleaned by the cleaning device 9 and the static electricity removal process is performed by the static elimination LED array 8, the main chassis charger 16
Projection by the rinse 6 is performed on the surface of the photoreceptor 41 that is uniformly charged at the photoreceptor 41 . An electrostatic latent image of the document is formed on the image.

The original that has been exposed in this way is transferred to the original supply roller 1. The document is ejected from the document transport path to the outside of the case C by the relay rollers 2, 3.4.

The photoreceptor 41 on which the latent image of the document is formed is transferred to the developing device 15 position, and the latent image is visualized into a toner image by the developing device E15.

On the other hand, when the motor resumes driving, a paper feed solenoid (not shown) is turned on, and the clutch of the paper feed unit is driven, and the paper stacked in the cassette 52 is moved by the feed roller 21 and pickup roller 21P, which are engaged with the clutch. One sheet is taken out and sent to the feed roller 21,
They are separated and conveyed by the friction pad 22.

The separated transfer paper passes through a transfer paper transport path consisting of guide plates 46 and 47 and comes into contact with the registration rollers 13, and the registration rollers 13 are driven by a clutch engaged with the shaft of the registration rollers 13. Then, the transfer paper is conveyed so as to come into contact with the developed image on the photoreceptor 41 at the transfer charger 12 position.

In this case, the registration sensor 33 detects the jam.

The registration roller 13 can also be driven by a detection signal from a seam sensor of the photoreceptor 41.

The toner image on the photoreceptor 41 is transferred by the transfer charger 12 onto the transfer paper transported in this manner.

The transfer paper on which the toner image has been transferred is held under pressure between a fixing roller 19 and a pressure roller 11 in a fixing device 109 shown in FIG. Unfixed toner is removed.

In the embodiment, by the cold air from the cooling device 1i111,
Since the guide plates, cleaning roller 110, and transfer paper in the transfer paper transport path L3 and original transport path are cooled, the toner on the transfer paper after fixing is rapidly cooled, the toner quickly becomes completely fixed, and the unfixed toner is removed. It becomes almost non-existent.

Even if there is a small amount of unfixed toner left on the transfer paper, this toner is removed by the cleaning roller 110.

Even if a small amount of unfixed toner remains on the transfer paper conveyed on the document conveyance path and this toner adheres to the relay roller 3, this toner is removed by the cleaning blade 3b. No toner remains.

When the registration sensor 33 confirms that no jam has occurred and the document feed sensor 31 detects the passage of the trailing edge of the transfer paper, a signal is given to the seam sensor 34, and the seam sensor 34 detects the passage of the photoreceptor belt 41. The motor is turned off at the position where the detection mark is detected. At the same time, the transfer charger 12, the static elimination LED array 8, and the fluorescent lamp 5 are turned off.

The main charger 16 is turned off when the document is conveyed upward in the document conveyance path and the end of the document passes through the rinse 6 position. Further, the paper feed solenoid is turned off in synchronization with the ON of the register solenoid, and the registration solenoid is turned off in synchronization with the detection of the trailing edge of the transfer paper by the document feed sensor 31.

The transfer paper on which one image has been formed in this way is transferred to case C.
The copy processing operation is completed and the state is reached.

When the manual document feed table 61 is closed after all copy processing is completed, the open/close switch 36 is turned OFF.
Heater 18 for fluorescent lamp 5, fixing heater 1 for fixing roller 19
7. The suction cooling fan 10a and the ventilation cooling fan 10b of the cooling device 111 are turned off.

As described above, according to the embodiment, the cooling device 111 controls the transfer paper transport path Ls, the document transport path, and the cleaning roller 1.
10 and the transfer paper are cooled, the toner on the transfer paper quickly becomes completely fixed, and the remaining unfixed toner is removed by the leaning roller 110.

Even if residual unfixed toner adheres to the relay roller 3 for some reason, this toner will be removed by the cleaning blade 3b, so that it will not damage the document transport path, the relay rollers 2 and 3, and even the document feed roller 1. , not contaminated with toner.

Therefore, toner does not stain the original or the transfer paper.

In the above embodiment, part of the document transport path and the transfer paper transport path Ls are shared, but as shown in FIG.
It is also possible to completely separate both transport paths and L5. In this way, it becomes possible to take out the original and the transfer paper separately, making it convenient to use.

Furthermore, in the above embodiments, a so-called vertical type image forming apparatus in which the photoreceptor 41, document conveyance path, etc. are formed in a vertical direction has been explained as an example, but a so-called horizontal type image forming apparatus in which the photoreceptor 41, etc. are formed in a horizontal direction has been described. It can also be applied to other image forming apparatuses.

[Effects of the Invention] As explained in detail above, according to the invention set forth in claim (1), the transfer paper, the conveyance path through which the transfer paper is conveyed, and the rollers disposed on the conveyance path are cooled by a cooling device. Therefore, the transfer paper is quickly fixed, and the amount of unfixed toner adhering to the conveyance path and rollers can be significantly reduced.

According to the invention set forth in claim (2), even if unfixed toner exists on the transfer paper, this unfixed toner is removed by the cleaning roller disposed immediately after the fixing device, and the conveyance path and rollers are removed. No more smearing with toner.

Further, according to the invention described in claim (3), even if unfixed toner from the transfer paper passing through the conveyance path adheres to the rollers in the conveyance path, this toner is removed by the cleaning blade, and the rollers become contaminated with toner. There's nothing to do.

[Brief explanation of drawings]

FIGS. 1 to 8 are diagrams explaining one embodiment of the present invention,
Fig. 1 is a perspective view showing the external structure when not in use, Figs. 2 and 3 are perspective views showing the external structure in the preparation process for copying, Fig. 4 is an explanatory view showing the internal structure, and Fig. 5 is a perspective view showing the external structure when not in use. Figure 6 is an explanatory diagram showing the configuration of the paper feed section, Figure 6 is an explanatory diagram showing the configuration of the active part, Figure 7 is an enlarged explanatory diagram of the fixing device section, Figure 8 is a circuit diagram of the electrical unit, and Figure 9 FIG. 3 is a sectional view showing another embodiment of the present invention. 1...Document supply roller, IA...Cassette storage section, 2-4...Relay roller, 5...
・Fluorescent lamp, 6... Rinse, 7... Platen glass, 8... Static elimination LED array, 9...
・Cleaning device, 11... Pressure roller, 12.
...Transfer charger, 13...Registration roller,
15...Developing device, 16...Main charger, 18...Heater, 19...Fixing roller, 21...Feed roller, 21P...
... Pickup roller, 22 ... Friction butt, 24.25 ... Conveyance guide, 26.
...Document holding unit, 31...Document feed sensor, 32...Tip detection sensor, 33...Registration sensor, 34...Seam sensor, 41 ...
... Photoreceptor, 46.47 ... Guide plate, 51.
...Operation unit, 52...Cassette, 61.
...Manual document feed table, 62...Side guide, 63...Toner exchange lid, 101...
...Front cover 102.103...Side cover, 104...Rear cover, 105...
・Louva, 107...Bottom cover 108...
...Top surface, 109...Fixing device, 110...
Cleaning roller, 111... Cooling device. 115...Cassette guide, 307...
・Main motor, 310...Power transformer, 3
11...DC power supply, 312...Power back transformer, 314...Relay board, 318...
...Main PCB, L...Conveyance path, L,
...branch conveyance path. 1 Figure 1 Figure 4 Figure 183 Figure 5 Figure 1 Figure 16 Figure 7 Diagram Figure 9

Claims (3)

[Claims] (1) A case is equipped with a plurality of process units that operate in each process of image formation, and by operating these process units, the image of the original is transferred and fixed onto the transfer paper conveyed within the case. An image forming apparatus characterized in that a cooling device for cooling the transfer paper is provided downstream of a fixing device setting position in the conveyance direction of the transfer paper. (2) A case is provided with a plurality of process units that operate in each process of image formation, and by operating each of these process units, the image of the original is transferred and fixed onto the transfer paper conveyed within the case. An image forming apparatus characterized in that a cleaning roller for removing unfixed toner adhering to the transfer paper is provided downstream of a fixing device setting position in the conveyance direction of the transfer paper. (3) Image formation in which a case is equipped with a plurality of process units that operate in each process of image formation, and by operating these process units, an image of a document is transferred to transfer paper that is conveyed within the case. An image forming apparatus characterized in that a cleaning blade for removing unfixed toner is brought into contact with a roller in a conveyance path through which the transfer paper passes.