JP2000242103A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device low in cost, superior in maintenability and also superior in productivity. SOLUTION: In the image forming device provided with a transfer mechanism where a toner image is transferred to a transfer material and a paper feeding mechanism that carries the before mentioned transfer material to a transfer position, a transfer material carrying part 20 that is formed in an endless belt state and installed spread on plural rolls and impressed with voltage, a driving roll 19 that revolves the transfer material carrying part 20, a facing plate 17 installed on an opposite side of the before mentioned transfer material carrying part 20 through a bundle of transfer material 7c and grounded and a separating mechanism 186 that prevents more than 2 pieces of the transfer material 7a from being carried to the transfer position, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer system for transferring a toner image onto a transfer material in a direction perpendicular to or parallel to a transfer direction of the transfer material, and to an image forming apparatus having a paper feed mechanism.

[0002]

2. Description of the Related Art In recent years, toner-type image forming apparatuses capable of forming clear images with excellent resolution, such as laser printers, have become widespread.

For example, Japanese Patent Application Laid-Open No. 9-230715 discloses that
A fixing means for fixing the toner image transferred from the toner image carrier carrying the toner image to the transfer material, wherein the toner image carrier is separated from the transfer material when the transfer material is transported. An image forming apparatus that transfers a toner image to a transfer material by moving the toner image carrier in a direction perpendicular to the transfer material conveyance direction when the transfer material is stopped '' has been disclosed. Very suitable for promoting cost reduction.

Hereinafter, the conventional orthogonal transfer type image forming apparatus will be described with reference to the drawings.

FIG. 4 is a schematic configuration diagram of a conventional image forming apparatus, FIG. 5 is a perspective view showing a transfer process of the conventional image forming apparatus, and FIG. 6 is a toner image carrier of the conventional image forming apparatus. And FIG. 7 is a schematic view showing a paper feed mechanism of a conventional image forming apparatus.

4 to 7, reference numeral 1 denotes a toner image carrier formed of an endless belt and formed of a photoreceptor belt, the surface of which is coated with a layer of an organic photoconductive material. Reference numeral 2 denotes charging means disposed around the toner image carrier 1 for uniformly charging the surface of the toner image carrier 1 to about -600 V; 3 developing means for converting an electrostatic latent image into a visible image;
3a is a negatively charged toner, 3b is a developing roller for pressing the toner 3a against the surface of the toner image carrier, and 3c is a toner when the toner 3a pressed against the surface of the toner image carrier 1 is transferred to an electrostatic latent image. The formed toner image, 3d is the toner transferred to the transfer material, and 4 is the toner that recovers the toner 3a remaining on the surface of the toner image carrier 1 as waste toner, and physically cleans the surface of the toner image carrier 1. Cleaning means, 5
A neutralizing means for neutralizing negative charges remaining on the surface of the toner image carrier 1 and electrically cleaning the surface of the toner image carrier 1; 6 irradiating a laser beam based on the image signal sent Then, the surface potential of the exposed portion of the toner image carrier 1 is raised to −100 V to form an electrostatic image on the surface of the toner image carrier 1, exposure means 7, transfer material 8, toner image 3 c on transfer material 7 9 is a cassette containing the transfer material 7, 10 is a transfer roller supported when the transfer material 7 is transferred to the transfer position, 11 is a feed roller pressed against the uppermost transfer material 7 b, Reference numeral 12 denotes a transfer material holding unit driving roller driven by a motor or the like, 13 denotes a transfer material holding unit which is formed in an endless belt shape and is rotated by the transfer material holding unit driving roller 12, and 14 denotes a transfer opposing roller 8.
Is a support roller for rotating the toner image carrier 1 around the circumference, and 16 is a transfer material carrier portion rotatably disposed at an inner circumferential position of the transfer material carrier 13. The rollers 18a are friction pads for separating the uppermost transfer material 7b and the transfer material bundle 7c.

The operation of the conventional image forming apparatus configured as described above will be described below with reference to the drawings.

When the toner image carrier 1 rotates around, the surface of the toner image carrier 1 that has passed through the charging means 2 is charged. Next, the surface of the toner image carrier 1 is irradiated with laser light by the exposing means 6 to form an electrostatic latent image. Here, the exposure means 6 may use not only a laser but also an LED or an LCD. Next, the toner image 3c is transferred onto the transfer material 7.
Transcribe At the time of transfer to the transfer material 7, as shown in FIG. 6, the transfer of the transfer material 7 electrostatically attracted to the transfer material holding unit 13 is temporarily stopped, and the transfer material 7 is stopped at the transfer position. At the same time, the rotation of the toner image carrier 1 is stopped. Then, the portion of the toner image carrier 1 where the toner image 3c is formed is rubbed against the transfer material 7 by rolling the transfer opposing roller 8 from the back side, and the toner image carrier 1 is moved from the left end F to the right end G for one step. Displace. As a result, the negatively charged toner image 3 c is attracted from the surface of the toner image carrier 1, separated and transferred to the transfer material 7. The transfer opposing roller 8 moved to the right end G is displaced again by one step in the direction from the right end G to the left end F. The transfer end surface of the toner image carrier 1 after the transfer is sequentially separated from the transfer material 7 as the transfer opposing roller 8 passes. At this time, the toner image carrier 1 is displaced on the transfer material 7 in a direction orthogonal to the transport direction of the transfer material 7. Each time the transfer for one process is completed, the transfer opposing roller 8
Is moved out of the area of the transfer material 7 after passing over the transfer material 7, so that the toner image carrier 1 is separated from the transfer material 7. Then, the transfer of the transfer material 7 is started, but the transfer distance of the transfer material 7 is only the effective transfer width of the toner image carrier 1.

Next, a paper feed mechanism of a conventional image forming apparatus will be described with reference to the drawings.

As shown in FIG. 7, the transfer material bundle 7c is set on a cassette 9 or a tray, and the uppermost transfer material 7b in contact with the feed roller 11 is pulled out by the frictional force of the feed roller 11 and separated. It reaches the nip of the friction pad 18a, which is a mechanism. When the uppermost transfer material 7b keeps moving forward, the lower transfer material is also pulled out due to friction between the transfer materials. However, when the lower transfer material enters the nip portion, friction occurs with the lower transfer material. Since the frictional force with the pad 18a is larger than the frictional force between the transfer materials, the lower transfer material 7 is prevented from advancing, and only the uppermost upper transfer material 7b is transported.

After repeating the above steps, the transfer material 7 is intermittently sent to the fixing means (not shown) by the effective transfer width to perform non-contact fixing.

[0012]

However, the above-mentioned conventional image forming apparatus requires a feed roller, a transport roller to a transfer material carrying section, a motor for driving the drive roller, a drive system component such as a gear, and the like. There were problems that the system became complicated, the cost increased, and the maintainability and productivity were poor.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide an image forming apparatus which is low in cost, excellent in maintainability, and excellent in productivity.

[0014]

In order to solve the above-mentioned problems, an image forming apparatus according to the present invention comprises a toner image carrier formed in an endless belt shape and stretched by a plurality of rollers; A supporting roller for rotating the
A transfer opposing roller disposed at an inner peripheral position of a closed loop of the toner image carrier so as to be able to perform a reciprocating stroke operation in a forming direction of the toner image carrier, a displacement roller displaced following the transfer opposing roller, An image forming apparatus comprising: a transfer mechanism that transfers a toner image carried on the toner image carrier to a transfer material by continuous pressing of a transfer facing roller; and a paper feed mechanism that transports the transfer material to a transfer position. Wherein the paper feeding mechanism is formed in an endless belt shape, is stretched by a plurality of rollers, and a voltage is applied to the transfer material carrier, a driving roller for rotating the transfer material carrier circumferentially, and the transferer One or more transfer materials in contact with the lowermost surface of the material carrier, an opposing plate disposed to press the lowermost surface of the one or more transfer materials and grounded, and the one or more transfer materials Is two or more transfer It has a separate mechanism for preventing the conveyed to location, the configuration with.

According to this configuration, it is possible to provide an image forming apparatus which is low in cost, excellent in maintainability, and excellent in productivity.

[0016]

In order to achieve this object, an image forming apparatus according to a first aspect of the present invention comprises a toner image carrier formed in an endless belt shape and stretched by a plurality of rollers; A support roller for rotating the toner image carrier circumferentially; a transfer opposing roller disposed at an inner peripheral position of a closed loop of the toner image carrier so as to be able to perform a reciprocating stroke in a forming direction of the toner image carrier; A displacement roller that is displaced following an opposing roller, a transfer mechanism that transfers a toner image carried on the toner image carrier to a transfer material by continuous pressing of the transfer opposing roller, and a transfer mechanism that transfers the transfer material to a transfer position. A paper feed mechanism for transporting, a transfer material carrying unit, wherein the paper feed mechanism is formed in an endless belt shape, stretched by a plurality of rollers, and a voltage is applied thereto; A drive roller for rotating the transfer material carrying portion around, one or more transfer materials in contact with the lowermost surface of the transfer material carrying portion, and a lower surface of the one or more transfer materials are arranged to be pressed. And a separation mechanism for preventing the one or more transfer materials from being conveyed to the transfer position. Since the transfer material that is in contact with the transfer material can be transported to the transfer position by rotating the transfer material carrying portion around, it is possible to reduce the number of drive system components such as a feed roller, the transfer material carrying portion and its driving motor, and gears. This has the effect of reducing costs, improving maintainability, and improving productivity.

Here, the transfer system may be an orthogonal transfer system or a parallel transfer system.

The transfer material carrying portion preferably has at least a two-layer structure composed of a dielectric and a conductor, and has a conductor on the inner periphery and a dielectric on the outer periphery. Thus, when a voltage is applied to the drive roller, the voltage is also applied to the transfer material carrying unit.

The drive roller has a structure in which a conductive rubber is provided around a metal core in order to obtain a necessary frictional resistance between the drive roller and the transfer material supporting portion. What has the structure mentioned above is used.

As the separating mechanism, a mechanism which is grounded and made of a conductive material and has a function of holding down the transfer material other than the uppermost transfer material when the transfer material is conveyed to the transfer position is used.

According to a second aspect of the present invention, there is provided the image forming apparatus according to the first aspect, wherein the opposing plate and / or the separating mechanism is provided on a cassette or tray on which a transfer material bundle is set. Claim 1
In addition to the operation described above, since the opposing plate and / or the separation mechanism are integrated with the cassette or the tray, the cost can be further reduced, and the maintenance is excellent, and the operation is excellent in productivity.

Here, as the cassette or tray, the transfer material bundle can be attached to and detached from the paper feeding section, paper can be easily supplied and exchanged, and the capacity of paper is about 100 to 500 sheets. The one having a built-in spring at the bottom and having a structure for pressing the transfer material to the transfer material holding portion is preferably used.

According to a third aspect of the present invention, there is provided the image forming apparatus according to the first aspect, wherein the paper feeding mechanism is formed in an endless belt shape, and a transfer material holding unit to which a voltage is applied. A drive roller for rotating the transfer material carrier around, a roll-shaped transfer material in which the transfer material is wound in a roll, and a cutter unit for cutting the roll-shaped transfer material to a predetermined length. Even when a roll-shaped transfer material is used, the transfer material in contact with the transfer material holding portion can be conveyed to the transfer position by rotating the transfer material holding portion around, so that a feed roller or a transfer material can be used. It is possible to reduce the number of the driving system components such as the supporting portion, its driving motor, and gears, so that the cost can be reduced, and the effect that the maintenance is excellent and the productivity is excellent can be obtained.

Here, in order to further strongly electrostatically attract the transfer material to the transfer material holding portion, it is preferable to provide an opposing roller for pressing the transfer material against the transfer material holding portion.

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of a transfer process of the image forming apparatus of the orthogonal transfer system according to the first embodiment of the present invention as viewed from a transfer material transport direction. FIG. FIG. 3 is a schematic diagram viewed from the direction shown in FIG.

1 to 3, reference numeral 1 denotes a toner image carrier, 2 denotes charging means, 3 denotes developing means, 3a denotes toner, 3b
, A developing roller; 3c, a toner image; 3d, toner transferred to a transfer material; 4, cleaning means;
Is an exposure means, 7a is a transfer material conveyed to a transfer position, 7a
Reference numeral b denotes an uppermost transfer material, 7c denotes a transfer material bundle, 8 denotes a transfer opposing roller, 9 denotes a cassette, 14 denotes a displacement roller, 15 denotes a support roller, and 16 denotes a transfer material carrying portion driven roller. Therefore, the same reference numerals are given and the description is omitted.

Reference numeral 17 denotes an opposing plate which is grounded and disposed on the inner bottom surface of the cassette 9 via a spring (not shown). Reference numeral 19 denotes a transfer material holding unit driving roller for rotating the transfer material holding unit around.
Reference numeral 19a denotes a core of the transfer material carrier driving roller 19, which is a metal roller core to which a voltage is applied, and 19b denotes a roller core 19a.
A conductive rubber 20 is provided around the outer periphery of the transfer member 7 and is made of a dielectric and a conductor that carries the transfer material 7b and conveys it to the transfer position.
A transfer material carrier having a layer structure, 20a is a conductor forming a layer on the inner peripheral side of the transfer material carrier 20, 20b is a dielectric forming a layer on the outer peripheral side of the transfer material carrier 20, 18b Reference numeral denotes a grounded separation claw, which is a separation mechanism disposed on the inner wall of the cassette 9 and for preventing two or more transfer materials from being conveyed to the transfer position.

The operation of the image forming apparatus of the present embodiment configured as described above will be described below with reference to the drawings.

When a voltage is applied to the metal roller core 19a, a voltage is also applied to the conductor 20a via the conductive rubber 19b. Also, the opposite plate 17 grounded on the opposite side (the inner wall of the cassette) via the transfer material carrying portion 20, the uppermost transfer material 7b, and the transfer material bundle 7c is provided. 20 is electrostatically attracted. At this time, since the spring is provided between the opposing plate 17 and the inner bottom of the cassette 9, the uppermost transfer material 7b is
And more strongly electrostatically attracted. The transfer material carrier drive roller 19 is driven by a drive motor (not shown), and the transfer material carrier 20 is rotated to convey the uppermost transfer material 7b attracted to the transfer material carrier 20 to the transfer position. At this time, since the separation claw 18b is disposed so that the distance between the separation claw 18b and the transfer material carrying portion 20 is substantially equal to the thickness of the uppermost transfer material, the transfer material one sheet below the uppermost transfer material 7b is conveyed. Never.

Next, the toner image 3c on the toner image carrier 1
Is transferred to the transfer material 7a conveyed to the transfer position, a voltage having a polarity opposite to that of the toner 3d is applied to the transfer material holding unit 20, and the transfer opposing roller 8 is moved. Transfer facing roller 8
Goes through the position of A and moves to B. Then, the sheet returns to pass through the position A and returns to the position of the transfer opposing roller 8. At this time, the toner image 3c is transferred to the transfer material 7a at the transfer position of the stationary transfer material holding unit 20. After this transfer, the transfer material 7 is shifted in the transfer material feed direction when performing the next transfer. At this time, the transfer material carrier driving roller 19
Is driven by a drive motor, so that the transfer material holding unit 2
0 and the transfer material 7 electrostatically attracted thereto are shifted, and the image forming operation is continued.

In this embodiment, the case of the orthogonal transfer system is described, but the same effect can be obtained also in the case of the parallel transfer system.

The image forming operation according to the present embodiment is the same as that of the prior art, and the description is omitted.

[0033]

As described above, according to the image forming apparatus of the present invention, the following excellent effects can be obtained.

According to the first aspect of the present invention,
The transfer material that is in contact with the transfer material carrier can be conveyed to the transfer position by rotating the transfer material carrier around, thus reducing the number of drive system components such as the feed roller, transfer material carrier, its driving motor, and gears. This makes it possible to provide an image forming apparatus which can be manufactured at a low cost, is excellent in maintainability, and is excellent in productivity.

According to the second aspect of the present invention,
In addition to the effect of the first aspect, since the opposing plate and / or the separation mechanism are integrated with the cassette or the tray, the cost can be further reduced, and the image forming apparatus having excellent maintainability and excellent productivity can be provided. It is possible to do.

According to the third aspect of the present invention,
Even when a roll-shaped transfer material is used, the transfer material in contact with the transfer material holding portion can be conveyed to the transfer position by rotating the transfer material holding portion around, so that the feed roller and the transfer material holding portion and the driving thereof It is possible to reduce the number of driving system components such as motors and gears, to reduce costs, to provide an image forming apparatus that is excellent in maintenance and high in productivity.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a transfer process of an image forming apparatus of an orthogonal transfer system according to a first embodiment of the present invention when viewed from a transfer material transport direction.

FIG. 2 is a schematic view of FIG. 1 viewed from a direction rotated by 90 ° with respect to a transfer material transport direction.

FIG. 3 is an enlarged view of a main part of FIG. 2;

FIG. 4 is a schematic configuration diagram of a conventional image forming apparatus.

FIG. 5 is a perspective view showing a transfer process of a conventional image forming apparatus.

FIG. 6 is a schematic diagram showing a state of displacement of a toner image carrier of a conventional image forming apparatus.

FIG. 7 is a schematic diagram illustrating a sheet feeding mechanism of a conventional image forming apparatus.

[Explanation of symbols]

 Reference Signs List 1 toner image carrier 2 charging means 3 developing means 3a toner 3b developing roller 3c toner image 3d toner transferred to transfer material 4 cleaning means 5 static elimination means 6 exposure means 7 transfer material 7a transfer material 7b top transfer material 7c transfer material bundle REFERENCE SIGNS LIST 8 Transfer opposing roller 9 Cassette 10 Conveying roller 11 Feed roller 12 Transfer material holding unit drive roller 13 Transfer material holding unit 14 Displacement roller 15 Support roller 16 Transfer material holding unit driven roller 17 Opposite plate 18a Friction pad 18b Separation claw 19 Transfer material holding Unit drive roller 19a Roller core 19b Conductive rubber 20 Transfer material carrier 20a Conductor 20b Dielectric

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kokichi Kawaji 1006 Kadoma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. Terms (reference) 2H032 AA05 BA01 BA12 BA18 BA23

Claims (3)

[Claims] 1. A toner image carrier formed in an endless belt shape and stretched by a plurality of rollers; a supporting roller for rotating the toner image carrier around; and an inner peripheral position of a closed loop of the toner image carrier. A transfer opposing roller disposed so as to be capable of reciprocating stroke operation in a direction in which the toner image carrier is formed, a displacement roller that is displaced following the transfer opposing roller, and the toner that is continuously pressed by the transfer opposing roller. An image forming apparatus comprising: a transfer mechanism that transfers a toner image carried on an image carrier onto a transfer material; and a paper feed mechanism that conveys the transfer material to a transfer position, wherein the paper feed mechanism is an endless A transfer material supporting portion formed in a belt shape and stretched by a plurality of rollers to which a voltage is applied; a driving roller for rotating the transfer material supporting portion; and a lowermost surface of the transfer material supporting portion One or more transfer materials, an opposing plate disposed to press the lowermost surface of the one or more transfer materials and grounded, and transporting two or more of the one or more transfer materials to the transfer position An image forming apparatus comprising: a separation mechanism for preventing the image forming operation from being performed. 2. The image forming apparatus according to claim 1, wherein the opposing plate and / or the separation mechanism are disposed on a cassette or a tray on which a transfer material bundle is set. 3. The transfer mechanism according to claim 1, wherein the paper feed mechanism is formed in an endless belt shape, and a transfer material carrier to which a voltage is applied, a driving roller for rotating the transfer material carrier around, and a transfer material wound in a roll shape. The image forming apparatus according to claim 1, further comprising a roll-shaped transfer material, and a cutter unit that cuts the roll-shaped transfer material into a predetermined length.