JP2000337464A - Endless belt and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endless belt capable of preventing the inclined running and the meandering of the endless belt hung on a plurality of rollers to be circulated, and an image forming device using the endless belt, and capable of reducing the failure and the running cost. SOLUTION: An endless belt comprises an endless base 51a having a pair of projections 51b expanded by a predetermined length over both sides from axial both ends of a roller 52, a pair of ribs 53 made of the tape-shaped elastic members extended in the belt running direction, formed on the surfaces 51c at the roller 52 side, of the pair of projections 51b, and respectively contacting with both ends 52a of the roller 52 for controlling the axial relative position of the roller with respect to the roller 52, and a pair of resin tapes 54 formed on the surfaces 51d opposite to the surfaces 51c provided with the ribs 53, of both ends in the width direction of the endless belt 51, having a width W2 at least two times as large as a width W1 of the rib 53, and including a reinforcement material woven inside thereof.

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 used for an electrophotographic copying machine, a printer, and the like.

[0002]

2. Description of the Related Art As an image forming apparatus used in an electrophotographic copying machine or a printer, for example, an intermediate transfer type color image forming apparatus using an intermediate transfer belt is widely used. The color image forming apparatus includes a photosensitive drum on which a toner image is formed on the surface by an electrophotographic process, and an intermediate transfer belt disposed so as to contact the photosensitive drum at a predetermined transfer position. The primary transfer of a plurality of color toner images sequentially formed on the intermediate transfer belt is performed so as to be superimposed once on the same location on the intermediate transfer belt to form a multiple toner image. The multi-toner image transferred on the sheet is fixed by a fixing device to be a color image.

In addition, a so-called tandem type color image forming apparatus using a paper transfer belt is also known. In this type of color image forming apparatus, a plurality of image forming units that form toner images of different colors are arranged side by side on a paper transport transfer belt that adsorbs and carries a paper and transports the paper, and the toner formed by each image forming unit is arranged. The image is transferred so as to be superimposed on the same place on the paper carried on the paper transport transfer belt to form a multi-toner image on the paper, and finally fixed to form a color image.

In an endless belt that is stretched by a plurality of rolls and circulates in a predetermined traveling direction, such as an intermediate transfer belt or a paper transport transfer belt used in these image forming apparatuses, the endless belt is stretched and supported. Due to variations in the parallelism of the rotating shafts of the rolls and the outer diameter of the rolls, and unevenness in the tension due to the change in the circumference of the endless belt itself, the endless belt does not travel straight and moves in the axial direction of the roll. Traveling in a displaced state, that is, a so-called one-sided running or meandering may occur. When such offset running or meandering occurs, the transfer positions of the toner images sequentially transferred to the endless belt or the toner images sequentially transferred to the paper carried on the endless belt are shifted, and finally, Image defects such as color shift and hue change may occur in a color image formed on paper.

In order to prevent the endless belt from running or meandering, for example, Japanese Patent Application Laid-Open No. 58-100145 discloses a method in which a flange is provided on a drive roll. Japanese Unexamined Patent Publication No. Hei 5-333707 discloses a method in which a rubber guide member is provided at an end portion in the width direction of a belt, and JP-A-59-230950 and JP-A-62-50873 disclose a method in which a belt is provided in the width direction. For bonding a hot-melt adhesive tape or a guide member of a pressure-sensitive adhesive sheet to both ends of
JP-A-333457 and JP-A-7-187435 disclose a method of adhering a reinforcing tape to which an elastomer is adhered to both ends in the width direction of the belt as a belt running guide member.

FIG. 5A is a cross-sectional view showing an example of a countermeasure for preventing the endless belt from running offset in a conventional image forming apparatus.
And a partially enlarged view (b) of FIG.

[0007] As shown in FIG.
A tape-like rubber running guide member 106 is attached to the end of the inner peripheral surface 100a of the endless belt 100 over the entire inner periphery of the endless belt 100, and a concentric engagement plate 105 is attached to the end 101a of the roll 101. ing. The endless belt 100 is provided at the inner end 106a of the travel guide member 106.
The endless belt 100 is configured to run in a state of contact with the outer end surface 105a of the engagement plate 105 so as to prevent the endless belt 100 from running sideways or meandering.

Further, Japanese Patent Application Laid-Open No. 2-27383 discloses that
An image forming apparatus in which a countermeasure for preventing the endless belt from running as described below is shown.

FIG. 6 is a cross-sectional view (a) showing another example of a countermeasure for preventing the endless belt from running offset in a conventional image forming apparatus and a partially enlarged view (b) of FIG.

[0010] As shown in FIG.
A guide groove 103 is formed at an end of the roll 101 that supports the endless belt 100.
At a position corresponding to the guide groove 103, a tape-like guide rib 104 made of a rubber member or the like is attached over the entire inner circumference of the belt. The guide rib 104 is an endless belt 1
It is formed of a material having a friction coefficient smaller than the friction coefficient of 00. In this image forming apparatus, the guide groove 103 of the roll 101 guides the guide rib 104 while the endless belt 10
By supporting 0, the endless belt 100 is configured to prevent a sideward running or meandering.

Further, Japanese Patent Application Laid-Open No. 5-333707 discloses an image forming apparatus in which the following measures are taken to prevent the endless belt from running off.

FIG. 7 is a cross-sectional view (a) showing another example of a countermeasure for preventing the endless belt from running offset in a conventional image forming apparatus and a partially enlarged view (b) of FIG.

[0013] As shown in FIG.
On one side end of the inner peripheral surface 200a, a tape-shaped bias guide 202 having a predetermined width is attached over the entire inner periphery of the belt. A disc-shaped offset guide restricting member 204 is provided at a distance substantially equal to the width of the offset guide tool 202. The bias guide regulating member 204 is supported by a bearing 206 via a spring 205. In this image forming apparatus, the offset guide member 202 provided on the inner peripheral surface 200a of the endless belt 200 includes:
By being sandwiched and guided between the end face 203a of the support roll 203 and the end face 204a of the offset guide regulating member 204, the endless belt 200 is configured to prevent the offset travel and meandering.

[0014]

However, these image forming apparatuses have the following problems.

As in the image forming apparatus shown in FIG. 5A, the inner end 106a of the traveling guide member 106 provided on the endless belt 100 is connected to the outer end surface 1 of the engagement plate 105.
In the method in which the guide is performed in a state in which the endless belt is in contact with the traveling guide member 106, as shown in FIG.
The tension F in the direction of the arrow perpendicular to the surface of the endless belt 100 is applied to the endless belt 100 at the boundary Q.
The end of 0 is bent inward. Since the stress is concentrated on the inwardly bent portion, the portion is easily damaged, and furthermore, the side surface 106a of the traveling guide member 106 does not come into surface contact with the outer end surface 105a of the engagement plate 105, and the vehicle runs on the roll 101. Inconveniences such as becoming easy occur.

In the method of guiding the guide ribs 104 provided at the end of the endless belt 100 by the guide grooves 103 of the roll 101 as in the image forming apparatus shown in FIG. There is a problem that the 104 can easily get on the drive roll 101.

Further, as in the image forming apparatus shown in FIG. 7A, the offset guide member 202 provided on the endless belt 200 is brought into contact with the end surface 204a of the offset guide regulating member 204 on the support roll 203 side. In the method in which the belt is guided in the folded state, as shown in FIG.
Since the tension F in the direction of the arrow perpendicular to the surface of the endless belt 200 is applied to the boundary portion Q corresponding to the contact surface between the end surface of the endless belt 200 and the end surface 203a of the endless belt 200, It is bent inward, and this part is easily damaged, and furthermore, the offset guide member 202
The inner end 202a of the support roller 203 easily rides on the support roll 203.

In the image forming apparatus shown in FIG. 6 or 7, a combination of the guide rib 104 and the guide groove 103 (see FIG. 6) or a combination of the one-side guide member 202 and the one-side guide regulating member 204 (see FIG. 6). In the offset prevention method according to FIG. 7), the guide rib 104 or the offset guide member 202 provided on the endless belt side is used to guide the endless belt by the guide groove 103 or the offset guide regulating member 204 provided on the roll side. Although the movement of the roll in the axial direction is restricted to prevent the side running or meandering, the endless belt side member comes into direct contact with the roll side member. When a biasing force that causes the belt to move in the axial direction of the roll is generated, a reaction force generated against the biasing force is generated by a member on the endless belt side, that is, a guide. Bed 104 or offset guide tool 20
2 and so on. When this state continues for a long period of time, as shown in FIGS. 6B and 7B, the boundary between the endless belts 100 and 200 and the guide rib 104 or the bias guide 202 (including the adhesive surface). ) Stress is intensively applied to Q, cracks or the like are generated in the stress concentrated portion, and the guide rib 104 or the biasing guide member 202 is peeled off from the endless belts 100, 200, or the endless belts 100, 200 themselves There is a problem that the endless belts 100 and 200 themselves become unusable eventually, being distorted or broken. Such a phenomenon is generally caused by the fact that the intermediate transfer belt and the paper transfer belt are formed of an extremely thin endless belt of 0.3 mm or less.

Further, if there are distortions of members such as the traveling guide member 106, the guide rib 104, and the biasing guide member 202 provided on the endless belts 100 and 200 side, or distortion of fixing to the belt, these distortions cause the distortion. Fine meandering is likely to occur. In addition, the dimensional accuracy of the traveling guide member 106, the guide rib 104, the offset guide member 202, and the like is poor, deformation of these members due to wear occurs,
The traveling guide member 1 is formed by, for example, a state in which the belt end is slightly bent downward at the boundary portion Q by the tension in the belt traveling direction caused by the tension of the belt.
06, the guide rib 104, the one-sided guide 202, etc. may ride on the roll.

The endless belt 100 is also used when the depth of the guide groove 103 (see FIG. 6) is too deep and there is a large gap between the bottom surface of the guide groove 103 and the lower surface of the guide rib 104. The guide rib 104 is bent toward the inside of the guide groove 103 by the weight of the guide rib 104, and the guide rib 104 is
There are times when you get on top.

In view of the above circumstances, the present invention provides an endless belt that is stretched by a plurality of rolls and that circulates and that is prevented from running side-by-side or meandering, and a failure caused by using the endless belt. It is an object of the present invention to provide an image forming apparatus that is low in running cost and low in running cost.

[0022]

A first endless belt according to the present invention which achieves the above object is an endless belt which is stretched by a plurality of rolls and circulates in a predetermined direction. An endless base having a pair of protrusions extending by a predetermined length beyond the base, and a pair of protrusions, formed on the roll-side surface, contacting each end of the roll, and A pair of ribs made of a tape-like elastic member extending in the predetermined direction, which regulates the relative position of the roll in the axial direction, and opposite ends of the end of the endless belt in the width direction opposite to the surface on which the ribs are formed. And a pair of resin tapes having a width of at least twice the width of the ribs and having a reinforcing material woven therein and extending in the predetermined direction.

Here, the reinforcing material may be cloth, and the reinforcing material may be glass fiber.

The second object of the present invention to achieve the above object is as follows.
The endless belt is an endless belt that is stretched by a plurality of rolls and circulates in a predetermined direction, wherein the endless base has a pair of protrusions extending a predetermined length beyond both sides from both ends in the axial direction of the roll, and A pair of protrusions, formed on the roll-side surface, are in contact with both ends of the roll to regulate the relative position of the roll in the axial direction with respect to the roll, and are tape-shaped extending in the predetermined direction. A pair of ribs made of an elastic member, and a ridge extending in the predetermined direction, which is formed in a widthwise convex shape and formed on a surface opposite to a surface on which the rib is formed at both ends in a width direction of the endless belt. And a pair of resin tapes having a portion extending in the predetermined direction.

The rib has a JIS-A hardness of 50 °.
It is preferable that it is made of an elastic member having an angle of 90 ° or less.

The base has a Young's modulus of 30,000.
It may be made of a resin material of kg / cm ² or more, and it is also preferable that the base is made of a polyimide resin.

The first object of the present invention for achieving the above object is as follows.
In the process of forming an image on a sheet by forming a toner image and finally transferring and fixing the toner image on a sheet, the image forming apparatus is stretched over a plurality of rolls and circulated in a predetermined direction. In an image forming apparatus using a moving endless belt, the endless belt has an endless base having a pair of protrusions extending a predetermined length beyond both sides from both ends in the axial direction of the roll, and the pair of protrusions. A tape-shaped elastic member extending in the predetermined direction, which is formed on the roll-side surface of the portion and contacts each end of the roll to regulate the relative position of the roll in the axial direction with respect to the roll. And a pair of ribs formed at both ends in the width direction of the endless belt, formed on the surface opposite to the surface on which the ribs are formed, and having a width of at least twice the width of the ribs therein. Reinforcement material woven Mareta, characterized in that it is intended that a pair of resin tapes extending in the predetermined direction.

The second object of the present invention to achieve the above object is as follows.
In the process of forming an image on a sheet by forming a toner image and finally transferring and fixing the toner image on a sheet, the image forming apparatus is stretched over a plurality of rolls and circulated in a predetermined direction. In an image forming apparatus using a moving endless belt, the endless belt has an endless base having a pair of protrusions extending a predetermined length beyond both sides from both ends in the axial direction of the roll, and the pair of protrusions. A tape-shaped elastic member extending in the predetermined direction, which is formed on the roll-side surface of the portion and contacts each end of the roll to regulate the relative position of the roll in the axial direction with respect to the roll. And a pair of ribs formed at both ends in the width direction of the endless belt, formed on the surface opposite to the surface on which the ribs are formed, and formed with a convex portion in the width direction and a ridge extending in the predetermined direction. Have, Wherein the serial in which and a pair of resin tapes extending in a predetermined direction.

[0029]

Embodiments of the present invention will be described below.

The first endless belt and the second endless belt of the present invention form an image on a sheet by forming a toner image and finally transferring and fixing the toner image on the sheet. First and second aspects of the invention having a process
Is an endless belt that is stretched around a plurality of rolls and circulates and moves in a predetermined traveling direction, used in an image forming process in the image forming apparatus. Differences between the first endless belt and the second endless belt of the present invention will be described later.

Further, the first image forming apparatus of the present invention forms the toner image, and finally transfers and fixes the toner image on the sheet, thereby forming the image on the sheet. An image forming apparatus using a first endless belt, a second image forming apparatus according to the present invention forms a toner image, and finally transfers and fixes the toner image on a sheet to fix the sheet. The second step of the present invention is to form an image on
Is an image forming apparatus using the endless belt.

The first and second image forming apparatuses of the present invention are not limited to a special type of image forming apparatus.
For example, a mono-color image forming apparatus in which only a single-color toner is stored in a developing device, or intermediate transfer by repeating primary transfer of toner images of different colors formed on a plurality of photosensitive drums sequentially to an intermediate transfer belt An intermediate transfer type color image forming apparatus that forms a multi-toner image on a belt, and a plurality of photosensitive drums equipped with a developing device for each color are arranged in series on a paper transport transfer belt, and are placed on each photosensitive drum. The present invention is applied to a tandem-type color image forming apparatus or the like in which formed toner images of different colors are sequentially superimposed and transferred on a sheet carried on a sheet conveying transfer belt to form a multiple toner image on the sheet. Can be.

FIG. 1 is a schematic configuration diagram of an intermediate transfer type color image forming apparatus using the first endless belt or the second endless belt of the present invention as an intermediate transfer belt.

As shown in FIG. 1, in this color image forming apparatus, a process of forming an image on paper P by forming a toner image and finally transferring and fixing the toner image on paper P An intermediate transfer belt 2 stretched around a plurality of rolls 21, 22, 23, 24 and circulating in the direction of arrow B;
That is, the first endless belt or the second endless belt of the present invention is used. Details of the endless belt will be described later.

In this color image forming apparatus, an electrostatic latent image is formed on the surface, the photosensitive drum 1 carrying the electrostatic latent image and rotating in the direction of arrow A, and the electrostatic latent image formed on the photosensitive drum 1. The developing devices 5, 6, which develop the latent images with Bk (black), Y (yellow), M (magenta), and C (cyan) toners to form toner images t of the respective colors on the photosensitive drum 1. 7, 8, the intermediate transfer belt 2 receiving the primary transfer of the toner image t from the photosensitive drum 1 at the primary transfer position T1, the conductive roll 25 for applying a transfer bias for the primary transfer, and the intermediate transfer belt 2. A bias roll 3 and a backup roll 22 for secondary transfer of the multiple toner image formed by multiple transfer onto the paper P at a secondary transfer position T2, and a cleaning brake for removing the deposit on the bias roll 3 27, backup roll 22
Rolls 21, 23, 24 for applying a voltage to the intermediate transfer belt 2, a paper tray 14 for storing the paper P, and a sheet P taken out from the recording paper bundle 15 in the paper tray 14 to perform a secondary operation. It includes a pick-up roll 16 and a feed roll 17 for supplying to the transfer position T2, a separating claw 13 for separating the sheet P from the intermediate transfer belt 2, and a belt cleaner 9 for removing the deposit on the intermediate transfer belt 2.

Next, the operation of the image forming apparatus will be described.

As shown in FIG. 1, after the surface of the photosensitive drum 1 rotating in the direction of arrow A is uniformly charged by a charging device (not shown), image writing means such as a laser writing device is used. (Not shown), the first surface of the photosensitive drum 1 is
An electrostatic latent image of a color (for example, Bk) is formed. This electrostatic latent image is developed with Bk toner by the Bk developing device 5 and is visualized to form a toner image t. The toner image t reaches the primary transfer position T1 where the conductive roll 25 is arranged with the rotation of the photosensitive drum 1, and the toner image t is applied by applying an electric field of the opposite polarity to the toner image t by the conductive roll 25. Is primarily transferred onto the intermediate transfer belt 2 electrostatically.

Hereinafter, similarly, the Y toner image t of the second color, the M toner image t of the third color, and the C toner image t of the fourth color
Are sequentially formed on the surface of the photosensitive drum 1 and are superposed and transferred on the transfer belt 2 to form a multi-toner image on the intermediate transfer belt 2. The multiplex toner image formed on the intermediate transfer belt 2 is rotated by the intermediate transfer belt 2 in the direction of arrow B, and the bias roll 3 and the backup roll 22 are rotated.
Is transported to the secondary transfer position T2 where is disposed.

The paper P is picked up one by one from a bundle of recording papers 15 stored in a paper tray 14 by a pickup roll 16, and is fed to a feed roll in synchronization with the timing at which the multiple toner image is transported to the secondary transfer position T 2. 17, the sheet is fed to the secondary transfer position T2. The multi-toner image sandwiched between the intermediate transfer belt 2 and the paper P is pressed and conveyed by the bias roll 3 and the backup roll 22,
And the electrostatic repulsion by the transfer voltage having the same polarity as the polarity of the toner image applied by the electrode roll 26,
Transcribed above.

The paper P on which the multiple toner image has been transferred is separated from the intermediate transfer belt 2 by moving the peeling claw 13 at the retracted position to the operating position until the primary transfer of the final toner image is completed. The toner image is conveyed to a non-fixing device and subjected to a pressure / heat treatment to fix the toner image to a permanent image.

The intermediate transfer belt 2 on which the secondary transfer of the multi-toner image to the sheet P has been completed is cleaned by a belt cleaner 9 provided downstream of the secondary transfer position T2 to remove the remaining toner. Prepared for the image forming cycle.

A cleaning blade 27 made of polyurethane or the like is attached to the bias roll 3 so as to be always in contact therewith, and is configured to remove foreign matters such as toner particles and paper dust adhered to the bias roll 3.

The first and second image forming apparatuses of the present invention are not limited to the intermediate transfer type color image forming apparatus shown in FIG. 1, but may be of another type such as a tandem type color image forming apparatus as shown below. The present invention can also be applied to an image forming apparatus.

FIG. 2 is a schematic configuration diagram of a tandem type color image forming apparatus using the first endless belt or the second endless belt of the present invention as a paper transfer belt.

As shown in FIG. 2, in this color image forming apparatus, a process of forming an image on paper P by forming a toner image and finally transferring and fixing the toner image on paper P The paper transport transfer belt 30 stretched around a plurality of rolls 31, 32, 33, and 34 and circulating in the direction of arrow B, that is, the first endless belt and the second endless belt of the present invention are used.

On the paper transport transfer belt 30, Bk
(Black), Y (yellow), M (magenta), C
Four image forming units 3 corresponding to each color of (cyan)
5k, 35y, 35m, and 35c are arranged in series. Each image forming unit includes a photosensitive drum 36k, 36y, 36m, 36c that rotates in the direction of arrow A, and an electrostatic latent image forming device 37 that forms an electrostatic latent image on each photosensitive drum.
k, 37y, 37m, 37c, and developing units 38k, 38y, which develop the electrostatic latent images on the respective photosensitive drums, which respectively store the toners of the respective colors, to form toner images of the respective colors.
38m, 38c; chargers 39k, 39y, 39m, 39c for uniformly charging the surface of each photoconductor drum; and photoconductor cleaner 40 for removing toner remaining on each photoconductor drum.
k, 40y, 40m, 40c, and the paper transfer belt 30
Disposed at a position facing each photosensitive drum via
Transfer units 41k, 41y, 41m, and 41c for transferring the toner images formed on the respective photosensitive drums to the sheet P are provided.

Further, in addition to these, a static eliminator 42 for removing the electric charge of the paper transport transfer belt 30, a belt cleaner 43 for removing the deposits on the paper transport transfer belt 30, and fixing the toner image transferred to the paper P A fixing device 44 is provided.

In this color image forming apparatus, first, a Bk toner image from the image forming unit 35k of the first color is transferred onto a sheet P carried on the sheet transfer belt 30 and conveyed in the direction of arrow B. Next, the second color image forming unit 3 is placed on the Bk toner image transferred onto the sheet P.
The Y toner images from 5y are transferred in a superimposed manner, and subsequently, the M and C toner images of the third and fourth colors are sequentially superimposed and transferred to form a multi-toner image on the paper P. The multi-toner image formed on the paper P is finally fixed by the fixing device 44 to form a color image.

Next, an endless belt used as an intermediate transfer belt or a sheet conveyance transfer belt of each of the above-described image forming apparatuses of this embodiment will be described.

FIG. 3 is a view showing an embodiment of the first endless belt of the present invention used in the image forming apparatus of this embodiment.

As shown in FIG. 3, a first endless belt 51 of the present invention includes an endless base 51a having a pair of projecting portions 51b extending a predetermined length from both ends in the axial direction of a roll 52 beyond both sides thereof. Both ends 5 of the roll 52 formed on the surface 51c of the pair of protrusions 51b on the roll 52 side.
2a, a pair of ribs 53 made of a tape-shaped elastic member extending in the running direction of the belt and regulating the relative position of the roll in the axial direction with respect to the roll 52; Surface 5 on which rib 53 is formed
A pair of resin tapes 54 formed on the surface 51d opposite to 1c and having a width W2 that is at least twice the width W1 of the rib 53 and in which a reinforcing material is woven is provided.

As described above, the width W of the rib 53 is twice or more than the width W1 of the rib 53 at the protrusions 51b at both ends in the width direction of the endless belt 51.
By providing the resin tape 54 having
The boundary Q between the endless belt 3 and the endless belt 51 is reinforced by the reinforcing tape, the durability against the stress concentrated on the boundary Q is improved, the bending becomes difficult, and the reinforcing tape 54 is formed.
By providing a resin tape in which a reinforcing material having a higher Young's modulus and less deformation due to stress than a conventional resin tape is woven, or a resin tape in which the reinforcing material is laminated, the belt end portion at the boundary portion Q is formed. Bending is prevented and the belt end is reinforced, so that the boundary Q
The endless belt is less liable to bend because the durability against stress concentrated on the belt is improved. In addition, the belt end side is the boundary portion Q.
Is prevented from being slightly bent downward, and the problem that the rib 53 rides on the roll 52 is also solved.

In this embodiment shown in FIG. 3, concentric engagement plates 55 are attached to both ends 52a of the roll 52, and the ends 52a come into contact with the ribs 53 via the engagement plates 55. ing. The engaging plate 55 is made of a highly lubricating material such as polyacetal, and is a member for reducing friction between the both ends 52 a of the roll 52 and the rib 53. is not.

As the reinforcing tape 54, an acetate cloth,
An adhesive tape formed by laminating nonwoven fabrics such as cotton cloth and polyester nonwoven fabric, and a laminated adhesive tape formed by laminating crepe paper, flat paper, nomex paper, and the like can be given. Specifically, a 0.23 mm-thick acetate cloth adhesive tape No. 5 manufactured by Nitto Kogyo Co., Ltd. obtained by laminating an acrylic adhesive on an acetate nonwoven fabric, and a 0.15 mm thick ( stock)
530F manufactured by Teraoka Seisakusho, 670 manufactured by Teraoka Seisakusho Co., Ltd.
S, No. 340 manufactured by Nitto Kogyo Co., Ltd., 570S manufactured by Teraoka Seisakusho Co., Ltd. made by laminating acetate cloth and polyester film, 540S manufactured by Teraoka Seisakusho Co., Ltd. made by laminating glass fiber and silicone-based adhesive, Nitto Industrial Co., Ltd.
No. 185 and the like.

As a reinforcing material for the reinforcing tape 54, gas is used.
Lath fibers can also be used. That is, endless belt
A resin tape made by laminating glass fibers on both ends of the surface
It may be provided. Tape base made of laminated glass fiber
Young's modulus is 500kg / cm ^TwoThat is more than the conventional elasticity
Young's modulus of base material of polyester adhesive tape having
2kg / cm^TwoMore than 25 times larger than endless belt
The effect of preventing bending of the end is great, and the endless belt
Edge slightly bent down at boundary Q
Rib 53 rides on roll 52
It also has a great effect of preventing shaking. Glass fiber laminated resin
Silicone resin used as adhesive for tape
540S manufactured by Teraoka Manufacturing Co., Ltd., N manufactured by Nitto Kogyo Co., Ltd.
o. 185 and the like.

Next, the second endless belt of the present invention will be described.

FIG. 4 is a view showing an embodiment of the second endless belt of the present invention used in the image forming apparatus of this embodiment.

As shown in FIG. 4, the second endless belt 61 of the present invention includes an endless base 61a having a pair of protrusions 61b extending from both ends in the axial direction of the roll 62 by a predetermined length over both sides. The belt travels by contacting both ends 62a of the roll 62 formed on the surface 61c of the pair of protrusions 61b on the roll 62 side to regulate the relative position of the roll to the roll 62 in the axial direction. A pair of ribs 63 made of a tape-like elastic member extending in the direction
And a ridge 61e formed on a surface 61d opposite to the surface 61c on which the ribs 63 are formed at both ends in the width direction of the endless belt 61, and having a convex shape in the width direction and extending in the running direction of the belt.
And a pair of resin tapes 64 extending in the running direction of the belt.

As described above, the resin tape 64 having the peak 61e extending in the running direction of the belt and having a convex shape in the width direction is laminated on the surfaces 61d at both ends in the width direction of the endless belt 61, so that the boundary portion is formed. The belt end can be prevented from bending downward at the position Q. As a material for the resin tape 64, a urethane resin, a silicon resin, or the like can be used.

Next, the rib 5 of the first endless belt of the present invention will be described.
3 (see FIG. 3) and the ribs 63 (see FIG. 4) of the second endless belt will be described.

While the endless belt is being driven, a biasing force is generated to move the endless belt in the width direction, and the same strength stress (reaction force) generated against the biasing force is applied to the rib. The reaction force is directly applied to the ribs 53 and 63, but by using a material for the ribs 53 and 63 as an elastic member, this reaction force is
3, 63 can be dispersed and absorbed inside the members. From this point of view, the material of the ribs 53 and 63 is JIS
It is desirable to use an elastic member having a -A hardness of 50 ° to 90 °, and a JIS-A hardness of 60 ° to 80 °
The following is preferred. As the elastic member having a JIS-A hardness of 50 ° or more and 90 ° or less, one or two types of rubber materials such as silicone rubber, fluorine rubber, urethane rubber, EPDM, NBR, CR, chlorinated polyisoprene, hydrogenated polybutadiene, and butyl rubber are used. A material obtained by blending the above can be used.

The above-mentioned reaction force intensively applies a load to the boundary portion Q (including the bonding surface) between the ribs 53 and 63 and the endless belts 51 and 61. In the case where an adhesive having elasticity is used, the above-described reaction force can be dispersed and absorbed to some extent inside the adhesive member.
The problem of peeling off from the first and the first 61 can be solved.

Next, the base 51a (see FIG. 3) of the first endless belt and the base 6 of the second endless belt of the present invention will be described.
1a (see FIG. 4) will be described.

The materials of the bases 51a and 61a are
And Young's modulus 30,000 kg / cm ^TwoThe above resin materials
By using this, the conventional Young's modulus of 24000 kg /
cm^TwoAbout polycarbonate and Young's modulus 18000
kg / cm^TwoETFE (Ethylene tetrafluoroe
When using a thermoplastic resin material such as (Tylene copolymer)
Caused by the tension between the endless belt rolls
Due to the tension in the belt running direction
In Q, it may be slightly bent downward.
Is prevented and the rib gets on the roll
The problem is solved.

Such a Young's modulus of 30,000 kg / cm
Examples of the ^two or more resin materials include a polyimide resin and polyetheretherketone (PEEK). A polyimide resin material having a high Young's modulus is particularly preferable as the base material of the endless belt. As the polyimide resin material, Kapton H manufactured by DuPont
A, etc., polypyromellitic imide-based imide resin material, Ube Industries, Ltd., Ubilex S, etc. polybiphenyltetracarboxylic acid imide-based resin material, Ube Industries, Ltd., Upilex R, Mitsui Toatsu Chemicals (stock)
And polybenzophenone tetracarboxylic acid imide acid-based resin materials such as LARC-TPI (thermoplastic polyimide resin). These are all 35
It has a Young's modulus of 000 kg / cm ² or more and is preferable as a base material of an endless belt. For example, when carbon black is dispersed in a polybiphenyltetracarboxylic acid imide-based resin material such as Upilex S manufactured by Ube Industries, Ltd., the Young's modulus is 62000 kg / cm ² , and the belt base has a thickness of 70 μm to 100 μm. The mechanical properties as a base can be satisfied.

Further, the endless belt of the present invention is connected to an intermediate transfer bell.
In the case of using it as a⁹Ωc
1 x 10 or more¹⁴Ωcm or less is desirable.
No. Volume resistivity is 1 × 10⁹Intermediate rotation if less than Ωcm
Holds the charge of the unfixed toner image transferred to the photo belt
Electrostatic repulsion between toners due to the stop of electrostatic force
Force or fringe field force near the image edge
Blur phenomenon where toner scatters around and image defects
There is a risk of becoming. On the other hand, the volume resistivity is 1 × 10 ¹⁴Ωcm
Exceeds the limit, the electrostatic force that holds the charge increases and
The multi-toner image on the intermediate transfer belt was transferred to paper
Because the charge remains on the intermediate transfer belt even after
It is necessary to provide a static elimination mechanism upstream of the device.

The volume resistivity of the endless belt is 1 × 10 ⁹ Ωc
m or more and 1 × 10 ¹⁴ Ωcm or less, if necessary, as a conductive agent, a metal or alloy such as carbon black, graphite, aluminum, and copper alloy; tin oxide;
One or more fine powders of metal oxides such as zinc oxide, potassium titanate, tin oxide-indium oxide, and tin oxide-antimony oxide composite oxide are used.
Of these, it is preferable to use carbon black from the viewpoint of cost.

[0068]

Next, a first embodiment of the first endless belt of the present invention will be described.
-Example 6 of the second endless belt and Example 7, and the production method for Comparative Examples 1 to 6, characteristic values of the belt,
The belt life and the like will be described.

Example 1 A thermosetting seamless belt in which carbon black was dispersed was produced as follows. Using a mixer or the like, carbon black is mixed with the polyimide U varnish-S for heat resistant film manufactured by Ube Industries, Ltd. This mixed solution is poured into a cylindrical mold and subjected to centrifugal molding while heating. The mold is released in a semi-cured state, and the belt obtained by removing the mold is covered with an iron core, heated to 450 ° C., and fully cured (imidization reaction) to have a surface resistivity of 10 ¹² Ω / □ and a thickness of 10 ¹² Ω / □. 8
A 0 μm seamless belt was obtained.

Next, a 5 mm wide and 15 mm high JIS-
A one-part cold-setting adhesive, Super XN, manufactured by Cemedine, as an adhesive on a urethane resin (A type hardness TR100-70 (trade name) manufactured by Tigers Co., Ltd.) having an A hardness of 70 °
o. A coating was applied on the inner peripheral surface at both ends in the width direction of the seamless belt having a thickness of 80 μm to form a rib.

Further, on the outer peripheral surface of both ends in the width direction of the seamless belt, an acetate cloth and an acrylic adhesive are laminated as a resin tape with a width of 10 mm and a thickness of 230 mm.
μm acetate cloth adhesive tape No. 1 manufactured by Nitto Denko Corporation.
5 to obtain a first endless belt of the present invention.

[Example 2] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
A 10 mm wide, 180 μm thick Nitto Denko Corporation made by laminating a silicone adhesive on glass fiber as a resin tape on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt having a urethane resin rib having a height of 15 mm. Composite adhesive tape No. 188UL was applied to obtain a first endless belt of the present invention.

Example 3 The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
A 10 mm wide, 230 μm thick Nitto Denko Corporation made by laminating an acetate cloth and an acrylic adhesive as a resin tape on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt having a urethane resin rib having a height of 15 mm. Acetate cloth adhesive tape No. 5 to obtain a first endless belt of the present invention.

[Example 4] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
A 15 mm wide, 180 μm thick product made by Nitto Denko Corp., made by laminating a silicone-based adhesive on glass fiber as a resin tape on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt having a urethane resin rib having a height of 15 mm. Composite adhesive tape No. 188UL was applied to obtain a first endless belt of the present invention.

Example 5 A 150-μm-thick thermoplastic polyimide resin seamless belt obtained by the same method as that shown in Example 1 had a width of 5 mm and a height of 5 mm on the inner circumferential surface at both ends in the width direction. JIS-A hardness of 15mm 70 °
Urethane resin (Typeren TR1 manufactured by Tigers Co., Ltd.)
(00-70 (trade name)), a one-part cold-setting adhesive Super X No. 8008 manufactured by Cemedine was applied as an adhesive so as not to protrude from the adhesive surface, and a rib was formed. Next, on the outer peripheral surface of both ends in the width direction of the polyimide seamless belt, an acetate cloth and an acrylic adhesive material having a width of 10 m are laminated as a resin tape.
m, acetate cloth adhesive tape No. 230 m thick, manufactured by Nitto Denko Corporation. 5 to obtain a first endless belt of the present invention.

[Embodiment 6] This embodiment is the same as Embodiment 5 except that the width of the resin tape in the endless belt shown in Embodiment 5 is changed to 15 mm.

[Embodiment 7] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Embodiment 1 was 5 mm wide.
A polyimide seamless belt having a urethane resin rib with a height of 15 mm has a width of 20 m on the outer peripheral surface at both ends in the width direction.
m, a pair of urethane resins extending in the belt running direction, having a width of 0.2 mm at the width direction end and a maximum thickness of 0.5 mm at the center in the width direction, having a convex portion in the width direction and having a ridge extending in the belt running direction. The tape was coated with a one-part cold-setting adhesive, Super X No. 8008 manufactured by Cemedine so as not to protrude from the adhesive surface, and was adhered to form a resin tape, thereby obtaining a second endless belt of the present invention.

[Comparative Example 1] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm in width.
A width of 8.5 mm is formed on the outer peripheral surface at both ends in the width direction of a polyimide seamless belt having a urethane resin rib having a height of 15 mm.
mm, polyester adhesive tape No. 80 manufactured by Nitto Denko Corporation. The endless belt of Comparative Example 1 was affixed with 31C.

[Comparative Example 2] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
A polyimide seamless belt having a urethane resin rib with a height of 15 mm has a width of 5 m on the outer peripheral surface at both ends in the width direction.
m, polyester adhesive tape No. 80 manufactured by Nitto Denko Corporation. The endless belt of Comparative Example 2 was affixed with 31C.

Comparative Example 3 A 150-μm-thick thermoplastic polyimide resin seamless belt obtained by the same method as that shown in Example 1 had a width of 5 mm and a height of 5 mm on both inner circumferential surfaces. JIS-A hardness of 15mm 70 °
Urethane resin (Typeren TR1 manufactured by Tigers Co., Ltd.)
(00-70 (trade name)), a one-part cold-setting adhesive Super X No. 8008 manufactured by Cemedine was applied as an adhesive so as not to protrude from the adhesive surface, and a rib was formed. Next, a width of 10 mm and a thickness of 80 μm were formed on the outer peripheral surfaces of both ends in the width direction of the polyimide seamless belt.
m of Nitto Denko Corporation polyester adhesive tape No. 3
The endless belt of Comparative Example 3 was affixed with 1C.

[Comparative Example 4] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
Nitto Denko Co., Ltd. polyester adhesive tape No. 8.5 mm wide and 80 μm thick on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt to which a rib of urethane resin having a height of 15 mm and a JIS-A hardness of 85 ° is adhered. . The endless belt of Comparative Example 4 was affixed with 31C.

[Comparative Example 5] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
Nitto Denko Corporation polyester adhesive tape No. 8.5 mm wide and 80 μm thick on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt to which a rib of urethane resin having a height of 15 mm and JIS-A hardness of 45 ° is adhered. . The endless belt of Comparative Example 5 was affixed with 31C.

[Comparative Example 6] The inner peripheral surface at both ends in the belt width direction obtained by the method shown in Example 1 was 5 mm wide.
A polyester adhesive tape No. of Nitto Denko Corporation with a width of 8.5 mm and a thickness of 80 μm is provided on the outer peripheral surface of both ends in the width direction of a polyimide seamless belt to which a rib of urethane resin having a height of 15 mm and JIS-A hardness of 70 ° is adhered. . The endless belt of Comparative Example 6 was affixed with 31C.

Tables 1 and 2 show the characteristic values of the endless belts of Examples 1 to 7 and Comparative Examples 1 to 6, and the belt life when a running test was conducted at a belt tension of 5 kgf and a process speed of 260 mm / sec. It is the table shown.

[0085]

[Table 1]

[0086]

[Table 2]

As shown in Table 1, the endless belt of the present invention (Examples 1 to 7) has a belt life of 2000 kcycle or more, which is significantly improved as compared with the endless belts of Comparative Examples 1 to 6. You can see that it is done.

In Comparative Example 1, an 8.5 mm wide resin tape made of polyester was attached to the outer peripheral surface of both ends in the width direction of the seamless belt made of polyimide resin. However, when the width of the resin tape is less than twice the width of the ribs as described above, the reinforcing effect of the resin tape is negligible. Not enough.

[0089]

As described above, according to the endless belt of the present invention, an endless belt such as an intermediate transfer belt or a paper transport transfer belt stretched and rotated by a plurality of rolls is shifted or meandering. The problem of breaking on a drive roll or a support roll or the like is solved, and the life of the endless belt can be greatly extended.

Further, by using the endless belt as an intermediate transfer belt or a paper transfer belt of an image forming apparatus, an image forming apparatus with less failure and low running cost can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an intermediate transfer type color image forming apparatus using a first endless belt or a second endless belt of the present invention as an intermediate transfer belt.

FIG. 2 is a schematic configuration diagram of a tandem-type color image forming apparatus using a first endless belt or a second endless belt of the present invention as a sheet conveyance transfer belt.

FIG. 3 is a diagram illustrating an embodiment of the first endless belt of the present invention used in the image forming apparatus of the present embodiment.

FIG. 4 is a diagram illustrating one embodiment of a second endless belt of the present invention used in the image forming apparatus of the present embodiment.

FIGS. 5A and 5B are a cross-sectional view and a partially enlarged view showing an example of a countermeasure for preventing the endless belt from running offset in a conventional image forming apparatus.

FIGS. 6A and 6B are a cross-sectional view and a partially enlarged view showing another example of a countermeasure for preventing the endless belt from running in a conventional image forming apparatus.

FIGS. 7A and 7B are a cross-sectional view and a partially enlarged view illustrating another example of a countermeasure for preventing the endless belt from running offset in a conventional image forming apparatus.

[Explanation of symbols]

 Reference Signs List 1 photosensitive drum 2 intermediate transfer belt 3 bias roll 5, 6, 7, 8 developing device 9 belt cleaner 13 peeling claw 14 paper tray 15 recording paper bundle 16 pickup roll 17 feed roll 21, 23, 24 roll 22 backup roll 25 conductive Roll 26 Electrode Roll 27 Cleaning Blade 30 Paper Transfer Belt 31, 32, 33, 34 Roll 35k, 35y, 35m, 35c Image Forming Unit 36k, 36y, 36m, 36c Photoconductor Drum 37k, 37y, 37m, 37c Electrostatic Latent image forming device 38k, 38y, 38m, 38c Developing device 39k, 39y, 39m, 39c Charger 40k, 40y, 40m, 40c Photoconductor cleaner 41k, 41y, 41m, 41c Transfer device 42 Static eliminator 43 Belt cleaner 44 Fixing Reference Signs List 51 endless belt 51a base 51b protrusion 51c, 51d surface 52 roll 52a end 53 rib 54 resin tape 55 engagement plate 61 endless belt 61a base 61b protrusion 61c, 61d surface 61e ridge 62 roll 62a end 63 rib 64 resin tape REFERENCE SIGNS LIST 100 endless belt 100 a 100 a 101 roll 103 guide groove 104 guide rib 105 engaging plate 105 a outer end surface 106 running guide member 106 a inner end portion 200 endless belt 200 a inner peripheral surface 202 offset guide device 203 support roll 203 a end surface 204 offset guide regulating member 204a End face 205 Spring 206 Bearing F Tension T1 Primary transfer position T2 Secondary transfer position Q Boundary part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16G 1/00 F16G 1/00 Z 1/14 1/14 G03G 15/16 G03G 15/16

Claims (9)

[Claims] 1. An endless belt which is stretched by a plurality of rolls and circulates in a predetermined direction, comprising: a pair of endless bases having a pair of protrusions extending from both ends in the axial direction of the roll by a predetermined length over both sides; A pair of protrusions, formed on the surface on the roll side,
A pair of ribs made of a tape-like elastic member extending in the predetermined direction, contacting each end portion of the roll, and regulating a relative position of the roll in the axial direction with respect to the roll; and a width direction of the endless belt. A pair of ends, formed on the surface opposite to the surface on which the ribs are formed, having a width of at least twice the width of the ribs and having a reinforcing material woven therein, extending in the predetermined direction; An endless belt comprising: a resin tape; 2. The endless belt according to claim 1, wherein the reinforcing material is a cloth. 3. The endless belt according to claim 1, wherein said reinforcing material is glass fiber. 4. An endless belt stretched by a plurality of rolls and circulating in a predetermined direction, comprising: a pair of endless bases having a pair of protrusions extending from both ends in the axial direction of the roll by a predetermined length over both sides; A pair of protrusions, formed on the surface on the roll side,
A pair of ribs made of a tape-like elastic member extending in the predetermined direction, contacting each end portion of the roll, and regulating a relative position of the roll in the axial direction with respect to the roll; and a width direction of the endless belt. At both ends, formed on the surface on the opposite side to the surface on which the ribs are formed, of a convex shape in the width direction,
An endless belt comprising a pair of resin tapes having a ridge extending in the predetermined direction and extending in the predetermined direction. 5. The endless belt according to claim 1, wherein the rib is made of an elastic member having a JIS-A hardness of 50 ° to 90 °. 6. The base has a Young's modulus of 30,000 kg.
The endless belt according to any one of claims 1 to 4, wherein the endless belt is made of a resin material of not less than / cm ² . 7. The endless belt according to claim 1, wherein the base is made of a polyimide resin. 8. In the process of forming an image on a sheet by forming a toner image and finally transferring and fixing the toner image on the sheet, the toner image is stretched over a plurality of rolls and circulated in a predetermined direction. In an image forming apparatus using a moving endless belt, the endless belt has an endless base having a pair of protrusions extending a predetermined length beyond both sides from both ends in the axial direction of the roll, and the pair of protrusions Part, formed on the roll-side surface,
A pair of ribs made of a tape-like elastic member extending in the predetermined direction, and contacting each end of the roll to regulate an axial relative position of the roll with respect to the roll; and a width direction of the endless belt. A pair of ends, formed on the surface opposite to the surface on which the ribs are formed, having a width of at least twice the width of the ribs and having a reinforcing material woven therein, extending in the predetermined direction; An image forming apparatus comprising: a resin tape; 9. In the process of forming an image on a sheet by forming a toner image and finally transferring and fixing the toner image on the sheet, the toner image is stretched over a plurality of rolls and circulated in a predetermined direction. In an image forming apparatus using a moving endless belt, the endless belt has an endless base having a pair of protrusions extending a predetermined length beyond both sides from both ends in the axial direction of the roll, and the pair of protrusions Part, formed on the roll-side surface,
A pair of ribs made of a tape-like elastic member extending in the predetermined direction, and contacting each end of the roll to regulate an axial relative position of the roll with respect to the roll; and a width direction of the endless belt. At both ends, formed on the surface on the opposite side to the surface on which the ribs are formed, of a convex shape in the width direction,
An image forming apparatus comprising: a pair of resin tapes having a ridge extending in the predetermined direction and extending in the predetermined direction.