JP4265873B2 - Belt device and image forming apparatus having the belt device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a belt device and an image forming apparatus having the belt device.
[0002]
[Prior art]
A belt device including a belt wound around a plurality of rollers and driven to travel is widely used in various machines and devices. For example, in an image forming apparatus, a belt device having an image carrying belt for carrying an image is used, and the image carrying belt is configured as a photosensitive belt or an intermediate transfer belt. When the belt of the belt device is deteriorated or has reached the end of its life, the belt is replaced with a new belt. When replacing the belt, the belt to be replaced is removed from the plurality of rollers, and then a new belt is wrapped around the plurality of rollers and mounted. However, according to the conventional belt device, this belt replacement operation is very complicated. It was troublesome.
[0003]
[Problems to be solved by the invention]
The first object of the present invention is to provide a belt device that can remove the above-mentioned conventional drawbacks and can easily replace the belt, and to provide an image forming apparatus having the belt device. And
[0004]
[Means for Solving the Problems]
In order to achieve the first object, the present invention provides a belt device having a belt wound around a plurality of rollers, a first support member that supports all one ends of the plurality of rollers, A second support member that supports the other end portion of some of the rollers, and a third support member that supports the other end portion of the other rollers, the third support member being a second support member The first support member and the second support member are detachably fixed to a support member, and are fixed to each other via a stay in a state in which the position is adjusted by a jig, and the article is placed in an inner space of the belt. The stay also serves as a storage unit for storing the article, and the stay is used when the article is taken out from the stay and when the article is put into the stay. As a guide to guide Be possible to propose a belt device according to claim (Claim 1).
[0006]
In the belt device according to claim 1, it is advantageous that the third support member supports the other end of one roller (claim 2 ).
[0009]
Further, in the belt device according to claim 1 or 2 , it is advantageous that the belt is an image carrying belt for carrying an image (claim 3 ).
[0010]
Further, the present invention in order to achieve the second object, proposes an image forming apparatus characterized by comprising a belt device according to claim 3 (claim 4).
[0011]
In this case, the apparatus has a cleaning device that removes toner remaining on the image carrying belt after the toner image on the image carrying belt is transferred, and the article removes the toner removed from the image carrying belt by the cleaning device. is advantageously is a waste toner tank accommodating to (claim 5).
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a schematic sectional view showing an example of an image forming apparatus. The image forming apparatus is configured as a copying machine, a printer, a facsimile, or a multifunction machine having at least two of these functions. The image forming apparatus shown in FIG. 1 is a color printer that forms a full-color image. It is configured as. In the main body casing 50 of the image forming apparatus shown in FIG. 1, the developing device 12, the endless photosensitive belt 4 that is an example of an image carrying belt, and an endless intermediate that is also an example of an image carrying belt. A transfer belt 15 is provided. The photosensitive belt 4 is wound around the driving roller 1 and the driven rollers 2 and 3, and the intermediate transfer belt 15 is a cleaning facing roller 16, a primary transfer roller 17, a driving roller 18, a tension roller 19, and a secondary transfer facing roller 20. Are wound around a plurality of rollers.
[0013]
The developing device 12 is disposed so as to face the photosensitive belt portion between the driving roller 1 and the driven roller 2, and has four developments of a yellow developing device 12Y, a magenta developing device 12M, a cyan developing device 12C, and a black developing device 12BK. Has a vessel. The developing units 12Y to 12BK respectively include developing cases 13Y, 13M, 13C, and 13BK containing yellow toner YT, magenta toner MT, cyan toner CT, and black toner BKT, and a developing roller 14Y that carries and conveys the toner. , 14M, 14C, 14BK. Each of the developing devices 12Y to 12BK is supported by a driving device (not shown) so as to occupy a developing position approaching the outer peripheral surface of the photosensitive belt 4 and a retracted position separated from the outer peripheral surface.
[0014]
When the image forming operation is started, the driving roller 1 is driven to rotate in the clockwise direction, so that the photosensitive belt 4 is driven to run in the direction of arrow A, and the intermediate transfer belt 15 in contact with the photosensitive belt 4 is also moved. Driven in the direction of arrow B. At this time, the photosensitive belt 4 is uniformly charged by the charging roller 8, and the charged surface is irradiated with the light-modulated laser light L emitted from the laser writing unit 11 which is an example of an exposure apparatus, and thereby the photosensitive belt 4 is exposed to light. An electrostatic latent image is formed on the body belt 4.
[0015]
The above-described electrostatic latent image is visualized as a toner image by the first developing unit that occupies the developing position, in this example, the yellow developing unit 12Y. At this time, the other developing devices 12M to 12BK occupy the retracted position. The developing roller 14Y of the yellow developing device 12Y is in contact with the outer peripheral surface of the photoreceptor belt 4 or is opposed to the outer peripheral surface with a minute gap therebetween, and the developing roller 14Y is rotated, for example, counterclockwise. A predetermined developing bias is applied to the developing roller 14Y. As a result, the yellow toner YT carried and conveyed on the peripheral surface of the developing roller 14Y is electrostatically transferred to an electrostatic latent image, and the latent image is visualized as a yellow toner image. The yellow toner image formed on the photoconductor belt 4 is electrostatically primary transferred onto the surface of the intermediate transfer belt 15 in contact with the photoconductor belt 4 by the action of the transfer voltage applied to the primary transfer roller 17. The The transfer residual toner adhering to the outer peripheral surface of the photoreceptor belt 4 after the toner image transfer is scraped and removed by the cleaning member 22 of the cleaning device 25. The removed toner is conveyed to a waste toner container (not shown) through a pipe (not shown) and stored therein.
[0016]
Next, in the same manner as described above, a second electrostatic latent image is formed on the photosensitive belt 4, and this is visualized as a magenta toner image by the magenta developing device 12M that has occupied the developing position. The image is transferred onto the surface of the intermediate transfer belt 15 from above the yellow toner image. The surface of the photoreceptor belt after the toner image is transferred is cleaned by the cleaning device 25. In exactly the same manner, a cyan toner image and a black toner image are sequentially formed on the outer peripheral surface of the photosensitive belt 4 by the cyan developing device 12C and the black developing device 12BK, and these toner images are formed on the surface of the intermediate transfer belt 15. It is transferred onto the previously transferred toner image.
[0017]
On the other hand, a sheet feeding cassette 24 and a sheet feeding device 27 having a sheet feeding roller 26 are disposed in the lower part of the main body casing, and a transfer material P made of transfer paper, for example, is loaded on the sheet feeding cassette 24. The paper feed roller 26 rotates in contact with the upper surface of the uppermost transfer material P, whereby the uppermost transfer material P is fed in the direction of arrow C. The transferred transfer material P is conveyed upward, and is then fed between the intermediate transfer belt 15 and the secondary transfer roller 28 at a predetermined timing by the rotation of the registration roller pair 33. At this time, a transfer voltage is applied to the secondary transfer roller 28, whereby the superimposed toner images on the intermediate transfer belt 15 are collectively transferred onto the surface of the transfer material P. The transfer material to which the toner image has been transferred is conveyed further upward from the transfer portion and passes through the fixing device 29. At this time, the toner image is fixed on the surface of the transfer material by the action of heat and pressure. Subsequently, the transfer material is discharged to the paper discharge unit 30 at the top of the main body housing as indicated by an arrow D.
[0018]
Transfer residual toner adhering to the surface of the intermediate transfer belt after the toner image transfer is removed by the cleaning member 32 of the cleaning device 31. When the toner image before transfer on the intermediate transfer belt 15 passes through the cleaning member 32, the cleaning member 32 is separated from the surface of the intermediate transfer belt, and abuts on the surface of the intermediate transfer belt only when the transfer residual toner is removed. Similarly, when the toner image is transferred onto the transfer material P, the secondary transfer roller 28 also abuts on the surface of the intermediate transfer belt 15 via the transfer material, and at other times, the surface of the intermediate transfer belt And the untransferred toner image on the intermediate transfer belt 15 is prevented from being disturbed.
[0019]
As described above, the toner remaining on the image carrying belt after the toner image on the intermediate transfer belt 15, which is an example of the image carrying belt, is transferred to the transfer material is removed by the cleaning device 31. The toner is transported to the waste toner tank 5 by a toner transport device (not shown) and stored therein. The waste toner tank 5 is disposed in the inner space of the intermediate transfer belt 15. As described above, by storing the waste toner tank 5 in the space inside the intermediate transfer belt 15 that has conventionally been a dead space, the space in the main body housing 50 can be effectively used, and the image forming apparatus can be downsized. Can be achieved.
[0020]
Here, the intermediate transfer belt 15 and the plurality of rollers 16 to 20 that stretch the belt are configured as a unit belt device 6 together with a support member described below.
[0021]
FIG. 2 is a schematic side view of the belt device 6 as viewed in the direction of arrow II in FIG. In FIG. 2, the illustration of the rollers other than the rollers 16 and 18 among the plurality of rollers 16 to 20 is omitted to avoid complicating the drawing. 2 indicates the front side of the main body casing 50, R indicates the back side, and after opening the front door (not shown) of the main body casing, the unit belt device 6 is When pulled in the front side F, that is, in the front direction perpendicular to the paper surface of FIG. 1, the belt device 6 is guided by a guide rail (not shown) and pulled out to the front side. It is possible to leave from 50. Conversely, by pushing the belt device 6 in the back side R, that is, in the back direction perpendicular to the paper surface of FIG. Can be positioned and loaded.
[0022]
As can be seen from FIG. 2, the first support member 40 is located on one end side in the longitudinal direction of the plurality of rollers 16 to 20, in the illustrated example, on the back side R, and the longitudinal direction of these rollers 16 to 20. The second and third support members 41, 42 are located on the other end side, that is, the front side F. The third support member 42 is detachably fixed to the second support member 41 by an appropriate attaching / detaching means, in the illustrated example, by a screw 43 (see FIG. 3), and these support members 40, 41, 42 are connected to each other. A plurality of rollers 16 to 20 extending in parallel are supported.
[0023]
3 is a front view of the belt device 6 as viewed from the front side F. FIG. 4 is a view of the belt device 6 as viewed from the front side F with the second and third support members 41 and 42 removed. FIG. As can be seen from FIGS. 2 and 4, the first support member 40 has support holes 16 </ b> A and 17 </ b> A that respectively support one end in the longitudinal direction of all the rollers 16 to 20 that support the intermediate transfer belt 15. , 18A, 19A, and 20A are formed, and one end of each of the rollers 16 to 20 is attached to the first support member 40 via bearings 16B, 17B, 18B, 19B, and 20B fitted in these holes. Each is supported rotatably.
[0024]
As can be seen from FIGS. 2 and 3, the second support member 41 has the other end in the longitudinal direction of some of the plurality of rollers 16 to 20 in the longitudinal direction of the rollers 16, 17, 19, 20. Support holes 16C, 17C, 19C, and 20C for axial support are formed, and a support hole 18C for axially supporting the other end of the other roller 18 in the longitudinal direction is formed in the third support member 42. Has been. The other ends of the rollers 16 to 20 are connected to the second and third support members 41 and 42 via bearings 16D, 17D, 18D, 19D, and 20D fitted in the support holes 16C to 20C. Each is supported rotatably. The end portions of the rollers 16 to 20 are prevented from being detached from the supporting members by a locking ring (not shown), and the rollers can be removed from the supporting member by removing the locking rings.
[0025]
Although the form of the first to third support members 40 to 42 can be set as appropriate, in the illustrated example, these support members are configured as side plates formed in a plate shape, for example, a high plate such as a metal plate or a hard resin plate. It is made of a rigid material. The first support member 40 and the second and third support members 41 and 42 are arranged in parallel to face each other.
In the belt device 6 of this example, only the other end portion of one roller 18 is supported by the third support member 42, and the other end portions of the other rollers 16, 17, 19, 20 are the second end portions. Although supported by the support member 41, the other ends of the plurality of rollers may be supported by the third support member 42.
[0026]
The tension roller 19 among the plurality of rollers 16 to 20 is a roller that applies tension to the intermediate transfer belt 15. As shown in FIGS. 3 and 4, the bearings 19B and 19D that support each end of the roller 19 are slidably fitted into the support holes 19A and 19C, and the bearings 19B and 19D are compressed springs 44A and 44B. As a result, the tension roller 19 is pressed against the inner peripheral surface of the intermediate transfer belt 15 to apply a predetermined tension to the intermediate transfer belt 15.
[0027]
Further, the end portions of the stay 45 are fixed to the first support member 40 and the second support member 41, and these support members 40 and 41 are fixedly connected to each other via the stay 45. In the belt device 6 of this example, the stay 45 also serves as a storage unit that stores the waste toner tank 5 described above.
[0028]
The first support member 40 and the second support member 41 are respectively formed with openings 46A and 46B into which the waste toner tank 5 is slidably fitted. After the front door is opened, the belt device 6 is attached to the main body housing. When the waste toner tank 5 is pulled toward the front side F while being mounted in the body 50, the waste toner tank 5 slides toward the front side while being guided by the stay 45, and an opening 46 </ b> B formed in the second support member 41. The waste toner tank 5 can be taken out. On the contrary, when the waste toner tank 5 is fitted into the opening 46B and pushed into the rear side R, the waste toner tank 5 is guided to the stay 45 while being inserted into the opening 46A formed in the first support member 40. It is fitted and positioned and loaded at a predetermined position. In this way, the waste toner tank 5 is supported by the stay 45 and stored. As described above, the stay 45 of this example serves as a guide for guiding the waste toner tank 5 when the waste toner tank 5 is taken out from the stay 45 and when the waste toner tank 5 is inserted into the stay 45 . It also works. When the waste toner tank 5 is loaded at a predetermined position in the main body housing, the waste toner tank 5 is locked at that position by a lock device (not shown). The lock device can be unlocked and the waste toner tank 5 can be pulled out to the front as described above.
[0029]
The belt device 6 is configured as described above, and the intermediate transfer belt 15 is wound around the plurality of rollers 16 to 20 positioned in parallel to each other with moderate tension, so that the intermediate transfer belt 15 is wound as described above. The function of supporting the toner image can be performed without hindrance.
[0030]
Since the intermediate transfer belt 15 deteriorates with time, it is necessary to replace the intermediate transfer belt 15 with a new intermediate transfer belt when it reaches the end of its life. At that time, in the conventional belt device, the replacement operation of the intermediate transfer belt is very complicated. If no articles such as waste toner tanks are stored in the space inside the intermediate transfer belt, some rollers are retracted to the inside of the intermediate transfer belt, causing the intermediate transfer belt to loosen and Although it is possible to remove the transfer belt from a plurality of rollers and attach a new intermediate transfer belt, articles such as the waste toner tank 5 are accommodated in the inner space of the intermediate transfer belt 15 as in the belt device 6 of this example. If the roller is retracted inward, it interferes with the waste toner tank 5, so that it is difficult to retract the roller, and in particular, the replacement work of the intermediate transfer belt may be complicated. .
[0031]
On the other hand, in the belt device 6 of this example, the intermediate transfer belt 15 can be easily replaced as follows.
[0032]
First, the front door of the main body casing 50 is opened, the belt device 6 is pulled out to the front side F, and this is taken out of the main body casing 50. Next, the screw 43 shown in FIGS. 2 and 3 is loosened to remove the screw 43, and the third support member 42 is detached from the second support member 41 as shown in FIG. 5. At this time, one end of the roller 18 is removed from the first support member 40, and the roller 18 and the third support member 42 are both detached from the first support member 40 and the second support member 41. Then, since the intermediate transfer belt 15 that has been tensioned until then becomes loose as shown in FIG. 5, it can be easily removed from the rollers 16, 17, 19, and 20. By reverse operation, a new intermediate transfer belt can be easily wound around the plurality of rollers 16 to 20, and the belt device 6 can be pushed into the main body casing and set. Thus, even if the waste toner tank 5 is located in the inner space of the intermediate transfer belt 15, the intermediate transfer belt 15 can be replaced very easily.
[0033]
The above-described configuration can also be applied when the endless belt is formed of a belt other than the intermediate transfer belt 15, and the number of rollers around which the belt is wound can be set to an appropriate number as long as it is two or more. As described above, the belt device includes the endless belt wound around the plurality of rollers, the first support member that supports all one ends of the plurality of rollers, and the plurality of the plurality of rollers. A second support member that supports the other end portion of some of the rollers, and a third support member that supports the other end portion of the remaining other rollers. The support member 3 is detachably fixed to the second support member. With the configuration of such a belt device, the belt can be easily replaced.
[0034]
If the second and third support members are configured as a single support member, when the belt is removed, the single support member is removed from the ends of all the rollers, and the end of at least one roller is removed. The part has to be removed from the first support member, and the work has to be complicated. In the illustrated example, it is only necessary to remove the third support member 42 from the second support member 41 and to remove one end of one roller 18 from the first support member 40, and the operation is very simple. .
[0035]
Incidentally, since the plurality of rollers 16 to 20 support the intermediate transfer belt 15, the parallelism of the plurality of rollers 16 to 20 can be kept high so that an image can be correctly formed on the intermediate transfer belt. desirable. Therefore, when the belt device 6 is manufactured, before assembling the roller to the support member, the stay 45 is first fixed only to the first support member 40, and then the support hole of the first support member 40 by a jig (not shown). The first support member 40 and the second support so that the centers of 16A, 17A, 19A, and 20A and the centers of the support holes 16C, 17C, 19C, and 20C of the second support member 41 coincide with each other. The member 41 is positioned, and in this state, the stay 45 is fixed to the second support member 41, and then positioning means including positioning pins (not shown) provided on the second and third support members 41 and 42 is provided. If the third support member 42 is positioned with respect to the second support member 41 and the third support member 42 is fixed to the second support member 41 with the screw 43 in this state, the support Member 4 , It can be kept high parallelism of the rollers assembled to 41. In addition, when an external force is applied to the belt device 6, it is possible to prevent the belt device from being twisted. The first support member 40 and the second support member 41 are configured to be fixed to each other via the stay 45 in a state in which the position is adjusted by a jig.
[0036]
According to this configuration, even when the third support member 42 is detached from the second support member 41 when the belt is replaced, the rollers 16, 17, 19 supported by the first and second support members 40, 41 are used. , 20 does not go wrong, and the belt can be replaced while maintaining the parallel accuracy of the rollers.
[0037]
In the illustrated example, the third support member 42 supports only the other end of one roller 18. In other words, a large number of rollers are supported by the first and second support members 40 and 41 whose positions are adjusted with high accuracy by the jig, and the third support member 42 that is not adjusted by the jig is included in the third support member 42. Only the other end of one roller 18 is supported. For this reason, the parallel accuracy of a large number of rollers can be improved, and eventually the overall parallelism of the plurality of rollers 16 to 20 can be maintained high. In addition, when the belt is replaced, it is only necessary to remove the end of one roller from the support member, so that the belt replacement operation can be further simplified.
[0038]
Further, in the illustrated example, the waste toner tank 5 is accommodated inside the intermediate transfer belt 15, but it is also possible to configure so as to accommodate articles other than the waste toner tank. Thus, even when some article is stored in the inner space of the belt, the belt can be easily replaced as described above.
[0039]
Further, as described above, when the stay 45 also serves as a storage unit that stores articles, a dedicated storage unit for articles can be omitted, and the configuration of the belt device can be simplified.
[0040]
As described above, the present invention can also be applied to a belt apparatus including a belt other than the intermediate transfer belt. For example, the belt apparatus having a conveyance belt for conveying a transfer material or the photosensitive belt 4 shown in FIG. The present invention is also applicable to a belt device having the same. At this time, both the photoreceptor belt 4 and the intermediate transfer belt 15 are image carrying belts that carry an image. However, like the image forming apparatus illustrated, the image forming apparatus transfers the toner image on the image carrying belt. And a cleaning device that removes toner remaining on the image carrier belt, and the above-described article is a waste toner tank that contains toner removed from the image carrier belt by the cleaning device. Miniaturization of the image forming apparatus can be achieved.
【The invention's effect】
[0041]
According to the inventions according to claims 1 to 5 , the belt can be easily replaced.
[0042]
In particular, according to the first aspect of the invention, the belt can be replaced while maintaining the accuracy of the belt device, the inner space of the belt can be used effectively, and the belt can be easily replaced. . Furthermore, the structure of the belt device can be simplified.
[0043]
Moreover, according to the invention which concerns on Claim 2 , the replacement | exchange operation | work of a belt can be simplified further.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view of an image forming apparatus.
FIG. 2 is a schematic side view of the belt device when viewed in the direction of arrow II in FIG. 1, with some elements omitted and a part simplified.
FIG. 3 is a front view of the belt device as viewed from the front side of the image forming apparatus.
FIG. 4 is a front view of the belt device with the second and third support members removed, as viewed from the front side of the image forming apparatus.
FIG. 5 is a front view of the belt device when the third support member is detached from the second support member.
[Explanation of symbols]
5 Waste toner tank 16 Roller 17 Roller 18 Roller 19 Roller 20 Roller 31 Cleaning device 40 First support member 41 Second support member 42 Third support member 45 Stay

Claims (5)

In a belt device having a belt wound around a plurality of rollers, a first support member that supports one end of all of the plurality of rollers and a second support that supports the other end of some of the rollers. a support member, and a third supporting member for supporting the other end of the other roller, the support members of said third have been detachably fixed to the second support member, said first The support member and the second support member are fixed to each other via a stay in a state where the position of the support member is adjusted by a jig, and the article can be stored in the inner space of the belt. The stay also serves as a guide for guiding the article when the article is taken out from the stay and when the article is put into the stay. Belt device. The belt device according to claim 1, wherein the third support member supports the other end of one roller . The belt, the image belt device according to claim 1 or 2 formed Ru from the image bearing belt that carries a. An image forming apparatus comprising the belt device according to claim 3 . A cleaning device that removes toner remaining on the image carrying belt after the toner image on the image carrying belt is transferred, and the article is a waste containing the toner removed from the image carrying belt by the cleaning device. the image forming apparatus according to claim 4 Ru toner tank der.

Images