JP3886882B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention electrophotographic copying machine, a printer, an image forming apparatus incorporating the Berutoyuni' bets that apply to facsimile.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, image forming apparatuses such as full-color copying machines and color printers pass through four image forming units (yellow, magenta, cyan, and black) that form images of each color in parallel, and through these four image forming units. It has a transfer belt for conveying paper. As shown in FIG. 10, the transfer belt 51 is stretched around a pair of rollers 53 and 55 that are spaced apart from each other below the process unit, and runs while being in contact with the photosensitive drums of the respective colors. . The transfer belt 51 and rollers 53 and 55 are unitized and incorporated as a belt unit 50 in an image forming apparatus such as a copying machine (see, for example, Patent Document 1).
[0003]
In such a belt unit, when the belt unit is removed from the main body and placed on a floor or a stand for maintenance, there is a risk that the surface may be rubbed and scratched if the belt surface directly contacts the floor surface. . In order to solve such a problem, measures are taken such as a method of providing a leg in which the side plate of the belt unit is greatly protruded from the belt exposed surface, or a vertical arrangement of the belt unit.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-040753
[Problems to be solved by the invention]
However, due to the recent downsizing of the device, the contact surface of the belt member with other units such as photoconductors and transfer rollers becomes wider, and it is not easy to provide a leg that protrudes greatly on the unit side plate, and the unit has an elongated shape This makes vertical installation difficult.
[0006]
An object of the present invention is to provide an image forming apparatus including a belt unit that can prevent the belt surface from being damaged when the belt unit is taken out of the casing and placed on the floor.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 is an image carrier that carries an electrostatic latent image, a developing device that visualizes the electrostatic latent image on the image carrier, and a visible image on the image carrier. An intermediate transfer body to which images are sequentially transferred, wherein the intermediate transfer body includes a roller and a belt stretched over the roller, and the image forming apparatus has a housing. The belt unit is a detachable belt unit, and the belt unit is supported by a rotatable frame to which a black transfer roller among the rollers is attached, and is pivotally supported by the belt unit, in an inner surface direction or an outer peripheral surface direction of the belt surface. A contact prevention member that rotates and prevents the belt outer peripheral surface from directly contacting the floor when the belt unit is removed from the housing, and the contact prevention member is disposed on the inner surface side of the belt surface. By rotating, front The frame is pressed against the image carrier, and a roller attached to the frame is pressed against the image carrier and rotated toward the outer peripheral surface of the belt surface, whereby the frame is pressed against the image carrier. The roller is released to separate the roller from the image carrier.
[0008]
According to the first aspect of the present invention, when maintaining the belt unit, the belt unit is taken out of the casing and placed on the floor with the surface on which the contact prevention member is provided facing down. When the belt unit is placed on the floor, the contact prevention member contacts the floor surface, so the belt does not directly contact the floor surface, and the belt surface can be prevented from being damaged, and image formation is easy to maintain. A device can be obtained. Further, when the belt unit is mounted on the casing, the frame is pressed by the contact preventing member, and the black transfer roller is pressed toward the electrostatic latent image carrier. On the other hand, when the contact preventing member is removed from the frame, the pressure contact of the frame is released, and the pressure on the image carrier by the black transfer roller is also released. As described above, the contact roller can be brought into and out of contact with the contact preventing member, so that no additional member is required to perform the contact and separation operation, and space saving and cost reduction can be achieved.
[0009]
The invention according to claim 2 is the invention according to claim 1, wherein when the belt unit is mounted in the housing, the contact prevention member is entirely on the inner surface side of the belt surface. When the belt unit is pulled out from the housing, the contact prevention member rotates in the direction of the outer peripheral surface of the belt surface, and the tip of the contact prevention member is connected to the outer surface of the belt surface. It protrudes to the side.
[0010]
The invention according to claim 2 has the same effect as that of the invention according to claim 1, and when the belt unit is in the housing, the contact preventing member is in the belt unit when viewed from the attaching / detaching direction of the unit. When the belt unit is taken out from the casing , the belt unit can be rotated in a projecting direction from the unit, so that a storage space in the casing can be reduced.
[0011]
The invention according to claim 3 is the invention according to claim 1 or 2, wherein the contact prevention member includes a spring, and the contact prevention is performed when the belt unit is mounted in the housing. The member abuts against the inner surface of the casing against the bias of the spring, and when the belt unit is pulled out from the casing, the contact prevention member rotates in accordance with the bias of the spring. It is characterized by that.
[0012]
The invention described in claim 3 has the same effect as that of the invention described in claim 1 or 2, and when the belt unit is pulled out from the housing, the contact preventing member rotates in accordance with the spring bias. Therefore, it is not necessary to manually rotate the contact prevention member, and the operability is excellent.
[0013]
The invention according to claim 4 is the invention according to claim 1 or 2, wherein the contact preventing member is provided on a side surface of the belt unit and also functions as a handle of the belt unit. To do.
[0014]
The invention according to claim 4 has the same effect as that of the invention according to claim 1 or 2, and the contact preventing member is provided on both sides of the belt unit and also serves as a handle. as it is pulled out can Succoth Te, drawer of the belt unit can be easily.
[0015]
The invention according to claim 5 is the invention according to claim 1 or 2, wherein the contact prevention member has a rotation shaft, and the length of the contact prevention member in the longitudinal direction is the rotation shaft. When the belt unit is rotated to the center and protrudes obliquely with respect to the outer circumferential surface of the belt unit in the longitudinal direction, the belt unit is long enough to support the belt unit in a vertically placed state.
[0016]
The invention according to claim 5 has the same effects as those of the invention according to claim 1 or 2, and when the belt unit is placed vertically, the contact preventing member is arranged in the longitudinal direction of the belt unit. Stability can be obtained with the belt unit and the contact prevention member simply by making it oblique, and the belt unit can be placed on the floor even in a small space.
[0017]
The invention according to claim 6 is the invention according to claim 1, wherein the belt unit has a substantially circular member, and the substantially circular member is provided on at least two belt exposed surfaces, and which are located out collision outside of and the belt unit beyond the belt exposed surface.
[0018]
In the invention according to the sixth aspect, the same effect as the invention according to the first aspect is obtained, and the substantially circular member is provided so as to protrude from at least two exposed surfaces of the belt unit. which of both sides of the unit in the bottom also rather good, a good convenience of.
[0023]
The invention according to claim 7 is the invention according to any one of claims 1 to 6 , wherein the belt unit is an intermediate transfer belt unit that contacts a plurality of electrostatic latent image carriers when mounted. To do.
[0024]
In the invention as set forth in claim 7, with the same effects as the invention described in any one of claims 1 to 6, by applying the above-mentioned belt unit to the intermediate transfer belt unit, and maintenance easy An image forming apparatus can be obtained.
[0027]
According to an eighth aspect of the present invention, in the invention according to any one of the first to sixth aspects, when the belt unit is attached to the casing of the image forming apparatus, the peripheral surface of the belt is the casing. It contacts with a plurality of rollers provided in the.
[0029]
The invention according to claim 8 has the same operational effects as the invention according to any one of claims 1 to 6 and is easy to maintain by applying the belt unit of the invention to each unit. A forming device can be obtained.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0031]
1 is a front view showing the belt unit of the first embodiment, FIG. 2 is a front view showing the belt unit of the second embodiment, FIG. 3 is a front view showing the belt unit of the third embodiment, and FIG. FIG. 5 is a front view showing a belt unit according to a fifth embodiment, FIG. 6 is a front view showing a belt unit according to a sixth embodiment, and FIG. 7 is a belt unit according to the seventh embodiment. FIG. 8 is a front view showing the belt unit of the eighth embodiment, and FIG. 9 is a cross-sectional view schematically showing the entire image forming apparatus of the present invention.
[0032]
The image forming apparatus 100 according to the present embodiment is a color copying machine, and includes a paper feeding unit 31 that stores transfer paper, and a plurality of electrostatic latent image carriers (photoconductors) 33 that perform image formation by exposure. The electrostatic latent image formed on the image forming unit 35 and the photoconductor 33 is visualized, and the toner image of the primary intermediate transfer body 37 and the primary intermediate transfer body 37 that sequentially transfer the visible image are collectively transferred. The image forming apparatus includes a secondary intermediate transfer member 39, a fixing device 41 that heats and pressurizes the transfer paper, and a paper discharge unit 43 that discharges the transferred transfer paper.
[0033]
When the image forming cycle is started, each photoconductor 33 is rotated in a predetermined direction by a drive motor (not shown), and the surface of the photoconductor 33 is uniformly charged by the charging device. An electrostatic latent image is formed on the photosensitive member 33 by exposure, and the electrostatic latent image on the photosensitive member 33 is developed as a toner image by the developer of the developing device. As the primary intermediate transfer member 37 rotates, yellow, magenta, cyan, and black toner images are sequentially stacked.
[0034]
When a desired color image is laminated on the primary intermediate transfer member 37, the color images are collectively transferred onto the secondary intermediate transfer member 39. When the color image is transferred from the secondary intermediate transfer member 39 to the transfer paper, the fixing is performed at the nip portion of the fixing device 41 and the paper is discharged from the paper discharge unit 43.
[0035]
Next, a primary intermediate transfer member (hereinafter referred to as a belt unit) 37 that is a characteristic part of the present invention will be described. First, as shown in FIG. 1, in the first embodiment, the belt unit 37 includes an intermediate transfer belt 5 stretched around a roller 3 and side plates 6 on both sides, and is detachable from the casing of the image forming apparatus 100. Is provided. In the present embodiment, the side plate 6 of the belt unit 37 is provided with contact preventing members 1 and 2 that prevent the intermediate transfer belt 5 from coming into direct contact with the floor surface when taken out from the housing. One contact prevention member 2 has a substantially semicircular shape protruding from the belt exposed surface of the belt unit 37, but the other contact prevention member 1 has a dotted line position in FIG. 1 when the belt unit 37 is attached to the housing. As shown in FIG. 1, the belt unit 37 is located in the belt unit 37 as viewed from the direction of attachment and detachment, and when the belt unit 37 is taken out of the housing, it rotates in a direction protruding from the belt unit 37 as shown by the solid line position in FIG. Is possible.
[0036]
Next, the operation of the present embodiment will be described based on the above configuration. When maintaining the belt unit 37, the belt unit 37 is taken out of the housing and placed on the floor with the surface on which the contact preventing member 1 is provided facing down. When the belt unit 37 is placed on the floor, the contact preventing member 1 is in contact with the floor surface, so that the intermediate transfer belt 5 does not directly contact the floor surface, and the surface of the intermediate transfer belt 5 is maintained when the belt unit 37 is maintained. Can be prevented from being damaged.
[0037]
Next, other embodiments will be described. In the description, parts having the same functions and effects as those described above are denoted by the same reference numerals, and detailed description thereof is omitted.
[0038]
The second embodiment is different from the first embodiment in that a coil spring spring (spring) 7 is provided on the contact preventing member 1a. The contact preventing member 1 a includes a rotation shaft 9 that is the center of rotation, and a coil spring spring 7 is wound around the rotation shaft 9. When the belt unit 37 is in the housing, the contact preventing member 1a is in the position indicated by the dotted line shown in FIG. 2 against the urging force of the coil spring 7 and is locked to the locking portion 11 in the housing. It is.
[0039]
When the belt unit 37 is pulled out from the housing, the contact preventing member 1a rotates in accordance with the bias of the coil spring 7 and protrudes from the unit 37 as shown by the solid line position in FIG. As described above, since the coil spring spring 7 is provided on the contact prevention member 1a, when the belt unit 37 is pulled out from the inside of the housing, the contact prevention member 1a is manually rotated. There is no need to rotate, and operability is excellent.
[0040]
The third embodiment is different from the first embodiment in that the contact preventing member 1b also serves as a handle. The handle is a substantially rectangular and hollow member, and one end thereof is rotatably fixed to the side plate 6 of the belt unit 37. When the belt unit 37 is in the housing, the contact preventing member 1b is in the unit. When the belt unit 37 is taken out of the housing and placed on the floor, the contact preventing member 1b is rotated to rotate the belt. Project from the unit 37. In the third embodiment, since the belt unit 37 serves as a handle, it can be easily pulled out.
[0041]
The fourth embodiment is different from the first embodiment in that the shaft of the contact prevention member 1c is provided slightly closer to the center and the contact prevention member 1c is longer. In the fourth embodiment, when the belt unit 37 is placed vertically, the belt unit 37 and the contact prevention member 1c are stable only by making the contact prevention member 1c oblique to the longitudinal direction of the belt unit 37. The belt unit 37 can be placed on the floor even in a small space.
[0042]
Next, the fifth embodiment is different from the first embodiment in that the contact preventing member 4 is also provided on the upper side of the belt unit 37. As shown in FIG. 5, the contact preventing member 2 a shown on the left side of the drawing has a substantially circular shape, and covers the upper and lower surfaces of the belt exposed surface at the end of the belt unit 37. Further, on the upper side of the belt unit 37, a contact preventing member 4 having a substantially semicircular shape is formed. Thus, since the contact prevention member 4 is provided both above and below the belt unit 37, when the belt unit 37 is pulled out from the housing and placed on the floor, the surface of the contact prevention member 1 is facing downward. It is not necessary to place it on the floor after confirming the above, and it is possible to prevent the belt 5 from being damaged by mistakenly placing the surface without the contact preventing member 1 on the floor.
[0043]
The sixth embodiment is different from the fifth embodiment in that at least one contact preventing member 1 is rotatable. In the sixth embodiment, when the contact preventing member 1 is in the housing, it does not protrude from the belt unit 37, so that space can be saved correspondingly.
[0044]
The seventh embodiment is characterized in that a roller shaft 13 such as a cleaning counter roller protrudes from the side plate 6 of the belt unit 37. In the seventh embodiment, since the roller shaft 13 protrudes from the side plate, the belt unit 37 is not placed on the floor with the side plate 6 of the belt unit 37 down, and the risk of the belt unit 37 falling down is prevented in advance. be able to.
[0045]
The eighth embodiment is characterized in that when the belt unit 37 is set in the housing, the contact preventing member 1d is interlocked with the contact / separation operation with respect to the photoreceptor 33. Each roller 3 moves a frame with a contact / separation cam to perform contact / separation operation with the photosensitive member 33. The row Align the contact and separation operations of the black transfer roller 3a only of the plurality of rollers to speed up printing, the black toner image on the transfer belt 5 is adapted to be transferred at the time of monochrome output.
[0046]
The black transfer roller 3a is attached to a monochrome frame (hereinafter referred to as a monochrome frame) 15, and the monochrome frame 15 can be rotated around a driven roller. The contact preventing member 1 d can be pressed against the monochrome frame 15. When the contact preventing member 1d rotates into the belt unit 37, the monochrome frame 15 is pressed toward the photosensitive member 33, and the black transfer roller 3a is also pressed against the photosensitive member 33. When the contact preventing member 1d is removed from the monochrome frame 15, the pressure contact by the contact preventing member 1d is released, so that the black transfer roller 3a is separated from the photosensitive member 33 and the belt unit 37 can be easily removed.
[0047]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. In the above-described embodiment, the belt unit 37 of the present invention is applied to the primary intermediate transfer member of the color copying machine, but may be applied to a secondary intermediate transfer member or a conveyance belt unit.
[0048]
The belt unit 37 is not limited to a copying machine, and may be a printer, a fax machine, or the like.
[0049]
【The invention's effect】
According to the first aspect of the present invention, when the belt unit is maintained, the belt unit is taken out of the housing and placed on the floor with the surface on which the contact prevention member is provided facing down. When the belt unit is placed on the floor, the contact prevention member contacts the floor surface, so the belt does not directly contact the floor surface, and the belt surface can be prevented from being damaged, and image formation is easy to maintain. A device can be obtained. In addition, since the black transfer roller can be brought into and out of contact with the contact preventing member, it is not necessary to provide a separate member in order to perform the contact and separation operation, and space saving and cost reduction can be achieved. Can do.
[0050]
The invention according to claim 2 has the same effect as that of the invention according to claim 1, and when the belt unit is in the housing, the contact prevention member is in the belt unit as seen from the attaching / detaching direction of the unit. When the belt unit is taken out from the casing, the belt unit can be rotated in a projecting direction from the unit, so that a storage space in the casing can be reduced.
[0051]
The invention according to claim 3 has the same effect as the invention according to claim 1 or 2, and when the belt unit is pulled out from the housing, the contact preventing member rotates in accordance with the bias of the spring. It is not necessary to manually rotate the contact prevention member, and the operability is excellent.
[0052]
The invention described in claim 4 has the same effect as that of the invention described in claim 1 or 2, and the contact preventing members are provided on both sides of the belt unit and also serve as handles. pull out can Succoth, drawer of the belt unit can be easily.
[0053]
The invention according to claim 5 has the same effect as that of the invention according to claim 1 or 2, and when the belt unit is placed vertically, the contact preventing member is inclined with respect to the longitudinal direction of the belt unit. By doing so, stability can be obtained by the belt unit and the contact preventing member, and the belt unit can be placed on the floor even in a small space.
[0054]
In the invention according to the sixth aspect, the same effect as the invention according to the first aspect is obtained, and the substantially circular member is provided so as to protrude from at least two exposed surfaces of the belt unit. which of the two sides also rather good in the bottom, a good convenience of.
[0057]
In the invention of claim 7, wherein, the same effects as in the invention described in any one of claims 1 to 6, by applying the above-mentioned belt unit to the intermediate transfer belt unit, maintenance easily the image forming apparatus Can be obtained.
[0059]
The invention according to claim 8 provides the same effect as the invention according to any one of claims 1 to 6 , and an image forming apparatus that is easy to maintain by applying the belt unit described above to each unit. Obtainable.
[Brief description of the drawings]
FIG. 1 is a front view showing a belt unit according to a first embodiment.
FIG. 2 is a front view showing a belt unit according to a second embodiment.
FIG. 3 is a front view showing a belt unit according to a third embodiment.
FIG. 4 is a perspective view showing a belt unit according to a fourth embodiment.
FIG. 5 is a front view showing a belt unit of a fifth embodiment.
FIG. 6 is a front view showing a belt unit according to a sixth embodiment.
FIG. 7 is a front view showing a belt unit according to a seventh embodiment.
FIG. 8 is a front view showing a belt unit according to an eighth embodiment.
FIG. 9 is a cross-sectional view schematically showing the entire image forming apparatus of the present invention.
FIG. 10 is a perspective view showing a conventional belt unit.
[Explanation of symbols]
1, 1a, 1b, 1c, 1d Contact prevention member 3 Transfer roller (roller)
5 Intermediate transfer belt (belt)
6 Side plate 7 Coil spring (spring)
9 Rotating shaft 11 Monochrome frame (contact part)
33 Photoconductor (electrostatic latent image carrier)
37 Belt unit 100 Image forming apparatus

Claims (8)

An image carrier that carries an electrostatic latent image, a developing device that visualizes the electrostatic latent image on the image carrier, an intermediate transfer member that sequentially transfers the visible image on the image carrier, In an image forming apparatus having
The intermediate transfer member is a belt unit that includes a roller and a belt stretched over the roller, and is detachable from the housing of the image forming apparatus.
The belt unit includes a rotatable frame to which a black transfer roller among the rollers is attached, and is pivotally supported by the belt unit. The belt unit rotates in an inner surface direction or an outer peripheral surface direction of the belt surface. A contact preventing member for preventing the outer peripheral surface of the belt from coming into direct contact with the floor surface when taken out from the housing;
The contact preventing member rotates to the inner surface side of the belt surface to press the frame against the image carrier, and presses a roller attached to the frame against the image carrier to An image forming apparatus, wherein the roller is moved away from the image carrier by releasing the pressure contact of the frame to the image carrier by rotating to the surface side. The image forming apparatus according to claim 1.
When the belt unit is mounted in the housing, the contact preventing member is entirely present on the inner surface side of the belt surface, and when the belt unit is pulled out from the housing, The image forming apparatus, wherein the contact prevention member rotates in the direction of the outer peripheral surface of the belt surface, and a tip portion of the contact prevention member protrudes to the outer surface side of the belt surface. The image forming apparatus according to claim 1, wherein
The contact prevention member includes a spring, and when the belt unit is mounted in the housing, the contact prevention member abuts against the inner surface of the housing against the bias of the spring, The image forming apparatus, wherein when the belt unit is pulled out from a housing, the contact prevention member rotates in accordance with the bias of the spring. The image forming apparatus according to claim 1, wherein
The image forming apparatus, wherein the contact preventing member is provided on a side surface of the belt unit and also functions as a handle of the belt unit. The image forming apparatus according to claim 1, wherein
The contact preventing member has a rotating shaft,
The length of the contact prevention member in the longitudinal direction can support the belt unit in a vertically placed state when the contact prevention member pivots about the pivot shaft and protrudes obliquely with respect to the longitudinal outer circumferential surface of the belt unit. An image forming apparatus characterized by having a long length. The image forming apparatus according to claim 1.
The belt unit has a substantially circular member,
The image forming apparatus, wherein the substantially circular member is provided on at least two belt exposed surfaces and protrudes beyond the belt exposed surface and outside the belt unit. The image forming apparatus according to any one of claims 1 to 6,
The image forming apparatus, wherein the belt unit is an intermediate transfer belt unit that comes into contact with a plurality of electrostatic latent image carriers when mounted. The image forming apparatus according to any one of claims 1 to 6,
The image forming apparatus, wherein when the belt unit is attached to a housing of the image forming apparatus, a peripheral surface of the belt is in contact with a plurality of rollers provided in the housing.

Images