JP3544808B2 - Image forming device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides an image forming method in which a toner image formed on an image carrier is transferred to a recording medium by a transfer device, and the recording medium is subjected to a charge removing operation by a charge removing device to separate the recording medium from the image carrier. It concerns the device.
[0002]
[Prior art]
In an image forming apparatus of the above-described type configured as a copier, a printer, a facsimile, or a composite machine thereof, for example, a recording medium made of transfer paper is conveyed to a transfer area between the image carrier and the transfer device. At this time, the toner image on the image carrier is transferred onto the recording medium by the operation of the transfer device, and the recording medium is separated from the image carrier by the static elimination action of the static eliminator.
[0003]
The transfer device includes, for example, a transfer roller, a transfer blade or a transfer brush that comes into contact with the image carrier, and a corona discharge device that is opposed to the image carrier in a non-contact state. When used for a long period of time, its performance deteriorates. If the deteriorated transfer device is continuously used, an abnormal image is generated. Therefore, it is necessary to clean and check the transfer device periodically or as necessary, or to replace the transfer device with a new one when the life of the transfer device has expired.
[0004]
On the other hand, if the static eliminator is used for a long period of time, its performance deteriorates, and if the deteriorated static eliminator is used as it is, an abnormal image also occurs. Therefore, like the transfer device, the static eliminator needs to be cleaned and inspected periodically or as needed, or when the life of the static eliminator expires, it is necessary to replace the static eliminator with a new one.
[0005]
Therefore, in a conventional image forming apparatus, the transfer device and the static eliminator are pre-assembled integrally so that both the transfer device and the static eliminator can be removed from the main body of the image forming device at the time of repair or replacement thereof. Make up. After the repair, the transfer device and the charge eliminator, or the new transfer device and the charge eliminator, are set together in the image forming apparatus main body.
[0006]
As described above, also in the conventional image forming apparatus, since the transfer device and the static eliminator are detachably attached to the image forming device main body, they are inspected or cleaned, or they have reached the end of their life. Sometimes it can be exchanged for a new one. However, the cleaning, inspection, and replacement cycles of the transfer device and the static eliminator may be different from each other, and the charge eliminator generally has a shorter life than the transfer device. In such a case, when the static eliminator reaches the end of its life at a certain point in time and needs to be replaced, the transfer device has not reached the end of its life and its replacement is unnecessary.
[0007]
In such a case, in the above-described conventional image forming apparatus, the transfer device and the static eliminator are integrally assembled, and these are configured to be detachably attached to the image forming apparatus main body together. It is not possible to remove only the static eliminator from the image forming apparatus main body and replace it.
[0008]
Also, when it is necessary to clean only the static elimination device, even the transfer device that does not need to be cleaned must be removed from the image forming apparatus main body, and unnecessary work is forced.
[0009]
On the other hand, there is also known an image forming apparatus configured such that a transfer device and a static eliminator can be completely separately set in an image forming apparatus main body, and these can be completely separated from the image forming apparatus main body. According to such an image forming apparatus, when the transfer device has not reached the end of its life and only the neutralization device has reached the end of its life, it is necessary to remove only the neutralization device from the image forming device and replace it with a new one. Can be. It is possible to perform operations such as replacement of only the static eliminator or transfer device, and cleaning and inspection thereof.
[0010]
However, according to this configuration, the transfer device and the static eliminator must always be separately attached to and detached from the main body of the image forming apparatus. However, it becomes complicated and the work efficiency decreases. For example, when both the transfer device and the static eliminator have reached the end of their service life, or when they need to be cleaned or inspected together, they must be separately removed from or attached to the image forming apparatus main body, which makes the work extremely difficult. It becomes troublesome.
[0011]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus of the type described at the beginning, in which the above-mentioned conventional disadvantages are eliminated by a simple configuration.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides, in an image forming apparatus of the type described at the beginning, a first holding member movably supported with respect to an image forming apparatus main body, wherein a holding body for holding a transfer device; A transfer device attached to the first holding member and a second holding member detachably connected to the first holding member, wherein the static eliminator is detachably mounted to the second holding member; Pressing means for contacting the static eliminator with the operation of the first holding member and pressing the static eliminator to a regular position with respect to the second holding member when the first holding member is not properly mounted on the second holding member. There is proposed an image forming apparatus characterized by having (1).
[0014]
In the image forming apparatus according to the first aspect, it is particularly advantageous that the transfer device is detachably attached to the second holding member (claim 2).
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
FIG. 1 is a schematic sectional view showing the inside of an image forming apparatus according to an embodiment of the present invention from the front side, and an image forming unit 2 is detachably mounted on the image forming apparatus main body 1. The image forming apparatus shown here is configured as a copying machine, and the copying machine may have functions such as a printer and a facsimile. The front side of the image forming apparatus or its main body 1 is usually the side where the operator operates the image forming apparatus, and the opposite side is the back side of the image forming apparatus or its main body 1. The front side may be referred to as the near side. The image forming unit 2 is attached to and detached from the image forming apparatus main body from the near side of the image forming apparatus main body 1.
[0017]
FIG. 2 is an enlarged sectional view when the image forming unit 2 and the transfer unit 3 are viewed from the front side. As shown in FIGS. 1 and 2, the image forming unit 2 has a unit case 4, and inside the case 4 is a drum-shaped photosensitive member 5 as an example of an image carrier and an example of a charging device. Each of the charging rollers 6 is rotatably mounted.
[0018]
During the image forming operation, the photoconductor 5 is rotated clockwise in FIG. 2 by a driving device (not shown), and at this time, the surface of the photoconductor is neutralized to the reference potential by the neutralizing light L1. The charging roller 6 is driven to rotate while being pressed against the surface of the photoreceptor 5, and uniformly charges the surface of the photoreceptor to a predetermined polarity. The surface of the photoconductor 5 charged in this way is irradiated with a light image from a document or a light-modulated laser L2, whereby a predetermined electrostatic latent image is formed on the photoconductor 5.
[0019]
On the other hand, a developing roller 8 of a developing device 7 is rotatably supported in the unit case 4 as shown in FIG. 2, and a developer D is stored in a developing case 9 formed by a part of the unit case 4. The developer D is carried and conveyed on a developing roller 8 which is driven to rotate counterclockwise. When the transported developer reaches between the photoconductor 5 and the developing roller 8, the toner in the developer is electrostatically transferred to the electrostatic latent image formed on the photoconductor 5, and the latent image is transferred to the toner. It is visualized as an image.
[0020]
The transfer unit 3 includes a transfer roller 11, which is one configuration example of a transfer device, a static eliminator 12, and a holder 13 that holds these in a manner described later. Extends. The static eliminator 12 shown as an example in FIG. 1 includes a static elimination needle 14 extending in parallel to the photoconductor 5 and a holder 15 for holding the same. During the image forming operation, the transfer unit 3 takes the posture shown in FIG. 2 with respect to the photoconductor 5, and at this time, the transfer roller 11 occupies the operating position pressed against the surface of the photoconductor 5, and is driven to rotate counterclockwise. Is done.
[0021]
On the other hand, a transfer sheet P, which is an example of a recording medium, is supplied from a selected one of the plurality of sheet feeders 16, 17, 18, and 19 shown in FIG. The sheet is conveyed to the transfer area 20 as indicated by an arrow A. Then, when the transfer paper P passes through the transfer area 20, the toner image formed on the surface of the photoconductor 5 is transferred onto the transfer paper P by the action of the transfer voltage applied to the transfer roller 11. A voltage having a polarity opposite to the polarity of the charged toner on the surface of the photoconductor 5 is applied to the transfer roller 11.
[0022]
On the other hand, the static eliminator is located downstream of the transfer roller 11 with respect to the transfer direction of the transfer paper P, and the discharge paper P is generated by the discharge needle 14 of the static eliminator 12 toward the surface of the photoreceptor 5. Is separated from the photoconductor 5. The transfer sheet P conveyed in the direction of arrow B leaving the photoconductor 5 passes through the fixing device 21. At this time, the toner image on the transfer sheet is fixed on the transfer sheet by the action of heat and pressure. Next, the transfer paper P is discharged outside the main body of the image forming apparatus as a copy paper on which a recording image formed of a toner image is formed, and is stacked on a discharge tray 22.
[0023]
The toner remaining on the photoconductor 5 after the transfer of the toner image is removed from the surface of the photoconductor by the cleaning member 24 of the cleaning device 23 and falls into the cleaning case 25 formed by a part of the unit case 4.
[0024]
As described above, in the illustrated image forming apparatus, the toner image formed on the photoreceptor 5 as an example of an image carrier is transferred by the transfer roller 11 as an example of a transfer device to a transfer paper as an example of a recording medium. The recording medium is transferred to the recording medium P, and the recording medium is subjected to a static elimination action by the static eliminator 12 to separate the recording medium from the image carrier composed of the photoreceptor 5 to obtain a recorded image.
[0025]
Here, the transfer paper P is transported to a transfer area 20 between the photoconductor 5 and the transfer roller 11 and is subsequently transported from this area 20 to the fixing device 21. During this transport, a jam, that is, a paper jam is caused. Transfer paper jammed in this way must be removed from the transport path. Such a transfer paper removing operation is a jam processing operation. To facilitate this operation, it is necessary to separate the transfer roller 11 from the photoreceptor 5 and secure a jam processing space therebetween. is there. At this time, if a large jam processing space can be ensured, the jam processing operation can be easily performed, which is advantageous.
[0026]
Therefore, in the image forming apparatus of the present embodiment, the transfer unit 3, particularly, the holder 13 is configured as described below.
[0027]
FIG. 5 is a perspective view of the transfer unit 3, and FIG. 6 is an exploded perspective view thereof. As shown in these drawings and FIG. 2, the holding body 13 holding the transfer roller 11 as an example of the transfer device has a first holding member 26 and a second holding member 27, and the first holding member 26 The first holding member 26 is movably supported with respect to the image forming apparatus main body 1. In this example, the base end of the first holding member 26 is pivotally attached to the image forming apparatus main body 1. That is, on the base end side of the first holding member 26, concentric support holes 28 and 29 are formed at the near side and the back side, and the image forming apparatus main body 1 is formed in each of the support holes 28 and 29. The support pins 32, 33 protruding from the front side plate 30 on the near side and the rear side plate 31 on the back side constituting the frame are relatively rotatably fitted to each other, and the first holding member 26 is supported by the support pins 32. , 33 are rotatably supported about the central axis.
[0028]
The pivotal portion of the first holding member 26 with respect to the image forming apparatus main body 1, that is, the pins 32 and 33, are located downstream of the transfer area 20 in the transport direction of the transfer paper P, and the central axes of the pins 32 and 33, that is, The center of rotation of the first holding member 26 extends substantially parallel to the central axis of the photoconductor 5. The first and second holding members 26 and 27 are made of, for example, a hard synthetic resin.
[0029]
On the other hand, the second holding member 27 is rotatably connected to the free end side of the first holding member 26 via connecting means. As shown in FIG. 6, the coupling means includes substantially arc-shaped receiving portions 34 and 35 integrally protruding from the front and rear portions of the first holding member 26 on the free end side, and the second holding member 26. It is composed of connecting pins 36 and 37 integrally projecting from the near side and the back side on the base end side of the holding member 27. The connecting pins 36 and 37 are rotatably fitted to the receiving portions 34 and 35, respectively. ing. The center of rotation of the second holding member 27 with respect to the first holding member 26, that is, the common center axis of the two connecting pins 36 and 37 is also parallel to the center axis of the photoconductor 5.
[0030]
As shown in FIGS. 2 and 6, the transfer roller 11 has a central shaft 38 made of a conductive material, for example, metal, and a cylindrical elastic body 39 fixed therearound. The side and rear portions are rotatably supported by bearings 40 and 41, respectively. The bearings 40 and 41 are movably held by bearing holding portions 42 and 43 formed integrally with the second holding member 27 in a direction approaching or separating from the photoconductor 5, respectively. Compression springs 44 and 45 are press-fitted between the two holding members 27, respectively.
[0031]
As shown in FIG. 6, a gear 46 is fitted on the front side of the transfer roller 11 such that the gear 46 cannot rotate relative to the center shaft 38. , 48 are fitted rotatably. As described above, the transfer device including the transfer roller 11 is attached to the second holding member 27 of the holding body 13.
[0032]
As shown in FIG. 6, the holder 15 of the static eliminator 12 is mounted on the static eliminator mounting portion 57 of the second holding member 27 as described later.
[0033]
As shown in FIGS. 2 and 7, a holder support member 49 is disposed below the holder 13, and the support member 49 includes a bearing 50 and a bearing 50, respectively. The support member 49 is rotatably supported by the front side plate 30 and the rear side plate 31 via the support member 51, and the support member 49 is shown in the upright position shown in FIG. It can pivot between the sideways position. A knob 52 is integrally attached to a portion on the near side of the holding body support member 49.
[0034]
At the normal time when the image forming operation is performed as described above, the transfer roller 11 occupies the operating position in which the transfer roller 11 opposes and contacts the surface of the photoconductor 5 as shown in FIG. 27 also occupies the first position shown in FIG. At this time, the holding member support member 49 is at the upright position shown in FIG. 2, and supports the holding member 13 from below to hold the transfer roller 11 at the operating position. That is, as shown in FIG. 2, the base end of the leaf spring 53 is fixed to the near side and the back side of the first holding member 26, and the tip end 54 of the holding body support member 49 is fixed to the free end side. Press-contact to support the first holding member 26.
[0035]
At this time, as shown in FIG. 2, the opposing surfaces 55 and 56 (FIG. 6) of the first holding member 26 and the second holding member 27 abut. Thereby, the second holding member 27 is prevented from rotating around the connecting pins 36 and 37 in the clockwise direction in FIG. 2 (in a direction away from the photoconductor 5) with respect to the first holding member 26. .
[0036]
As described above, the opposing surfaces 55 and 56 of the first and second holding members 26 and 27 are disposed on the first holding member 27 while the transfer device including the transfer roller 11 occupies the operating position. It constitutes an example of a rotation restricting means for prohibiting the member 26 from rotating in a direction away from the image carrier composed of the photoconductor 5. By providing such a restricting means, both holding members 26 and 27 are reliably supported at the first position by a simple support structure in which the holding member supporting member 49 supports only the first holding member 26 from below, and the transfer is performed. The roller 11 can be reliably held at the operating position.
[0037]
When the transfer roller 11 occupies the operating position as described above, the front and rear abutment rollers 47 and 48 fitted to the central shaft 38 of the transfer roller 11 are exposed to the photosensitive member mounted on the unit case 4 of the image forming unit 2. The position of the transfer roller 11 with respect to the photoconductor 5 is determined by hitting each end of the body 5 in the axial direction. At this time, the elastic body 39 of the transfer roller 11 is pressed against the surface of the photoreceptor 5, and the compression springs 44 and 45, which are compressed and deformed, press the transfer roller 11 together with the bearings 40 and 41 against the photoreceptor 5, and the elastic body 39 is pressed against the surface of the photoreceptor and elastically deforms.
[0038]
Further, as shown in FIG. 8, the gear 46 fitted to the central shaft 38 of the transfer roller 11 meshes with the gear 58 provided at the end of the photoconductor 5, and during the image forming operation, as described above, the photoconductor 5 Is rotated, the rotation is transmitted to the transfer roller 11 via the gears 58 and 46, and the transfer roller 11 is driven to rotate.
[0039]
As shown in FIG. 6, an electrode 59 is fixed to the second holding member 27, and when the second holding member 27 occupies the first position, the electrode 59 is not shown on the image forming apparatus main body side. Touch the electrodes. The electrode 59 contacts the above-mentioned compression spring 45 on the back side, and the bearing 41 in contact with the spring 45 and the central shaft 38 of the transfer roller 11 is made of a conductive material. Thus, during the image forming operation, a predetermined voltage is applied to the transfer roller 11 via the electrode 59, the spring 45, and the bearing 41.
[0040]
The static elimination needles 14 of the static eliminator 12 have a large number of sharp needle-like projections arranged in the longitudinal direction and protruding toward the photoreceptor 5, and when the holder 15 is mounted on the mounting portion 57, FIG. As shown in FIG. 7, the static elimination needle portion exposed from the holder 15 contacts the electrode 60 fixed to the second holding member 27. When the second holding member 27 occupies the first position, the electrode 60 comes into contact with an electrode (not shown) provided on the image forming apparatus main body side, whereby a predetermined voltage is applied to the static elimination needle 14. Is done.
[0041]
As described above, when the transfer sheet P is jammed in the transfer area 20 or in the area before and after the transfer area P, the transfer roller 11 is largely separated from the surface of the photoconductor 5 as shown in FIG. Move to the evacuation position.
[0042]
When a jam occurs, the image forming operation is stopped. In this state, an operator opens a front door (not shown) of the image forming apparatus main body 1 and exposes the holding body support member 49 shown in FIG. Next, the user grips the knob 52 and rotates the holder support member 49 in the counterclockwise direction (the direction of arrow C) in FIG. 2 around the base end side thereof, while tilting the holder support member 49 as shown in FIG. It is brought to the lying position shown in FIG. As a result, the first holding member 26 rotates around the support pins 32 and 33 by its own weight, and accordingly, the second holding member 27 also operates, and the transfer roller 11 attached to the first holding member 26 moves the surface of the photoconductor 5. And occupies the retracted position shown in FIG.
[0043]
In this way, the first and second holding members 26 and 27 occupy the second position shown in FIG. 4, but at this time, the second holding member 27 is rotatable with respect to the first holding member 26. Because they are pivotally mounted, when they occupy the second position, the second holding member 27 bends relative to the first holding member 26 as shown in FIG. For this reason, even when the internal space of the image forming apparatus main body is not particularly large, when the transfer roller 11 occupies the retracted position, a large jam processing space S can be formed below the photoconductor 5. Therefore, the operator can easily put his hand in this space to remove the jammed transfer paper, and also can prevent the hand and clothes from touching the transfer roller 11 and the photoreceptor 5 and stain the hands and clothes with toner. In addition, it is possible to prevent foreign matters from adhering to the photoconductor 5.
[0044]
After the jam has been cleared, the operator grasps the knob 52 and rotates the holder supporting member 49 clockwise in FIG. 4, whereby the first and second holding members 26 and 27 are shown in FIG. Then, the transfer roller 11 may be raised to the first position to bring the transfer roller 11 to the operation position facing the photoconductor 5. Thus, the image forming operation can be restarted.
[0045]
As described above, in the image forming apparatus of the present embodiment, when the transfer device including the transfer roller 11 is in the operating position (FIG. 2) facing the surface of the image carrier including the photosensitive member 5 and the operating position (FIG. 2). The holding member 13 holding the transfer roller 11 has a base end side of the image forming apparatus main body 1 so that the holding member 13 can move between the retracted position (FIG. 4) far away from the surface of the photoconductor 5. A first holding member 26 pivotally attached to the first holding member 26, and a second holding member 27 pivotally attached to the free end of the first holding member 26. Thus, when the transfer roller 11 is brought to the retracted position, a large jam processing space S can be secured between the photoconductor 5 and the transfer roller 11.
[0046]
The holding member support member 49 supports the holding member 13 to hold the transfer device including the transfer roller 11 at the operating position (FIG. 2). When the transfer roller 11 is brought to the retracted position (FIG. 4), the holding member 49 is held. Since the retracted position is at a position where the rotation of the body 13 is allowed, that is, the retracted position shown in FIG. it can.
[0047]
Further, since the transfer device including the transfer roller 11 is attached to the second holding member 27 located on the free end side of the holding member 13, the first and second holding members 26 and 27 are not shown in FIG. When the transfer roller 11 is rotated to the position 2, the transfer roller 11 is largely separated from the photosensitive member 5, and a large jam clearance S can be reliably formed between the two.
[0048]
As shown in FIGS. 2 and 4, a base plate 61 fixed to the front and rear side plates 30 and 31 (FIG. 7) of the image forming apparatus main body is located below the photoreceptor 1, and a transfer roller 11 is provided. 4 occupies the retracted position as shown in FIG. 4, the second holding member 27 is supported by the base plate 61 of the image forming apparatus main body located below the photoconductor 5. In the example of FIG. 4, the holding body support member 49 occupying the sideways position is actually supported by the base plate 61, and the second holding member 27 is placed thereon, and the second holding member 27 is held by the holding body support member Although the second holding member 27 is supported by the base plate 61 directly via the base plate 61, the second holding member 27 may be directly supported by the base plate 61.
[0049]
In any case, since the second holding member 27 is supported by the base plate 61, the first holding member 26 and the second holding member 27 are moved in the direction in which the angle θ between the surfaces facing the photoconductor 5 decreases. The second holding member 27 rotates in a state where the second holding member 27 is reliably bent with respect to the first holding member 26. When the transfer roller 11 is brought to the retracted position, the second holding member 27 can be positively bent with respect to the first holding member 26. Accordingly, even when the image forming apparatus is small and the distance between the photoconductor 5 and the base plate 61 needs to be relatively narrow, a large jam processing space S is provided between the transfer roller 11 and the photoconductor 5. Can be secured.
[0050]
Moreover, when the transfer roller 11 occupies the retracted position as shown in FIG. 4, the second holding member 27 takes a posture substantially parallel to the base plate 61, that is, a substantially horizontal posture in the example of FIG. The relative position between the second holding member 27 and the base plate 61 is set. For this reason, the second holding member 27 is bent with respect to the first holding member 26 so that both of them are substantially L-shaped, and a maximum jam occurs between the transfer roller 11 and the photoconductor 5 occupying the retracted position. The processing space S can be secured.
[0051]
As shown by the broken line in FIG. 4, if the holding body 130 supporting the transfer roller 110 is not divided into two and is constituted by one piece, it is retracted from the photoconductor 5 as shown in FIG. Even if it is rotated to the second position, a large jam clearance space cannot be secured between the transfer roller 110 and the photoconductor 5, so that it is difficult to remove the jammed transfer paper, and the operator transfers the hand or clothes. There is a risk of touching the roller 110 and the photoconductor 5. On the other hand, in the image forming apparatus of this example, a large jam processing space S can be secured as described above.
[0052]
As the transfer device, in addition to using the transfer roller 11 as in the image forming apparatus of the present embodiment, a transfer brush or a transfer blade that comes into contact with the transfer paper in contact with the photoconductor can also be used. As in the case of the roller 11, a predetermined voltage is applied to transfer the toner image on the photoconductor to transfer paper. Further, as a transfer device, a corona discharger that performs corona discharge toward the photoconductor 5 and thereby separates the transfer paper P adhered to the photoconductor 5 may be used. When the corona discharger is in the operating position, it faces the surface of the photoconductor 5 in a non-contact state.
[0053]
On the other hand, the transfer device including the transfer roller 11 as in the present embodiment, when performing the transfer operation of the toner image, contacts the surface of the photoconductor 5 via the transfer paper P and rotates as shown in FIG. I do. That is, the transfer roller 5 is a contact-type transfer device that comes into contact with the surface of the photoconductor 5 via the transfer paper P or directly, but foreign matter such as oil adheres to the surface of such a transfer device for any reason. In this case, this shifts toward the photoconductor 5, thereby deteriorating the image quality of the toner image formed on the photoconductor. That is, when the transfer roller 11 is used, it is important to prevent foreign matter such as oil from adhering to the transfer roller 11 as much as possible. The same applies to a case where a transfer operation of a toner image is performed as a transfer device, and a case where a contact type transfer device such as a transfer brush or a transfer blade that comes into contact with an image carrier via a recording medium is used.
[0054]
However, in the image forming apparatus of the present embodiment, when the transfer roller 11 is brought to the retracted position as described above, a large jam processing space can be secured between the transfer roller 11 and the photoconductor 5, so that the operator can transfer the transfer roller 11 can be effectively prevented, oil and the like can be prevented from adhering to the transfer roller 11, and consequently, foreign substances can be prevented from adhering to the photoreceptor, and the image quality of the toner image can be prevented from deteriorating. This is the same when a contact type transfer device such as a transfer brush or a transfer blade is used. As described above, the configuration of the holding body 13 having the first and second holding members 26 and 27 can be particularly advantageously adopted when the transfer device uses a contact transfer device including, for example, a transfer roller. It is.
[0055]
FIG. 7 shows a state in which the image forming unit 2 shown in FIG. 2 is pulled out from the image forming apparatus main body 1 to the front side thereof and removed, and the first holding member 26 occupying the second position and the second holding member FIG. 7 is a perspective view showing a state where the image forming apparatus 27 is removed. As shown in this figure, the front side plate 30 on the front side of the image forming apparatus main body 1 is composed of, for example, a composite for protecting workers and improving aesthetic appearance. It is covered by an inner cover 62 made of resin. That is, the inner cover 62 covers a lower portion of the front plate 30 that defines the opening 63 formed in the front plate 30 of the image forming apparatus main body.
[0056]
In FIG. 4, the upper portion 62a of the inner cover 62 is simplified by a two-dot chain line. As can be seen from FIG. 4, when the transfer device including the transfer roller 11 occupies the retracted position, the transfer roller 11 The relative position between the second holding member 27 and the inner cover 62 is set such that the upper portion 11a is located at substantially the same height level as the upper portion 62a of the inner cover 62. Here, the substantially same height level means that the upper portion 11a of the transfer roller 11 is located within a range of 5 mm at the maximum in the vertical direction with respect to the upper portion 62a of the inner cover 62. The upper portion 11a of the transfer roller 11 is positioned within a range of ± 5 mm in the vertical direction with respect to the upper portion 62a of the inner cover 62.
[0057]
If the upper portion 11a of the transfer roller 11 occupying the retracted position is positioned as described above with respect to the upper portion 62a of the inner cover 62, the transfer roller 11 does not protrude significantly above the inner cover 62. This allows the transfer roller 11 to be hidden behind the inner cover 62. For this reason, when the operator puts his hand in the jam processing space S through the opening 63 on the front side of the image forming apparatus main body, it is possible to more reliably prevent the hand and clothes from touching the surface of the transfer roller 11. Accordingly, it is possible to prevent the worker from soiling his hands and clothes with the toner adhered to the transfer roller 11 and conversely prevent the surface of the transfer roller 11 from adhering oil or dust attached to the operator's hand.
[0058]
As shown in FIGS. 2 to 4, the base plate 61 of the image forming apparatus main body 1 is provided with a protrusion 64 that rises upward (see also FIG. 7). The projection 64 can be formed by cutting and raising the base plate 61 itself, or by fixing a plate-like tongue piece or the like to the base plate 61. By providing the projection 64, when the first and second holding members 26 and 27 are rotated from the first position shown in FIG. 2 to the second position shown in FIG. , 27 can be smoothly and reliably bent as shown in FIG.
[0059]
FIG. 9 shows a state in the middle of moving the transfer roller 11 from the operating position to the retracted position in the image forming apparatus having no projection on the base plate 61. As shown in this drawing, when the transfer roller 11 moves to a position near the retreat position, the tip of the second holding member 27 contacts the upper surface of the base plate 61 with a large area. At this time, the second holding member 27 attempts to rotate counterclockwise in FIG. 9 around the connecting pins 36 and 37 with respect to the first holding member 26 due to the reaction force received from the base plate 61. Since the distal end of the second holding member 27 has a large area in contact with the upper surface of the base plate 61, the second holding member 27 receives a large frictional force from the base plate 61. Therefore, the second holding member 27 may stop at the position shown in FIG. 9 without rotating with respect to the first holding member 26. In this case, it is necessary for the operator to press down the first and second holding members 26 and 27 from above and rotate them to the second position shown in FIG. 4, which makes the operation somewhat troublesome. Become.
[0060]
On the other hand, when the projection 64 is provided on the base plate 61 as shown in FIGS. 2 to 4, when the transfer roller 11 moves from the operating position to a position near the retreat position as shown in FIG. First, a rib 65 made of a thin plate provided on the bottom of the second holding member 27, in this example, abuts on the tip of the projection 64. At this time, the contact area between the two becomes very small, so that the frictional force acting on the second holding member 27 also becomes small. The frictional force acting on the second holding member 27 from the image forming apparatus main body side is reduced. Therefore, the second holding member 27 is effectively bent with respect to the first holding member 26 by the reaction force received from the projection 64. That is, the second holding member 27 rotates with respect to the first holding member 26 in a direction in which the angle θ formed between the surfaces of the first holding member 26 and the second holding member 27 facing the photoconductor 5 decreases. Therefore, the holding members 26 and 27 can be quickly moved to the second position shown in FIG. 4 without the operator manually pressing them.
[0061]
As described above, in the image forming apparatus of the present embodiment, when the transfer device including the transfer roller 11 moves from the operating position to a position near the retreat position, the photosensitive members of the first holding member 26 and the second holding member 27 In order to facilitate the rotation of the second holding member 27 with respect to the first holding member 26 in a direction in which the angle θ between the surfaces facing the second holding member 27 decreases, the second holding member 27 is moved from the image forming apparatus main body side. Is provided, and in the illustrated example, the projection 64 provided on the base plate 61 constitutes the frictional force reducing means.
[0062]
A roller (not shown) is rotatably provided at the distal end of the second holding member 27. When the transfer roller 11 moves to a position near the retreat position as shown in FIG. The second holding member 27 may be configured to reduce the frictional force received from the base plate 61 by rolling. In this case, the roller constitutes a frictional force reducing unit.
[0063]
By the way, when the first and second holding members 26 and 27 occupy the first position and therefore the transfer roller 11 occupies the operating position, as described above with reference to FIG. The mounted gear 46 meshes with a gear 58 provided integrally with the photoconductor 5, and the rotation of the photoconductor 5 is transmitted to the transfer roller 11. On the other hand, the first holding member 26 is pivotally connected to the image forming apparatus main body so as to be rotatable, and the second holding member 27 and the first holding member 26 are rotatably connected to each other. The holding member 27 is likely to rattle in the front-rear direction of the image forming apparatus main body, that is, in the axial direction of the transfer roller 11. Therefore, when the photoconductor 5 rotates, the meshing of the gears 46 and 58 becomes unstable, and the axial direction of the second holding member 27 and the transfer roller 11 is backlashed with respect to the photoconductor 1, thereby causing the photoconductor 1 to rotate. A so-called transfer omission phenomenon in which a part of the toner image on the body 5 is not transferred to the transfer paper may occur, and the image quality of the toner image on the transfer paper may be deteriorated.
[0064]
Therefore, in the image forming apparatus of the present embodiment, as shown in FIG. 8, a positioning hole 66 is formed in the second holding member 27, and a positioning pin 67 is protruded from the unit case 4 of the image forming unit 2 to transfer the image. When the roller 11 is brought to the operating position and the first and second holding members 26 and 27 are held at the first position, the positioning holes 66 and the positioning pins 67 are fitted with each other, thereby transferring the second holding member 27. Together with the roller 11, it prevents backlash in the axial direction. As a result, the occurrence of transfer omission can be prevented, and the image quality of the toner image transferred to the transfer paper can be improved.
[0065]
As described above, the image forming apparatus of the present embodiment has the means for positioning the second holding member 27 with respect to the main body of the image forming apparatus when the transfer device including the transfer roller 11 occupies the operating position. In the example, the positioning hole 66 and the positioning pin 67 constitute the positioning means. In this example, a positioning hole 66 is provided in the second holding member 27, and a positioning pin 67 fitted to the positioning hole 66 is provided in the image forming unit 2, and the second holding member 27 is positioned with respect to the image forming unit 2. Although the second holding member 27 is positioned with respect to the image forming apparatus main body, the second holding member 27 may be directly positioned with respect to the image forming apparatus main body.
[0066]
By the way, when the image forming operation described above with reference to FIG. 2 is performed, the first and second holding members 26 and 27 occupy the first position shown in FIG. The upper surface of the holding member 27 guides the transfer paper P conveyed to the transfer area 20 between the transfer roller 11 and the photoconductor 5. That is, the second holding member 27 forms the first guide surface 68 for guiding the transfer paper P conveyed to the transfer area 20 between the transfer device including the transfer roller 11 and the image carrier including the photoconductor 5. -ing
[0067]
Similarly, the upper surface of the first holding member 26 occupying the first position shown in FIG. 2 serves to guide the transfer paper P passing through the transfer area 20. That is, the first holding member 26 forms the second guide surface 69 for guiding the transfer paper P that has exited the transfer area 20 between the transfer device including the transfer roller 11 and the image carrier including the photoconductor 5. It is doing.
[0068]
As described above, since the first and second holding members 26 and 27 that constitute the holding body 13 that supports the transfer roller 11 also serve as guide members for guiding the transfer paper P, the number of parts of the image forming apparatus is reduced. Thus, the structure can be simplified and the cost can be reduced.
[0069]
In the present embodiment, the transfer device includes the transfer roller 11, and the upper surface of the first holding member 26 constitutes the second guide surface 69. At this time, as shown in FIG. In the transfer area 20 where the photoconductor 5 is in contact, a common tangent line T that is in contact therewith intersects the second guide surface 69 of the first holding member 26. The second guide surface portion 69a on the upstream side of the intersection Q in the transfer paper transport direction is located below the tangent line T and the transfer area 20 and the second guide surface portion 69a on the downstream side of the intersection Q in the transfer paper transport direction. The second guide surface portion 69b is located above the tangent line T.
[0070]
According to the above configuration, the leading end of the transfer paper P that has exited the transfer area 20 hits the second guide surface 69 at the intersection Q or a portion very close to the intersection Q, thereby restricting the transfer direction of the transfer paper P, Subsequently, the transfer paper moves along the second guide surface portion 69b downstream of the intersection point Q so as to be in close contact with the second guide surface portion 69b. In this way, the transfer paper that has exited the transfer area 20 can be smoothly guided to the second guide surface 69, and the guide surface 69 can be moved smoothly, so that the occurrence of jam of the transfer paper P can be suppressed.
[0071]
Here, as described above with reference to FIG. 2, the image forming apparatus of the present embodiment transfers the toner image formed on the image carrier configured as the photoconductor 5 as an example of a transfer device. The transfer paper P is transferred to a recording medium made of the transfer paper P by the roller 11, and the transfer paper P is subjected to a charge removing operation by the charge removing device 12 to separate the transfer paper P from the photoconductor 5. The performance of the static elimination needle 14 and the transfer device that are components of the static eliminator 12 deteriorates when they are used for a long period of time, and an abnormal image occurs when these are used as they are. Therefore, the transfer device and the static eliminator need to be cleaned or inspected regularly or as needed, or replaced with a new one.
[0072]
In order to satisfy such demands, as described above, in the conventional image forming apparatus, the transfer device and the static eliminator are integrally assembled, and this can be freely attached to and detached from the image forming apparatus main body. Was configured. However, according to this configuration, it is not possible to cope with the difference in the cleaning, inspection, or replacement cycle of the transfer device and the charge removing device. That is, the cycle of cleaning, checking, and replacing the charge removing needle 14 of the charge removing device 12 and the transfer roller 11 is generally different, and the charge removing needle 14 usually has a shorter cycle. When the exchange cycle of the transfer roller 11 is, for example, 100,000 copies, the exchange cycle of the static eliminator 12 including the static elimination needle 14 is, for example, 50,000. Therefore, in such a case, it is necessary to replace only the static eliminator 12 at the end of copying 50,000 sheets. However, as in the conventional image forming apparatus, the transfer device and the static eliminator are connected to the image forming apparatus main body. If it is configured to be integrally detachable, it is not possible to remove only the static eliminator from the image forming apparatus main body and replace it. Further, if toner or paper dust adheres to the tip of the needle-like projection of the charge removing needle 14, the charge removing function is significantly reduced. In this case, it is necessary to take out only the charge removing device 12 and clean the charge removing needle 14. However, such an operation cannot be performed by the conventional image forming apparatus.
[0073]
Further, as described above, an image forming apparatus in which the transfer device and the charge removing device can be attached to and detached from the image forming device main body completely separately is also known. According to this configuration, only the charge removing device is detached from the image forming device main body. It is possible. However, in this configuration, since the static eliminator and the transfer device cannot be integrally attached to and detached from the main body of the image forming apparatus, when the transfer device and the static eliminator need to be replaced at the same time, the operation becomes complicated. Explaining in the above example, when the copying of 100,000 sheets is completed, both the static eliminator and the transfer device reach the end of their life, so they need to be replaced together. The work has to be very troublesome, since it has to be done separately.
[0074]
As described above, in order to replace the transfer roller 11 and the charge removing device 12 at the same time, there are cases where they are removed together and cases where only the charge removing device 12 is removed. In the conventional image forming apparatus, both requirements are satisfied. I couldn't do that.
[0075]
Therefore, in the image forming apparatus of the present embodiment, the holding member 13 that holds the transfer device including the transfer roller 11 includes the first holding member 26 movably supported with respect to the image forming apparatus main body 1, and the transfer roller 11. And a second holding member 27 detachably connected to the first holding member 26, and a static eliminator mounting portion 57 of the second holding member 27 is attached to the transfer device. 12 is detachably mounted.
[0076]
According to the above configuration, when both the transfer roller 11 and the charge removing device 12 are exchanged, simply remove the second holding member 27 from the first holding member 26, and the transfer roller 11 and the charge removing device 12 are both replaced with the image forming apparatus main body 1. The transfer roller 11 and the static eliminator 12 are both attached to the image forming apparatus main body 1 by simply removing the transfer roller 11 and the second retaining member 27 with the new transfer roller 11 and the static eliminator attached to the first holding member 26. The transfer device 11 and the static eliminator can be attached and detached efficiently and easily.
[0077]
When only the static eliminator 12 is to be removed, it can be removed from the second holding member 27 and a new static eliminator 12 can be set on the second holding member 27. Only the charge removing device 12 can be attached and detached without attaching and detaching the transfer roller 11.
[0078]
Further, as described later, in the image forming apparatus of the present embodiment, a transfer device including the transfer roller 11 is detachably attached to the second holding member 27, whereby only the transfer roller is attached to the second holding member 27. It can also be attached and detached. With the static eliminator 12 attached to the second holding member 27, only the transfer roller 11 can be detached from the second holding member 27, and only the transfer roller can be replaced.
[0079]
Next, a specific configuration for detachably connecting the second holding member 27 to the first holding member 26 and a specific configuration for enabling the charge removing device 12 to be independently detachable from the second holding member 27. , As well as configurations related thereto will be clarified sequentially.
[0080]
The connection method of the second holding member 27 to the first holding member 26 can adopt various forms. For example, the second holding member 27 can be slid with respect to the first holding member 26 in the front-rear direction of the image forming apparatus main body 1. 5, the second holding member 27 is pulled toward the near side of the image forming apparatus main body as indicated by an arrow R in FIG. 5 so that the second holding member 27 can be detached from the first holding member 26. The two holding members 26 and 27 may be detachably connected by a connecting means such as a magnet (not shown) so that the second holding member 27 can be detached from the first holding member 26.
[0081]
However, the use of the connecting means composed of a magnet increases the cost due to the provision of the magnet, and also complicates the operation of attaching and detaching the second holding member 27 to and from the first holding member 26. When the second holding member 27 is slidably attached to the first holding member 26, when the second holding member 27 is pulled out to the near side, it interferes with the front side plate 30 (FIG. 7) of the image forming apparatus main body. The operation may be difficult.
[0082]
Therefore, in the present embodiment, attention is paid to the fact that the first holding member 26 and the second holding member 27 constituting the holding body 13 are pivotally connected to each other, and a connecting means for connecting these members is used. The second holding member 27 is configured to be detachable from the first holding member 26.
[0083]
That is, as shown in FIGS. 2 to 4, the first and second holding members 26 and 27 are in the first position when the transfer device including the transfer roller 11 occupies the operating position, and when the transfer roller 11 is retracted. The base end of the first holding member 26 is pivotally attached to the image forming apparatus main body 1 so as to be able to occupy the second position when occupied, and the second holding member 26 is attached to the free end thereof. The second holding member 27 is pivotally attached to the holding member 27 and the first and second holding members 26 and 27 are farther apart from the image carrier composed of the photoconductor 5 than when the first and second holding members 26 and 27 occupy the first position. When the first holding position is occupied, the angle θ between the surfaces of the holding members 26 and 27 facing the photoconductor 5 is smaller than when the first holding position is occupied. By rotating with respect to the first holding member 26, a large jam processing space S can be secured. However, in this example, this configuration is further developed, and the connecting means for detachably connecting the second holding member 27 to the first holding member 26 includes first and second holding members 26 and 27 serving as second connecting members. The first and second holding members can be attached and detached only when the angle between the two surfaces is smaller than the angle θ between the two surfaces when the position is occupied. .
[0084]
More specifically, as described above with reference to FIG. 6, the connecting means for connecting the first holding member 26 and the second holding member 27 is formed by an arc-shaped member attached to the first holding member 26. The receiving pins 34 and 35 and the connecting pins 36 and 37 integrally projecting from the second holding member 27 have the connecting pins 36 and 37, respectively. ), It is formed in an elongated oval shape having a width d. When the first and second holding members 26 and 27 are located between the first position shown in FIG. 2 and the second position shown in FIG. 4, as shown in FIG. The connecting pins 36 and 37 have their longitudinal ends 70 slidably fitted to the inner surfaces of the arc-shaped receiving portions 34 and 35, respectively. For this reason, although the connecting pins 36 and 37 are rotatable with respect to the receiving portions 34 and 35, they are not separated from each other, and thus the second holding member 27 is free without coming off with respect to the first holding member 26. Can be rotated.
[0085]
Here, after bringing the first and second holding members 26 and 27 to the second position shown in FIG. 4, the second holding member 27 is moved to the first holding member 26 while the first holding member 26 is stopped. Is rotated counterclockwise in FIG. When the first and second holding members 26 and 27 occupy the second position, the second holding member 27 is rotated so that the angle between the two surfaces becomes smaller than the angle θ between the two surfaces. To make it happen. Then, when the second holding member 27 rotates to the position shown in FIG. 11, the width d of both connecting pins 36 and 37 and the upper portions of the receiving portions 34 and 35 as shown in FIG. The opening matches.
[0086]
Therefore, if the second holding member 27 is lifted upward as shown by an arrow E in FIG. 11, the holding member 27 can be removed from the first holding member 26. In this way, the second holding member 27 removed from the first holding member 26 is taken out to the near side through the opening 63 of the image forming apparatus main body front side plate 30 shown in FIG. You can leave. By performing the reverse operation, the second holding member 27 can be assembled to the first holding member 26.
[0087]
As described above, the pivoting device composed of the connecting pins 36 and 37 and the receiving portions 34 and 35 makes it possible to determine the angle θ between the surfaces when the first and second holding members 26 and 27 occupy the second position. Also, the attachment and detachment of the two holding members 26 and 27 can be performed only when the angle between the two surfaces is further reduced. Since the second holding member 27 cannot come to the position shown in FIG. 11 during a normal image forming operation or a jam processing, the second holding member 27 is accidentally removed from the first holding member 26. There is no fear.
[0088]
According to the above configuration, since the second holding member 27 is not slid to the front side of the image forming apparatus main body and is not detached from the first holding member 26, the front holding plate 30 of the image forming apparatus main body 1 does not have any configuration. The second holding member 27 can be removed from the first holding member 26 or can be assembled without being disturbed. In addition, since the first and second holding members 26 and 27 are pivotally connected to each other using a pivoting device so as to detachably couple the first and second holding members 26 and 27, other members such as magnets are used. , It is possible to achieve a simplification of the structure and a reduction in cost, and it is possible to easily perform the attaching and detaching operation.
[0089]
Further, since the second holding member 27 is brought to the second position largely separated from the photoconductor 5 and can be attached to and detached from the first holding member 26, the attaching / detaching operation can be performed easily.
[0090]
After the second holding member 27 is detached from the image forming apparatus main body 1 as described above, the transfer roller 11 is lifted up with respect to the bearings 40 and 41 shown in FIGS. Since the pair of claw portions constituting the portions 42 and 43 expand and contract with each other, the transfer roller 11 can be easily removed from each of the bearings 40 and 41, and can be detached from the second holding member 27. In this manner, cleaning, inspection, or replacement of the transfer roller 11 can be easily performed. By performing the reverse operation, the transfer roller 11 can be easily engaged with the bearings 40 and 41.
[0091]
As described above, since the transfer device including the transfer roller 11 is detachably attached to the second holding member 27, as described above, the second holding member 27 is held in the first holding member as described above. After the transfer roller 11 is detached from the member 26, the transfer roller 11 is detached from the second holding member 27, and the transfer roller 11 can be cleaned or inspected, or only the transfer roller 11 can be replaced with a new one. Alternatively, the entire second holding member 27 with the transfer roller 11 still attached can be replaced with a new one.
[0092]
7, the second holding member 27 is detached from the first holding member 26, the second holding member 27 is taken out of the image forming apparatus main body through the opening 63, and the image forming unit is connected to the image forming unit. The drawing shows a state in which the second holding member 27 is pulled out of the image forming apparatus main body and removed from the image forming apparatus main body, as shown in FIG. Various components mounted on the rear plate 31 of the main body 1 of the image forming apparatus, for example, a gear 71 for rotating the photosensitive member as shown in FIG. 7 and a charging roller 6 shown in FIG. The lever 72 for bringing the photosensitive member 5 into and out of contact with the photosensitive member 5 and the solenoid 73 for driving the lever 72 can be easily repaired and inspected, or replaced. It is possible to enhance the maintainability of the elements on the back side of the image forming apparatus main body 1.
[0093]
The second holding member 27 removed from the first holding member 26 is used by being set on the first holding member 26. At the time of this setting, the second holding member 27 is inserted into the main body 1 through the opening 63 (FIG. 7) on the near side of the image forming apparatus main body 1, and the posture of the second holding member 27 with respect to the first holding member 26 in FIG. In this state, the connecting pin 37 on the rear side of the image forming apparatus main body shown in FIG. 6 is engaged with the receiving portion 35 on the rear side, and the connecting pin 36 on the front side of the main body of the image forming apparatus is also connected to the receiving portion on the front side. 34, the operator is located on the front side of the image forming apparatus main body 1 and engages the connecting pin 37 on the rear side with the receiving portion 35 while looking into the rear side inside the image forming apparatus main body. Therefore, these are very difficult to see, and the engaging operation is difficult.
[0094]
Therefore, in the image forming apparatus of the present embodiment, when the second holding member 27 is connected to the first holding member 26, a guide member for guiding the second holding member 27 is provided on the image forming apparatus main body side. In the illustrated example, as shown in FIGS. 7 and 12, a guide member 74 is fixed to the rear side plate 31 on the back side of the image forming apparatus main body 1. As shown in FIG. 12, when the connection pin 37 on the back side is fitted to the receiving portion 35, the connection pin 37 is aligned with the guide surface of the guide member 74 facing the first holding member 26, and It is lowered in the direction F and engaged with the receiving portion 35. In this manner, the connection pin 37, which is difficult to see on the back side, can be easily engaged with the receiving portion 34 to assemble them. The second holding member 27 can be easily and accurately assembled to the first holding member 26.
[0095]
Since the operator can directly see the front connecting pin 36, the image forming apparatus of this embodiment is not provided with a guide member for guiding the front connecting pin 36. However, the guide member is also provided on the front side. Can be provided.
[0096]
When the second holding member 27 with the transfer roller 11 attached thereto is delivered below the user as shown in FIG. 13, the transfer device protection cover 75 covering the transfer roller 11 is protected by the second transfer member 11 to protect the transfer roller 11. It is convenient to detachably attach to the holding member 27. The protective cover 75 illustrated here can easily move the cover 76 from the second holding member 27 by engaging a locking pin 76 protruding therefrom with a locking hole formed in the second holding member 27. It is locked lightly so that it can be detached from.
[0097]
Such a protective cover 75 can be used in place of the guide member 74 described above. That is, the second holding member 27 with the protective cover 75 attached is brought close to the first holding member 26 as shown in FIG. 13, and the surface 78 of the protective cover 75 facing the first holding member 26 is The second holding member 27 is lowered along the member 26, and the connecting pins 36, 37 thereof are engaged with the receiving portions 34, 35. Next, when the second holding member 27 is rotated to the second position shown in FIG. 4, the protective cover 75 is detached from the second holding member 27.
[0098]
As described above, in this embodiment, when the transfer device protection cover 75 detachably attached to the second holding member 27 connects the second holding member 27 to the first holding member 26, the second holding member 27 The guide member is also used as a guide member. According to such a configuration, the second holding member 27 can be easily assembled and set to the first holding member 26, and the dedicated guide member 74 is not required, so that the structure can be simplified and the cost can be reduced.
[0099]
As described above, the second holding member 27 is assembled to the first holding member 26 by using the guide member 74 shown in FIG. 12 or the transfer device protection cover 75 shown in FIG. In a state where the second holding member 27 is not correctly connected to the first holding member 26, the operator moves the second holding member 27 to the second position shown in FIG. Is rotated to the first position shown in FIG. 2 to perform the image forming operation, the transfer roller 11 does not correctly contact the photoconductor 5 and the contact is incomplete, and Images and jams may occur. In particular, since the rear connection pin 37 and the receiving portion 35 are difficult to see from the operator, the holding members 26 and 27 may be rotated to the first position without properly engaging them. .
[0100]
Therefore, in the image forming apparatus of the present embodiment, when the second holding member 27 is not correctly connected to the first holding member 26, an obstruction member that hinders the rotation of the first holding member 26 is provided on the image forming apparatus main body side. Is provided. For example, the obstruction member inhibits the rotation of the first holding member 26 to the first position.
[0101]
In the illustrated example, when the second holding member 27 is connected to the first holding member 26, the above-described guide member 74 that guides the second holding member 27 also serves as the obstruction member. That is, as shown in FIG. 12, the first holding member 26 may be turned to the first position shown in FIG. 2 in a state where the rear connection pin 37 is not correctly engaged with the receiving portion 35. Then, the connecting pin 37 interferes with the guide member 74, and the first holding member 26 cannot be rotated to the first position. Therefore, the operator can immediately know that the connecting pin 37 is not correctly engaged with the receiving portion 35, and restart the engaging work. As described above, it is possible to prevent an image forming operation from being performed without the second holding member 27 being correctly connected to the first holding member 26, and to prevent occurrence of a jam and occurrence of an abnormal image.
[0102]
Further, in this example, since the guide member 74 also serves as the obstruction member, the configuration can be simplified and the cost can be reduced.
[0103]
Here, when both the transfer roller 11 and the charge removing device 12 are to be replaced, the first and second holding members 26 and 27 are brought to the second position shown in FIG. 11, the second holding member 27 is removed from the first holding member 26 together with the transfer roller 11 and the static eliminator 12 as described above. Then, another second holding member 27 in which the new transfer roller 11 and the new static eliminator 12 are mounted is mounted and set on the first holding member 26 as described above. Alternatively, the transfer roller 11 and the static eliminator 12 whose life has expired are removed from the detached second holding member 27, and a new transfer roller 11 and a static eliminator 12 are assembled to the second holding member 27, and this is attached to the first holding member. 26.
[0104]
On the other hand, when removing only the static eliminator 12, the first and second holding members 26 and 27 are brought to the second position shown in FIG. 4, and the second holding member 27 is removed from the first holding member 26 without being removed. Only the static eliminator 12 can be removed from the second holding member 27. Only the charge removing device 12 can be removed without removing the transfer roller 12.
[0105]
As described above, since only the static eliminator 12 or the static eliminator 12 and the transfer roller 11 can be attached to and detached from the image forming apparatus main body, these components can be removed in the most efficient manner in response to a request for removal of each element. It can be attached and detached, and its workability can be improved. In addition, it is possible to replace only the static eliminator without any trouble while the transfer roller 11 is mounted on the image forming apparatus main body side.
[0106]
Next, a configuration relating to the attachment of the charge removing device 12 to the second holding member 27 and an example of an assembling method thereof will be clarified.
[0107]
As shown in FIGS. 6 and 14, a mounting hole 79 is formed in a portion of the second holding member 27 on the back side of the static elimination device mounting portion 57, and a locking hole 80 is formed in a wall portion on the front side thereof. Is formed. A lock piece 81 is integrally formed on the front side of the synthetic resin holder 15 in the static eliminator 12, and the lock piece 81 is integrally connected to the holder 15 and has a free end centered on the base end side. The side can be elastically deformed in the direction indicated by arrow G in FIG.
[0108]
When the static eliminator 12 is assembled to the second holding member 27, the rear end of the holder 15 is fitted into the mounting hole 79 on the rear side of the second holding member 27, and the front side of the holder 15. A locking claw 82 projecting from the lock piece 81 is engaged with a locking hole 80 on the near side of the second holding member 27. Thereby, the static eliminator 12 is assembled to the second holding member 27.
[0109]
When removing the static eliminator 12 from the second holding member 27, the first and second holding members 26, 27 are held at the second position shown in FIG. 4, and the lock piece 81 is free as shown in FIG. The locking piece 81 is elastically deformed by pushing the knob 83 attached to the end into the back side indicated by the arrow G with a finger, and the locking claw 82 is removed from the locking hole 80. Next, the operator rotates the static eliminator 12 around the end on the back side as shown by the reference numeral H in FIG. 14 while holding the finger on the knob 83, and returns to the position shown by the chain line in FIG. Bring. Next, by grasping the knob 83 and pulling the static eliminator 12 forward, the far end of the static eliminator 12 is pulled out of the mounting hole 79, and the static eliminator can be removed from the second holding member 27.
[0110]
In order to assemble and set the static eliminator 12 to the second holding member 27, the first and second holding members 26 and 27 are brought to the second position shown in FIG. 14 may be fitted into the mounting hole 79 as shown by a chain line in FIG. 14, and the front end of the holder 15 may be pressed down. As a result, the lock piece 81 is pressed against the wall on the front side of the second holding member 27 and is elastically deformed, and the locking claw 82 is locked in the locking hole 80.
[0111]
After removing the second holding member 27 from the first holding member 26, the charge removing device 12 can be attached to and detached from the second holding member 27 in the above-described procedure.
[0112]
As described above, the static eliminator 12 can be assembled to the second holding member 27 by a simple operation. At this time, the locking claw 82 of the static eliminator 12 is disengaged due to an incomplete operation by the operator. There is a possibility that the first and second holding members 26 and 27 are rotated to the first position shown in FIG. At the time of jam clearance, the worker's hand touches the static eliminator 12 set on the second holding member 27, and the locking claw 82 comes off from the locking hole 80. In this state, the first and second holding members are removed. It is conceivable that the members 26 and 27 are rotated to the first position.
[0113]
Here, if the image forming operation is performed without the static eliminator 12 being completely set on the second holding member 27 as described above, a problem that an abnormal image or a jam occurs is inevitable.
[0114]
Therefore, in the image forming apparatus of the present embodiment, when the static eliminator 12 is not properly mounted on the second holding member 27, the static eliminator 12 contacts the static eliminator 12 with the operation of the first holding member 26, Pressing means for pressing the static eliminator 12 to a proper position with respect to the second holding member 27 is provided. In the illustrated example, as shown in FIG. 8, this pressing means is constituted by a projecting portion 84 projecting from the unit case 4 of the image forming unit 2.
[0115]
The first and second holding members 26 and 27 are turned from the second position to the first position in a state where the locking claw 82 of the static eliminator 12 is disengaged from the locking hole 80 of the second holding member 27. Then, when they are set to the first position, the projection 84 of the unit case 4 presses the holder 15 of the static eliminator 12 from above, whereby the static eliminator 12 causes the static eliminator of the second holding member 27 to move. The locking device is pressed against the mounting portion 57, the locking claw 82 is correctly engaged with the locking hole 80, and the static eliminator 12 is set at a proper position with respect to the second holding member 27.
[0116]
As described above, even if the set state of the charge removing device 12 is incomplete, when the first and second holding members 26 and 27 are returned to the first position, the charge removing device 12 is automatically moved to the second holding member 27. In such a case, the image can be set correctly, and the occurrence of an abnormal image or a jam can be prevented.
[0117]
On the side of the image forming apparatus main body 1, a pressing means such as the above-described protrusion 84 can be provided.
[0118]
Further, as shown in FIGS. 2 and 6, the bearing holding portions 42 and 43 for holding the bearings 40 and 41 for the transfer roller 11 include a pair of holding claws projecting from the second holding member 27. When one of the holding claws is rotated by the rotation of the photoreceptor 5, it receives a pressure through the transfer roller 11, so that the holding claw is elastically deformed so as to fall in a direction indicated by an arrow I in FIG. , 41 may be impaired.
[0119]
Therefore, in the present embodiment, the static eliminator 12 is set at a position adjacent to the bearing holding portions 42 and 43. As a result, even if the photoconductor 5 rotates and an external force is applied to one of the holding claws constituting each of the bearing holding portions 42 and 43, the charge removing device 12 adjacent to the holding claw supports the holding claw, and the holding claw is moved. 2 can be prevented from being greatly deformed in the direction indicated by the arrow I. In this manner, the bearings 40, 41 can be reliably held by the bearing holding portions 42, 43.
[0120]
The first holding member 26 is movably supported with respect to the image forming apparatus main body 1. At this time, the first holding member 26 is moved downstream of the transfer roller 11 in the transfer paper transport direction as described above. The image forming apparatus main body is pivotally attached to the image forming apparatus main body 1 about a base end side of the image forming apparatus, and the first holding member is rotatable about a portion on the back side of the image forming apparatus main body as a base end. The first holding member is moved relative to the image forming apparatus main body by pivotally attaching to the image forming apparatus main body, or by supporting the first holding member on the image forming apparatus main body side so as to be able to move parallel to the photoconductor 5. It can be supported as much as possible.
[0121]
Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this, and can be variously modified and applied to various types of image forming apparatuses other than the illustrated form. You can do it.
[0122]
For example, the present invention can be applied not only to an image forming apparatus that forms a single color image such as a black image, but also to a color image forming apparatus that forms a multicolor image, particularly, a full-color image. Particularly, in a color image forming apparatus, for example, a plurality of image carriers composed of photoconductors are linearly arranged, toner images of different colors are formed on the respective image carriers, and a recording paper composed of, for example, transfer paper is formed. The present invention is also applicable to a color image forming apparatus in which a medium is sequentially passed through a transfer area of each image carrier, and at the time of passing the medium, a transfer device transfers a toner image on each image carrier to a recording medium.
[0123]
Further, for example, toner images of different colors are sequentially formed on an image carrier made of, for example, a photoreceptor, and each toner image is sequentially primary-transferred to a belt-shaped or drum-shaped intermediate transfer body, and then transferred to the intermediate transfer body. The present invention can also be applied to an image forming apparatus that performs a secondary transfer of the transferred toner image to a recording medium made of, for example, transfer paper. In this case, the transfer device of the present invention and its related configuration can be adopted as a configuration for primarily transferring a toner image on an image carrier such as a photoreceptor to an intermediate transfer member, and further, recording from the intermediate transfer member. The present invention is also applicable to a configuration for secondary transfer of a toner image to a medium. In the former case, a toner image on an image carrier made of a photoconductor is transferred to a recording medium made of an intermediate transfer body by a transfer device. In the latter case, the image carrier of the present invention is constituted by an intermediate transfer member, and the toner image on the image carrier is transferred to a recording medium made of, for example, transfer paper by a transfer device. .
[0124]
Further, a recording medium made of, for example, transfer paper is supported by being wound around a recording medium support made of, for example, a transfer drum, and a toner image formed on an image carrier made of, for example, a photoconductor is supported on the recording medium support. The present invention can be advantageously applied to an image forming apparatus of a type in which the image is transferred to a recording medium by a transfer device.
[0125]
Further, the image forming apparatus is not limited to an electronic copying machine, and may be configured as a printer, a facsimile, or a multifunction machine appropriately combining one or more of these functions. However, the present invention is not limited to this, and may be formed in a belt shape, or may be configured as a dielectric drum or a dielectric belt.
[0126]
As described above, in addition to the transfer roller, a corona discharger, a transfer brush, a transfer blade, and the like can be used as the transfer device. However, one transfer device is configured by appropriately combining these transfer devices. You can also.
[0127]
【The invention's effect】
According to the image forming apparatus of the first aspect, both the transfer device and the charge removing device can be attached to and detached from the image forming device main body, and only the charge eliminating device can be attached to and detached from the image forming device main body. In response to a request for the mode of attachment / detachment to the static eliminator, these can be attached / detached in the most efficient manner, and the workability thereof can be improved. It is possible to replace only the static eliminator while leaving the transfer device on the image forming apparatus main body side. Moreover, even if the setting of the static eliminator to the second holding member is incomplete, the operation of the first holding member can automatically set the static eliminator to the correct position with respect to the second holding member.
[0129]
According to the image forming apparatus of the second aspect, only the transfer device can be detached from the second holding member, and only the transfer device can be replaced.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view illustrating an entire configuration of an image forming apparatus.
FIG. 2 is a sectional view of an image forming unit and a transfer unit.
FIG. 3 is a front view showing a state in which first and second holding members are rotating from a first position to a second position, and the image forming unit is simplified by a chain line. FIG.
FIG. 4 is a front view similar to FIG. 3 when the first and second holding members occupy a second position.
FIG. 5 is a perspective view showing the transfer unit in a state where the first and second holding members are assembled together.
FIG. 6 is an exploded perspective view of the transfer unit.
FIG. 7 is a perspective view illustrating the inside of the image forming apparatus main body when the second holding member and the image forming unit are removed.
FIG. 8 is a perspective view illustrating a relative positional relationship between an image forming unit and a transfer unit.
FIG. 9 is a front view similar to FIG. 3, showing a specific example of an image forming apparatus in which a projection is not provided on a base plate.
FIG. 10 is a diagram illustrating an engagement state between a connection pin and a receiving portion.
FIG. 11 is a schematic front view showing a state where the second holding member is detached from the first holding member.
FIG. 12 is a schematic front view showing a state where the second holding member is assembled and set to the first holding member.
FIG. 13 is a schematic front view showing a specific example in which a transfer device protective cover is used as a guide member.
FIG. 14 is a cross-sectional view showing a relationship between a static eliminator and a second holding member into which the static eliminator is incorporated.
[Explanation of symbols]
1 Image forming apparatus main body
12 Static eliminator
13 Holder
26 First holding member
27 Second holding member

Claims (2)

An image forming apparatus that transfers a toner image formed on an image carrier to a recording medium by a transfer device and applies a charge eliminating operation to the recording medium by a static eliminator to separate the recording medium from the image carrier. A holding member for holding the apparatus, a first holding member movably supported with respect to the image forming apparatus main body, and a second holding member to which a transfer device is attached and which is detachably connected to the first holding member When the static eliminator is detachably mounted on the second holding member, and the static eliminator is not correctly mounted on the second holding member, the operation of the first holding member may be performed. An image forming apparatus comprising: a pressing unit that contacts the static eliminator and presses the static eliminator to a proper position with respect to the second holding member. The image forming apparatus according to claim 1, wherein the transfer device is detachably attached to the second holding member.

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