JP3622824B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus such as a printer, a facsimile, or a copying machine that forms an image on a recording material such as paper using electrophotographic technology. In particular, it relates to the frame configuration.
[0002]
[Prior art]
In general, an image forming apparatus that forms an image on a recording material such as paper using electrophotographic technology is a photosensitive member that is rotationally driven by a driving unit, and forms an electrostatic latent image on the surface by exposing the photosensitive member to the photosensitive member. Exposure means for developing, developing means for developing the electrostatic latent image into a toner image, transfer means for transferring the toner image to a recording material, feeding means for feeding the recording material to the transfer portion, A fixing unit configured to fix the toner image on the recording material by heating while passing the recording material onto which the toner image has been transferred by the transfer unit; and a conveying unit configured to convey the recording material on which the toner image is fixed. Yes.
[0003]
In the conventional image forming apparatus, the rotationally driven photoconductor and the exposure unit are supported by the same frame.
[0004]
[Problems to be solved by the invention]
In the conventional image forming apparatus, since the rotationally driven photoconductor and the exposure unit are supported by the same frame, vibration generated by the rotational drive of the photoconductor is transmitted through the same frame to the exposure unit. It was reaching.
[0005]
For this reason, the exposure position on the photosensitive member is affected by the vibration, and as a result, the formed image is adversely affected.
[0006]
SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can solve the above-described problems and suppress the adverse effects of vibration caused by rotational driving of a photoreceptor on an image.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an image forming apparatus according to claim 1, wherein the image forming apparatus is driven to rotate, and a first frame that supports a photoreceptor on which a toner image is formed by developing an electrostatic latent image formed on the surface; ,
A second frame that is separate from the first frame and supports an exposure unit that exposes the photosensitive member to form the electrostatic latent image;
The second frame is configured to be detachable from the first frame, and includes a lower frame and an upper frame that supports the exposure unit.
When the second frame is attached to the first frame, the upper frame floats from the lower frame.
[0008]
[Function and effect]
According to the image forming apparatus of the first aspect, the second frame that supports the exposure unit that exposes the rotationally driven photosensitive member to form an electrostatic latent image supports the rotationally driven photosensitive member. Since it is composed of a frame separate from the frame, the vibration generated by the rotational drive of the photosensitive member is transmitted to the first frame, but the vibration is further transmitted to the second frame supporting the exposure means. Things are hard to happen. At least the transmission of the vibration to the second frame supporting the exposure means is remarkably suppressed.
[0009]
Therefore, it is difficult for the vibration to reach the exposure unit, and the exposure position of the exposure unit on the photosensitive member is not easily affected by the vibration. As a result, the formed image is hardly adversely affected.
[0010]
In other words, according to the image forming apparatus of the first aspect, it is possible to suppress the adverse effect on the image due to the vibration caused by the rotation of the photosensitive member.
[0011]
Furthermore, since the second frame is configured to be detachable from the first frame, it is possible to facilitate the attaching / detaching operation of the photosensitive member by separating the second frame from the first frame. Become.
[0012]
In addition, the second frame includes a lower frame and an upper frame that supports the exposure means. When the second frame is attached to the first frame, the upper frame floats from the lower frame. On the other hand, it becomes possible to attach various members, devices, etc., in particular, devices serving as vibration generation sources.
[0013]
That is, even when an apparatus or the like that generates vibrations is attached to the lower frame, when the second frame is attached to the first frame, the upper frame that supports the exposure means floats from the lower frame. A situation in which the vibration from the source device is transmitted to the exposure means through the upper frame does not occur.
[0014]
Therefore, even when a device that is a vibration source is attached to the lower frame, the exposure position on the photosensitive member by the exposure unit is not affected by the vibration from the device, and as a result, the image quality of the formed image is improved. This can be further improved.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a schematic view showing an embodiment of an image forming apparatus according to the present invention, and FIG. 2 is a schematic view showing the frame configuration thereof.
[0017]
First, an outline of the image forming apparatus will be described.
[0018]
This image forming apparatus is an apparatus capable of forming a single color image and a full color image using a developing device using toners of four colors of yellow (Y), cyan (C), magenta (M), and black (K). .
[0019]
In FIG. 1, reference numeral 50 denotes a photoconductor unit, and the photoconductor 51 is rotationally driven in a direction indicated by an arrow by an appropriate driving means (not shown).
[0020]
The photoreceptor 51 has a thin cylindrical conductive substrate and a photosensitive layer formed on the surface thereof.
[0021]
Around the photoconductor 51, along the rotation direction, a charging roller 52 as a charging unit, an exposure unit 60 as an exposure unit, a developing unit 70 (Y, C, M, K) as a developing unit, an intermediate transfer A unit 80 and cleaning means 53 are arranged. The photoreceptor unit 50 includes a photoreceptor 51, a charging roller 52, and a cleaning unit 53.
[0022]
The charging roller 52 contacts the outer peripheral surface of the photoconductor 51 to uniformly charge the outer peripheral surface. On the outer peripheral surface of the uniformly charged photoconductor 51, the exposure unit 60 performs selective exposure L1 according to desired image information, and an electrostatic latent image is formed on the photoconductor 51 by this exposure L1. .
[0023]
The electrostatic latent image is developed with toner applied by the developing unit 70.
[0024]
As the developing units, a yellow developing unit 70Y, a cyan developing unit 70C, a magenta developing unit 70M, and a black developing unit 70K are provided. These developing units 70Y, 70C, 70M, and 70K are configured to be swingable, so that only the developing roller 71 of one developing unit can selectively contact the photosensitive member 51. Therefore, these developing devices 70 apply toner of any one of yellow, cyan, magenta, and black to the surface of the photoconductor 51 to develop the electrostatic latent image on the photoconductor 51.
[0025]
The developed toner image is transferred onto an intermediate transfer belt 86 that forms an intermediate transfer member of the intermediate transfer unit 80.
[0026]
The cleaning unit 53 includes a cleaner blade that scrapes off the toner remaining on and adhered to the outer peripheral surface of the photosensitive member 51 after the transfer, and a receiving portion that receives the toner scraped off by the cleaner blade.
[0027]
The intermediate transfer unit 80 includes a driving roller 81, four driven rollers 82, 83, 84, and 85, and an endless intermediate transfer belt 86 as an intermediate transfer member stretched around these rollers. doing.
[0028]
The drive roller 81 has a gear (not shown) fixed to the end thereof meshed with a drive gear (not shown) provided at the end of the photoconductor 51, so that the drive roller 81 has substantially the same circumference as the photoconductor 51. Accordingly, the intermediate transfer belt 86 is driven to circulate in the direction indicated by the arrow at substantially the same peripheral speed as that of the photoreceptor 51.
[0029]
The driven roller 85 is disposed at a position where the intermediate transfer belt 86 is pressed against the photosensitive member 51 by its own tension between the driven roller 81 and the primary roller at the pressure contact portion between the photosensitive member 51 and the intermediate transfer belt 86. A transfer portion T1 is formed. The driven roller 85 is disposed near the primary transfer portion T1 on the upstream side of the intermediate transfer belt 86 in the circulation direction.
[0030]
The driving roller 81 is provided with an electrode roller (not shown) via an intermediate transfer belt 86, and a primary transfer voltage is applied to the intermediate transfer belt 86 via this electrode roller.
[0031]
The driven roller 82 is a tension roller, and biases the intermediate transfer belt 86 in the tension direction by a biasing means (not shown).
[0032]
The driven roller 83 is a backup roller that forms the secondary transfer portion T2. A secondary transfer roller 88 as a secondary transfer unit is disposed opposite to the backup roller 83 via an intermediate transfer belt 86. The secondary transfer roller 88 can be brought into contact with and separated from the intermediate transfer belt 86 by a contact and separation mechanism (not shown). A secondary transfer voltage is applied to the secondary transfer roller 88.
[0033]
The driven roller 84 is a backup roller for the belt cleaner 89. The belt cleaner 89 includes a cleaner blade 89a that contacts the intermediate transfer belt 86 and scrapes off toner adhering to the outer peripheral surface thereof, and a receiving portion 89b that receives the toner scraped off by the cleaner blade 89a. ing. The belt cleaner 89 can be brought into and out of contact with the intermediate transfer belt 86 by a contact and separation mechanism (not shown).
[0034]
The intermediate transfer belt 86 is formed of a multilayer belt having a conductive layer and a resistance layer formed on the conductive layer and pressed against the photoreceptor 51. The conductive layer is formed on an insulating substrate made of synthetic resin, and a primary transfer voltage is applied to the conductive layer via the electrode roller described above.
[0035]
In the process in which the intermediate transfer belt 86 is circulated, the toner image on the photoconductor 51 is transferred onto the intermediate transfer belt 86 at the primary transfer portion T1, and the toner image transferred onto the intermediate transfer belt 86 is transferred to the secondary transfer belt 86. In the transfer portion T2, the image is transferred to a sheet (recording material) S such as paper supplied between the secondary transfer roller 88.
[0036]
The intermediate transfer unit 80 also incorporates the electrode roller, the urging means for the tension roller 82, the secondary transfer roller 88, and the belt cleaner 89.
[0037]
The recording material S is fed from a paper feeding device 90 serving as a paper feeding means, and is supplied to the secondary transfer portion T2 by a gate roller pair G at a predetermined timing. Reference numeral 91 denotes a paper feed cassette that holds the recording material S in layers, and 92 denotes a pickup roller.
[0038]
The recording material S on which the toner image is transferred at the secondary transfer portion T2 passes through the fixing unit 100 serving as a fixing unit, and the toner image is fixed.
[0039]
The fixing unit 100 includes a heating roller 101 having a heat source and a pressure roller 102 pressed against the heating roller 101, and heats the recording material S passing through the rollers 101 and 102 while sandwiching the recording material S therebetween. The toner image is melted and fixed on the recording material S.
[0040]
The recording material S that has passed through the fixing unit 100 is finally discharged onto the sheet receiving portion 41 formed on the case 40 of the apparatus main body through the paper discharge path 110. In addition, a reverse return path 110 ′ is provided that can reverse the front and back of the recording material S that has passed through the fixing unit 100 and return the recording material S to the secondary transfer portion T 2 again.
[0041]
The reverse return path 110 ′ is a switchback having two independent paper discharge paths 111 and 112 that can carry the recording material S that has passed through the fixing unit 100 and can reversely feed the recording material S once carried. A path 113 and a return path 114 for returning the recording material S fed back from the switchback path 113 to the secondary transfer portion T2 again. Therefore, the recording material S returned to the secondary transfer portion T2 again by the reverse return path 110 ′ is inverted and turned back to the secondary transfer portion T2.
[0042]
Such an image forming apparatus can form an image only on the front surface (first surface) of the recording material S, and can also form an image on both surfaces (first and second surfaces which are front and back surfaces). .
[0043]
Reference numeral 120 denotes a control unit, which constitutes control means for controlling the entire apparatus.
[0044]
The outline of the operation of the entire image forming apparatus as described above is as follows.
[0045]
(I) When a print command signal (image forming signal) from a host computer (not shown) or the like (personal computer or the like) is input to the control unit 120 of the image forming apparatus, the photosensitive member 51, each roller 71 of the developing device 70, and The intermediate transfer belt 86 is driven to rotate.
[0046]
(Ii) The outer peripheral surface of the photoconductor 51 is uniformly charged by the charging roller 52.
[0047]
(Iii) The exposure unit 60 selectively exposes L1 according to the image information of the first color (for example, yellow) on the outer peripheral surface of the uniformly charged photoconductor 51 to form an electrostatic latent image for yellow. Is done.
[0048]
(Iv) Only the developing roller of the developing device 70Y for the first color (for example, yellow) contacts the photoconductor 51, whereby the electrostatic latent image is developed, and the toner image for the first color (for example, yellow) Are formed on the photoreceptor 51.
[0049]
(V) A primary transfer voltage having a polarity opposite to the charging polarity of the toner is applied to the intermediate transfer belt 86, and the toner image formed on the photoreceptor 51 is transferred onto the intermediate transfer belt 86 at the primary transfer portion T1. The At this time, the secondary transfer roller 88 and the belt cleaner 89 are separated from the intermediate transfer belt 86.
[0050]
(Vi) After the toner remaining on the photosensitive member 51 is removed by the cleaning unit 53, the photosensitive member 51 is neutralized by the neutralizing light L2 from the neutralizing unit 61.
[0051]
(Vii) The operations (ii) to (vi) are repeated as necessary. That is, the second color, the third color, and the fourth color are repeated according to the content of the print command signal, and the toner images according to the content of the print command signal are superimposed on the intermediate transfer belt 86 to be intermediate. It is formed on the transfer belt 86.
[0052]
(Viii) The recording material S is supplied from the paper feeding device 90 at a predetermined timing, and immediately before or after the leading end of the recording material S reaches the secondary transfer portion T2 (in short, at a desired position on the recording material S, When the toner image on the intermediate transfer belt 86 is transferred), the secondary transfer roller 88 is pressed against the intermediate transfer belt 86 and a secondary transfer voltage is applied. Is a full color image in which toner images of four colors are superimposed) is transferred onto the recording material S. Further, the belt cleaner 89 contacts the intermediate transfer belt 86, and the toner remaining on the intermediate transfer belt 86 after the secondary transfer is removed.
[0053]
(Ix) When the recording material S passes through the fixing unit 100, the toner image is fixed on the recording material S, and then the recording material S is directed to a predetermined position (or to the sheet receiving portion 41 in the case of double-sided printing). In the case of double-sided printing, the paper is conveyed via the switchback path 113 toward the return path 114.
[0054]
That is, when an image is formed only on the front surface (first surface), the recording material S fed from the paper feeding device 90 has the image transferred to the first surface by the secondary transfer portion T2, and the fixing unit. After being fixed at 100, the sheet is discharged onto the sheet receiving portion 41 through the paper discharge path 111 or 112. In addition, a path switching means (not shown) is provided at the entrance portion 110A of the paper discharge paths 111 and 112, and this determines which paper discharge path (111 and 112) the recording material S is carried into. The
[0055]
When images are formed on both sides (the first side and the second side), the recording material S fed from the paper feeding device 90 has the image transferred to the first side by the secondary transfer portion T2 and fixed. After being fixed by the unit 100, it temporarily enters the paper discharge path 111 or 112 (switchback path 74), is reversely fed, passes through the return path 73, and again returns to the secondary transfer portion T2 at a predetermined timing by the gate roller pair G. The image is transferred back to the second side. Thereafter, the image is fixed on the second surface by the fixing unit 100 and is discharged onto the sheet receiving portion 41 via the paper discharge path 111 or 112.
[0056]
The outline of the image forming apparatus of this embodiment has been described above. Next, the frame configuration will be described.
[0057]
In FIG. 2, 10 is a first frame, 20 is a second frame, and 30 is a third frame. The first, second, and third frames 10, 20, and 30 are configured by different frames.
[0058]
The first frame 10 supports a photoconductor unit 50, a developing device 70 (Y, C, M, K), an intermediate transfer unit 80, and driving means (a driving motor, a gear or a gear train). . The photoconductor unit 50 and the intermediate transfer unit 80 are arranged side by side in the vertical direction. As will be described later, the photoconductor unit 50 and the intermediate transfer unit 80 are on the second frame 20 side with respect to the first frame 10. It is configured to be detachable from (right side in FIG. 2). Each developing device 70 is configured to be detachable from the first frame 10 from the third frame 30 side (left side in FIG. 2).
[0059]
The second frame 20 supports an exposure unit 60, a paper feeding device 90, and a gate roller pair G.
[0060]
The second frame 20 includes an upper frame 21 and a lower frame 22, and an exposure unit 60 is supported on the upper frame 21. A sheet feeding device 90, a pair of gate rollers G, and driving thereof are supported on the lower frame 22. Means (a gear train (not shown) for driving the pickup roller 92, the gate roller pair G, and the like) are supported. The sheet feeding device 90, the gate roller pair G, and the like generate vibrations when operating.
[0061]
The third frame 30 supports a fixing unit 100, a paper discharge path 110, and a reverse return path 110 ′.
[0062]
As shown in FIG. 3, the second frame 20 is configured to be separated from the first frame 10 in the horizontal direction (arrow X1 direction).
[0063]
As shown in FIG. 4, a hole 21b is provided in the bottom 21a of the upper frame 21 of the second frame 20, and a cylindrical member 22b with a flange 22d, which fits loosely into the hole 21b, is lowered by a screw 22c. The frame 22 is fixed to the upper plate 22a. The holes 21b, the cylindrical member 22b, and the like are provided at the four corners of the upper frame bottom plate 21a and the four corners of the lower frame upper plate 22a.
[0064]
Therefore, as shown in FIG. 4B, the upper frame 21 can be floated with respect to the lower frame 22. Reference numeral 22d denotes a shock absorber made of an elastic member such as rubber, which is used to reduce an impact when the upper frame 21 is placed on the lower frame 22.
[0065]
As shown in FIGS. 3, 5 and 6, positioning pins 12 as positioning members are provided on the second frame 20 side of the pair of side plates 11 of the first frame 10, respectively. An upper frame 21 of the frame 20 is provided with a holding mechanism 23 for holding the pins 12 and 12.
[0066]
The holding mechanism 23 is formed on the side plates 24 and 24 of the upper frame 21, and is taper grooves 24 a and 24 a as engaging portions that engage with and disengage from the pins 12 and 12, and is rotatably mounted on the side plates 24 and 24. Shaft 25, an operating lever 26 fixed to one end of the shaft 25, gears 27 and 27 inside the side plate 24 and fixed to the shaft 25, and a shaft 28a so as to mesh with the gears 27 and 27. A gear 28 rotatably attached to the side plate 24 and a holding claw 28b as a holding member for the pin 12 that rotates together with the gear 28 are provided.
[0067]
As shown in FIG. 3, when the second frame 20 is separated from the first frame 10, the tapered groove 24 a is located slightly below the pin 12 of the first frame 10, but the second frame 20 Can be engaged with the pin 12 of the first frame 10 when it is slid toward the first frame 10 (in the direction of the arrow X2).
[0068]
Therefore, when the second frame 20 is moved in the direction of the arrow X2 from the state shown in FIG. 3, the pin 12 enters the tapered groove 24a, so that the left side of the upper frame 21 (on the side facing the first frame 10 first) ) Is lifted. Next, as shown in FIG. 6, when the operation lever 26 is rotated in the direction of arrow a1, the gear 27 is also rotated in the same direction, so that the gear 28 and the holding claw 28b are rotated in the direction of arrow b1, The pin 12 is completely held by the end portion of the tapered groove 24a and the holding claw 28b.
[0069]
In this state, the upper frame 21 tries to turn clockwise about the pin 12 (refer to the direction of the arrow a1), but the side plate 24 of the upper frame 21 is connected to the first frame 10 as shown in FIG. Opposing bending portions 24b and 24b are provided, and a total of four contact pads 24c, which are made of an elastic body such as rubber, are provided on the bending portions 24b and 24b. Since the pad 24c contacts the receiving portions 11a and 11a provided on the side plate 11 of the first frame 10, the rotation is restricted.
[0070]
As a result, the upper frame 21 floats from the lower frame 22 as shown in FIG.
[0071]
At the same time, the pin 12 of the first frame 10 is completely held by the end portion of the tapered groove 24a and the holding claw 28b, and the contact pad 24c comes into contact with the receiving portion 11a of the first frame 10, whereby the second The frame 20 is accurately positioned with respect to the first frame 10.
[0072]
When the second frame 20 is separated from the first frame 10, if the operation lever 26 is rotated in the direction of the arrow a2 from the position shown in FIG. 3), the locked state of the pin 12 by the holding claw 28b and the end portion of the taper groove 24a is released, so that the second frame 20 is pulled out in the direction of the arrow X1 as shown in FIG. It can be separated from the frame 10. In the process of releasing the lock on the pin 12, first, the right side of the upper frame 21 moves downward, and then the engagement between the pin 12 and the taper groove 24a is released in the process of pulling out the second frame 20, The left side of the upper frame 21 is also moved downward. As a result, in the state shown in FIG. 3, the upper frame 21 is placed on the lower frame 22 as shown in FIG.
[0073]
A pair of operation levers 26 in the holding mechanism 23 can be provided. In this case, the shaft 25 does not necessarily have to connect the gears 27 and 27. Moreover, it can replace with the gear 27 grade | etc., And a holding mechanism can also be comprised with a suitable link mechanism etc. FIG.
[0074]
As shown in FIG. 3, a protrusion 29 that can be engaged with and disengaged from a pin (or roller, not shown) of the intermediate transfer unit 80 is provided at a portion of the lower frame 22 facing the intermediate transfer unit 80. ing. The protrusion 29 has an inclined portion 29a and a horizontal portion 29b. When the second frame 20 is attached to the first frame 10, the protrusion 29 moves the pin of the intermediate transfer unit 80 from the inclined portion 29 a to the horizontal portion 29 b, thereby swinging the intermediate transfer unit 80. The intermediate transfer belt 86 and the photosensitive member 51 are brought into contact with each other by swinging in the direction of the arrow c1 about the center shaft 80a, and the intermediate transfer unit 80 is positioned. Conversely, the second frame 20 is the first frame. When the intermediate transfer unit 80 is pulled out in the direction of the arrow X1, the pin of the intermediate transfer unit 80 runs down the inclined portion 29a from the horizontal portion 29b. The intermediate transfer belt 86 and the photosensitive member 51 are separated by being swung by their own weight.
[0075]
Therefore, as shown in FIG. 3, in the state where the second frame 20 is pulled out in the arrow X1 direction and separated from the first frame 10, the first transfer belt 86 and the photosensitive member 51 are not slidably contacted with each other. Using the space A1 between the frame 10 and the second frame 20, the photoreceptor unit 50 is pulled out as shown by the arrow X1 and lifted up as shown by the arrow Y1, so that it can be easily removed from the first frame 10. On the contrary, it can be easily mounted as shown by the arrows Y2 and X2. Similarly, the intermediate transfer unit 80 can be easily attached to and detached from the first frame 10 without causing the intermediate transfer belt 86 and the photosensitive member 51 to come into sliding contact with each other. The second frame 20 can be further separated in the X1 direction than the position shown in FIG. 3 (that is, to the extent that the intermediate transfer unit 80 can be pulled out from the first frame 10 in the arrow X1 direction). is there. Further, the shaft 80a serving as the swing center of the intermediate transfer unit 80 described above is configured to be able to be engaged with and disengaged from a receiving portion (not shown) of the shaft 80a provided at an appropriate position of the first frame 10.
[0076]
Further, since the feeding device 90 is separated from the first frame 10 together with the second frame 20, when the recording material is jammed between the paper feeding device 90 and the secondary transfer portion T2, The recording material can be easily removed using the space A1.
[0077]
As shown in FIG. 7, the third frame 30 is configured to be separated from the first frame 10 in the horizontal direction (arrow X2 direction). The third frame 30 has a horizontal frame 31 arranged in a substantially horizontal direction and a vertical frame 32 arranged in a substantially vertical direction, and one end portions of both frames are connected by a shaft 33. Thus, as shown in FIG. 8, the vertical frame 32 is configured to be rotatable around the axis 33 with respect to the horizontal frame 31. When the vertical frame 32 rotates as shown in FIG. 8, the vertical frame 32 and the fixing unit 100 are separated from each other.
[0078]
The horizontal frame 31 is mainly provided with a return path 114 of the reverse return path 110 ′ and driving means thereof (such as a gear train (not shown) that drives the transport roller R), and the vertical frame 32 has a reverse return path 110 ′. The switchback path 113 (which is also the paper discharge paths 111 and 112) and its driving means (a gear train (not shown) for driving the transport roller R) are mainly provided.
[0079]
The fixing unit 100 is attached to the horizontal frame 31, and is attached to and detached from the horizontal frame 31 in a substantially vertical direction (arrows Y1 and Y2) with the vertical frame 32 rotated as shown in FIG. It is configured to be possible.
[0080]
In the image forming apparatus having the reverse return path 110 ′, the recording material S that has been curled by passing once through the fixing unit 100 is reversely returned to the secondary transfer portion T2 (see FIG. 1). Therefore, the recording material S tends to be easily jammed in the reverse return path 110 ′.
[0081]
On the other hand, according to the image forming apparatus of this embodiment, as shown in FIG. 7, the third frame 30 is configured to be separated from the first frame 10 in the horizontal direction (arrow X2 direction). Therefore, the horizontal frame 31 is pulled out from the lower part of the first frame 10 in the direction of arrow X to expose the upper part 114a of the return path 114, and a space A2 is formed between the first frame 10 and the vertical frame 32. It becomes.
[0082]
Therefore, even if the recording material S is clogged in the return path 114, the recording material can be easily removed using the space A2.
[0083]
Further, as shown in FIG. 8, the vertical frame 32 is configured to be rotatable around the axis 33 with respect to the horizontal frame 31. Therefore, when the vertical frame 32 is rotated, the space A2 is further expanded and the vertical frame 32 is vertically expanded. A space A3 is formed between the frame 32 and the fixing unit 100.
[0084]
Therefore, when the recording material is jammed in the switchback path 113 (the paper discharge paths 111 and 112), the lower end of the recording material is picked using the space A3 and is easily removed as indicated by the arrow B. Can do.
[0085]
Moreover, since the fixing unit 100 can be removed from the horizontal frame 31 with the vertical frame 32 being rotated as shown in FIG. 8, the space A3 can be widened, and the upper portion 114a of the return path 114 can be increased. Can be exposed over a wider range.
[0086]
Therefore, the recording material jammed in the switchback path 113 or the return path 114 can be more easily removed.
[0087]
If the recording material is jammed between the secondary transfer portion T2 and the fixing unit 100, the recording material can be easily obtained by using the space A4 generated by the separation between the secondary transfer portion T2 and the fixing unit 100. Can be removed.
[0088]
Further, as described above, since the space A2 is formed between the first frame 10 and the third frame 30, each developing device 70 can be easily moved from the first frame 10 using this space A2. Detachable. The direction in which each developing device 70 is attached / detached is substantially the direction toward the center of the photoreceptor 51.
[0089]
As shown in FIGS. 8 and 9, the fixing unit 100 is provided with a lid 103 that can be opened and closed. FIG. 10 is a schematic perspective view of the fixing unit 100 with the lid 103 closed. FIG. 11 is a schematic perspective view of the fixing unit 100 with the lid 103 opened.
[0090]
As shown in FIG. 8, the lid 103 remains closed even when the vertical frame 32 is rotated.
[0091]
Therefore, as shown by an arrow B in FIG. 8, when removing the recording material jammed in the switchback path 113 (the paper discharge paths 111 and 112), the operator's hand touches the high-heated heating roller 101 or the like to cause a burn. There is nothing to do. If the recording material is jammed in the fixing unit 100, the recording material can be easily removed by opening the lid 103. In FIG. 10, reference numeral 104 denotes a slit-shaped opening through which the recording material S passes.
[0092]
According to the image forming apparatus as described above, the following effects can be obtained.
[0093]
(A) The second frame 20 that supports the exposure means 60 that exposes the rotationally driven photoreceptor 51 to form an electrostatic latent image is different from the first frame 10 that supports the rotationally driven photoreceptor 51. The vibration generated by the rotational drive of the photoconductor 51 is directly transmitted to the first frame 10, but the vibration is further transmitted to the second frame 20 supporting the exposure means 60. It becomes difficult to happen. Transmission of at least the above vibration to the second frame 20 supporting the exposure means 60 is significantly suppressed.
[0094]
Therefore, it is difficult for the vibration to reach the exposure unit 60, and the exposure position of the exposure unit 60 on the photosensitive member 51 is not easily affected by the vibration. As a result, the formed image is adversely affected. It becomes difficult.
[0095]
That is, according to the image forming apparatus of this embodiment, it is possible to suppress the adverse effect on the image caused by the vibration caused by the rotation of the photosensitive member 51.
[0096]
(B) Since the second frame 20 is configured to be detachable from the first frame 10, the photosensitive unit 50, that is, the photosensitive member 51 can be attached and detached by separating the second frame 20 from the first frame 10. Operation can be performed easily.
[0097]
(C) Moreover, the second frame 20 includes a lower frame 22 and an upper frame 21 that supports the exposure means 60, and when the second frame 20 is attached to the first frame 10, the upper frame 21 becomes the lower frame 22. Therefore, it is possible to attach a sheet feeding device 90 or the like serving as a vibration generation source to the lower frame 22.
[0098]
That is, when the second frame 20 is mounted on the first frame 10, the upper frame 21 that supports the exposure unit 60 is positioned below the lower frame 22, even though the paper feeding device 90 serving as a vibration generation source is attached to the lower frame 22. Since it floats from the frame 22, a situation in which vibration from the paper feeding device 90 serving as a vibration generation source is transmitted to the exposure means 60 via the upper frame 21 does not occur.
[0099]
Therefore, the exposure position on the photosensitive member 51 by the exposure unit 60 is not affected by the vibration from the paper feeding device 90, and as a result, the image quality of the formed image can be further improved.
[0100]
(D) Further, the first frame 10 supports the photosensitive member 51, the developing unit 70, the intermediate transfer member 86, and the driving unit thereof, and the second frame 20 different from the first frame 10 exposes the exposure unit. 60, and the fixing means 100, the paper discharge path 110, the reverse return path 110 ', and these driving means are supported by the third frame 30 different from the first and second frames. The vibration generated from the photosensitive member 51, the developing means 70, the intermediate transfer body 86, and the driving means, which are vibration generation sources, are directly transmitted to the first frame 10, and the vibration further supports the exposure means 60. The situation of being transmitted to the second frame 20 is less likely to occur. At least the transmission of the vibration to the second frame 20 is significantly suppressed.
[0101]
Similarly, the vibrations generated by the fixing means 100, the conveying means 110, and the like, which are vibration generation sources, and the driving means are directly transmitted to the third frame 30, but the vibration further supports the exposure means 60. The situation of being transmitted to the second frame 20 is less likely to occur.
[0102]
Therefore, it is difficult for the vibrations to reach the exposure unit 60, and the exposure position of the exposure unit 60 on the photosensitive member 51 is less affected by the vibrations. As a result, the formed image is adversely affected. Is more difficult to occur.
[0103]
That is, according to the image forming apparatus of this embodiment, it is possible to more reliably suppress the adverse effect of the vibrations caused by the respective means supported on the first and third frames 10 and 30 on the image.
[0104]
(E) The photoconductor unit 50 (that is, the photoconductor 51) and the intermediate transfer unit 80 (that is, the intermediate transfer body 86) are arranged in the vertical direction and supported by the first frame 10, and the second frame 20 is the first frame. Since the photoconductor unit 50 and the intermediate transfer unit 80 are configured to be detachable from the first frame 10 from the second frame 20 side. By separating the second frame 20 from the first frame 10, the photoconductor unit 50 and the intermediate transfer unit 80 can be easily attached to and detached from the first frame 10.
[0105]
That is, the second frame 20 is not rotated with respect to the first frame 10 but separated in the horizontal direction, so that the space A1 can be effectively formed between the first frame 10 and the second frame 20. By using this space A1, although the photoconductor unit 50 and the intermediate transfer unit 80 are arranged in the vertical direction with respect to the first frame 10, the photoconductor unit 50 and the intermediate transfer unit 80 are arranged. The unit 80 can be easily attached and detached.
[0106]
(F) The second frame 20 incorporates a feeding device 90 that feeds the recording material S onto which the toner image on the intermediate transfer body 86 is transferred, and this feeding device 90 together with the second frame 20. Since it is configured to be separated from the first frame 10, when the recording material is jammed between the paper feeding device 90 and the transfer position (secondary transfer portion T <b> 2) by the intermediate transfer body 86, the second frame 20. The recording material can be easily removed by separating the recording material from the first frame 10 in the horizontal direction.
[0107]
In addition, as described above, the second frame 20 is not rotated with respect to the first frame 10 but is separated in the horizontal direction, so that the space A1 is effectively formed between the first frame 10 and the second frame 20. By using the space A1, the jammed recording material can be easily removed.
[0108]
(G) Since the photoconductor unit 50, the developing device 70, and the intermediate transfer unit 80 are supported by the first frame 10, that is, the same frame, the relative positional accuracy of the photoconductor 51, the developing roller 71, and the intermediate transfer belt 86. And the development position and the transfer position are stabilized, so that the image quality is improved.
[0109]
Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of the gist of the present invention.
[0110]
【The invention's effect】
According to the image forming apparatus of the first aspect, it is possible to suppress an adverse effect on the image due to the vibration caused by the rotational driving of the photosensitive member.
[0111]
Further, the attachment / detachment operation of the photosensitive member can be facilitated.
[0112]
In addition, even when a device or the like as a vibration source is attached to the lower frame of the second frame, the exposure position on the photosensitive member by the exposure unit is not affected by the vibration from the device, resulting in formation. The image quality can be further improved.
[0113]
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an embodiment of an image forming apparatus according to the present invention.
FIG. 2 is a schematic diagram showing a frame configuration of an embodiment of an image forming apparatus according to the present invention.
FIG. 3 is an operation explanatory diagram.
4A and 4B are operation explanatory views, in which FIG. 4A is a partially enlarged sectional view of FIG. 3, and FIG. 4B is a partially enlarged sectional view of FIG.
FIG. 5 is a partially enlarged schematic cross-sectional view of FIG. 3;
FIG. 6 is an operation explanatory diagram.
FIG. 7 is an operation explanatory diagram.
FIG. 8 is an operation explanatory diagram.
FIG. 9 is an operation explanatory diagram.
FIG. 10 is a schematic perspective view of the fixing unit 100 with a lid 103 closed.
FIG. 11 is a schematic perspective view of the fixing unit 100 with a lid 103 opened.
[Explanation of symbols]
S Recording material
10 First frame
20 Second frame
21 Upper frame
22 Lower frame
30 3rd frame
51 photoconductor
60 exposure unit (exposure means)
70 Developer (Developer)
80 Intermediate transfer unit
86 Intermediate transfer belt (intermediate transfer member)
90 Paper feeder (paper feeder)
100 fixing unit (fixing means)
110 Paper discharge path (conveying means)
110 'reverse return path (conveyance means)

Claims (1)

A first frame that is driven to rotate and supports a photoreceptor on which a toner image is formed by developing an electrostatic latent image formed on the surface;
A second frame that is separate from the first frame and supports an exposure unit that exposes the photosensitive member to form the electrostatic latent image;
The second frame is configured to be detachable from the first frame, and includes a lower frame and an upper frame that supports the exposure unit.
An image forming apparatus, wherein the upper frame floats from the lower frame when the second frame is attached to the first frame.

Images