JP3747771B2 - Cleaning device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cleaning device that cleans the surface of a rotating body to be cleaned with a cleaning member that comes into contact with the surface. Specifically, a metal holding plate that holds the cleaning member is used as a plastic support structure. It relates to the improvement of the mounting part. In particular, the present invention relates to a cleaning device suitable as a cleaning device for an image carrier and an intermediate transfer member in an image forming apparatus represented by a printer, a copier, a facsimile machine, a multifunction machine, and the like.
[0002]
[Prior art]
In an image forming apparatus such as a printer or a copying machine using an electrophotographic system or the like, it remains after transfer on the surface of an image carrier such as a photosensitive member on which a toner image is formed or an intermediate transfer member on which the toner image is transferred. 2. Description of the Related Art A cleaning device that removes adhering matters such as adhering toner and performs cleaning is used.
[0003]
As illustrated in FIG. 10, the cleaning device 100 includes a cleaning member 110 such as a rubber blade on the surface of a rotating body 120 such as a drum-shaped or belt-shaped image bearing member, an intermediate transfer member, and the rotation axis direction thereof. There is known a type that scrapes and cleans deposits adhering to the surface by contacting over (Y). Moreover, as a cleaning apparatus using such a cleaning member 110, as illustrated in FIGS. 10 and 11, a holding plate (metal holder) made of a metal material such as a steel plate on which the cleaning member 110 is electrogalvanized. The holding plate 130 is fastened to the support structure (plastic housing, frame, etc.) 140 made of a plastic material such as ABS resin or glass resin-containing ABS resin by a fixing screw 150. There is a configuration that has been installed. Reference numeral 145 in the drawing denotes a support portion formed so as to place and support both end portions in the longitudinal direction of the holding plate 130. One screw hole 155 of the screw 150 is formed in each of the two support portions 145. Further, the holding plate 130 to which the cleaning member 100 is fixed is strongly supported by the fixing screw 150 with a tightening torque of about 0.5 (not including 0.5) to 0.7 N · m. It is firmly attached to the body 140.
[0004]
In the cleaning device 100 having such a structure, the support member 140 is attached and fixed to a predetermined support part (main body frame or the like) in the image forming apparatus so that the cleaning member 110 can be positioned as shown in FIG. The surface of the rotating body 110 is held so as to be stably in contact with the surface with a predetermined pressure contact force, so that deposits on the surface of the rotating body 120 can be reliably removed. At this time, the pressing force of the cleaning member 110 against the surface of the rotating body 110 is set by adjusting the amount of biting δ of the free end 110a of the cleaning member 110 to a predetermined value.
[0005]
[Problems to be solved by the invention]
Incidentally, the cleaning device 100 adopting the mounting structure as described above has the following problems. That is, a part of the plastic support structure 140 (such as the support part 150) or the whole of the cleaning device 100 is affected by a temperature rise due to operation in the main body (inside the apparatus) of the image forming apparatus. As shown in FIG. 12, the thermal expansion causes a slight deformation, resulting in a non-uniform cleaning performance of the cleaning member 110, or a cleaning failure such as spilling of toner scraped off by the cleaning member 110. There is a problem of doing.
[0006]
Such a cleaning failure is caused by the fact that the metal holding plate 130 has a different (small) coefficient of thermal expansion from the plastic support structure 140 while the deformation of the support structure 140 thermally deformed due to thermal expansion is small. The support structure 140 is not deformed and is not affected by the deformation of the support structure 140, but when the support image structure 140 is greatly deformed, the support structure 140 is finally tightened by the fixing screw 150. As a result, the cleaning member 110 fixed to the holding plate 130 is also deformed, so that the contact with the surface of the rotating body 120 is prevented. Even the contact state is caused by failure (non-uniformity).
[0007]
In addition, the deformation due to the thermal expansion of the support structure 140 at this time is mainly caused by the vertical direction (X) of the entire structure or the support portion 145 as illustrated by two-dot chain lines 140L and 140M in the lower part of FIG. It is a deformation | transformation which bends or twists in any one of these. In this case, the support portion 145 is deformed so as to rotate about the screw hole 155 (see FIGS. 11a and 12a), and the contact state of the cleaning member 110 with the rotating body 110 is in the rotation axis direction Y. It becomes a curved state deviating from the normal linear state along. In addition, as illustrated by two-dot chain lines 140D and 140U in the lower part of FIG. 11b, the entire support structure 140 or the support part 145 may be bent or twisted in any one of the horizontal front and rear directions (Z). There are some variations. In this case, the support portion 145 is deformed so as to be inclined with the axis of the screw hole 155 (dotted line in the figure) (see FIGS. 11b and 12b), and the contact state of the cleaning member 110 with the rotating body 120 is also rotated. The curve state deviates from the normal linear state along the axial direction Y. When the deformation of the support structure 140 is transmitted to the holding plate 130, the support attached with both end portions of the holding plate 130 being in close contact with each other regardless of the deformation pattern. It is often transmitted to follow the deformation state of the portion 145.
[0008]
Incidentally, in JP-A-5-53384, as a cleaning device for an image carrier in a process cartridge, a papermaking sheet that is in contact with the surface of the image carrier is attached to the frame via a sheet-attached sheet metal. In this case, in order to solve the problem that the frame body is thermally deformed due to the temperature rise and a gap is formed between the paper sheet and the image carrier and toner leakage occurs, reinforcing ribs are provided from the vicinity of the paper sheet attaching portion. It is shown that the frame is integrally formed. However, this solution is intended to prevent the thermal deformation of the frame itself by supplementing the strength against the heat of the frame with the reinforcement rib, but a space for forming the reinforcement rib is required. Therefore, it is disadvantageous for downsizing of the apparatus, and the reinforcement ribs must be integrally formed with the frame body, so that the manufacture of the frame body becomes complicated.
[0009]
The present invention has been made in view of such circumstances, and an object of the present invention is a cleaning device that cleans the surface of a rotating body with a cleaning member that comes into contact with the surface, and the cleaning member is a metal. As a cleaning device with a structure that is held by a plastic holding plate and that is attached to a plastic support structure by screwing, it is an obstacle to downsizing the device and manufacturing the support structure. An object of the present invention is to provide a cleaning device that can prevent the occurrence of defective cleaning due to thermal deformation of a support structure with a simple configuration.
[0010]
[Means for Solving the Problems]
The cleaning device of the present invention that can achieve the above-described object includes a metal holding plate that holds a cleaning member that is in contact with the surface of a rotating body over the direction of the rotation axis, and a longitudinal direction of the holding plate along the rotation axis direction. 1 is a screw hole formed in a support structure made of plastic corresponding to each end portion, and a fixing screw formed in each support portion from the holding plate side. In the cleaning device attached by tightening into the support structure, the support portion of the support structure has a form that protrudes around the screw hole, and the raised top portions are part of both ends of the holding plate. A seating surface portion having a configuration for mounting is provided, and the fastening torque of the fixing screw is within a range of 0.3 to 0.5 N · m (corresponding to 3 to 5 kgfcm). It is characterized in that the set.
[0011]
In such a cleaning device of the present invention, when the metal holding plate for holding the cleaning member is attached to the support portion of the plastic support structure by fastening with fixing screws, the both ends of the holding plate are attached. Since a part of the support portion is placed on the top portion (mounting surface) of the seat surface portion, the area of the contact portion between the both ends of the holding plate and the support portion is relatively small, and the fixing screw Since the tightening torque is relatively weak, the fixing of the holding plate to the support portion is relatively gentle. In other words, a slipping phenomenon in which the holding plate and the seating surface portion of the support portion rotate about the fixing screw can occur. For this reason, even if the support structure is thermally deformed, the influence (stress) of the deformation is not easily received due to the small contact area with the support portion of the holding plate, and the above-described holding plate and the seat portion of the support portion It is hardly absorbed (disappeared) by the sliding phenomenon between the two and becomes difficult to be transmitted to the holding plate. As a result, the cleaning member fixed to the holding plate is less likely to be deformed and the contact state (positional accuracy) with the rotating body is less likely to vary.
[0012]
Further, the seat surface portion in the cleaning device of the present invention is configured by a surface portion having a shape in which the mounting surface surrounds the screw hole and a linear surface portion along a short direction perpendicular to the longitudinal direction of the holding plate. Formed as is doing .
[0013]
This Thus, in the cleaning device of the present invention, The slip phenomenon between the holding plate and the seating surface portion of the support portion is generated stably by being supported by the linear surface portion along the lateral direction. This Result of Even when the support structure is thermally deformed, since the holding plate is stably supported by the linear surface portion along the short direction, the positional relationship of the cleaning member in contact with the rotating body is particularly varied. The holding plate is less likely to be displaced in the direction.
[0014]
The cleaning device of the present invention can be applied to any field as long as it needs to be cleaned with a cleaning member (such as an elastic blade) that makes the surface of the rotating body that rotates and abuts the surface of the rotating body with high accuracy. is there. In particular, when cleaning the drum-shaped or belt-shaped image carrier or intermediate transfer member in the image forming apparatus as described above, the contact accuracy (the amount of biting) of the cleaning member with respect to the surface of the image carrier or intermediate transfer member. , Contact pressure) is important from the standpoint of maintaining and stabilizing the cleaning performance and reducing the wear deterioration of the surface of the rotating body. Therefore, it is effective when applied as a cleaning device for such an image carrier or intermediate transfer body. It is.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
1 to 2 show Embodiment 1 of the present invention. FIG. 1 is a schematic view showing an image forming apparatus to which the cleaning apparatus of the present invention is applied. FIG. 2 is a cleaning apparatus according to Embodiment 1. FIG. 3 is a perspective view of the cleaning device (when it is detached), and FIG.
[0016]
The image forming apparatus intermediates four color toner images of yellow (Y), magenta (M), cyan (C), and black (K) formed individually by four image forming units 10Y, 10M, 10C, and 10K. It is possible to form a so-called full-color image by performing primary transfer so as to be superimposed on the surface of the intermediate transfer belt 20 of the transfer mechanism and then performing secondary transfer from the intermediate transfer belt 20 to the recording paper P side as a recording material. This is a possible color image forming apparatus. Further, this apparatus can also form a monochrome image or the like by operating only some of the four image forming units, for example, the black image forming unit 10K. .
[0017]
First, each of the image forming units 10 forms the toner images of the four colors described above by an electrophotographic process, and is in a state of being horizontally spaced at a substantially central portion of the image forming apparatus main body 1. It is arranged. Each of the image forming units 10 basically has a photosensitive drum 11 having an organic photosensitive layer or the like disposed on the outer peripheral surface of a drum that is rotationally driven at a predetermined speed, and the surface of the photosensitive drum 11. A charging roll 12 that is charged in this manner, an exposure device 13 as a latent image forming device that forms an electrostatic latent image by exposing the surface of the charged photosensitive drum 11 to light according to image information, and the electrostatic latent image. A developing device 14 that develops an image with a developer (toner) of a predetermined color, a primary transfer roll 15 that electrostatically transfers a toner image formed by the development to the intermediate transfer belt 20, and the surface of the photosensitive drum 11. And a drum-type drum cleaning device 16 for cleaning the drum.
[0018]
Among these, the exposure device 13 is housed in a housing sealed box 17 disposed on the lower side of the four image forming units 10, and is converted into image signals separated for each color from four semiconductor lasers (not shown). Laser beams LB-Y, LB-M, LB-C, and LB-K emitted in response to the rotary polygon mirror 18 through a predetermined optical system (lens or the like) are deflected and scanned, and then a plurality of unillustrated ones. Scanning exposure is performed obliquely from below on the respective photosensitive drums 11 facing each other through a single reflection mirror. Reference numeral 17a in the figure is a transparent window for transmitting and emitting the laser beams LB from the housing sealed box 17 toward the photosensitive drums 11 of the image forming units 10. Further, each developing device 14 supplies a developer (not shown) from toner cartridges 19Y, 19M, 19C, and 19K in which corresponding colors (Y, M, C, and K) of toner (developer) are respectively stored. It is designed to be replenished appropriately through the device. Further, a primary transfer bias having a polarity opposite to the charging polarity of the toner image on the photosensitive drum 11 is applied to the primary transfer roll 15 from a bias power supply device (not shown).
[0019]
In each of the image forming units 10, after the surface of the photosensitive drum 11 rotating in the direction of the arrow is uniformly charged by the charging roll 12, the image signal is color-separated from the exposure device 13 on the charged surface. The electrostatic latent image is written by scanning and exposing the laser beam LB corresponding to the laser beam LB, and then the latent image is developed with each color toner supplied from the developing device 14 to become a toner image. Finally, The toner images are sequentially primary transferred onto the surface of the intermediate transfer belt 20 passing between the photosensitive drum 11 and the primary transfer roll 15. Further, the surface of the photosensitive drum 11 after the transfer is cleaned by removing residual toner and the like by the blade of the drum cleaning device 16.
[0020]
Next, the intermediate transfer belt 20 has an endless shape having a two-layer structure in which a surface layer such as silicone rubber is laminated on a belt base material such as a polyimide film containing a conductive material and the like and adjusted in volume resistivity. A belt, which is stretched around a drive roll 21, a backup roll 22 of a secondary transfer unit, and a plurality of driven rolls 23, 24... And between the driven rolls 23, 24, the photosensitive drum of each image forming unit 10. 11 is in contact with each other, and is rotated in the direction of arrow B by the rotational power of the drive roll 21.
[0021]
Further, a secondary transfer roll 25 is disposed around the intermediate transfer belt 20 to press the intermediate transfer belt 20 against the backup roll 22 to form a pressure contact area of the secondary transfer portion. A power supply member 27 for supplying a secondary transfer bias having the same polarity as the charging polarity of the toner image on the intermediate transfer belt 20 from a bias power supply device (not shown) to the conductive shaft of the backup roll 22 is provided. It arrange | positions so that it may contact. Further, a blade type belt cleaning device 26 for cleaning the surface of the belt 20 is disposed at a position facing the drive roll 21 of the intermediate transfer belt 20.
[0022]
The toner image (multiple) transferred to the intermediate transfer belt 20 is conveyed to a secondary transfer portion facing the secondary transfer roll 25 arranged to face the backup roll 22 as the belt 20 rotates. Is done. The toner image on the intermediate transfer belt 20 is sent out by a paper feeding mechanism 31 from a paper storage tray 30 disposed below the exposure device 13 in accordance with the image formation and secondary transfer timing of the toner image. Then, electrostatic transfer is electrostatically transferred onto the recording paper P having a predetermined size that is conveyed to the secondary transfer portion through the paper conveyance path on which the resist roll 32 and the like are arranged. The surface of the intermediate transfer belt 20 after the secondary transfer is cleaned by removing residual toner and the like by the blade of the belt cleaning device 26. A one-dot chain line in FIG.
[0023]
In addition, the recording paper P on which the toner image is transferred from the intermediate transfer belt 20 is naturally peeled off from the intermediate transfer belt 20 portion when passing through the secondary transfer portion, and then pressed with the heating roll 36 in the fixing device 35. A member (pressure pad, pressure roll, etc.) 37 is sent so as to pass through the pressure contact area of the member 37 and subjected to heat fixing processing, and then discharged to the outside of the apparatus main body 1 (paper discharge accommodating portion 1a) by the discharge roll 38. Is done. A desired color image or the like is formed on the recording paper P through the above process.
[0024]
In this image forming apparatus, a cleaning device 26 for the intermediate transfer belt 20 having the following configuration is used.
[0025]
That is, as shown in FIGS. 2 and 3, the cleaning device 26 contacts the surface of the intermediate transfer belt 20 with a plastic housing 40 which is a support structure of the device to scrape residual toner and the like. The elastic blade 50 and a seal member 60 that fills the gap between the housing 40 and the intermediate transfer belt 20 are attached, and the residual toner scraped off by the elastic blade 50 is conveyed to a collection box (not shown). A rotary conveying member (auger) 70 is rotatably arranged. Of these, the elastic blade 50 and the seal member 60 are both screwed and attached to the housing 40 via metal sheet metals 55 and 65.
[0026]
The housing 40 is molded from a plastic material such as ABS resin, and as shown in FIGS. 3 and 4, at both ends of the main body 41 having a width wider than the width of the intermediate transfer belt 20. A support portion 42 for supporting both end portions of the metal sheet metal 55 holding the elastic blade 50 and a support portion 43 for supporting both end portions of the metal sheet metal 65 holding the sealing member 60 are formed. The auger 70 is rotatably accommodated on the lower side of the main body 41, and the conveyance path 44 for conveying the scraped toner and the like is mainly formed. Further, screw holes 42a and 43a of fixing screws 80 and 81 for screwing the metal plates 55 and 65 are formed in the support portions 42 and 43, respectively.
[0027]
In FIG. 2, reference numeral 45 denotes a pair of left and right seal blocks that are attached to fill the gaps between the cleaning device 26 (actually the housing 40) and the intermediate transfer belt 20 and the drive roll 21, and 46 denotes one end of the housing 40. A positioning support plate (supports one rotating shaft of the drive roll 21) for holding the positional relationship of the cleaning device 26 with respect to the drive roll 21 (strictly, the intermediate transfer belt 20). 47 is a mounting protrusion for positioning and mounting the cleaning device 26 (actually the housing 40) on the support frame of the image forming apparatus. The seal block 45 is attached to the housing 40 with a double-sided adhesive tape or the like. Reference numeral 75 denotes a drive transmission gear of the auger 70, which meshes with a gear of a rotation transmission mechanism (not shown).
[0028]
The elastic blade 50 functions as a cleaning blade, and is formed, for example, in a rectangular plate shape having a length corresponding to the entire width of the intermediate transfer belt 20 with polyurethane rubber. Further, the metal sheet metal 55 that holds the elastic blade 50 is a holding plate that is substantially L-shaped in section and is longer than the elastic blade 50 as shown in FIG. At both end portions 55a and 55b of the metal sheet metal 55, screw through holes 56 through which the fixing screws 80 are passed are formed. The lower end of the elastic brace 50 is fixed to the upper part of the metal sheet metal 55 by a bonding means such as an adhesive, whereby the elastic blade 50 has a free end whose upper end protrudes from the upper part of the metal sheet metal 55. It has become. On the other hand, the seal member 60 is made of a rectangular PET film having a length corresponding to the entire width of the intermediate transfer belt 20, and the metal sheet metal 65 having both ends supported by the support portions 43 of the housing 40. It is fixed to the lower end in a state of protruding downward.
[0029]
In the cleaning device 26, as shown in FIGS. 4 and 5 in particular, the support device 42 of the housing 40 that supports the metal sheet metal 55 to which the elastic blade 50 is fixed protrudes around the screw hole 56. A seating surface portion 90 having a form is provided. The seating surface portion 90 has a raised top portion as a mounting surface 91 for mounting a part of both end portions of the metal sheet metal 55. The height (the degree of bulging) of the seat surface portion 90 is not particularly limited and is appropriately selected, but is preferably about 0.1 to 0.5 mm.
[0030]
Further, in this embodiment, the seat surface portion 90 has a mounting surface whose surface 91 is a ring (annular) shape surrounding the screw hole 56 and a short direction perpendicular to the longitudinal direction (L) of the metal plate 55 ( S) and a linear surface portion 92 along the line S). In addition to this, the widths w1 and w2 in the longitudinal direction of the mounting surface (particularly the width w2 of the linear surface portion 92 along the short direction) are set to be within a range of 1 to 3 mm. Is preferred. Furthermore, if necessary, the mounting surface of the seating surface portion 90 may be configured to be subjected to a surface treatment that can adjust (reduce) the frictional resistance of the surface or to be provided with a member. . Examples of the surface treatment capable of adjusting the frictional resistance include a treatment for adjusting surface smoothness (surface roughness). On the other hand, examples of the member capable of adjusting the frictional resistance include sheet materials such as an OHP sheet.
[0031]
Moreover, in this cleaning device 26, in addition to the seat surface portion 90 provided on the support portion 43, the tightening torque when the metal sheet metal 55 is fastened to the seat surface portion 90 of the support portion 43 with the fixing screw 80. Is set within a range of 0.3 to 0.5 N · m. In order to perform screw fastening with such a tightening torque, for example, a screw tightening operation may be performed using a torque driver in which the torque is set within the above range.
[0032]
The cleaning device 26 having such a configuration, for example, rotatably arranges the auger 70 in the conveyance path portion 44 of the housing 40 and attaches the seal block 45 to substantially the center of both ends of the housing 40, The metal sheet metal 55 with the elastic blade 50 fixed to the support part 42 of the housing 40 is fixed by screwing with a fixing screw 80, and the metal sheet metal 65 with the seal member 60 fixed to the support part 43 of the housing 40 is fixed with the fixing screw 81. Assembled by screwing in. At this time, particularly when the metal plate 55 holding the elastic blade 50 is screwed, the tightening torque of the screw is within the above-described range. On the other hand, the tightening torque at the time of screwing the metal plate 65 holding the seal member 60 is not particularly limited.
[0033]
Then, the cleaning device 26 is mounted in a usable state by being attached to the support frame of the image forming apparatus via the positioning plate 46 and the attachment and projection 47. When the positioning plate 46 is attached, one rotation shaft of the drive roll 21 is inserted into and supported by the shaft support hole 46a. By mounting in this way, the elastic blade 50 has a predetermined bite amount δ on the intermediate transfer belt 20 supported by the drive roll 21 on the free end 50a side as shown in FIG. It arrange | positions in the state contact | abutted by predetermined contact pressure. Further, the seal member 60 is also disposed in a state in which its free end is in contact with the intermediate transfer belt 20 supported by the drive roll 21.
[0034]
In the cleaning device 26, as shown in FIG. 6, particularly when the metal sheet metal 55 holding the elastic blade 50 is attached to the support portion 42 of the plastic housing 40 by fastening with the fixing screw 80, Since part of both end portions 55a and 55b of the metal sheet metal 55 is placed on the top part (mounting surface 91) of the seating surface part 90 in the support part 42, the contact between the both end parts of the metal sheet metal 55 and the support part. Since the area of the portion is relatively small (corresponding to the surface area of the mounting surface 91), and the fastening torque of the fixing screw 81 is relatively weak, the fixing of the metal sheet metal 55 to the support portion 42 is also relatively gentle. It will be something.
[0035]
For this reason, even when the housing 40 is thermally deformed due to a temperature rise in the image forming apparatus, the influence (stress) of the deformation is that the contact area between the metal sheet metal 55 and the support portion 42 of the metal sheet metal 55 is narrow. In addition, it is almost absorbed (disappeared) by the occurrence of a sliding phenomenon that rotates about the fixing screw 80 between the metal sheet metal 55 and the seating surface portion 90 of the support portion 42. For this reason, the influence of the deformation is not easily transmitted to the metal sheet 55.
[0036]
Further, even if the housing 40 is deformed so as to be bent in a convex shape so that the shaft of the screw hole 42a is inclined due to thermal deformation, or deformed so as to be bent in a concave shape (see two-dot chain lines 140U and 140D in FIG. 11b), As shown in FIG. 6b, the end 55a (55b) of the metal sheet metal 55 is not in full contact with the support portion 42 and there is a gap E between the support portion 42 except for the seat surface portion 90. The slip phenomenon that occurs between the metal sheet 55 and the seating surface 90 of the housing 40 is not hindered and is not easily affected by the deformation force.
[0037]
Therefore, in the cleaning device 26, when the housing 40 is thermally deformed, the elastic blade 50 fixed to the metal sheet metal 55 is deformed or is in contact with the intermediate transfer belt 20 (the bite amount δ corresponding to the position accuracy). ) Does not fluctuate and is maintained in a substantially stable state, so that stable and good cleaning performance can be obtained.
[0038]
FIG. 7 shows the measurement results when the cleaning device 26 is used to test the state of the biting amount of the elastic blade 50 with respect to the temperature environment (that is, the stability of the contact state).
[0039]
In this test, the cleaning device 26 was left in the A zone environment (28 ° C., 89% RH) and the C zone environment (10 ° C., 15% RH) for 2 hours, and then the inner side of the elastic blade 50 in the longitudinal direction ( Device rear side) Each bite at the end (IN), the center near the inner end (IN-CEN), the center (CEN), the center near the outer end (OUT-CEN), and the outer end (OUT) The amount δ (mm) was measured once each. The biting amount δ is measured by removing the driving roll 21 of the intermediate transfer belt 20 and rotating the biting amount measuring rotary jig in which a large number of semi-disc-shaped pieces having different radii r in units of 0.1 mm are mounted side by side on the spindle. Instead, attach a tool (its support shaft is the same as the rotation axis of the drive roll), search for the top of the rotating jig that touches the tip of each part of the elastic blade 50, The bite amount δ at each part is calculated by applying the radius r to the formula “bite amount δ = (radius of the driving roll 21) − (the radius r of the measurement rotating jig)”. The condition of this test is that the metal plate 55 has a sheet metal height H (see FIG. 4b) at the lower bent portion having an L-shaped cross section of 8 mm, a longitudinal direction (L) length of 336 mm, and a thickness of 2 mm. A metal plate with dimensions was used. Further, as the seating surface portion 90, one having a height of 0.1 mm and width dimensions w1 and w2 (see FIG. 5a) in the longitudinal direction of the mounting surface 91 was formed to be 2.0 mm. Further, the tightening torque of the screw 80 was set to 0.5 N · m.
[0040]
In this case, if the difference in the amount of biting δ between the two zones is 0.4 mm or less in any part of the elastic blade 50, a practically acceptable level (that is, defective cleaning due to thermal deformation of the housing 40 occurs). Not level).
[0041]
For comparison, FIG. 8 shows a case where the support portion 42 of the housing 40 is a flat surface, the seat surface portion 90 is not provided, and the tightening torque of the screw 80 is 0.7 N · m (FIG. 8s). ) And in this case, only the tightening torque of the screw 80 is changed to 0.5 N · m, and the result when a similar test is performed is shown (FIG. 8 b).
[0042]
In the present embodiment, when the same test was performed except that the height H of the metal sheet metal 55 in the above test was changed to 11 mm, the difference between the two zones at that time was an average value smaller than 0.3 mm. (About 0.24 mm) was confirmed.
[0043]
[Other embodiments]
In the present invention, the seating surface portion 90 of the support portion 142 of the housing 40 of the cleaning device 26 includes, for example, a ring-shaped surface portion 92 whose mounting surface 91 surrounds the screw hole 42a as illustrated in FIG. 9a. (That is, do not form the linear surface portion 93 along the short direction (S) of the metal sheet 55). This is sufficient when the length of the metal sheet 55 in the short direction (S) is short. Further, as illustrated in FIG. B, the linear surface portion along the short direction (S) of the metal sheet metal 55 may be formed on both sides of the ring-shaped surface portion 92 surrounding the screw hole 42a. It may be formed well (surface portions 93 and 94), and may be formed so as to be separated from the ring-shaped surface portion 92 (surface portion 94).
[0044]
In the present invention, the surface portion 92 surrounding the screw hole 42a is not limited to the ring shape, and may be an ellipse, a polygonal shape, or the like as long as a similar effect can be obtained. Further, the surface portion 93 along the short direction (S) of the metal sheet metal 55 is not limited to a linear shape, and may be slightly bent or widened in the middle as long as the same action and effect are obtained. It may be a linear one.
[0045]
Furthermore, the present invention may employ a screw attachment structure similar to that of the elastic blade 50 of the belt cleaning device 26 for the blade of the cleaning device 16 for the photosensitive drum 11 according to the first embodiment.
[0046]
【The invention's effect】
As described above, according to the present invention, the support portion for the holding plate in the plastic support structure is provided with a seating surface portion having a specific form, and the tightening torque of the fixing screw for the holding plate is increased. Identify In addition, the seating surface portion is formed so that the mounting surface is constituted by a specific surface portion. Therefore, even when the plastic support structure is thermally deformed, it becomes difficult for the deformation to be transmitted to the metal holding plate holding the cleaning member, Furthermore, since the holding plate is stably supported by the linear surface portion along the short side direction of the mounting surface, the holding plate is displaced in a direction that particularly changes the positional relationship of the cleaning member in contact with the rotating body. It becomes difficult to do. As a result, it is possible to prevent or reduce the occurrence of poor cleaning due to thermal deformation of the support structure. In addition, such an effect can be realized with the simple configuration as described above, and since it is such a configuration, it may particularly hinder the downsizing of the device and the manufacture of the support structure. Absent.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a color image forming apparatus according to a first embodiment.
FIG. 2 is a perspective view showing a cleaning device according to the first embodiment.
3 is a cross-sectional view of a main part showing the configuration of the cleaning device of FIG. 2 and its periphery.
4A is an exploded side view showing a housing, an elastic blade, and a metal sheet metal of the cleaning device of FIG. 2, and FIG. 4B is a sectional view taken along lines Q1-Q1 and Q2-Q2 of FIG.
5A is a side (plan) view showing the configuration of a seating surface portion of a support portion in the housing of FIG. 4, and FIG. 5B is a cross-sectional view taken along line Q-Q in FIG. 5A.
6A is a side (plan) view showing a state in which a metal sheet metal is screwed to a support portion in the housing of FIG. 4, and FIG. 6B is a cross-sectional view taken along line Q-Q in FIG. .
FIG. 7 is a graph showing test results regarding the cleaning device according to the first embodiment;
FIG. 8 is a graph showing test results for two cleaning devices as comparative examples.
FIG. 9 is a side view (plan view) and sectional views showing another configuration example of the seating surface portion of the support portion in the housing.
FIG. 10 is a schematic perspective view and a cross-sectional view showing an example of a conventional cleaning device.
FIG. 11 is an explanatory view of a side surface, a cross-section, and the like showing an example of a modified state of a holding structure for a cleaning member and a support structure in a conventional cleaning device.
FIGS. 12A and 12B are a side view and a cross-sectional view illustrating a mounting state of the holding plate of FIG. 11 and a deformed state of the support structure.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Photosensitive drum (rotating body), 20 ... Intermediate transfer belt (rotating body), 16, 26 ... Cleaning device, 40 ... Plastic housing (support structure), 42 ... Instruction part, 42a ... Screw hole, 50 ... Elasticity Blade (cleaning member), 55 ... Metal sheet metal (holding plate), 55a, 55b ... Both ends, 80 ... Fixing screw, 90 ... Seating surface part, 91 ... Mounting surface, 92-94 ... Surface part, L ... Longitudinal direction, S: Short direction.

Claims (2)

Supporting parts that support both ends of the holding plate in the longitudinal direction along the rotation axis direction of the metal holding plate that holds the cleaning member that contacts the surface of the rotating body in the direction of the rotation axis are provided at each end. In a cleaning device formed by attaching a fixing screw to a correspondingly formed plastic support structure by inserting and fastening one screw hole formed in each support portion from the holding plate side,
A seating surface portion having a configuration in which the supporting portion of the supporting structure is raised with the screw hole as a center and the raised top portion is a mounting surface on which part of both end portions of the holding plate is placed. And the tightening torque of the fixing screw is set within a range of 0.3 to 0.5 N · m ,
And the said seat surface part was formed so that the said mounting surface might be comprised by the surface part which consists of a shape which surrounds the said screw hole, and the linear surface part along the transversal direction orthogonal to the longitudinal direction of the said holding plate . A cleaning device characterized by that. The cleaning apparatus according to claim 1, wherein the rotating body is at least one of an image carrier and an intermediate transfer body in an image forming apparatus that forms a toner image .

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