JP4681933B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an electrophotographic or electrostatic recording type image forming apparatus used as a copying machine or a printer.

  A conventional image forming apparatus uses an intermediate transfer belt as an intermediate transfer member. The intermediate transfer belt is stretched around a tension roller, a driving roller, and a secondary transfer counter roller, and is driven to rotate in a state where tension is applied to the intermediate transfer belt by the tension roller. The tension roller applies a predetermined tension to the intermediate transfer belt by urging the central axis by a spring.

  If the intermediate transfer unit including the intermediate transfer belt is left with a tension applied to the intermediate transfer belt during transportation and storage when shipped together with the image forming apparatus, the intermediate transfer unit may be wound around the roller. Since a problem of causing a transfer defect occurs when forming the film, the tension is released before shipping.

With respect to preventing the intermediary transfer belt from clinging, there has been disclosed an invention for loosening the tension (for example, Patent Document 1 and Patent Document 2).
Japanese Patent Laid-Open No. 07-29395 JP 2000-231275 A

  In the above-described conventional configuration, the pressure release member that temporarily fixes the position of the tension roller in a state where the tension of the intermediate transfer belt is loosened needs to be removed by the user or service person when the apparatus is installed. Accordingly, when the removal of the pressure release member is forgotten, a predetermined tension is not applied to the intermediate transfer belt, which may cause slippage of the intermediate transfer belt during image formation and cause image defects.

  In addition, even in a configuration in which the tension roller is moved by operating a lever or the like to loosen the tension of the intermediate transfer belt, it is necessary to operate a dedicated lever for applying tension at the time of installation, and there is a special mechanism for that purpose. It was necessary and the cost was rising.

In order to achieve the above object, an image forming apparatus according to the present application is an endless belt body, a plurality of stretching members that stretch the belt body , and one of the plurality of stretching members. A tension roller biased by a biasing means for applying a pressing force in a direction from the inside to the outside of the belt body, and a shaft of the tension roller biased by the biasing means A belt unit comprising: a regulating unit that regulates a position of the belt body; and a cleaning device that includes a cleaning blade that contacts an outer surface of the belt body in order to clean the toner on the belt body, and the belt unit is a device. a detachable relative to the body, the tension roller by can be released imparting the pressing force to said belt body image shape by the regulating means In the device, a connecting member for connecting the cleaning device and the belt unit, wherein the cleaning device has a working portion for moving the regulating means, the regulating means, about the axis of the tension roller It has a restricting part that is rotatable and has one end contacting the action part and the other end restricting the position of the shaft of the tension roller, and the cleaning member is moved to a predetermined position with respect to the belt body by the connecting member. When the contact portion comes into contact, the action portion comes into contact with one end of the restricting means, so that the restricting means rotates, and the restriction on the shaft of the tension roller by the other end of the restricting means is released by the turning. Thus, the tension roller is applied to the belt body from a state in which the application of pressure to the belt body is released by the restriction member. Characterized in that it shifts to a state of applying pressure.

  The invention according to the present application can apply tension to the belt body with a simple and reliable operation. More specifically, the present invention has an effect that the tension of the belt that has been loosened at the time of shipment can be applied simultaneously with the operation of mounting the contact means when the image forming apparatus is installed. Therefore, it is possible to prevent a mistake that an image is formed while the tension is loosened, and to suppress printing of a defective image. Moreover, it has the effect that a user's installation work load can be reduced.

Example 1
1 to 12 show an embodiment of the present invention. First, an embodiment of an image forming apparatus in which an embodiment of the present invention is embodied will be described with reference to FIG.

  The image forming apparatus of this embodiment can attach and detach process cartridges 10y, 10m, 10c, and 10k for four colors to the corresponding development forming stations, and can irradiate laser light to optical devices 20y, 20m, 20c, and 20k. , An intermediate transfer body unit 30, a transfer material transport unit 40, a fixing unit 50, and the like.

  Each of the process cartridges 10y, 10m, 10c, and 10k has the same structure, and is an electrophotographic photosensitive member. A photosensitive drum 12, an image carrier, a charging unit 13, and a developing unit 14 are integrally configured.

  The intermediate transfer body unit 30 that is a belt unit includes an intermediate transfer belt 31 that is an endless belt body, three rollers that are tension members that rotatably support the intermediate transfer belt 31, a driving roller 32, a tension roller 33, The secondary transfer counter roller 34, the primary transfer roller 35 that transfers the toner image formed on each photosensitive drum 12 to the transfer belt 31, and the toner image transferred on the transfer belt 31 are further transferred to the transfer material p. A next transfer roller 36 is provided. Since the tension roller 33 is pressed from the inside to the outside of the intermediate transfer belt 31 and is movably attached, the tension roller 33 exerts a certain tension on the intermediate transfer belt 31. The transfer material transport unit 36 includes a pickup roller 43, a paper feed roller 44, a transport roller 45, a registration roller 46, and the like that transport the non-transfer material p from each paper feed cassette 41 or paper feed tray 42 to the secondary transfer region. ing.

  The fixing unit 50 includes a fixing roller 51 and a pressure roller 52, and performs fixing by applying heat and pressure to the toner image on the transfer material p.

  In the above configuration, first, in the process cartridge 10y of the first color, for example, yellow, the photosensitive drum 12 is uniformly charged by the charging unit 13, and then a latent image is formed by the laser light emitted from the optical unit 20y. The image is developed by the developing means 14 to form a toner image.

  The toner image formed on the photosensitive drum 12 is primarily transferred onto the intermediate transfer belt 31 which is also an image carrier by the action of the primary transfer roller 35.

  A similar image forming process is performed in each of the process cartridges 10m, 10c, and 10k for m, c, and k to form toner images of the respective colors and are sequentially transferred onto the previously formed toner images.

  On the other hand, the transfer material p is transported from the paper feed cassette 41 or the paper feed tray 42 to the secondary transfer region by the transfer material transport unit 40, and the toner image formed on the intermediate transfer belt 31 by the action of the secondary transfer roller 36 is formed. Transferred onto the transfer material p. At this time, the waste toner remaining on the intermediate transfer belt 31 without being completely transferred is removed by the cleaning device 60 which is also a contact means for contacting the intermediate transfer belt 31. More specifically, the intermediate transfer belt 31 is used for the next image formation by being removed by a cleaning blade 61 which is a contact member formed in a cleaning device 60 which is a cleaning unit. The removed waste toner is collected in a waste toner container unit 80. The transfer material p onto which the toner image has been transferred is conveyed to the fixing unit 50, where the toner image is fixed at the nip portion between the fixing roller 51 and the pressure roller 52, and is discharged onto the discharge tray 56 by the discharge roller 55. The

  Next, the intermediate transfer unit and the cleaning device 60 will be described with reference to FIGS.

  First, as shown in FIG. 3, the intermediate transfer unit 30 includes an intermediate transfer belt 31, a drive roller 32, a tension roller 33, a secondary transfer counter roller 34, a primary transfer roller 35, and a roller support device 100 that supports these rollers. Has been. The cleaning device 60 includes a cleaning blade 61, a pressure spring 62, a conveying screw 63, a cleaner case 64 for holding them, and the like.

  In the cleaning device 60, the cleaning blade 61 is made of urethane rubber and fixed on the support metal plate 65. The support metal plate 65 is configured to oscillate around the oscillation center shaft 66 held by the cleaner case 64 by pressing of the pressure spring 62, and the cleaning blade 61 contacts the intermediate transfer belt 31. The cleaning device 60 is positioned so that the tension roller 33 is disposed opposite the point where the cleaning blade 61 contacts the intermediate transfer belt 31, and the intermediate transfer belt 31 bends due to the contact pressure of the cleaning blade 61. In other words, the cleaning blade 61 can be brought into contact with the intermediate transfer belt 31 at a predetermined contact angle and a predetermined contact pressure.

  At the bottom of the cleaner container 64, a conveying screw 63 configured to convey the collected toner forward in FIG. 3 is installed. As shown in FIG. 4, a screw input 67 is connected to the rear end side of the conveying screw 63. Further, a coupling 160 shown in FIG. 10 that receives a driving force from a motor (not shown) is provided on the rear side in FIG. Thus, the conveying screw 63 is rotated by transmitting the driving force of the motor to the screw input 67 through the coupling 160.

  Next, the configuration for positioning the cleaning device 60 on the intermediate transfer body unit 30 will be described with reference to FIGS.

  First, referring to FIGS. 4, 5, and 6, the positioning and supporting structure of the connecting members 220 and 220 ′ on the intermediate transfer body unit 30 will be described. 220 is before the connecting member, 220 ′ is after the connecting member, 221 and 221 ′ are CL latch shafts, 225 and 225 ′ are tension roller shaft fitting grooves, 222 is a first positioning elongated hole, 223 is a CL positioning shaft, 226 Is a retaining groove, 300 is a tension roller shaft retaining member, 38 is a tension roller shaft, 100 is a roller support device, 108 is a connecting member positioning shaft, and 107 is a tension spring.

  First, the positioning configuration of the connecting members 220 and 220 'with respect to the intermediate transfer body unit 30 will be described. CL latch shafts 221 and 221 ′ for positioning and fixing the cleaning device 60 on the front 220 and the rear 220 ′ of the connecting member, and the connecting member positioning shaft 108 provided on the tension roller shaft 38 and the roller support device 100. Tension roller shaft fitting grooves 225 and 225 'are fitted. The tension roller shaft fitting grooves 225 and 225 ′ are formed so that one end is opened, and the other end is formed in a semicircular arc shape that fits the tension roller shaft 38. Further, a first positioning elongated hole 222 is provided in the rear 220 'of the connecting member, and two CL positioning shafts 223 are provided in the front 220 of the connecting member.

  When the intermediate transfer body unit 30 is mounted in the direction of the arrow in FIG. 4, both ends of the tension roller shaft 38 and the connecting member positioning shaft 108 are connected to the tension roller shaft fitting grooves 225, 225 ′ at the front 220 of the connecting member and the rear 220 ′ of the connecting member. To fit each. At this time, the axis T of the tension roller shaft 38 and the line U connecting the centers of the semicircular arc shapes of the tension roller shaft fitting grooves 225 and 225 'coincide with each other. As a result, the positions of the front 220 and the rear 220 'of the connecting member relative to the intermediate transfer body unit 30 are determined based on the tension roller shaft 38.

  Next, means for supporting the connecting members 220 and 220 'on the tension roller shaft 38 will be described. As shown in FIG. 5, a flange 302 larger than the guide shaft 301 is provided at the tip of the guide shaft 301 provided in the tension roller shaft retaining member 300. The connecting member 220 is provided with a retaining groove 226, and an opening 227 that is one size larger than the flange 302 is provided below the retaining groove 226. Therefore, when the tension roller shaft retaining member 300 is moved upward after the flange 302 has entered from the opening 227, the guide shaft 301 fits into the retaining groove 226, and the tension roller shaft is moved along the retaining groove 226. The stopper 300 is configured to be slidable.

  In addition, a flange mounting hole 311 is provided in the connecting member support sheet metal 310 fixed to the image forming apparatus. When the flange 302 is installed in the flange mounting hole 311 with the guide shaft 301 fitted in the retaining groove 226, the flange 302 is configured to be caught on the outer periphery of the flange mounting hole 311.

  Thus, the connecting member 220 is supported roughly so as to hang from the connecting member support sheet metal 310 via the tension roller shaft stopper 300. Furthermore, the tension roller shaft retaining member 300 can be prevented from falling off the flange mounting hole 311 by closing the flange mounting hole 311 from above with a cover (not shown). Although the front side of the tension roller 33 has been described with reference to FIGS. 5 and 6, the connecting member 220 ′ and the tension roller shaft stopper 300 are roughly supported on the rear side by the same configuration.

  Here, the intermediate transfer member unit 30 can be moved up and down in the vertical direction of FIG. 3 by a mechanism (not shown) together with the connecting member front 220, the connecting member rear 220 ′, and the cleaning device 60, and the photosensitive drum 12 and the intermediate transfer belt. The configuration is such that 31 can be separated. Further, the intermediate transfer body unit 30 is configured to be detachable from the side surface of the image forming apparatus. In other words, the intermediate transfer body unit 30 is lowered to the lower side in FIG. 3 when attaching and detaching, so that the surface of the photosensitive drum 12 and the intermediate transfer belt 31 are not damaged.

  That is, as shown in FIG. 6a, the connecting members 220 and 220 'are positioned above in the state where the intermediate transfer body unit 30 is mounted. At this time, the tension roller shaft retaining member 300 is positioned below the retaining groove 226 and is fitted to the tension roller shaft 38 in the left-right direction.

  Accordingly, the tension roller shaft 38 is fitted in the vertical direction by the tension roller shaft fitting grooves 225 and 225 ′, and is fitted in the left and right direction by the tension roller shaft retaining member 300, thereby fixing the connecting members 220 and 220 ′. Is made.

  On the other hand, when the intermediate transfer body unit 30 is removed as shown in FIG. 6B, the connecting members 220 and 220 'are positioned below. At this time, the tension roller shaft retainer 300 is regulated by the lowermost surface 312 of the flange mounting hole 311 and is positioned above the retainer groove 226, and on the path where the tension roller shaft 38 enters the tension roller fitting grooves 225, 225 ′. Is not.

  Incidentally, as shown in FIG. 7, bearings 101 are arranged at both ends of the tension roller shaft 38, and the tension roller 33 is fitted into the tension long hole 102 provided in the roller support device 100, so that the tension roller 33 is 7 is configured to be movable in the horizontal direction. Although the front side of the tension roller 33 has been described with reference to FIG. 7, the rear side has the same configuration.

  Further, a tension spring 107 and a spring receiving shaft 105 provided in the roller support device 100 are provided on the tension roller 33 in order to stretch the intermediate transfer belt 31 stretched around the driving roller 32 and the secondary transfer counter roller 34 without looseness. By arranging between the tension spring receivers 106 arranged at both ends of the tension roller shaft 38, a force is applied to the tension roller 33 in the horizontal direction in FIG.

  Even if the position of the tension roller 33 moves along the tension long hole 102 by these, since the position of the connecting member 220 is determined with respect to the tension roller shaft 38, the axis T of the tension roller shaft 38 and the CL latch A line T ′ connecting the axes of the axes 121 and 121 ′ is always kept parallel.

  Next, referring to FIGS. 4, 8, and 9, the positioning configuration of the cleaning device 60 on the connecting member 220 and the intermediate transfer body unit 30 will be described. 8 shows positioning and fixing of the cleaning device 60 to the rear 220 'of the connecting member, and FIG. 9 shows positioning and fixing of the cleaning device 60 to the front 220 of the connecting member. 140 is a cleaner upper guide, 141 is an upper groove, 150 is a cleaner lower guide, 151 is a lower groove, 71 is a positioning member, 79a is a positioning hole, 79b is a second positioning slot, 73 is a third positioning slot, 72 is A discharge guide, 67 is a screw input, and 74 is a latch groove.

  First, as shown in FIGS. 8a and 9a, the cleaning device 60 is guided by the upper groove 141 and the lower groove 151 and inserted into the image forming apparatus main body. Then, as shown in FIG. 8b, the screw input 67 is inserted into the first positioning slot 222 provided in the rear 220 'of the connecting member. At the same time, as shown in FIG. 9b, with respect to the two CL positioning shafts 223a and 223b installed on the front side of the connecting member 220, the positioning holes 79a provided in the positioning member 71 provided in the cleaning device 60, the second The positioning elongated holes 79b are fitted with each other.

  The positioning member 71 is rotatably attached to the discharge guide 72 of the cleaning device 60, and the position of the third positioning elongated hole 73 that is the rotating portion of the cleaning device 60 with respect to the tension roller 33 is determined. Sometimes, it is formed as a long hole that has the same phase as the first positioning hole 222.

  As shown in FIG. 4, the screw input 67 and the discharge guide 72 are centered on the same axis S. Accordingly, the cleaning device 60 rotates about an axis S formed by the center of the screw input 67 and the discharge guide 72, so that the CL latch shaft 221 installed on the connecting member 220, as shown in FIGS. 8c and 9c, 221 'fits into the latch grooves 74 and 74' of the cleaning device 60, and is positioned and fixed with respect to the connecting member by latches 75 and 75 'biased by a spring (not shown).

  As described above, the position of the cleaning device 60 relative to the intermediate transfer unit 30 is determined based on the tension roller 33 via the connecting members 220 and 220 '. As a result, even when the position of the tension roller 33 moves, the cleaning blade 61 moves in conjunction with the tension roller 33 and can always contact the intermediate transfer belt 31 with a constant pressure. Good cleaning performance can be maintained at low cost.

  Unnecessary waste toner such as toner remaining on the intermediate transfer belt 31 without being completely transferred to the transfer material P by the secondary transfer roller 34 is removed from the intermediate transfer belt 31 by the cleaning blade 61 and collected in the cleaner container 64. Then, the toner is conveyed forward in FIG. 3 by the conveying screw 63, discharged from an opening 72 ′ provided in the discharge guide 72 shown in FIG.

  Here, a configuration relating to the guidance of the cleaning device 60 to the image forming apparatus main body will be described with reference to FIGS. FIG. 10 shows the insertion of the cleaning device 60 as viewed from the side of the image forming apparatus. Reference numeral 132 denotes a stay, 140 denotes an upper guide, 150 denotes a lower guide, 77 denotes an upward convex guide, 78 denotes a downward convex guide, and 76 denotes a handle.

  The stay 132 is accurately positioned, supported and fixed between the front plate 130 and the rear plate 131, and a cleaner lower guide 150 is installed on the stay 132. The cleaner upper guide 140 is installed on the front plate 130. An upper groove 141 is formed in the cleaner upper guide 140, and a lower groove 151 is formed in the cleaner lower guide 150. The cleaner upper guide 140 and the upper groove 141 are configured only on the front side in the insertion direction of the cleaning device 60, and have a dimensional relationship that eliminates interference with the cleaning device 60 when the cleaning device 60 is completely inserted. . The cleaner lower guide 150 and the lower groove 151 are formed in substantially the entire area along the longitudinal direction of the cleaning device 60 in the insertion direction.

  On the other hand, the cleaning device 60 includes an upper convex guide 77 on the upper surface, a lower convex guide 78 on the lower surface, and a handle 76 for latching the cleaning device 60 to the intermediate transfer body unit 30. The upward convex guide 77 and the downward convex guide 78 are formed in substantially the entire region along the longitudinal direction of the cleaning device 60 in the insertion direction. The insertion opening of the cleaning device 60 constituted by the cleaner upper guide 140 and the cleaner lower guide 150 is configured to have substantially the same shape as the cross-sectional shape of the cleaning device 60.

  The cleaning device 60 is inserted into the main body with the upper convex guide 77 aligned with the upper groove 141 and the lower convex guide 78 aligned with the lower groove 151, and is inserted while being restrained by this. During the insertion as shown in FIG. 10B, the cleaning device 60 cannot be operated in the direction other than the insertion direction by being restrained by the guide. As a result, the cleaning device 60 can be prevented from contacting the intermediate transfer belt 31 during insertion, and the intermediate transfer belt 31 and the cleaning blade 61 are not damaged.

  As shown in FIG. 10C, when the insertion of the cleaning device 60 is completed, the upper convex guide 77 comes out of the upper groove 141 and the upper restraint is released. When the cleaning device 60 is completely inserted, the screw input 67 engages with the coupling 160, and at the same time, the positioning member 71 is positioned on the two positioning shafts 223a and 223b installed on the connecting member 220. .

  Then, the handle 76 is operated as shown in FIG. 9B, and the cleaning device 60 is moved to the state shown in FIG. 9C around the axis S formed by the screw input 67 and the center of the discharge guide 72 shown in FIG. It can be rotated.

  Next, FIG. 1, FIG. 11 and FIG. 12 show the characteristic configuration of the present invention, 31 is an intermediate transfer belt, 33 is a tension roller, 38 is a tension roller shaft, 108 is a connecting member positioning shaft, 104 is a stopper, Reference numeral 200 denotes a pressure release lever that is a fixing member for fixing the tension roller, 202 denotes a lock part, 203 denotes a lock release part, 60 denotes a cleaning device, and 68 denotes an action part. 1, FIG. 11 and FIG. 12 are diagrams for explaining the front side of the tension roller 33, but the rear side has the same configuration.

  As shown in FIG. 11, the pressure release lever 200 prevents the detachment by fitting an oscillation center hole 201 to the tension roller shaft 38 and installing an E ring (not shown) at the shaft end of the tension roller shaft 37. As a result, the pressure release lever 200 is swingably attached about the tension roller shaft 38.

  Further, the distance L1 between the rocking center hole 201 of the pressure release lever 200 and the lock portion 202 is equal to the distance L2 between the tension roller shaft 38 and the connecting member positioning shaft 108 in a state where a predetermined tension is applied to the intermediate transfer belt 31. Configured to be short.

  Accordingly, the pressure release lever 200 is rotated counterclockwise in FIG. 11 about the tension roller shaft 38, and the lock portion 202 guided by the taper portion 204 is engaged with the connecting member positioning shaft 108, thereby tension. The roller shaft can be moved to the right in FIG. 11 against the force of the tension spring 107 to hold the intermediate transfer belt 31 in a state in which the tension of the intermediate transfer belt 31 is relaxed by a predetermined amount.

  By the way, in the image forming apparatus of the present invention, at the time of shipment, the cleaning device 60 and the process cartridge 10 are not packed in the image forming apparatus but shipped separately, and the intermediate transfer body unit 30 is mounted in the image forming apparatus. Shipped in. Therefore, the user needs to attach the process cartridge 10 and the cleaning device 60 when installing the image forming apparatus.

  Here, as shown in FIG. 1, the cleaning device 60 is provided with an action portion 68. This action part 68 abuts on the lock release part 203 which is a part of the pressure release lever 200 during the operation of latching the cleaning device 60. As a result, the pressure release lever 200 rotates about the swing center hole 201 and the contact between the connecting member positioning shaft 108 and the lock portion 202 is released. The tension roller receives the force of the tension spring 107 and moves to the left in FIG. 1, and a predetermined tension is applied to the intermediate transfer belt 31.

  When the lock is released, the pressure release lever 200 is held in a rotated state until it comes into contact with the stopper 104 provided in the roller support device 100 and does not fall off the intermediate transfer body unit 30. FIG. 1 is a diagram illustrating the front side of the tension roller 33, but the rear side has the same configuration.

  As described above, the user can easily and reliably apply the predetermined tension to the intermediate transfer belt 31 only by the operation of attaching the cleaning device 60 to the main body when the image forming apparatus main body is installed.

  On the other hand, the same applies to the replacement intermediate transfer body unit 30, and the tension of the intermediate transfer belt 31 is relaxed by a predetermined amount by the pressure release lever 200 at the time of shipment. Therefore, the user needs to release the lock by the pressure release lever 200 before use.

  As described above, the intermediate transfer body unit 30 separates the photosensitive drum 12 from the intermediate transfer belt 31 by lowering the lower side of FIG. It is the structure which can be made to do. Further, the intermediate transfer body unit 30 is configured to be detachable from the side surface of the image forming apparatus. Even with the intermediate transfer body unit 30 removed, the cleaning device 60 is fixed to the front of the connecting member 220 and the rear of the connecting member 220 '.

  Accordingly, as shown in FIG. 12, when the intermediate transfer body unit 30 in which the tension of the intermediate transfer belt 31 is loosened by the pressure release lever 200 is mounted from the side surface of the image forming apparatus, the connection member front 220 and the connection member rear 220 ′ are attached. The lock release portion 203 of the pressure release lever 200 abuts on the action portion 68 of the cleaning device 60 that is fixed. Then, the pressure release lever 200 rotates around the tension roller shaft 38 to release the engagement between the lock portion 202 and the connecting member positioning shaft 108, and a predetermined tension is applied to the intermediate transfer belt 31.

  As described above, when replacing the intermediate transfer body unit 30, the user can easily apply a predetermined tension to the intermediate transfer belt 31 only by the operation of mounting the intermediate transfer body unit 30 without performing any special operation.・ Can be implemented reliably.

(Example 2)
In the first embodiment, the cleaning device 60 is positioned and fixed to the intermediate transfer body unit 30 via the connecting members 220 and 220 ′. However, the present invention is not limited to this, and a configuration in which the connecting members 120 and 120 ′ are fixed to the intermediate transfer member unit 30 as shown in FIGS. 13 and 14 is also possible as a second embodiment.

  120 is a connecting member B, 121 ′ is a connecting member B, 121, 121 ′ are a CL latch shaft B, 122 is a first positioning elongated hole B, 123 is a CL positioning shaft B, 125 is a tension shaft fitting portion, Reference numeral 100 denotes a roller support device, 107 denotes a tension spring, 108 denotes a connecting member positioning shaft B, and 109 denotes a connecting member positioning shaft fitting portion.

  As shown in FIGS. 13 and 14, the connecting member front B 120 and the connecting member rear B 120 ′ are arranged at both ends of the tension roller shaft 38. The connecting members B120 and 121 ′ have the tip of the connecting member positioning shaft B108 in which the tension shaft fitting portion 125 is fitted to the end of the tension roller shaft 38 and the connecting member positioning elongated hole 124 is disposed in the roller support device 100. It is comprised so that it may fit in the connection member positioning shaft fitting part 109 provided in the part.

  When the connecting members B121 and 121 'are installed on the connecting member positioning shaft B108, the connecting member positioning shaft fitting portion 109 is configured to slightly protrude from the surface of the connecting members B121 and 121'. Therefore, even if the connecting members B121 and 121 'are fixed by the connecting member positioning shaft B108 with screws, the connecting members B121 and 121' are not completely fixed.

  Accordingly, the connecting members B121 and 121 'are configured to be able to freely move in the horizontal direction in FIG. 14 in conjunction with the tension roller 33. Further, CL latch shafts B121 and 121 'for positioning the cleaning device 60 are arranged on the connecting members B120 and 121'. The positions of the CL latch shafts B121 and 121 'are accurately determined with respect to the axis T of the tension roller shaft 38.

  Thus, even when the position of the tension roller 33 moves along the tension oblong hole 102, the axis T of the tension roller shaft 38 and the line T ′ connecting the CL latch shafts 121 and 121 ′ are always kept parallel. Be drunk.

  Since the positioning and fixing configuration of the cleaning device 60 to the intermediate transfer body unit 30 and the arrangement configuration of the pressure release lever 200 are the same as those in the first embodiment, the description thereof is omitted.

FIG. 3 is a diagram illustrating a configuration for applying tension to an intermediate transfer belt according to the first exemplary embodiment of the present invention. 1 is a diagram illustrating an image forming apparatus according to a first embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of an intermediate transfer body unit and a cleaning device according to the first embodiment of the present invention. FIG. 3 is a perspective view illustrating a positioning configuration of the cleaning device with respect to the intermediate transfer body unit according to the first embodiment of the present invention. It is a figure explaining the positioning structure to the tension roller of the connection member based on 1st Example of this invention. It is a figure explaining the positioning structure to the tension roller of the connection member based on 1st Example of this invention. FIG. 3 is a diagram illustrating a configuration for applying tension to an intermediate transfer belt according to the first exemplary embodiment of the present invention. It is a figure explaining the positioning and fixing structure of the cleaning apparatus after the connection member based on 1st Example of this invention. It is a figure explaining the positioning and fixing structure of the cleaning device in front of the connecting member according to the first embodiment of the present invention. It is a figure explaining the insertion guide of the cleaning apparatus based on 1st Example of this invention. FIG. 3 is a diagram illustrating a configuration for relaxing the tension of the intermediate transfer belt according to the first exemplary embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration for applying tension to an intermediate transfer belt according to the first exemplary embodiment of the present invention. FIG. 6 is a perspective view illustrating the configuration of an intermediate transfer body unit and a cleaning device according to a second embodiment of the present invention. It is a figure explaining the positioning structure to the tension roller of the connection member based on 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 30 Intermediate transfer body unit 31 Intermediate transfer belt 33 Tension roller 38 Tension roller shaft 60 Cleaning device 68 Action part 100 Roller support device 108 Connection member positioning shaft 107 Tension spring 200 Pressure release lever 202 Lock part 203 Lock release part 220 Before connection member 220 '' After connecting member

Claims (6)

An endless belt body, a plurality of stretching members that stretch the belt body, and one of the plurality of stretching members, and the belt body in a direction from the inside to the outside of the belt body A belt unit comprising: a tension roller biased by a biasing means for applying a pressing force; and a regulating means for regulating the position of the shaft of the tension roller biased by the biasing means; and a belt A cleaning device including a cleaning blade that contacts an outer surface of the belt body for cleaning toner on the body, and a connecting member that connects the belt unit and the cleaning device, and the belt unit is attached to the main body of the device. It is possible to release the application of pressure to the belt body by the tension roller by the restricting means. In an image forming apparatus,
A connecting member for connecting the belt unit and the cleaning device, the cleaning device having an action part for moving the restricting means, and the restricting means being rotatable about an axis of the tension roller; The other end has a restricting portion that restricts the position of the shaft of the tension roller.
When the cleaning device comes into contact with the belt body at a predetermined position by the connecting member, the action portion comes into contact with one end of the restriction means, and the restriction means rotates. When the restriction on the shaft of the tension roller by the other end of the restricting means is released, the tension roller can be applied to the belt body from the state where the application of the pressure to the belt body is released by the restriction member. An image forming apparatus that shifts to a state in which the image is given . The cleaning device is detachable from an apparatus main body, and the attaching / detaching direction of the cleaning apparatus with respect to the apparatus main body is orthogonal to the attaching / detaching direction of the belt unit with respect to the apparatus main body. The image forming apparatus according to 1. In the apparatus main body, withdrawn from a state in which the cleaning device is arranged at a predetermined position with respect to the tension roller, without changing the arrangement in the apparatus main body of the cleaning apparatus, only the belt unit from the main body The image forming apparatus according to claim 1, wherein the image forming apparatus can perform the operation. In the apparatus body from a state in which the cleaning device is arranged at a predetermined position with respect to the tension roller, extracting only the belt unit from the apparatus main body, only the re belt unit, and put into the apparatus main assembly, the cleaning The image forming apparatus according to claim 1, wherein the apparatus is disposed at a predetermined position with respect to the tension roller . 5. The apparatus according to claim 1, further comprising an image carrier that carries a toner image, wherein the belt body is an intermediate transfer body on which a toner image is transferred from the image carrier. Image forming apparatus. The distance from the rotating shaft of the restricting means to one end in contact with the action portion is shorter than the distance from the rotating shaft of the restricting means to the other end of the restricting means. 6. The image forming apparatus according to any one of items 5.

Images