JP5078503B2 - Belt conveying apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to a belt conveying device that rotates an endless belt while being stretched by a plurality of stretching members, and more particularly to a belt conveying device used in an image forming apparatus using an electrophotographic system.

  2. Description of the Related Art Conventionally, some image forming apparatuses such as printers and copiers using an electrophotographic system use a belt conveyance device that rotates an endless belt while being stretched by a plurality of stretching rollers. In such a belt conveyance device, when the belt is rotated, there is a problem that the belt meanders in the width direction, for example, the belt is shifted to one side in the width direction orthogonal to the rotation direction.

  As a technique for solving such a problem, Patent Document 1 discloses a device for controlling the meandering of the belt described above. This belt meandering control device is provided with a roller that is separate from a driving roller for running the belt, and swings the swinging roller in either direction. This is a device for controlling the meandering of the belt. Specifically, the spring clutch transmits or does not transmit the driving force from the driving source by the operating member that swings according to the meandering of the belt, and the cam is rotated by the driving force to support the swinging roller. The swing lever is swingable in either direction. With this configuration, in response to the deviation of the belt in the width direction, the swing roller is swung in either direction to control the meandering of the belt.

Japanese Patent No. 2788683

  However, in the configuration of the conventional belt meandering control device, the swing roller swings only a certain amount in response to the shift in the belt width direction regardless of the amount of movement of the belt in the width direction. Therefore, for example, when the amount of movement in the width direction of the belt becomes larger than the initial use due to wear of the roller due to long-term use, it takes time to correct the deviation in the width direction of the belt, In some cases, it may not be possible to make corrections.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a belt conveyance device that can efficiently and reliably correct the deviation of the belt in accordance with the deviation of the belt in the width direction.

  A typical configuration of the present invention for achieving the above object is that an endless belt is stretched by a first tension member and a second tension member that can be inclined with respect to the first tension member. A belt conveying device that rotates and moves while being in contact with the end in the width direction orthogonal to the rotational movement direction of the belt, and that moves following the movement of the belt in the width direction; The second tension member is movably supported, the detection member is engageable, and the second tension member is tilted with respect to the first tension member by a driving force from the engaged detection member. And an angle setting mechanism for changing an inclination angle of the second stretching member with respect to the first stretching member in accordance with a movement amount of the detection member. .

  According to the present invention, the second tension member is changed to an inclination angle corresponding to the amount of movement of the moving member (that is, the shift in the belt width direction). Therefore, the movement of the belt can be corrected efficiently and reliably according to the amount of movement of the belt in the width direction.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. Therefore, unless specifically stated otherwise, the scope of the present invention is not intended to be limited thereto.

[First Embodiment]
First, a schematic configuration of an image forming apparatus having a belt conveyance device will be described. FIG. 13 is a schematic cross-sectional view illustrating an example of an image forming apparatus having a belt conveyance device.

  The image forming apparatus shown in FIG. 13 is an image forming apparatus that forms a toner image on a recording material P, and has a recording material conveyance unit 100 as a belt conveyance device that carries the recording material P and conveys it in the vertical direction. ing. The recording material transport unit 100 is detachably provided to the image forming apparatus main body. Four image forming units of different colors are arranged in parallel in the vertical direction at a position facing the recording material transport unit 100. Here, four image forming units of yellow (hereinafter referred to as Y), magenta (hereinafter referred to as M), cyan (hereinafter referred to as C), and black (hereinafter referred to as K) are illustrated. Each image forming unit is similarly configured. In each image forming unit, 36 is a laser scanner, and 34 is a process cartridge. The process cartridge 34 includes a photosensitive drum 31, a charging roller 32 and a developing unit 33 as process means acting on the photosensitive drum 31, and is detachable from the image forming apparatus main body.

  A transfer roller 35 is disposed at a position opposed to the photosensitive drum 31 of each image forming unit via the endless belt 1 of the recording material transport unit 100. In addition, a feeding unit 41 and an MP feeding unit 42 for feeding recording materials one by one are arranged at the lower part of the image forming apparatus. Further, a fixing unit 38 is disposed on the upper part of the image forming apparatus.

  In each image forming unit, the photosensitive drum 31 uniformly charged by the charging roller 32 is irradiated with laser light 37 from the laser scanner 36 to form a latent image, and the latent image is visualized as a toner image by the developing device 33. The Thereafter, the recording material P selectively fed from the feeding units 41 and 42 is transported onto the endless belt 1 suspended by rollers in the recording material transport unit 100, and is carried and transported by the belt 1. Is done. The recording material P carried and conveyed by the belt 1 is sequentially sandwiched between the transfer roller 35 and the photosensitive drum 31 forming the transfer portion T, and the toner image on each photosensitive drum 31 is transferred onto the recording material P in an overlapping manner. The Subsequently, the toner image on the recording material is pressurized and heated by the fixing unit 38, fixed on the recording material, and then discharged to the discharge tray 40 by the discharge roller 39.

  The process cartridge is replaced by removing the recording material transport unit 100 from the main body of the image forming apparatus. As will be described later, since the recording material conveyance unit 100 independently corrects the deviation of the belt in the width direction regardless of the attachment state, the change in the attachment state when the cartridge is attached / detached changes the endless belt of the recording material conveyance unit 100. 1 can be used stably without affecting the lifetime.

  Next, the recording material conveyance unit as the belt conveyance device will be described in detail. FIG. 1 is an external view of a recording material transport unit. FIG. 2 is a view showing a state in which the side plate 9A is removed so that the inside of the recording material transport unit can be seen.

  As shown in FIGS. 1 and 2, the recording material conveyance unit 100 includes a conveyance transfer belt 1 as an endless belt. The belt 1 is stretched by a driven roller 3 and a tension roller 4 as a first stretching member, and a driving roller 2 as a second stretching member that can be inclined with respect to the driven roller 3. The driving roller 2 is rotationally driven, so that the belt 1 is rotationally moved.

  The tension roller 4 is held so as to be movable in the direction of arrow T in FIG. 2 and is urged by a tension roller urging spring 5 to apply tension to the belt 1.

  Reference numeral 6 denotes a bearing of the driving roller 2, 7 denotes a bearing of the driven roller 3, and 8 denotes a bearing of the tension roller 4. Reference numerals 9A and 9B denote side plates, which hold the bearings 6, 7 and 8 of the three rollers.

  The bearing on the side plate 9B side of the driving roller 2 is held so as not to move, but the bearing on the side plate 9A side of the driving roller 2 is held movably in the direction of arrow AA or BB. Thus, the driving roller 2 is held in the axial direction so as to be parallel to the driven roller 3 or tilted so that the belt 32 is twisted.

  As shown in FIG. 2, the recording material conveyance unit 100 includes an automatic alignment mechanism 10 that automatically corrects the deviation of the belt 1 in the width direction. Hereinafter, the self-aligning mechanism 10 will be described in detail with reference to FIGS.

  The self-aligning mechanism 10 is an angle setting mechanism that includes a detector 30 and a mover 21 described below, and changes the inclination angle of the drive roller 2 with respect to the driven roller 3 in accordance with the amount of movement of the detector 30. As shown in FIGS. 4, 6, and 7, the detector 30 has a detection roller 25 that contacts the end in the width direction perpendicular to the rotational movement direction of the belt 1 and detects the belt end surface. The detector 30 is a detection member which is provided so as to be able to swing around the fulcrum 26 and moves following the movement of the detection roller 25 in contact with the belt end surface in the width direction of the belt 1. The detector 30 is urged in the direction of arrow Fb around the fulcrum 26 so that the detection roller 25 always contacts the end face of the belt 1. Further, the detector 30 is provided with a drive gear 23 having a fulcrum 26 as a center and a drive output gear 24 that is rotationally driven by the drive gear 23. Here, as shown in FIGS. 4, 6, and 7, the configuration in which the drive gear 23 is driven by the motor M as a drive source is illustrated. The drive force of the drive gear is the drive of the drive roller 2. It may be a driving force from the source or an input from the belt 1 being conveyed.

  As shown in FIGS. 3 and 5, a screw portion 20 as a drive output portion is provided on the same axis as the drive output gear 24. The screw portion 20 has a right screw portion 20A and a left screw portion 20B as drive output portions that can be selectively engaged with a drive input portion of a moving element 21 described later, and in the same direction as the drive output gear 24. Rotate.

  As described above, the movable element 21 is engaged with the shaft of the drive roller 2 supported so as to be movable in the direction of the arrow AA or BB on the side plate 9A side. The mover 21 is provided so as to be rotatable about a fulcrum 22, and the drive roller 2 is moved in the direction of arrow AA or BB by the rotation of the mover 21 around the fulcrum 22. Here, the arrow AA direction is a first direction in which the belt 1 is moved in one width direction, and the arrow BB direction is a second direction in which the belt 1 is moved in the other width direction.

  The mover 21 has a right female screw portion 21A as a first drive input portion to which the screw portion 20 of the detector 30 can be engaged, and a left female screw portion 21B as a second drive input portion. The right female screw portion 21A has a right screw female screw, and the left female screw portion 21B has a left female screw. Due to the driving force from the screw portion 20 selectively engaged with the female screw portions 21A and 21B, the movable element 21 is rotationally moved around the fulcrum 22 in the direction of arrow AA or BB.

  Thereby, the moving element 21 can change the inclination angle of the driving roller 2 with respect to the driven roller 3 according to the amount of movement of the detection roller 25.

  Here, an operation of correcting the shift of the belt 1 in the width direction by the self-aligning mechanism 10 will be described.

  First, with reference to FIG. 3 and FIG. 4, a correction operation when the belt 1 moves in the direction of arrow R with respect to the ideal position 1i (here, the position 1r is illustrated) will be described.

  When the driving roller 2 is driven to rotate, the belt 1 rotates in the direction of arrow D. At this time, no matter how accurately the accuracy and parallelism of the rollers 2, 3 and 4 and the belt 1 are managed, the belt 1 tends to be in the direction of either the arrow L or R. When the belt 1 approaches the ideal position 1i in the direction of the arrow R, it operates as follows.

  As shown in FIG. 4, when the belt 1 approaches the other side in the width direction (arrow R direction), the end surface of the belt 1 is detected by the detection roller 25, and the detector 30 rotates counterclockwise around the fulcrum 26. To do. When the detector 30 rotates counterclockwise, the drive output gear 24 connected to the drive gear 23 moves toward the right female screw portion 21A around the fulcrum 26, and the right screw portion of the screw portion 20 shown in FIG. 20A engages with the right female screw portion 21A of the movable element 21. The drive output gear 24 is rotated in the clockwise direction by the drive gear 23 that rotates counterclockwise around the fulcrum 26 by the driving force from the motor M. Then, the clockwise rotation of the drive output gear 24 is output from the right screw portion 20A rotating in the same direction to the right female screw portion 21A, and the mover 21 rotates counterclockwise around the fulcrum 22. The drive roller 2 is moved in the direction of arrow AA (first direction). When the driving roller 2 is moved in the direction of the arrow AA in this way, a force acting in the direction of the arrow L (one in the width direction) shown in FIG. 4 acts on the belt 1, that is, the belt 1 tends to be shifted in the direction of the arrow R. The inclination angle of the drive roller 2 is adjusted in the direction to cancel the. In other words, the drive roller 2 has an arrow AA direction (first direction) with respect to the driven roller 3 so that the belt 1 approaching the other in the width direction (arrow R direction) is moved toward the width direction one (arrow L direction). Tilted to. The inclination angle of the driving roller 2 with respect to the driven roller 3 at this time is an amount corresponding to the amount of movement of the detection roller 25 that has moved following the movement of the belt 1 in the other width direction.

  Similarly, with reference to FIGS. 5 and 6, the correction operation when the belt 1 is shifted in the direction of the arrow L with respect to the ideal position 1i (here, the position 1l is illustrated) will be described.

  As shown in FIG. 6, when the belt 1 approaches one side in the width direction (arrow L direction), the end surface of the belt 1 is detected by the detection roller 25, and the detector 30 rotates clockwise about the fulcrum 26. . When the detector 30 rotates in the clockwise direction, the drive output gear 24 connected to the drive gear 23 moves toward the left female screw portion 21B around the fulcrum 26, and the left screw portion 20B of the screw portion 20 shown in FIG. Engages with the left female screw portion 21 </ b> B of the mover 21. The drive output gear 24 is rotated in the clockwise direction by the drive gear 23 that rotates counterclockwise around the fulcrum 26 by the driving force from the motor M. Then, the clockwise rotation of the drive output gear 24 is output from the left screw portion 20B rotating in the same direction to the left female screw portion 21B, and the movable element 21 rotates clockwise around the fulcrum 22; The drive roller 2 is moved in the arrow BB direction (second direction). When the drive roller 2 is moved in the direction of the arrow BB in this way, a force acting in the direction of the arrow R (the other in the width direction) shown in FIG. 6 acts on the belt 1, that is, the belt 1 tends to be shifted in the direction of the arrow L. The inclination angle of the drive roller 2 is adjusted in the direction to cancel the. In other words, the driving roller 2 moves in the direction of arrow AA (second direction) with respect to the driven roller 3 so that the belt 1 approaching in the width direction (arrow L direction) is moved toward the other width direction (arrow R direction). Tilted. The inclination angle of the driving roller 2 with respect to the driven roller 3 at this time corresponds to the amount of movement of the detection roller 25 that has moved following the movement of the belt 1 in one width direction.

  As described above, even if the belt 1 is deviated from the ideal position in any direction in the width direction, the inclination angle of the driving roller 2 is adjusted in a direction to cancel the belt 1. Then, the belt 1 travels in a state where the deviation in the width direction is controlled. As a result, as shown in FIG. 7, the screw part 20 (drive output gear 24) of the detector 30 has any female screw part 21A. , 21B, the equilibrium state is reached.

  As described above, according to the present embodiment, the driving roller 2 is changed to an inclination angle corresponding to the amount of movement of the detector 30 (that is, the shift in the width direction of the belt 1). Therefore, the shift of the belt 1 can be corrected efficiently and reliably according to the amount of movement of the belt 1 in the width direction.

[Second Embodiment]
Another example of the self-aligning mechanism included in the recording material conveyance unit 100 as the belt conveyance device will be described. Since the configurations of the belt conveyance device and the image forming apparatus excluding the automatic alignment mechanism are the same as those in the above-described embodiment, the description thereof is omitted here. Moreover, the same code | symbol is attached | subjected to the member which has an equivalent function. Hereinafter, the self-aligning mechanism will be described in detail with reference to FIGS.

  The self-aligning mechanism has a detector 30, a moving element 51, and a moving element driving unit 50 described below, and an angle for changing the inclination angle of the driving roller 2 with respect to the driven roller 3 according to the amount of movement of the detecting element 30. It is a setting mechanism. As shown in FIGS. 9, 11, and 12, the detector 30 includes a detection roller 25 that detects a belt end surface by contacting a width direction end portion orthogonal to the rotational movement direction of the belt 1. The detection roller 25 is a detection member that is provided so as to be swingable about a fulcrum 26 and moves following the movement of the detection roller 25 in contact with the belt end surface in the width direction of the belt 1. The detector 30 is urged in the direction of arrow Fb around the fulcrum 26 so that the detection roller 25 always contacts the end face of the belt 1. Further, the detector 30 is provided with a drive gear 23 having a fulcrum 26 as a center and a drive output friction wheel 54 that is rotationally driven by the drive gear 23. The drive output friction wheel 24 is constituted by a friction conducting portion made of EPDM or the like. Here, as shown in FIGS. 9, 11, and 12, a configuration in which the drive gear 23 is driven by the motor M as a drive source is illustrated. The drive force of the drive gear is the drive of the drive roller 2. It may be a driving force from the source or an input from the belt 1 being conveyed.

  As described above, the movable element 51 is engaged with the shaft of the driving roller 2 supported so as to be movable in the direction of the arrow AA or BB on the side plate 9A side. The mover 51 is provided so as to be rotatable around a fulcrum 52, and the drive roller 2 is moved in the direction of arrow AA or BB by the rotation of the mover 51 around the fulcrum 52. Here, the arrow AA direction is a first direction in which the belt 1 is moved in one width direction, and the arrow BB direction is a second direction in which the belt 1 is moved in the other width direction. The mover 51 has a nut portion 51C coupled to a screw portion 50D of the mover drive unit 50 described later.

  The moving element drive unit 50 has an outer sliding part 50A as a first driving input part and an inner sliding part 50B as a second driving input part with which the driving output friction wheel 54 of the detector 30 can be engaged. Yes. Furthermore, the moving element drive unit 50 has a screw part 50D on the same axis, and the screw part 50D is connected to the nut part 51C of the moving element 51. The moving element 51 is rotationally moved in the direction of the arrow AA or BB about the fulcrum 52 by the driving force from the moving element driving unit 50 selectively engaged with the sliding parts 50A and 50B.

  Thereby, the moving element 51 can change the inclination angle of the driving roller 2 with respect to the driven roller 3 according to the movement amount of the detection roller 25.

  Here, an operation of correcting the shift of the belt 1 in the width direction by the self-aligning mechanism will be described.

  First, with reference to FIGS. 8 and 9, the correction operation when the belt 1 is shifted in the arrow R direction with respect to the ideal position 1i (here, the position 1r is illustrated) will be described.

  When the driving roller 2 is driven to rotate, the belt 1 rotates in the direction of arrow D. At this time, no matter how accurately the accuracy and parallelism of the rollers 2, 3 and 4 and the belt 1 are managed, the belt 1 tends to be in the direction of either the arrow L or R. When the belt 1 approaches the ideal position 1i in the direction of the arrow R, it operates as follows.

  As shown in FIG. 9, when the belt 1 approaches the other side in the width direction (arrow R direction), the other surface of the belt 1 is detected by the detection roller 25, and the detector 30 is counterclockwise about the fulcrum 26. Rotate. When the detector 30 rotates counterclockwise, the drive output friction wheel 54 connected to the drive gear 23 comes into contact with the outer sliding portion 50 </ b> A of the mover drive unit 50. The drive output friction wheel 54 is rotated in the clockwise direction by the drive gear 23 that rotates counterclockwise around the fulcrum 26 by the driving force from the motor M. This rotation is output from the drive output friction wheel 54 to the outer sliding portion 50A, and further output from the screw portion 50D to the nut portion 51C. 2 is moved in the direction of arrow AA (first direction). When the driving roller 2 is moved in the direction of the arrow AA in this way, a force acting in the direction of the arrow L (one side in the width direction) shown in FIG. The inclination angle of the drive roller 2 is adjusted in the direction to cancel the. In other words, the drive roller 2 has an arrow AA direction (first direction) with respect to the driven roller 3 so that the belt 1 approaching the other in the width direction (arrow R direction) is moved toward the width direction one (arrow L direction). Tilted to. The inclination angle of the driving roller 2 with respect to the driven roller 3 at this time is an amount corresponding to the amount of movement of the detection roller 25 that has moved following the movement of the belt 1 in the other width direction.

  Similarly, with reference to FIGS. 10 and 11, the correction operation when the belt 1 moves in the direction of the arrow L with respect to the ideal position 1 i (here, the position 1 l is illustrated) will be described.

  As shown in FIG. 11, when the belt 1 approaches one side in the width direction (arrow L direction), the end face of the belt 1 is detected by the detection roller 25, and the detector 30 rotates counterclockwise around the fulcrum 26. To do. When the detector 30 rotates in the clockwise direction, the drive output friction wheel 54 connected to the drive gear 23 comes into contact with the inner sliding portion 50 </ b> B of the moving member driving unit 50. The drive output friction wheel 24 is rotated in the clockwise direction by the drive gear 23 that rotates counterclockwise around the fulcrum 26 by the driving force from the motor M. This rotation is output from the drive output friction wheel 54 to the inner sliding portion 50B, and further output from the screw portion 50D to the nut portion 51C. The moving element 51 rotates clockwise around the fulcrum 52, and the driving roller 2 Is moved in the direction of arrow BB (second direction). When the driving roller 2 is moved in the direction of the arrow BB in this way, a force acting in the direction of the arrow R (the other in the width direction) shown in FIG. 11 acts on the belt 1, that is, the belt 1 tends to be shifted in the direction of the arrow L. The inclination angle of the drive roller 2 is adjusted in the direction to cancel the. In other words, the drive roller 2 moves in the direction of the arrow BB (second direction) relative to the driven roller 3 so that the belt 1 approaching in the width direction (arrow L direction) is moved toward the other width direction (arrow R direction). Tilted to. The inclination angle of the driving roller 2 with respect to the driven roller 3 at this time corresponds to the amount of movement of the detection roller 25 that has moved following the movement of the belt 1 in one width direction.

  As described above, even if the belt 1 is deviated from the ideal position in any direction in the width direction, the inclination angle of the driving roller 2 is adjusted in a direction to cancel the belt 1. The belt 1 travels in a state where the deviation in the width direction is controlled. As a result, as shown in FIG. 12, the drive output friction wheel 24 of the detector 30 contacts any of the sliding portions 20A and 20B. The equilibrium state is reached in the region that is not.

  As described above, according to the present embodiment, the driving roller 2 is changed to an inclination angle corresponding to the amount of movement of the detector 30 (that is, the shift in the width direction of the belt 1). Therefore, the shift of the belt 1 can be corrected efficiently and reliably according to the amount of movement of the belt 1 in the width direction.

[Other Embodiments]
In the above-described embodiment, the belt conveyance device that carries and conveys the recording material is exemplified as the belt conveyance device, but is not limited thereto. For example, a belt conveyance device having an intermediate transfer belt for carrying and conveying a toner image or a heating device having a belt-like heating film for heating a toner image on the recording material while conveying the recording material. May be. Even if the present invention is applied to such a belt conveyance device, the same effect can be obtained.

  In the above-described embodiment, four image forming units are used. However, the number of used units is not limited, and may be set as appropriate.

  In the above-described embodiment, as a process cartridge that is detachable from the main body of the image forming apparatus, a process cartridge that integrally includes a photosensitive drum and a charging unit, a developing unit, and a cleaning unit as process units that act on the photosensitive drum. Illustrated. The process cartridge is not limited to this, and may be a process cartridge integrally including any one of a charging unit, a developing unit, and a cleaning unit in addition to the photosensitive drum.

  Further, in the above-described embodiment, the configuration in which the process cartridge including the photosensitive drum is detachable from the image forming apparatus main body is illustrated, but the present invention is not limited to this. For example, it may be an image forming apparatus in which each constituent member is incorporated, or an image forming apparatus in which each constituent member is detachable. The same applies by applying the present invention to the belt conveying device in these image forming apparatuses. An effect can be obtained.

  In the above-described embodiments, the printer is exemplified as the image forming apparatus. However, the present invention is not limited to this, and other image forming apparatuses such as a copying machine and a facsimile machine, or a combination of these functions. Other image forming apparatuses such as multifunction peripherals may also be used. The same effect can be obtained by applying the present invention to the belt conveying device in these image forming apparatuses.

External perspective view of recording material transport unit Internal perspective view of recording material transport unit Side view of automatic alignment mechanism in first embodiment Front view of the self-aligning mechanism (when the belt is closer to the right than the ideal position) in the first embodiment Side view of automatic alignment mechanism in first embodiment Front view of the self-aligning mechanism (when the belt is closer to the left than the ideal position) in the first embodiment Front view of self-aligning mechanism (ideal position) in the first embodiment Side view of self-aligning mechanism in second embodiment Front view of the self-aligning mechanism (when the belt moves to the right from the ideal position) in the second embodiment Side view of self-aligning mechanism in second embodiment Front view of the self-aligning mechanism (when the belt moves to the left of the ideal position) in the second embodiment Front view of self-aligning mechanism (ideal position) in the second embodiment Schematic sectional view of an image forming apparatus having a belt conveying device

Explanation of symbols

P ... Recording material 1 ... Belt 2 ... Drive roller 3 ... Drive roller 4 ... Tension roller 5 ... Tension roller biasing springs 6, 7, 8 ... Bearings 9A, 9B ... Side plate 10 ... Self-aligning mechanism 20 ... Screw part 20A ... Right screw portion 20B ... Left screw portion 21 ... Movement element 21A ... Right female screw portion 21B ... Left female screw portion 22 ... Support point 23 ... Drive gear 24 ... Drive output gear 25 ... Detection roller 26 ... Support point 30 ... Detector 50 ... Movement Slave drive part 50A ... Outer sliding part 50B ... Inner sliding part 50D ... Screw part 51 ... Mover 51C ... Nut part 52 ... Supporting point 54 ... Drive output friction wheel 100 ... Recording material transport unit

Claims (6)

A belt conveying device that rotates and rotates an endless belt by a first tension member and a second tension member that can be inclined with respect to the first tension member,
A detection member that always contacts a width direction end perpendicular to the rotational movement direction of the belt and moves following the movement of the belt in the width direction;
The second tension member is movably supported, the detection member is engageable, and the second tension member is moved relative to the first tension member by a driving force from the engaged detection member. A moving member that moves so as to be inclined,
A belt conveying device comprising an angle setting mechanism for changing an inclination angle of the second stretching member with respect to the first stretching member in accordance with a movement amount of the detection member. The moving member includes a first drive input portion for inputting a driving force for inclining the second stretching member in a first direction for moving the belt in one width direction, and a first drive input portion for moving the belt in the other width direction. A second drive input unit for inputting a drive force for inclining the second tension member in the direction of 2;
The detection member selectively engages with any one of the drive input portions of the moving member by movement following the movement of the belt in the width direction, and outputs the drive force to the engaged drive input portion. The belt conveyance device according to claim 1, further comprising an output unit.   The belt conveyance device according to claim 2, wherein a region where the drive output portion of the detection member does not engage with any drive input portion of the moving member is provided.   An image forming apparatus for forming a toner image on a recording material, comprising the belt conveyance device according to any one of claims 1 to 3 as a belt conveyance device for carrying and conveying the toner image. An image forming apparatus.   An image forming apparatus for forming a toner image on a recording material, comprising the belt conveying device according to claim 1 as a belt conveying device for carrying and conveying the recording material. An image forming apparatus.   4. The belt according to claim 1, wherein the image forming apparatus forms a toner image on a recording material, and the heating device heats the toner image on the recording material while conveying the recording material. 5. An image forming apparatus comprising a conveying device.

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