JP2009086463A - Endless member rotation drive apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endless member rotation drive apparatus correcting deviation of the endless member in a simple and inexpensive structure. <P>SOLUTION: The endless member rotation drive apparatus includes: an endless member (B) that rotates by receiving drive force; a drive support member that supports and drives the endless member (B); a rotatable support member (Rj) that supports the endless member (B) and is rotated along with the rotation of the endless member (B); a supporting body (1) for supporting the rotatable support member (Rj) to be able to be moved in the shaft (Rj1) direction of the rotatable support member (Rj) and also able to be rocked in the direction intersecting the shaft (Rj1) direction, elastic members (18 and 19) whose outer shapes are varied based on the movement of the rotatable support member (Rj) in the shaft (Rj1) direction along with the deviation of the endless member (B). By having the outer shapes of the elastic members (18, 19) varied, the rotatable support member (Rj) is rocked in the direction for correcting the deviation in the endless member (B). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an endless member rotation driving device and an image forming apparatus.

As techniques related to a conventional image forming apparatus including an endless member, techniques described in Patent Documents 1 to 5 below are known.
In Patent Document 1 (Japanese Patent Laid-Open No. 4-121337), a meandering detection member having a tapered surface 11a whose outer shape increases toward the outer side at the axial end of the third roller member 3 that supports the photosensitive belt 4. 11 is arranged, and when the meandering occurs on the photosensitive belt 4, a technique for detecting the meandering is described by the photosensitive belt 4 riding on the meandering detection member 11 due to the meandering displacement. In the technique described in Patent Document 1, when the photosensitive belt 4 rides on the meandering detection member 11 and a rotational torque acts on the meandering detection member 11, the meandering detection member 11 rotates and the string connected to the meandering detection member 11. As the member 13 is wound up, the position of the shaft of the third roller member 3 is displaced to cancel the meandering. That is, a configuration is described in which, when the belt rides on a meandering detection member having a tapered surface and rotates, the axis is inclined in a direction in which meandering is detected and the deviation is corrected.

  Patent Document 2 (Japanese Patent Application Laid-Open No. 2002-173246) discloses a control roller 6 for preventing meandering of the transfer conveyance belt 1 and a movable end 6a that can move one end in the axial direction in a direction perpendicular to the axis. , A tension coil spring 28 that moves the movable end 6a so that the transfer conveyance belt 1 is displaced toward the movable end 6a side, and a tapered detection ring that is supported by the shaft member 20 of the control roller 6 and whose outer shape increases toward the outside. 29 and a pinion 30 that is disposed coaxially with the detection ring 29 and meshes with the rack 31. When the transfer conveyance belt 1 is offset and rides on the detection ring 29 and the detection ring 29 rotates, the pinion 30 is described. The movable end 6a is moved by the rack 31 in a direction in which the movable end is pulled back against the biasing force of the tension coil spring 28 and the transfer conveying belt 1 is displaced. It is. That is, a configuration is described in which when the belt rides on a tapered detection ring and rotates, the shaft is inclined in a direction in which the deviation is detected and corrected.

In Patent Document 3 (Japanese Patent Application Laid-Open No. 2001-80782), bearings 15a and 15b at both ends of a deviation correction roller 9e that supports an endless belt 9a are moved by support blocks 17a and 17b via links 16a and 16b. When the endless belt 9a is supported in a possible state and a force is generated that the endless belt 9a is offset, the ribs 19a and 19b provided on the back surface of the endless belt 9a transmit the force to the correction roller 9e and the links 16a and 16b are inclined. Thus, a technique is described in which the deviation correction roller 9e is inclined to eliminate the deviation.
In Patent Document 4 (Japanese Patent Application Laid-Open No. 4-317936), both ends of the shift correction roller 6 are movably supported via the inclined links 17a and 17b, and when the photosensitive belt 1 is inclined, the inclined links 17a, A technique is described in which 17b is inclined and the deviation correction roller 6 is inclined in a direction for correcting the deviation of the photosensitive belt 1.

  In Patent Document 5 (Japanese Patent Laid-Open No. 2006-162659), a pulley 57 in which a bead (rib) 58 of the transfer belt 51 comes into contact with the end of the idle roller 53 is rotatably supported. In the configuration in which the tiltable roller tilt lever 64 that supports and contacts the pulley 57 is provided, when the transfer belt 51 is displaced, the pulley 57 is pushed by the bead (rib) 58 and the contact roller tilt lever 64 tilts. Thus, a technique is described in which the idle roller 53 is inclined in a direction to cancel the deviation of the transfer belt 51.

JP-A-4-121337 (4th page, lower left column, line 10 to 5th page, lower left column, last line, FIGS. 1 to 3) JP 2002-173246 A (“0033” to “0037”, FIGS. 2 to 6) JP 2001-80782 ("0039" to "0062", FIGS. 1 to 3) JP-A-4-317936 ("0011" to "0013", FIGS. 2 and 3) JP 2006-162659 A ("0022" to "0045", FIGS. 3 to 13)

  This invention makes it a technical subject to correct | amend the offset of an endless member with a simple and cheap structure compared with the case where it does not have the structure of this invention.

In order to solve the technical problem, an endless member rotation driving device according to claim 1,
An endless member that is rotated by receiving a driving force and is endless in a planar shape on the front and back sides,
A drive support member for supporting and driving the endless member;
A rotation support member that supports the endless member and rotates with rotation of the endless member;
A support that rotatably supports the rotation support member and supports the rotation support member so as to be movable in an axial direction of the rotation support member and swingable in a direction intersecting the axial direction;
An elastic member that is elastically deformed by movement in the axial direction of the rotation support member along with the deviation of the endless member and changes in outer shape in a direction intersecting the axial direction,
The rotation support member is swung in a direction in which the elastic member is changed in outer shape to correct a deviation of the endless member.

In order to solve the technical problem, an endless member rotation driving device according to claim 2,
An endless member that is rotated by receiving a driving force and is endless in a planar shape on the front and back sides,
A drive support member for supporting and driving the endless member;
A rotation support member that supports the endless member and rotates with rotation of the endless member;
A support that rotatably supports the drive support member and the rotation support member;
When the endless member is rotated, the endless member is supported so as to be movable in the axial direction with respect to the support as the endless member moves in the axial direction of the rotation support member. The rotation support member supported so as to be swingable in a direction intersecting the axial direction,
An elastic member that is elastically deformed by movement of the rotation support member in the axial direction and changes in outer shape in a direction intersecting the axial direction;
A position restricting portion for restricting the position of the rotation support member with respect to the direction intersecting with the axial direction and restricting the position of the elastic member with respect to the direction intersecting with the axial direction when the outer shape of the elastic member changes.
It is provided with.

The invention according to claim 3 is the endless member rotation drive device according to claim 1 or 2,
The support having a first frame that supports the drive support member, and a second frame that supports the rotation support member and is swingably supported with respect to the first frame;
A position-restricting member that is supported by the rotation support member and configured to be able to contact a position restriction unit that restricts the position of the rotation support member with respect to a direction intersecting the axial direction;
An urging member for urging the rotation support member toward the position restricting portion;
It is provided with.

The invention according to claim 4 is the endless member rotation driving device according to claim 3,
The second frame body supported so as to be swingable with respect to the first frame body on both axial sides of the rotation support member;
The position restricting portion, the position restricting member, and the elastic member provided on both axial sides of the rotation support member;
It is provided with.

The invention according to claim 5 is the endless member rotation drive device according to claim 3,
The second frame body supported so as to be swingable with respect to the first frame body on one end side in the axial direction of the rotation support member;
The position restricting portion that restricts the position of the endless member in a state in which the rotation support member is inclined so that a force that moves the endless member toward the one end side acts;
It is provided with.

The invention according to claim 6 is the endless member rotation drive device according to any one of claims 1 to 5,
The elastic member constituted by a disk-shaped elastic mass supported by the shaft of the rotation support member;
It is provided with.

The invention according to claim 7 is the endless member rotation drive device according to any one of claims 1 to 5,
The elastic member constituted by a leaf spring in which both bent ends are supported by the shaft of the rotation support member;
It is provided with.

The invention according to claim 8 is the endless member rotation drive device according to any one of claims 1 to 5,
The elastic member configured by a leaf spring having one end supported by the shaft of the rotation support member and the other end fixedly supported;
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 9,
The endless member rotation drive device according to any one of claims 1 to 8, wherein the endless member rotation driving device is configured by a medium transport device that adsorbs and transports a medium to the surface of a strip-shaped endless member;
A visible image forming apparatus for forming a visible image on the medium;
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 10,
A visible image forming apparatus for forming a visible image;
A primary transfer device for transferring a visible image formed by the visible image forming apparatus to the surface of an intermediate transfer member constituted by the band-shaped endless member;
An endless member rotation driving device according to any one of claims 1 to 8, comprising an intermediate transfer member driving device including the intermediate transfer member;
A secondary transfer device for secondary transfer of the visible image on the surface of the intermediate transfer member to a medium;
It is provided with.

According to the first aspect of the present invention, the deviation of the endless member can be corrected with a simple and inexpensive configuration as compared with the case where the configuration of the present invention is not provided.
According to the second aspect of the present invention, the deviation of the endless member can be corrected with a simple and inexpensive configuration as compared with the case where the configuration of the present invention is not provided.
According to the third aspect of the invention, since the deviation can be corrected by the movement in the direction away from and in contact with the position restricting portion with reference to the position restricting portion, the deviation correction can be stabilized.

According to the fourth aspect of the present invention, the other end can be swung with a simple configuration while the one end is restricted by the position restricting portion, and the one end is simplified while the other end is restricted by the position restricting portion. Since rocking can be performed with a simple structure, it is possible to suppress excessive rocking compared to rocking both ends simultaneously.
According to the fifth aspect of the present invention, the difference in the elastic deterioration over time of the elastic member can be ignored as compared with the case of swinging at both ends.
According to invention of Claim 6, compared with the case where it does not have the structure of this invention, it can be set as the simple and cheap structure of a disk-shaped elastic lump.

According to the seventh aspect of the present invention, a simple and inexpensive configuration of a bent leaf spring can be achieved as compared with the case where the configuration of the present invention is not provided.
According to the eighth aspect of the present invention, it is possible to achieve a simple and inexpensive configuration by using a leaf spring that is stably supported as compared with the case without the configuration of the present invention.
According to the ninth aspect of the invention, compared to the case without the configuration of the present invention, it is possible to correct the deviation of the medium and prevent the image quality from being deteriorated due to the positional deviation of the medium with a simple and inexpensive configuration.

  According to the tenth aspect of the present invention, compared with the case where the configuration of the present invention is not provided, an image that is primarily transferred to the intermediate transfer member by correcting the deviation of the intermediate transfer member with a simple and inexpensive configuration. It is possible to prevent the image quality from being deteriorated due to the displacement of the image secondarily transferred to the medium.

Next, specific examples of embodiments of the present invention (hereinafter referred to as examples) will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow heading from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.
In the following description using the drawings, illustrations other than members necessary for the description are omitted as appropriate for easy understanding.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention.
FIG. 2 is an enlarged perspective view of a main part of the belt module according to the first embodiment of the present invention.
FIG. 3 is an explanatory diagram of the belt module of FIG. 2 with the medium transport belt removed.
FIG. 4 is a view showing a main part when the belt module is attached to the printer. In FIG. 4, the illustration of the rear frame and the like is omitted.
In FIG. 1, a printer U as an example of an image forming apparatus according to the first exemplary embodiment of the present invention has a sheet feeding container TR1 that accommodates a recording medium S as an example of a medium on which an image is recorded accommodated in a lower portion. A medium discharge part TRh is provided on the upper surface. An operation unit UI is provided in the upper left part of the printer U.
The printer U according to the first exemplary embodiment includes an image forming apparatus main body U1 and an opening / closing section U2 that can be opened and closed about a rotation center U2a provided at a lower right end of the image forming apparatus main body U1. The opening / closing unit U2 is provided with an open position for opening the inside of the image forming apparatus main body U1 in order to replenish developer, replace a failed member, or remove a paper jammed recording medium S, and a normal image forming operation is performed. It is configured to be movable between a closed position that is sometimes held.

  The printer U includes a control unit C that performs various controls of the printer U, an image processing unit GS whose operation is controlled by the control unit C, an image writing device driving circuit DL, a power supply device E, and the like. The power supply device E includes charging rolls CRy, CRm, CRc, CRk as examples of a charger to be described later, developing rolls G1y, G1m, G1c, G1k as examples of a developer holder, and a transfer roll T1y as an example of a transfer unit. , T1m, T1c, T1k, etc.

  The image processing unit GS converts print information input from an external image information transmission device or the like into latent images corresponding to four color images of Y (yellow), M (magenta), C (cyan), and K (black). The image information is converted into image information for image formation and output to the image writing device driving circuit DL at a predetermined timing. The image writing device driving circuit DL outputs a driving signal to the latent image writing device ROS according to the input image information of each color. The latent image writing device ROS emits laser beams Ly, Lm, Lc, and Lk as an example of image writing light for image writing of each color in accordance with a drive signal.

In FIG. 1, a toner image as an example of a visible image of each color of Y (yellow), M (magenta), C (cyan), and K (black) is formed on the right side of the latent image writing device ROS. Process cartridges UY, UM, UC, UK as an example of a visible image forming apparatus are arranged.
1 and 4, a K (black) process cartridge UK has a photosensitive member Pk as an example of a rotating image carrier. Around the photosensitive member Pk, there are a charging roll CRk as an example of a charger, a developing device Gk that develops an electrostatic latent image on the surface of the photosensitive member Pk into a visible image, a neutralizing member Jk that neutralizes the surface of the photosensitive member Pk, A photoconductor cleaner CLk as an example of an image carrier cleaner that removes the developer remaining on the surface of the photoconductor Pk is disposed.

In FIG. 1 and FIG. 4, after the surface of the photoconductor Pk is uniformly charged by the charging roll CRk in the charging area Q1k facing the charging roll CRk, a latent image is formed by the laser beam Lk in the latent image forming area Q2k. Written. The written electrostatic latent image is visualized in the developing area Qgk facing the developing device Gk.
The black process cartridge UK according to the first exemplary embodiment is configured by a detachable body in which a photoconductor Pk, a charging roll CRk, a developing device Gk, a charge eliminating member Jk, a photoconductor cleaner CLk, and the like are integrally configured. Is configured to be detachable from the image forming apparatus main body U1 in a state in which is moved to the open position.
The process cartridges UY, UM, and UC of other colors are configured to be detachable from the image forming apparatus main body U1 in the same manner as the black process cartridge UK.

  1 to 4, a belt module BM as an example of an endless member rotation driving device supported by an opening / closing portion U2 is disposed on the right side of the photoreceptors Py to Pk. The belt module BM includes a medium conveyance belt B as an example of an endless member, a drive roll Rd as an example of a drive support member that supports the medium conveyance belt B, and a driven roll Rj as an example of a rotation support member. A belt support roll (Rd + Rj) as an example of a conveying member support system, transfer rolls T1y to T1k as an example of a transfer device arranged to face each of the photoconductors Py to Pk, and an example of an image density detection member An image density sensor SN1, a belt cleaner CLb as an example of a holding and conveying member cleaner, and an example of a recording medium adsorbing member that is disposed opposite to the driven roll Rj and adsorbs the recording medium S to the medium conveying belt B. Medium adsorbing roll Rk. The medium transport belt B is rotatably supported by the belt support roll (Rd + Rj). The image density sensor SN1 is for detecting the density of a density detection image formed by an image density adjusting means (not shown) of the control unit C, that is, a so-called patch image, at a predetermined time. The adjusting means adjusts the voltage applied to the charging rolls CRy to CRk, the developing devices Gy to Gk and the transfer rolls T1y to T1k based on the image density detected by the image density detecting member, and the intensity of the laser beams Ly to Lk. Thus, image density adjustment and correction, so-called process control, is performed.

The recording medium S in the paper supply container TR1 disposed below the medium conveyance belt B is taken out by the paper supply member Rp and conveyed to the recording medium conveyance path SH.
The recording medium S in the recording medium conveyance path SH is conveyed by a medium conveyance roll Ra as an example of a recording medium conveyance member, and is sent to a registration roll Rr as an example of a paper feed timing adjustment member. The registration roll Rr transports the recording medium S to a recording medium suction position Q6 that is a region where the driven roll Rj and the medium suction roll Rk face each other at a predetermined timing. The recording medium S conveyed to the recording medium adsorption position Q6 is electrostatically adsorbed to the medium conveyance belt B.
When paper is fed from the manual paper feed unit TR0, the recording medium S fed by the manual paper feed member Rp1 is conveyed to the registration roll Rr by the medium conveyance roll Ra and conveyed to the medium conveyance belt B.

The recording medium S adsorbed on the medium conveying belt B sequentially passes through the transfer areas Q3y, Q3m, Q3c, and Q3k that are in contact with the photoreceptors Py to Pk.
In the transfer areas Q3y to Q3k, the transfer rolls T1y to T1k disposed on the back side of the medium conveying belt B are transferred at a predetermined timing from the power supply circuit E controlled by the control unit C with a polarity opposite to the toner charging polarity. A voltage is applied.
In the case of a multicolor image, the toner images on the respective photoreceptors Py to Pk are transferred onto the recording medium S on the medium conveying belt B by the transfer rolls T1y to T1k. In the case of a monochromatic image, so-called monochrome image, only a K (black) toner image is formed on the photoreceptor Pk, and only this K (black) toner image is transferred to the recording medium S by the transfer roll T1k. .
After the toner images are transferred, the photoreceptors Py to Pk are neutralized by the neutralization members Jy to Jk in the neutralization areas Qjy to Qjk, and then the toner remaining on the surface is collected by the photoreceptor cleaners CLy to CLk in the cleaning areas Q4y to Q4k. And then charged again by the charging rolls CRy to CRk.

The recording medium S to which the toner image has been transferred is in contact with a heating roll Fh as an example of a heating fixing member of a fixing device F as an example of a fixing device and a pressure roll Fp as an example of a pressure fixing member. Fixing is performed in the fixing region Q5 formed in this manner. The recording medium S on which the image is fixed is guided by a guide roller Rgk as an example of a guide member, and is discharged from a discharge roll Rh as an example of a medium discharge member to the medium discharge unit TRh.
The medium conveying belt B after the recording medium S is separated is cleaned by the belt cleaner CLb.
When duplex printing is performed, the discharge roll Rh is driven in reverse rotation, the recording medium S is conveyed to the medium reversal path SH2 by the switching member GT1, and is retransmitted to the registration roll Rr with the front and back reversed.
Note that the fixing device F, the lower drive roller of the discharge roller Rh, the switching member GT1, and the lower guide surface of the medium reversing path SH2 in the first embodiment are integrated and replaceable fixing devices, so-called fixing units. It is comprised by U3. The driven member on the upper side of the discharge roll Rh is supported by the opening / closing part U2.

2 and 3, the belt module BM has a frame 1 as an example of a support that supports the medium transport belt B. The frame body 1 includes a front front first frame body 2, a rear rear first frame body 3, and a connecting frame body 4 that connects the front first frame body 2 and the rear first frame body 3. have. The connection frame body 4 has a lower connection frame body 4a and an upper connection frame body 4b extending substantially in parallel, and the connection frame bodies 4a and 4b are respectively formed of the front first frame body 2 and the rear first frame. The frame 3 is connected.
The lower connecting frame 4a and the upper connecting frame 4b are connected by two interframe connecting members 4c and 4d.

The front first frame body 2 and the rear first frame body 3 are formed with a pair of front and rear bearing support portions 2a and 3a that support a bearing Rd2 that receives the shaft Rd1 of the drive roll Rd. The bearing support portions 2a and 3a are formed by a V-shaped groove shape having a tip on the lower side when viewed from the front, so-called a V-groove.
Second frame body support portions 2 c and 3 c are formed at lower ends of the front first frame body 2 and the rear first frame body 3.
A spring one end mounting portion 2 b is formed on the front side of the lower end portion of the front first frame body 2 and on the rear side of the lower end portion of the rear first frame body 3. In FIG. 3, the illustration of the rear spring one end mounting portion is omitted.
In FIG. 3, as indicated by a two-dot chain line, the transfer rolls T1k, T1c, T1m, and T1y are substantially parallel below the drive roll Rd between the front first frame 2 and the rear first frame 3. It is disposed and supported while receiving a force that moves in a direction to be pressed against the photoreceptors Pk, Pc, Pm, and Py by a rotatable spring (not shown).
A first frame 2 + 3 + 4 of the first embodiment is configured by the front first frame 2, the rear first frame 3, the connection frame 4, and the like.

The second frame body support portions 2c and 3c at the lower end portions of the front first frame body 2 and the rear first frame body 3 have a front second frame body 8 and a rear side centered on rocking shafts 6 and 7, respectively. The second frame body 9 is rotatably supported.
On the front side of the upper end portion of the front second frame body 8 and on the rear side of the upper end portion of the rear second frame body 9, a pair of front and rear spring other end mounting portions 8b are formed. In addition, illustration of the one end attachment part of the rear spring is omitted in FIG.
The front second frame body 8 and the rear second frame body 9 are formed with a pair of front and rear bearing mounting portions 8a and 9a for supporting a bearing Rj2 that receives the shaft Rj1 of the driven roll so as to be movable in the vertical direction. ing. A tension spring 11 for biasing the bearing Rj2 downward is attached to the bearing mounting portions 8a and 9a.
The front second frame body 8 and the rear second frame body 9 constitute a second frame body 8 + 9 of the first embodiment, and the first frame body 2 + 3 + 4 and the second frame body 8 + 9 form the second frame body 8 + 9. The frame 1 is configured.
Therefore, in the frame body 1 of the first embodiment, the second frame body 8 + 9 is supported so as to be swingable about the swing shafts 6 and 7 with respect to the first frame body 2 + 3 + 4.

3 and 4, the swing shafts 6 and 7 are mounted with main bodies 12a of torsion springs 12 and 13 as examples of urging members. One end 12b of the torsion springs 12, 13 is supported by the spring one end mounting portion 2b, and the other end 12c is supported by the spring other end mounting portion 8b.
Therefore, as shown in FIG. 4, the driven roll Rj supported by the second frame 8 + 9 supported by the torsion springs 12 and 13 so as to be swingable with respect to the first frame 2 + 3 + 4 is an example of a position restricting portion. The force pressed against the butting wall 14 is always acting. The abutting wall 14 can be arranged at any position except for the directions of the arrows X and -X. Here, an example in which the abutting wall 14 is arranged at a position where the position is restricted in the Y direction will be described.

FIG. 5 is a view as seen from the lower side in FIG. 4, FIG. 5A is an explanatory view showing a state where no deviation occurs, and FIG. 5B is an explanatory view showing a state where the deviation occurs.
The driven roll Rj includes the shaft Rj1 that is rotatably supported by the bearing Rj2, and a driven roll body Rj3 that is supported to be movable in the axial direction with respect to the shaft Rj1. A disc-like front pressing member 16 and a rear pressing member 17 that move in the axial direction as the driven roll main body Rj3 moves in the axial direction are attached to both front and rear ends of the driven roll main body Rj3.
On the front side of the front pressing member 16 and the rear side of the rear pressing member 17, disc-shaped front elastic members 18 and rear elastic members 19 each formed of an elastic mass as an example of an elastic member are provided on the axis Rj1. It is supported by.
An example of a position restricting member formed in a disk shape having a larger radius than the front elastic member 18 and the rear elastic member 19 in the natural state on the front side of the front elastic member 18 and the rear side of the rear elastic member 19. The front-side positioned member 21 and the rear-side positioned member 22 are supported by the shaft Rj1.

(Operation of Example 1)
In the endless member rotation drive device of Example 1 having the above-described configuration, the second frame body 8 + 9 is rotated with respect to the first frame body 2 + 3 + 4, and the distance between the drive roll Rd and the driven roll Rj is reduced. Then, by attaching the medium conveying belt B and rotating the second frame 8 + 9, the distance between the drive roll Rd and the driven roll Rj is increased as shown in FIGS. The medium conveying belt B is stretched.
Then, by pressing the second frame body 8 + 9 against the abutting wall 14 side by the torsion springs 12 and 13, the front positioned member 21 and the rear positioned member 22 are positioned in contact with the abutting wall 14. .

When the image forming operation is started and the medium transport belt B is rotated, the drive roll Rd and the driven roll Rj are not actually arranged in parallel, so that the media transport belt B is offset.
In FIG. 5B, when the driven roll main body Rj3 moves in the axial direction of the axis Rj1 along with the deviation of the medium conveying belt B, the front pressing member 16 or the rear pressing member 17 arranged on the moving direction side becomes the front elastic member. It contacts the member 18 or the rear elastic member 19.

  When the front elastic member 18 or the rear elastic member 19 is pressed and elastically deformed by the front pressing member 16 or the rear pressing member 17, the outer diameter becomes large. When the outer diameter of the elastic member 18 or the rear elastic member 19 that is elastically deformed becomes larger than the front-positioned member 21 or the rear-positioned member 22, the front-side elastic member 18 or the rear-side elastic member 19. The outer peripheral surface of the contact portion contacts the abutting wall 14.

Thereby, the front second frame body 8 or the rear second frame body 9 on the side of the front elastic member 18 or the rear elastic member 19 which is elastically deformed resists the spring force of the torsion springs 12 and 13. It rotates and the axis Rj1 of the driven roll Rj is inclined. Due to the inclination of the driven roll Rj, a force in a direction to correct the deviation acts on the medium transport belt B.
When the deviation of the medium conveying belt B is corrected and the driven roll body Rj3 moves in a direction in which the front pressing member 16 or the rear pressing member 17 moves away from the elastic elastically deformed front elastic member 18 or rear elastic member 19. The front elastic member 18 and the rear elastic member 19 are elastically restored, and the front positioned member 21 and the rear positioned member 22 come into contact with the abutting wall 14 to return to the state shown in FIG. 5A.

  Further, in the first exemplary embodiment, no protruding members, so-called ribs, are provided on the edges of the both ends in the axial direction of the driving roll Rd and the driven roll Rj of the medium conveying belt B, and the medium conveying is performed during the image forming operation. The belt B receives driving force from the driving roll Rd and is rotated in a state where the front and back surfaces are flat. That is, in the first embodiment, the medium conveying belt B is configured such that ribs or the like are bonded to the front and back and the medium conveying belt B is guided by the protruding portions of the ribs, or the direction of the medium conveying belt B intersecting the belt rotation direction. The flat surface state is maintained both when stationary and when rotated, without having a configuration in which the end portion rides on a tapered member to distort and project the planar state. This eliminates the need for protruding portions such as bonded ribs and simplifies the process, reduces unnecessary stress that is applied when the medium transport belt B is rotated, prevents damage to the medium transport belt B, and shifts the image position. Helps to suppress. That is, when a protruding portion such as a rib for guiding the medium conveying belt B is adhered to the medium conveying belt B, a place where the medium conveying belt B and the driving roll Rd and the driven roll Rj are in contact with each other, a rib or the like Since the protruding portion is different from the place where the driving roll Rd and the driven roll Rj come into contact, a circumferential speed difference is generated between the rotating medium conveying belt B and the protruding portion such as a rib, and this circumferential speed difference causes stress on the medium conveying belt B. This is prevented in the first embodiment. Further, when the end of the medium transport belt B rides on a tapered member, the end of the medium transport belt B is distorted and stress is applied to the medium transport belt B, but this is prevented in the first embodiment. .

6A and 6B are explanatory views of the main part of the belt module according to the second embodiment of the present invention. FIG. 6A is an explanatory view showing a state where no deviation occurs, and FIG. 6B is an explanatory view showing a state where the deviation occurs. 6C is an explanatory view of a leaf spring for tilting the shaft.
Next, a second embodiment of the present invention will be described. In the description of the second embodiment, components corresponding to those of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. To do.
This embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.

In FIG. 6, the follower roll Rj of the second embodiment omits the front pressing member 16 and the rear pressing member 17 of the first embodiment, and replaces the front elastic member 18 and the rear elastic member 19 with an elastic member. As an example, axially inclined leaf springs 26 and 27 are supported on a shaft Rj1 of a driven roll Rj so that the end portions 26b and 27b on the driven roll main body Rj3 side can move in the axial direction. 6A and 6C, the axially inclined leaf springs 26 and 27 are constituted by leaf springs obtained by bending a rectangular plate-like body into a V shape. The shaft tilting leaf springs 26 and 27 are opposed to the abutting wall 14 at V-shaped pointed edges 26a and 27a, and are brought into contact with and stopped when the shaft Rj1 rotates.
As shown in FIG. 6B, the distance between the pointed edges 26a and 27a and the axis Rj1 is such that the front-side positioned member 21 and the rear end are in the state where the shaft tilting leaf springs 26 and 27 are pushed and elastically deformed. It becomes longer than the outer diameter of the side-positioned member 22. 6A, the distance is set to be shorter than the outer diameters of the front-side positioned member 21 and the rear-side positioned member 22 in a state where the distance is not elastically deformed.

(Operation of Example 2)
In the endless member rotation driving apparatus of Example 2 having the above-described configuration, when the deviation of the medium transport belt B occurs in FIG. 6B and the driven roll body Rj3 moves in the axial direction of the axis Rj1, the endless member rotation driving apparatus The disposed shaft tilting leaf spring 26 is pushed by the driven roll body Rj3.
As shown in FIG. 6B, when the plate-inclining leaf springs 26 and 27 are pushed and elastically deformed by the driven roll body Rj3, the distance between the shaft Rj1 and the pointed edges 26a and 27a is increased. When the distance between the axis Rj1 and the pointed edges 26a, 27a is larger than the outer diameters of the front-side positioned member 21 and the rear-side positioned member 22, the pointed edges 26a, 27a of the shaft inclination leaf springs 26, 27 are , Contact the abutting wall 14.

Thereby, the front second frame body 8 or the rear second frame body 9 on the side of the axially inclined plate springs 26 and 27 elastically deformed similarly to the first embodiment resists the spring force of the torsion springs 12 and 13. It rotates and the axis Rj1 of the driven roll Rj is inclined. Due to the inclination of the axis Rj1, a force in a direction for correcting the deviation acts on the medium conveying belt B.
When the driven roll body Rj3 moves in a direction in which the offset of the medium conveying belt B is corrected and the elastically deformed shaft tilting leaf springs 26, 27 return to the natural state, the shaft tilting leaf springs 26, 27 is elastically restored, and the front-side positioned member 21 and the rear-side positioned member 22 come into contact with the abutting wall 14 to return to the state shown in FIG. 6A.

7A and 7B are explanatory views of a main part of the belt module according to the third embodiment of the present invention. FIG. 7A is an explanatory view showing a state where no deviation occurs, and FIG. 7B is an explanatory view showing a state where the deviation occurs. .
Next, the third embodiment of the present invention will be described. In the description of the third embodiment, the same reference numerals are given to the components corresponding to the components of the first embodiment, and the detailed description thereof will be omitted. To do.
This embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.

In FIG. 7, in the driven roll Rj of the third embodiment, the abutting wall 14, the front pressing member 16, and the rear pressing member 17 of the first embodiment are omitted. Further, instead of the front elastic member 18, the rear elastic member 19, the front positioned member 21 and the rear positioned member 22 of the first embodiment, shaft positioning leaf springs 31 and 32 as an example of an elastic member are used. Yes. The shaft positioning leaf springs 31 and 32 have shaft support end portions 31a and 32a, which are one end portions thereof, freely rotatable on the shaft Rj1 of the driven roll Rj and moved in the axial direction along with the axial movement of the driven roll body Rj3. Supported in a free state.
Fixed support end portions 31 b and 32 b which are the other end portions of the shaft positioning plate springs 31 and 32 are supported by fixed support portions 33 and 34 provided in the printer U.
In the shaft positioning leaf springs 31 and 32 of the third embodiment, the interval between the fixed support end portions 31b and 32b is set wider than the interval between the shaft support end portions 31a and 32a. The fixed support end portions 31b and 32b of the leaf springs 31 and 32 are disposed to the right of the driven roll shaft Rj1, and the spring force of the shaft positioning leaf springs 31 and 32 and the spring force of the torsion springs 12 and 13 are generated. In contrast, the position of Rj1 is held at the reference position shown in FIG. 7A.

(Operation of Example 3)
In the endless member rotation driving apparatus of Example 3 having the above-described configuration, in FIG. 7B, when the deviation of the medium transport belt B occurs and the driven roll body Rj3 moves in the axial direction of the axis Rj1, The shaft support end 31a of the disposed shaft positioning leaf spring 31 is pushed by the driven roll Rj3.
As shown in FIG. 7B, when the shaft support end 31a is pushed by the driven roll main body Rj3 and the shaft positioning leaf spring 31 is elastically deformed, the fixed support end 31b is fixed. The part 31a moves so as to draw an arc centered on the fixed support end part 31b.

Thus, in the same manner as in the first embodiment, the elastically deformed shaft positioning leaf springs 31 and 32 side front second frame body 8 or rear side second frame body 9 resists the spring force of the torsion springs 12 and 13. , And the axis Rj1 of the driven roll Rj is inclined as shown in FIG. 7B. Due to the inclination of the axis Rj1, a force in a direction for correcting the deviation acts on the medium conveying belt B.
When the driven roll body Rj3 moves in a direction in which the offset of the medium conveying belt B is corrected and the elastically deformed shaft positioning plate springs 31 and 32 return to the natural state, the shaft positioning plate springs 31 and 32 are elastic. Restore and return to the state shown in FIG. 7A.

FIG. 8 is an explanatory diagram showing a state where the medium transport belt is removed from the belt module according to the fourth embodiment of the present invention.
FIG. 9 is a view corresponding to FIG. 4 and shows a main part when the belt module of Embodiment 4 is attached to the printer. In FIG. 9, the illustration of the rear frame and the like is omitted.
FIG. 10 is a view as viewed from below in FIG. 9, FIG. 10A is an explanatory view showing a state in which no deviation occurs, and FIG. 10B is an explanatory view showing a state in which the deviation of the belt has occurred from the state of FIG. 10C is an explanatory diagram of a state in which a further deviation has occurred from the state of FIG. 10B.
Next, a description will be given of a fourth embodiment of the present invention. In the description of the fourth embodiment, components corresponding to the components of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. To do.
This embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.

In FIG. 8, in the belt module BM of the fourth embodiment, the torsion spring 13, the rear pressing member 17, the rear elastic member 19, and the rear positioned member 22 of the first embodiment are omitted. Then, instead of the rear first frame 3 and the rear second frame 9 of the first embodiment, a fixed frame 41 is used.
The fixed frame 41 is formed with a bearing support portion 41a configured similarly to the bearing support portion 3a of the first embodiment and a bearing mounting portion 41b configured similarly to the bearing mounting portion 9a of the first embodiment. . The bearing Rd2 is supported by the bearing support 41a, and the rear bearing Rj2 is held in a tiltable state by the tension applying spring 11 at the bearing mounting part 41b.
The front first frame 2, the fixed frame 41, the connecting frame 4, and the like constitute a support frame 2 + 41 + 4 as an example of the first frame.
Therefore, in the fourth embodiment, the front second frame body 8 is supported to be swingable about the swing shaft 6 with respect to the support frame body 2 + 41 + 4.

  9 and 10A, in the belt module BM according to the fourth embodiment, the positioning member 21 is applied to the abutting wall 14 disposed on the right side of the abutting wall 14 according to the first embodiment. The second frame 8 is held in a state of being rotated rightward with respect to the shaft holding portion 41b of the frame 41. For this reason, the axis Rj1 of the driven roll Rj is inclined as shown in FIG. 10A, and is set so that the medium transport belt B is naturally biased to the front side.

(Operation of Example 4)
In the endless member rotation driving apparatus according to the fourth embodiment having the above-described configuration, the medium transport belt B naturally shifts to the front side with the operation of the driven roll Rj. When the driven roll body Rj3 moves in the axial direction of the axis Rj1 along with the deviation, the front pressing member 16 comes into contact with the front elastic member 18 and is elastically deformed as shown in FIG. 10B. When the outer diameter of the front elastic member 18 becomes larger than the positioned member 21 due to elastic deformation, the outer peripheral surface of the front elastic member 18 contacts the abutting wall 14.
As a result, the front second frame 8 rotates against the spring force of the torsion spring 12, the axis Rj1 is inclined, and the deviation of the medium conveying belt B is reduced by the inclination of the axis Rj1.

From this state, when the medium transport belt B is further shifted to the front side, the front elastic member 18 is pushed by the front pressing member 16 along with the axial movement of the axis Rj1 of the driven roll body Rj3, and is further elastically deformed. As shown, the outer diameter is further increased and the axis Rj1 is further inclined. When the axis Rj1 is further inclined, the deviation of the medium conveying belt B is corrected.
When the deviation of the medium conveying belt B is corrected, the front elastic member 18 is elastically restored, the diameter thereof is reduced, and the state shown in FIG. 10A is restored after the state shown in FIG. 10B.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is performed within the range of the summary of this invention described in the claim. It is possible. Modification examples (H01) to (H05) of the present invention are exemplified below.
(H01) In each of the above-described embodiments, a printer as an example of an image forming apparatus has been illustrated. However, the present invention is not limited to this, and can be applied to a copying machine, a FAX, or a multifunction machine having a plurality of functions. Further, the present invention is not limited to an electrophotographic image forming apparatus, and can be applied to an image forming apparatus of an arbitrary image forming system such as an ink jet recording system, a thermal head system, or a lithographic printer. Further, the image forming apparatus is not limited to a multi-color developing image forming apparatus, and may be configured by a monochromatic, so-called monochrome image forming apparatus. Furthermore, it is not limited to an image forming apparatus of an arbitrary image forming method, such as products such as finished products and parts, delivered items such as books, DVDs and clothes, transported materials such as materials and waste materials handled at construction sites and construction sites, etc. Needless to say, the present invention can be applied to an endless member for carrying the article.

(H02) In the above-described embodiment, the medium conveying belt B is illustrated as an example of the endless member. However, the present invention is not limited to this, and the visible image is primarily transferred to the secondary image. The present invention can be applied to an endless member that may be displaced, such as an intermediate transfer belt used for transfer or a belt-like photosensitive belt.
(H03) In the first and fourth embodiments, the configuration in which the driven roll main body Rj3 is in contact with the front elastic member 18 and the rear elastic member 19 through the front pressing member 16 and the rear pressing member 17 is illustrated. It is not impossible to directly contact the elastic member when the driven roll main body Rj3 moves in the axial direction without using the member 16 and the rear pressing member 17.
(H04) In the second and third embodiments, both ends of the driven roll Rj are supported by the swingable frame bodies 8 and 9. However, the present invention is not limited to this, and only one end side of the driven roll Rj is used as in the fourth embodiment. It can also be supported by a swingable frame.
(H05) In the above-described embodiment, the frame 1 as an example of the support body in which the first frame body that supports the drive roll Rd and the second frame body that supports the driven roll Rj are connected is illustrated. The frame body that supports the drive roll Rd and the support body as the frame body that supports the driven roll Rj can be configured separately and independently.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is an enlarged perspective view of a main part of the belt module according to the first embodiment of the present invention. FIG. 3 is an explanatory diagram of the belt module of FIG. 2 with the medium transport belt removed. FIG. 4 is a view showing a main part when the belt module is attached to the printer. In FIG. 4, the illustration of the rear frame and the like is omitted. FIG. 5 is a view as seen from the lower side in FIG. 4, FIG. 5A is an explanatory view showing a state where no deviation occurs, and FIG. 5B is an explanatory view showing a state where the deviation occurs. 6A and 6B are explanatory views of the main part of the belt module according to the second embodiment of the present invention. FIG. 6A is an explanatory view showing a state where no deviation occurs, and FIG. 6B is an explanatory view showing a state where the deviation occurs. 6C is an explanatory view of a leaf spring for tilting the shaft. 7A and 7B are explanatory views of a main part of the belt module according to the third embodiment of the present invention. FIG. 7A is an explanatory view showing a state where no deviation occurs, and FIG. 7B is an explanatory view showing a state where the deviation occurs. . FIG. 8 is an explanatory diagram showing a state where the medium transport belt is removed from the belt module according to the fourth embodiment of the present invention. FIG. 9 is a view corresponding to FIG. 4 and shows a main part when the belt module of Embodiment 4 is attached to the printer. In FIG. 9, the illustration of the rear frame and the like is omitted. FIG. 10 is a view as viewed from below in FIG. 9, FIG. 10A is an explanatory view showing a state in which no deviation occurs, and FIG. 10B is an explanatory view showing a state in which the deviation of the belt has occurred from the state of FIG. 10C is an explanatory diagram of a state in which a further deviation has occurred from the state of FIG. 10B.

Explanation of symbols

1 ... support,
2 + 3 + 4, 2 + 41 + 4, the first frame,
8, 8 + 9 ... the second frame,
12, 13 ... biasing member,
14 ... Position restriction part,
18, 19 ... elastic mass, elastic member,
21, 22 ... Position restriction member,
26, 27, 31, 32 ... leaf springs, elastic members,
31a, 32a ... one end,
31b, 32b ... the other end,
B: Endless member,
BM: Medium transport device, endless member rotation drive device,
Rd: drive support member,
Rj: rotation support member,
Rj1 axis,
S ... medium
U: Image forming apparatus,
UY, UM, UC, UK: Visible image forming apparatus.

Claims (10)

An endless member that is rotated by receiving a driving force and is endless in a planar shape on the front and back sides,
A drive support member for supporting and driving the endless member;
A rotation support member that supports the endless member and rotates with rotation of the endless member;
A support that rotatably supports the rotation support member and supports the rotation support member so as to be movable in an axial direction of the rotation support member and swingable in a direction intersecting the axial direction;
An elastic member that is elastically deformed by movement in the axial direction of the rotation support member along with the deviation of the endless member and changes in outer shape in a direction intersecting the axial direction,
An endless member rotation driving device characterized in that the rotation support member is swung in a direction to correct a deviation of the endless member by changing the outer shape of the elastic member. An endless member that is rotated by receiving a driving force and is endless in a planar shape on the front and back sides,
A drive support member for supporting and driving the endless member;
A rotation support member that supports the endless member and rotates with rotation of the endless member;
A support that rotatably supports the drive support member and the rotation support member;
When the endless member is rotated, the endless member is supported so as to be movable in the axial direction with respect to the support as the endless member moves in the axial direction of the rotation support member. The rotation support member supported so as to be swingable in a direction intersecting the axial direction,
An elastic member that is elastically deformed by movement of the rotation support member in the axial direction and changes in outer shape in a direction intersecting the axial direction;
A position restricting portion for restricting the position of the rotation support member with respect to the direction intersecting with the axial direction and restricting the position of the elastic member with respect to the direction intersecting with the axial direction when the outer shape of the elastic member changes.
An endless member rotation drive device comprising: The support having a first frame that supports the drive support member, and a second frame that supports the rotation support member and is swingably supported with respect to the first frame;
A position-restricting member that is supported by the rotation support member and configured to be able to contact a position restriction unit that restricts the position of the rotation support member with respect to a direction intersecting the axial direction;
An urging member for urging the rotation support member toward the position restricting portion;
The endless member rotation drive device according to claim 1, wherein the endless member rotation drive device is provided. The second frame body supported so as to be swingable with respect to the first frame body on both axial sides of the rotation support member;
The position restricting portion, the position restricting member, and the elastic member provided on both axial sides of the rotation support member;
The endless member rotation driving device according to claim 3, comprising: The second frame body supported so as to be swingable with respect to the first frame body on one end side in the axial direction of the rotation support member;
The position restricting portion that restricts the position of the endless member in a state in which the rotation support member is inclined so that a force that moves the endless member toward the one end side acts;
The endless member rotation driving device according to claim 3, comprising: The elastic member constituted by a disk-shaped elastic mass supported by the shaft of the rotation support member;
An endless member rotation driving apparatus according to any one of claims 1 to 5, further comprising: The elastic member constituted by a leaf spring in which both bent ends are supported by the shaft of the rotation support member;
An endless member rotation driving apparatus according to any one of claims 1 to 5, further comprising: The elastic member configured by a leaf spring having one end supported by the shaft of the rotation support member and the other end fixedly supported;
An endless member rotation driving apparatus according to any one of claims 1 to 5, further comprising: The endless member rotation drive device according to any one of claims 1 to 8, wherein the endless member rotation driving device is configured by a medium transport device that adsorbs and transports a medium to the surface of a strip-shaped endless member;
A visible image forming apparatus for forming a visible image on the medium;
An image forming apparatus comprising: A visible image forming apparatus for forming a visible image;
A primary transfer device for transferring a visible image formed by the visible image forming apparatus to the surface of an intermediate transfer member constituted by the band-shaped endless member;
An endless member rotation driving device according to any one of claims 1 to 8, comprising an intermediate transfer member driving device including the intermediate transfer member;
A secondary transfer device for secondary transfer of the visible image on the surface of the intermediate transfer member to a medium;
An image forming apparatus comprising:

Images