JP7015482B2 - Image forming device - Google Patents

Description

The present invention relates to an image forming apparatus.

Image forming devices such as copiers, printers, facsimiles, or multifunction devices thereof are provided with many driving devices for image forming operations.

Patent Document 1 describes such a drive device for rotating a paper ejection roller, which is a driven body, in the forward rotation and the reverse rotation. This drive device includes an input shaft in which a rotary drive force is input from a drive motor which is a drive source capable of forward rotation and reverse rotation, and an output shaft in which a rotary drive force is output to a paper ejection roller. There are two drive transmission paths from the input shaft to the output shaft, and in order to selectively switch between the two drive transmission paths by engaging with the gear for transmitting the rotational driving force of the drive motor to the two drive transmission paths. One-way clutch is provided. When the drive motor rotates in the forward direction, the one-way clutch is locked, and the rotational driving force from the drive motor is transmitted to one of the drive transmission paths of the two systems via the gear. On the other hand, when the drive motor reverses, the one-way clutch idles, and the rotational driving force from the drive motor is transmitted to the other drive transmission path of the two drive transmission paths via the gear.

However, in the drive device described in Patent Document 1, since a one-way clutch is provided for selectively switching the drive transmission paths of the two systems, there arises a problem that the cost increases by that amount.

In order to solve the above problems, the present invention has a drive source capable of forward rotation and reverse rotation, and an image forming apparatus for driving a fixing roller and a resist roller as driven bodies by the drive source, in which the drive source is driven. A fixing roller drive transmitting means for transmitting a force to the fixing roller and a resist roller driving transmitting means for transmitting the driving force of the driving source to the resist roller are provided, and the fixing roller drive transmitting means and the resist roller drive transmission means are provided. The means is a drive that switches between two drive transmission paths for transmitting the drive force and a drive transmission path for transmitting the drive force of the drive source to the driven body among the two drive transmission paths. The two drive transmission paths include a transmission path switching means, in which one drive transmission path is composed of a plurality of pulleys and a belt member stretched on the pulleys, and the other drive transmission path is a plurality of. The drive transmission path switching means moves in different directions in the thrust direction between the two drive transmission paths during normal rotation and reverse rotation of the drive source. A rotatable moving rotating member that transmits a driving force from the driving source to one of the driving transmission paths of the two systems or the other driving transmission path is provided, and the moving rotating member is the above-mentioned moving rotating member. It is a gear that directly meshes with the gear of the output shaft of the drive source, and is characterized in that the deceleration ratio of the fixing roller and the resist roller is different between the normal rotation and the reverse rotation of the drive source.

As described above, according to the present invention, there is an excellent effect that the drive transmission path of the two systems can be selectively switched while suppressing the cost increase.

FIG. 3 is a schematic cross-sectional view of a drive device for driving a paper ejection roller according to a configuration example 1. The schematic block diagram of the printer which concerns on embodiment. FIG. 6 is a schematic cross-sectional view of a drive device at the time of motor reversal in which the motor is rotated in the direction opposite to that of FIG. Schematic cross-sectional view of a drive device when a worm gear is provided on the output shaft of a motor. Schematic cross-sectional view of the drive device according to the configuration example 2. FIG. 5 is a schematic cross-sectional view of a drive device at the time of motor reversal in which the motor is rotated in the direction opposite to that of FIG. Schematic cross-sectional view of the drive device according to the configuration example 3. Schematic cross-sectional view of the drive device according to the configuration example 4. The figure which shows the drive transmission composition of the drive device which concerns on Configuration Example 5. The figure which shows the drive transmission composition of the drive device which concerns on Configuration Example 6. The figure which shows the drive transmission composition of the drive device which concerns on Configuration Example 7.

[Embodiment 1]
Hereinafter, an embodiment of an electrophotographic printer (hereinafter, simply referred to as a printer) as an image forming apparatus to which the present invention is applied will be described. First, the basic configuration of this printer will be described. FIG. 2 is a schematic configuration diagram of a printer according to an embodiment. In the figure, this printer is equipped with four process units 160Y, 160C, 160M, 160K for forming toner images of yellow, cyan, magenta, and black (hereinafter referred to as Y, C, M, and K). There is. These use Y, C, M, and K toners of different colors as the image forming substance, but have the same configuration other than that, and are replaced at the end of the service life. Taking the process unit 160K for forming a K toner image as an example, it includes a drum-shaped photoconductor 161K as a latent image carrier, a developing device 162K, a charging device 163K, a drum cleaning device 164K, a static elimination device, and the like. The process unit 160K, which is an image forming unit, can be attached to and detached from the printer body, and consumable parts can be replaced at once.

The charging device 163K uniformly charges the surface of the photoconductor 161K which is rotated clockwise in the figure by the driving means. The surface of the uniformly charged photoconductor 161K is exposed and scanned by the laser beam L to carry an electrostatic latent image for K. The electrostatic latent image for K is developed into a Y toner image by a developing device 162K using K toner. Then, the intermediate transfer is performed on the intermediate transfer belt 179 described later. The drum cleaning device 164K removes the transfer residual toner adhering to the surface of the photoconductor 161K after the intermediate transfer step. Further, the static eliminator removes the residual charge of the photoconductor 161K after cleaning. By this static elimination, the surface of the photoconductor 161K is initialized to prepare for the next image formation. Similarly, in the process units 160Y, 160C, 160M of other colors, Y, C, M toner images are formed on the photoconductors 161Y, 161C, 161M and intermediately transferred onto the intermediate transfer belt 179, which will be described later. The tubular drum portion of the photoconductor 161K has an organic photosensitive layer coated on the front surface of a hollow aluminum base tube. Flange having a drum shaft is attached to both ends of the drum portion in the axial direction to form the photoconductor 161K. The developing apparatus 162K uses the K toner contained therein to be formed on the surface of the photoconductor 161K in a developing region which is a facing region between the developing roller 162aK and the photoconductor 161K as the developing roller 162aK rotates. It is attached to an electrostatic latent image for development and developed into a K toner image.

Although the process unit 160K for K has been described with reference to FIG. 2, in the process units 160Y, 160C, 160M for Y, C, and M, Y, is applied to the surface of the photoconductors 161Y, 161C, and 161M by the same process. A C and M toner image is formed.

In FIG. 2 shown above, the optical writing unit 165 is arranged above the process units 160Y, 160C, 160M, and 160K in the vertical direction. The optical writing unit 165, which is a latent image writing device, optically scans the photoconductors 161Y, 161C, 161M, 161K in the process units 160Y, 160C, 160M, 160K by the laser beam L emitted from the laser diode based on the image information. do. By this optical scanning, electrostatic latent images for Y, C, M, and K are formed on the photoconductors 161Y, 161C, 161M, and 161K. In such a configuration, the optical writing unit 165 and the process units 160Y, 160C, 160M, 160K make three or more latent image carriers Y, C, M, K toners having different colors from each other. It functions as an image-forming means for image-forming.

The optical writing unit 165 irradiates the photoconductor through a plurality of optical lenses and mirrors while polarizing the laser light emitted from the light source in the main scanning direction by a polygon mirror rotationally driven by a polygon motor. be. An LED array may be used in which light writing is performed by LED light emitted from a plurality of LEDs in the LED array.

Below the process units 160Y, 160C, 160M, and 160K in the vertical direction, a transfer unit 175, which is a belt device that allows endless movement in the counterclockwise direction in the figure while stretching an endless intermediate transfer belt 179, is arranged. .. The transfer unit 175 also includes a drive roller 176, a tension roller 177, a primary transfer roller 174Y, 174C, 174M, 174K, a secondary transfer roller 178, a belt cleaning device 171 and a cleaning backup roller 172. The intermediate transfer belt 179 is stretched by a drive roller 176, a tension roller 177, a cleaning backup roller 172, and four primary transfer rollers 174Y, 174C, 174M, 174K arranged inside the loop. Then, it is endlessly moved in the same direction by the rotational force of the drive roller 176 which is rotationally driven in the counterclockwise direction in the drawing by the drive means.

The four primary transfer rollers 174Y, 174C, 174M, 174K sandwich the intermediate transfer belt 179, which is endlessly moved in this way, between the photoconductors 161Y, 161C, 161M, and 161K. By this sandwiching, a primary transfer nip for Y, C, M, K in which the front surface of the intermediate transfer belt 179 and the photoconductors 161Y, 161C, 161M, 161K abut is formed. A primary transfer bias is applied to each of the primary transfer rollers 174Y, 174C, 174M, and 174K by a transfer bias power supply. As a result, a transfer electric field is formed between the electrostatic latent images of the photoconductors 161Y, 161C, 161M, and 161K and the primary transfer rollers 174Y, 174C, 174M, and 174K. Instead of the primary transfer rollers 174Y, 174C, 174M, 174K, a transfer charger, a transfer brush, or the like may be adopted.

When the Y toner formed on the surface of the photoconductor 161Y of the process unit 160Y for Y enters the above-mentioned primary transfer nip for Y as the photoconductor 161Y rotates, the photoconductor is affected by the action of the transfer electric field and the nip pressure. The primary transfer is performed from above 161Y onto the intermediate transfer belt 179. The intermediate transfer belt 179 on which the Y toner image is primarily transferred in this way is placed on the photoconductors 161M, 161C, 161K as it passes through the primary transfer nips for M, C, and K as it moves endlessly. The M, C, and K toner images are sequentially superimposed on the Y toner image and primaryly transferred. By this superposition primary transfer, a four-color toner image is formed on the intermediate transfer belt 179.

The secondary transfer roller 178 of the transfer unit 175 is arranged outside the loop of the intermediate transfer belt 179, and sandwiches the intermediate transfer belt 179 with the tension roller 177 inside the loop. By this sandwiching, a secondary transfer nip is formed in which the front surface of the intermediate transfer belt 179 and the secondary transfer roller 178 come into contact with each other. A secondary transfer bias is applied to the secondary transfer roller 178 by a transfer bias power supply. By this application, a secondary transfer electric field is formed between the secondary transfer roller 178 and the tension roller 177 connected to the ground.

Below the transfer unit 175 in the vertical direction, a paper feed cassette 141 accommodating a plurality of sheets of recording paper P in a stack of paper bundles is slidably and detachably arranged with respect to the printer housing. The paper feed cassette 141 has a paper feed roller 142 in contact with the recording paper P at the top of the paper bundle, and by rotating the paper feed roller 142 in the counterclockwise direction in the drawing at a predetermined timing, the paper feed cassette 141 is used. P is sent out toward the paper feed path.

A resist roller pair 143 composed of resist rollers 143a and 143b is arranged near the end of the paper feed path. The resist roller pair 143 stops the rotation of both rollers as soon as the recording paper, which is a recording member sent out from the paper feed cassette 141, is sandwiched between the rollers. Then, the rotation drive is restarted at a timing at which the sandwiched recording paper can be synchronized with the four-color toner image on the intermediate transfer belt 179 in the above-mentioned secondary transfer nip, and the recording paper P is sent out toward the secondary transfer nip. ..

The four-color toner image on the intermediate transfer belt 179, which is brought into close contact with the recording paper by the secondary transfer nip, is collectively secondary transferred onto the recording paper P under the influence of the secondary transfer electric field and the nip pressure, and is transferred to the recording paper P. Combined with the white color of, it becomes a full-color toner image. The transfer residual toner that was not transferred to the recording paper is attached to the intermediate transfer belt 179 after passing through the secondary transfer nip. This is cleaned from the belt surface by the belt cleaning device 171 abutting on the front surface of the intermediate transfer belt 179. The cleaning backup roller 172 disposed inside the loop of the intermediate transfer belt 179 backs up the cleaning of the belt by the belt cleaning device 171 from the inside of the loop.

When the recording paper P on which the full-color toner image is formed on the surface passes through the secondary transfer nip, the recording paper P is subjected to curvature separation from the secondary transfer roller 178 and the intermediate transfer belt 179. Then, it is sent to the fixing device 140, which is a fixing means, via the transfer path after transfer. The fixing device 140 is provided with a fixing roller 145 containing a heat generating source 145a such as a halogen lamp, and a pressurizing roller 147 that rotates while abutting on the fixing roller 145 at a predetermined pressure. A fixing nip is formed by the pressure roller 147. The recording paper fed into the fixing device 140 is sandwiched between the fixing nips so that the surface supporting the unfixed toner image is brought into close contact with the fixing roller 145. Then, the toner in the toner image is softened by the influence of heating and pressurization, and the full-color image is fixed.

When the single-sided print mode is set by an input operation to the operation unit or a control signal sent from a personal computer or the like, the recording paper P discharged from the fixing device 140 is a pair of paper ejection rollers that rotate in the normal direction. By 181 it is discharged to the outside of the machine as it is. Then, it is stacked on the stack portion 150 which is the upper surface of the upper cover of the housing.

Further, the paper ejection roller pair 181 ejects the recording paper P conveyed from the fixing device 140 to the stack portion 150, while the paper ejection roller pair 181 is reversed when the double-sided print mode is set. The recording paper P is switched back to the refeed path 170 side. That is, the paper ejection roller pair 181 includes a pair of paper ejection rollers 181a and 181b, and when the recording paper P detects a nip state in which the end portion is sandwiched between the paper ejection rollers 181a and 181b by the paper ejection sensor 182, the paper ejection roller pair 181 is ejected. The paper rollers 181a and 181b are reversed. As a result, the recording paper P is conveyed by the double-sided roller 183, passes through the refeed path 170, and is conveyed to the secondary transfer nip again in a state where the front and back sides are reversed in the direction in which transfer is possible to the back surface thereof. Then, after passing through the secondary transfer nip and forming a toner image on the back surface of the recording paper P, the toner image is fixed on the recording paper P by the fixing device 140 and discharged to the stack portion 150 by the paper ejection roller pair 181. Toner. In the present embodiment, the paper ejection roller 181a of the paper ejection roller pair 181 is rotationally driven by the drive device 30 described later, but at least one paper ejection roller of the paper ejection roller pair 181 is rotationally driven by the drive device 30. It may be configured as follows.

[Configuration Example 1]
FIG. 1 is a schematic cross-sectional view of a drive device 30 for driving a paper ejection roller 181a according to a configuration example 1. As shown in FIG. 1, the drive device 30 includes a motor 1 which is a drive source capable of forward / reverse rotation, and the motor 1 is attached to a side plate 131. A Hassuba gear 1a is provided on the output shaft of the motor 1, and the Hassuba gear 1a and the idler gear 2 which is a Hassuba gear mesh with each other. The idler gear 2 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 2a and drive connecting claws 2b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 9 rotatably supported by the fixed shaft S1 facing the idler gear 2, a plurality of drive connecting holes 9a into which a plurality of drive connecting claws 2a are fitted are formed on the rotation trajectory of the drive connecting claws 2a. It is formed. Then, the idler gear 2 moves toward the external tooth gear 9 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 2a fits into the drive connecting hole 9a, so that the idler gear 2 and the external tooth gear 9 engage with each other. It is possible. Further, on the side surface of the pulley 3 rotatably supported by the fixed shaft S1 facing the idler gear 2, a plurality of drive connecting holes 3a into which a plurality of drive connecting claws 2b are fitted are formed on the rotation trajectory of the drive connecting claws 2b. It is formed. Then, the idler gear 2 moves to the axial pulley 3 side while rotating on the fixed shaft S1, and the drive connecting claw 2b fits into the drive connecting hole 9a, so that the idler gear 2 and the pulley 3 can be engaged with each other. There is.

The fixed shaft S2 is fixed to the side plate 131 and the side plate 132 at a position displaced from the fixed shaft S1 to the paper ejection roller 181a side in the radial direction, and the rotating shaft 7 of the paper ejection roller 181a is provided on the side plate 132. It is rotatably supported by the bearing 132a. A pulley 5 that stretches the timing belt 4 together with the pulley 3 is rotatably supported on the fixed shaft S2. Further, the external tooth gear 10 that meshes with the external tooth gear 9 coaxially with the pulley 5 and the drive gear 6 that meshes with the external tooth gear 8 fixed to the rotating shaft 7 of the paper ejection roller 181a by the fixing pin 7a are rotatable. Is supported by.

The drive device 30 shown in FIG. 1 has a first drive transmission path R1 and a second drive transmission path R2, which are two systems of drive transmission paths for transmitting the driving force of the motor 1 to the paper ejection roller 181a. ing. The first drive transmission path R1 is composed of a pulley 3 which is a drive transmission member, a timing belt 4 and a pulley 5, and the second drive transmission path R2 is an external tooth gear 9 and an external tooth gear which are drive transmission members. It is composed of 10.

The direction F of the thrust force acting on the idler gear 2 from the hasba gear 1a is determined by the rotation direction of the motor 1 and the twisting direction of the hasba gear 1a. In FIG. 1, since the rotation direction of the motor 1 is the clockwise direction (CW) and the twisting direction of the hasba gear 1a is to the left, a thrust force acts on the idler gear 2 from the hasba gear 1a to the pulley 3 side. Therefore, the idler gear 2 moves toward the pulley 3 in the thrust direction, the drive connecting claw 2b fits into the drive connecting hole 3a, and the idler gear 2 and the pulley 3 engage with each other, so that the idler gear 2 drives the pulley 3. The pulley 3 drives the pulley 5 rotatably attached to the fixed shaft S2 via the timing belt 4. Then, the drive gear 6 arranged coaxially with the pulley 5 drives the external tooth gear 8 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 rotates in the same direction as the rotation direction of the motor 1 by the driving force transmitted from the first drive transmission path R1.

FIG. 3 is a schematic cross-sectional view of the drive device 30 at the time of motor reversal in which the motor 1 is rotated in the direction opposite to that of FIG. In the drive device 30 shown in FIG. 3, since the motor 1 is driven in the counterclockwise direction (CCW), a thrust force acts on the idler gear 2 from the hasba gear 1a to the external tooth gear 9 side. Therefore, the idler gear 2 moves toward the external tooth gear 9 in the thrust direction, the drive connecting claw 2a fits into the drive connecting hole 9a, and the idler gear 2 and the external tooth gear 9 engage with each other, so that the idler gear 2 becomes the external tooth. Drive the gear 9. The external tooth gear 9 drives the external tooth gear 10 arranged coaxially with the pulley 5. Then, the drive gear 6 arranged coaxially with the external tooth gear 10 drives the external tooth gear 8 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 is in the direction opposite to the rotating direction of the motor 1 due to the driving force transmitted from the second drive transmission path R2, and decelerates the pulley 3 / pulley 5. It is driven at a rotation speed different from the ratio.

In the drive device 30 according to this configuration example, the idler gear 2 is driven from the hasba gear 1a by moving the idler gear 2 in different thrust directions between the drive transmission paths of the two systems during the forward rotation and the reverse rotation of the motor 1. The drive transmission path to the gear 6 can be switched. That is, the idler gear 2 having a function of transmitting the rotational driving force from the motor 1 to each drive transmission path is also used as a member for selectively switching the drive transmission paths of the two systems. Therefore, in addition to the gear for transmitting the rotational driving force from the motor 1 to each drive transmission path, the one-way clutch is not provided as compared with the configuration in which the one-way clutch for selectively switching the drive transmission paths of the two systems is provided. The cost increase can be suppressed by that amount.

Here, in a configuration in which the idler gear 2 is moved in the radial direction to mesh with the external tooth gear 9 in order to switch the drive transmission path, a loud noise may be generated when the idler gear 2 and the external tooth gear 9 mesh with each other. On the other hand, in the configuration in which the idler gear 2 is moved in the thrust direction to fit the drive connecting claw 2a provided on the side surface of the idler gear 2 and the drive connecting hole 9a formed on the side surface of the external tooth gear 9, the gears are engaged with each other. Since there is no such noise, the generation of the loud noise can be suppressed. Therefore, by adopting a configuration in which the idler gear 2 is moved in the thrust direction to selectively switch between the two drive transmission paths as in the drive device 30 of this configuration example, noise reduction during drive transmission path switching is achieved. be able to.

Further, by setting the number of drive transmission members in the first drive transmission path R1 and the second drive transmission path R2 between the two fixed shafts S1 and the fixed shaft S2 to be odd and even, the rotation direction of the motor 1 can be changed. Even if it is changed, only the reduction ratio can be changed without changing the rotation direction of the paper ejection roller 181a.

Further, as the drive transmission path, it is possible to achieve quietness by using a timing belt like the first drive transmission path R1 rather than using only the external tooth gear as in the second drive transmission path R2. can. On the other hand, it is possible to improve the durability by using only the external tooth gear like the second drive transmission path R2, as compared with using the timing belt like the first drive transmission path R1. Therefore, for example, when the first drive transmission path R1 and the second drive transmission path R2 are configured so that the rotation direction and reduction ratio of the paper ejection roller 181a are the same, either quietness or durability is determined. Depending on whether or not the drive transmission path is taken, the drive transmission path may be switchable.

As shown in FIG. 4, the motor 1 is arranged so that the axial direction of the motor 1 is orthogonal to the axial direction of the fixed shaft S1 with respect to the drive device 30, and the output shaft of the motor 1 is set to the hasba gear. A configuration in which the worm gear 1b is used instead of 1a can also be adopted. Even with this configuration, the direction of the thrust force acting on the idler gear 2 which is a hasba gear is changed between the forward rotation and the reverse rotation of the motor 1 as described above, and the idler gear 2 is moved in the axial direction. The drive transmission path can be switched by moving in different directions.

Further, in this configuration example, even if the rotation speed of the motor 1 is the same between the normal rotation time and the reverse rotation time, the rotation speed of the motor 1 is controlled by a single control constant, and the rotation speed of the paper ejection roller 181a is controlled. Can be increased.

[Configuration Example 2]
FIG. 5 is a schematic cross-sectional view of the drive device 30 according to the configuration example 2. As shown in FIG. 3, the drive device 30 includes a motor 1 which is a drive source capable of forward / reverse rotation, and the motor 11 is attached to a side plate 131. A Hassuba gear 11a is provided on the output shaft of the motor 1, and the Hassuba gear 11a and the idler gear 12 are in mesh with each other. The idler gear 12 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 12a and drive connecting claws 12b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 18 rotatably supported by the fixed shaft S1 facing the idler gear 12, a plurality of drive connecting holes 18a into which a plurality of drive connecting claws 12a are fitted are formed on the rotation trajectory of the drive connecting claws 12a. It is formed. Then, the idler gear 12 moves toward the external tooth gear 18 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 12a fits into the drive connecting hole 18a, so that the idler gear 12 and the external tooth gear 18 engage with each other. It is possible. Further, on the side surface of the external tooth gear 13 rotatably supported by the fixed shaft S1 facing the idler gear 12, a plurality of drive connecting holes 13a into which a plurality of drive connecting claws 12b are fitted are provided in the rotation trajectory of the drive connecting claw 12b. Formed on top. Then, the idler gear 12 moves toward the external tooth gear 13 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 12b fits into the drive connecting hole 13a, so that the idler gear 12 and the external tooth gear 13 engage with each other. It is possible.

The fixed shaft S2 is fixed to the side plate 131 and the side plate 132 at a position displaced from the fixed shaft S1 to the paper ejection roller 181a side in the radial direction, and the rotating shaft 7 of the paper ejection roller 181a is provided on the side plate 132. It is rotatably supported by the bearing 132a. An external tooth gear 14 that meshes with the external tooth gear 13 is rotatably supported on the fixed shaft S2. Further, the external tooth gear 20 that meshes with the external tooth gear 18 coaxially with the external tooth gear 14 and the drive gear 15 that meshes with the external tooth gear 17 fixed to the rotating shaft 7 of the paper ejection roller 181a by the fixing pin 7a. It is rotatably supported.

In the drive device 30 shown in FIG. 5, the first drive transmission path R1 which is one of the two drive transmission paths for transmitting the drive force of the motor 11 to the paper ejection roller 181a is an external tooth which is a drive transmission member. It is composed of a gear 13 and an external tooth gear 14. Further, the second drive transmission path R2, which is the other of the two drive transmission paths, is composed of the external tooth gear 18, the external tooth gear 19, and the external tooth gear 20 which are drive transmission members.

The direction F of the thrust force acting on the idler gear 12 from the hasba gear 11a is determined by the rotation direction of the motor 11 and the twisting direction of the hasba gear 11a. In FIG. 5, since the rotation direction of the motor 11 is the clockwise direction (CW) and the twisting direction of the hasba gear 11a is to the left, a thrust force acts on the idler gear 12 from the hasba gear 11a to the external tooth gear 13 side. Therefore, the idler gear 12 moves toward the external tooth gear 13 in the thrust direction, the drive connecting claw 12b is fitted into the drive connecting hole 13a, and the idler gear 12 and the external tooth gear 13 engage with each other, so that the idler gear 12 becomes the external tooth. Drive the gear 13. The external tooth gear 13 drives an external tooth gear 14 rotatably attached to the fixed shaft S2. Then, the drive gear 15 arranged coaxially with the external tooth gear 14 drives the external tooth gear 17 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 rotates in the same direction as the rotation direction of the motor 11 by the driving force transmitted from the first drive transmission path R1.

FIG. 6 is a schematic cross-sectional view of the drive device 30 at the time of motor reversal in which the motor 11 is rotated in the direction opposite to that of FIG. In the drive device 30 shown in FIG. 3, since the motor 11 is driven in the counterclockwise rotation direction, a thrust force acts on the idler gear 12 from the hasba gear 11a to the external tooth gear 18 side. Therefore, the idler gear 12 moves toward the external tooth gear 18 in the thrust direction, the drive connecting claw 12a is fitted into the drive connecting hole 18a, and the idler gear 12 and the external tooth gear 18 engage with each other, so that the idler gear 12 becomes the external tooth. Drive the gear 18. The external tooth gear 18 drives the external tooth gear 20 arranged coaxially with the fixed shaft S2 via the external tooth gear 19 rotatably supported by the fixed shaft S3. Then, the drive gear 15 arranged coaxially with the external tooth gear 20 drives the external tooth gear 17 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, in the paper ejection roller 181a provided on the rotating shaft 7, the paper ejection roller 181a is in the direction opposite to the rotation direction of the motor 11 due to the driving force transmitted from the second drive transmission path R2, and the external teeth It is driven at a rotation speed different from the reduction ratio of the gear 13 / external tooth gear 14.

Further, by setting the number of drive transmission members in the first drive transmission path R1 and the second drive transmission path R2 between the two fixed shafts S1 and the fixed shaft S2 to be odd and even, the rotation direction of the motor 11 can be changed. Even if it is changed, only the reduction ratio can be changed without changing the rotation direction of the paper ejection roller 181a.

Further, as in the drive device 30 according to the present configuration example, by configuring both the first drive transmission path R1 and the second drive transmission path R2 only with the external tooth gear, two highly durable drive transmission systems are used. Drive transmission can be performed by a route, and eventually the life of the drive device 30 can be extended.

[Configuration Example 3]
FIG. 7 is a schematic cross-sectional view of the drive device 30 according to the configuration example 3. As shown in FIG. 7, the drive device 30 includes a motor 21 which is a drive source capable of forward / reverse rotation, and the motor 21 is attached to the side plate 131. A Hassuba gear 21a is provided on the output shaft of the motor 21, and the Hassuba gear 21a and the idler gear 22 are in mesh with each other. The idler gear 22 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 22a and a plurality of drive connecting claws 22b are provided on both side surfaces in the axial direction. On the side surface of the internal gear 23 rotatably supported by the fixed shaft S1 facing the idler gear 22, a plurality of drive connecting holes 23a into which a plurality of drive connecting claws 22a are fitted are formed on the rotation trajectory of the drive connecting claws 22a. It is formed. Then, the idler gear 22 moves toward the internal tooth gear 23 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 22a fits into the drive connecting hole 23a, so that the idler gear 22 and the internal tooth gear 23 engage with each other. It is possible. Further, on the side surface of the external tooth gear 27 rotatably supported by the fixed shaft S1 facing the idler gear 22, a plurality of drive connecting holes 27a into which a plurality of drive connecting claws 22b are fitted are provided in the rotation trajectory of the drive connecting claw 22b. Formed on top. Then, the idler gear 22 moves toward the external tooth gear 27 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 22b fits into the drive connecting hole 27a, so that the idler gear 22 and the external tooth gear 27 engage with each other. It is possible.

The fixed shaft S2 is fixed to the side plate 131 at a position displaced to the side of the paper ejection roller 181a in the radial direction with respect to the fixed shaft S1, and the rotating shaft 7 of the paper ejection roller 181a is attached to the bearing 132a provided on the side plate 132. It is rotatably supported. An external tooth gear 28 that meshes with the external tooth gear 27 is rotatably supported on the fixed shaft S2. Further, the external tooth gear 24 that meshes with the internal tooth gear 23 coaxially with the external tooth gear 28 and the drive gear 25 that meshes with the external tooth gear 26 fixed to the rotating shaft 7 of the paper ejection roller 181a by the fixing pin 7a. It is rotatably supported.

In the drive device 30 shown in FIG. 7, the first drive transmission path R1 which is one of the two drive transmission paths for transmitting the drive force of the motor 21 to the paper ejection roller 181a is an external tooth which is a drive transmission member. It is composed of a gear 27 and an external tooth gear 28. Further, the second drive transmission path R2, which is the other of the two drive transmission paths, is composed of the internal tooth gear 23 and the external tooth gear 24, which are drive transmission members.

The direction of the thrust acting from the hasba gear 21a to the idler gear 22 is determined by the rotation direction of the motor 21 and the twisting direction of the hasba gear 21a. In FIG. 7, since the twisting direction of the hasba gear 11a is to the left, by driving the motor 21 in the clockwise direction (CW), a thrust force acts on the idler gear 22 from the hasva gear 21a to the external tooth gear 27 side. Therefore, the idler gear 22 moves toward the external tooth gear 27 in the thrust direction, the drive connecting claw 22b is fitted into the drive connecting hole 27a, and the idler gear 22 and the external tooth gear 27 engage with each other, so that the idler gear 22 becomes the external tooth. Drive the gear 27. The external tooth gear 27 drives an external tooth gear 28 rotatably attached to the fixed shaft S2. Then, the drive gear 25 arranged coaxially with the external tooth gear 28 drives the external tooth gear 26 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 rotates in the same direction as the rotation direction of the motor 21 by the driving force transmitted from the first drive transmission path R1.

On the other hand, by driving the motor 21 in the counterclockwise direction (CCW), a thrust force acts on the idler gear 22 from the hasba gear 21a to the axial internal tooth gear 23 side. Therefore, the idler gear 22 moves toward the internal gear 23 in the thrust direction, the drive connecting claw 22a fits into the drive connecting hole 23a, and the idler gear 22 and the internal gear 23 engage with each other, so that the idler gear 22 has internal teeth. Drives the gear 23. The internal gear 23 drives the external gear 24 rotatably supported by the fixed shaft S2. Then, the drive gear 25 arranged coaxially with the external tooth gear 24 drives the external tooth gear 26 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 is in the direction opposite to the rotating direction of the motor 21 due to the driving force transmitted from the second drive transmission path R2, and is the external tooth gear 27 / external tooth. It is driven at a rotation speed different from the reduction ratio of the gear 28.

By configuring the drive transmission path using internal gears as in the drive device 30 according to this configuration example, the meshing portion with the external gear can be covered with the internal gear, and the meshing portion can be used. The generated noise can be shielded by the internal gear. Further, the meshing rate between the external tooth gear and the internal tooth gear can be increased as compared with the meshing between the external tooth gears, and the generation of noise and vibration can be suppressed. This makes it possible to improve the quietness of the drive device 30. Therefore, as the drive transmission path using the internal gear, it is preferable to use the drive transmission path which is frequently used and has a long usage time.

[Configuration Example 4]
FIG. 8 is a schematic cross-sectional view of the drive device 30 according to the configuration example 4. As shown in FIG. 8, in the drive device 30, a motor 31 which is a drive source capable of forward / reverse rotation is attached to a side plate 133. A Hassuba gear 31a is provided on the output shaft of the motor 31, and the internal tooth Hassuba gear portion 32a of the idler gear 32 rotatably supported on the fixed shaft S3 fixed to the side plate 131 and the side plate 133, and the Hassuba gear 31a. Are in mesh. Further, the idler gear 32 is concentrically provided with an external tooth hasbar gear portion 32b, and is an idler gear 33 rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and an external tooth hasba gear. It is in mesh with the portion 32b. The idler gear 33 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 33a and a plurality of drive connecting claws 33b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 37 rotatably supported by the fixed shaft S1 facing the idler gear 33, a plurality of drive connecting holes 37a into which a plurality of drive connecting claws 33a are fitted are formed on the rotation trajectory of the drive connecting claws 33a. It is formed. Then, the idler gear 33 moves toward the external tooth gear 37 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 33a fits into the drive connecting hole 37a, so that the idler gear 33 and the external tooth gear 37 engage with each other. It is possible. Further, on the side surface of the pulley 34 rotatably supported by the fixed shaft S1 facing the idler gear 33, a plurality of drive connecting holes 34a into which a plurality of drive connecting claws 33b are fitted are formed on the rotation trajectory of the drive connecting claws 33b. It is formed. Then, the idler gear 33 moves to the axial pulley 34 side while rotating on the fixed shaft S1, and the drive connecting claw 33b fits into the drive connecting hole 34a, so that the idler gear 33 and the pulley 34 can be engaged with each other. There is.

The fixed shaft S2 is fixed to the side plate 131 and the side plate 132 at a position displaced from the fixed shaft S1 to the paper ejection roller 181a side in the radial direction, and the rotating shaft 7 of the paper ejection roller 181a is provided on the side plate 132. It is rotatably supported by the bearing 132a. A pulley 36 that stretches the timing belt 35 together with the pulley 34 is rotatably supported on the fixed shaft S2. Further, the external tooth gear 38 that meshes with the external tooth gear 37 coaxially with the pulley 36 and the drive gear 39 that meshes with the external tooth gear 40 fixed to the rotating shaft 7 of the paper ejection roller 181a by the fixing pin 7a are rotatable. Is supported by.

In the drive device 30 shown in FIG. 8, the first drive transmission path R1 which is one of the two drive transmission paths for transmitting the drive force of the motor 31 to the paper ejection roller 181a is the pulley 34 which is a drive transmission member. It is composed of a timing belt 35 and a pulley 36. Further, the second drive transmission path R2, which is the other of the two drive transmission paths, is composed of the external tooth gear 37 and the external tooth gear 38, which are drive transmission members.

The motor 31 drives the idler gear 33 via the internal tooth hasbar gear portion 32a and the external tooth hasba gear portion 32b of the idler gear 32. Here, the direction of the thrust acting from the external tooth hasbar gear portion 32b to the idler gear 33 is determined by the rotation direction of the idler gear 32 and the twisting direction of the external tooth hasbar gear portion 32b. In FIG. 8, by driving the motor 31 in the counterclockwise direction (CCW), the idler gear 32 rotates in the counterclockwise direction via the hasba gear 31a, and the idler gear 33 is out of the axial direction from the external tooth hasba gear portion 32b. A thrust force acts in the direction of the tooth gear 37. Therefore, the idler gear 33 moves toward the external tooth gear 37 in the thrust direction, the drive connecting claw 33a fits into the drive connecting hole 37a, and the idler gear 33 and the external tooth gear 37 engage with each other, so that the idler gear 33 becomes the external tooth. Drives the gear 37. The external tooth gear 37 drives an external tooth gear 38 rotatably attached to the fixed shaft S2. Then, the drive gear 39 arranged coaxially with the external tooth gear 38 drives the external tooth gear 40 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 rotates in the direction opposite to the rotation direction of the motor 31 due to the driving force transmitted from the second drive transmission path R2.

On the other hand, in FIG. 8, by driving the motor 31 in the clockwise direction (CW), the idler gear 32 rotates in the clockwise direction via the hasba gear 31a, and the idler gear 33 has an axial pulley from the external tooth hasba gear portion 32b. Thrust force acts on the 34 side. Therefore, the idler gear 33 moves toward the pulley 34 in the thrust direction, the drive connecting claw 33b fits into the drive connecting hole 34a, and the idler gear 33 and the pulley 34 engage with each other, so that the idler gear 33 drives the pulley 34. The pulley 34 drives the pulley 36 rotatably attached to the fixed shaft S2 via the timing belt 35. Then, the drive gear 39 arranged coaxially with the pulley 36 drives the external tooth gear 40 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 has the paper ejection roller 181a in the same direction as the rotation direction of the motor 31 due to the driving force transmitted from the first drive transmission path R1, and the external tooth gear. It is driven at a rotation speed different from the reduction ratio of the 37 / external tooth gear 38.

Further, the rotation direction of the motor 31 is changed by making the number of drive transmission members in the first drive transmission path R1 and the second drive transmission path R2 odd and even between the fixed shaft S1 and the fixed shaft S2. However, only the reduction ratio can be changed without changing the rotation direction of the paper ejection roller 181a.

Further, the hasba gear 31a of the motor 31 does not directly mesh with the idler gear 33 which is an external tooth gear, but meshes with the internal tooth hasva gear portion 32a of the idler gear 32, via the internal tooth hasba gear portion 32a and the external tooth hasva gear portion 32b. The drive is transmitted to the idler gear 33. As a result, the root of the hasba gear 31a can be meshed with the internal tooth hasba gear portion 32a, and the rotation accuracy can be improved and the noise can be reduced.

In the present embodiment, the configuration in which the paper ejection roller 181a is rotationally driven by the drive device 30 as the driven body has been described, but the driven body is not limited to the paper ejection roller 181a. For example, in order to form an image on both sides of the recording paper P, the double-sided roller 183 that inverts the front and back of the recording paper P and conveys the refeeding path 170 is used as the driven body, and the driving device of each of the above-described configuration examples is used. A configuration in which the rotation is driven by 30 can also be adopted.

[Embodiment 2]
Hereinafter, as an image forming apparatus to which the present invention is applied, another embodiment of an electrophotographic printer (hereinafter, simply referred to as a printer) will be described. Since the basic configuration of the printer according to the present embodiment is the same as the configuration of the printer according to the first embodiment, the description thereof will be omitted.

In the image forming apparatus, the paper is conveyed by a plurality of rollers, and the paper feed speed of the rollers is associated with each other so that the paper is not pulled or over-fed between the rollers. The image forming apparatus corresponding to various paper thicknesses finely adjusts the paper feed rate ratio between the rollers depending on the paper type because the transferability / fixability of the image changes depending on the thickness of the paper. Therefore, conventionally, for the rollers for which the paper feed rate ratio of the rollers is desired to be changed, the drive sources are separately provided. However, although the speed fine adjustment between the rollers can be easily changed by changing the speed of the motors, the increase in the number of motors causes problems of cost increase, drive noise increase, space, and power consumption. Therefore, in a drive device having at least two drive trains and a plurality of rollers from one motor, a "drive train at the time of forward rotation" and a "drive train at the time of reverse rotation" of the motor are provided, and deceleration of each drive train is provided. The paper feed speed ratio between the rollers is changed by finely adjusting the ratio. As a result, it is possible to solve the problems of cost increase, drive noise increase, space, and power consumption that may occur due to the increase in the number of motors as described above.

Specifically, the motor output gear is made into a Hasba gear, and the idler gear that meshes with the motor output gear is made movable in the axial direction. Then, by changing the rotation direction of the motor, the direction of the thrust force acting on the idler gear from the motor output gear, which is a hasba gear, changes, so that the shaft joint (coupling) of the idler gear can be selected. Since the rotation direction of the motor is changed, the rotation direction from the shaft joint to the roller is different, such as "change the number of gears", "gear and belt", or "external tooth gear and internal tooth gear". Two drive transmission paths are provided. Moreover, by changing the reduction ratio, the rotation direction of the rollers can be made the same and the speed can be finely adjusted.

[Configuration Example 5]
FIG. 9 is a diagram showing a drive transmission configuration of the drive device 30 according to the configuration example 5. The drive device 30 according to the configuration example 5 includes a motor 1 which is a drive source capable of forward / reverse rotation, and the motor 1 is attached to the side plate 131. The output shaft of the motor 41 is provided with a hasba gear 41a on the left in the twisting direction, and the hasva gear 41a and the idler gear 42 are in mesh with each other. The idler gear 42 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 42a and a plurality of drive connecting claws 42b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 48 rotatably supported by the fixed shaft S1 facing the idler gear 42, a plurality of drive connecting holes 48a into which a plurality of drive connecting claws 42a are fitted are formed on the rotation trajectory of the drive connecting claws 42a. It is formed. Then, the idler gear 42 moves toward the external tooth gear 48 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 42a fits into the drive connecting hole 48a, so that the idler gear 42 and the external tooth gear 48 engage with each other. It is possible. Further, on the side surface of the pulley 43 rotatably supported by the fixed shaft S1 facing the idler gear 42, a plurality of drive connecting holes 43a into which a plurality of drive connecting claws 42b are fitted are formed on the rotation trajectory of the drive connecting claws 42b. It is formed. Then, the idler gear 42 moves to the axial pulley 43 side while rotating on the fixed shaft S1, and the drive connecting claw 42b fits into the drive connecting hole 43a, so that the idler gear 42 and the pulley 43 can be engaged with each other. There is.

The fixed shaft S2 is fixed to the side plate 131 and the side plate 132 at a position displaced to the resist roller 143a side in the radial direction with respect to the fixed shaft S1, and the rotation shaft of the resist roller 143a is provided on the side plate 132. It is rotatably supported. A pulley 45 that stretches the timing belt 44 together with the pulley 43 is rotatably supported on the fixed shaft S2, and a drive gear 46 that meshes with the external tooth gear 48 coaxially with the pulley 45 is rotatably supported. There is. The drive gear 46 meshes with an external tooth gear 47 fixed to the rotating shaft 49 of the resist roller 143a by a fixing pin 49a.

In the drive device 30 shown in FIG. 9, the first drive transmission path Rs1 which is one of the two drive transmission paths for transmitting the drive force of the motor 41 to the resist roller 143a is a pulley 43 which is a drive transmission member. It is composed of a timing belt 44 and a pulley 45. Further, the second drive transmission path Rs2, which is the other of the two drive transmission paths, is composed of the external tooth gear 48 and the drive gear 46, which are drive transmission members.

Further, the hasba gear 41a meshes with the idler gear 52. The idler gear 52 is rotatably supported by a fixed shaft t1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 52a and a plurality of drive connecting claws 52b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 58 rotatably supported by the fixed shaft t1 facing the idler gear 52, a plurality of drive connecting holes 58a into which a plurality of drive connecting claws 52a are fitted are formed on the rotation trajectory of the drive connecting claws 52a. It is formed. Then, the idler gear 52 moves toward the external tooth gear 58 in the axial direction while rotating on the fixed shaft t1, and the drive connecting claw 52a fits into the drive connecting hole 58a, so that the idler gear 52 and the external tooth gear 58 engage with each other. It is possible. Further, on the side surface of the pulley 53 rotatably supported by the fixed shaft t1 facing the idler gear 52, a plurality of drive connecting holes 53a into which a plurality of drive connecting claws 52b are fitted are formed on the rotation trajectory of the drive connecting claws 52b. It is formed. Then, the idler gear 52 moves to the axial pulley 53 side while rotating on the fixed shaft t1, and the drive connecting claw 52b fits into the drive connecting hole 53a, so that the idler gear 52 and the pulley 53 can be engaged with each other. There is.

The fixed shaft t2 is fixed to the side plate 131 and the side plate 132 at a position shifted to the fixing roller 145 side in the radial direction with respect to the fixed shaft t1, and the rotation shaft of the fixing roller 145 is provided on the side plate 132. It is rotatably supported. A pulley 55 that stretches the timing belt 54 together with the pulley 53 is rotatably supported on the fixed shaft t2, and a drive gear 56 that meshes with the external tooth gear 58 coaxially with the pulley 55 is rotatably supported. There is. The drive gear 56 meshes with the external tooth gear 57 fixed to the rotating shaft 59 of the fixing roller 145 by the fixing pin 59a.

In the drive device 30 shown in FIG. 9, the first drive transmission path Rt1 which is one of the two drive transmission paths for transmitting the drive force of the motor 41 to the fixing roller 145 is the pulley 53 which is a drive transmission member. It is composed of a timing belt 54 and a pulley 55. Further, the second drive transmission path Rt2, which is the other of the two drive transmission paths, is composed of the external tooth gear 58 and the drive gear 56, which are drive transmission members.

In FIG. 9, by driving the motor 41 in the clockwise direction (CW), a thrust force acts on the idler gear 42 from the hasba gear 41a to the axial pulley 43 side. Therefore, the idler gear 42 moves toward the pulley 43 in the thrust direction, the drive connecting claw 42b fits into the drive connecting hole 43a, and the idler gear 42 and the pulley 43 engage with each other, so that the idler gear 42 drives the pulley 43. The pulley 43 drives the pulley 45 rotatably attached to the fixed shaft S2 via the timing belt 44. Then, the drive gear 46 arranged coaxially with the pulley 45 drives the external tooth gear 47 provided on the rotating shaft 49 of the resist roller 143a. As a result, the resist roller 143a provided on the rotating shaft 49 rotates in the same direction as the rotation direction of the motor 41 by the driving force transmitted from the first drive transmission path Rs1.

Further, by driving the motor 41 in the clockwise rotation direction, a thrust force acts on the idler gear 52 from the hasba gear 41a to the axial pulley 53 side. Therefore, the idler gear 52 moves toward the pulley 53 in the thrust direction, the drive connecting claw 52b fits into the drive connecting hole 53a, and the idler gear 52 and the pulley 53 engage with each other, so that the idler gear 52 drives the pulley 53. The pulley 53 drives the pulley 55 rotatably attached to the fixed shaft t2 via the timing belt 54. Then, the drive gear 56 arranged coaxially with the pulley 55 drives the external tooth gear 57 provided on the rotating shaft 59 of the fixing roller 145. As a result, the fixing roller 145 provided on the rotating shaft 59 rotates in the same direction as the rotation direction of the motor 41 by the driving force transmitted from the first drive transmission path Rt1.

On the other hand, in FIG. 9, by driving the motor 41 in the counterclockwise direction (CCW), a thrust force acts on the idler gear 42 from the hasba gear 41a to the axial external tooth gear 48 side. Therefore, the idler gear 42 moves toward the external tooth gear 48 in the thrust direction, the drive connecting claw 42a fits into the drive connecting hole 48a, and the idler gear 42 and the external tooth gear 48 engage with each other, so that the idler gear 42 becomes the external tooth. Drives the gear 48. Then, the external tooth gear 48 drives the drive gear 46 arranged coaxially with the pulley 45, so that the external tooth gear 47 provided on the rotating shaft 49 of the resist roller 143a is driven by the drive gear 46. .. As a result, the resist roller 143a provided on the rotating shaft 49 has a reduction ratio of the pulley 43 / pulley 45 in the direction opposite to the rotation direction of the motor 41 due to the driving force transmitted from the second drive transmission path Rs2. It is driven at a different rotation speed from.

Further, by driving the motor 41 in the counterclockwise direction, a thrust force acts on the idler gear 52 from the hasba gear 41a to the axial external tooth gear 58 side. Therefore, the idler gear 52 moves toward the external tooth gear 58 in the thrust direction, the drive connecting claw 52a is fitted into the drive connecting hole 58a, and the idler gear 52 and the external tooth gear 58 are engaged with each other, so that the idler gear 52 becomes the external tooth. Drive the gear 58. Then, the external tooth gear 58 drives the drive gear 56 arranged coaxially with the pulley 55, so that the external tooth gear 57 provided on the rotating shaft 59 of the fixing roller 145 is driven by the drive gear 56. .. As a result, the fixing roller 145 provided on the rotating shaft 59 has a reduction ratio of the pulley 53 / pulley 55 in the direction opposite to the rotating direction of the motor 41 due to the driving force transmitted from the second drive transmission path Rt2. It is driven at a different rotation speed from.

In the drive device 30 according to this configuration example, as described above, the reduction ratio is determined by the drive transmission path when the rotation direction of the motor 41 is clockwise and the drive transmission path when the rotation direction is counterclockwise. Make it different. As a result, the ratio of the rotation speeds of the resist roller 143a and the fixing roller 145 can be changed depending on whether the rotation direction of the motor 41 is clockwise or counterclockwise. Therefore, the speeds of the resist roller 143a and the fixing roller 145 can be finely adjusted with a single motor 41 without providing two motors corresponding to the resist roller 143a and the fixing roller 145, respectively, and the cost can be reduced. Can be planned. It is desirable that the difference in deceleration ratio between the resist roller 143a and the fixing roller 145 is 3 [%] or less. This makes it possible to fine-tune the speed between the two rollers at 3 [%] or less.

[Configuration Example 6]
FIG. 10 is a diagram showing a drive transmission configuration of the drive device 30 according to the configuration example 6. The drive device 30 according to the configuration example 6 includes a motor 61 which is a drive source capable of forward / reverse rotation, and the motor 61 is attached to the side plate 131. The output shaft of the motor 31 is provided with a hasba gear 61a on the left in the twisting direction, and the hasva gear 61a and the idler gear 62 are in mesh with each other. The idler gear 62 is rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 62a and drive connecting claws 62b are provided on both side surfaces in the axial direction. On the side surface of the pulley 68 rotatably supported by the fixed shaft S1 facing the idler gear 62, a plurality of drive connecting holes 68a into which a plurality of drive connecting claws 62a are fitted are formed on the rotation trajectory of the drive connecting claws 62a. ing. Then, the idler gear 62 moves toward the pulley 68 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 62a fits into the drive connecting hole 68a, so that the idler gear 62 and the pulley 68 can be engaged with each other. There is. Further, on the side surface of the external tooth gear 63 rotatably supported by the fixed shaft S1 facing the idler gear 62, a plurality of drive connecting holes 63a into which a plurality of drive connecting claws 62b are fitted are provided in the rotation trajectory of the drive connecting claw 62b. Formed on top. Then, the idler gear 62 moves toward the external tooth gear 63 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 62b fits into the drive connecting hole 63a, so that the idler gear 62 and the external tooth gear 63 engage with each other. It is possible.

The fixed shaft S2 and the fixed shaft S3 are fixed to the side plate 131 and the side plate 132 at a position shifted to the resist roller 143a side in the radial direction with respect to the fixed shaft S1, and the rotating shaft of the resist roller 143a is fixed to the side plate 132. It is rotatably supported by the provided bearing 132a. A pulley 70 for tensioning the timing belt 69 together with the pulley 68 is rotatably supported on the fixed shaft S2. Further, the external tooth gear 64 that meshes with the external tooth gear 63 coaxially with the pulley 70 and the external tooth gear 65 located between the pulley 70 and the external tooth gear 64 in the axial direction are rotatable on the fixed shaft S2. Is supported by. A drive gear 66 that meshes with the external tooth gear 65 is rotatably supported on the fixed shaft S3, and the drive gear 66 is further fixed to the rotating shaft 49 of the resist roller 143a by a fixing pin 49a. It meshes with 67.

In the drive device 30 shown in FIG. 10, the first drive transmission path Rs1 which is one of the two drive transmission paths for transmitting the drive force of the motor 61 to the resist roller 143a is an external tooth gear which is a drive transmission member. It is composed of 63 and an external tooth gear 64. Further, the second drive transmission path Rs2, which is the other of the two drive transmission paths, is composed of a pulley 68, a timing belt 69, and a pulley 70, which are drive transmission members.

Further, the hasba gear 61a and the idler gear 72 are in mesh with each other. The idler gear 72 is rotatably supported by a fixed shaft t1 fixed to the side plate 131 and the side plate 132, and a plurality of drive connecting claws 72a and drive connecting claws 72b are provided on both side surfaces in the axial direction. On the side surface of the external tooth gear 78 rotatably supported by the fixed shaft t1 facing the idler gear 72, a plurality of drive connecting holes 78a into which a plurality of drive connecting claws 72a are fitted are provided on the rotation trajectory of the drive connecting claws 72a. It is formed. Then, the idler gear 72 moves to the axial pulley 78 side while rotating on the fixed shaft t1, and the drive connecting claw 72a fits into the drive connecting hole 78a so that the idler gear 72 and the external tooth gear 78 can be engaged with each other. It has become. Further, on the side surface of the external tooth gear 73 rotatably supported by the fixed shaft t1 facing the idler gear 72, a plurality of drive connecting holes 73a into which a plurality of drive connecting claws 72b are fitted are provided in the rotation trajectory of the drive connecting claws 72b. Formed on top. Then, the idler gear 72 moves toward the external tooth gear 73 in the axial direction while rotating on the fixed shaft t1, and the drive connecting claw 72b fits into the drive connecting hole 73a, so that the idler gear 72 and the external tooth gear 73 engage with each other. It is possible.

The fixed shaft t2 and the fixed shaft t3 are fixed to the side plate 131 and the side plate 132 at a position shifted to the fixing roller 145 side in the radial direction with respect to the fixed shaft S1, and the rotating shaft of the fixing roller 145 is fixed to the side plate 132. It is rotatably supported by the provided bearing 132b. An external tooth gear 74 that meshes with the external tooth gear 73 is rotatably supported on the fixed shaft t3. An external tooth gear 75 that meshes with the external tooth gear 74 is rotatably supported on the fixed shaft t2, and a drive gear 76 that meshes with the external tooth gear 78 coaxially with the external tooth gear 75 is rotatably supported. .. The drive gear 76 also meshes with the external tooth gear 77 fixed to the rotating shaft 59 of the fixing roller 145 by the fixing pin 59a.

In the drive device 30 shown in FIG. 10, the first drive transmission path Rt1 which is one of the two drive transmission paths for transmitting the drive force of the motor 61 to the fixing roller 145 is an external tooth gear which is a drive transmission member. It is composed of 73, an external tooth gear 74, and an external tooth gear 75. Further, the second drive transmission path Rt2, which is the other of the two drive transmission paths, is composed of the external tooth gear 78 and the drive gear 76, which are drive transmission members.

In FIG. 10, by driving the motor 61 in the clockwise direction (CW), a thrust force acts on the idler gear 62 from the hasba gear 61a to the axial external tooth gear 63 side. Therefore, the idler gear 62 moves toward the external tooth gear 63 in the thrust direction, the drive connecting claw 62b is fitted into the drive connecting hole 63a, and the idler gear 62 and the external tooth gear 63 are engaged with each other, so that the idler gear 62 becomes the external tooth. Drive the gear 63. The pulley 43 drives the pulley 45 rotatably attached to the fixed shaft S2 via the timing belt 44. Then, the drive gear 46 arranged coaxially with the pulley 45 drives the external tooth gear 47 provided on the rotating shaft 49 of the resist roller 143a. The external tooth gear 63 drives an external tooth gear 64 rotatably attached to the fixed shaft S2. Then, the drive gear 66 is driven via the external tooth gear 65 arranged coaxially with the external tooth gear 64, and the drive gear 66 drives the external tooth gear 67 provided on the rotating shaft 49 of the resist roller 143a. .. As a result, the resist roller 143a provided on the rotating shaft 49 rotates in the same direction as the rotation direction of the motor 61 by the driving force transmitted from the first drive transmission path Rs1.

Further, by driving the motor 61 in the clockwise rotation direction, a thrust force acts on the idler gear 72 from the hasba gear 61a to the axial external tooth gear 73 side. Therefore, the idler gear 72 moves toward the external tooth gear 73 in the thrust direction, the drive connecting claw 72b is fitted into the drive connecting hole 73a, and the idler gear 72 and the external tooth gear 73 engage with each other, so that the idler gear 72 has the external tooth. Drives the gear 73. The pulley 53 drives the pulley 55 rotatably attached to the fixed shaft t2 via the timing belt 54. Then, the drive gear 56 arranged coaxially with the pulley 55 drives the external tooth gear 57 provided on the rotating shaft 59 of the fixing roller 145. The idler gear 72 moves to the external tooth gear 73 side, the drive connecting claw 72b fits into the drive connecting hole 73a, and the idler gear 72 and the external tooth gear 73 engage with each other, whereby the idler gear 72 drives the external tooth gear 73. .. The external tooth gear 73 drives the external tooth gear 75 rotatably attached to the fixed shaft t2 via the external tooth gear 74 rotatably attached to the fixed shaft t3. Then, the drive gear 76 arranged coaxially with the external tooth gear 75 is driven, and the drive gear 76 drives the external tooth gear 77 provided on the rotating shaft 59 of the fixing roller 145. As a result, the fixing roller 145 provided on the rotating shaft 59 rotates in the same direction as the rotation direction of the motor 61 by the driving force transmitted from the first drive transmission path Rt1.

On the other hand, in FIG. 10, by driving the motor 61 in the counterclockwise direction (CCW), a thrust force acts on the idler gear 62 from the hasba gear 61a to the axial pulley 68 side. Therefore, the idler gear 62 moves toward the pulley 68 in the thrust direction, the drive connecting claw 62a fits into the drive connecting hole 68a, and the idler gear 62 and the pulley 68 engage with each other, so that the idler gear 62 drives the pulley 68. The pulley 68 drives a pulley 70 rotatably attached to the fixed shaft S2 via a timing belt 69. Then, the drive gear 66 is driven via the external tooth gear 65 arranged coaxially with the pulley 70, and the drive gear 66 drives the external tooth gear 67 provided on the rotating shaft 49 of the resist roller 143a. As a result, the resist roller 143a provided on the rotating shaft 49 is in the direction opposite to the rotating direction of the motor 61 due to the driving force transmitted from the second drive transmission path Rs2, and is the external tooth gear 63 / external tooth gear. It is driven at a rotation speed different from the reduction ratio of 65.

Further, by driving the motor 61 in the counterclockwise direction, a thrust force acts on the idler gear 72 from the hasba gear 61a to the axial external tooth gear 78 side. Therefore, the idler gear 72 moves toward the external tooth gear 78 in the thrust direction, the drive connecting claw 72a is fitted into the drive connecting hole 78a, and the idler gear 72 and the external tooth gear 78 engage with each other, so that the idler gear 72 has the external tooth. Drive the gear 78. The external tooth gear 78 drives a drive gear 76 rotatably attached to the fixed shaft t2. Then, the drive gear 76 drives the external tooth gear 77 provided on the rotating shaft 59 of the fixing roller 145. As a result, the fixing roller 145 provided on the rotating shaft 59 is in the direction opposite to the rotating direction of the motor 61 due to the driving force transmitted from the second drive transmission path Rt2, and is the external tooth gear 73 / external tooth gear. It is driven at a rotation speed different from the reduction ratio of 75.

Between the fixed shaft S1 and the fixed shaft S2, the number of drive transmission members such as gears, pulleys, and timing belts differs between the first drive transmission path Rs1 and the second drive transmission path Rs2 between an even number and an odd number. Therefore, even if the rotation direction of the motor 61 is changed, only the reduction ratio can be changed without changing the rotation direction of the paper ejection roller 181a. Further, between the fixed shaft t1 and the fixed shaft t2, the number of drive transmission members differs between the first drive transmission path Rt1 and the second drive transmission path Rt2 between odd and even numbers. Therefore, even if the rotation direction of the motor 61 is changed, only the reduction ratio can be changed without changing the rotation direction of the fixing roller 145. Therefore, in the drive device 30 according to the present configuration example, even if the rotation direction of the motor 61 is changed, the rotation directions of the resist roller 143a and the fixing roller 145 do not change, and only the reduction ratio can be finely adjusted.

[Configuration Example 7]
FIG. 11 is a diagram showing a drive transmission configuration of the drive device 30 according to the configuration example 7. In the drive device 30 according to the configuration example 7, a motor 81, which is a drive source capable of forward / reverse rotation, is attached to a side plate 133. A motor gear 81a is provided on the output shaft of the motor 81, and the internal tooth hasbar gear portion 82a of the idler gear 82 rotatably supported by the fixed shaft S3 fixed to the side plate 131 and the side plate 133, and the motor gear 81a. Are in mesh. Further, the idler gear 82 is concentrically provided with an external tooth hasbar gear portion 82b, and is an idler gear 83 rotatably supported by a fixed shaft S1 fixed to the side plate 131 and the side plate 132, and an external tooth hasba gear. It is in mesh with the portion 82b.

The idler gear 83 is provided with a plurality of drive connecting claws 83a and a plurality of drive connecting claws 83b on both side surfaces in the axial direction. On the side surface of the external tooth gear 84 rotatably supported by the fixed shaft S1 facing the idler gear 83, a plurality of drive connecting holes 84a into which a plurality of drive connecting claws 83a are fitted are formed on the rotation trajectory of the drive connecting claws 83a. It is formed. Then, the idler gear 83 moves toward the external tooth gear 84 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 83a fits into the drive connecting hole 84a, so that the idler gear 83 and the external tooth gear 84 engage with each other. It is possible. Further, on the side surface of the pulley 86 rotatably supported by the fixed shaft S1 facing the idler gear 83, a plurality of drive connecting holes 86a into which a plurality of drive connecting claws 83b are fitted are provided on the rotation trajectory of the drive connecting claws 83b. It is formed. Then, the idler gear 83 moves toward the pulley 86 in the axial direction while rotating on the fixed shaft S1, and the drive connecting claw 83b fits into the drive connecting hole 86a, so that the idler gear 83 and the pulley 86 can be engaged with each other. There is.

The fixed shaft S2 is fixed to the side plate 131 and the side plate 132 at a position displaced from the fixed shaft S1 to the paper ejection roller 181a side in the radial direction, and the rotating shaft 7 of the paper ejection roller 181a is provided on the side plate 132. It is rotatably supported by the bearing 132a. A pulley 88 that stretches the timing belt 87 together with the pulley 86 is rotatably supported on the fixed shaft S2, and a drive gear 85 that meshes with the external tooth gear 84 coaxially with the pulley 88 is rotatably supported. There is. The drive gear 85 also meshes with the external tooth gear 89 fixed to the rotating shaft 7 of the paper ejection roller 181a by a fixing pin 7a.

In the drive device 30 shown in FIG. 11, the first drive transmission path Rs1 which is one of the two drive transmission paths for transmitting the drive force of the motor 81 to the paper ejection roller 181a is the pulley 86 which is a drive transmission member. It is composed of a timing belt 87 and a pulley 88. Further, the second drive transmission path Rs2, which is the other of the two drive transmission paths, is composed of the external tooth gear 84 and the drive gear 85, which are drive transmission members.

Further, the external tooth hasbar gear portion 82b of the idler gear 82 meshes with the idler gear 93 which is the idler gear 93. The idler gear 93 is provided with a plurality of drive connecting claws 93a and a plurality of drive connecting claws 93b on both side surfaces in the axial direction. On the side surface of the external tooth gear 94 rotatably supported by the fixed shaft t1 facing the idler gear 93, a plurality of drive connecting holes 94a into which a plurality of drive connecting claws 93a are fitted are provided on the rotation trajectory of the drive connecting claws 93a. It is formed. Then, the idler gear 93 moves to the axial external tooth gear 94 side while rotating on the fixed shaft t1, and the drive connecting claw 93a fits into the drive connecting hole 94a, so that the idler gear 93 and the external tooth gear 94 engage with each other. It is possible. Further, on the side surface of the pulley 96 rotatably supported by the fixed shaft t1 facing the idler gear 93, a plurality of drive connecting holes 96a into which a plurality of drive connecting claws 93b are fitted are provided on the rotation trajectory of the drive connecting claws 93b. It is formed. Then, the idler gear 93 moves toward the pulley 96 in the axial direction while rotating on the fixed shaft t1, and the drive connecting claw 93b fits into the drive connecting hole 96a, so that the idler gear 93 and the pulley 96 can be engaged with each other. There is.

The fixed shaft t2 is fixed to the side plate 131 and the side plate 132 at a position shifted to the fixing roller 145 side in the radial direction with respect to the fixed shaft t1, and the rotation shaft of the fixing roller 145 is provided on the side plate 132. It is rotatably supported. A pulley 98 that stretches a timing belt 97 together with the pulley 96 is rotatably supported on the fixed shaft t2, and a drive gear 95 that meshes with the external tooth gear 94 coaxially with the pulley 98 is rotatably supported. There is. The drive gear 95 also meshes with the external tooth gear 99 fixed to the rotating shaft 59 of the fixing roller 145 by the fixing pin 59a.

In the drive device 30 shown in FIG. 11, the first drive transmission path Rt1 which is one of the two drive transmission paths for transmitting the drive force of the motor 81 to the fixing roller 145 is the pulley 96 which is a drive transmission member. It is composed of a timing belt 97 and a pulley 98. Further, the second drive transmission path Rt2, which is the other of the two drive transmission paths, is composed of the external tooth gear 94 and the drive gear 95, which are drive transmission members.

The motor 81 drives the idler gear 83 via the internal tooth hasbar gear portion 82a and the external tooth hasbar gear portion 82b of the idler gear 82. Here, the direction of the thrust acting from the external tooth hasbar gear portion 82b to the idler gear 83 is determined by the rotation direction of the idler gear 82 and the twisting direction of the external tooth hasbar gear portion 82b. In FIG. 8, by driving the motor 81 in the clockwise direction (CW), the idler gear 82 rotates in the clockwise direction via the motor gear 81a, and the idler gear 83 is on the axial pulley 86 side from the external tooth hasbar gear portion 82b. Thrust force works in the direction of. Therefore, the idler gear 83 moves toward the pulley 86 in the thrust direction, the drive connecting claw 83b fits into the drive connecting hole 86a, and the idler gear 83 and the pulley 86 engage with each other, so that the idler gear 83 drives the pulley 86. The pulley 86 drives the pulley 88 rotatably attached to the fixed shaft S2 via the timing belt 87. Then, the drive gear 85 arranged coaxially with the pulley 88 drives the external tooth gear 89 provided on the rotating shaft 7 of the paper ejection roller 181a. As a result, the paper ejection roller 181a provided on the rotating shaft 7 rotates in the same direction as the rotation direction of the motor 81 by the driving force transmitted from the first drive transmission path Rs1.

Further, the idler gear 82 meshes with the idler gear 93. By driving the motor 81 in the clockwise direction, the idler gear 82 rotates in the clockwise direction via the motor gear 81a, and a thrust force acts on the idler gear 93 from the external tooth hasbar gear portion 82b toward the axial pulley 96 side. .. Therefore, the idler gear 93 moves toward the pulley 96 in the thrust direction, the drive connecting claw 93b is fitted into the drive connecting hole 96a, and the idler gear 93 and the pulley 96 engage with each other, so that the idler gear 93 drives the pulley 96. The pulley 96 drives the pulley 98 rotatably attached to the fixed shaft t2 via a timing belt 97. Then, the drive gear 95 arranged coaxially with the pulley 98 drives the external tooth gear 99 provided on the rotating shaft 59 of the fixing roller 145. As a result, the fixing roller 145 provided on the rotating shaft 59 rotates in the same direction as the rotation direction of the motor 81 by the driving force transmitted from the first drive transmission path Rt1.

On the other hand, in FIG. 11, by driving the motor 81 in the counterclockwise direction (CCW), the idler gear 82 rotates in the counterclockwise direction via the motor gear 81a, and the idler gear 83 has a shaft from the external tooth hasbar gear portion 82b. A thrust force acts in the direction of the external tooth gear 84 side. Therefore, the idler gear 83 moves toward the external tooth gear 84 in the thrust direction, the drive connecting claw 83a is fitted into the drive connecting hole 84a, and the idler gear 83 and the external tooth gear 84 engage with each other, so that the idler gear 83 becomes the external tooth. Drives the gear 84. Then, the external tooth gear 84 drives the drive gear 85 arranged coaxially with the pulley 88, so that the external tooth gear 89 provided on the rotating shaft 7 of the paper ejection roller 181a is driven by the drive gear 85. Tooth. As a result, the paper ejection roller 181a provided on the rotating shaft 7 is in the direction opposite to the rotating direction of the motor 81 due to the driving force transmitted from the second drive transmission path Rs2, and decelerates the pulley 86 / pulley 88. It is driven at a rotation speed different from the ratio.

Further, by rotating the idler gear 82 in the counterclockwise direction, a thrust force acts on the idler gear 93 in the direction from the external tooth hasbar gear portion 82b toward the external tooth gear 94 in the axial direction. Therefore, the idler gear 93 moves to the external tooth gear 94 side in the thrust direction, the drive connecting claw 93a is fitted into the drive connecting hole 94a, and the idler gear 93 and the external tooth gear 94 are engaged with each other, so that the idler gear 93 becomes the external tooth. Drives the gear 94. Then, the external tooth gear 94 drives the drive gear 95 arranged coaxially with the pulley 98, so that the external tooth gear 99 provided on the rotating shaft 59 of the fixing roller 145 is driven by the drive gear 95. .. As a result, the fixing roller 145 provided on the rotating shaft 59 has a reduction ratio of the pulley 96 / pulley 98 in the direction opposite to the rotating direction of the motor 81 due to the driving force transmitted from the second drive transmission path Rt2. It is driven at a different rotation speed from.

In the drive device 30 according to this configuration example, the motor gear 81a of the motor 81 does not directly mesh with the idler gears 83 and 93, which are external tooth gears, but meshes with the internal tooth toothbar gear portion 82a of the idler gear 82. Then, the drive is transmitted from the motor gear 81a to the idler gears 83 and 93 via the internal tooth hasbar gear portion 82a and the external tooth hasba gear portion 82b. As a result, the root of the motor gear 81a can be meshed with the internal tooth toothbar gear portion 82a, so that the rotation accuracy can be improved and the noise can be reduced.

What has been described above is an example, and has a unique effect in each of the following aspects.
(Aspect A)
For a drive source such as a motor 1 capable of forward rotation and reverse rotation, an input side rotating member such as a rotatable hasba gear 1a to which a rotational driving force is input from the drive source, and a driven body such as a paper ejection roller 181a. An output-side rotary member such as a rotatable external tooth gear 8 that outputs a rotary drive force, two systems of drive transmission paths for transmitting a rotary drive force from the input-side rotary member to the output-side rotary member, and the above. In a drive device such as a drive device 30 provided with a drive transmission path switching means for switching a drive transmission path from the input side rotating member to the output side rotating member, the drive transmission path switching means is used when the drive source rotates in the normal direction. And at the time of reversal, the drive transmission paths of the two systems move in different directions in the thrust direction, and the drive transmission path of one of the drive transmission paths of the two systems or the drive transmission path of the other system is used. It has a movable rotating member such as a rotatable idler gear 2 that transmits a rotational driving force from a source.
In (Aspect A), the input side rotation is performed by moving the moving rotation member in different directions in the thrust direction between the drive transmission paths of the two systems during normal rotation and reverse rotation of the drive source. The drive transmission path from the member to the output side rotating member can be switched. That is, the moving rotating body having a function of transmitting the rotational driving force from the driving source to each driving transmission path is also used as a member for selectively switching the driving transmission paths of the two systems. Therefore, in addition to the gear for transmitting the rotational driving force from the drive source to each drive transmission path, the one-way clutch is not provided as compared with the configuration in which the one-way clutch for selectively switching the two drive transmission paths is provided. The cost increase can be suppressed by that amount.
(Aspect B)
In (Aspect A), the moving rotating member has a toothbar gear portion, and by rotating the drive source in the normal direction, the moving rotating member moves toward one end side in the thrust direction, and one of the driving transmissions is transmitted. The drive is transmitted from the moving rotary member to the first drive transmission member by engaging with the first drive transmission member such as the pulley 3 provided in the path, and the drive source is reversed to cause the rotary drive transmission member. Moves toward the other end in the thrust direction and engages with a second drive transmission member such as an external tooth gear 9 provided in the other drive transmission path from the moving rotation member to the second drive transmission member. The drive is transmitted. According to this, as described in the above embodiment, by changing the rotation direction of the drive source, the direction of the force acting on the moving rotating member in the thrust direction changes, and the direction in which the moving rotating member moves in the thrust direction. Can be changed to switch the drive transmission path.
(Aspect C)
In (Aspect A) or (Aspect B), an internal gear such as an internal gear Hasba gear portion 32a that meshes with an output gear member such as a Hasba gear 31a provided on the output shaft of the drive source and an internal gear coaxially with the internal gear. It has an external toothed gear such as an external toothed gear portion 32b that is provided in the above and rotates integrally with the internal gear, and the moving rotating member and the external toothed gear mesh with each other. According to this, as described in the above-described embodiment, quietness can be enhanced.
(Aspect D)
In any one of (Aspect A) to (Aspect C), the drive transmission paths of the two systems include a drive transmission path in which the rotation directions of the input side rotating member and the output side rotating member are the same, and the input side. It is a drive transmission path in which the rotation directions of the rotating member and the output side rotating member are opposite to each other. According to this, as described in the above embodiment, the rotation direction of the driven body can be the same regardless of the rotation direction of the drive source.
(Aspect E)
In (Aspect A) to (Aspect D), one of the two drive transmission paths is configured to perform drive transmission using a belt member rotatably stretched by a plurality of pulleys. The other is configured so that drive transmission is performed by a gear train in which a plurality of gear members are meshed with each other. According to this, as described above, it is possible to make the rotation direction of the driven body the same regardless of the rotation direction of the drive source.
(Aspect F)
In (Aspect A) to (Aspect D), one of the two drive transmission paths has an even number of drive transmission members and the other has an odd number of drive transmission members. According to this, as described above, it is possible to make the rotation direction of the driven body the same regardless of the rotation direction of the drive source.
(Aspect G)
In (Aspect A) to (Aspect D), one of the two drive transmission paths is configured to perform drive transmission using an internal gear, and the other is configured to perform drive transmission using only an external gear. Configured to do. According to this, as described above, it is possible to make the rotation direction of the driven body the same regardless of the rotation direction of the drive source.
(Aspect H)
In (Aspect A) to (Aspect G), the reduction ratios of the drive transmission paths of the two systems are different. According to this, the speed can be increased as described in the above embodiment.
(Aspect I)
In (Aspect A) to (Aspect H), the rotation speed is the same at the time of normal rotation and the time of reverse rotation of the drive source. According to this, as described above, the rotation of the drive source can be controlled by a set of control constants.
(Aspect J)
In (Aspect A) to (Aspect I), of the two drive transmission paths, the drive transmission path located on the drive source side in the thrust direction is the drive located on the opposite side of the drive source in the thrust direction. Drive time is longer or is used more frequently than the transmission path. According to this, durability can be improved.
(Aspect K)
In (Aspect A) to (Aspect J), the drive transmission path of the two systems having a smaller number of drive transmission members has a longer drive time or is used more frequently than the other. According to this, it is possible to reduce noise.
(Aspect L)
In (Aspect A) to (Aspect K), a plurality of drive transmission paths of the two systems are provided corresponding to the plurality of driven bodies, and drive transmission of each of the two systems is performed by a rotational drive force from the drive source. Each driven body is driven via a path, and the deceleration ratio of at least two of the plurality of driven bodies is different between the normal rotation and the reverse rotation of the drive source. According to this, as described in the above-described embodiment, the rotation speeds of the two driven bodies can be finely adjusted by changing the rotation direction of the drive source.
(Aspect M)
In (Aspect L), the rotation speed is changed between the normal rotation and the reverse rotation of the drive source. According to this, it is possible to significantly change the rotation speeds of the two driven bodies without significantly increasing the rotation speeds of the drive source.
(Aspect N)
In (Aspect L) or (Aspect M), the difference in the reduction ratio is 3 [%] or less. According to this, the fine adjustment of the speed between the two driven bodies can be performed at 3 [%] or less.
(Aspect O)
In an image forming apparatus including an image forming means for forming an image and a driving means for transmitting and driving a driving force to a driven body, any one of (Aspect A) to (Aspect N) is used as the driving means. The drive device described was used. According to this, as described in the above-described embodiment, the rotation speed of the driven body can be changed without significantly increasing the rotation speed of the drive source.
(Aspect P)
In (Aspect O), as the driven body, a paper ejection roller such as a paper ejection roller 181a for ejecting a recording medium such as a recording paper P to a paper ejection portion such as a stack portion 150 can be used.
(Aspect Q)
In (Aspect O), as the driven body, a double-sided roller such as a double-sided roller 183 for inverting the front and back of the recording medium in order to form an image on both sides of the recording medium can be used.
(Aspect R)
In (Aspect O), a fixing roller such as a fixing roller 145 and a resist roller such as a resist roller 143a can be used as the plurality of driven bodies.
(Aspect S)
In (Aspect O), a fixing roller such as a fixing roller 145 and a paper ejection roller such as a paper ejection roller 181a can be used as the plurality of driven bodies.

1 Motor 1a Hasba gear 1b Worm gear 2 Idler gear 2a Drive connection claw 2b Drive connection claw 3 Pulley 3a Drive connection hole 4 Timing belt 5 Pulley 6 Drive gear 7 Rotating shaft 7a Fixed pin 8 External tooth gear 9 External tooth gear 9a Drive connection hole 10 External Tooth gear 11 Motor 11a Hasba gear 12 Idler gear 12a Drive connection claw 12b Drive connection claw 13 External tooth gear 13a Drive connection hole 14 External tooth gear 15 Drive gear 17 External tooth gear 18 External tooth gear 18a Drive connection hole 19 External tooth gear 20 External tooth Gear 21 Motor 21a Hasba gear 22 Idler gear 22a Drive connection claw 22b Drive connection claw 23 Internal tooth gear 23a Drive connection hole 24 External tooth gear 25 Drive gear 26 External tooth gear 27 External tooth gear 27a Drive connection hole 28 External tooth gear 30 Drive device 31 Motor 31a Hasuba gear 32 Idler gear 32a Internal tooth Hasuba gear part 32b External tooth Hasuba gear part 33 Idler gear 33a Drive connection claw 33b Drive connection claw 34 Pulley 34a Drive connection hole 35 Timing belt 36 Pulley 37 External tooth gear 37a External tooth gear 38 External tooth gear 39 Drive gear 40 External gear 41a Hasba gear 41 Motor 42 Idler gear 42a Drive connection claw 42b Drive connection claw 43 Pulley 43a Drive connection hole 44 Timing belt 45 Pulley 46 Drive gear 47 External tooth gear 48 External tooth gear 48a Drive connection hole 49 Rotating shaft 49a Fixed pin 52 Idler gear 52a Drive connecting claw 52b Drive connecting claw 53 Pulley 53a Drive connecting hole 54 Timing belt 55 Pulley 56 Drive gear 57 External tooth gear 58 External tooth gear 58a Drive connecting hole 59 Rotating shaft 59a Fixed pin 61 Motor 61a Hasba gear 62 Idler gear 62a Drive connection claw 62b Drive connection claw 63 External tooth gear 63a Drive connection hole 64 External tooth gear 65 External tooth gear 66 Drive gear 67 External tooth gear 68 Pulley 68a Drive connection hole 69 Timing belt 70 Pulley 72 Idler gear 72a Drive connection claw 72b Drive connection claw 73 External gear 73a Drive connection hole 74 External gear 75 External gear 76 Drive gear 77 External tooth gear 78 External tooth gear 78a Drive connection hole 81 Motor 81a Motor gear 82 Idler gear 82a Internal tooth hasba gear part 82b External tooth hasba gear part 83 Idler gear 83a Drive connection claw 83b Drive connection claw 84 External tooth gear 84a Drive connection hole 85 86 Pulley 86a Drive connection hole 87 Timing belt 88 Pulley 89 External tooth gear 93 Idler gear 93a Drive connection claw 93b Drive connection claw 94 External tooth gear 94a Drive connection hole 95 Drive gear 96 Pulley 96a Drive connection hole 97 Timing belt 98 Pulley 99 External tooth Gear 131 Side plate 132 Side plate 132a Bearing 132b Bearing 133 Side plate 140 Fixing device 141 Feeding cassette 142 Feeding roller 143 Resist roller vs. 143a Resist roller 143b Resist roller 145 Fixing roller 145a Heat generation source 147 Pressurized roller 150 Stack part 160 Process unit Body 162 Development device 162a Development roller 163 Charging device 164 Drum cleaning device 165 Optical writing unit 170 Refeeding path 171 Belt cleaning device 172 Cleaning backup roller 174 Primary transfer roller 175 Transfer unit 176 Drive roller 177 Tension roller 178 Secondary transfer roller 179 Intermediate transfer belt 181 Paper ejection roller vs. 181a Paper ejection roller 181b Paper ejection roller 182 Paper ejection sensor 183 Double-sided roller

Japanese Patent No. 5387704

Claims (7)

A drive source capable of forward and reverse rotation,
In an image forming apparatus that drives a fixing roller and a resist roller as driven bodies by the driving source.
A fixing roller drive transmitting means for transmitting the driving force of the driving source to the fixing roller,
A resist roller drive transmission means for transmitting the driving force of the drive source to the resist roller is provided.
The fixing roller drive transmission means and the resist roller drive transmission means each use two systems of drive transmission paths for transmitting the drive force and the drive force of the drive source among the two systems of drive transmission paths. It is equipped with a drive transmission path switching means for switching the drive transmission path to be transmitted to the driven body .
In the two drive transmission paths, one drive transmission path is composed of a plurality of pulleys and a belt member stretched on the pulleys, and the other drive transmission path is composed of a plurality of gear members.
The drive transmission path switching means moves in different directions in the thrust direction between the drive transmission paths of the two systems during normal rotation and reverse rotation of the drive source, and is among the drive transmission paths of the two systems. It has a rotatable moving rotating member that transmits the driving force from the driving source to one driving transmission path or the other driving transmission path.
The moving rotary member is a gear that directly meshes with the gear of the output shaft of the drive source.
An image forming apparatus characterized in that the deceleration ratios of the fixing roller and the resist roller are different between the normal rotation and the reverse rotation of the drive source. In the image forming apparatus according to claim 1,
The moving rotating member has a hasbar gear portion, and has a hasba gear portion.
By rotating the drive source in the normal direction, the moving rotating member moves toward one end side in the thrust direction and engages with the first drive transmitting member provided in the one driving transmission path from the moving rotating member. The drive is transmitted to the first drive transmission member, and the drive is transmitted to the first drive transmission member.
By reversing the drive source, the moving rotating member moves toward the other end in the thrust direction and engages with the second drive transmitting member provided in the other driving transmission path from the moving rotating member. An image forming apparatus characterized in that a drive is transmitted to the second drive transmission member . In the image forming apparatus according to claim 1 or 2 .
An image forming apparatus characterized in that the reduction ratios of the drive transmission paths of the two systems are different. The image forming apparatus according to any one of claims 1 to 3 .
An image forming apparatus characterized in that the rotation speed of the drive source is the same when the drive source is rotated forward and when the drive source is reversed. The image forming apparatus according to any one of claims 1 to 4 .
Of the two drive transmission paths, the drive transmission path located on the drive source side in the thrust direction has a longer drive time or is used than the drive transmission path located on the opposite side of the drive source in the thrust direction. An image forming apparatus characterized by high frequency. The image forming apparatus according to any one of claims 1 to 5 .
An image forming apparatus characterized in that the smaller number of drive transmission members among the two drive transmission paths has a longer drive time or a higher frequency of use than the other. In the image forming apparatus according to claim 1, 2, 3, 5 or 6 ,
An image forming apparatus characterized in that the rotation speed of the drive source is changed between forward rotation and reverse rotation of the drive source.

Images