JP6653083B2 - Image forming device - Google Patents

Description

  The present invention relates to an image forming apparatus.

  2. Description of the Related Art As an image forming apparatus such as a copying machine, a printer, a facsimile, or a multifunction peripheral thereof, there is known an image forming apparatus provided with a driving device for rotating a plurality of rotating bodies with one driving source.

  Patent Literature 1 discloses an image forming apparatus including a driving device that transmits a driving force of a driving motor that is a driving source to a registration roller and a fixing roller. In this drive device, a timing belt is stretched around a motor pulley of a drive motor, a first drive pulley, and a second drive pulley. The driving force transmitted to the first driving pulley via the timing belt is transmitted to the registration roller, and the driving force transmitted to the second driving pulley via the timing belt is transmitted to the fixing roller. The drive transmission path for transmitting the driving force to the registration roller has a clutch as a drive disconnecting means. The clutch is disengaged at a predetermined timing, and the drive transmission to the registration roller is interrupted. The rotation has stopped.

  In the driving device described in Patent Literature 1, when a drive transmission state to a registration roller is switched by a clutch, a sudden load change according to the torque of the registration roller occurs. The drive transmission member that transmits the drive force to the registration roller vibrates due to the sudden load change. The vibration propagates from the drive transmitting member that transmits the driving force to the registration roller to the second driving pulley via the timing belt, and the vibration is transmitted to the fixing roller via the driving transmission path that transmits the driving force to the fixing roller. Propagate. As a result, the fixing roller may vibrate, and an abnormal image such as uneven fixing may occur.

  In order to solve the above problems, the present invention provides a driving device having a plurality of rotating bodies, a driving source, and a plurality of driving transmission paths respectively transmitting the driving force of the driving source to the plurality of rotating bodies, At least one of the plurality of drive transmission paths is a disconnectable drive transmission path including drive disconnection means capable of switching between a state of transmitting the driving force of the driving source and a state of interrupting the transmission of the driving force. In one image forming apparatus, the disconnectable drive transmission path is configured to transmit the driving force of the drive source to the drive disconnection unit via a belt member, and the disconnectable drive transmission path is And an input drive transmission member to which a driving force is first input in at least one drive transmission path different from the connectable / disconnectable drive transmission path, wherein Source drive The at least one other drive transmission path, which is configured to mesh with the output member and transmits the torque of the rotating body to which the driving force is transmitted by the connectable / disconnectable drive transmission path, wherein the input drive transmission member meshes with the drive output member. The torque is smaller than the torque of the rotating body to which the driving force is transmitted.

  ADVANTAGE OF THE INVENTION According to this invention, the vibration of the rotating body to which a driving force is transmitted from a drive transmission path different from the disconnectable drive transmission path can be suppressed.

FIG. 1 is a schematic configuration diagram illustrating a printer according to an embodiment. FIG. 2 is a perspective view illustrating a driving device included in the printer and members that are rotationally driven by the driving device. (A) is a front view of a drive device, (b) is the rear view. (A) is a front view which shows only the drive transmission member of a drive device, (b) is the rear view. 9 is a graph showing torque between a fixing roller and a rotating body that is driven and transmitted via an electromagnetic clutch held by a paper supply side bracket.

Hereinafter, an electrophotographic printer (hereinafter, simply referred to as a printer) that forms an image by an electrophotographic method will be described as an image forming apparatus to which the present invention is applied.
First, a basic configuration of the printer according to the embodiment will be described. FIG. 1 is a schematic configuration diagram illustrating a printer according to the embodiment. Referring to FIG. 1, the printer includes a photosensitive member 1 as a latent image carrier, a sheet feeding cassette 20 as a sheet storage unit configured to be detachable from a main body housing 50, and the like. A plurality of recording sheets are stored in the sheet cassette 20 in a sheet bundle.

  The recording sheet in the paper feed cassette 20 is sent out of the cassette by the rotation of the paper feed roller 35 and reaches the inside of the paper feed path 42. Thereafter, the sheet is nipped by the transport nip of the first transport roller pair 41 and transported in the paper feed path 42 from the upstream side to the downstream side in the transport direction. A pair of registration rollers 49 is provided near the end of the paper feed path 42. The conveyance of the recording sheet is temporarily stopped in a state where the leading end of the recording sheet abuts the registration nip of the registration roller pair 49. At that time, the skew of the recording sheet is corrected.

  The registration roller pair 49 starts rotating at a timing at which the recording sheet can be superimposed on the toner image on the surface of the photoconductor 1 at a transfer nip described later, and sends the recording sheet toward the transfer nip. At this time, the first conveying roller pair 41 starts rotating at the same time, and restarts the temporarily stopped conveyance of the recording sheet S.

  The main body housing 50 of the printer holds a manual paper feed unit including a manual paper feed tray 43, a manual paper feed roller 43c, and the like. The recording sheet manually fed to the manual feed tray 43 of the manual feed unit is sent out from the inside of the manual feed tray 43 by the rotation of the manual feed roller 43c. Then, after passing through a separation nip due to the contact between the manual feed roller 43 c and the separation pad, the sheet P enters a region of the paper feed path 42 upstream of the registration roller pair 49. Thereafter, in the same manner as the recording sheet sent out from the sheet feeding cassette 20, after passing through the registration roller pair 49, it is sent to a transfer nip described later.

  A charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, a cleaning blade 2, and the like are provided around a drum-shaped photosensitive member 1 which is driven to rotate counterclockwise in FIG. I have. The charging roller 4 including the conductive rubber roller rotates while forming contact with the photosensitive member 1 to form a charging nip. A charging bias output from a power supply is applied to the charging roller 4. As a result, a discharge is generated between the surface of the photoconductor 1 and the surface of the charging roller 4 in the charging nip, so that the surface of the photoconductor 1 is uniformly charged.

  The latent image writing device 7 includes an LED array, and performs exposure of the uniformly charged surface of the photoconductor 1 with LED light. In the uniformly charged background portion of the photoconductor 1, the region irradiated with light attenuates the potential. As a result, an electrostatic latent image is formed on the surface of the photoconductor 1.

  The electrostatic latent image passes through a developing area facing the developing device 8 with the rotation of the photoconductor 1. The developing device 8 has a developer accommodating section and a developing section. The developer accommodating section accommodates a developer containing a non-magnetic toner and a magnetic carrier. The developer accommodating section has a screw 8b for transporting the developer to be supplied to the developing roller 8a.

  The developing roller 8a includes a rotatable developing sleeve made of a cylindrical non-magnetic member, and a magnet roller fixed in the sleeve so as not to rotate along with the developing sleeve. Then, a part of the developer conveyed by the screw 8b is pumped up on the surface of the developing sleeve by the magnetic force generated by the magnet roller. The layer thickness of the developer carried on the surface of the developing sleeve is regulated when passing through the facing position between the sleeve and the doctor grade while rotating along the surface of the developing sleeve. Thereafter, the photosensitive member 1 moves while rubbing on the surface of the photosensitive member 1 in a development region facing the photosensitive member 1.

  To the developing sleeve, a developing bias having the same polarity as the toner or the background potential of the photoconductor 1 is applied. The absolute value of the developing bias is larger than the absolute value of the latent image potential and smaller than the absolute value of the background portion potential. For this reason, in the developing area, a developing potential for electrostatically moving toner from the sleeve side to the latent image side acts between the electrostatic latent image on the photoconductor 1 and the developing sleeve. On the other hand, between the background portion of the photoreceptor 1 and the developing sleeve, a background potential acts to electrostatically move the toner from the background portion side to the sleeve side. As a result, in the developing area, the toner selectively adheres to the electrostatic latent image on the photoconductor 1, and the electrostatic latent image is developed.

  Above the developing device 8, a toner cartridge 9 is provided. The toner cartridge 9 has a toner storage section 19a for storing toner and a waste toner recovery section 19b for recovering waste toner. The toner accommodating portion 19a has agitators 9a and 9b for agitating the toner contained therein and a toner replenishing member 9c for replenishing the developing device 8 with the internal toner. The toner replenishing member 9c is rotated in response to a replenishment operation signal output from the control unit, thereby replenishing the developing device 8 with toner in an amount corresponding to the rotational drive amount.

  The toner image formed on the photoreceptor 1 by the development enters a transfer nip where the photoreceptor 1 and a transfer roller 10 serving as a transfer unit are in contact with the rotation of the photoreceptor 1. A charging bias having a polarity opposite to the potential of the latent image on the photoconductor 1 is applied to the transfer roller 10, thereby forming a transfer electric field in the transfer nip.

  As described above, the registration roller pair 49 sends the recording sheet toward the transfer nip at a timing at which the recording sheet can be superimposed on the toner image on the photoconductor 1 in the transfer nip. The toner image on the photoconductor 1 is transferred to the recording sheet brought into close contact with the toner image by the transfer nip by the action of the transfer electric field and the nip pressure.

The transfer residual toner that has not been transferred to the recording sheet adheres to the surface of the photoconductor 1 after passing through the transfer process in the transfer nip. The transfer residual toner is scraped off from the surface of the photoreceptor 1 by the cleaning blade 2 in contact with the photoreceptor 1, and then sent out of the unit casing by the recovery screw 3. The transfer residual toner discharged from the unit casing is sent to the waste toner collecting section 19b of the toner cartridge 9 by the transport device. The waste toner collecting unit 19b is provided with a waste toner collecting and stirring screw 11 for evenly equalizing the waste toner collected by the waste toner collecting unit 19b.
The surface of the photoconductor 1 that has been cleaned by the cleaning blade 2 as a cleaning member is neutralized by the neutralization unit, and then uniformly charged again by the charging roller 4.

  The recording sheet that has passed through the transfer nip where the photoconductor 1 and the transfer roller 10 contact each other is sent to the fixing device 44. The fixing device 44 forms a fixing nip by abutting a fixing roller 44a including a heat source such as a halogen lamp and a pressing roller 44b pressed toward the fixing roller 44a. A toner image is fixed on the surface of the recording sheet sandwiched between the fixing nips by the action of heat or pressure.

  The printer can be switched between a single-sided mode in which an image is formed on only one side of a recording sheet and a double-sided mode in which an image is formed on both sides of a recording sheet. In the case of the single-sided mode or in the case of the double-sided mode and images have already been formed on both sides of the recording sheet S, the switching claw 47 is positioned at the position indicated by the solid line in the figure. After passing through the fixing device 44, the recording sheet passes through a paper discharge path 45, is sandwiched between a reverse discharge roller 46 a and a paper discharge roller 46 b, and is stacked on a stack portion 50 a provided on the upper surface of the main body housing 50.

  On the other hand, if the mode is the double-sided mode and an image is formed only on one side of the recording sheet, the switching claw 47 is swung to the position indicated by the dotted line in the figure. After passing through the fixing device 44, the recording sheet passes through the paper discharge path 45, is guided to the reverse conveyance path 48 by the switching claw 47, and is sandwiched between the reverse discharge roller 46a and the reverse roller 46c. Then, at the timing when the end of the recording sheet enters the reversing nip formed by the reversing discharge roller 46a and the reversing roller 46c, the reversing discharge roller 46a is driven to rotate in the reverse direction. At this time, the switching claw 47 is operated to swing from the position indicated by the dotted line in the drawing to the position indicated by the solid line in the drawing. The recording sheet, which has started to return by the reverse rotation of the reverse discharge roller 46a, is conveyed by the first re-supply roller 48a, the second re-supply roller 48b, and the third re-supply roller 48c provided in the reversal conveyance path 48, and then is subjected to registration. The sheet is re-sent to the registration nip of the roller pair 49. Then, after the toner image is transferred to the other surface by the transfer nip, the toner image is discharged to the outside of the apparatus by the reverse discharge roller 46a and the discharge roller 46b via the fixing device 44 and the discharge path 45.

  FIG. 2 is a perspective view illustrating a driving device 100 provided in the printer and members that are driven to rotate by the driving device 100. 3A is a front view of the driving device 100, and FIG. 3B is a rear view. FIG. 4A is a front view showing only a drive transmission member of the drive device 100, and FIG. 4B is a rear view.

  The driving device 100 rotationally drives the fixing roller 44a, the second re-feed roller 48b, the third re-feed roller 48c, the registration roller 49, the first transport roller 41, the paper feed roller 35, and the manual paper feed roller 43c. Further, the agitators 9a and 9b of the toner cartridge 9, the toner replenishing member 9c, and the waste toner collecting and stirring screw 11 are also rotationally driven. In addition, the lifting member 43b that moves the bottom plate 43a of the manual feed tray 43 up and down is also driven.

  The drive device 100 includes a paper discharge side bracket 100a that holds a drive transmission member disposed on the paper discharge side starting from the photoconductor 1, and a paper supply side that holds a drive transmission member disposed on the paper supply side. And a bracket 100b. The paper discharge side bracket 100a includes a drive motor 101, a drive transmission member for transmitting a drive force to the fixing roller 44a, and a drive transmission for transmitting a drive force to the second re-feed roller 48b and the third re-feed roller 48c. Holding the member.

  The paper feed side bracket 100b holds a drive transmission member that transmits a driving force to the registration roller 49, the first transport roller 41, the paper feed roller 35, and the manual paper feed roller 43c. Further, it holds a drive transmitting member for transmitting a driving force to the agitators 9a and 9b of the toner cartridge 9, the toner replenishing member 9c, the waste toner collecting and stirring screw 11 and the elevating member 43b. The drive transmission from the drive transmission member held by the paper discharge side bracket 100a to the drive transmission member held by the paper supply side bracket 100b is performed via the connection timing belt 113.

  The motor gear 101a of the drive motor 101 has a first branch gear 102 for transmitting a driving force to the fixing roller 44a, the second re-feed roller 48b, and the third re-feed roller 48c, and a drive transmission member for the feed side bracket 100b. The second branch gear 109 for transmitting the force meshes with the second branch gear 109.

  The first branch gear 102 meshes with the retransmission input gear 103a of the fixing retransmission branch gear 103. The retransmission input gear 103a is engaged with the gear of the retransmission electromagnetic clutch 108. The retransmission electromagnetic clutch 108 is attached to one end of the shaft of the second retransmission roller 48b. At the other end of the shaft of the second re-sending roller 48b, a gear constituting a re-sending drive transmission path 140 for transmitting the driving to the third re-sending roller 48c is attached. When the retransmission electromagnetic clutch 108 is OFF, the gear of the retransmission electromagnetic clutch 108 idles with respect to the axis of the second retransmission roller 48b, and the drive transmission to the axis of the second retransmission roller 48b is interrupted. At the start of the reverse rotation of the reversing discharge roller 46a, the resending electromagnetic clutch 108 is switched from OFF to ON. Then, the driving force is transmitted to the second re-sending roller 48b via the re-sending electromagnetic clutch 108, and the second re-sending roller 48b is rotationally driven. Further, the driving force is transmitted to the third re-sending roller 48c via the second re-sending roller 48b and the re-sending drive transmission path 140, and the third re-sending roller 48c is rotationally driven. When the leading end of the recording sheet conveyed in the reverse conveyance path 48 comes into contact with the registration roller 49, the resending electromagnetic clutch 108 is switched from ON to OFF, and the driving of the second resending roller 48b and the third resending roller 48c is primarily performed. Stop. Then, at the timing when the registration roller 49 is driven to convey the recording sheet to the transfer nip, the retransmission electromagnetic clutch 108 is turned on, and the driving of the second retransmission roller 48b and the third retransmission roller 48c is restarted. When the recording sheet is discharged out of the apparatus, the resending electromagnetic clutch 108 is turned off, and the driving of the second resending roller 48b and the third resending roller 48c is stopped.

  Further, the first fixing gear 104a of the first fixing drive transmission member 104 is meshed with the fixing input gear 103b of the fixing re-transmission branch gear 103. The first fixing drive transmitting member 104 has a first fixing pulley 104b. A fixing timing belt 105 is stretched around the first fixing pulley 104b and the second fixing pulley 106a of the second fixing drive transmitting member. The second fixing drive transmitting member has a second fixing gear 106b, and the input gear portion 107a of the third fixing drive transmitting member 107 meshes with the second fixing gear 106b. Further, the third fixing drive transmitting member 107 has an output gear portion 107b, and the final fixing gear 144 provided on the fixing roller 44a meshes with the output gear portion 107b.

  The driving force of the drive motor 101 is transmitted to the first fixing drive transmitting member 104 via the first branch gear 102 and the fixing re-sending branch gear 103. Then, the light is transmitted from the first fixing drive transmitting member 104 to the second fixing drive transmitting member 106 via the fixing timing belt 105, and then to the fixing roller 44 a via the third fixing drive transmitting member 107 and the final fixing gear 144. The driving force is transmitted, and the fixing roller 44a is driven to rotate.

  The paper discharge side output gear 110a of the paper discharge side drive output member 110 meshes with the second branch gear 109. The paper discharge side drive output member 110 has a paper discharge side output pulley 110b, and a paper discharge side timing belt 111 is stretched between the paper discharge side output pulley 110b and the relay pulley 112. The connection timing belt 113 described above is also wound around the relay pulley 112. The connection timing belt 113 is stretched around the relay pulley 112 and the feed-side input pulley 114a of the feed-side drive input member 114 held by the feed-side bracket 100b.

  The driving force of the drive motor 101 is transmitted to the relay pulley 112 via the second branch gear 109, the paper output drive output member 110, and the paper output timing belt 111. Then, the driving force is transmitted to the paper feeding side drive input member 114 via the relay pulley 112 and the connection timing belt 113, and the driving force of the driving motor 101 is transmitted to the paper feeding side bracket 100b.

  The paper feed side drive input member 114 is provided with a paper feed side input gear 114b, and the first idler gear portion 115a of the paper feed branch drive member 115 meshes with the paper feed side input gear 114b. The paper feed branch driving member 115 has a paper feed branch gear 115b that meshes with a gear of a paper feed electromagnetic clutch 116 attached to the shaft of the paper feed roller 35. The gear of the registration electromagnetic clutch 124 and the second idler gear 117 are engaged with the first idler gear portion 115a of the paper feed branch drive member 115.

  The driving force of the drive motor 101 transmitted to the paper feed side drive input member 114 is transmitted to the paper feed electromagnetic clutch 116 and the registration electromagnetic clutch 124 via the paper feed branch drive member 115. When the recording sheets set in the paper feed cassette 20 are fed, by turning on the paper feed electromagnetic clutch 116, the driving force is transmitted to the paper feed roller 35 via the paper feed electromagnetic clutch 116, The roller 35 is driven to rotate. As a result, the recording sheet in the paper feed cassette 20 is fed out by the paper feed roller 35 and fed to the paper feed path 42. At the timing when the leading edge of the recording sheet fed by the feed roller 35 hits the registration roller 49, the feed electromagnetic clutch 116 is turned off, and the rotation of the feed roller 35 is stopped.

  The registration electromagnetic clutch 124 is turned on at a timing when the recording sheet can be superimposed on the toner image on the photoconductor 1 in the transfer nip, and drives the registration roller 49 to rotate. When the trailing edge of the recording sheet passes through the registration roller 49, the recording sheet is turned off and the driving of the registration roller 49 is stopped.

  The second idler gear 117 meshing with the first idler gear portion 115a of the paper feed branch drive member 115 has a transport branch gear of a transport elevation drive transmission member 118 for transmitting a driving force to the first transport roller 41 and the elevation member 43b. The part 118a is engaged. The gear of the transfer electromagnetic clutch 119 attached to the shaft of the first transfer roller 41 meshes with the transfer branch gear portion 118a.

  The driving force of the drive motor 101 transmitted to the paper feed side drive input member 114 is input to the transport electromagnetic clutch 119 via the paper feed branch drive member 115, the second idler gear 117, and the transport elevation drive transmission member 118. When the recording sheet set in the paper feed cassette 20 is fed, the conveying electromagnetic clutch 119 is turned ON, and the driving force is transmitted to the first conveying roller 41 via the conveying electromagnetic clutch 119, so that the first conveying roller 41 Drive rotationally. As a result, the recording sheet fed from the sheet feed cassette 20 is transported by the first transport roller 41 toward the registration roller 49.

  At the timing when the leading edge of the recording sheet abuts on the registration roller 49, the conveyance electromagnetic clutch 119 is turned off, and the rotation of the first conveyance roller 41 is stopped. Then, at the timing when the registration roller 49 is driven to convey the recording sheet to the transfer nip, the conveyance electromagnetic clutch 119 is turned ON, and the driving of the first conveyance roller 41 is restarted. Then, when the recording sheet is discharged out of the apparatus, the conveyance electromagnetic clutch 119 is turned off, and the driving of the first conveyance roller 41 is stopped.

  The first lifting relay gear 136a of the lifting relay drive transmission member 136 meshes with a gear provided coaxially with the transport branch gear portion 118a of the transport lifting drive transmission member 118. The gear of the lifting electromagnetic clutch 126 attached to the shaft of the lifting member 43b meshes with the second lifting relay gear 136b of the lifting relay drive transmission member 136.

  The driving force of the drive motor 101 transmitted to the paper feed side drive input member 114 is transmitted to the lifting relay drive transmission member 136 via the paper feed branch drive member 115, the second idler gear 117, and the transport lifting drive transmission member 118. You. Then, the driving force is transmitted from the lifting / lowering relay drive transmission member 136 to the lifting / lowering member 43b via the lifting / lowering electromagnetic clutch 126, and the bottom plate 43a of the manual feed tray is raised and lowered.

  The second idler gear 117 is meshed with the recovery / supply branch gear 120a of the branch drive transmission member 120. The collection relay gear 121 and the supply input gear 127 of the supply drive transmission path 128 mesh with the recovery supply branch gear 120a. The collection relay gear 121 meshes with a collection output gear 122 that rotates integrally with a collection joint 123 that is drivingly connected to the waste toner collection and stirring screw 11.

  The driving force of the drive motor 101 transmitted to the paper feed side drive input member 114 is transmitted to the paper feed branch drive member 115, the second idler gear 117, and the branch drive transmission member 120. Then, a driving force is transmitted to the waste toner collecting and stirring screw 11 via the collecting relay gear 121, the collecting output gear 122, and the collecting joint 123, and the waste toner collecting and stirring screw 11 is rotationally driven.

  The supply drive transmission path 128 includes a supply electromagnetic clutch 128a and a plurality of gears. The driving force of the drive motor 101 transmitted from the branch drive transmission member 120 to the supply input gear 127 is transmitted to the supply joint 132 that is drivingly connected to the toner supply member 9c via the supply drive transmission path 128. Then, a driving force is transmitted to the toner supply member 9c via the supply joint 132, and the toner supply member 9c is rotationally driven. The toner replenishing member 9c is provided with a stirring gear 133 for transmitting a driving force to the agitators 9a and 9b (see FIG. 2). Then, a driving force is transmitted to the agitators 9a and 9b via the stirring gear 133, and the agitators 9a and 9b are driven to rotate together with the toner replenishing member 9c.

  The supply electromagnetic clutch 128a is turned on in response to the supply operation signal output from the control unit, the driving force of the drive motor is transmitted to the toner supply member 9c, and the agitators 9a and 9b and the toner supply member 9c rotate. Then, the toner is supplied to the developing device 8. When an amount of toner corresponding to the amount of rotation is supplied to the developing device 8, the supply electromagnetic clutch 128a is turned off.

  The gear of a manual electromagnetic clutch 134 attached to the shaft of the manual paper feed roller 43c meshes with the manual branch gear 120b of the branch drive transmission member 120.

  When feeding the recording sheet set in the manual feed tray 43, the above-mentioned lifting electromagnetic clutch 126 is turned on, the lifting member 43b is driven, and the bottom plate 43a of the manual tray is raised. Then, when the recording sheet placed on the bottom plate 43a comes into contact with the manual feed roller 43c, the lifting / lowering electromagnetic clutch 126 is turned off, and the driving of the lifting / lowering member 43b is stopped. Next, the manual feed electromagnetic clutch 134 is turned on, the driving force of the drive motor 101 is transmitted to the manual feed roller 43c, and the manual feed roller 43c is rotated to register the recording sheet set in the manual tray 43. Paper is fed toward the roller 49. When the leading end of the recording sheet fed from the manual feed tray 43 contacts the registration roller 49, the manual feed electromagnetic clutch 134 is turned off, and the rotation of the manual feed roller 43c is temporarily stopped. At the timing when the registration electromagnetic clutch 124 switches from OFF to ON, the manual electromagnetic clutch 134 is turned ON, and the rotational drive of the manual paper feed roller 43c is resumed. As a result, the recording sheet is conveyed toward the transfer nip by the registration roller 49 and the manual feed roller 43c. When the trailing end of the recording sheet passes through the manual feed roller 43c, the manual electromagnetic clutch 134 is turned off to stop the rotation of the manual feed roller 43c. When the feeding of the recording sheets from the manual feed tray is completed, the elevating electromagnetic clutch 126 is turned on, the bottom plate 43a of the manual feed tray is lowered, and when the bottom plate 43a is lowered to a specified position, the elevating electromagnetic clutch 126 is turned off. To

  In the driving device 100 of the present embodiment, the second and third re-feed rollers 48b and 48c, the registration roller 49, the first transport roller 41, the paper feed roller 35, the manual paper feed roller 43c, the toner replenishing member 9c, and the elevating member 43b An electromagnetic clutch is provided in each of the drive transmission paths. Thus, without stopping the driving of the driving device 100, the second and third re-feed rollers 48b and 48c, the registration roller 49, the first transport roller 41, the paper feed roller 35, the manual paper feed roller 43c, and the toner supply member 9c are provided. The rotation of the lifting member 43b can be stopped or started at a predetermined timing. Accordingly, the fixing roller 44a which is always driven to rotate, and the rotating members (the second and third re-feed rollers 48b and 48c, the registration roller 49, and the first transport roller) which stop driving or start driving at a predetermined timing. 41, the paper feed roller 35, the manual feed roller 43c, the toner supply member 9c, and the elevating member 43b) can be driven by one drive motor 101. As a result, the number of motors can be reduced, and the device can be made inexpensive. Also, by reducing the number of motors, noise of the motors can be suppressed, and the device can be made quieter.

  However, when the electromagnetic clutch is turned off and the drive is turned off, or when the drive is turned on and the drive is connected, a sudden load change occurs, and the sudden load change causes an impact, and the drive transmission for transmitting the driving force to the electromagnetic clutch. Vibrating the member. When this vibration propagates to the fixing roller, unevenness in rotation occurs in the fixing roller 44a, which may cause uneven fixing.

  For this reason, in the present embodiment, in order to suppress the load fluctuation at the time of switching ON / OFF of the electromagnetic clutch, the rotating members (the second and third re-feed rollers 48b and 48c, the registration rollers 49, the first transport roller 41, the paper feed roller 35, the manual paper feed roller 43c, the toner supply member 9c, and the elevating member 43b) have lower torque than the torque of the fixing roller 44a.

  FIG. 5 is a graph showing the torque of the fixing roller and the torque of the rotating body whose drive is transmitted via the electromagnetic clutch. The feed roller 35, the first transport roller 41, the registration roller 49, the toner replenishing member 9c, the manual feed roller 43c, and the elevating member, which are rotary members that are driven and transmitted via an electromagnetic clutch held by the feed side bracket 100b. The torque of the fixing roller 44b is 0.4 N · m or less, and is (（) or less of the torque of the fixing roller 44a. Further, the torque of the second re-feed roller 48b and the third re-feed roller 48c is about 0.05 N · m, which is (1/20) or less of the torque of the fixing roller 41. As described above, since the torque of the rotating member having the electromagnetic clutch in the drive transmission path is reduced, it is possible to suppress a load variation when the electromagnetic clutch is turned off to cut off the drive or when the electromagnetic clutch is turned on to connect the drive. This can reduce the shock when the electromagnetic clutch is turned off and the drive is turned off, or when the electromagnetic clutch is turned on and the drive is connected, and the vibration generated by the shock can be reduced.

  The paper supply side bracket 100b has a total of six electromagnetic clutches including a paper supply electromagnetic clutch 116, a conveyance electromagnetic clutch 119, a registration electromagnetic clutch 124, a lifting electromagnetic clutch 126, a supply electromagnetic clutch 128a, and a manual electromagnetic clutch 134. . These generate an impact when switching the drive transmission state, resulting in vibration. However, in the present embodiment, the drive transmission of the paper feed side bracket 100b to the drive transmission member is transmitted by the belt member using the paper discharge side timing belt 111 and the connection timing belt 113. As a result, the vibration generated by switching the drive transmission state of the electromagnetic clutch held by the paper feed side bracket 100b is transmitted to the paper feed side bracket 100b through the connection timing belt 113 and the paper discharge side timing belt 111. It will be transmitted to the member. Since the connection timing belt 113 and the discharge timing belt 111 are formed of an elastic member such as rubber, when vibration is transmitted to the connection timing belt 113 and the discharge timing belt 111, the connection timing belt 113 and the discharge timing belt 111 are elastically deformed. Attenuate the vibration component. As a result, it is possible to suppress the vibration generated by the bracket on the paper feed side from propagating to the drive transmission member on the paper discharge side, and to suppress the rotation unevenness of the fixing roller 44a.

  Further, in the present embodiment, the vibration on the paper feed side can be attenuated in two stages, the connection timing belt 113 and the paper discharge side timing belt 111.

  Further, in the present embodiment, the motor gear 101a of the drive motor 101 applies the first branch gear 102 for transmitting the driving force to the fixing roller 44a, and the driving force to the drive transmission member held by the sheet feeding side bracket 100b. The second branch gear 109 for transmission meshes with the drive motor, and the drive transmission path to the fixing roller 44a and the drive transmission path to the drive transmission member held by the paper feed side bracket 100b are branched at the drive motor. ing.

  As the drive motor 101, a drive motor having a rated torque equal to or higher than a torque determined based on a torque of a rotating body driven by the drive motor 101 and a predetermined safety factor is used. In the present embodiment, the fixing roller 44a, the second re-feed roller 48b, the third re-feed roller 48c, the registration roller 49, the first transport roller 41, the elevating member 43b, the paper feed roller 35, the manual paper feed roller 43c, the waste toner collecting and stirring A drive motor having a rated torque equal to or higher than the torque determined by the sum of the torque of the screw 11 and the toner supply member 9c and a predetermined safety factor is used. In the present embodiment, as described above, the rotator (the paper feed roller 35, the first transport roller 41, the registration roller 49, and the toner replenishing member 9c) to which the driving force is transmitted from the drive transmission member held by the paper supply side bracket. The torque of the manual feed roller 43c and the elevating member 43b) is equal to or less than (１ ／) of the torque of the fixing roller 44a, and the load fluctuation when the drive transmission state of the electromagnetic clutch is switched is the rated torque of the drive motor. Significantly lower. In addition, as described above, the signal is attenuated by the connection timing belt 113 and the discharge-side timing belt 111 before the power is transmitted to the motor gear. Therefore, the influence of vibration when switching the drive transmission state of the electromagnetic clutch to the output torque of the drive motor can be sufficiently reduced. As a result, the vibration component generated by switching the drive transmission state of the electromagnetic clutch held by the paper feed side bracket 100b that propagates to the motor gear 101a is smaller than the driving force of the drive motor.

  Unlike the gear, the motor gear 101a is driven to rotate by a driving force generated by the motor gear 101a. Therefore, the vibration generated by switching the drive transmission state by the electromagnetic clutch held on the paper feed side bracket 100b causes its own drive. Take it by force. In addition, since the vibration component transmitted to the motor gear is small with respect to the driving force, the motor gear 101a can continue to rotate at a constant speed without vibrating due to the vibration component transmitted to the motor gear. Thus, it is possible to prevent the vibration from being propagated to the first branch gear 102 via the motor gear 101a. Therefore, it is possible to prevent the fixing roller 44a from vibrating due to the vibration generated by switching the drive transmission state while being held by the paper supply side bracket 100b, and to suppress the rotation unevenness of the fixing roller 44a. . As a result, it is possible to suppress the occurrence of fixing unevenness and the like.

  In the present embodiment, a fixing timing belt 105 is provided in a drive transmission path to the fixing roller 44a, and the driving force is transmitted to the fixing roller 44a via a belt member. Accordingly, the fixing timing belt 105 elastically deforms and attenuates the vibration generated at the time of switching the drive transmission state of the retransmission electromagnetic clutch 108 held by the paper discharge side bracket 100a. Thereby, the vibration propagating to the fixing roller 44a can be reduced, and the rotation unevenness of the fixing roller 44a can be suppressed.

  Further, as shown in FIG. 5, the torque of the second re-feed roller 48b and the third re-feed roller 48c is about 0.05 Nm, which is (1/20) of the torque of the fixing roller 44a. . As a result, it is possible to suppress a load fluctuation occurring when the drive transmission state of the retransmission electromagnetic clutch 108 is switched. Therefore, the vibration generated when the drive transmission state of the retransmission electromagnetic clutch 108 is switched can be suppressed, and the rotation unevenness of the fixing roller 44a can be suppressed.

  In addition, a rotating body having an electromagnetic clutch in the drive transmission path (the second re-feed roller 48b, the third re-feed roller 48c, the registration roller 49, the first transport roller 41, the elevating member 43b, the paper feed roller 35, the manual feed roller 43c, By reducing the torque of the toner supply member 9c), the drive connection can be performed even if the electromagnetic force is weak. Thus, an inexpensive and small electromagnetic clutch can be used.

What has been described above is merely an example, and each embodiment has a specific effect.
(Aspect 1)
A driving device 100 having a plurality of rotating bodies, a driving source such as a drive motor 101, and a plurality of driving transmission paths for transmitting the driving force of the driving source to the plurality of rotating bodies, At least one of the images is a disconnectable drive transmission path including a drive disconnection unit such as an electromagnetic clutch capable of switching between a state of transmitting the driving force of the driving source and a state of interrupting the transmission of the driving force. In the forming apparatus, the disconnectable drive transmission path is configured to transmit the driving force of the drive source to the drive disconnection unit via a belt member such as a connection timing belt 113; An input drive transmission member such as the second branch gear 109 to which a driving force is first input in the possible drive transmission path, and at least one drive transmission path different from the disconnectable drive transmission path. An input drive transmitting member such as a first branch gear 102 to which a driving force is first input is meshed with a drive output member such as the motor gear 101a of the drive source, and is driven by the disconnectable drive transmission path. The torque of the rotating body (in this embodiment, the registration roller 49, the first transport roller 41, the elevating member 43b, the paper feed roller 35, the manual paper feed roller 43c, and the toner replenishing member 9c) to which the force is transmitted is determined by the drive output. The torque is smaller than the torque of a rotating body such as the fixing roller 44a to which the driving force is transmitted by the at least one other drive transmission path in which the input drive transmission member meshes with the member.
In the first aspect, by having the following three points, the vibration generated when the drive transmission state is switched by the drive disconnecting means such as the electromagnetic clutch is transmitted to the drive output member such as the motor gear 101a by the first branch gear 102. The transmission of the input drive transmission member to the at least one other drive transmission path meshing with the input drive transmission member is satisfactorily suppressed.
1. The disconnectable drive transmission path is configured to transmit the driving force of the drive source to a drive disconnection unit via a belt member.
2. An input drive transmission member, such as a second branch gear 109, to which a driving force is first input in the disconnectable drive transmission path, and a first drive drive in at least one drive transmission path different from the disconnectable drive transmission path A point that an input drive transmission member such as the first branch gear 102 to which a force is input is meshed with a drive output member such as the motor gear 101a of the drive source.
3. The torque of the rotating body to which the driving force is transmitted by the disconnectable drive transmission path is smaller than the torque of the rotating body to which the driving force is transmitted by the at least one other driving transmission path.
First, by having the above point 3, the torque of the rotating body, to which the driving force is transmitted by the disconnectable drive transmission path, is changed to the fixing roller 44a, to which the driving force is transmitted from the at least one other drive transmission path. As compared with the case where the torque is larger than the torque of the rotating body, the load fluctuation when the drive transmission state is switched by the drive connection / disconnection means can be reduced. Thus, vibration generated when the drive transmission state is switched by the drive connection / disconnection unit can be reduced. Next, by having the above point 1, the vibration generated by the drive connection / disconnection means propagates to the belt member such as the connection timing belt 113. The vibration transmitted to the belt member is attenuated by the elastic deformation of the belt member. By virtue of the above point 2, the vibration attenuated by the belt member is propagated to the at least one other drive transmission path via the drive output member of the drive source such as the motor gear 101a. . A drive transmission member such as a gear has play such as backlash between the drive transmission member on the upstream side in the drive transmission direction that transmits the driving force to the drive transmission member. Therefore, when the vibration is propagated, the vibration itself also occurs. On the other hand, the drive output member of the drive source, unlike the drive transmission member such as a gear, rotates at a constant speed by the drive force generated by itself, receives vibration by the drive force generated by itself, and attenuates the vibration. Let it. Thus, it is possible to sufficiently suppress the vibration that propagates to another drive transmission path via the drive output member of the drive source. As a result, vibration of the rotating body to which the driving force is transmitted via another drive transmission path can be favorably suppressed.

(Aspect 2)
In the first aspect, it is rotatable with an image forming means (formed of a photoreceptor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10 and the like) for forming an image on a recording medium such as a recording sheet. A fixing device for fixing an image on the recording medium by bringing the recording medium into contact with the fixing roller; and one of a plurality of drive transmission paths is provided by the fixing roller. A fixing drive transmission path for transmitting a force (in this embodiment, the first branch gear 102, the fixing retransmission branch gear 103, the first fixing drive transmitting member 104, the fixing timing belt 105, the second fixing drive transmitting member 106, the third A fixing drive transmission member 107 and a final fixing gear 144), wherein the fixing drive transmission path includes a drive output member such as a motor gear 101a and a first branch gear 102 or the like. Is the other at least one drive transmission path meshed with the input drive transmission member.
According to this, as described in the embodiment, rotation unevenness of the fixing roller 44a can be suppressed, and occurrence of fixing unevenness can be suppressed.

(Aspect 3)
In the aspect 1 or 2, the drive disconnection means is an electromagnetic clutch.
According to this, the rotational drive of the rotating body can be controlled by ON / OFF control of the electromagnetic clutch. Further, in the present embodiment, the torque of the rotating body to which the driving force is transmitted by the disconnectable drive transmission path is changed to the torque of the rotating body by which the driving force is transmitted from the driving transmission path not having the driving disconnection means. Smaller than. Thus, even if an inexpensive and small electromagnetic clutch having a weak electromagnetic force is used as the electromagnetic clutch, it is possible to satisfactorily connect the drive. As a result, the size of the device can be reduced, and the cost of the device can be prevented from increasing.

(Aspect 4)
In any one of the first to third aspects, an image forming means for forming an image on a recording medium such as a recording sheet (consisting of a photosensitive member 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like); A rotatable paper feed roller 35, and a paper feed device for feeding a recording medium to the image forming unit by the paper feed roller 35. One of a plurality of drive transmission paths is provided to the paper feed roller. A paper feed drive transmission path for transmitting the driving force (in this embodiment, the second branch gear 109, the paper output drive output member 110, the paper output timing belt 111, the relay pulley 112, the connection timing belt 113, the paper feed side Drive input member 114, a paper feed branch drive member, and a paper feed electromagnetic clutch 116), wherein the paper feed drive transmission path is a disconnectable drive transmission path.
According to this, the feed roller 35 can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the paper feed roller 35 has a small torque and can suppress a load change when the drive transmission state of the drive connection / disconnection means such as the paper supply electromagnetic clutch 116 is switched. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 5)
In any one of the first to fourth aspects, an image forming means for forming an image on a recording medium such as a recording sheet (including a photoreceptor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like); A registration roller 49 that conveys the recording medium to the image forming unit at a predetermined timing, and one of the plurality of drive transmission paths includes a registration drive transmission path ( In the present embodiment, the second branch gear 109, the discharge side drive output member 110, the discharge side timing belt 111, the relay pulley 112, the connection timing belt 113, the feed side drive input member 114, the feed branch drive member 115, And the registration drive transmission path is a disconnectable drive transmission path.
According to this, the registration roller 49 can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the registration roller 49 has a small torque with respect to the fixing roller 44 a and suppresses a load variation when the drive transmission state of the drive connection / disconnection unit such as the registration electromagnetic clutch 124 is switched. Can be. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 6)
In any one of the first to fifth aspects, an image forming unit (consisting of a photoconductor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like) for forming an image on a recording medium such as a recording sheet is provided. And a transport roller such as a first transport roller 41 that transports the recording medium, and one of the plurality of drive transmission paths is a transport drive transmission path that transmits the driving force to the transport roller (in the present embodiment, , Second branch gear 109, paper output drive output member 110, paper output timing belt 111, relay pulley 112, connection timing belt 113, paper feed drive input member 114, paper feed branch drive member 115, second idler gear 117. , The transport drive transmission path is a disconnectable drive transmission path.
According to this, the transport rollers such as the first transport roller 41 can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the transport roller has a small torque with respect to the fixing roller 44a, and can suppress a load fluctuation when the drive transmission state of the drive disconnecting means such as the transport electromagnetic clutch 119 is switched. it can. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 7)
The image forming apparatus according to any one of aspects 1 to 6, wherein the latent image carrier such as the photoreceptor 1, a developing device 8 that develops a latent image on the latent image carrier using a developer, A developer accommodating portion such as a toner cartridge 9 to be accommodated; and a rotatable replenishing member such as a toner replenishing member 9 c for replenishing the developer in the developer accommodating portion to the developing device 8. One of the drive transmission paths is a supply drive transmission path for transmitting the driving force to the supply member (in the present embodiment, the second branch gear 109, the paper output drive output member 110, the paper output timing belt 111). , The relay pulley 112, the connection timing belt 113, the paper feed side drive input member 114, the paper feed branch drive member 115, the second idler gear 117, the branch drive transmission member 120, and the supply drive transmission path 128. A formation), dispense driving pathway is disconnection drivable transmission path.
According to this, a replenishing member such as the knurling member 9c can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the replenishing member has a small torque with respect to the fixing roller 44a, and can suppress a load fluctuation when the drive transmission state of the drive disconnecting means such as the replenishing electromagnetic clutch 128a is switched. it can. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 8)
In any one of the first to seventh aspects, a latent image carrier such as the photoconductor 1, a developing device 8 for developing a latent image on the latent image carrier using a developer, and a developing device on the latent image carrier Transfer means such as a transfer roller 10 for transferring the transferred image to a recording medium, and cleaning means such as a cleaning blade 2 for removing toner remaining on the surface of the latent image carrier after being transferred by the transfer means. A waste toner conveying member such as a waste toner collecting and stirring screw 11 for conveying the waste toner removed by the cleaning device, and one of a plurality of drive transmission paths is provided for transmitting the driving force to the waste toner conveying member. Toner conveyance drive transmission path (in the present embodiment, the second branch gear 109, the paper discharge side drive output member 110, the paper discharge side timing belt 111, the relay pulley 112, the connection timing Guberuto 113, the paper feed side drive input member 114, the sheet feeding branch drive member 115, a second idler gear 117, the branch drive transmission member 120, the recovery relay gear 121, recovered output gear 122, a configuration) with recovery joint 123.
According to this, the waste toner conveying member such as the waste toner collecting and stirring screw 11 can be rotationally driven by the drive motor.

(Aspect 9)
In any one of the first to eighth aspects, an image forming means for forming an image on a recording medium such as a recording sheet (including a photoreceptor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like) A manual feed tray 43 on which the recording medium is manually set; and a manual feed roller 43c for feeding the recording medium set on the manual feed tray 43 to the image forming means. One of them is a manual paper feed drive transmission path for transmitting the driving force to the manual paper feed roller 43c (in this embodiment, the second branch gear 109, the paper output side drive output member 110, the paper output side timing belt). 111, a relay pulley 112, a connection timing belt 113, a paper feed side drive input member 114, a paper feed branch drive member 115, a second idler gear 117, a branch drive transmission member 120, and the like. A configuration) in the fine manual feed electromagnetic clutch 134, the manual sheet feeding drive transmission path is disconnection drivable transmission path.
According to this, the manual feed roller 43c can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the manual feed roller 43c has a small torque with respect to the fixing roller 44a and suppresses a load fluctuation when the drive transmission state of the drive connection / disconnection unit such as the manual electromagnetic clutch 134 is switched. Can be suppressed. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 10)
In any one of the first to ninth aspects, an image forming means (consisting of a photoconductor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like) for forming an image on a recording medium such as a recording sheet. And a manual feed tray 43 on which the recording medium is manually set. One of the plurality of drive transmission paths is a manual drive for transmitting the driving force to an elevating member 43b for raising and lowering a bottom plate 43a of the manual feed tray 43. Transmission path (in this embodiment, the second branch gear 109, the discharge side drive output member 110, the discharge side timing belt 111, the relay pulley 112, the connection timing belt 113, the paper feed side drive input member 114, the paper feed branch drive (Consisting of a member 115, a second idler gear 117, a transport elevating drive transmitting member 118, an elevating relay drive transmitting member 136, and an elevating electromagnetic clutch 126). I, the manual feed drive transmission path is disconnection drivable transmission path.
According to this, the lifting member 43b can be rotationally driven by the drive motor. Further, as shown in FIG. 5, the elevating member has a small torque with respect to the fixing roller 44a and can suppress a load fluctuation when the drive transmission state of the drive connection / disconnection means such as the elevating electromagnetic clutch 126 is switched. it can. Further, a small and inexpensive electromagnetic clutch can be used as the drive disconnecting means.

(Aspect 11)
In any one of the first to tenth aspects, an image forming unit (including a photoreceptor 1, a charging roller 4, a latent image writing device 7, a developing device 8, a transfer roller 10, and the like) for forming an image on a recording medium such as a recording sheet is provided. A reversing conveyance path 48 for reversing the recording medium having an image formed on one side thereof by the image forming means and conveying the recording medium to the image forming means again, and one of a plurality of drive transmission paths includes the reversing conveyance path A reverse conveyance drive transmission path for transmitting the driving force to conveyance rollers such as a second retransmission roller 48b and a third retransmission roller 48c provided in the path (in this embodiment, the first branch gear 102 includes a fixing retransmission branch gear 103, a gear of the retransmission electromagnetic clutch 108. The retransmission electromagnetic clutch 108, a retransmission drive transmission path 140, and the like). A drive disconnection means such as a latch 108.
According to this, the transport rollers such as the second re-feed roller 48b and the third re-feed roller 48c can be driven to rotate by the drive motor.

Reference Signs List 1 photosensitive member 2 cleaning blade 4 charging roller 7 latent image writing device 8 developing device 9 toner cartridge 9a, 9b agitator 9c toner replenishing member 10 transfer roller 11 waste toner collecting and stirring screw 19a toner storage portion 19b waste toner collecting portion 20 Cassette 35 Paper feed roller 41 First transport roller 43 Manual feed tray 43a Bottom plate 43b Elevating member 43c Roller 44 Fixing device 44a Fixing roller 44b Pressure roller 48 Reverse transport path 48a First resend roller 48b Second resend roller 48c Third resend roller 49 Registration roller 100 Drive unit 100a Paper discharge side bracket 100b Paper supply side bracket 101 Drive motor 101a Motor gear 102 First branch gear 103 Fixing retransmission branch gear 103a Retransmission input gear 103b Fixing input gear 104 First fixing drive transmission member 104a first fixing gear 104b first fixing pulley 105 fixing timing belt 106 second fixing drive transmitting member 106a second fixing pulley 106b second fixing gear 107 third fixing drive transmitting member 107a input gear 107b output gear 108 resending Electromagnetic clutch 109 Second branch gear 110 Paper discharge side drive output member 110a Paper discharge side output gear 110b Paper discharge side output pulley 111 Paper discharge side timing belt 112 Relay pulley 113 Connection timing belt 114 Paper supply side drive input member 114a Paper supply side Input pulley 114b Feed side input gear 115 Feed branch drive member 115a First idler gear 115b Feed branch gear 116 Feed electromagnetic clutch 117 Second idler gear 118 Transport elevating drive transmission member 118a Transport branch gear 119 Transport electromagnetic clutch 120 Branch Drive train Member 120a Recovery supply branch gear 120b Manual feed branch gear 121 Recovery relay gear 122 Recovery output gear 123 Recovery joint 124 Registration electromagnetic clutch 126 Elevating electromagnetic clutch 127 Supply input gear 128 Supply drive transmission path 128a Supply electromagnetic clutch 132 Supply joint 133 Stirring gear 134 Manual feed Electromagnetic clutch 136 Lifting / lowering relay drive transmission member 136a First lifting / lowering relay gear 136b Second lifting / lowering relay gear 140 Retransmission drive transmission path 144 Final fixing gear

JP-A-10-129880

Claims (11)

A plurality of rotating bodies,
A drive source, and a drive device having a plurality of drive transmission paths that respectively transmit the driving force of the drive source to the plurality of rotating bodies,
At least one of the plurality of drive transmission paths is a disconnectable drive transmission path including drive disconnection means capable of switching between a state of transmitting the driving force of the driving source and a state of interrupting the transmission of the driving force. In an image forming apparatus,
The disconnectable drive transmission path is configured to transmit the driving force of the drive source to the drive disconnection unit via a belt member, and the driving force is first transmitted in the disconnectable drive transmission path. An input drive transmission member to be input, and an input drive transmission member to which a driving force is first input in at least one drive transmission path different from the disconnectable drive transmission path, include a drive output member of the drive source. It is configured to mesh,
A rotating body to which the driving force is transmitted by the at least one other drive transmission path in which the input drive transmission member meshes with the drive output member, the torque of the rotating body to which the driving force is transmitted by the disconnectable drive transmission path. An image forming apparatus characterized in that the torque is smaller than the torque of the image forming apparatus. The image forming apparatus according to claim 1,
Image forming means for forming an image on a recording medium;
A fixing device that has a rotatable fixing roller, and that contacts a recording medium with the fixing roller to fix an image on the recording medium;
One of the plurality of drive transmission paths is a fixing drive transmission path that transmits the driving force to the fixing roller,
The image forming apparatus according to claim 1, wherein the fixing drive transmission path is the at least one other drive transmission path in which the input output transmission member meshes with the drive output member. The image forming apparatus according to claim 1, wherein
An image forming apparatus according to claim 1, wherein said drive disconnecting means is an electromagnetic clutch. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
A sheet feeding device that includes a rotatable sheet feeding roller and feeds a recording medium to the image forming unit by the sheet feeding roller;
One of the plurality of drive transmission paths is a paper feed drive transmission path that transmits the driving force to the paper feed rollers,
The image forming apparatus according to claim 1, wherein the paper feed drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
A registration roller that conveys the recording medium at a predetermined timing to the image forming unit,
One of the plurality of drive transmission paths is a registration drive transmission path that transmits the driving force to the registration roller,
The image forming apparatus according to claim 1, wherein the registration drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
And a transport roller for transporting the recording medium,
One of the plurality of drive transmission paths is a transport drive transmission path that transmits the driving force to the transport roller,
The image forming apparatus according to claim 1, wherein the transport drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
A latent image carrier,
A developing device that develops the latent image on the latent image carrier using a developer,
A developer accommodating section for accommodating the developer;
A replenishing member that is rotatably provided and replenishes the developer in the developer accommodating portion to the developing device;
One of the plurality of drive transmission paths is a supply drive transmission path that transmits the driving force to the supply member,
The image forming apparatus according to claim 1, wherein the supply drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
A latent image carrier,
A developing device that develops the latent image on the latent image carrier using a developer,
Transfer means for transferring the developed image on the latent image carrier to a recording medium,
A cleaning device that removes residual toner adhered to the surface of the latent image carrier after being transferred by the transfer unit;
A waste toner transport member that transports waste toner removed by the cleaning device,
An image forming apparatus, wherein one of the plurality of drive transmission paths is a waste toner conveyance drive transmission path for transmitting the driving force to the waste toner conveyance member. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
A manual feed tray on which the recording medium is manually set,
And a manual sheet feeding roller for feeding the recording medium set in the manual feed tray to the image forming means,
One of the plurality of drive transmission paths is a manual paper feed drive transmission path that transmits the driving force to the manual paper feed roller,
The image forming apparatus according to claim 1, wherein the manual paper feed drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
A manual feed tray on which the recording medium is manually set,
One of the plurality of drive transmission paths is a manual drive transmission path that transmits the driving force to a lifting member that raises and lowers the bottom plate of the manual tray,
The image forming apparatus, wherein the manual drive transmission path is the disconnectable drive transmission path. The image forming apparatus according to claim 1, wherein
Image forming means for forming an image on a recording medium;
A recording medium having an image formed on one side thereof by the image forming unit is reversed, and a reversal conveyance path for conveying the recording medium to the image forming unit is provided.
One of the plurality of drive transmission paths is a reverse transport drive transmission path that transmits the driving force to a transport roller provided in the reverse transport path,
The image forming apparatus according to claim 1, wherein the reverse conveyance drive transmission path includes the drive disconnection unit.

Images