JP7456227B2 - Conveyance direction switching device and image forming device - Google Patents

Description

The present invention relates to a conveying direction switching device and an image forming device.

Patent Document 1 discloses a device including a document reading section that reads image information of a document, an image forming section that forms an image on a sheet based on the image information of the document read by the document reading section, and the image forming section. A paper post-processing section is attached to the main body and performs post-processing of the paper on which an image has been formed, and a paper post-processing section is provided below the document reading section as an ejection section for discharging the paper on which the image has been formed by the image forming section. In an image forming apparatus in which a space is formed, an upper discharge port and a lower discharge port for discharging the paper are disposed in the space, and the paper is connected to the upper discharge port to eject the paper into the image. An image forming apparatus is disclosed, characterized in that a relay conveyance path is formed for conveying paper from a forming section to the sheet post-processing section.

Japanese Patent Application Publication No. 2004-70374

When conveying a recording medium, there are cases where switching is made to a plurality of conveyance paths. In this case, a switching member is required to switch the conveyance path.

The present invention aims to provide a transport direction switching device and an image forming device that can reduce power consumption compared to devices that use electrical drive means such as electromagnets to switch transport paths.

The present invention of claim 1 is a transport direction switching device comprising a first transport path and a second transport path along which a recording medium is transported, a switching member that switches the transport direction of the recording medium between the first transport path and the second transport path, a transport member provided on at least one of the first transport path and the second transport path and transporting the recording medium, a drive force transmission member that transmits a driving force to the transport member, and a connecting mechanism that connects the drive force transmission member and the switching member, wherein the drive force transmission member is a drive gear, the connecting mechanism has a movable gear that meshes with the drive gear and is connected to the switching member via the movable gear, the movable gear has a movable shaft and rotates around the movable shaft, and the movable shaft is connected to the switching member.

In the present invention according to claim 2, the conveyance direction of the recording medium is switched between a first conveyance path and a second conveyance path in which the recording medium is conveyed, and the first conveyance path and the second conveyance path. a switching member, a conveyance member provided on at least one of the first conveyance path and the second conveyance path and conveys a recording medium, and a driving force transmission member that transmits a driving force to the conveyance member; a coupling mechanism for moving the switching member by the drive force transmission member , the drive force transmission member being a drive gear, and the coupling mechanism having a movable gear that meshes with the drive gear; The movable gear has a movable shaft, rotates around the movable shaft, and is a conveyance direction switching device in which the movable gear is coupled to the switching member.

The present invention according to claim 3 is the conveyance direction switching device according to claim 1 or 2, which includes a movement restriction section that restricts a movement range of the movable shaft.

In the present invention according to claim 4 , the switching member rotates around a rotating shaft, and the movement regulating portion is an arc-shaped regulating groove centered on the rotating shaft, and the movable shaft is inserted into the regulating groove. 4. The conveyance direction switching device according to claim 3 , wherein

The present invention according to claim 5 includes: a first conveyance path for conveying a recording medium printed on one side so as to be ejected; and a second conveyance path for pulling back a recording medium printed on one side for double-sided printing. , a switching member for switching the conveyance direction of the recording medium between the first conveyance path and the second conveyance path; and a switching member provided in each of the first conveyance path and the second conveyance path to convey the recording medium. a driving force transmitting member that transmits a driving force to the conveying member, and a connecting mechanism that connects the driving force transmitting member and the switching member , the driving force transmitting member being a driving gear. The coupling mechanism has a movable gear that meshes with the drive gear, and is coupled to the switching member via the movable gear, and the movable gear has a movable shaft, and the movable gear has a movable shaft that is centered on the movable shaft. The image forming apparatus rotates, and the movable shaft is connected to the switching member .

The present invention according to claim 6 includes: a first conveyance path for conveying a recording medium printed on one side so as to be ejected; and a second conveyance path for pulling back a recording medium printed on one side for double-sided printing. , a switching member for switching the conveyance direction of the recording medium between the first conveyance path and the second conveyance path; and a switching member provided in each of the first conveyance path and the second conveyance path to convey the recording medium. a conveying member that transmits a driving force to the conveying member, a driving force transmitting member that transmits a driving force to the conveying member, and a coupling mechanism that moves the switching member by the driving force transmitting member , the driving force transmitting member being a driving gear, The coupling mechanism has a movable gear that meshes with the drive gear, and is coupled to the switching member via the movable gear, and the movable gear has a movable shaft and rotates about the movable shaft. , an image forming apparatus in which the movable shaft is connected to the switching member .

According to the present invention according to Claims 1, 2 , 5, or 6, power consumption can be suppressed compared to the case where an electric drive means such as an electromagnet is used for switching the conveyance path. Further, the switching member can be moved using the rotation of the drive gear. Further, the switching member can be moved via the movable shaft.

According to the present invention according to claim 3 , in addition to the effects of the present invention according to claim 1 or 2 , it is possible to restrict the movement range of the movable shaft.

According to the present invention according to claim 4, in addition to the effects of the present invention according to claim 3 , it is possible to restrict the movement range of the movable shaft in the radial direction and the circumferential direction.

1 is a side sectional view showing an image forming apparatus according to an embodiment of the present invention. 1 is a side cross-sectional view showing a conveyance direction switching device and its surroundings according to an embodiment of the present invention. FIG. 2 is a side view showing a conveyance direction switching device according to an embodiment of the present invention. It is a side view showing a drive gear and a connection mechanism in a conveyance direction switching device concerning an embodiment of the present invention. It is a front view showing a movable gear and a frame in a conveyance direction switching device concerning an embodiment of the present invention. 1A and 1B are diagrams illustrating a state before paper transport in a single-sided printing mode of a transport direction switching device according to an embodiment of the present invention, in which FIG. 1A is a side view showing a drive gear and a connecting mechanism, and FIG. The conveying direction switching device according to the embodiment of the present invention is shown in a state immediately after being driven in the single-sided printing mode, in which (a) is a side view showing the drive gear and the coupling mechanism, and (b) is a side view showing the switching member and its surroundings. It is. The conveyance direction switching device according to the embodiment of the present invention shows the state before paper conveyance in the single-sided printing mode, (a) is a side view showing the drive gear and the coupling mechanism, (b) is a side view showing the switching member and its surroundings. It is a diagram. A state in which the conveying direction switching device according to an embodiment of the present invention is conveying paper in single-sided printing mode, (a) is a side view showing the drive gear and the coupling mechanism, (b) is a side view showing the switching member and its surroundings. It is a diagram. The conveying direction switching device according to the embodiment of the present invention is shown in a state before driving in double-sided printing mode, in which (a) is a side view showing the drive gear and the coupling mechanism, and (b) is a side view showing the switching member and its surroundings. It is. The state of paper transport during one-sided printing in the double-sided printing mode of the transport direction switching device according to the embodiment of the present invention is shown, (a) is a side view showing the drive gear and the coupling mechanism, and (b) is the switching member and its surroundings. FIG. The paper conveyance stop state during one-sided printing in the double-sided printing mode of the conveyance direction switching device according to the embodiment of the present invention is shown, (a) is a side view showing the drive gear and the coupling mechanism, (b) is the switching member and its FIG. 3 is a side view showing the surrounding area. 1A and 1B show a state of a transport direction switching device according to an embodiment of the present invention immediately after paper transport during other side printing in double-sided printing mode, where FIG. 1A is a side view showing a drive gear and a connecting mechanism, and FIG. The paper conveyance direction switching device according to the embodiment of the present invention is shown in a state in which paper conveyance is started during one-sided printing in the double-sided printing mode, (a) is a side view showing the drive gear and the coupling mechanism, (b) is a side view showing the switching member and It is a side view showing the surroundings. The paper conveyance state during one-sided printing in the double-sided printing mode of the conveyance direction switching device according to the embodiment of the present invention is shown, (a) is a side view showing the drive gear and the coupling mechanism, and (b) is a side view showing the switching member and its FIG. 3 is a side view showing the surrounding area.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an image forming apparatus 10 according to an embodiment of the present invention. The image forming apparatus 10 has an image forming apparatus main body 12, and the image forming apparatus main body 12 is formed with ejection ports 14a and 14b for ejecting paper used as a recording medium. Further, the upper surface of the image forming apparatus main body 12 is used as a discharge section 16 from which a sheet of paper having a developer image fixed thereon is discharged.

Further, within the image forming apparatus main body 12, an image forming section 18 that forms a developer image on paper is arranged. The image forming unit 18 includes a photosensitive drum 20 used as an image holder that holds an image, a charging device 22 that uniformly charges the surface of the photosensitive drum 20, and a photosensitive drum 20 that is uniformly charged by the charging device 22. A latent image forming device 24 that forms an electrostatic latent image on the surface of the body, a developing device 26 that uses a developer to develop the latent image formed by the latent image forming device 24, and a developing device 26 that develops the latent image. A transfer device 28 transfers the developer image formed on the surface of the photoreceptor drum 20 by development onto paper, and after the developer image is transferred to the paper by the transfer device 28, it is transferred to the surface of the photoreceptor drum 20. It has a cleaning device 30 that cleans residual developer and the like.

Further, a fixing device 32 is disposed within the image forming apparatus main body 12 to fix the developer image formed on the paper by the image forming section 18 to the paper.

In addition, within the image forming device main body 12, recording medium supplying devices 34, 36 that supply recording media to the image forming unit 18 are arranged. The recording medium supplying devices 34, 36 have recording medium storage units 38, 40 that store recording media in a stacked state, and delivery rolls 44, 46 that send the recording media stored in the recording medium storage units 38, 40 to the main transport path 42 described below.

The main transport path 42 is a transport path that extends from the recording medium storage units 38 and 40 to the discharge port 14a. This main conveyance path 42 includes, in order from the upstream side in the recording medium conveyance direction, recording medium storage sections 38 and 40, a registration roll 48, a space between the photoreceptor drum 20 and the transfer device 28, a fixing device 32, and a conveyance device described later. A direction switching device 50 is arranged.

The registration roll 48 temporarily stops the movement of the leading end of the recording medium supplied from either of the recording medium supply devices 34 and 36 to match the timing at which a toner image is formed on the surface of the photoreceptor drum 20. Then, the movement of the leading edge of the paper to the transfer section formed by the photosensitive drum 20 and the transfer device 28 is restarted.

The transfer device 28 electrostatically transfers the toner image formed on the surface of the photoreceptor drum 20 onto a sheet of paper using the applied transfer bias.

Further, the reversing conveyance path 52 is a conveyance path from the discharge port 14b to the registration roll 48, and for example, two conveyance rolls 54 and 56 are arranged in order from the upstream side in the paper conveyance direction. The transport rolls 54 and 56 transport the recording medium toward the registration roll 48 while reversing the paper on which the toner image is formed on one side.

FIG. 2 shows the fixing device 32, the conveyance direction switching device 50, and their peripheral configurations.
The fixing device 32 has a fixing device main body 60, and a heating roll 62 and a pressure section 64 are arranged within the fixing device main body 60. The heating roll 62 includes a cylindrical roll portion 66 and a heater 68 disposed within the roll portion 66, and the roll portion 66 is heated by energizing the heater 68.

The pressure unit 64 is disposed inside the endless belt 70, including an endless belt 70 as an endless belt, a belt guide member 72 that rotatably guides the endless belt 70, and moves toward the heating roll 62 side together with the endless belt 70. It is composed of a pressing part 74 that is pressed.

The endless belt 70 is provided between the heating roll 62 and the pressing part 74, and the heating roll 62 and the endless belt 70 are brought into pressure contact with each other by the pressing part 74, thereby causing a gap between the heating roll 62 and the endless belt 70. The toner image is fixed on the recording medium passing through it.

An entrance side guide member 76 fixed to the fixing device main body 60 is provided on the entrance side of the fixing device 32 . Further, on the exit side of the fixing device 32, an exit side guide member 78 fixed to the fixing device main body 60 is provided.

The conveyance direction switching device 50 discharges the sheet of paper, on which the toner image has been fixed on one side by the fixing device 32, toward the discharge section 16 from the discharge port 14a. In addition, when forming a developer image on the other side of a sheet of paper with a developer image formed on one side, the sheet is conveyed toward the discharge port 14b, and when the vicinity of the trailing edge of the sheet reaches By starting driving in the opposite direction at the right timing, and driving in the opposite direction, the recording medium on which the developer image is formed on one surface is sent to the reversing conveyance path 52 from the rear end side.

The conveyance direction switching device 50 has three rolls. That is, the first conveying member 80 is a drive roll, the second conveying member 82 is a pinch roll that presses into contact with the first conveying member 80 from below, and the first conveying member 80 is applied from above. It has a third conveying member 84 that is a pinch roll that makes pressure contact.

The conveyance direction switching device 50 also includes a switching member 86 . This switching member 86 is provided on the front side of the first conveying member 82 and has a rotating shaft 88 on the first conveying member 82 side, and the fixing device 32 side rotates around this rotating shaft 82. ing. In this embodiment, when the switching member 86 is in the position shown by the dotted line in FIG. The leading end is guided and the paper is ejected from the ejection port 14a. When the switching member 86 is in the position shown by the solid line in FIG. When a portion of the paper is ejected from the reversing path 52 and the first conveyance member 80 is reversed to reverse the paper, the paper is guided to the reversal path 52 .

As shown in FIG. 3, a drive gear 90 constituting a driving force transmission member is provided at one end in the axial direction of the first conveyance member 82, and the first conveyance member 82 is rotated in forward and reverse directions via this drive gear 90. rotationally driven in the direction. Further, this drive gear 90 is connected to the switching member 86 via an idle gear 94 and a movable gear 96 that constitute a connection mechanism 92.

That is, the movable gear 96 is provided at the center of the movable gear 96 so that a movable shaft 98 can rotate freely. As shown in FIG. 4, this movable shaft 98 is connected to the switching member 86. Further, as shown in FIGS. 5 and 6, the movable gear 96 is housed within a frame 100. The frame 100 is fixed to the image forming apparatus main body 12. Further, a movement regulating portion 102 is provided on a side surface of the frame 100. The movement restriction portion 102 is formed as a restriction groove formed in an arc shape centered on the rotation shaft 82 of the switching member 86. A movable shaft 98 fits into this regulation groove. Therefore, the movement range of the movable shaft 98 is restricted in the radial direction and the circumferential direction by the restriction groove, and movement is permitted only in the portion where the restriction groove is formed.

Next, the operation of the transport direction switching device 50 will be explained.

6 to 9 show examples of operation in the single-sided printing mode.
First, before single-sided printing, as shown in FIGS. 6(a) and 6(b), the drive gear 90 stops driving, and a clockwise moment acts on the switching member 86 due to its own weight. The movable shaft 98 hits the lower end of the movement restriction part 102, and the switching member 86 is stopped in a downwardly downward state.

Next, as shown in FIGS. 7A and 7B, the drive gear 90 begins to rotate in the direction in which the paper is ejected (clockwise in FIG. 7A). When the drive gear 90 rotates in the direction to eject the paper, the movable gear 96 rotates clockwise via the idle gear 94. When the movable gear 96 rotates clockwise, a counterclockwise moment about the rotating shaft 88 of the switching member 86 acts on the movable shaft 98 due to the engagement between the idle gear 94 and the movable gear 96, and the movable shaft 98 starts moving in the direction of the arrow while being guided by the movement regulating section 102. The switching member 86 follows along with the movable shaft 98 and begins to move upward.

When the drive gear 90 further rotates clockwise, the switching member 86 moves up together with the movable shaft 98 via the idle gear 94 and the movable gear 96, as shown in FIGS. 8(a) and 8(b). When the drive gear 90 further rotates clockwise, the movable shaft 98 moves to the upper end of the movement regulating section 102 and stops at this upper end position while continuing to rotate, as shown in FIGS. 9(a) and 9(b). do. When the movable shaft 98 moves to the upper end of the movement regulating section 102, the switching member 86 moves to open the lower side, and the paper is guided to pass under the switching member 86, as shown in FIG. 9(b). Then, the paper is ejected from the ejection port 14a while being sandwiched between the first transport member 80 and the second transport member 82.

FIGS. 10 to 15 show operational examples of the double-sided printing mode.

Even in the double-sided printing mode, after printing on one side and before printing on the other side, as shown in FIGS. A clockwise moment acts on the member 86, the movable shaft 98 hits the lower end of the movement regulating portion 102, and the switching member 86 is stopped in a downwardly downward state.

Next, as shown in FIGS. 11(a) and 11(b), the drive gear 90 is turned counterclockwise. When the drive gear 90 rotates counterclockwise, the movable gear 96 rotates counterclockwise via the idle gear 94. When the movable gear 96 rotates counterclockwise, a clockwise moment about the rotating shaft 88 of the switching member 86 acts on the movable shaft 98 due to the engagement between the idle gear 94 and the movable gear 96, and the movable shaft 98 starts moving in the direction of the arrow while being guided by the movement regulating section 102. The switching member 86 follows along with the movable shaft 98 and begins to move upward.

When the paper is transported in this state, as shown in FIG. 11(b), the paper is guided to pass above the switching member 86, and the leading edge of the paper is sandwiched between the first transport member 80 and the third transport member 84 and transported.

Next, as shown in FIGS. 12(a) and 12(b), before the trailing edge of the sheet passes between the first conveying member 80 and the third conveying member 84, the first conveying member 80 rotates. The sheet stops, and the paper stops in a state where it is sandwiched between the first conveying member 80 and the third conveying member 84.

Next, as shown in FIGS. 13(a) and 13(b), the drive gear 90 is reversed and starts rotating clockwise. When the drive gear 90 starts rotating clockwise, the movable gear 96 rotates clockwise via the idle gear 94. When the movable gear 96 rotates clockwise, a counterclockwise moment about the rotating shaft 88 of the switching member 86 acts on the movable shaft 98 due to the engagement between the idle gear 94 and the movable gear 96, and the movable shaft 98 starts moving from the lower end of the movement regulating section 102 toward the upper end.

The paper sandwiched between the first conveying member 80 and the third conveying member 84 starts being conveyed toward the reversing path 52 by the rotation of the first conveying member 80 and the third conveying member 84. .

When the drive gear 90 further rotates clockwise, the switching member 86 follows the movable shaft 98 and moves upward, as shown in FIGS. 14(a) and 14(b).

Next, as shown in FIGS. 15A and 15B, when the movable shaft 98 moves to the upper end of the movement regulating section 102, the switching member 86 guides the paper toward the reversing conveyance path 52.

In the above embodiment, the movable shaft 98 and the switching member 86 are directly connected, but the movable shaft 98 and the switching member 86 may be connected via a link or a cam.

10 Image forming device 12 Image forming device main body 14a, 14b Discharge port 16 Discharge section 18 Image forming section 20 Photosensitive drum 22 Charging device 24 Latent image forming device 26 Developing device 28 Transfer device 30 Cleaning device 32 Fixing device 34, 36 Recording medium Supply device 38, 40 Recording medium storage section 42 Main conveyance path 44, 46 Delivery roll 48 Registration roll 50 Conveyance direction switching device 52 Reversing conveyance path 54, 56 Conveyance roll 60 Fixing device main body 62 Heating roll 64 Pressure section 66 Roll section 68 Heater 70 Endless belt 72 Belt guide member 74 Pressing part 76 Entrance side guide member 78 Outlet side guide member 80 First conveying member 82 Second conveying member 84 Third conveying member 86 Switching member 88 Rotating shaft 90 Drive gear 92 Connection Mechanism 94 Idle gear 96 Movable gear 98 Movable shaft 100 Frame 102 Movement restriction section

Claims (6)

a first conveyance path and a second conveyance path through which the recording medium is conveyed;
a switching member that switches the conveyance direction of the recording medium between the first conveyance path and the second conveyance path;
a conveyance member that is provided on at least one of the first conveyance path and the second conveyance path and conveys the recording medium;
a driving force transmission member that transmits driving force to the conveying member;
a connection mechanism that connects the driving force transmission member and the switching member;
has
The driving force transmission member is a driving gear, the coupling mechanism has a movable gear that meshes with the driving gear, and is connected to the switching member via the movable gear,
The movable gear has a movable shaft, rotates around the movable shaft, and the movable shaft is connected to the switching member.
Conveyance direction switching device. a first conveyance path and a second conveyance path through which the recording medium is conveyed;
a switching member that switches the conveyance direction of the recording medium between the first conveyance path and the second conveyance path;
a conveyance member that is provided on at least one of the first conveyance path and the second conveyance path and conveys the recording medium;
a driving force transmission member that transmits driving force to the conveying member;
a connection mechanism that moves the switching member by the driving force transmission member;
has
The driving force transmission member is a driving gear, and the coupling mechanism has a movable gear that meshes with the driving gear, and is connected to the switching member via the movable gear,
The movable gear has a movable shaft, rotates around the movable shaft, and the movable shaft is connected to the switching member.
Conveyance direction switching device. The conveyance direction switching device according to claim 1 or 2, further comprising a movement restriction section that restricts a movement range of the movable shaft. 4. The movable shaft according to claim 3 , wherein the switching member rotates about a rotating shaft, and the movement regulating portion is an arcuate regulating groove centered about the rotating shaft, and the movable shaft fits into the regulating groove. Conveyance direction switching device. a first conveyance path that conveys a recording medium printed on one side so as to discharge it;
a second transport path for pulling back a recording medium printed on one side for double-sided printing;
a switching member that switches the conveyance direction of the recording medium between the first conveyance path and the second conveyance path;
a conveyance member that is provided in each of the first conveyance path and the second conveyance path and conveys the recording medium;
a driving force transmission member that transmits driving force to the conveying member;
a connection mechanism that connects the driving force transmission member and the switching member;
has
The driving force transmission member is a driving gear, the coupling mechanism has a movable gear that meshes with the driving gear, and is connected to the switching member via the movable gear,
The movable gear has a movable shaft, rotates around the movable shaft, and the movable shaft is connected to the switching member.
Image forming device. a first conveying path for conveying the recording medium printed on one side so as to be discharged;
a second conveying path for pulling back the recording medium printed on one side for double-sided printing;
a switching member that switches a conveying direction of the recording medium between the first conveying path and the second conveying path;
a conveying member provided on each of the first conveying path and the second conveying path, the conveying member conveying a recording medium;
a driving force transmission member that transmits a driving force to the conveying member;
a coupling mechanism for moving the switching member by the driving force transmission member;
having
the driving force transmission member is a driving gear, the connecting mechanism has a movable gear that meshes with the driving gear and is connected to the switching member via the movable gear,
The movable gear has a movable shaft, rotates around the movable shaft, and the movable shaft is connected to the switching member.
Image forming device.

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