Patent Grant
9535388
This application is based on and claims priority under 35 USC 119 from Japanese Patent Application No. 2014-064741 filed Mar. 26, 2014.
The present invention relates to a recording material transporting apparatus, and an Image forming apparatus.
According to an aspect of the invention, there is provided a recording material transporting apparatus including:
a transport member that transports a recording material in a transport direction;
a linkage portion that moves in an intersection direction in connection with movement of the transport member in the direction intersecting the transport direction; and
a rotating member that rotates about a rotating shaft disposed along the intersection direction, that includes a helical cam on a circumference of the rotating shaft, and that presses the linkage portion via the cam to move the linkage portion and the transport member in the intersection direction,
wherein a common driving source supplies a driving force that the transport member uses to transport the recording material, and a driving force for rotating the rotating member.
Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein:
Hereinafter, an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.
The image forming apparatus 100 of the exemplary embodiment is provided with an image forming unit 10 that forms a toner image on a sheet 50 which is an example of a recording material, and a sheet transporting system 30 that transports the sheet 50.
The image forming apparatus 100 is provided with a fixing device 43 that heats and applies pressure to the sheet 50 having the toner image formed by the image forming unit 10, thereby fixing the toner image on the sheet 50. The image forming apparatus is provided with a controller 41 that includes a CPU which is program controlled, and that controls each unit of the image forming apparatus 100. The image forming apparatus is provided with an image process unit 42 that processes image data output from a PC or a scanner.
The image forming unit 10, an example of image forming unit, is provided with a photosensitive drum 11; a charging unit 12; an exposure unit 13; a developing device 14; a transfer unit 15; and a cleaning unit (not illustrated).
The photosensitive drum 11 includes a photosensitive layer on an outer circumferential surface thereof, and rotates in the arrow direction in
The developing device 14 develops the electrostatic latent image formed on the photosensitive drum 11 with a toner, thereby forming a toner image on the photosensitive drum 11. The transfer unit 15 is disposed to face the photosensitive drum 11, and a transfer portion 18 is formed between the transfer unit 15 and the photosensitive drum 11. In the transfer portion 18, the toner image formed on the photosensitive drum 11 is electrostatically transferred onto the sheet 50 that is transported by the sheet transporting system 30. The cleaning unit (not illustrated) removes the remaining toner and the like from the photosensitive drum 11 after the transfer process is completed.
The fixing device 43 is disposed downstream of the image forming unit 10 in a transport direction of the sheet 50. The fixing device 43 is provided with a pair of roll-like members 43A and 43B which are in press contact with each other. The fixing device 43 is provided with a heating source (not illustrated) such as a halogen heater. The fixing device 43 heats and applies pressure to the sheet 50 that holds the toner image, and thus fixes the toner image on the sheet 50.
The sheet transporting system 30 is provided with an accommodating unit 31 that accommodates the sheet 50 therein; a feed roller 32 that feeds the sheet 50 out of the accommodating unit 31; and a feed roller 33 that separates and transports the sheets 50 fed by the feed roller 32 one by one.
The sheet transporting system 30 is provided with a sheet transport path 34 via which the feed roller 33 separates and transports the sheets 50 one by one. The sheet transport path 34 is formed so as to reach a sheet discharge port 60 provided in an upper portion of the image forming apparatus 100, via the imaging forming unit 10. The sheet transporting system. 30 is provided with a registration roll 35 that transports the sheet 50 to the transfer portion 18.
A discharge roll 52, an example of a transport member, is provided downstream of the fixing device 43 in the transport direction of the sheet 50. The discharge roll 52 transports the sheet 50 transported from an upstream side thereof to the sheet discharge port 60, and discharges the sheet 50 out of the image forming apparatus 100. Accordingly, in the exemplary embodiment, the sheets 50 stack on a sheet stacking surface 38 that is provided in the upper portion of the image forming apparatus 100.
In the exemplary embodiment, a follower roll 51 is provided in such a manner that the follower roll 51 is pushed against the discharge roll 52, and is driven to rotate by the discharge roll 52. The image forming apparatus 100 is provided with a motor M as a driving source that rotates the discharge roll 52.
In the exemplary embodiment, the image forming apparatus 100 is provided with a roll moving mechanism 200 that moves the discharge roll 52 and the follower roll 51 in a direction (a direction orthogonal to (intersecting) the sheet surface of
In the exemplary embodiment, a re-transport unit 2 is provided, and enables an image to be formed on both surfaces of the sheet 50. When an image is formed on both surfaces of the sheet 50, the sheet 50 passing through the fixing device 43 is again fed upstream of the transfer portion 18 via the re-transport unit 2. Thereafter, the sheet 50 passes through the transfer portion 18.
At this time, the front and back surfaces of the sheet 50 are inverted, and in the transfer portion 18, a toner image is transferred onto an opposite surface of a surface on which the image is already formed. Thereafter, the sheet 50 is discharged out of the image forming apparatus 100 via the fixing device 43.
A basic operation of the image forming apparatus 100 will be described.
First, image data formed in a personal computer (not illustrated) or the like is input to the image process unit 42 in order for an image to be formed in the image forming apparatus 100. The image process unit 42 processes the input image data in a predetermined manner. The processed image data is output to the exposure unit 13.
The exposure unit 13 receiving the image data selectively exposes the photosensitive drum 11 to light, the photosensitive drum 11 being charged to a predetermined potential by the charging unit 12, thereby forming an electrostatic latent image on the outer circumferential surface of the photosensitive drum 11. For example, the developing device 14 develops the formed electrostatic latent image into a black (K) toner image.
In contrast, coincident with the formation of the image, the feed roller 32 in the sheet transporting system 30 rotates, and the sheet 50 is supplied from the accommodating unit 31 to the sheet transport path 34. The sheet 50, which the feed roller 33 separates one by one, is transported to the registration roll 35, and is stopped for the moment.
Thereafter, coincident with the rotation of the photosensitive drum 11 having the toner image formed thereon, the registration roll 35 rotates, and the sheet 50 is transported to the transfer portion 18. In the transfer portion 18, the toner image formed on the photosensitive drum 11 is transferred onto the sheet 50. Thereafter, the fixing device 43 fixes the transferred toner image on the sheet 50, and then the discharge roll 52 discharges the sheet 50 onto the sheet stacking surface 38.
As illustrated in
In the exemplary embodiment, while the sheet 50 is nipped between the elastic member 522 and the follower roll 51 (refer to
In the exemplary embodiment, as illustrated in
A supporting member 53 is provided to support the rotating shaft 521. A coil spring 54 for a roll, an example of biasing unit, is provided between the supporting member 53 and the receiving gear 523, and biases the discharge roll 52 in an upper left direction in
In the exemplary embodiment, the receiving gear 523 receives a rotating driving force from the supply gear 524, thereby rotating the discharge roll 52 in a direction as illustrated by arrow 2A in
A sheet guide member 55 is not described above, but as illustrated in
The following is omitted in the description above, the follower roll 51 (refer to
In the exemplary embodiment, as illustrated in
A bearing 70 is provided between the fixed portion 551 and the rotating shaft 521 of the discharge roll 52, and thus the sheet guide member 55 does not rotate when the discharge roll 52 rotates. In the exemplary embodiment, since the bearing 70 is fixed to the rotating shaft 521, when the sheet guide member 55 moves in the orthogonal direction as described above, the discharge roll 52 also moves in the orthogonal direction along with the sheet guide member 55.
Here, as illustrated in
The sheet guide member 55 is provided with a first protruding piece 553 that protrudes from one end of the guide member body 552 in a longitudinal direction of the guide member body 552. The first protruding piece 553 is disposed along the direction orthogonal to the transport direction of the sheet 50, and is disposed along the extended line of the guide member body 552.
The sheet guide member 55 is provided with a second protruding piece 554 that protrudes from the first protruding piece 553. The second protruding piece 554 protrudes in a direction orthogonal to an extension direction of the first protruding piece 553.
Subsequently, the configuration of the roll moving mechanism 200 will be described.
As illustrated in
Here, as illustrated in
The push-out member 75 includes a cam surface (a cam) 75B that pushes out the second protruding piece 554 provided in the sheet guide member 55. The cam surface 75B is provided on the circumference of the rotating shaft 75A. In addition, the cam surface 75B is helically disposed on the circumference of the rotating shaft 75A.
The following is omitted in the description above, but in the exemplary embodiment, opposite ends of the push-out member 75 in its axial direction are supported by a supporting member 98.
As illustrated in
In the exemplary embodiment, as illustrated in
Hereinafter, detailed description will be given with reference to
More specifically, in the exemplary embodiment, the cam surface 75B is formed only on an upstream side of the push-out member 75 in a movement direction of the discharge roll 52, and when the second protruding piece 554 functioning as a linkage portion reaches a downstream side of the cam surface 75B, the second protruding piece 554 reaches the non-formation region. Accordingly, the second protruding piece 554 moves in an opposite direction of the movement direction of the discharge roll 52 (a detailed description will be given later).
Subsequently, the coaxial member 80 will be described.
As illustrated in
Referring to
In the exemplary embodiment, when the imparting spring 95 imparts a rotating force to the coaxial member 80, the solenoid 90 is turned on, and the flapper 91 (refer to
The following is omitted in the description above, but in the exemplary embodiment, as illustrated in
In contrast, when the solenoid 90 is turned on, and the flapper 91 moves toward the body of the solenoid 90, as illustrated in
A missing tooth portion 81B is provided on an outer circumferential surface of the missing tooth gear portion 81, and teeth are not formed in the missing tooth portion 81B. The gear portion 81A is provided in locations other than the missing tooth portion 81B of the missing tooth gear portion 81, and is provided with a gear (teeth).
When the solenoid 90 is not turned on, and the flapper 91 is hooked onto the protruding portion 82A, as illustrated in
Here, the missing tooth gear portion 81 functions as shut off unit. When the discharge roll 52 does not move in the axial direction (a detailed description will be given later), the missing tooth gear portion 81 shuts off a rotating driving force transmitted from the receiving gear 523 to the push-out member 75. Accordingly, the push-out member 75 does not rotate, and the discharge roll 52 does not move.
In contrast, as illustrated in
Here, the motion of the discharge roll 52 and the like when the solenoid 80 is turned on and the coaxial member 80 makes one rotation will be described with reference to
As described above, when the solenoid 90 is turned on, the coaxial member 80 starts rotating. In connection with the rotation of the coaxial member 80, the push-out member 75 rotates in a direction illustrated by arrow 2B in
Accordingly, as illustrated by arrow 2C in
When the rotation angle of the push-out member 75 reaches a predetermined angle, contact between the cam surface 75B and the sheet guide member 55 (the second protruding piece 554 of the sheet guide member 55) is released. In other words, in the exemplary embodiment, when the discharge roll 52 pressed by the cam surface 75B reaches a predetermined location, the second protruding piece 554 reaches the non-cam region 79 (refer to
Thereafter, since the discharge roll 52 is pressed by the coil spring 54 for a roll which functions as the biasing unit, the discharge roll 52 moves in an opposite direction of the direction in which the discharge roll 52 is pressed to move by the cam surface 75B. Accordingly, the discharge roll 52 returns to its original position at which the push-out member 75 is located before being pushed out. In the exemplary embodiment, when the discharge roll 52 moves in the opposite direction, the second protruding piece 554 passes through the non-cam region 79.
Here, in the exemplary embodiment, the discharge roll 52 moves in the orthogonal direction of the transport direction of the sheet 50 in this manner. Accordingly, when the discharge roll 52 moves with the sheet 50 nipped between the discharge roll 52 and the follower roll 51, the stacking position of the sheet 50 becomes offset. In other words, in the exemplary embodiment, it is possible to perform a so-called offset operation in which the sheets 50 are split in the direction intersecting the transport direction of the sheet, and then are discharged. When the stacking position of the sheet 50 becomes offset as in the exemplary embodiment (when it is possible to perform an offset operation), it is possible to simply sort the sheets 50 (the sheets 50 that stack on the sheet stacking surface 38) having an image formed thereon.
In the exemplary embodiment, the length of the receiving gear 523 in the axial direction of the discharge roll 52 (in the moving direction of the discharge roll 52) is set to be greater than the amount of offset of the discharge roll 52. Accordingly, even when the discharge roll 52 moves in the axial direction, contact between the supply gear 524 and the receiving gear 523 is maintained.
Here, the motion of the sheet 50 when the discharge roll 52 moves (when an offset operation is performed) will be described with reference to
As described above and illustrated in
In the exemplary embodiment, when the trailing edge detecting sensor 5 detects the trailing edge portion of the sheet 50, and then a predetermined period of time elapses, as illustrated in
In the exemplary embodiment, as described above, since the second cam surface B2 (refer to
Subsequently, in the exemplary embodiment, the trailing edge portion of the sheet 50 comes out of the discharge roll 52, contact between the second cam surface B2 and the sheet guide member 55 (the second protruding piece 554 of the sheet guide member 55) is released, and as illustrated in
Here, in the exemplary embodiment, as described above, before the trailing edge portion of the sheet 50 comes out of the discharge roll 52, the discharge roll 52 is set to stop. Accordingly, the stacking position of the sheet 50 becomes stable.
When the sheet 50 comes out of the discharge roll 52 in the middle of the movement of the discharge roll 52, the sheet 50 moves in the orthogonal direction due to an inertia force being imparted in the orthogonal direction of the transport direction of the sheet 50. At this time, the stacking position of the sheet 50 is likely to be unstable. In contrast, in the exemplary embodiment, an inertia force being imparted in the orthogonal direction of the transport direction of the sheet 50 is unlikely to be imparted to the sheet 50, and the stacking position of the sheet 50 becomes stable.
In the exemplary embodiment, electrical power required to move the discharge roll 52 decreases. In other words, power consumption required for an offset process of the sheet 50 decreases.
In the related art, a dedicated moving motor is prepared to move the discharge roll 52, and moves the discharge roll 52. At this time, power consumption increases by the amount of electric power required to drive the moving motor. In contrast, in the exemplary embodiment, the dedicated motor is not used to move the discharge roll 52, but the motor M (refer to
In the exemplary embodiment, since the dedicated motor is not prepared, the number of motors decreases, and thus costs are reduced.
When the dedicated motor is used, a sensor (a sensor for detecting a home position) for detecting the position of the discharge roll 52 is also required to be prepared. However, in the configuration of the exemplary embodiment, the sensor is not provided, and for this reason, costs are reduced.
In the exemplary embodiment, a driving force is transmitted, from the common motor M to each of the discharge roll 52 and the push-out member 75, thereby rotating the discharge roll 52 and the push-out member 75. However, when a rotating driving force is transmitted to each of the discharge roll 52 and the push-out member 75, first, the rotating driving force is transmitted from, the motor M to the discharge roll 52. More specifically, a rotating driving force is transmitted to the receiving gear 523 (an example of a driving force reception portion) that is attached to the discharge roll 52.
Subsequently, in the exemplary embodiment, a rotating driving force is transmitted from the receiving gear 523 to the push-out member 75. Accordingly, the driving force transmission mechanism becomes simplified.
Here, For example, a configuration may be also considered in which a driving force transmission path branches upstream of the receiving gear 523, and a driving force is supplied via a branching portion to each, of the receiving gear 523 and the push-out member 75. However, when the branches of the driving force transmission path are made, the driving force transmission mechanism is likely to become complicated. In contrast, since the exemplary embodiment has the configuration in which the branches of the driving force transmission path are not made, the driving force transmission mechanism becomes simplified.
In the exemplary embodiment, the moving speed of the discharge roll 52 is determined by the cam surface 75B. When the shape of the cam surface 75B is changed, the moving speed of the discharge roll 52 is changed.
When the inclined angle of the first cam surface B1 is set to be constant, the discharge roll 52 moves at a constant speed. Here, when the discharge roll 52 moves at a constant speed, a stacking disturbance of the sheets 50 already stacked on the sheet stacking surface 38 is unlikely to occur.
When the sheets 50 are discharged on the sheet stacking surface 38, a lot of the sheets 50 (hereinafter, referred to as “stacked sheets 50”) are already stacked on the sheet stacking surface 38. At this time, the sheets 50 to be discharged (hereinafter, referred to as “discharged sheets 50”) slide along over the stacked sheets 50.
When the discharge roll 52 moves at a constant speed in these conditions, the discharged sheet 50 moves over the stacked sheets 50 at a constant speed. At this time, the discharged sheet 50 is prevented from imparting a changing load (a frictional force) to the stacked sheets 50, and a stacking disturbance of the stacked sheets 50 is unlikely to occur, compared to when the load changes.
In the example illustrated in
More specifically, in the exemplary embodiment, as described above, before the sheet 50 comes out of the discharge roll 52, the discharge roll 52 stops moving temporarily. Immediately before the discharge roll 52 stops moving, the moving speed of the discharge roll 52 decreases.
Accordingly, when the sheet 50 comes out of the discharge roll 52, the shaking (rattling) of the sheet 50 decreases, and the posture of the sheet 50 is prevented from being disturbed. When the discharge roll 52 suddenly stops moving while moving at a high moving speed, the discharge roll 52 shakes immediately after the stop, thereby causing the shaking (rattling) of the sheet 50. As in the exemplary embodiment, when the moving speed of the discharge roll 52 decreases, the shaking of the sheet 50 decreases, and the posture of the sheet 50 is unlikely to become disturbed.
In the exemplary embodiment, while the push-out member 75 makes one rotation, it is necessary to move the discharge roll 52 by a predetermined amount (a predetermined amount of offset). For this reason, when the rear half portion of the first cam surface B1 is set to have a small inclined angle, it is necessary to set the inclined angle of a first half portion of the first cam surface B1 to be large. At this time, as illustrated in
Others
In the description above, the image forming apparatus 100 using a so-called electrophotography is exemplified, but each of the above-mentioned configurations described above may be applied to an image forming apparatus using other methods such as an ink jet head method.
In the exemplary embodiment, the image forming apparatus 100 is described as an example, but the application of the above-mentioned configurations is not limited to the image forming apparatus 100. Each of the configurations may be applied to a sheet transporting device that offsets and transports the sheet 50.
The image forming apparatus 100 as an example which is provided with only one of the photosensitive drums 11 and forms a monochromatic image is described above. However, the present invention may be applied to the image forming apparatus 100 that forms a color image, for example, a so-called tandem image forming apparatus in which plural photosensitive drums 11 are disposed in parallel.
In the description above, the motion of the push-out member 75 is switched between a rotation and a stop by using the coaxial member 80 (the missing tooth gear portion 81) and the solenoid 90. However, the motion of the push-out member 75 may be switched between a rotation and a stop by using an electromagnetic clutch, a torque limiter, and the like.
In the description above, the discharge roll 52 moves in the axial direction (a reciprocating motion of the discharge roll 52) due to the push-out member 75 and the coil spring 54 for a roll. However, the push-out member 75 illustrated in
The push-out member 75 rotates about a rotating shaft illustrated by dotted line 9B in a direction illustrated by arrow 9A in
The first push-out member 75C and the second push-out member 75D are disposed in a line in the axial direction, and a gap 75E is formed between the first push-out member 75C and the second push-out member 75D. A linkage portion 520 is disposed in the gap 75E, and is linked with the discharge roll 52. Here, the gap 75E includes a first helical portion 75F from the left to the right in
Here, the first helical portion 75F forms a helical shape in a clockwise direction when advancing from the left to the right in
In contrast, the second helical portion 75G forms a helical shape in a counter-clockwise direction when advancing from the left to the right in
The first helical portion 75F and the second helical portion 75G are formed so as not to intersect each other.
A helical cam surface (cam) 75B1 is provided in the first push-out member 75C at a location facing the first helical portion 75F. Similar to the first helical portion 75F, the cam surface 75B1 advances from the left to the right in
Here, for example, when the push-out member 75 starts rotating while the linkage portion 520 is positioned at a location illustrated by a reference sign 9D, the linkage portion 520 is pushed out by the cam surface 75B1 provided in the first push-out member 75C, and the linkage portion 520 moves in a direction illustrated by arrow 9E in
In the example illustrated in
The foregoing description of the exemplary embodiments of the present invention has been provided for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations will be apparent to practitioners skilled in the art. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with the various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2014-064741 | Mar 2014 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20020084572 | Kim | Jul 2002 | A1 |
| 20110187048 | Massoud | Aug 2011 | A1 |
| Number | Date | Country |
|---|---|---|
| 0524535 | Jan 1993 | EP |
| A-3-42460 | Feb 1991 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20150277331 A1 | Oct 2015 | US |
