JP2003176042A - Sheet supplying device, and image forming device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve setting operability of sheets in a state where a movable mechanism is disposed in a sheet feeding member disposed in a sheet tray. <P>SOLUTION: A sheet supplying device has the sheet feeding member 5 having the movable mechanism 7. The movable mechanism 7 is disposed in the sheet tray 1, is disposed facing to the surface of the sheets 2 stored in the sheet tray 1, and is movable between a feedable position where the mechanism contacts with the uppermost sheet of the sheets 2 stored in the sheet tray 1 and feeds the sheets and an evacuated position separated from the feedable position. The movable mechanism 7 is positioned at the evacuated position in a sheet set state of the sheet tray 1, or at the feedable position in a sheet feed state of the sheet tray 1. An image forming device having the sheet supplying device is provided. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device for feeding a sheet such as a sheet to an image forming portion of an image forming apparatus such as a copying machine or a printer, and more particularly, to a sheet feeding unit or a sheet feeding unit. The present invention relates to a sheet supply device having a part and an improvement of an image forming apparatus using the same.

[0002]

2. Description of the Related Art Generally, in an image forming apparatus such as a copying machine or a printer, an image formed by an image forming unit is transferred onto a sheet such as a sheet, and therefore, it is usually performed.
A sheet feeding device that feeds a sheet to the image forming unit is provided. Conventionally, this type of sheet feeding device has a sheet tray for accommodating sheets, and for example, a sheet feeding member (for example, a pickup roll) that contacts the sheet and feeds the sheet to a sheet feeding path is provided in the sheet tray. ) And a mechanism for separating the delivered sheets one by one (for example, composed of a feed roll and a retard roll)
And a sheet feeding unit including the sheet feeding unit. This sheet feeding unit is provided in the image forming apparatus main body, and after the sheet tray is inserted into the image forming apparatus main body, the sheet feeding member constituting the sheet feeding unit comes into contact with the uppermost sheet among the sheets accommodated in the sheet tray. In general, the sheet is sent out by a sheet. However, when the sheet feeding unit is provided in the main body of the image forming apparatus, the sheet feeding member and the sheet accommodated in the sheet tray may come into contact with each other when the sheet tray moves in and out, and the position of the set sheet may move. Must be avoided. For that purpose, it is necessary to form a gap to some extent between the sheet feeding member and the uppermost sheet, which causes a disadvantage that the image forming apparatus must be designed large in designing the image forming apparatus. As a sheet feeding device that has improved this inconvenience,
By providing all or a part of the sheet feeding unit on the sheet tray side, when the sheet tray is moved in and out, the sheets accommodated in the sheet tray and at least the sheet feeding member constituting the sheet feeding unit move integrally with the sheet tray. The mode of doing is already known. According to this aspect, since the sheet delivery member is provided on the sheet tray side, it becomes possible to uniquely set the relative positional relationship between the sheet accommodated in the sheet tray and the sheet delivery member, and the image forming apparatus main body is provided. This is preferable in that it is not necessary to form a gap for preventing interference with the sheet feeding apparatus, and the image forming apparatus can be designed small.

[0003]

However, when the sheet feeding member is provided in the sheet tray, there is a new technical problem that the sheet feeding member interferes with the setting of the sheet and it is difficult to set the sheet. Found in. In particular, when the form of the sheet delivery member is a roll, the contact pressure between the roll and the sheet fluctuates depending on the load of the sheet, and therefore the pair of rolls is considered to have better performance than a single roll. In such a case, the technical problem described above becomes more prominent because the obstructive area is expanded. As a means for solving such a technical problem, in a sheet feeding device in which a sheet feeding member is provided on the sheet tray side, a mode in which the sheet feeding member is rotatably provided so as to manually swing is proposed. (For example, JP-A-6
No. 1-119536). According to this aspect, it is possible to swing the sheet delivery member to a position deviated from the sheet stacking position when setting the sheet, and the sheet can be easily set without the sheet delivery member getting in the way. May. However, in this aspect, it is indispensable for the user to manually swing the sheet sending member when setting the sheet, and there is a technical problem that the sheet setting operability is significantly reduced.

The present invention has been made to solve the above technical problems, and improves the operability of setting a sheet in a mode in which a movable mechanism is provided in a sheet feeding member provided in a sheet tray. The present invention provides a sheet supply device capable of achieving the above and an image forming apparatus using the same.

[0005]

That is, according to the present invention, as shown in FIG. 1, a sheet 2 is accommodated and can be drawn out between a sheet feed position of a sheet tray 1 and a sheet set position of a sheet tray 1. Sheet tray 1 provided
And a sheet feeding unit 4 for feeding the sheets 2 accommodated in the sheet tray 1 in order from above. In the sheet feeding unit 4, the sheet feeding unit 4 is provided on the sheet tray 1 side and At least a sheet delivery member 5 arranged to face the accommodated sheet 2 mounting surface is provided, and the sheet delivery member 5 is movably provided between a feedable position and a retracted position, while the sheet tray 1 of the sheet tray 1 is provided. The sheet feeding member 5 is at the sheet setting position.
Is disposed at the retracted position, and the movable mechanism 7 is provided at the sheet feed position of the sheet tray 1 so that the sheet delivery member 5 is disposed at the feedable position.

In such technical means, the sheet setting position means the position of the sheet tray 1 in a state where the sheet tray 1 is pulled out from the image forming apparatus main body and the sheet 2 can be set. The sheet feed position means the position of the sheet tray 1 in a state where the sheet tray 1 is completely inserted into the main body of the image forming apparatus and the sheet 2 can be delivered by the sheet delivery unit 4.

As a typical mode of the sheet delivery unit 4, there is one provided with a sheet delivery member 5 for delivering the sheets 2 and a separating and separating mechanism 6 for separating the delivered sheets 2 one by one. Here, the sheet delivery member 5 may be a roll itself or a mode in which a belt is stretched between two or more rolls, and the separating mechanism 6 may be a roll or belt-shaped feed member and Also, a combination with a retard member having a high surface friction resistance (roll, fixed pad, etc.) can be mentioned. Further, the sheet delivery member 5 is movable between the feedable position and the retracted position. At this time, the feedable position means the position of the sheet delivery member 5 when the sheet delivery member 5 comes into contact with the uppermost sheet of the sheets 2 accommodated in the sheet tray 1 and delivers the sheet, and is retracted. The position means a position separated from the feedable position where the sheet sending member 5 does not interfere when the sheet 2 is set. Further, in the illustrated example, in order to reliably guide the sheet 2 delivered by the sheet delivery member 5 to the separating mechanism 6, the leading end guide 3 is inclined toward the separating mechanism 6, and the sheet tray 1 is moved in and out. In order to prevent the sheet 2 from moving, the rear end side of the sheet 2 is held by the end guides 3a that are slanted. A mode in which the sheets 2 are stacked on the bottom plate disposed at the bottom of the sheet tray and the bottom plate is constantly pushed up and supported to keep the top sheet at a predetermined position may be used.

[0008] In such technical means, the movable mechanism 7 may change the position of the sheet feeding member 5 between the feedable position and the retracted position separated from the feedable position. It is preferable that the sheet tray 1 is configured as a mechanism that mechanically or electrically interlocks with the movement of the sheet tray 1. According to the movable mechanism 7, the sheet 2 can be easily set without the sheet sending member 5 getting in the way when the sheet is set. Further, since the sheet delivery member 5 can be automatically set in association with the movement of the sheet tray 1, no special operation for moving the position of the sheet delivery member 5 is required, and the operability of setting the sheet 2 is greatly improved. Improve to.

Further, in the present invention, the sheet sending member 5 is movable at the sheet setting position of the sheet tray 1 to a second retracted position further separated from the retracted position. Here, the moving mechanism of the sheet delivery member 5 may be manually operated,
It may be a mechanism that moves automatically. Sheet tray 1
In the sheet setting position of 1, the sheet delivery member 5 is movably provided to the second retracted position, so that the sheet delivery member 5 is further retracted from the sheet 2 mounting surface accommodated in the sheet tray 1, so that the user can When setting the seat 2, a wider seat setting space can be secured, and the operability of setting the seat 2 is improved. In particular, when a large number of sheets 2 are set, a wide sheet setting space is required, so the present invention is extremely effective.

Further, in the present invention, when the sheet delivery unit 4 is provided with the sheet delivery member 5 for delivering the sheets 2 and the separating mechanism 6 for separating the delivered sheets 1 one by one, the separating mechanism 6 is provided. In order to prevent an obstacle when setting the sheet, it is preferable that the separating mechanism 6 is arranged at a position outside the upper region of the sheet 2 mounting surface accommodated in the sheet tray 1. If the separating mechanism 6 is arranged facing the upper region of the sheet 2 mounting surface, it is preferable that the movable mechanism 7 retracts the separating mechanism 6 together with the sheet feeding member 5.

Further, according to the present invention, the leading edge guide 3 is provided at a position corresponding to the feeding direction of the sheet 2 of the sheet tray 1 and is inclined in the feeding direction of the sheet 2 in the sheet feeding apparatus. Causes the sheet set to be defective in that the sheet slides along the inclined surface of the tip guide 3. Therefore, a position regulating member that is provided separately from the leading end guide 3 and that regulates the position of the end face of the sheet 2 by contacting the end face of the sheet 2 in the delivery direction is provided. The member is arranged so as to project toward the sheet 2 side, and at the sheet feed position of the sheet tray 1, the front end guide 3 is placed more than the position regulating member in the sheet 2 position.
It may be arranged so as to project to the side. Here, as typical examples of the position regulating member, there are a high-friction member that regulates the sheet position by frictional resistance, and an elastic member such as a sponge that regulates the sheet position by biting due to elasticity.

The addition of the position regulating member regulates the sheet edge position. Further, since the position regulating member is operated at the sheet setting position of the sheet tray 1 and the leading end guide 3 is operated at the sheet feeding position of the sheet tray 1, the sheet is guided along the inclined surface of the leading end guide 3 during the sheet setting operation. It is possible to improve the sheet setting failure such that the sheet slides, and it is possible to reliably secure the sheet guide performance during sheet feeding. For this reason, it is possible to effectively separate the sheet setting operability and the sheet guide transportability according to the position of the sheet tray, thereby achieving both performances.

Further, the present invention is not limited to the sheet feeding apparatus, but also an image forming apparatus provided with the sheet feeding apparatus.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail based on the embodiments shown in the accompanying drawings. First Embodiment FIG. 2 shows a first embodiment of an image forming apparatus including a sheet feeding device to which the present invention is applied. In the figure, the image forming apparatus is equipped with, for example, an electrophotographic image forming engine 50 in the image forming apparatus main body 10, and is equipped with a sheet feeding device 55 below the image forming engine 50 in the apparatus main body 10. The upper portion of the apparatus main body 10 is configured as a discharge tray 56, and the sheet 21 sent from the sheet supply device 55 to the back side (corresponding to the left side in FIG. 2) in the apparatus main body 10 is sent to the image forming engine 50 and the discharge tray 56. Leading sheet supply path 5
7 is provided in a substantially vertical direction.

In the present embodiment, the image forming engine 50.
Is the photosensitive drum 51 and the charged photosensitive drum 51.
An exposure device 5 such as a laser scanning device that writes an electrostatic latent image on it
2, a transfer device 53 for transferring a visible image (toner image) on the photosensitive drum 51 to the sheet 21, and a fixing device 54 for fixing the unfixed image transferred on the sheet 21. An electrophotographic device (not shown) such as a charging device for charging the photosensitive drum 51 and a cleaning device for cleaning the residual toner on the photosensitive drum 51 is arranged around the photosensitive drum 51. Also, sheet supply path 5
7, a registration roll 58 for positioning and conveying the sheet 21 is provided on the upstream side of the photosensitive drum 51, and a registration roll sensor 581 for detecting the position of the sheet 21 is provided on the front side of the registration roll 58. ing.

Further, in the present embodiment, as shown in FIGS. 2 and 3, the sheet feeding device 55 accommodates the sheet 21 and is arranged so as to be drawn out from the tray receiving portion of the apparatus main body 10. A sheet tray 20 is provided. Also, as shown in FIG.
Has a sheet storage portion 26 in which sheets are stacked and stored. The sheet storage portion 26 is partitioned by a front end guide (lead guide) 23, an end guide 22, and a side guide 25. Here, the leading end guide 23 is a plate-shaped member extending in the width direction of the sheet tray, and positions the end of the sheet 21 in the feeding direction and reliably guides the sheet 21 fed by the pickup roll 31 to the position of the separating mechanism 32. To
It is arranged so as to be inclined toward the separating mechanism 32. The end guide 22 positions the end of the sheet 21 on the side opposite to the feeding direction, and the side guide 25 positions the end of the sheet 21 in the width direction.

Further, in this embodiment, the sheet tray 2
As shown in FIG. 3, 0 is attached to the image forming apparatus main body 10 so as to be freely drawn out between the sheet set position and the sheet feed position. Here, the sheet setting position means the position of the sheet tray 20 when the sheet tray 20 is pulled out from the image forming apparatus main body 10 and the sheets 21 can be set (see FIG. 3A).
The sheet feed position means the position of the sheet tray 20 in a state where the sheet tray 20 is completely inserted into the image forming apparatus main body 10 and the sheet 21 can be delivered by the sheet delivery unit 30 (see FIG. 3B). (See reference).

Further, a sheet delivery unit 30 is arranged above the sheet tray 20 on the sheet delivery direction side. The sheet feeding unit 30 includes a sheet tray 2
A pickup roll 31 arranged to face the sheet 21 mounting surface accommodated in 0, and at least a part of which is placed in contact with the sheet 21 at the sheet feed position of the sheet tray 20, and a sheet delivered by the pickup roll 31. It is provided with a separating mechanism 32 for separating 21 one by one. In the present embodiment, as shown in FIG. 4, the support structure of the pickup roll 31 includes a support rod 312 in the vicinity of the separating mechanism 32 of the sheet tray 20 and the sheet tray 20.
Over the width direction of the support rod 312, a holding arm 311 is swingably provided at substantially the center of the support rod 312, and a pickup roll 31 (a pair in this example) is rotatably provided at the swing-free end of the holding arm 311. It is provided. Then, the driving force from a motor (not shown) is transmitted to the pickup roll 31 via a drive transmission gear 313 composed of a plurality of gear trains. Further, the judgment mechanism 32
Is disposed at a position outside the upper region of the sheet 21 mounting surface accommodated in the sheet tray 20, and includes a feed roll 321 and a retard roll 322 having a higher surface resistance than the feed roll 321. There is.

In the present embodiment, the pickup roll 31 is movably provided between the feedable position and the retracted position. Here, the feedable position refers to a pickup roll when the pickup roll 31 comes into contact with the uppermost sheet of the sheets 21 accommodated in the sheet tray 20 and sends out the sheet 21, as shown in FIG. As shown in FIG. 6B, the retracted position means that the holding arm 311 is arranged parallel to the sheet 21 mounting surface accommodated in the sheet tray 20 and is picked up when the sheet 21 is set. It means a position separated from the feedable position where the roll 31 does not interfere.

In particular, in this embodiment, the pickup roll 31 is interlocked with the movement of the sheet tray 20 in and out of the image forming apparatus main body 10 by the movable mechanism 90, as shown in FIGS. 5, 6 and 10. Between the sheet feeding position and the sheet setting position of the sheet tray 20 between the feedable position and the retracted position. Then, at the sheet feed position of the sheet tray 20, as shown in FIG. 5, the pickup roll 31 is arranged at a feedable position so that the pickup roll 31 contacts the sheet 21, and at the sheet setting position of the sheet tray 20, As shown in FIG. 6B, the pickup roll 31 is arranged at the retracted position so that the pickup roll 31 does not get in the way when the sheet 21 is set.

The movable mechanism 90 according to this embodiment is shown in FIG.
As shown in FIG. 3, a block 91 with a main body is provided on one side of the sheet tray 20 on the back side of the image forming apparatus main body 10, while a shallow inverted V-shaped lever 92 is provided on the side wall of the sheet tray 20. The rotary shaft 93 of the bent portion is swingably supported about the swing center, and one arm portion 94a of the lever 92 is provided over the block 91 with the main body so as to be able to pass over the block. Here, the other arm portion 9 of the lever 92
The tip of 4b is a biasing spring 95 (a compression spring in this example, but a tension spring may be used if the swing width of the lever 92 is large) on a pedestal 96 provided at the bottom of the sheet tray 20. Energized and supported. In addition, a locking projection 97 that projects upward is provided near the tip of the other arm 94b.
An inclined portion 971 is formed on the right side in a state of descending to the side away from the rotating shaft 93. Further, the pedestal 96 is provided with a stopper 98 that regulates the upper end position of the tip of the other arm portion 94b. In addition, the movable mechanism 90
Is provided with a roll-side lever 99 that extends to the opposite side of the holding arm 311 with the support rod 312 interposed therebetween on the base end side of the holding arm 311. An engaging protrusion 100 that protrudes downward is provided on a part of the roll-side lever 99, and the engaging protrusion 100 has a right-down inclined portion 101 and a locking receiving portion adjacent thereto. And a section 102 are provided. At the sheet setting position of the sheet tray 20, the locking receiving portion 102 of the engaging projection 100 is the locking projection 9 described above.
It is designed to latch with 7. Further, in the main body 10 of the image forming apparatus, a guide 12 with a main body, which is long in the horizontal direction along the direction in which the sheet tray 20 moves in and out, is provided at a portion corresponding to the roll-side lever 99. An inclined portion 13 having an upper right shape is provided on the back side of 12.

In such a movable mechanism 90, as shown in FIG. 5, at the sheet feeding position of the sheet tray 20, the pickup roll 31 comes into contact with the uppermost sheet of the sheets 21 accommodated in the sheet tray 20 and the sheet 21. The pick-up roll 31 is arranged at a feedable position so that the paper can be delivered to the separating mechanism 32. On the other hand, when pulling out the sheet tray 20 from the image forming apparatus main body 10, as shown in FIG.
The upper portion of 9 contacts the inclined portion 13 of the body-equipped guide 12, the roll-side lever 99 descends along the inclined portion 13, and the locking projection 97 of the lever 92 and the engagement projection 100 of the roll-side lever 99. The pickup roll 31 is arranged at the retracted position by latching with the lock receiving portion 102 in the above. The details will be described later.

Further, in the present embodiment, at the sheet setting position of the sheet tray 20, as shown in FIG. 7, the holding arm 311 is swingably provided around the support rod 312, and the pickup roll 31 is provided.
Are arranged at a second retracted position further separated from the feedable position. The second retracted position may be set at any position as long as it is a position separated from the feedable position. Further, although the holding arm 311 is manually operated in the present embodiment, it may be a mechanism that moves automatically.

Further, in the present embodiment, the sheet tray 2
As shown in FIG. 4, a position restriction block 24 for restricting the end surface position of the sheet 21 is provided at a position corresponding to the 0 sheet 21 feeding direction, as shown in FIG.
A plurality (two places in this example) are evenly arranged in the width direction of 0. On the other hand, a plurality of (two in this example) rectangular openings 231 in which the position regulation block 24 can freely appear and disappear are provided in a portion of the leading end guide 23 corresponding to the position regulation block 24 at the sheet feed position of the sheet tray 20. Has been. On the other hand, the position regulation block 24 includes a block main body 241 having a substantially triangular cross section, and the block main body 241.
And a high friction member 242 attached to the inclined surface. Here, the inclined surface of the block body 241 has an inclination similar to that of the leading end guide 23, and the sheet tray 20
A high-friction member 242 is arranged so that it can slide in and out along a guide groove 46 (see FIG. 9) provided at the bottom of the high friction member 242 from the rectangular opening 231 of the tip guide 23. Further, in the present embodiment, an elastic member such as a sponge is used as the high friction member 242, but it is preferable in that the seat position can be regulated by the friction resistance and the seat position can be regulated by the biting by elasticity.

In particular, in this embodiment, the position regulating block 24 has the advancing / retreating mechanism 40 as shown in FIGS. 8 (a) and 8 (b).
9 (see FIG. 9), the sheet tray 20 is moved back and forth between the sheet set position and the sheet feed position in association with the movement of the sheet tray 20 in and out of the image forming apparatus main body 10. Then, at the sheet setting position of the sheet tray 20, as shown in FIG. 8A, the position regulating block 24 is arranged so as to project from the leading end guide 23 toward the sheet 21 side so that the position regulating block 24 contacts the sheet 21. At the sheet feed position of the sheet tray 20, as shown in FIG. 8B, the leading end guide 23 is arranged so as to project toward the sheet 21 side with respect to the position regulating block 24 so that the leading end guide 23 contacts the sheet 21, that is, in other words. , Position regulation block 2
4 is arranged so as to be retracted from the leading end guide 23 to the opposite side of the seat 21. As shown in FIGS. 9A and 9B, the advancing / retreating mechanism 40 according to the present embodiment has a rack 44 formed in a part of the block body 241 of the position regulation block 24, and is positioned near the block body 241. At the bottom of the sheet tray 20, there is provided a partial gear 42 having teeth partially engaging with the rack 44, and at a toothless portion of the partial gear 42, a projecting piece 43 projecting in the insertion direction of the sheet tray 20. On the other hand, the partial gear 4 is so arranged that the position regulation block 24 always returns to the position projectingly arranged toward the seat 21 through the rectangular opening 231 of the leading end guide 23.
2 is biased by a biasing spring 41. Furthermore,
The advancing / retreating mechanism 40 is provided with a stopper 11 provided on the image forming apparatus main body 10 when the sheet tray 20 is inserted.
The notch 45 is provided at a position corresponding to the stopper 11 of the sheet tray 20 so that the projection piece 43 and the projection piece 43 can contact each other.

In the advancing / retreating mechanism 40, as shown in FIG. 9A, at the sheet setting position of the sheet tray 20, the position regulating block 24 advances from the rectangular opening 231 of the leading end guide 23, and is moved from the leading end guide 23. Is also arranged so as to project toward the seat 21. On the other hand, when the sheet tray 20 is inserted into the image forming apparatus main body 10, as shown in FIG. 9B, the sheet tray 20 of the position regulation block 24 is inserted from the rectangular opening 231 provided in the leading end guide 23. By retracting in the direction, the tip guide 23 is arranged so as to project toward the sheet 21 side from the position regulation block 24 so that the tip guide 23 contacts the sheet 21, in other words, the position regulation block 24 retracts to the opposite side of the sheet 21 from the tip guide 23. It is supposed to be placed. The details will be described later.

Next, the operation of the image forming apparatus according to the present embodiment will be described focusing on the sheet feeding device. When accommodating and setting the sheets 21 in the sheet tray 20, the sheet tray 20 is pulled out from the image forming apparatus main body 10, and at the sheet setting position of the sheet tray 20, the end faces of the sheet 21 are aligned with the position regulating block 24 and the sheets 21 are set. It should be set as a housing. At this time, when the sheet tray 20 is pulled out from the image forming apparatus main body 10, as shown in FIG. 6A, the movable mechanism 90 causes the upper portion of the roll-side lever 99 to contact the inclined portion 13 of the main assembly guide 12. The roll-side lever 99 descends along the inclined portion 13. Further, the locking projection 97 of the lever 92 is pushed by the engaging projection 100 of the roll-side lever 99 that has descended,
2 descends along the urging force of the urging spring 95. At that time, the inclined portion 101 of the engagement protrusion 100 of the roll-side lever 99 slides up along the inclined portion 971 of the locking protrusion 97 of the lever 92, and the engagement of the lever 92 at the horizontal portion 14 of the main assembly guide 12 is performed. The stop projection 97 and the locking receiving portion 102 of the engagement projection 100 of the roll-side lever 99 latch. Further, the roll-side lever 99 that supports the own weight of the holding arm 311 tries to rotate counterclockwise due to this own weight, but the force of this rotation is applied to the lever 9
2 rotates clockwise against the urging force of the urging spring 95 and presses it at the position regulated by the stopper 98, while the roll-side lever 99 is restrained by the horizontal portion 14 of the body-attached guide 12 and the pickup roll 31 Is Figure 6
It will be arranged at the retracted position shown in (b). Therefore, the pickup roll 31 does not interfere with the seat 2
It becomes possible to set 1.

Further, when the sheet tray 20 is pulled out from the image forming apparatus main body 10, as shown in FIG. 9A, the advancing / retracting mechanism 40 releases the contact between the projecting piece 43 and the stopper 11, and the partial gear 42 is removed. It rotates clockwise along the urging force of the urging spring 41. By this rotation, the rack 44 that meshes with the partial gear 42 moves in the drawing direction of the sheet tray 20, and the position regulation block 24 moves the sheet tray 20.
It slides in the guide groove 46 provided at the bottom of the tip end and goes out from the rectangular opening 231 of the tip guide 23. That is, the position regulation block 24 is arranged so as to project toward the sheet 21 side with respect to the leading end guide 23 so that the position regulation block 24 contacts the sheet 21. Therefore, when accommodating and setting the seat 21, the position regulation block 24 contacts the seat 21, and the seat 21 does not slide along the inclined surface,
The accommodation setting operation of the seat 21 is easily performed.

Further, at the sheet setting position of the sheet tray 20, as shown in FIG. 7, the holding arm 311 can be swung upward around the support rod 312. Therefore, when a large number of sheets 21 are set, the holding arm 311 may be swung to arrange the pickup roll 31 at the second retracted position. The pickup roll 31 is retracted from the upper region of the sheet 21 mounting surface accommodated in the sheet tray 20, and a wider sheet setting space can be secured.

On the other hand, when the accommodation setting operation of the sheets 21 is completed, the sheet tray 20 may be inserted into the image forming apparatus main body 10 to the sheet feeding position. At this time,
As shown in 0 (a), one arm portion 9 of the lever 92
4a rides on the block 91 with the main body and rotates clockwise along the biasing force of the biasing spring 95. By this rotation, the locking projection 97 of the lever 92 and the roll-side lever 99
Of the engaging projection 100 is disengaged from the lock receiving portion 102, and the roll-side lever 99 rotates counterclockwise due to the own weight of the holding arm 311 and the holding arm 311.
Is lowered, and the pickup roll 31 is arranged at the feedable position shown in FIG. Therefore, the pickup roll 31 comes into contact with the sheet 21, and the sheet 21 can be delivered toward the separating mechanism 32.

At this time, as shown in FIG. 9B, the protruding piece 43 comes into contact with the stopper 11, and the partial gear 42 rotates counterclockwise against the urging force of the urging spring 41. By this rotation, the rack 44 that meshes with the partial gear 42 moves in the insertion direction of the sheet tray 20, the position regulation block 24 slides in the guide groove 46 provided in the bottom portion of the sheet tray 20, and the rectangular shape of the leading end guide 23. Opening 2
The sheet tray 20 is retracted from 31 in the insertion direction of the sheet tray 20. That is, the leading end guide 23 is arranged so as to project toward the sheet 21 side with respect to the position regulation block 24 so that the leading end guide 23 contacts the sheet 21, in other words, the position regulation block 24 is arranged backward with respect to the sheet 21 side relative to the leading end guide 23. . Therefore, the leading end guide 23 comes into contact with the end surface of the sheet 21, and the sheet 21 picked up by the pickup roll 31 can be guided and conveyed toward the separating mechanism 32.

The sheets 21 picked up by the pickup roll 31 are guided by the front end guide 23, and are separated by the separating mechanism 32 one by one. Further, as shown in FIG. 2, the sheet 21 sent from the sheet supply device 55 is conveyed upward through the sheet supply path 57, positioned by the registration roll 58, and then, the photosensitive drum 51 and the transfer device. The visible image (toner image) on the photosensitive drum 51 is transferred in the transfer nip region with 53, and then the fixing device 54 performs the fixing process, and the sheet is discharged to a discharge tray 56 through a discharge roll 59. To be done.

According to the present embodiment, the movable mechanism 90 for changing the position of the pickup roll 31 is interlocked with the movement of the sheet tray 20.
The position can be automatically set, and even in the sheet feeding device in which the pickup roll 31 is arranged on the sheet tray side, the user can set the sheet 21 without requiring a special operation. it can. Further, at the sheet setting position of the sheet tray 20, by further providing the position of the pickup roll 31 so as to be movable to the second retracted position, a large number of sheets 21 can be set without the pickup roll 31 being an obstacle. It becomes possible. Further, since the position regulating block 24 for regulating the sheet end position is added, the position regulating block 24 is made to work at the sheet setting position of the sheet tray 20, and the leading end guide 23 is made to work at the sheet feeding position of the sheet tray 20. In the sheet setting operation, it is possible to improve the sheet setting failure that the sheet 21 slides along the inclined surface of the leading end guide 23, and it is possible to reliably ensure the sheet guide performance during the sheet feeding. For this reason, it is possible to effectively separate the sheet setting operability and the sheet guide transportability according to the position of the sheet tray, thereby achieving both performances.

In the present embodiment, the tip guide 23 is provided in the shape of a plate, and the advancing / retreating mechanism 40 causes the position regulating block 24 to be projected / retracted from the rectangular opening 231 of the tip guide 23. However, it is formed in the shape of a plate. Alternatively, the position regulating plate and the block-shaped tip guide block may be provided, and the advancing / retreating mechanism may be reversed. Alternatively, the leading end guide block formed in a block shape may be fixedly arranged on the image forming apparatus main body 10, and the position regulating plate may be fixedly arranged on the sheet tray 20.

Second Embodiment FIG. 11 shows a second embodiment of the sheet feeding device used in the image forming apparatus to which the present invention is applied. In the figure,
The sheet feeding device according to the present embodiment is similar to the sheet feeding device according to the first embodiment, in that the sheet 2
The sheet tray 20 accommodating the image forming apparatus main body 1
The sheet feeding unit 3 is attached to the sheet tray 20 so that it can be pulled out freely.
0, but unlike the first embodiment, the seat 21
The seat 21 is lifted and supported by the bottom plate 200 without using the inclined front end guide 23 as a positioning mechanism.

In this embodiment, as shown in FIG. 11, the bottom plate 200 is provided at the bottom of the sheet tray 20.
This bottom plate 200 is disposed in contact with the bottom portion of the sheet tray 20 with one end serving as a pivot portion 201, and one or a plurality of locations (locations located on the sheet feeding direction side) distant from the pivot portion 201 ( In the figure, it is biased and supported by an elastic spring 202 (one example). Then, the bottom plate 200 is pushed obliquely upward by the elastic spring 202, and the sheet 21 stacked on the bottom plate 200 is pressed and arranged on the pickup roll 31. For this reason,
Since the distance between the sheet 21 pushed up by the bottom plate 200 and the installation position of the pickup roll 31 becomes shorter, the holding arm 203 of the pickup roll 31 in the present embodiment is shorter than that in the first embodiment. Has been. Further, in the present embodiment, as a positioning mechanism of the seat 21, the end plate is provided with an end guide on the side opposite to the sending direction with respect to the seat 21 which is obliquely arranged upward by the bottom plate 200 toward the sending direction side of the sheet 21. Positioning by 27 and seat 2
A method is used in which the widthwise end of 1 is positioned by a side guide (not shown). In the present embodiment, the delivery direction of the uppermost sheet 21 is directly directed to the nip area of the separating mechanism 32, and therefore the leading end guide 2 as in the first embodiment is used.
3 is unnecessary. Furthermore, this pickup roll 31
In the same manner as in the first embodiment, the movable mechanism 90 automatically moves between the feedable position and the retracted position in conjunction with the movement of the sheet tray 20 in and out of the image forming apparatus main body 10, and At the sheet setting position of the sheet tray 20, it is movably provided to the second retracted position.
The same components as those in the first embodiment are designated by the same reference numerals as those in the first embodiment, and detailed description thereof will be omitted here.

Therefore, in the case of the sheet feeding apparatus using the bottom plate lift system as in this embodiment,
When setting the sheet 21, it is necessary to align one end of the sheet 21 with the end guide 27 and let the other end of the sheet 21 go under the pickup roll 31 to set the sheet 21. Roll 31
Seat 2 that can be squeezed in by obstacles
The amount of 1 becomes smaller. However, according to the present embodiment,
By the movable mechanism 90, the pickup roll 31 is arranged at the retracted position at the sheet setting position of the sheet tray 20, so that the amount of the sheet 21 sunk in at the time of sheet setting is improved. Further, since the pickup roll 31 is movably provided to the second retracted position, the setting operation of the sheets 21 becomes smooth even when a large number of sheets 21 are set.

[0038]

As described above, according to the present invention,
In a sheet feeding device having a sheet feeding member on the side of the sheet tray, a movable mechanism that variably sets the position of the sheet feeding member according to the position of the sheet tray is provided, and when the sheet is set, the sheet feeding member is retracted from the feedable position. Since the sheet is returned to the feedable position during sheet feeding, the sheet can be easily set without disturbing the sheet feeding member when setting the sheet, and the position of the sheet feeding member is automatically set during sheet feeding. Can be set to. For this reason, it is possible to greatly improve the set operability of the sheet without requiring a special operation for moving the position of the sheet delivery member, and to always stabilize the sheet delivery operation by the sheet delivery member. be able to. Further, according to the image forming apparatus provided with such a sheet feeding device, it becomes possible to make the sheet setting operability and the stability of the sheet feeding operation compatible with each other, so that the reliability of the sheet feeding process is improved. An improved image forming apparatus can be provided.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an outline of a sheet feeding apparatus according to the present invention.

FIG. 2 is an explanatory diagram showing an outline of an image forming apparatus including the sheet feeding device according to the first embodiment.

FIG. 3 is an explanatory diagram showing a sheet setting position and a sheet feeding position of the sheet feeding device according to the present invention.

FIG. 4 is an explanatory diagram showing the sheet feeding device according to the first embodiment.

FIG. 5 is an explanatory diagram showing a state of the sheet feeding apparatus according to the first embodiment at a sheet feeding position.

FIG. 6A is an explanatory view showing a movable mechanism of the sheet feeding apparatus according to the first embodiment when the sheet tray is pulled out, and FIG.
FIG. 4 is an explanatory diagram showing a state of the sheet feeding device at a sheet setting position.

FIG. 7 is an explanatory diagram showing the operation of the sheet sending member at the sheet setting position of the sheet feeding apparatus according to the first embodiment.

FIG. 8A is an explanatory view showing a state of the tilt guide member and the position regulating member at the sheet setting position in the sheet feeding device according to the first embodiment, and FIG. 8B is a tilt guide member in the sheet feeding device; It is explanatory drawing which shows the state in the sheet feed position of a position control member.

9A is an explanatory view showing an advancing / retreating mechanism at the time of pulling out a sheet tray of the sheet feeding apparatus according to the first embodiment, FIG.
FIG. 7 is an explanatory view showing an advancing / retreating mechanism at the time of inserting a sheet tray of the sheet feeding apparatus.

FIG. 10A is an explanatory view showing a movable mechanism at the time of inserting the sheet tray of the sheet feeding apparatus according to the first embodiment,
FIG. 6B is an explanatory diagram showing a state of the sheet feeding device at a sheet feeding position.

FIG. 11 is an explanatory diagram showing a state at a sheet feeding position of the sheet feeding device according to the second embodiment.

FIG. 12A is an explanatory diagram showing a movable mechanism of the sheet feeding apparatus according to the second embodiment when the sheet tray is pulled out;
FIG. 6B is an explanatory diagram showing a state of the sheet feeding device at the sheet setting position.

FIG. 13 is an explanatory diagram showing the operation of the sheet sending member at the sheet setting position of the sheet feeding device according to the second embodiment.

FIG. 14A is an explanatory view showing a movable mechanism at the time of inserting a sheet tray of the sheet feeding device according to the second embodiment;
FIG. 6B is an explanatory diagram showing a state of the sheet feeding device at a sheet feeding position.

[Explanation of symbols]

1 ... Sheet tray, 2 ... Sheet, 3 ... Tip guide, 3a
... end guide, 4 ... sheet delivery unit, 5 ... sheet delivery member, 6 ... spacing mechanism, 7 ... movable mechanism

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 15/00 514 G03G 15/00 514 F term (reference) 2H072 AB07 BA03 BA12 BA19 CA01 CA02 CB09 JA02 JA05 3F343 FA02 FC30 GA01 GB01 GC01 GD01 HA16 HC04 HC26 HC30 HE08 JA14 JD03 JD04 JD08 JD09 JD33 JD40 KB04 KB17 LA04 LA16 LB08 LC11 LC20

Claims (7)

[Claims] 1. A sheet tray that accommodates sheets and is provided so as to be drawn out between a sheet feeding position and a sheet setting position, and a sheet feeding unit that sequentially feeds the sheets accommodated in the sheet tray from above. In the sheet feeding apparatus, the sheet feeding unit is provided with at least a sheet feeding member which is provided on the side of the sheet tray and is arranged to face a sheet surface accommodated in the sheet tray. Among them, the sheet delivery member is movably provided between a feedable position in which the sheet is delivered by contacting the uppermost sheet and a retracted position separated from the feedable position, while the sheet is set at the sheet setting position of the sheet tray. The feeding member is arranged at the retracted position, and the sheet feeding unit is provided at the sheet feeding position of the sheet tray. There the sheet feeding apparatus is characterized by providing a movable mechanism disposed in a feed-enabled position. 2. The sheet feeding apparatus according to claim 1, wherein the movable mechanism moves the sheet feeding member in conjunction with the movement of the sheet tray. 3. The sheet feeding device according to claim 2, wherein the sheet sending member is movable at the sheet setting position of the sheet tray to a second retracted position further separated from the feedable position than the retracted position. A sheet feeding device. 4. The sheet feeding device according to claim 1, wherein the sheet feeding unit includes a sheet feeding member, and a mechanism for separating the sheets fed by the sheet feeding member one by one. A sheet feeding device, wherein the separating mechanism is arranged at a position outside an upper region of a sheet surface accommodated in a sheet tray. 5. The sheet feeding device according to claim 1, further comprising an inclined guide member provided at a position corresponding to a sheet feeding direction of the sheet tray and arranged to be inclined along the sheet feeding direction. A sheet feeding device characterized by being provided. 6. The sheet feeding device according to claim 5, further comprising a position regulating member that is provided separately from the inclined guide member and that regulates a sheet end face position by contacting an end face in the sheet feeding direction, and a sheet set of a sheet tray. A sheet feeding device characterized in that a position regulating member is disposed so as to project toward the sheet side with respect to the inclined guide member at a position, and an inclined guide member is disposed so as to project toward the sheet side relative to the position regulating member at a sheet feed position of the sheet tray. 7. An image forming apparatus comprising the sheet feeding device according to claim 1.