JP2002154675A - Sheet feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove a jammed sheet without reducing substantial space efficiency. SOLUTION: In this sheet feeder having a sheet tray 2 housing sheets S, and arranged so as to be freely taken in and out of this side of a feeder body 1, and a sheet feeding means 3 arranged on the inserting directional inmost side of the sheet tray 2, and sending out the sheets S in the sheet tray 2, an interlocking mechanism 4 is provided with moving the sheet feeding means 3 in the same direction as the sheet tray 2 by interlocking with the sheet tray 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus used in printers, copiers, facsimile machines, etc., and more particularly to a type in which sheets are fed from the back side in the insertion direction of a sheet tray which is provided so that it can be freely inserted and removed. The present invention relates to an improvement in a sheet feeding device.

[0002]

2. Description of the Related Art Conventionally known printers include, for example, a paper feed tray disposed so as to be able to be taken in and out from the front side of the apparatus, and a printer provided at the back of the paper feed tray in the insertion direction and accommodated in the paper feed tray. A sheet feeding unit that separates and feeds sheets one by one, an image forming unit that is provided above the sheet feeding tray and forms an image on the fed sheet, and is provided above the image forming unit; 2. Description of the Related Art There has been known a printer having a discharge tray from which a sheet after image formation is discharged from a rear side to a front side of the apparatus (see Japanese Patent Application Laid-Open No. 11-49881). In this type of printer, because of the above-described configuration, the paper transport path has a substantially U-shape, and the paper transport path is located at the back side when viewed from the insertion direction of the paper feed tray, that is, at the back side of the printer body. A road will be provided.

In such a printer, there is a problem that replacement of the paper feed tray is required according to the print size, and the operation becomes complicated accordingly. In view of the above, there is conventionally known a printer in which one or more additional paper feed units are provided below the main body of a printer so that paper according to a print size can be fed. Here, as the paper feeding unit, a paper feeding tray is provided so as to be able to be taken in and out of the paper feeding unit main body, and provided at the back side in the insertion direction of the paper feeding tray and housed in the paper feeding tray. A sheet feeding unit that separates and feeds sheets one by one is used. By doing so, the paper transport path in the paper feed unit can be located on the back side, and the paper sent from the paper feed unit can be smoothly transferred to the printer body.

[0004]

In such a paper feeding unit, paper jams (paper jams) may occur during paper transport. As a method of removing such paper jams, for example, a paper feeding unit may be used. An openable / closable door that also serves as a paper transport chute is provided at the back side of the paper unit main body, and the jammed paper is removed by opening this door (Japanese Patent Application Laid-Open No. 11-1999). 849
No. 81).

However, when such a method is adopted, a space in which a door can be opened and a space in which an operator can enter are secured on the back side of the paper feeding unit, that is, on the back side of the printer, in consideration of occurrence of paper jam. Therefore, there is a technical problem that a substantial occupied area is increased and space efficiency is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems, and it is possible to easily remove a jammed sheet without substantially reducing space efficiency. A feeding device is provided.

[0007]

That is, according to the present invention, as shown in FIG. 1 (a), a sheet tray 2 which accommodates sheets S and is disposed so as to be able to be taken in and out from the front side of the apparatus main body 1 is provided.
And a sheet feeding unit 3 provided on the back side in the insertion direction of the sheet tray 2 and feeding out the sheet S in the sheet tray 2. An interlocking mechanism 4 for moving the sheet feeding means 3 in the same direction as the tray 2 is provided.

In such technical means, the present invention relates not only to a sheet feeder used as an external unit of an image forming apparatus such as a printer, but also to a sheet feeder built in an image forming apparatus main body. The subject.

The sheet feeding means 3 has a function of feeding out the sheet S. For example, a feeding member for feeding out the sheet S on the sheet tray 1, a conveying member for conveying the fed out sheet S, and a conveying member And a guide member that forms a conveying path of the sheet S to be transported.

Further, the interlocking mechanism 4 interlocks with the sheet tray 2 and moves the sheet feeding means 3 in the same direction as the sheet tray 2.
If it moves, about the interlocking method,
A mode in which the sheet tray and the sheet feeding means are directly connected, a mode in which the sheet tray is indirectly connected via a sliding member, or the like may be appropriately selected. Here, from the viewpoint of facilitating sheet replenishment to the sheet tray 2, it is preferable to avoid a situation in which the sheet feeding means 3 covers the sheet tray 2 drawn out of the apparatus main body 1, as described above. In view of the above, the interlocking mechanism 4 is the same as that shown in FIG.
As shown in (a) to (c), it is preferable to move the sheet feeding means 3 so as to shift the relative positional relationship between the sheet tray 2 and the sheet feeding means 3 in the moving direction. Then, the interlocking mechanism 4 may move the sheet feeding means 3 together as shown in FIG. 1B when supplying sheets, that is, when pulling out only the sheet tray 2 from the apparatus main body 1, or As shown in FIG. 1D, the sheet feeding means 3 may be held at the initial position without moving.

The sheet feeding means 3 may be pulled out of the apparatus main body 1 every time the sheet tray 2 is pulled out. However, the length of the sheet feeding is increased. Since the mechanical parts such as the gears and rolls of the means 3 are exposed, there is a high risk that the sheet feeding means 3 may malfunction due to an erroneous operation of the user. From the viewpoint of preventing such a problem, as shown in FIG. 1B, the sheet tray 2 is pulled out of the apparatus main body 1 and the sheet feeding means 3 is moved to the apparatus main body 1 as shown in FIG. It is preferable to include a movement restricting means 5 for temporarily restricting the movement of the sheet tray 2 in the pull-out direction at a position where the sheet tray 2 is accommodated in the inside. When the sheet feeding means 3 is to be pulled out of the apparatus main body 1, the movement restricting means 5 may be released and pulled out.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the accompanying drawings. FIG. 2 shows a desktop laser printer (image forming unit 20) used in an embodiment of the image forming apparatus to which the present invention is applied.
In FIG. 1, the image forming unit 20 includes a paper feeding unit 20a for supplying paper, an image forming unit 20b for forming an image on the supplied paper, and a discharge tray 20c for discharging the paper after image formation. It has.

Here, the image forming section 20b forms an image using an electrophotographic method, and the photosensitive drum 2
1, a charging device 22 for uniformly charging the surface of the photosensitive drum 21, and a photosensitive drum 21 based on image data.
An image writing device 23 that irradiates the latent image with a laser beam Bm to form an electrostatic latent image, a developing device 24 that selectively transfers toner to the latent image to visualize the latent image, and a paper supply device 28 that is supplied along a paper transport path 28. Transfer device 25 for transferring a toner image on the surface of photoconductor drum 21 to a sheet of paper (not shown); fixing device 26 for fixing the toner image on the sheet by heating and pressing; And a cleaning device 27 for cleaning the toner remaining in the image forming apparatus. Reference numeral 29 denotes a registration roll provided on the upstream side of the paper transport path 28 and transporting the paper sent from a paper supply unit 20a described later to a toner image transfer position at a predetermined timing.

The paper supply section 20a includes two paper trays 31 and 32 disposed vertically and a first paper supply roll 3 for feeding paper from the upper or lower paper trays 31 and 32.
3 and the second paper feed roll 34, and each of these paper feed rolls 3
The paper trays 31 and 32 have holders 37 and 38 that are rotatably mounted on the paper trays 31 and 32 and that support the separators 35 and 36. The lower one of the paper trays 31 and 32 is detachable from the image forming unit 20 and can be pulled out to the near side (the right side in FIG. 2) of the image forming unit 20. it can. In the present embodiment, when the paper tray 32 that accommodates JIS A4 size vertically-fed paper is mounted, the entire paper tray 32 is accommodated in the image forming unit 20 (see FIG. 2).

On the other hand, the upper paper tray 31 is a manual feed tray, and paper of any size can be easily inserted from the front side of the image forming unit 20. Reference numeral 39 denotes a manual auxiliary tray provided on the front side of the paper tray 31 so as to be openable and closable. Reference numerals 40 and 41 guide the paper sent from the paper trays 31 and 32 toward the registration roll 29. It is a paper guide.

Further, in the image forming unit 20, the photosensitive drum 2 is provided for the purpose of improving maintenance.
A charging device 22, a developing device 24, a cleaning device 27, and the like in the vicinity thereof are integrally formed as a process cartridge 42.
2 is an upper cover 43 partly serving as the discharge tray 20c.
Is opened, it is possible to pull it up above the image forming unit 20.

In the image forming unit 20, the process cartridge 42 is configured to be detachable, so that the process cartridge 42 can be easily replaced, and a paper jam occurs in the image forming unit 20. In this case, the paper can be easily removed by removing the process cartridge 42. Further, when the process cartridge 42 is removed, the paper guides 40 and 41 are displaced because the paper guides 40 and 41 are arranged to be swingable about one roll axis of the registration roll 29. This makes it possible to easily remove the jam that has occurred at the site. Reference numeral 44 denotes the paper tray 32
And an external paper feeding unit 70 described later.
This is a paper transport path into which the paper sent from (see FIG. 5) is carried.

FIG. 3 shows the image forming unit 20 shown in FIG.
1 is a perspective view of Embodiment 1 of an image forming apparatus configured based on a (desktop laser printer). This image forming apparatus is a so-called multifunction peripheral having functions of a copier, a facsimile, a printer, and a scanner. In FIG. 1, the image forming apparatus according to the present embodiment includes an image forming unit 20 described above, an automatic document reading unit 50 disposed above the image forming unit 20, and an image forming unit disposed below the image forming unit 20. And a sheet feeding unit 60 as a sheet feeding device provided. Further, an operation panel 51 is disposed in front of the automatic document reading unit 50.

FIG. 4 is a side view of the image forming apparatus shown in FIG. Here, in the image forming apparatus according to the present embodiment, the depth of the sheet feeding unit 60 is set to the depth of the image forming unit 20 in order to store sheets larger than the sheets stored in the sheet tray 32 of the image forming unit 20. It is getting bigger. In the present embodiment, the image forming unit 20 is disposed so as to be biased toward the near side (the operation panel 51 side) of the image forming apparatus, so that the front surfaces of the image forming unit 20 and the sheet feeding unit 60 are substantially the same. Surface. A support wall 52 for supporting the automatic document reading unit 50 is provided on both side surfaces of the image forming unit 20, and a predetermined space is formed on a discharge tray 20c (see FIG. 2) of the image forming unit 20. It is supposed to be.

Next, the paper feeding unit 60 will be described with reference to FIG. In FIG. 5, the illustration of the automatic document reading unit 50 is omitted. In the present embodiment, the paper feed unit 60 is larger than the paper stored in the paper tray 32 of the image forming unit 20, for example, J
Two external paper supply units 70 capable of storing ISA3 size paper are provided. This external paper supply unit 70
Is a housing 71 and an external paper feed tray 72 that can be pulled out to the near side (right side in FIG. 5) of the image forming apparatus.
And a paper feed mechanism 7 provided at the upper part on the back side in the insertion direction of the external paper feed tray 72 and feeding out the inserted paper in the external paper feed tray 72 toward the image forming unit 20 side.
And 3.

FIG. 6A shows the external paper feeding unit 70.
Out of which the external paper feed tray 72 and the paper feed mechanism 73 are extracted. In FIG.
2 is a tray base 101 and the external paper feed tray 7
2 and a paper end guide movably provided from a substantially central portion of the external paper feed tray 72 toward the near side in the insertion direction. 103. The bottom plate 102 is swingable about a shaft 102a provided substantially at the center of the sheet feeding tray, and is urged upward in the figure by an urging member such as a spring (not shown). Have been. Reference numeral 104 denotes a lever for pulling out the external paper feed tray 72. On the other hand, the paper feeding mechanism 73 includes a paper feeding mechanism base 111 and an external paper feeding tray 7.
2, a half-moon-shaped feed roll 112 for feeding out paper (not shown), a pair of transport rolls 113 (113a, 113b) for transporting the fed paper, and an outer chute 114 for guiding the transported paper. And an inner chute 115. Further, corner separators 105 (FIG. 6) are provided at both ends of the external paper tray 72 on the back side in the insertion direction.
(See (b)).
Are fed out one by one. Reference numerals 116 and 117 are gears for transmitting a driving force to the feed roll 112 and the transport roll 113b.

As shown in FIG. 7, the outer chute 114 is rotatable about a shaft 114a provided at the lower end of the paper feed mechanism base 111. Is provided with the transport roll 113a. The outer chute 114 is urged toward the feed roll 112 by urging means such as a spring (not shown), and is usually positioned at a position indicated by a solid line in the drawing. On the other hand, the inner chute 115 is also rotatable about a shaft 115a provided below the paper feed mechanism base 111. And this inner chute 115
Normally, the outer chute 114 is positioned at a position shown by a solid line in FIG.

At a substantially central portion in the axial direction of the outer chute 114, a paper pincer lever 118 is provided. The paper scissor lever 118 has a curved surface substantially similar to that of the outer chute 114, and is urged toward the feed roll 112 by a torsion spring (not shown). When the paper feeding mechanism 73 is accommodated in the rear side of the housing 71, a projection (not shown) provided in the housing 71
When the back surface of the paper scissor lever 118 is pressed to form substantially the same surface as the outer chute 114 so as not to block the paper transport path, while the paper feed mechanism 73 is pulled out of the housing 71, The pressing by the projection (not shown) is released, and the sheet conveying path is closed by the urging force of a torsion spring (not shown).

As shown schematically in FIGS. 8A to 8C, the external paper supply unit 70 according to the present embodiment first supplies the paper supply mechanism 73 to the housing 71. The paper mechanism base 111 is connected to the outer rail 121 (121a, 121a).
b), and the tray base 101 of the external paper supply unit 72 with respect to the paper supply mechanism base 111 is supported by the inner rails 122 (122a, 122).
It is slidably supported via b). This allows
In the external paper feeding unit 70 according to the present embodiment, the external paper feeding tray 72 can be pulled out from the near side of the housing 71, and the paper feeding mechanism 73 can be pulled out of the housing 7.
1 can be pulled out from the near side.

A lock mechanism 130 for temporarily locking a drawer of the paper feed mechanism 73 is provided at a portion of the paper feed mechanism base 111 sandwiched between the outer rail 121a and the inner rail 122a. . As shown in FIG. 9A, the lock mechanism 130 includes a lever 131 that swings around a shaft 131a provided on a sheet feeding mechanism base 111, and a shaft 13 provided above the shaft 131a.
The first arm 132 includes an I-shaped first arm 132 connected to the first arm 1b, and an L-shaped second arm 133 connected to a shaft 132a provided at the other end of the first arm 132. The second arm 133 is swingable about a shaft 133a provided on the paper feed mechanism base 111, and has a free end formed with an inclined surface at one end and a vertical surface at the other end. Is formed. And
The lever 131 is provided with a spring 131 through a hole 131c.
d is attached, and the lever 131 is normally
Is to be energized. On the other hand, as shown in FIG. 8 and FIG.
A projection 71a with which the hook 133b is engaged is formed at the front side of the insertion direction 2 in FIG. This projection 71a
Has an inclined surface at one end corresponding to the hook 133b and an inclined surface at the other end, and are arranged such that the vertical surfaces and the inclined surfaces face each other.

Further, in this embodiment, as is apparent from FIG. 5, the position where the sheet is discharged from the external sheet supply unit 70 and the position of the sheet conveyance path 44 of the image forming unit 20 (the sheet is carried in). The paper feed unit 60 is provided with an intermediate transport unit 80 for aligning these paper transport paths. The intermediate conveyance unit 80 includes an external paper feeding unit 70.
A paper transport path 81 having a substantially S-shape for transporting the paper from the image forming unit 20 to the image forming unit 20 is formed.
To 84 are provided. Incidentally, in FIG.
Is a pedestal provided at the lowermost side of the paper feeding unit 60 to adjust the height of the image forming apparatus.

Next, an image forming process of the image forming apparatus according to the present embodiment will be described. When a copy button is pressed, a facsimile is received, or a print signal is received, a predetermined image forming process is executed. More specifically, for example, when copying is performed, an original is read by the automatic original reading unit 50, the read signal is converted into a digital image signal by an image signal processing device (not shown), and temporarily stored in a memory (not shown). The toner image is accumulated and a toner image is formed based on the digital image signal.

That is, in accordance with the digital image signal input from the image signal processing device, the image writing device 23 writes an electrostatic latent image on the photosensitive drum 21 uniformly charged by the charging device 22. . Then, the formed electrostatic latent image is developed by the developing device 24 to form a toner image.
On the other hand, the sheet is transported at a predetermined timing to a transfer position where the photosensitive drum 21 and the transfer device 25 face each other. Then, at the transfer position, the photosensitive drum 21 and the transfer device 2
5, the toner image carried on the photosensitive drum 21 is transferred to the sheet by the action of the transfer electric field formed between the photosensitive drum 21 and the photosensitive drum 21. The sheet on which the toner image has been transferred is conveyed to the fixing device 26, where the toner image is fixed.
Is discharged on top. On the other hand, the toner remaining on the photosensitive drum 21 after the transfer is cleaned by the cleaning device 27.

Here, a paper supply method of the external paper supply unit 70 according to the present embodiment will be described. When replenishing paper to the external paper supply unit 70, the user first pulls out the lever 104 of the external paper supply tray 72 to the front side of the apparatus as shown in FIG. At this time, in the external paper feed unit 70, as shown in FIGS. 8A and 8B, the external paper feed tray 72 is first pulled out while sliding on the inner rail 122 with the pulling out of the lever 104. Next, when the inner rail 122 is fully extended, the paper feed mechanism base 111 (and the paper feed mechanism 73) is pulled out while sliding on the outer rail 121 while being pulled by the external paper feed tray 72. Then, the paper feed mechanism base 111
When the hook 133b of the lock mechanism 130 provided on the housing abuts on the projection 71a of the housing 71, the pulling out of the external paper tray 72 and the paper feed mechanism 73 is stopped.

At this time, the positional relationship between the pulled out external paper feed tray 72 and the paper feed mechanism 73 is as shown in FIG. 6B and FIG. Feed roll 112 located above paper tray 72
(See FIG. 6 (a).) At the time of pulling out, it is in a state of being disposed relatively deeper than the external paper feed tray 72. Therefore, as shown in FIGS. 8B and 10, there is nothing to block the external paper feed tray 72 that has come out of the housing 71, and the insertion of new paper becomes easy. In addition, when only paper supply is performed, the entire paper feed mechanism 73 is not pulled out of the housing 71 by the lock mechanism 130, and accordingly, the length of the paper feed mechanism 73 is reduced accordingly.

Next, a method for removing a paper jam generated in the external paper supply unit 70 according to the present embodiment will be described. When removing jammed paper in the external paper supply unit 70, the user first pulls out the lever 104 of the external paper supply tray 72 toward the apparatus as shown in FIG. At this time, in the external paper supply unit 70, FIG.
(A) and (b), when the lever 104 is pulled out, first, the external paper feed tray 72 is
2 slides out and then this inner rail 1
When the sheet 22 is fully extended, the sheet feeding mechanism base 111 (and the sheet feeding mechanism 73) is pulled out while sliding on the outer rail 121 while being pulled by the external sheet feeding tray 72.
At this time, as the paper feed mechanism base 111 is pulled out,
Pressing of the paper scissor lever 118 shown in FIG. 7 is released, and the paper scissor lever 118 is tilted down toward the paper transport path, and the jammed paper is forcibly pinched in the paper transport path. Then, when the hook 133b of the lock mechanism 130 provided on the paper feed mechanism base 111 hits the projection 71a of the housing 71, the pulling out of the external paper feed tray 72 and the paper feed mechanism 73 is temporarily stopped.

After that, the user tilts the lever 131 that has come out of the housing 71 in the direction toward the front of the apparatus in FIGS. 10 and 11 (to the right in FIG. 9A). Then, as shown in FIG. 9B, the engagement between the hook 133b and the projection 71a is released, and when the user further pulls out the lever 104 in this state, the hook 133b is pulled by the external paper supply tray 72. Then, the paper feed mechanism base 111 (and the paper feed mechanism 73) is further pulled out while sliding on the outer rail 121. Then, immediately after the entire sheet feeding mechanism 73 comes out of the housing 71, the outer rail 121 extends completely, and the pulling out of the external sheet feeding tray 72 and the sheet feeding mechanism 73 is finally stopped.

Then, the user pushes and rotates the outer chute 114 shown in FIG. 7 to rotate the paper chute (a paper conveyance path formed between the outer chute 114 and the inner chute 115 and a conveyance path between the inner chute 115 and the inner chute 115). Roll 113
b) and release the two paper transport paths formed between
The jammed sheet is dragged out to complete the jam processing.

In the present embodiment, the feeding mechanism 73 is
1 can be pulled out to the front side (the front side of the image forming apparatus) so that even when a paper jam occurs in a paper conveyance path provided on the back side of the external paper supply tray 72, the user side ( The jammed sheet can be removed from the front side of the image forming apparatus).

[0035]

As described above, according to the present invention,
Since the sheet feeding means provided on the back side of the sheet tray is pulled out to the front side of the apparatus in conjunction with the sheet tray, both sheet supply and sheet jam processing can be performed from the front side of the apparatus, Therefore, the jammed sheet can be easily removed without substantially lowering the space efficiency.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating an outline of an image forming apparatus according to the present invention.

FIG. 2 is an explanatory diagram illustrating an outline of a desktop laser printer (image forming unit) used in the image forming apparatus according to the embodiment;

FIG. 3 is a perspective view of the image forming apparatus according to the embodiment.

FIG. 4 is a side view of the image forming apparatus according to the embodiment.

FIG. 5 is a sectional view of an image forming unit and a sheet feeding unit according to the embodiment.

FIGS. 6A and 6B are cross-sectional views of an external paper feed unit.

FIG. 7 is an explanatory diagram of a sheet feeding mechanism.

FIGS. 8A to 8C are schematic diagrams showing the insertion and removal of an external paper feed tray and a paper feed mechanism in an external paper feed unit.

FIGS. 9A and 9B are explanatory views of a lock mechanism of a paper feeding mechanism.

FIG. 10 is an explanatory diagram of a paper feeding method in an external paper feeding unit.

FIG. 11 is an explanatory diagram of a jam clearing method in an external paper feeding unit.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device main body, 2 ... Sheet tray, 3 ... Sheet feeding means, 4 ... Interlocking mechanism, 5 ... Movement restriction means, S ... Sheet

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshiaki Misu 3-7-1, Fuuchi, Iwatsuki-shi, Saitama Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Masakuni Nishimura 3-7-1, Fuuchi, Iwatsuki-shi, Saitama Fuji X-Flux Co., Ltd. F-term (reference) 3F343 FA02 FB02 FB03 FB04 FC30 GA01 GB01 GC01 GD01 HA16 HA22 HA29 HA31 HB01 HB03 HC04 HC25 HC26 HC30 KB03 KB04 KB05 KB06 KB13 KB14 LA04 LA13

Claims (3)

[Claims] 1. A sheet tray which accommodates sheets and is disposed so as to be able to be taken in and out from the front side of the apparatus main body, and a sheet feeding means which is provided at the back side in the insertion direction of the sheet trays and feeds out the sheets in the sheet trays. A sheet feeding device comprising: an interlocking mechanism that moves the sheet feeding unit in the same direction as the sheet tray in conjunction with the sheet tray. 2. The sheet feeding device according to claim 1, wherein the interlocking mechanism moves the sheet feeding unit so as to shift a relative positional relationship between the sheet tray and the sheet feeding unit in a moving direction. A sheet feeding device. 3. The sheet feeding device according to claim 1, wherein the sheet tray is pulled out of the apparatus main body, and the sheet tray is moved to a position where the sheet feeding means is accommodated in the apparatus main body. A sheet feeding device comprising a movement restricting means for temporarily restricting movement in a pull-out direction.