Automatic document feeder

A compact automatic document feeder having a document storage portion including a document tray for placing thereon given original documents to be fed into an image processing device such as a copying machine, and a document receiving device disposed on the document tray. The document receiving device comprises document holding members movable widthwise for holding the document to be fed into the image processing device, and document supporting members for receiving the document discharged from the image processing device is adapted to effectively divide the document stacked on the document tray and the discharged document independently, so as to prevent the document being discharged from colliding with the document left on the document tray.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an automatic document feeder for automatically 
feeding given original documents one by one to the image reading station 
of an image processing device such as a copying machine and printer, and 
more particularly, to a compact and simple document feeder having a common 
document tray for placing thereon one or more original documents to be fed 
into the image processing device and receiving the documents sent out from 
the image processing device. 
2. Description of the Prior Art 
For coping with a need for downsizing image processing devices such as a 
copying machine, facsimile, image scanner, and printer, the latest 
automatic document feeders mounted on the image processing devices tend to 
be made compact without degrading the performance in handling and 
transporting the given original document. The copying machine typical of 
the image processing device generally has a transparent platen on which an 
image reading station is defined and one given original document is placed 
for being optically scanned to read an image on the document. On the 
platen, there is mounted the document feeder for automatically feeding and 
sending out the given original document to and from the image reading 
station defined on the platen. 
The automatic document feeder usually comprises a document feeding tray for 
placing thereon the original documents to be fed hereafter one by one to 
the image reading station on the platen, and a document discharging tray 
for receiving the original documents sent out from the image reading 
station upon completion of image processing. For directly transporting the 
document to and from the image reading station, a document transporting 
unit is built into the document feeder and overlaid on the platen. 
It has been so far attempted to place the document feeding tray and 
document discharging tray one upon another in order to reduce the area 
occupied by the document feeder. One illustrative instance of the document 
feeders of this kind is disclosed in U.S. Pat. No. 4,023,791 (corresp. to 
Japanese Pat. Publication No. SHO 60-657(B2). 
In the document feeder proposed by said U.S. Patent, the document feeding 
tray is independently placed on and displaced horizontally from the 
document discharging tray to facilitate the removal of the discharged 
original documents from the document discharging tray, resulting in a 
large overall size of the document feeder. Furthermore, the proposed 
document feeder is likely to entail a disadvantage such that, when the 
document to be fed has the habit such as curvature, the leading end of the 
document sent out from the image processing device to the document 
discharging tray by the document transporting unit after image processing 
is possibly caught by the bottom of the document feeding tray. 
A document feeder proposed by Japanese Patent Application Public Disclosure 
No. HEI 3-120125(A) has a document tray for placing a stack of original 
documents thereon. In this proposed feeder, the documents stacked on the 
document tray are drawn one by one and fed to an image reading station and 
sent back from the image reading station onto the top of the stack of 
documents left on the document tray in a U-turn. The documents sent back 
from the image reading station and the stack of documents still left on 
the document tray are divided by a pair of document receiving members. The 
document being discharged from the image processing station moves in the 
opposite direction to the direction in which the document left on the 
document tray is sent into the image reading station, while coming in 
sliding contact with the document stacked on the document tray from the 
leading end toward the tail end of the document. When discharging the 
document from the image reading station onto the unfed documents stacked 
on the document tray, there is a possibility that the leading end of the 
discharged document collides with the leading end of the the stack of 
documents left on the document tray, thus causing the discharged document 
to be obstructed by the stack of documents left on the document tray. 
A document feeder of different type has been proposed, which has a common 
document tray serving as a document feeding tray for feeding documents to 
be fed to the image reading station in a copying machine and a document 
discharging tray for receiving the documents sent out from the image 
reading station. For instance, a recycling automatic document feeder 
(generally called "recycle-ADF") for circulating several times a plurality 
of original documents through a transporting passage including the image 
reading station to obtain a plurality of sets of copies is disclosed in 
Japanese Patent Application Public Disclosures Nos. SHO 55-98762(A) and 
SHO. 59-114249(A). 
The document tray in the conventional recycle-ADF is formed by merely 
combining the document feeding tray and document discharging tray, so that 
the documents sent out from the image reading station of the copying 
machine each time the image processing is completed are put on the top of 
the unfed documents stacked on the document tray. To count the number of 
the circulation of the documents being subjected to image processing, a 
cycle counting lever is interposed between the documents to be fed to the 
image reading station and the discharged documents sent out from the image 
reading station. 
In the conventional ADF described above, since the documents still left on 
the tray to be read and the discharged documents sent out from the image 
reading station are divided only by the simple counting lever, but not 
independently separated from each other, the discharged document possibly 
collides with the unfed documents stacked on the document tray, thus 
developing feeding trouble and causing the discharged documents to be out 
of order. This disadvantage becomes particularly conspicuous when the 
original documents different in size are dealt with. 
If a partition member is used to prevent the unfed documents stacked on the 
document tray to be read from interfering with the advancing of the 
document discharged from the image reading station, the handling work of 
getting the documents in and out relative to the document tray becomes 
onerous. 
OBJECT OF THE INVENTION 
This invention is made to eliminate the drawbacks suffered by the 
conventional document feeders as described above and has an object to 
provide a convenient automatic document feeder having a common document 
tray capable of infallibly feeding unfed original documents to be dealt 
with one by one to the image reading station of an image processing device 
and receiving the documents sent out from the image reading station 
without colliding with the aforesaid unfed document to be dealt with upon 
completion of image processing. 
Another object of this invention is to provide an automatic document feeder 
which is made compact and simple by integrating a document feeding tray 
for placing and feeding one or more original documents one by one to the 
image reading station with a document discharging tray for receiving the 
documents discharged from the image reading station, with a structure 
capable of definitely dividing the documents to be dealt with and the 
discharged documents, so as to prevent the leading end of the discharged 
documents from colliding with the unfed document left on the document 
tray. 
Still another object of this invention is to provide an automatic document 
feeder capable of easily placing and removing original documents on and 
from a document storage portion and effectively dealing with various 
documents even different in size. 
Yet another object of this invention is to provide an automatic document 
feeder which can be applied to a variety of image processing devices such 
as a copying machine, printer, facsimile and image scanner and all sorts 
of devices to which a sheet material is required to be automatically fed, 
and capable of manually placing and removing an original document onto and 
from the image processing devices at need. 
SUMMARY OF THE INVENTION 
To attain the objects described above according to this invention, there is 
provided an automatic document feeder comprising a document tray for 
placing thereon one or more original documents to be fed, a document 
transporting means having a document feeding part for transferring the 
documents one by one to an image reading station of an image processing 
device and a document discharging part for sending out the document from 
the image reading station, and document receiving means having a pair of 
document holding members standing upright on the document tray and a pair 
of document supporting members attached to the respective document holding 
members for receiving the document sent out from the image reading 
station. 
At least one of the document holding members is movable so as to true up 
the side edges of the documents stacked on the document tray. 
Close to the discharge port formed in the document discharging part of the 
document transporting means, a curing member is formed on the document 
tray for allowing the document discharged from the discharge port to be 
maintained flat so as not to cause the leading end of the discharged 
document to collide with the tail end of the stack of documents on the 
document tray. 
The document feeder is mounted on an image processing device such as a 
copying machine in such a state that the image reading station defined on 
the image processing device is overlaid with the document transporting 
means. 
The document supporting members extending horizontally from the upper ends 
of the document holding means have concave notches defining a wide opening 
through which the documents can easily be placed on the document tray. 
The document tray is provided with at least one pivoted guide piece which 
elastically protrudes upward in a normal state and is retractable under 
the upper surface of the document tray when one or more documents are put 
thereon. In the state that the pivoted guide piece protrudes upward, when 
the given document lacks firmness and is bent downward when being 
discharged from the discharge port, the leading end of the document being 
discharged collides with the guide piece, thus leading the document 
discharged from the image reading station is no longer hindered in its 
forward movement by the tail end of the unfed document stacked on the 
document tray. 
Other and further objects of this invention will become obvious upon an 
understanding of the illustrative embodiments about to be described or 
will be indicated in the appended claims, and various advantages not 
referred to herein will occur to one skilled in the art upon employment of 
the invention in practice.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
This invention will become more fully understood from the detailed 
description given hereinbelow and the accompanying drawings which are 
given by way illustration only, and thus are not limitative of the present 
invention. 
The automatic document feeder according to this invention is applicable to 
image processing devices of all types of requiring to automatically feed 
one or more given original documents to be dealt with, such as a copying 
machine, printer, facsimile and image scanner. In The illustrative 
embodiments described hereinafter, the automatic document feeder of this 
invention is applied to the copying machine by way of example. 
The automatic document feeder 1 of this invention is mounted on the copying 
machine M as illustrated in FIGS. 1 and 3. The image processing device 
(copying machine M) of this kind generally comprises an image reading 
mechanism having a transparent platen P on which an image reading station 
RS is defined for optically scanning the image surface of the given 
original document placed thereon. 
The document feeder 1 is pivotally fixed at one side edge thereof on the 
copying machine M by hinge means (not shown), so as to be lifted up 
rotatably about the hinge means to open the image reading station RS. 
The document feeder 1 principally includes a housing 2 having a document 
storage portion 10 formed in a concave shape, and a document transporting 
means 20 disposed within the housing 2. 
The document storage portion 10 in this embodiment is defined by at least 
one side wall 2a, a front wall 2b and a rear wall 2c of the housing 2. The 
front wall 2b has a document intake port 10a, and the rear wall 2c has a 
document discharge port 10b. The bottom of the document storage portion 10 
is substantially on a level with the lower edge of the document intake 
port 10a to form a document tray 11 on which one or more original 
documents d1 to be subjected to image processing are placed. 
On the document tray 11 is disposed a document receiving means 12 
comprising a pair of document holding members 13 standing upright, and a 
pair of document supporting members 15 extending horizontally from the 
respective upper ends of the document holding members 13. The document 
holding members 13 have document keeping plates 13a extending in the 
direction facing to each other. 
In this embodiment, the document receiving means 12 consisting of the 
document holding members 13 and document supporting members 15 is slidably 
movable widthwise along guide slits 11a formed in the document tray 11 and 
extending in parallel in the width direction of the document d1 placed on 
the document tray 11, so as to vary the distance between the holding 
members 13 in accordance with the width of the document d1 placed between 
the holding members 13. Thus, the stack of documents d1 to be fed to the 
image reading station RS can be securely held with the side edges being 
turned up by the document holding members 13. 
For moving the paired document receiving means 12 in opposite directions to 
vary the distance therebetween, there may be used a parallel moving 
mechanism 14 comprising racks 14a attached to the respective document 
keeping plates 13a through the slits 11a and a pinion 14b located between 
the racks 14a, as illustrated in FIG. 4 as one example. With this parallel 
moving mechanism 14, by moving one of the paired document holding members 
13 in one direction, the other holding member 13 is moved in the opposite 
direction at a time. Thus, the distance between the document holding 
members 13 can vary without changing the center between the holding 
members 13. 
Though both the document holding members 13 are moved in opposite 
directions at a time in this embodiment, only one of the document holding 
members 13 may be made movable. In this case, for example, the side wall 
2a defining the document storage portion 10 in conjunction with the front 
and rear walls 2b and 2c may be used as the other stationary document 
holding member, and it is sufficient to form only one guide slit 11a. 
The parallel moving mechanism for transmitting the movement of one of the 
document holding members 13 to the other document holding member 13 can be 
otherwise composed of towing belts or an endless towing belt passed around 
wheels secured rotatably on the document tray and connected to the 
document holding members 13. 
To facilitate the placing of the given documents d1 to be dealt with onto 
the document tray 11, the opposed inside edge portions of the document 
supporting members 15 are partially cut to form concave notches 15a and 
15b for defining wide openings through which the documents can be passed 
and placed on the document tray 11 with ease. By forming the concave 
notches 15a and 15b in the document supporting members 15, the paired 
document holding members 13 need not open to the extent equal to the width 
of the given document, because the document can be passed through the 
opening formed by the opposed concave notches 15a or 15b. Therefore, it is 
desirable to determine the depth of each concave notch according to the 
width of the document of high frequency in use. 
Each of the document supporting members 15 slantingly extends substantially 
from the upper edge of the document intake port 10a formed in the front 
wall 2b toward the lower edge of the document discharge port 10b formed in 
the rear wall 2c. The document sent out via the discharge port 10b moves 
forward with its side portions coming into face contact with the upper 
surface of the document supporting members 15 as indicated by d2 in FIG. 
2, and finally rests on the document supporting members 15 above the 
document tray 11 as indicated by d3. 
There is a case that the document d2 discharged from and through the 
document discharge port 10b is bent downward in the width direction, 
causing the middle portion thereof to be near the document tray 11, when 
the given document is made of a relatively wide and thin sheet of paper 
and lacks firmness. In such a case, there is a possibility that the 
leading end of the discharged document d2 collides with the rear end of 
the stack of documents d1 still left on the document tray 11, thus causing 
the trouble of discharging the document. 
To remedy the drawback noted above, the document tray 11 is provided with 
guide pieces 16a and 16b to discharge the documents successfully. As 
illustrated in FIG. 5, each of the guide pieces 16a and 16b is formed of a 
triangular plate and pivoted at its one corner on the document tray 11, so 
that they elastically protrude upward in a normal state through a hole 17 
(i.e. guide piece 16b in FIG. 5), and are retracted under the upper 
surface of the document tray 11 when one or more documents are put thereon 
(i.e. guide piece 16a in FIG. 5). One side of each of the triangular guide 
pieces 16a and 16b, which faces the document discharge port 10b, inclines 
to form a sliding slope 16' so as to lead upwardly the document d2 
discharged from the document discharge port 10b. 
The guide pieces 16a and 16b pivoted on the document tray 11 cannot 
withstand the vertical force fv brought about by the weight of the 
documents, thus withdrawing downward under the document tray 11, but can 
withstand the horizontal force fh brought about by the document moving 
forward. Accordingly, in the state that the pivoted guide piece protrudes 
upward, when the document being discharged from the discharge port 10b 
lacks firmness and is bent downward, the leading end of the document 
collides with the sliding slope 16' of the guide piece, thus leading the 
document upwardly. As a result, the document is no longer hindered in its 
forward movement by the tail end of the document stacked on the document 
tray 11. 
Though this embodiment is illustrated as using two guide pieces 16a and 
16b, the number of such guide pieces is not specifically limited. Only a 
single guide piece or three or more guide pieces may be used selectively. 
When two guide pieces are used as in this embodiment, they may be 
preferably arranged in accordance with the length of the document of high 
frequency in use as illustrated. For example, the first guide piece 16a is 
located at distance A4W from the document intake port 10a which 
corresponds to the width of a sheet of A4 size (297 mm.times.210 mm), and 
the second guide piece 16b is located at distance A4L from the document 
intake port 10a which corresponds to the length of the A4 size sheet. 
Though each guide piece is made of a triangular plastic plate in this 
embodiment, the shape and material of the guide piece are by no means 
limitative. For instance, the guide piece may be formed by bending a 
metallic wire in an L-shape. 
Close to the document discharge port 10b formed at the rear end of the 
document tray 11, a curing member 18 is disposed on the document tray 11. 
This curing member 18 serves to allow the document d2 discharged from the 
discharge port 10b to be maintained flat, so as not to cause the leading 
end of the discharged document d2 to collide with the tail end of the 
stack of documents d1 left on the document tray 11. Though the curing 
member 18 in this embodiment has a triangular section having an inclined 
upper surface, this should be not understood as limitative. The upper 
surface of the curing member 18 may be of course made flat horizontally, 
or otherwise, the curing member may be formed by upwardly bending the 
surface of the document tray 11 in a step shape. 
The document transporting means 20 comprises at least one endless belt 21 
supported between driving pulleys 22a and 22b and coming into face contact 
with the platen P of the copying machine M to define the image reading 
station RS, a document feed part 30 for sending the documents d1 stacked 
on the document tray 11 one by one from the document intake port 10a to 
the image reading station RS defined between the endless belt 21 and the 
platen P through a feed passage R1, and a document discharging part 40 for 
transporting the document from the image reading station RS to the 
document discharge port 10b through a discharge passage R2. 
The feed passage R1 is curved in a substantially U-shape, so that the 
document is turned upside down when being fed from the document tray 11 to 
the image reading station RS. Also, the discharge passage R2 is formed in 
a substantially U-shape, so that the document is turned upside down when 
being sent out from the image reading station RS onto the document 
receiving means 12 through the discharge port 10b. 
When giving copying instructions to the copying machine M, the document 
feeder 1 is operated to draw out one of the original documents d1 stacked 
on the document tray 11 into the feed passage R1 through the document 
intake port 10a and further send the document into the image reading 
station RS. After copying, the document is transported from the image 
reading station RS to the discharge port 10b through the discharge passage 
R2 and further sent out onto the document receiving means 12. 
At the exit of the image reading station RS defined between the endless 
belt 21 and the platen P, a document stopper 23 is disposed. When the 
given document d1 is sent into the image reading station RS through the 
feed passage R1, the stopper 23 rises to impede the forward movement of 
the document, so that the leading end of the document collides with the 
stopper 23 to bring the document to a stop at the prescribed position in 
the image reading station RS. When the copying is completed, the stopper 
23 sinks to allow the document to pass over the stopper 23. 
In FIG. 3, reference numeral 24 denotes pressure rollers for resiliently 
pressing the endless belt 21 against the platen P. 
The document feeding part 30 includes at least one pickup roller 31 for 
sending out the lowermost document of the documents d1 stacked on the 
document tray 11 to the feed passage R1, a separation means 32 composed of 
at least one set of separation roller 32a and separation pad 32b coming in 
frictional contact with the separation roller 32a for allowing only one 
document to pass therethrough, and at least one set of register rollers 
33a and 33b for correcting the inclination of the document sent out from 
the document tray. The pickup roller 51, separation means 32, and register 
rollers 33a, 33b are arranged along the feed passage R1 as shown in FIG. 
6. 
The register rollers 33a and 33b do not rotate until the document sent from 
the document tray 11 through the separation means 32 collides with the nip 
portion at which the register rollers 33a and 33b come in press contact 
with each other. Immediately after the document collides with the nip 
portion between the register rollers, the register rollers start to rotate 
to allow the document to pass therethrough. 
Even if the document is forwarded slantwise, the leading end of the 
document entirely comes in touch with the nip portion between the register 
rollers, when colliding with the nip portion. As a result, the document 
moves straightforwardly through the register rollers in the direction 
parallel to the document transporting direction. 
Opposite to the pickup roller 31, an empty sensor 35 is placed for 
detecting the presence of the document d1 on the document tray. 
Between the pickup roller 31 and the separation means 32, there is disposed 
a stopper gate 36 which is moved downward to permit the document d1 on the 
document tray 11 to pass therethrough upon receiving an operation signal 
from the copying machine M. 
In FIG. 6, reference numeral 37 denotes a weight lever for urging the 
documents d1 against the document tray numeral 38 denotes an idle roller, 
and 39a and 39b denote a light emitting element and a photodetector for 
detecting the document passing therebetween. 
The document discharging part 40 includes a turn-over roller 41 of a large 
diameter, and guide rollers 43 as illustrated in FIG. 7. Opposite to the 
turn-over roller 41, a guide plate 42a is arranged to define the aforesaid 
discharge passage R2, and another guide plate 42b is arranged to define a 
turn-over passage R3. Reference numeral 44 denotes a discharge roller. A 
switching lever 45 is disposed at the junction of the discharge passage R2 
and the turn-over passage R3. In the normal state, the switching lever 45 
permits the discharge passage R2 to communicate with the discharge port 
10b. When effecting duplex copying, the switching lever is operated to 
close the path to the discharge port 10b and connect discharge passage R2 
and turn-over passage R3. Thus, in the case of duplex copying, after 
copying one side of the document, the document printed on its both sides 
is first sent back, being turned upside down, to the image reading station 
RS through the discharge passage R2 and turn-over passage R3. Then, after 
copying the reverse of the document, the document is discharged from the 
image reading station RS through the discharge passage R2 and the 
discharge port 10b. 
The document transporting means 20 including the endless belt 21, document 
feeding part 30 and document discharging part 40 is not specifically 
limited to the illustrated structure, but it may be chosen from the 
conventional document transporting means of various types for this 
invention. 
The operation and function of the document feeder noted above according to 
this invention will be described hereinafter. 
In placing one or more given original documents d1 be dealt with on the 
document tray 11, the document receiving means 13 are first opened to 
permit the documents d1 to pass into the document tray 11. The documents 
d1 may be passed through the opening formed by the opposed concave notches 
15a or 15b formed in document supporting members 15 as occasion demands. 
Then, the documents d1 are inserted into the document intake port 10a 
until the leading end of the sheaf of documents touches the stopper gate 
36 in the document feeding part 30. The documents d1 thus placed on the 
document tray 11 are securely held by closing the document holding means 
13 to true up the side edge of the stack of documents d1 as shown in FIG. 
1. 
When the tail end portion of the stack of documents d1 is placed on the 
guide piece 15a or 15b, the guide piece is retracted downward in the 
document tray 11. 
At the time of given copying instructions to the copying machine M, the 
document feeding part 30 starts to operate so that one of the documents d1 
is drawn out from the document tray 11 and transported to the image 
reading station RS defined on the platen P through the feed passage R1. 
Upon completion of copying, the document transporting means 20 and 
document discharging part 40 are driven to send out the document from the 
image reading station RS through the discharge passage R2 and discharge 
the document d2 onto the document receiving means 12 through the discharge 
port 10b as shown in FIG. 2. 
When the first document of the stack of documents d1 on the document tray 
11 is sent to and discharged from the image reading station RS, the 
central portion of the document being discharged from the discharge port 
10b weighed down to a certain degree while being held at both sides by the 
document supporting members 15. In a case of dealing with the document 
lacking firmness, the central portion of the document which is weighed 
down possibly comes in touch with the surface of the document tray 11. 
Even if the document moves forward touching the document tray, the 
document is advantageously led upward specifically by the guide piece 16b 
as shown in FIG. 5. 
Even when the document of a rigid sheet is used and moves forward over the 
guide piece 16b, it may be guided by the guide piece 16a. Thus, in any 
event, the document d2 discharged from the discharge port 10b can be 
properly placed in position on the document receiving means 12 without 
thrusting into neither colliding with the stack of documents d1 left on 
the document tray 11. The tail end portion of the discharged document is 
not supported by the document receiving means 12, but placed on the curing 
means 18 and maintained flat horizontally, so as not to cause obstruction 
to passage of the subsequent document discharged from the discharge port 
10b. 
The remaining documents d1 stacked on the document tray 11 are successively 
transported and overlaid on the first document resting on the document 
receiving means 12 one after another. 
To prevent the discharged document advancing forward along the upper 
surface of the document receiving means 12 from intruding into the 
document intake port 10a through a gap between the front wall 2b of the 
housing 2 and the front end of the document receiving means 12, it is 
desirable to rather increase the height of the front wall 2b of the 
housing 2. 
As described above, according to the automatic document feeder of this 
invention, the space on the document tray can be commonly applied for 
stacking the documents to be dealt with and receiving the documents 
discharged from the image processing device, as a result which the 
document feeder can be made compact with improving its space factor and 
operation efficiency. Besides, the given original documents can be 
effectively transported without interfering between the documents stacked 
on the document tray and the document coming back from the image reading 
station. 
The concave notches 15a and 15b formed in the document supporting members 
15 on which the discharged document is placed are not absolutely necessary 
to this invention. As shown in FIG. 8, the document supporting members 55 
may be formed in a shape tapered off toward the discharge port 10b. In the 
embodiment shown in FIG. 8, the reference numerals which have equivalents 
in the diagrams of the foregoing embodiment mentioned above denote 
identical or equal component parts. The description of these component 
parts is omitted below to avoid repetition. 
The embodiment of FIG. 8 includes a guide member 56 having a free end 
inclined upward toward the discharge port 10b so as to facilitate 
insertion of the documents into the intake port 10a. The guide member 56 
is made of a steel wire or the like and hinged on the housing 2 so that it 
can be turned out upward. 
The guide member 56 has functions of not only facilitating the insertion of 
the documents into the intake port 10a, but also preventing the original 
document being discharged from the discharge port 10b from entering into 
between the front wall 2b and the front end of the document receiving 
means 12. 
In the third embodiment shown in FIG. 9, document supporting members 65 of 
paired document receiving means are each formed of a substantially 
L-shaped plate and partially overlap with each other on the side of the 
intake port 10a. The front end portions of the document supporting members 
65 near the intake port 10a are made higher than the upper surface of the 
housing 2, so that the document being discharged from the discharge port 
10b is prevented from intruding into the intake port 10a through between 
the front wall and the front end of the document supporting members 65. 
The identical or similar components of this embodiment are denoted by the 
same numerical symbols. 
Also in the fourth embodiment shown in FIG. 10, for the purpose of 
preventing the document discharged from the discharge port 10b from 
intruding into the intake port 10athrough between the front wall 2b and 
the front end of the document receiving means, a rising portion 72 
extending widthwise is formed on the document tray 71. The opposite 
portion of each of document supporting members 75 to the rising portion 71 
is curved upward to form a convex portion 76. The document which is being 
discharged from the discharge port 10b and moves forward along the upper 
surfaces of the document supporting members 75 collides with the convex 
portions 76, so that it does in no way intrude into the document intake 
port through between the front wall 2b and the front end of the document 
supporting members 75. 
A modified embodiment shown in FIG. 11 has a first document receiving means 
82a composed of a document holding member and document supporting member 
85, and a second document receiving means 82b composed of a document 
holding member 83. This embodiment enjoys an advantage in that the 
documents to be dealt with can be placed on the document tray 11 with 
ease. 
Also in the embodiment shown in FIG. 12, a document supporting member 95 is 
disposed only on one document holding member 93a to form a first document 
receiving means 92a. A second document receiving means 92b is composed of 
only a document holding member 93a. The document supporting member 95 is 
hinged on the document holding member 93 so as to be opened upwardly when 
placing the documents on the document tray 11. 
This embodiment has a curing member 98 formed by rising the rear end 
portion of the document tray 11 in a step shape. This curing member 98 
serves to allow the document discharged from the discharge port 10b to be 
maintained flat horizontally, so as not to cause the leading end of the 
discharged document to collide with the tail end of the documents stacked 
on the document tray 11. 
As is apparent from the above, the document supporting member may be 
provided on at least one of the document receiving means, but not 
necessarily disposed on both the document receiving means. Furthermore, 
the document supporting member is not limited in shape and may have any 
other desired shape capable of permitting the given original documents to 
be easily placed on the document tray and reliably receiving the document 
sent out from the image reading station defined on the image processing 
device. 
EFFECT OF THE INVENTION 
As described in detail above, the present invention provides an automatic 
document feeder capable of effectively feeding given original documents 
stacked on a document tray in a document storage portion one by one to the 
image reading station of an image processing device and discharging the 
document from the image reading station onto a document receiving means 
disposed above the document tray, and further placing the discharged 
documents in the document storage portion independently of the unfed 
documents stacked on the document tray. Since the document feeder of this 
invention has a structure in which the document sent out from the image 
reading station is sent out to the document storage portion including the 
document tray on which the given documents are stacked, and the document 
feed and discharge passages are curved in a substantially U-shape, it can 
be made compact and improved in performance and reliability of 
transporting the given documents to be dealt with. The document feeder of 
this invention is provided with at least one guide piece on the document 
tray and curing member close to a document discharge port, thereby to 
prevent the document discharged through the discharge port from colliding 
with the tail end of the stack of documents left on the document tray or 
coming into the stack of documents. The automatic document feeder of the 
present invention is advantageously applicable to various image processing 
devices such as a copying machine, printer, facsimile and image scanner 
and all sorts of devices to which a sheet material is required to be 
automatically fed. 
It is to be understood that the invention is not limited in its application 
to the details of construction and arrangement of parts illustrated in the 
accompanying drawings, since the invention is capable of other embodiments 
and of being practiced or carried out in various ways. Also it is to be 
understood that the phraselogy or terminology employed herein is for the 
purpose of description and not of limitation.