Apparatus for sorting and transporting sheets

An apparatus for sorting and transferring sheets comprises storing means for storing a stack of sheets, first transferring means for transferring a sheet located at an end of the stack of the sheets from the storing means in a first direction, and second transferring means for transferring the next sheet located at the end of the stack of the sheets from the storing means in a second direction. The first and second directions are different from each other. The apparatus for sorting and transferring the sheets is applied; for example, to an automatic original transferring apparatus and a temporary storing tray of a copying machine.

BACKGROUND OF THE INVENTION 
The present invention relates to an apparatus for sorting and transporting 
sheets, an apparatus for automatically transporting original sheets and an 
automatic paper feeding apparatus. More specifically, the present 
invention relates to those apparatuses for storing a stack of sheets. 
Japanese Patent Laying-Open No. 17359/1981, Japanese Patent Laying-Open No. 
74263/1981 and Japanese Patent Laying-Open No. 159859/1985 are examples 
which disclose copy machines as conventional apparatuses which require the 
sorting of a group of stacked sheets. 
The copying machines have a storing part for storing a stack of original 
sheets. The original sheet at the bottom of the group of the original 
sheets is transported by rollers and positioned at the exposure point of 
the copying machine. After exposure, the original sheet is transported by 
rollers and stacked on a stack of the original sheets. In this way, the 
original sheets are circulated from the storing part through the exposure 
point. 
The copy machines produce a two-sided copy corresponding to two one-sided 
original sheets as in the following: First, all the even-numbered pages of 
the original, for example, are copied. The copy sheets are turned and fed 
again to copy the odd-numbered pages on the other side. Accordingly, these 
kinds of copying machines circulate all the original sheets when either 
the even-numbered pages or the odd-numbered pages are copied. Therefore, 
all the original sheets must be circulated twice to make each two-sided 
copy. That is, in the conventional copying machine, the odd-numbered pages 
of the original sheets are only transported, without copy processing, when 
the even-numbered pages are copied, and the even-numbered pages are only 
transported, without processing, when the odd-numbered pages are copied. 
This means the transportation of the original sheets is inefficient and 
the process speed is thus limited. 
A copying machine disclosed in Japanese Patent Laying-Open No. 21073/1980 
comprises an automatic original transporting apparatus having two original 
transport lanes. In this case, when an even-numbered page/sheet of the 
original is transported through a lane and copied, an odd-numbered 
page/sheet of the original is being transported through the other lane 
while the even-numbered page/sheet of the original is being exposed. 
This copying machine, however, has only one exit in the storing part to the 
original transport lanes, so that only after a sheet of the original is 
completely transported out of the storing part can the next sheet of 
original begin to be transported. Further, according to the above 
constitution, the sheet of the original to be copied must be detained 
while the next sheet of the original is being transported. Therefore, the 
conventional copying machine can not transport the sheets of he original 
at high speed. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide an apparatus for 
storing and transporting sheets which has high degree of freedom in terms 
of sheet transportation directions, by which the time of sheet 
transportation is made shorter and various kinds of sheets can be easily 
transported. 
It is another object of the present invention to provide an automatic 
original transporting apparatus in an image forming apparatus which 
transports original sheets in a short period of time, whereby the period 
of the image forming can be shortened. 
(1) An apparatus for sorting and transporting sheets according to the 
present invention comprises: storing means for storing a group of stacked 
sheets; first transferring means for transferring a sheet located at one 
end of the group of stacked sheets from the storing part in a first 
direction; and second transferring means for transferring a sheet located 
at the end of the group of stacked sheets from the storing part in a 
second direction. The first and the second directions are different from 
each other. 
In the apparatus according to the present invention, the first transporting 
means transports a sheet located at one end of the group of stacked sheets 
from the storing means in a first direction. The second transporting means 
transports a sheet located at the end of the group of stacked sheets from 
the transporting means in a second direction which is different form the 
first direction. As a result, the sheets are transported in the different 
directions, so that the degree of freedom in terms of sheet transportation 
directions is increased, shortening sheet transportation time and allowing 
easy transport of various kinds of sheets. 
When the apparatus is used as an automatic original transporting apparatus 
in an image forming apparatus, for example, each of two sheets of original 
can be transported in different directions. As a result, the efficiency of 
transportation of originals is increased, reducing the transportation 
time, and thereby reducing the image forming time. Moreover, when the 
apparatus is used as an automatic material sheet feeding apparatus of an 
image forming apparatus, a sheet of the material paper is transported in 
one direction and another sheet of the material paper is transported in 
another direction. Accordingly, the degree of freedom in terms of feeding 
originals to be processed is increased additionally, thereby reducing the 
image forming time. Further, OHP sheets and their mounts stacked thereover 
can be sorted as one group of sheets. Accordingly, various kinds of sheets 
can be easily transported. 
(2) An automatic original transporting apparatus in an image forming 
apparatus according to the present invention comprises storing means, 
first transferring means, second transferring means and returning means. 
The storing part is for storing a stack of originals. The first 
transferring means is for transferring a sheet of the original located at 
one end of the stack of the originals from the storing part in a first 
direction and positioning the sheet of the original at the exposure point 
of the image forming apparatus. The second transferring means is for 
transferring out of the storing part a sheet of the original located at 
the end of the stack of the originals in a second direction different from 
the first direction. The returning means is for returning the pair of the 
sheets of the original transported out by the first and second 
transferring means in order to stack them on the other end of the stack of 
the originals. 
In the automatic original transporting apparatus in the image forming 
apparatus according to the present invention, the first transferring means 
transports a sheet of the original located at an end of the stack of the 
originals stored in the storing part from the storing part in a first 
direction and positions the sheet at the exposure point of the image 
forming apparatus. The second transferring means transports a sheet of the 
original located at the end of the stack of the originals from the storing 
part in a second direction different from the first direction. Then, the 
returning means returns the pair of the sheets of the original transported 
by the first and the second means to stack them on the other end of the 
stack of the originals. Therefore, since two sheets of the original are 
transported in the different directions at almost the same time, the 
original transporting time is reduced and, as a result, the image forming 
time is reduced. 
The above operation will be described more specifically in case of making a 
two-sided copy from one-sided originals as follows: When the first sheet 
of the original located at one end of the stack of the originals stored in 
the storing part is an even-numbered page of the original, for example, 
the first transferring means transports the even-numbered page of the 
original from the storing part in a first direction and positions the 
sheet at the exposure point of the image forming apparatus. The second 
transferring means transports the next, odd-numbered page of the original, 
located at the end of the stack of the originals from the storing part in 
a second direction different from the first direction. Then, the returning 
means returns the pair of the sheets of the original transferred by the 
first and the second means to stack them on the other end of the stack of 
the originals. Therefore, the odd-numbered page of the original can be 
transferred at almost the same time the even-numbered page of the original 
to be exposed is transferred, so that time is not spent only transporting 
sheets of the original, without a copying process. Time for transporting 
the originals is thus reduced. As a result, the time required for image 
forming is reduced. 
(3) An automatic original transporting apparatus and an automatic sheet 
feeding apparatus in an image forming apparatus according to the present 
invention comprise storing means, transferring means, first feeding means 
and second feeding means. 
The storing means is for storing a stack of copied sheets. The transferring 
means is for transporting a copied sheet located at an end of the stack of 
copied sheets from the storing part in a first direction. The first 
feeding means is for transferring a copied sheet located at the end of the 
stack of the sheets for the storing part in a second direction different 
form the first direction, and positioning the sheet at the image copying 
point of the image forming apparatus. The second feeding means is for 
transferring in the second direction the copied sheet which was 
transferred by the transferring means, through its original position in 
the storing means, after the first feeding means transfers the other 
copied sheet, and positioning the sheet at the image copying point of the 
image forming apparatus. 
For example, in the automatic sheet feeding apparatus of the image forming 
apparatus according to the present invention, the transferring means 
transports a copied sheet located at an end of the stack of the sheets 
stored in the storing means from the storing means in a first direction. 
Then, the first feeding means transfers the next copied sheet located at 
the end of the stack of the sheets from the storing part in a second 
direction and positions the sheet at the image copying point of the image 
forming apparatus. After the first feeding means transfers the other 
copied sheet, the second feeding means transfers the copied sheet which 
was transferred by the transferring means, through its original position 
in the storing part in the second direction, and positions the sheet at 
the image copying point of the image forming apparatus. Therefore, before 
the copied sheet located at the end of the stack in the initial condition 
is transferred to the image copying point, the next copied sheet is 
transferred to the image copying point. As a result, the transporting 
order of the copied sheets can be changed to suit the feeding of the 
original. Accordingly, wasteful transportation of originals which is 
required in the conventional apparatus becomes unnecessary, reducing the 
original processing time, so that the image forming time is reduced. 
The above operation will be described more specifically in the case of 
obtaining a two-sided copy form one-sided originals as follows: First, all 
sheets of the original are fed in an ordinary order to copy the respective 
images onto the copy sheets, and the copied sheets are then turned and 
stored in the storing means of the automatic feeding apparatus. Assuming 
that the first copied sheet located at an end of the stack of the sheets 
stored in the storing part is an even-numbered page, the transferring 
means transfers that copied sheet in a first direction. Then, the first 
feeding means transfers the next copied sheets, copied with the image of 
an odd-numbered page of the original, from the storing part in a second 
direction and places the sheet at the image copying position in the image 
forming apparatus. The copied sheet is copied with the same image of the 
even-numbered page as that of the copied sheet transferred by the 
transferring means. 
Next, the second feeding means transfers the copied sheet transferred by 
the transferring means, through its original position in the storing part 
in the second direction, and places the sheet at the image copying 
position in the image forming apparatus. The copied sheet is copied with 
the same image of the odd-numbered page as that of the copied sheet 
transferred by the first feeding means. 
Repeating the above operation, two two-sided copies can be obtained by 
circulating the original twice, without any loss in the operation. 
Therefore, the operation does not require the time for only transferring 
the sheets of the original without a copying process, so that the 
processing time of the original is reduced and, as a result, the image 
forming time is reduced. 
These and other objects and advantages of the present invention will be 
more fully apparent from the following detailed description.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Embodiment I 
Referring to FIG. 1, which shows an embodiment according to the present 
invention, a copying machine 10 has an automatic original transferring 
apparatus 11 at the top portion. In the right side portion of the copying 
machine 10 in FIG. 1, a bypass plate 12, paper cassette cases 13 and 14, 
and a large size paper cassette case 70 are disposed vertically. Disposed 
in the left side portion of the copying machine 10 is a catch tray 15. 
In about center of the copying machine 10, a photosensitive drum 17 is 
disposed. The photosensitive drum 17 is surrounded by a corona-generating 
device 18, a development system 19, a transfer station 20, a detach 
station 21, and a cleaning system 22, in that order. In a space located in 
the upper portion of the copying machine 10, an exposure device 23 of the 
optical system is disposed. Paper transferring lanes 24 are provided 
between the bypass plate 12, etc. and the transfer station 20. A paper 
transferring system 25 and a fuser assembly 26 are disposed in that order, 
lower than the transfer system 20, in terms of paper flow. A branching 27 
is placed between the fuser assembly 26 and the catch tray 15. Disposed 
above the branching 27 is a turning device 28. The branching 27 can be 
switched between a first position, shown in FIG. 1, for connecting the 
fuser assembly 26 and a paper transferring lane 31 (described later) to 
the catch tray 15, and a second position, for connecting those to the 
turning device 28. The turning device 28 has a bypass lane 39 connected to 
the catch tray 15 for transferring sheets to the catch tray 15, and a 
branching 40 for guiding a sheet stored in the device 28 to either the 
branching 27 or the bypass lane 39. 
In the lower space of the copying machine 10, a temporary storing tray 30 
is disposed, from which the lowermost sheet is forwarded for feeding. 
Between the left end of the temporary storing tray 30 and the branching 
27, a paper transferring lane 31 is disposed. Another paper transferring 
lane 32 connects the right end of the temporary storing tray 30 to a 
middle portion of the paper transferring lane 24. The top end, or the 
lower end in terms of paper flow, of the paper transferring lane 32 is 
connected to the paper transferring lane 24 so that the paper lane 
functions smoothly for feeding the paper to the transfer station 20. 
The temporary storing tray 30 comprises a paper base 33 extending 
horizontally, feeding rollers 34 placed at the right end of the paper 
storage base 33, and a forwarding roller 35 in the right middle portion of 
the paper storage base 33. A pair of side plates 36 is provided near the 
forwarding roller 35 to regulate deviation of papers in the widthwise 
direction (which is the direction perpendicular to the sheet containing 
the drawing). A presser roller 37 is above the forwarding roller 35 and 
presses downwards on the paper stored on the paper storage base 33. An end 
of the paper transferring lane 31 near the temporary storing tray 30 has a 
paper transferring lane 38 which can change the position from which sheets 
fall on the paper base 33 corresponding to the paper size. 
The automatic original transferring apparatus 11 has storing part 42 in the 
middle of a housing 41, in which a stack of original is stored. The right 
end portion and the left end portion of the base of the storing part 42 
have forwarding rollers 43 and 44. The forwarding rollers 43, 44 are 
positioned partially above the base surface of the storing part 42 to 
touch the lower surface of the stack of the original stored in the storing 
part 42. 
Below the storing part 42, a pair of transferring belts 45, 46 are 
disposed. The transferring belt 45 extends between a pair of rollers which 
have a space therebetween in the lateral direction and is circulated by 
the rollers in the direction of the arrow A. The transferring belt 46 
extends between a pair of rollers which has a space therebetween in the 
lateral direction and is circulated by the rollers in the direction of the 
arrow B, and the reverse direction. The bottom surfaces of the 
transferring belts 45 and 46 are faced to a transparent contact glass 47 
which is fixed to the top end of the body of the copying machine 10. The 
exposure point 29 of the exposure device 23 moves from side to side in 
FIG. 1 when it scans a stopped sheet of the original, but it is fixed at 
the point against the left roller of the transferring belt 46 as shown in 
FIG. 1 when it scans a moving sheet of the original. 
In the right end portion of the housing 41, a primary sheet feeding lane 48 
is provided which turns like a "J" to connect the bottom of the storing 
part 42 to the bottom part of the transferring belt 45. An end portion of 
the primary sheet feeding lane 48 near the storing part 42 has feeding 
rollers 49 which consist of a pair of rollers adjacent to the forwarding 
roller 43. In the left end portion of the housing 41, a secondary sheet 
feeding lane 50 is provided which turns like a "J" to connect the bottom 
portion of the storing part 42 to the bottom portion of the transferring 
belt 46. An end portion of the secondary sheet feeding lane 50 near the 
storing part 42 has feeding rollers 51 which consists of a pair of rollers 
adjacent to the forwarding roller 44. Above the secondary sheet feeding 
lane 50, a discharging lane 52 is disposed which has an outlet in the 
upper portion of the storing part 42. The upper end portion of the 
discharging lane 52 in terms of sheet flow is connected to a middle 
portion of the secondary sheet feeding lane 50, and a switching guide 53 
is located at the connecting point. A reversing lane 54 is provided on the 
left of the discharging lane 52. The upper end of the reversing lane 54 in 
terms of sheet flow is connected to the connecting point of the secondary 
sheet feeding lane 50 and the discharging lane 52, and a switching guide 
55 is provided at the connecting point. The lower end of the reversing 
lane 54 in terms of sheet flow is connected to the middle portion of the 
discharging lane 52 to discharge a sheet of the original in the reversing 
lane 54 to the outlet of the discharging lane 52. 
The copying machine 10 has a control unit (not shown) comprising a 
microcomputer and is controlled by that as described below. 
The operation of the above embodiment will be described with reference to 
flow charts shown in FIGS. 2 to 4. For example, there are four sheets of 
original in the storing part 42, the upper surfaces of which are front 
surfaces as shown in FIG. 5A. FIG. 5 is a schematic view showing the 
original in the storing part 42 and copied paper in the temporary storing 
tray 30 and the catch tray 15. In this figure, the surface having a 
triangle has an image, and a number in the triangle indicates the page 
number. 
Referring to FIG. 2, after the program starts, an initial setting, 
including setting an initial sheet size and an initial copy number, is 
inputted through a control panel (not shown) at step S1. At step S2, the 
copy number inputted at the step S1 is stored as X. At step S3, the 
program waits for the copy key to be pushed, which means starting a copy 
operation. After pushing the copy key, the program goes to the next step, 
S4. 
At step S4, it is judged whether the two-sided copy mode was designated at 
step S1. When the two-sided copy was not designated, step S5 proceeds and 
the program finishes after an ordinary copy process is carried out. If the 
two-sided copy mode was designated at step S4, step S6 proceeds, at which 
it is judged whether the original is one-sided or two-sided, depending 
upon a designation at step S1. When the original is two-sided, step S5 
proceeds, and the program finishes after an ordinary copy process is 
carried out. When the original is one-sided at step S6, step S8 in FIG. 3 
proceeds. 
At step S8, the pages of the original are counted. First, the switching 
guides 53, 55 are positioned as shown in FIG. 1. Each sheet of the 
original stacked in the storing part 42 is circulated from the bottom of 
the stack through the primary sheet feeding lane 48, the transferring belt 
45, the transferring belt 46, and the discharging lane 52. While 
circulating the original, a count system (not shown) counts the pages of 
the original. The counted number of pages of the original is stored as "Y" 
and 0 is set "I", which means an actual copy number at step S9. At step 
S10, it is judged whether the number of the original pages is odd or even. 
Since the number of the original pages is even in this case, step S11 
proceeds. 
At step S11, the forwarding rollers 43 and feeding rollers 49 feed the 
sheet of page 4 of the original at the bottom of the storing part 42 to 
the primary sheet feeding lane 48. For this feeding, the transferring belt 
45 circulates in the direction A. Then, the switching guide 53 is shifted 
to open the secondary sheet feeding lane 50, and the forwarding roller 44 
and the feeding rollers 51 feed the sheet of page 3 of the original in the 
storing part 42 to the secondary sheet feeding lane 50. For this feeding 
the transferring belt 46 circulates in the direction B. This process step 
S12 is carried out subsequently after the sheet of the original moves to 
the primary sheet feeding lane 48 and the end of the sheet of the original 
leaves at the forwarding roller 44 at step S11. As a result, the feeding 
of a sheet through the primary sheet feeding lane 48 and the feeding of a 
sheet through the secondary sheet feeding lane 50 are carried out almost 
the same time. That is, according to the embodiment, a sheet of an odd 
page of the original is transferred while a sheet of an even page of the 
original to be exposed is transferred. After the sheet of page 4 of the 
original is set below the transferring belt 45 and the sheet of page 3 of 
the original is set below the transferring belt 46, the transferring belt 
46 subsequently circulates in the direction B. By the circulation, the 
sheets of pages 3 and 4 of the original are transferred to the discharging 
lane 52. During this process, the exposure point 29 of the exposure device 
23 is fixed at the position shown in FIG. 1, so that the sheet of page 4 
of the original is scanned due to its movement, and a material sheet is 
transferred from either the bypass plate 12, the paper cassette case 13, 
14 or 70 to the transfer station 20 at step S13. The image of page 4 of 
the original is transferred to the material sheet at step S14. Further, 
the sheet copied is transferred to the fuser assembly 26 for fusing. At 
step S15, the sheets of pages 3 and 4 of the original are discharged 
subsequently through discharging lane 52 to the storing part 42. 
Meanwhile, the branching 27 is set for the turning device 28, and then the 
copied sheet corresponding to page 4 of the original is turned in the 
turning device 28 and placed on the paper base of the temporary storing 
tray 30 through the paper transferring lane 31. 
At step S16, it is judged whether the sheets of the original have been 
transferred. Since the sheets of pages 1 and 2 of the original have not 
been fed in this case, the program goes back to step S11 again. Then, 
using the sheets of pages 1 and 2 of the original, steps S11 to S15 are 
carried out again. 
After that, step S17 proceeds since it is judged that all the pages of the 
original has been fed at step S16. The momentary condition of the original 
and the copied sheets stored in the storing part 42, the temporary storing 
tray 30, and the catch tray 15, respectively, is shown in FIG. 5B. 
The sheet of page 3 of the original at the bottom of the storing part 42 is 
transferred through the main sheet feeding lane 48 at step S17. Then, the 
switching guide 53 is rotated to open the secondary sheet feeding lane 50 
and the sheet of page 4 pages in the storing part 42 is transferred 
through the secondary sheet feeding part 50. In this case, the process of 
step S18 starts subsequently after the sheet of the original moves to the 
primary sheet feeding lane 48 or the end of the sheet leaves the 
forwarding roller 44. Therefore, feeding a sheet through the primary sheet 
feeding lane 48 and feeding a sheet through the secondary sheet feeding 
lane 50 are carried out at almost the same time. That is, the sheet of an 
even-numbered page of the original is transferred while the sheet of an 
odd-numbered page of the original to be exposed is transferred. Just after 
the sheet of page 3 of the original is set below the transferring belt 45 
and the sheet of page 4 of the original is set below the transferring belt 
46, the transferring belt 46 circulates in the direction B. By this 
circulation, the sheets of pages 3 and 4 of the original are transferred 
subsequently to the discharging lane 52. During the process, the moving 
sheet of page 3 of the original is being scanned at the exposure position 
29 in FIG. 1, since the exposure position 29 of the exposure device 23 is 
fixed at the point shown in FIG. 1. 
At step S19, the sheet of the material paper copied with the image 
corresponding to page 4 of the original in the sheets stored in the 
temporary storing tray 30 is transferred to the transfer system 20 in 
synchronization with the timing of the exposure of the sheet of page 3 of 
the original. Then, the image of page 3 of the original is transferred to 
the sheet of the material paper at step S20. The copied sheet is 
transferred to the fuser assembly 26 to be fused. Then, the sheets of 
pages 3 and 4 of the original are discharged subsequently to the storing 
part 42 through the discharging lane 52 at step S21. Meanwhile, the 
branching 27 is set for the catch tray 15 and the copied sheet having the 
images of pages 3 and 4 of the original is discharged on the catch tray 
15. 
At step S22, it is judged whether all the sheets of the original have been 
fed. Since the sheets of page 1 and 2 of the original have not been fed in 
this case, the program goes back to step S17. Then, using the sheets of 
page 1 and 2 of the original, steps S17 to S21 proceed again. 
After that, when it is detected that all the sheets of the original have 
been fed at step S22, step S23 proceeds. FIG. 5C shows the condition at 
the moment of the original and copied sheets stored in the storing part 
42, the temporary storing tray 30 and the catch tray 15, respectively. As 
shown in FIG. 5C, the order of the originals stacked in the storing part 
42 is the same as that before transferring, and the copied sheets copied 
on both sides are stacked in the catch tray 15 in the correct order. 
Since the two-sided copying corresponding to all the originals has been 
carried out at this moment, "1" is added to "I" at step S23. Then, it is 
judged whether "X" is equal to "I" at step S24. If these are equal, the 
program finishes, because the predetermined number of copies was obtained. 
Meanwhile, if "X" is not equal to "I" at step S24, the processes from step 
S11 to step S22 are carried out until "X" equals "I" at step S24. 
In the above, four sheets of the original were used so as to understand the 
operation easily. Other numbers of sheets of original, however, can be 
used if the number is even. 
When the number of the original pages counted at step S8 is odd, the 
program moves from step S10 to step S25 in FIG. 4. At step S25, a sheet of 
an odd-numbered page of the original at the bottom of the paper 
transferring lane 24 is transferred through the sheet feeding lane 48. 
Then the sheet of the original is transferred through the transferring 
belts 45 and 46 and scanned at the fixed position shown in FIG. 1, since 
the exposure point 29 of the exposure device 23 is fixed at the point 
shown in FIG. 1. 
A sheet of the material paper is transferred from either the bypass plate 
12, or the paper cassette cases 13, 14 or 70, to the transfer station 20 
in synchronization with the scanning of the original at step S26. Then, at 
step S27, the image corresponding to the sheet of the odd-numbered page of 
the original is transferred to the sheet of the material paper, and the 
sheet of the material paper is transferred to the fuser assembly 26 to be 
fused. Further, at step S28, the sheet of the odd-numbered page of the 
original is discharged through the discharging lane 52 to the storing part 
42. Meanwhile, the branching 27 is set for the catch tray 15, and the 
sheet copied with the image of the odd-numbered page of the original is 
discharged to the catch tray 15. 
After the operation involving the sheet of the odd-numbered page of the 
original positioned at the bottom of the storing part 42, the number of 
the rest of the originals becomes even. Therefore, at step S29, two-sided 
copies can be obtained by processing the remaining even number of sheets 
of the original through the execution of steps S11 to S22. After the 
execution, the sheets of the original in the storing part 42 are stored in 
the same order as the order before processing, and the sheets of the 
two-sided copy are stacked in the catch tray 15 in the correct order. 
Since all of the two-sided copies corresponding to all the pages of the 
original have been finished at that moment, "1" is added to "I" at step 
S30. Then, at step S31, it is judged whether "X" is equal to "I". If these 
are equal, the program is finished because the predetermined number of 
copies has been obtained. If "X" does not equal "I" at step S31, steps S25 
to S29 are executed until "X" equals "I" at step S31. 
According to the embodiment, since the next sheet of the original can be 
transferred while a sheet of the original to be exposed is transferred, 
the time used only for transferring the sheet of the original without a 
copying process is not required, so that the processing time of the 
originals is thus shortened. By this means, the image processing time is 
also shortened. Embodiment II 
FIG. 6 shows the second embodiment according to the present invention. In 
FIG. 6, the same members as those of the copying machine 10 shown in FIG. 
1 have the same reference numbers. 
The embodiment of FIG. 6 has an automatic original transporting apparatus 
11 which is a conventional one of the bottom-paper advancing type. The 
automatic original transporting apparatus 11 comprises a storing part 61, 
feeding rollers 62 located at the outlet of the storing part 61, a sheet 
feeding lane 63 receiving a sheet from the feeding rollers 62, a 
transferring belt 64 opposed to the contact glass 47 and receiving a sheet 
from the sheet feeding lane 63, and a discharging lane 65 receiving a 
sheet from the end of the transferring belt 64 near the exposure position 
29. The outlet of the discharging lane 65 is disposed at the upper portion 
of the storing part 61. A reversing lane 67 is connected through a 
switching guide 66 to the discharging lane 65. 
In FIG. 6, the temporary tray 30 has a retracting roller 71 located at the 
left end portion of the base 33. A paper discharging tray 16 is provided 
on the left of the paper storage base 33 and is connected to it. 
Now, the operation of the embodiment will be described referring to the 
flow chart shown in FIGS. 7 to 11. It is assumed that there are four 
sheets of the original stored in the storing part 61 as shown in FIG. 12A. 
FIG. 12 schematically shows a condition of the sheets of the original and 
the material paper in the storing part 61, the temporary storing tray 30, 
and the catch tray 15. Also in this figure, the surface of the sheet 
having a triangle has a copied image, and the number in each of the 
triangles indicates the page number. 
Referring to FIG. 7, after the program starts, the initial conditions, such 
as the kind of paper and the number of copies, are set by inputting the 
information through a control panel (not shown) at step S41. The number of 
copies inputted at step S41 is stored as "X" at step S42. The program 
waits for the pressing of the copy key, which means the start of a copy 
operation at step S43. After the copy key is pressed, step S44 proceeds. 
At step S44, it is judged whether the copy mode for OHP sheets is 
designated. When the ordinary copy mode is designated, step S45 is 
executed. At step S45, it is judged whether the two-sided copy mode was 
designated at step S1. If the two-sided copy mode was not designated, step 
S46 is executed to perform an ordinary copy process, and the program is 
finished. If the two-sided copy mode was designated at step S45, step S47 
is executed and it is judged whether the original is either a one-sided 
original or a two-sided original at step S47, depending upon the 
designation at step S1. When the original is two-sided, step S46 is 
executed to perform an ordinary copy process and then the program ends. 
When a one-sided original is detected at step S47, step S48 is executed to 
judge whether the number of copies is more than one. If the number of 
copies is 1, step S46 is executed to perform an ordinary copy process and 
then the program ends. If the number of copies is more than 1 at step S48, 
step S49 in FIG. 8 proceeds. 
At step S49, the number of the original sheets is counted. In this process, 
the switching guide 66 is set as shown in FIG. 6, and the stack of the 
originals in the storing part 61 is circulated one by one from the bottom 
through the feeding rollers 62, the sheet feeding lane 63, the 
transferring belt 64 and the discharging lane 65. During the circulation, 
a counting device (not shown) counts the number of the original sheets. 
Then, the counted number of the original sheets is stored as "Y" and 0 is 
set to "I" which determines the number of copies actually carried out at 
step S50. 
At step S51, page 4 of the original sheets, located at the bottom of the 
storing part 61, is transferred by the feeding rollers 62 and the 
transferring belt 64. Since the exposure point 29 of the exposure device 
23 is fixed at the point shown in FIG. 6, the sheet of page 4 is exposed 
at the shown point during the movement of the sheet. Meanwhile, a sheet of 
the material paper is transported from either the bypass plate 12, or the 
paper cassette case 13, 14 or 70, to the transfer station 20. Then, at 
step S52, the image corresponding to page 4 of the original is transferred 
to the material paper, and the paper is transported to the fuse assembly 
26 to fuse the image. At step S53, the sheet of page 4 of the original is 
discharged through the discharging lane 65 to the storing part 61. 
Meanwhile, the branching 27 is switched for the turning device 28, and the 
sheet copied with the image of page 4 of the original is turned in the 
turning device 28. After that, the sheet is placed on the paper storage 
base 33 of the temporary storing tray 30 through the paper transferring 
lane 31. 
It is judged whether the number of transported sheets of the original 
becomes "Y" at step S54. If the number does not become "Y", the processes 
from step S51 to step S53 are carried out again since all the sheets of 
the original have not been circulated. When all the sheets of the original 
have been circulated, the number of the sheets of the original transported 
becomes "Y" at step S54, so that step S55 is executed. At step S55, the 
branching 27 is switched to the catch tray 15. Then, it is judged whether 
the number of the sheets of the original "Y" is odd or even at step S56. 
In this case, the number of the originals is even, so that step S57 
proceeds. The momentary condition of the original and the material paper 
as stored in the storing part 61, the temporary storing tray 30 and the 
catch tray 15, respectively, is shown in FIG. 12B. 
At step S57, the sheet of page 4 of the original at the bottom of the 
storing part 61 is transported from the primary sheet feeding lane 48. 
Meanwhile, just after starting the paper feeding operation at step S57, 
step S58 and step S59 proceed approximately in parallel. At step S58, the 
forwarding roller 35 rotates in the direction of the arrow X, and the 
sheet of the material paper copied with an image of page 4 of the original 
positioned at the bottom of the stack on the temporary storing tray 30 
moves to the left. Further, the retracting roller 71 rotates in the 
direction of the arrow Y, so that the sheet of the material paper moves to 
the left. Accordingly, the next sheet of the material paper copied with 
the image of page 3 of the original comes into contact with the forwarding 
roller 35. Next, at step S59, the forwarding roller 35 rotates in the 
reverse direction to the arrow X, and the feeding rollers 34 start 
rotating, so that the sheet of the material paper copied with the image of 
page 3 of the original is fed to the transfer station 20. Subsequently, at 
step S60, the transfer station 20 transfers the image of page 4 of the 
original to the fed sheet of the material paper and the fuser assembly 26 
fuses it. At step S61, the sheet of page 4 of the original is discharged 
through the discharging lane 65 to the storing part 61. The branching 27 
is switched to the turning device 28. The sheet of the material paper is 
turned by the bypass lane 39 and the branching 40 and discharged to the 
catch tray 15. 
At step S62, the sheet of page 3 of the original at the bottom of the 
storing part 61 is transported through the sheet-feeding lane 63. Just 
after the feeding operation starts at step S62, the process at step S63 
starts. At step S63, the retracting roller 71 starts rotating in the 
reverse direction to the arrow Y, so that the sheet copied with the image 
of page 4 of the original and located at the retracted position is moved 
to the right. Further, the forwarding roller 35 starts rotating in the 
reverse direction to the arrow X to move the sheet to the right. Then, by 
the rotation of the feeding rollers 34, the sheet copied with the image of 
page 4 of the original is transported to the transfer station 20. 
Subsequently, at step S64, the sheet fed to the transfer station 20 is 
copied with the image of page 3 of the original and fused in the fuser 
assembly 26. At step S65, the sheet of page 3 of the original is 
discharged through the discharging lane 65 to the storing part 61. The 
copied sheet of the material paper is discharged to the catch tray 15, 
since the branching 27 is switched to the catch tray 15. 
At step S66, it is judged whether the number of the sheets of the original 
becomes "Y". If the number does not become "Y", steps S57 to S65 are 
executed because all the sheets of the original have not been circulated. 
When all the sheets of the original have been circulated, step S67 in FIG. 
9 proceeds, since the number of the fed sheets of the original becomes "Y" 
at step S66. This momentary condition of the original and the material 
paper as stored in the storing part 61, the temporary storing tray 30 and 
the catch tray 15, respectively, is shown in FIG. 12C. As shown in FIG. 
12C, after all the sheets of the original are circulated twice, two 
two-sided copies corresponding to all the sheets of the original are 
obtained. As a result, the sheets of the original are stacked in the 
storing part 61 in the correct order, and pairs of two-sided copied sheets 
are stacked in the catch tray 15 in the correct order. 
Then, 2 is added to "I" at step S67. At step S68, it is judged whether "X" 
is equal to "I". If these are equal, the program ends because the 
predetermined number of copies has been obtained. If "X" does not equal 
"I" at step S68, step S69 is executed. At step S69, it is judged whether 
"X" is equal to "I+1". If these are equal, another ordinary copying 
process is carried out at step S70, because one more copy is required to 
obtain the predetermined number of copies, and then the program ends. If 
"X" does not equal "I +1" at step S69, steps S51 to S66 are carried out 
again because more than one copy is further required to obtain the 
predetermined number of copies. By this sequence, two more copies can be 
obtained. The sequence from step S51 to S66 is carried out until "X" is 
equal to "I" at step S68 or "X" is equal to "I+1" at step S69. Lastly, the 
program ends through step S68 or step S70. 
In the above explanation, four sheets of original are used for ease of 
understanding, although another number of sheets of the original can be 
used, so long as the number of sheets of the original is even. 
If the counted number of the original sheets is odd at step S49, the 
program from step S56 to step S71 in FIG. 10 is executed. At step S71, the 
sheet copied with the image of the odd-numbered page of the original 
located at the bottom of the temporary storing tray 30 is transferred by 
the rotation of the forwarding roller 35 and the feeding rollers 34. In 
this case, it is not required to copy an image to the back surface of the 
material paper, so that the sheet of the material paper is transported at 
step S72 without a copying process. At step S73, the branching 27 is 
switched to the turning device 28. The sheet of the material paper is 
turned by the bypass lane 39 and the branching 40 and discharged with the 
upper surface copied. 
At step S74, the sheet of the odd-numbered page of the original placed at 
the bottom of the storing part 61 is transported through the sheet feeding 
lane 63. Meanwhile, at step S75, a sheet of the material paper is 
transported from either the bypass plate 12, or the paper cassette case 
13, 14 or 70 to the transfer station 20, in synchronization with the 
scanning of a sheet of the original. Then, at step S76, the image 
corresponding to the sheet of the original is transferred to the sheet of 
the material paper, and the sheet of the material paper is transported to 
the fuser assembly 26 to be fused. At step S77, the sheet of the original 
is discharged through the discharging lane 65 to the storing part 61. 
Meanwhile, the branching 27 is switched to the catch tray 15, so that the 
copied sheet is discharged to the catch tray 15. 
After the copy process for the sheet of the odd-numbered page of the 
original located at the bottom of the storing part 61, the number of the 
remaining sheets of the original becomes even. Therfore, by executing 
steps S57 to S66, the copying process on the remaining even-numbered 
sheets of the original is carried out and two two-sided copies are 
obtained. That is, after all the sheets of the original are circulated 
twice, two two-sided copies corresponding to all the sheets of the 
original are obtained. In this case, the sheets of the original are 
stacked in the storing part 61 in the correct order, and pairs of the 
two-sided copies are stacked in the catch tray 15 in the correct order. 
Lastly, the processes of steps S67 and S68 are carried out, and the program 
ends through the processes of steps S69 and S70, if necessary. 
Now the copying process for OHP sheets will be described. In the case of 
OHP sheets, a stack consisting of OHP sheets and their mounts stacked 
alternately is set on the paper storage base 33 of the temporary storing 
tray 30. Although, in the following description, the sheet group has a 
mount at its bottom, a sheet group having an OHP sheet at its bottom can 
be used for one of the embodiments according to the present invention. 
In this case, depending upon the setting at step S41 in FIG. 7, the program 
is executed from step S44 to step S78 in FIG. 11. At step S78, a sheet of 
the original is transported in the same manner as the above transportation 
of a sheet of the original. Then, at step S79, the mount located at the 
bottom of the sheet group on the paper storage base 33 is discharged to 
the mount discharging tray 16 by the forwarding roller 35 rotating in the 
direction X and the retracting roller 71 rotating in the direction Y. At 
step S80, the OHP sheet located at the bottom of the sheet group on the 
paper storage base 33 is transported to the transfer station 20 by the 
forwarding roller 35 rotating in the reverse direction to the direction X 
and the feeding rollers 34 rotating subsequently. Next, at step S81, the 
OHP sheet fed to the transfer station 20 is copied with the image of the 
sheet of the original provided by the automatic original transporting 
apparatus 11 and is fused in the fuser assembly 26. At step S82, the 
branching 27 is switched to the catch tray 15 and the copied OHP sheet is 
discharged to the catch tray 15. At step S83, it is judged whether "X" is 
1. If "X" is not 1, "X" is decreased by 1 at step S84, and then steps S79 
through S82 are executed again. If "X" is 1 at step S83, the program moves 
to step S85 because the predetermined number of copies has been obtained. 
At step S85, it is judged whether all the sheets of the original have been 
transported. If not all the sheets of the original have been transported 
at step S85, steps S78 through S83 are carried out to copy the next sheet 
of the original. When all the sheets of the original have been copied at 
step S85, the program ends. 
As described above, since one sheet of the material paper is transported in 
one direction and another sheet is transported in another direction in 
this embodiment, the sheets of the original can be efficiently circulated 
to obtain two-sided copies in reduced time. Therefore, time used for the 
sheets of the original to be transported only is not required, so that the 
processing time of the original is reduced and, as a result, the image 
processing time is reduced. When the stack of the OHP sheets and mounts as 
a sheet group is used, the OHP sheets and the mounts can be sorted. 
Therefore, these kinds of sheets can be easily transported. 
Other Embodiments 
(a) When the present invention is applied to a copy machine which can make 
a plurality of copies by one process of exposure to the original, it is 
easy to obtain a large number of copies. 
(b) A sorter can be provided instead of the catch tray 15. The copied 
sheets are discharged to the sorter. In this case, controlling the sorter 
for sorting the copied sheets in terms of the same page, and controlling 
the sorter for sorting the sheets in terms of a group corresponding to the 
group images of the original can be provided. 
(c) The above embodiments show that the sheets of the original or material 
paper are alternately transported in directions reverse to each other. 
However, the present invention is not limited to that. For example, the 
sheets can be transported in one direction which is in a sideward 
direction to the other direction, or diagonal to the other direction. 
(d) An embodiment shown in FIG. 13 can be used as an embodiment according 
to the present invention. 
In FIG. 13, the same members as in the above embodiments have the same 
reference numerals. Further, in the embodiment of FIG. 13, an automatic 
original transporting apparatus 80 comprises a forwarding roller 81 and a 
retracting roller 82. Although the apparatus 80 receives a stack of the 
original, the rollers 81 and 82 have the same function as the rollers 35 
and 81 in FIG. 6. In this embodiment, a sheet of the original located at 
the bottom of the stack stored in the storing part 83 is retracted first 
by the retracting roller 82, and then the next sheet of the original at 
the bottom is transferred to the exposure point 29 by the roller 81. After 
that, by rotating the roller 82 in reverse and then rotating the roller 
81, the retracted sheet of the original is transported to the exposure 
point 29. Using this method, the situation of the original and material 
paper is changed as shown in FIGS. 14A, 14B and 14C. 
According to this embodiment, the same effect as the above embodiments can 
be obtained. 
Various details of the invention may be changed without departing from its 
scope. Furthermore, the foregoing description of the preferred embodiment 
according to the present invention is provided for the purpose of 
illustration only, and not for the purpose of limiting the invention being 
defined by the appended claims.