Composite copier with trimming and masking modes of operation

A composite copier has keys for selecting trimming and masking modes of operation whereby trimming and masking can be effected with respect to a specified area of an original image. The control system of the copier includes a memory device which remembers which of the modes has been selected and which area has been specified. After a copying process is effected on a copy sheet in the selected mode, the same sheet is recirculated back to the processing section for a second copying process with respect to the same area but from another original and in the other mode of operation.

BACKGROUND OF THE INVENTION 
This invention relates to a composite copier for combining two original 
images and forming their composite copy on a single copy sheet. 
Among multi-functional copiers, there are those which can carry out 
trimming and masking. With a copier of this type, keys and the like 
provided on the control panel are operated to specify an area and the 
trimming mode of operation is used to copy only the image inside this 
specified area while the image outside is erased. The masking mode of 
operation is used to copy only the image outside a specified area. By 
using a copier thus structured, so-called composite copying can be 
effected whereby images from two original documents are combined to form a 
composite image on a single sheet of copy paper. 
With a conventional copier, composite copying is effected by first 
selecting either the trimming or the masking mode of operation and then 
specifying an image area, the first copying process being carried out 
thereupon. Subsequently, the original document is replaced by another 
original, the other of the aforementioned two modes is selected, the image 
area is specified again, the copy sheet which has just been subjected to 
the first copying process is taken out of the discharge section and set in 
the paper supply section again and the second copying process is 
thereafter carried out. In summary, a complicated series of steps must be 
followed with a conventional composite copier to obtain a composite copy. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a composite 
copier which can simplify the composite copying process by storing the 
mode of operation and an image area for the first copying process, 
changing the mode of operation for the second copying process with respect 
to the same image area and leading the once processed copy sheet into a 
recirculating route such that the second copying process can be carried 
out continuously and that the steps of setting a second mode of operation 
and feeding the copy paper again can be dispensed with. 
A composite copier of the present invention which can achieve the above and 
other objects comprises area storage means for storing area data defining 
a specified area of an original image, mode selecting means for selecting 
between the trimming and masking modes of operation, mode storing means 
for storing the selected mode, paper recirculating means for recirculating 
a copy sheet after a first copying process back to the processing section 
for a second copying process, and mode switching means for activating the 
paper recirculating means for composite copying, activating the mode 
stored in the mode storing means with respect to the specified area for 
the first copying process and activating the other mode for the second 
copying process. With a copier thus structured, the image area of an 
original with respect to which trimming and masking are effected is stored 
in the area storing means, the selection between the trimming and masking 
modes of operation made by the mode selecting means is stored in the mode 
storing means, a once-processed copy sheet is sent back to the processing 
section by the paper recirculating means such that copying process can be 
carried out continuously for the second time, and the two copying 
processes on the same copy sheet are effected in different modes but with 
respect to the same area by the operation of the mode switching means.

DETAILED DESCRIPTION OF THE INVENTION 
With reference to FIG. 1 which is a schematic frontal sectional view of a 
composite copier embodying the present invention, a photosensitive drum 22 
is disposed at the center part inside the copier housing 21 and forms a 
processing section 27 together with a primary charger 23, a developing 
unit 24, an image transfer-paper removal charger 25 and a cleaning unit 26 
along its outer periphery. The processing section 27 also includes a 
blanking lamp 23a for providing light to a portion of the surface of the 
photosensitive drum 22 other than the area where an image is formed such 
that latent images are erased and adsorption of developing agent is 
prevented from there. Paper cassettes 28 and 29 and a tray 30 for manual 
paper feed are provided on a side surface of the housing 21 and form a 
paper supply section 31. The paper supply section 31 also includes paper 
feed rollers 32-34 for delivering paper from either one of the cassettes 
28 and 29 or the tray 30. A fixing unit 35 composed of a pair of rollers 
is inside the housing 21 near the other side surface. A copy paper sheet, 
after passing through this fixing unit 35, is discharged from a paper 
discharge section 37 by paper discharge rollers 36 to the exterior. 
Rollers 38-40 and a conveyer belt 41 are provided along a principal paper 
transportation route 42 defined between the paper supply section 31 and 
the paper discharge section 37 through the processing section 27. 
A sorter 51 is attached to the side surface of the housing 21 opposite the 
paper discharge section 37. Inside the sorter 51 are conveyer rollers 
52-54, switchback rollers 55-57 and discharge rollers 58. The switchback 
rollers 55-57 are rotatable in both (positive and negative) directions and 
form a switchback route 61. A flapper 59 is provided between the conveyer 
rollers 52 and the discharge rollers 58 and another flapper 60 is provided 
between the conveyer rollers 54 and the switchback rollers 57. Each of the 
flappers 59 and 60 can assume two positions such that an incoming copy 
sheet can be directed selectably in either of two directions. The upper 
flapper 59 serves to direct a copy sheet discharged from the paper 
discharge section 37 selectably either to the discharge rollers 58 or to a 
secondary paper transportation route 62. The lower flapper 60 serves to 
direct a copy sheet which has passed through the secondary route 62 
selectably either to the switchback route 61 or into a cabinet 71. 
Inside the cabinet 71 is an intermediate tray 82 provided with paper 
introducing rollers 73-76, paper transporting rollers 77 and 78 and 
flappers 79-81. The flappers 79-81 are movably supported and the one of 
those corresponding to the size of the paper to be dropped into the 
intermediate tray 72 is moved up from the position shown in FIG. 1. The 
paper introducing rollers 73-76, the intermediate tray 72 and the paper 
transporting rollers 77 and 78 serve to extend the secondary route 62 to 
the paper supply section 31, thereby connecting the paper discharge 
section 37 with the paper supply section 31. 
In summary, the principal paper transportation route 42 is formed inside 
the housing 21 and the secondary route 62 is formed inside the sorter 51 
and the cabinet 71. In the ordinary one-side copying process, each copy 
sheet delivered from the paper supply section 31 is passed through the 
principal route 42 and discharged from the discharge section 37 by the 
discharge rollers 58. 
In the case of a composite copying process whereby images from a plurality 
of original documents are formed on a single sheet of copy paper, the copy 
sheet which has passed through the processing section 27 is directly led 
into the intermediate tray 72 through the secondary route 62. After the 
original is replaced, the copy sheet stored in the intermediate tray 72 is 
passed between the paper supply section 31 and the processing section 27 
by the rollers 77 and 78 and delivered to the processing section 27 by the 
rollers 38 and 40. After thus passing through the processing section 27 a 
desired plural number of times, the copy sheet is discharged from the 
paper discharge section 37 by the discharge rollers 58. The flappers 59 
and 60, the intermediate tray 72 and the paper transporting rollers 77 and 
78 form what may hereinafter be referred to as the paper recirculating 
means. 
With reference next to FIG. 2 which is a block diagram of the control 
section (not shown in FIG. 1) of the composite copier described above, a 
control panel 5 is provided with a composite copying key 12, a trimming 
key 13 and a masking key 14, and when any of these keys is operated, a 
corresponding signal is transmitted from the panel 5 through an I/O 
interface 4 to be received by a central processing unit CPU 1. The 
composite copying key 12 is operated when it is desired to copy images 
from two original documents onto a single sheet of copy paper. The 
trimming key 13 is for transmitting a signal to switch on the blanking 
lamp 23a such that images outside a predefined area will not be copied. 
The masking key 14 is for transmitting another signal to switch on the 
blanking lamp 23a such that images inside a predetermined area will not be 
copier. Numeric keys 15 are used for predefining such an area. 
Data on the position of the area predefined by operating the numeric keys 
15 or the like are stored in a preassigned memory area M4 of a 
random-access memory RAM 3. A read-only memory ROM 2 is connected to the 
CPU 1 and stores programs for the various constituent units of the copier. 
The CPU 1 transmits control data according to such programs to a solenoid 
driver 7, a blanking lamp driver 6, etc. through the I/O interface 4. The 
solenoid driver 7 is adapted to control the motion of the flappers 59 and 
60 by solenoids SOL1 and SOL2. The blanking lamp driver 6 controls the 
blanking lamp 23a depending on whether trimming or masking mode of 
operation has been selected and what area has been predefined. The 
aforementioned memory area M4 represents what is referred to as area 
storing means in the claims and the trimming and masking keys 13 and 14 as 
mode selection means. 
FIG. 3 is a flow chart showing the operations of the composite copier 
described above. When the composite copying key 12 is operated (n1), a 
flag F2 is set in memory area M2 of the RAM 3 (n2). This flag F2 is for 
indicating whether the composite copying mode of operation has been 
selected or not, being set if this mode of operation is selected. Next, it 
is checked whether the masking key 14 has been operated (n3) and, if it is 
found to have been operated, another flag F1 is set in memory area M2 of 
the RAM 3 (n4) and the processing in the masking mode is carried out (n5). 
This flag F1 is for indicating which of the two modes, trimming or 
masking, has been selected, being set if the masking mode is selected. In 
Step n5, the blanking lamp 23a is so controlled that the area to be later 
defined will be exposed to light for a predetermined period of time. 
If it is determined that the masking key 14 has not been operated (NO in 
n3), it is checked whether the trimming key 13 has been operated (n8). If 
the trimming key is found to have been operated, the processing in the 
trimming mode is carried out (n9) with the blanking lamp 23a so controlled 
that areas other than the area to be later defined will be exposed to 
light for a predetermined period of time. If neither the masking key 14 
nor the trimming key 13 has been operated, some other processing is 
carried out (n10). 
When the numeric keys 15 are operated by the operator to enter area data, 
such data are stored in memory area M4 of the RAM 3 (n6). Thereafter, the 
system waits for the print switch (not shown) to be operated and the 
copying process is started when it is detected that the print switch has 
been operated (YES in n7). First, the flag F2 is checked (n11) to 
determine whether the composite copying mode has been selected. If the 
composite copying mode is found to have been selected, not only is a copy 
paper transported in from the paper supply section 31 (n12) but the 
solenoids SOL1 and SOL2 are switched on (n13) and a counter N is cleared 
(n14), N denoting also the content of this counter. The counter N is at 
memory area M1 of the RAM 3 and serves to count the number of copy sheets 
on which images are transferred in the case of a composite copying mode of 
operation. The paper route now opens from the paper discharge section 37 
to the secondary route 62 and further into the intermediate tray 72 
because the solenoids SOL1 and SOL2 are switched on such that processed 
copy sheets will become stored in the intermediate tray 72. 
Next, an original document for copying is supplied and the content of the 
counter is increased by 1 (n15). Thereafter, the copying process is 
repeated for a set number of sheets (n16 and n17) and the copy sheets onto 
which copying has been effected are temporarily stored in the intermediate 
tray 72. 
After the set number of sheets are thus processed, the content of the 
counter N is checked (n18). If N has not reached 2, the condition of the 
flag F1 (or the content of the memory area M2) is checked (n19). If the 
flag F1 is in the set condition, operations of the trimming mode are 
carried out (n20) and if the flag F1 is in the reset condition, operations 
of the masking mode are carried out (n21). Next, the area data stored in 
the memory area M4 are retrieved (n22), a copy sheet is transported out of 
the intermediate tray 72 (n23), the solenoids SOL1 and SOL2 are switched 
off (n24) and the next original is placed to be copied (n15). From this 
time on, copy sheets are sequentially supplied from the intermediate tray 
72 and the processed copy sheets are discharged to the exterior since the 
solenoid SOL1 is in the OFF condition. The counter N is checked again 
(n18) after the processing described above is completed for the set number 
of times (n17) and, if N is found to have reached 2, the system is ready 
for the beginning of the next copying job. 
If the flag F2 is found to be in the reset condition (NO in n11) after the 
print switch is operated (n7), some other processing is carried out (n25). 
In the above explanation by way of FIG. 3, Steps n3-n5, n8, n9, n13, 
n19-n21 and n24 are operations by the mode selection means of the present 
invention. If the masking mode is selected, the first original is 
processed in the masking mode and the second original is processed in the 
trimming mode. If the trimming mode is selected, on the other hand, the 
first original is processed in the trimming mode and the second original 
is processed in the masking mode. Consider an example wherein originals 
shown in FIGS. 4(A) and (B) are used to obtain a composite shown by FIG. 
4(C). In this situation, the area at the center in FIG. 4(A) is specified 
in terms of the coordinates of positions a, b, c and d and the trimming 
key 13 is operated. This causes only the image inside the designated area 
of the first original shown in FIG. 4(A) to be formed on a copy sheet. 
Thereafter, the second original shown in FIG. 4(B) is processed in the 
masking mode such that only the image outside the designated area is 
formed on the same copy sheet. As a result, an image shown in FIG. 4(C) 
can be obtained, as desired. 
In summary, the choice between the trimming and masking modes for the first 
original is stored in a mode storing means and data for specifying the 
position of the selected area are stored in the area storing means. When a 
composite copy is desired, paper recirculating means are used to lead each 
sheet of copy paper back to the processing section for the second time 
such that a copying process is carried out first in the mode stored in the 
mode storing means with respect to the area specified by the data stored 
in the area storing means. With respect to the second original, the 
copying process is carried out in the other mode such that masking and 
trimming modes of operation are carried out with respect to the same area 
of the two originals and images from them can be formed on a single copy 
sheet. The operator is required to select a mode and define an area only 
once and after the copying operation is started, there is not need to 
manually move the copy sheets. In short, composite copying can be effected 
easily by a copier of the present invention. 
The foregoing description of a preferred embodiment of the invention has 
been presented for purposes of illustration and description. It is not 
intended to be exhaustive or to limit the invention to the precise form 
disclosed, and many modifications and variations are possible in light of 
the above teaching. Such modifications and variations that may be apparent 
to a person skilled in the art are intended to be included within the 
scope of this invention.