JPH0228149B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming apparatus that forms images on the first and second surfaces of a sheet.

Conventionally, as seen in Japanese Patent Publication No. 49-36264, there is a system in which a sheet whose first side has been copied is led to an intermediate storage section, and then the second side is copied in the same manner as the first side. However, since it takes time to guide the paper to the intermediate storage section, the start of copying the second side may be delayed.
Furthermore, there is a method in Japanese Utility Model Publication No. 47-36123 that speeds up the roll paper after recording is completed, and in Japanese Patent Application Laid-open No. 49-10046 there is a method that speeds up the roll paper during the charging process. However, since neither of these methods sequentially forms an image on the first and second surfaces of the sheet, it is not possible to quickly respond to the continuous feeding of sheets with images formed on the first surface.

The present invention eliminates the above drawbacks by feeding a sheet from a storage unit, forming an image on the first side of the sheet, and then forming an image on the second side of the sheet without ejecting the sheet.
a first process means for transporting the sheet to a preparation position for forming an image on a surface; and a second process means for feeding the sheet from the preparation position, forming an image on a second surface of the sheet, and then discharging the sheet. In the image forming apparatus, the first process means includes a rotating means for transporting the sheet with an image formed on the first surface to the preparation position, a control means for controlling the rotational operation of the rotating means, and a timer means. Then, by the above control means,
While conveying the sheet with the image formed on the first surface, the rotating means is reversely rotated to reverse the traveling direction of the sheet, and the rotating means is rotated at high speed to convey the sheet with the image formed on the first surface. The image forming apparatus is characterized in that the image forming apparatus is configured to bring the image forming apparatus to the preparation position at high speed, and further to cause the high speed rotation of the rotation means to be terminated by the timer means.

As a result, even if sheets with images formed on the first side are fed one after another, they can be correctly and quickly stored in the preparation position for forming an image on the second side.

The present invention will be described in detail below with reference to one embodiment.

This embodiment is a transfer-type electronic copying machine that employs a document table fixing system and can easily copy thick originals and three-dimensional objects.

The operation of the copying machine will be explained with reference to FIG.

The original 3 is placed on the transparent plate 2 of the original table, and the optical system is composed of movable reflection mirrors 4, 5, a lens 7, and fixed reflection mirrors 8, 9. That is, manuscript 3
A movable reflective mirror 4 that moves together with the illumination lamp 6 and a movable reflective mirror 5 that moves in the same direction at half the moving speed of the movable reflective mirror 4.
While keeping the optical path length equal, the light is further subjected to slit exposure through a lens 7 and fixed reflection mirrors 8 and 9, and is imaged onto the drum 1.

The surface of the drum 1 consists of a photoreceptor whose photoreceptor layer is covered with a transparent insulating layer.
It is positively charged by the positive charger 11 which is supplied with a positive high-voltage current. Next, exposure section 1
2, the document 3 on the transparent plate 2 of the document table is illuminated by the illumination lamp 6, and is imaged onto the drum 1 by the movable reflecting mirrors 4, 5 and the fixed reflecting mirrors 8, 9 of the lens 7. At the same time as the photoreceptor is exposed to the original image, it receives an AC discharge from an AC discharger 13 to which AC high voltage current is supplied from a high voltage power supply 10.

Next, the entire surface is exposed by the entire surface exposure lamp 14, and an electrostatic latent image is formed on the surface of the photoreceptor drum, which enters the developing device 15.

Development is performed by powder development using a magnetic sleeve method, and the electrostatic latent image is visualized.

Next, the copy paper 1 sent from the cassette 16
7 is brought into close contact with the drum 1. The transfer charger 18 positively charges the transfer paper using the high voltage power supply 10 and transfers the image on the drum 1 onto the copy paper.

The copy paper after the transfer is separated from the drum 1 by a separating section 19 and guided to a fixing section 20. On the other hand, the remaining toner on the drum surface (photoreceptor) is cleaned by the plate 21 pressed against it, and the next cycle can be repeated again.

Based on the above-described configuration, the feature of the present invention, which allows copying to be easily performed on both the front and back sides of copy paper, will be explained. First, regarding the paper conveyance system, it is constructed so that the copy paper on which front side copying has been completed is guided back to the transfer device for back side copying without being ejected from the machine. That is, the copy paper that passes through the fixing device 20 during front side copying, is conveyed by the ejection roller 22, and advances while having excess charge removed by the static eliminator 23.
The passage of the rear end is detected by the light receiving element 24, and the ejection roller 22 is reversed, leading to the path 2 for back side copying.
5. The guide plate 26 is moved to a position where it guides the copy paper into the path 25 at the same time as the paper ejection roller 22 is reversed, and the copy paper is guided to the back paper feeder and stacked there when making multiple copies.

Next, the copy paper moves to the backside copying process and is transferred to the feed roller 6.
72, and conveyor roller 28
Then, the paper is sent to the transfer device according to the feed signal while being controlled by the register roller 29 again, and after the transfer is completed, it passes through the fixing device 20 and the static eliminator 23, and then is sent to the paper discharge roller 2.
2 to the tray 30.

Next, the operation of the optical system during double-sided copying will be explained with reference to FIGS. 2 and 3.

The document table of this embodiment has a size that covers A3 size, and a case where a double-sided copy of an A4 size book is to be made on A4 size copy paper is taken as an example.

The document placement surface is in the center, A side and B side (each A4
Two A4-sized pages can be placed on the document table at the same time.

First, the case of A-side copying will be explained with reference to FIG. 2. As with ordinary copying paper, the illumination section of the optical system and mirrors 6, 4 have their starting positions immediately in front of the A-side document table, and are controlled by the photosensitive drum. When the exposure process for side A starts and the exposure is completed, the optical system mirror and illumination parts 4 and 6 are activated by the start signal 4a and 6a.
Stop at the position.

At this time, the movable reflection mirror 5 also moves to the position 5a.

Next, the case of side B copying will be explained with reference to FIG. When the exposure process is finished, the optical system
It stops at positions c, 5c, and 6c.

The length of the exposure stroke for side A (same for side B) is the length l of side A plus the slit width and allowance for starting and stopping the movement. Therefore, the optical system is the second
The stop positions 4a, 5a, and 6a shown in the figure are reached.

Therefore, when copying of side A is completed and copying of side B is to be started, it is necessary to move back the optical systems 4, 5, and 6 to match the optical system start positions 4b, 5b, and 6b for copying of side B.

Similarly, when proceeding to A-side copying after completion of B-side copying, the optical system must be aligned with the optical system start positions 4, 5, and 6 shown in FIG.

The feature of this embodiment is that it is easy to copy both the front and back sides of each sheet of copy paper, and it is easy to realize an apparatus that automatically copies the back side after copying the front side.

Next, by determining these sides A and B to be the original platen mounting surface for front-side copying, and the original platen mounting surface for back-side copying, the following convenient features can be added.

The following can be carried out by issuing a signal by utilizing the fact that the original platen start positions for A-side copying and B-side copying are different.

When copying side A First, it is displayed that it is a front copy.

Further, after the copying is completed, an instruction or warning means is provided so that the copy paper is set in the paper feeding state for backside copying.

Alternatively, it may be further automated to set the paper feeding state for back-side copying after copying is completed. In other words, the copy paper that has been copied is not discharged from the discharge roller, but is reversed and placed in the back side copy paper feeding state.

Also, when copying side B, First, it is displayed that it is a reverse side copy.

Furthermore, after copying is completed, an instruction or warning is issued to discharge the copy paper onto the tray, or the copy paper is actively automated and discharged onto the tray.

In this way, it is possible to improve operability by changing the display and operation of the copying machine for A-side copying and B-side copying.

Generally, books are bound on the right side, as shown in Figure 8.
There are two types of left binding, but in both cases, the front side of each sheet of paper is usually an odd numbered page, and the back side is an even numbered page. Therefore, if odd-numbered pages are placed on side A and even-numbered pages are placed on side B, there is no distinction between right binding and left binding, and in either case, error-free double-sided copying becomes possible. In this case, the book is as shown in Figure 8.
Left binding a, b and right binding c, d result in the paper being placed upside down. This is also one of the advantages that by determining sides A and B to be front side copies and back side copies, respectively, convenient instructions can be given for operation.

In addition, if the copying is performed in the order of A-side copying, B-side copying, that is, front-side copying, then back-side copying, in this embodiment, the copied paper is stacked on the tray with the back side facing up, so the pages are It is extremely convenient to have them in order.

Although the present invention has been described above using a copying machine with a stationary document table as an embodiment, it is not limited to this at all.
If it is a copying machine that reciprocates the original, the original platen should be A,
It is sufficient to move the document according to both sides of B, and it is not limited to the transfer method, but also other methods having a document table, for example,
This can be applied to all electrofax type copying machines.

Next, during surface copying, the copying machine passes through the fixing device 20, is conveyed by the ejection roller 22, and is removed from excess charge by the static eliminator 23. The passing of the rear end of the copying machine is detected by the light receiving element 24. , by reversing the discharge roller 22, the passage 25 for backside copying is opened.
A more detailed explanation will be given of the mechanical operation when guided to FIG. 7A and FIG. 7B. First, the fixing device 20 adopts a fixing method using a so-called heat roller, and its configuration includes a heater 45 at the core and a freely rotating heat roller 41.
The surface is covered with silicone rubber. The heating roller 42 is a fixing roller that has a heater 44 at its core and is supplied with heat by a freely rotating pressure roller 43. The transferred copy paper is sandwiched between a heating roller 41 and a fixing roller 42, fixed thereon, and guided to a discharge roller 22.
At this time, a scraper 46 and a separating claw 47 are provided to prevent the fixed copy paper from wrapping around the fixing roller 42 and heating roller 41.

Next, how the discharge roller 22 is rotated forward and reverse will be explained.

First, when the discharge roller 22 is rotating in the direction of arrow A, the electromagnetic clutch 53 is on and the electromagnetic clutch 54 is off, and the chain 50
As a result, the rotation of the sprocket 51, which is free from the discharge roller shaft 57 in the direction of the arrow, is transmitted to the discharge roller shaft 57 via the electromagnetic clutch 53. Next, when the discharge roller 22 reverses in the direction of arrow B, the electromagnetic clutch 53 is turned off and the electromagnetic clutch 5
4 is turned on, and the rotation of the sprocket 52, which rotates in the direction of the arrow by the chain 50, is transmitted to the gear 56 via the electromagnetic clutch 54, and then to the gear 55 fixed to the discharge roller shaft 57, which rotates the discharge roller. 22 rotates in the B direction.

Now, the copy paper that has passed through the fixing device is ejected to the ejection roller 2.
2 and the discharge roller 48 that follows it. A light receiving element 24 and a lamp 49 as a light source are used to pass the trailing edge of the copy paper. When the trailing edge of the paper is electrically detected by the paper trailing edge detection mechanism, the electromagnetic clutch 53, which had been on until now, is turned off by the electrical signal, and the movement of the paper is stopped. By the way, it cannot be said that the transfer paper that has reached the ejection roller section will not be subject to lateral deviation in the direction of movement, so it is necessary to check whether or not there is lateral deviation and to correct the lateral deviation before entering the reverse side copying process. is necessary. To this end, we propose a lateral shift correction mechanism as shown in FIGS. 7A and 7B.

First, as described above, the electromagnetic clutch 53 is turned off and the movement of the paper is stopped for a moment. In FIG. 7B, in order to correct the deviation in the lateral direction with respect to the traveling direction of the paper using the CdS 70 and the lamp 71, first the side edge A of the paper is placed on the optical axis connecting the lamp 71 and the CdS 70 as shown in the figure. You must move the paper in the direction of arrow B until Conversely, if the side edge of the paper is at arrow A' as shown by the dotted line, move the paper in the direction of arrow B' and place the edge on the optical axis connecting CdS 70 and lamp 71. By stopping the movement when the copy arrives, the horizontal deviation of the paper can be corrected.

Next, referring to FIG. 7B, a description will be given of the mechanism for correcting the lateral deviation of the paper.

22 is a discharge roller, and 48 is a discharge driven roller that follows the discharge roller. The driven roller 48 is fixed to a driven roller mounting shaft 72 with a screw, and this mounting shaft 72 is rotatably held by a bearing 73. The bearing 73 is fixed to a discharge roller mounting board 74, and the shaft 72 is positioned by a tension washer 75 so as not to move in the thrust direction. On the other hand, the discharge roller 22 is fixed to a discharge roller shaft 57 with a screw, and the shaft 57 is rotatably fixed to a bearing 76. Also, the shaft 57 is attached to the mounting board 74 in the thrust direction.
and is positioned by a tension washer 77. Further, a pin 77 is driven into the shaft, and the shaft 57 is engaged with an elongated hole C formed in a part of a collar 78 that freely moves in the thrust direction. It is firmly fixed to the shaft 79 with screws or the like. Further, the shaft 79 is fixed to the gear 55 (FIG. 7A). The other end of the shaft 5 is attached to a slide bearing 81 attached to a main body side plate 80 so as to be freely movable in the thrust direction. The mounting board 74 is connected and fixed at the lower part to a part 82a of the slide rail, and this slide rail 82a is connected to the other slide rail 82.
b and is slidably connected by a steel ball 83. The slide rail 82b is fixed to a mounting plate 84, and the mounting plate 84 is fixed to the main body side plates 80 and 85.

On the other hand, a shaft 86 is fixed to the mounting board 74 by caulking or the like, and on the other hand, this shaft 86 is held by a slide bearing 88 attached to a main body side plate 85 so as to be freely slidable. The other end of this shaft 86 is threaded. On the other hand, a collar 89 having a female threaded portion that engages with the threaded portion of the shaft 86 is fixed at one end to the shaft of the reversible motor 90 . The reversible motor 90 is fixed to a motor mounting plate 91, and the motor mounting plate 91 is fixed to a substrate 92 attached to the main body side plate 85. Here, when the collar 89 rotates in the direction of arrow D, the shaft 86 moves in the direction of arrow E.

Further, the lamp 71, the CdS 70, and a slit 93 for narrowing the optical axis in order to accurately stop the side edge of the paper at a specified position are fixed to the main body side plate 85 with a mounting plate or the like.

On the other hand, regarding the CdS 24 and the lamp 49, there is still a slit 94 to narrow down the optical axis.
The lamp 49 and the CdS 24 are fixed to the main body side plate 80 with a mounting plate or the like, and the slit 94 is fixed to the mounting board 74.

Next, the operation of this correction mechanism will be explained.
When the paper stops advancing with the side edge of the paper at A in FIG. 7B, CdS 70 and lamp 71
Due to the function of the paper side edge detection mechanism (described later), the reversible motor 90 rotates its collar 89 in the direction D until the moment the side edge of the paper crosses the optical axis of the lamp 71 and CdS 70. It works,
The shaft 86 is moved in the direction of arrow E, and the moment the side edge of the paper crosses the optical axis, the motor instantly stops its operation.

On the other hand, if the paper is at the dotted line position in Figure 7B,
That is, when stopped at the position of arrow A' (i.e., crossing the optical axis of lamp 71 and CdS 70), the light from lamp 71 and CdS 70 is detected by the paper side edge detection mechanism using CdS 70 and lamp 71. Until the moment when the side edge of the paper crosses the axis, the collar 89 rotates in the opposite direction to the rotation direction D, the shaft 86 moves in the opposite direction to the arrow E, and the side edge of the paper crosses the optical axis. The moment the motor stops operating, it immediately stops operating.

As described above, when the side edge of the paper reaches its normal position, the electromagnetic clutch 54, which had been off until now, turns on, and the ejection roller that grips the rear edge of the copy paper rotates in the opposite direction. At the same time, the swing lever 61 is normally pulled by the spring 60, and accordingly, the guide plate 26 (which is fixed to the shaft 62 and to which the swing lever 61 is fixed) also moves as shown in FIG. The state is maintained as shown by the solid line shown. The guide plate 26 is displaced around the shaft 62 to the position shown by the dotted line in FIG. 1 by the operation of the solenoid 58.
The copy paper is guided into a path 25 for backside copying and stopped near a register roller 29 by transport rollers 27, 28.

After the paper has completely passed through the ejection roller section, the reversible motor will, for example, first remove the paper until the light from the lamp 49 hits the CdS 24, in other words, until the slit 94 returns to its normal position (the position shown in FIG. 7B). In order to detect the side edge, the mounting board 74 moves in the opposite direction to the direction in which it is moved (EXE direction) and stops the moment the light from the lamp 49 is detected by the CdS 24.

As mentioned above, correcting the horizontal misalignment of the paper is to correct the original image on the copy paper.
This will help prevent lateral slippage.

Next, copying operations when using this copying machine will be explained in detail with reference to FIGS. 4 and 5.

40 is a main switch that enables the copying machine to be used.

Reference numeral 31 is a copy number setting dial which allows setting of 1 to 99 copies by aligning the scale of the dial with the index, and 32 is a copy number display tube that indicates the number of copies that have been made. Reference numeral 34 is a copy start button for copying multiple copies, and if you wish to copy only one copy, press another copy start button 35 to copy only one copy regardless of the instruction on the number of copies set dial 31. . Reference numeral 36 is a shading selection dial that determines the darkness or lightness of the image, and 37 is a selection dial for copy types such as A-side, B-side, single-sided, and double-sided (AB). Here, "for side A" means that when this dial 37 is set to A, indicator lamp A lights up and only side A of the document table is copied, and the copy paper is not ejected to the output tray but as shown in FIG. 7A. After the trailing edge of the copy paper is detected by the light receiving element 24, the solenoid 5
8, and is guided by the action of electromagnetic clutches 53 and 54 to stop at the paper feeding device for copying the B side. Further, when making multiple copies, the copy sheets are guided to a path for back side copying, and a predetermined number of the copy sheets are stacked on a paper feeding device for B side copying.

Next, when the dial 37 is set to B, the indicator lamp B lights up and only the B side of the document table is copied. Regardless of whether it is a multiple copy or a single copy, the B side copy paper feed device is used. While there is copy paper on which side A copying has been completed, copy paper is supplied from there,
If there is no copy paper, the copy paper is supplied from the cassette 16, but after copying is completed, the copy paper is discharged to the paper discharge tray 30. If the dial 37 is set for one side, neither indicator lamps A nor B will light up. As with conventional copying machines, copies up to A3 size can be made on one side of the copy paper, and the copy paper with copies made on one side is ejected to the paper ejection tray 30 as is.

Next, when the dial 37 is set for AB and the number of sheets set dial is set to a predetermined number of sheets, the A-side copying process is repeated for the predetermined number of sheets, and each copy sheet that has been copied on the A-side is guided to the path for back-side copying. , a predetermined number of copy sheets are loaded into the paper feeding device for copying side B, and when the process of copying the predetermined number of sheets of side A is completed, the process of copying side B automatically begins, and the process of copying the predetermined number of copies of side B is completed. After repeating this process, the copy paper that has been copied on the B side is discharged to the paper discharge tray.

This operating method provides various conveniences regarding double-sided copying. For example, when copying both the front and back sides of a document, such as the pages of a general book, there are cases where the front and back sides cannot be placed on their respective document placement surfaces at the same time.

Even in this case, when you open a book and place it on the manuscript table, such as when copying several consecutive pages of a book, and each opened page is placed on its own manuscript placement surface, first turn the selection dial 37. Copy the original on side B onto the back side of the first sheet of copy paper and eject it, then set the selection dial 37 to side A and copy the original on side A on the front side of the second copy sheet. Copy.

Turn over one page of the book, use dial 37 for side B, copy onto the back of the second copy paper, then use dial 37 for side A, copy onto the front of the third copy paper, and turn the book again. Then, use the dial 37 for side B to copy onto the back of the third sheet of copy paper, then use the dial 37 for side A to copy onto the front of the fourth sheet of copy paper, and so on. The placed two-sided originals are not copied onto both sides of the same copy paper, but are copied onto one side of the first copy paper and the other side of the second copy paper. However, even in this case, the two sides to be copied are placed on the document table at the same time.

Also, in this case, it is necessary to set the manuscript surface so that the odd numbered pages of the book are on side A and the even numbered pages of the book are on side B, as mentioned above, to save operational effort. It is.

Also, to determine whether sides A and B are being copied to either page of the book on the manuscript table, the specimen lamp should be near side A.
Since they are lit near the B side as 39 for the A side and 38 for the B side, they can be easily distinguished.

Next, if the two sides of the original can be separated and placed on sides A and B on the document table at the same time, and you want to copy them onto both sides of a single sheet of copy paper, you can perform double-sided copying as follows. .

First, set the number of copies you need using the number set dial 3.
1, then turn the selection dial 37 to AB.
When the user presses the copy start button 34 for convenience, the required number of double-sided copies can be automatically made. At this time,
Since both indicator lamps 39 and 38 of both A and B are lit, it can be confirmed that double-sided copying is being performed automatically. As described above, one of the features of this copying apparatus is that it can perform double-sided copying without any operational complexity in any case where double-sided copying occurs.

Here, a detailed explanation will be given of the paper feeding device for back side copying and the means for separating the copy sheets stacked thereon one by one and feeding them into the back side copying process. In Figures 1, 9, 10, and 11, 670 is an upper guide plate that guides the copy paper 681 entering the reverse side copying process, and 671 is a paper feed plate on which the sent copy paper can be stacked. be.

672 and 673 are separation/feed rerollers that rotate in opposite directions (rotation directions are as shown in the figure), and the back side copy paper 681' placed at the top is conveyed by the conveyor roller 2.
8 and register rollers 29.

Also, as can be seen in the embodiment shown in FIG. 1, if the paper feed plate 671 is inclined forward and downward with respect to the copy paper traveling direction, the leading edge of the copy paper will be closer to the separation/feed roller 6.
72,673. In addition, as a means for actively performing the alignment action, the method shown in FIGS.
It is effective to use a swinging arm as shown in FIGS. To explain the swinging arm in detail, in FIGS. 1 and 9, reference numeral 675 is the swinging arm, which normally does not protrude above the paper feed plate 671 as shown by the two-dot chain line, so that the copy paper is not placed on the paper feed plate 671. Even if it comes in, it will not be an obstacle.

Next, when the backside copying process begins, this swinging arm swings about the shaft 676, causing the paper feed plate 6
The copy paper on the copy paper 71 is easily pushed and aligned with respect to the separating/feeding roller, thereby facilitating smooth paper feeding. (Here, a boss 677 is fixed to the swing arm 675, and the boss 677 is attached to the shaft 677 with a screw etc.
8, and the shaft 678 is rotatable. ) Also, as a means for arranging copy paper, see Figure 12, Figure 1.
As shown in FIG. 3, means may be taken in which the copy paper is intermittently squeezed by rotating a roller (or a cam-shaped member) eccentrically attached to a shaft 680.

Also, in order to arrange the paper, the paper feed plate 671 is placed on the ninth
As shown in section F of FIG. The front end of the copy paper is guided while being in contact with this screen, and is fed in as shown in b and c, and is arranged so as not to interfere with paper feeding when entering the next backside copying process.

Also, the separation/feeding rollers 672 and 673 are the first
As shown in Figure 0, they are not in contact with each other and have a slight gap. Therefore, when the back side copy paper is sent to the separation/feeding roller in the A side copying process, by rotating the roller 673 in the direction of the arrow shown in FIG. , 673, they move back to a place where the action of the rollers 673 cannot reach and are placed one after another, and here too they are subjected to the placing action. In this way, the copy paper is fully prepared before entering the reverse side process.

Furthermore, in the example shown in FIG. 14, instead of the separating/feeding roller 673 as shown in FIGS. 1, 12, and 13, a fixed member is installed to form an appropriate gap with the separating/feeding roller 672. This fixing member has an appropriate coefficient of friction, and a plurality of fixing members may be installed. By using the fixing member, copy paper for the back side is also stacked on the paper feed plate 671 in the A side copying process,
In the next backside copying process, the backside copy sheets are separated one by one and sent to the next conveyance roller 28 and register roller 29.

The present invention provides first and second paper feeding devices and a document platen A.
Although the description has been made in relation to side and B side, it goes without saying that the present invention can be similarly applied to conventional copying machines that do not distinguish between front side copying and back side copying with respect to the document placement surface. At this time, it is possible to copy the front and back sides while replacing the original.

Next, the electrical control method according to the present invention will be explained using the above embodiments. FIG. 15 is a block diagram in which devices related to control are divided by function. first,
101 is a home position set of the drum when the power is turned on, safety devices such as a power input section, a door switch, a shut-off in case of a jam, etc.;
It also includes various reset devices such as those for resetting the control circuit, which will be explained later, and a warm-up setting device if necessary. Next, reference numeral 103 is a device for checking the filling and replenishment of cassettes, transfer paper, developer, and other consumables, similar to the conventional device. Further, 105 includes a copy selection dial, a copy number setting dial, a copy start button, and a copy stop button. Signals from these two parts are input to the central control unit section (hereinafter referred to as CPU) of 107, which generates operation command signals to various operation sections for copying.
7 can be further divided into the following five parts. First, 109 is a part that selectively commands various copying operations set by 105, which includes a drum copy rotation command. Further, reference numeral 111 is a part that generates a transport rotation command signal that is further required after the developing process of copying. Next, 113 is a part that generates commands to move the optical system, that is, forward, backward, and stop, 115 is a part that generates a command signal to set the copy paper in the preparation position for backside copying, and 117 is the part that generates the preparation position or Normally, it is a device that feeds copy paper from a cassette to a copying position. As described above, the CPU 107 issues operation command signals to each operation execution section. Reference numeral 121 includes operation execution sections that do not require feedback to the CPU 107, such as a document irradiation lamp, a high-voltage power supply operation section, etc., as in a conventional copying machine. Reference numeral 123 denotes a drum rotation operation unit, which includes a drum rotation position detection device at a necessary position, and its signal is
Feedback is provided to the CPU 107. 12 more
5 is an optical system movement unit which similarly includes a position detection device and receives feedback from the CPU 107. Reference numeral 127 denotes a copy paper detection device, which is provided at a necessary location in the copy paper circuit and generates a paper detection signal.
7 is input.

Next, 131 is a jam detection device, which is used to confirm the normal conveyance of the transfer paper, and is the same as that in conventional devices. Reference numeral 129 denotes various display devices, which are parts that control necessary display on the panel surface.

Although the configuration has been briefly explained above, parts related to the present invention will be explained in more detail below with reference to the drawings.

First, in Figure 16a, 135, 136, 1
Reference numerals 37, 138, and 139 indicate position detection devices for the optical system 4, which are composed of microswitches, but other object detection devices such as photodetectors may be used in addition to this example.
Here, 135 is also the home position (start position) for single-sided copying or A-side copying.
It also means the position, and 136 also means the start position when copying the B side. Next, 138 also means the back position for single-sided half-size copying and A-side copying, and 139 also means the back position for single-sided full-size copying and B-side copying. Therefore, in the case of a single-sided half-size copy, the optical system 4 advances from the position of the position detector 135 to the position 138, and in the case of a single-sided full-size copy, the optical system 4 moves forward from the position of the position detector 135 to the position 138.
Move forward from position 35 to position 139. Further, in the case of A-side copying, it is exactly the same as single-sided half-size copying, and in the case of B-side copying, it advances from position 136 to 139. Here, this example is shown in half size.
For A4 size and full size A3 size, the positional relationship of each position detection device may be as follows in order to effectively implement the present invention. That is, in Fig. 10, the part corresponding to l ₁ and the part corresponding to l ₂ are A4
Match the width of the plate size. Therefore, l ₃ , which is the sum of l ₁ and l ₂ , corresponds to the vertical width of the A3 version. Assuming that the original is placed at the position of the length shown in each of these, the movement range of the optical system that irradiates it and derives the optical image signal reflected on the original image is determined in each case.
It is most convenient to move with a little extra length than l ₁ , l ₂ , and l ₃ . That is, the start position 135 or 136 is spaced by α ₁ or α ₃ from the left end of l ₁ (or _{l 3} ), respectively, and the back position 138 or 139 is spaced from the left end of l ₁ (or l ₃ ) or
It is better to have a distance margin of α ₂ and α ₄ from the right end of l ₃ ). Therefore, in this case, the start position 136 and the back position 138 are located apart from the center position 140 by α ₃ and α ₂ to the left and right, respectively.

Next, a signal generating device for counting the number of copies may be provided as an optical system position detecting device at the position shown at 137 in FIG. 16a. Conventionally, this type of signal uses a paper feed command signal to be described later, a paper detection signal in a copy paper path, or a signal from another optical system position detection means or a drum rotation position detection device. . In this embodiment, an optical system position detecting means located between 136 and 138 is provided to detect this signal, and the signal from there is used as a copy count signal to explain the subsequent operation. By combining this signal and the optical system advance execution signal, both signals are generated at the same time in the process when copying one-sided half-size, one-sided full-size, side A, and side B. This is done only once and is convenient for subsequent operations.

Furthermore, in FIG. 1, reference numerals 24, 133, and 134 indicate paper passage detection means, which can be composed of a lamp-photosensitive element bear or an ultrasonic transmitter/receiver bear, but in this embodiment, in order to avoid complication of explanation, this detection is simply used. The following explanation will be made assuming that the signal from the section is at a high level when paper is being detected and is at a low level when no paper is passing through. Further, the positions of these paper passage detecting sections and the roles of the signals from them in the sequence will be explained when the paper feeding operation and the preparation position setting operation are explained.

Next, this circuit is a control circuit constructed mainly using digital binary logic circuits. First, in order to simplify the following explanation, the digital logic symbols and some circuit units used in this circuit example will be explained in advance. First, Figure 17-a Figure 5
10 is a positive AND gate, input terminal 51
1,512 has two terminals, or 513 and later models have three or more terminals, and those with two input terminals, both or three or more, have all terminals at high level, that is, logic 1 (hereinafter simply written as 1). When this happens, the output terminal 214 becomes 1, and if there is even one low level, that is, logic 0 (hereinafter simply written as 0), the output terminal 514 becomes 0. Next, Figure 17-b 5
16 is an inverter; if the input terminal 517 is 1, the output terminal 518 is 0; if 517 is 0, the output terminal 518 is 1. In addition, in FIG. 11-c, the positive tape OR gate has input terminals 521,
If there are two input terminals 522 or three or more input terminals after 523 and at least one of these input terminals is 1, the output terminal 524 becomes 1. Also, FIG. 17-d shows a preset counter 500, and the overall function of this circuit is that the data signal from the preset dial for the number of copies is input to the PD input terminal 526.
The data number is set in the internal counter by adding the preset command signal as 1 from the PRS input terminal 528. Also
CP terminal 527 is a clock input terminal, and when a pulse is applied from this terminal, the output of the internal counter is the set data from terminal 526 minus the number of pulses. Q terminal 531 is
This is a terminal that outputs 0 when the output of the internal counter becomes 0, and the R terminal 529 is a reset input terminal, and when 1 is added from this terminal, both the set input and Q output of the internal counter are reset to 0. Further, the DIS terminal 530 is an output terminal for displaying the counter output. This preset counter 502
The overall functionality of is used in the circuit of the present invention as described above. In order to satisfy this overall function, in addition to the above-mentioned counter circuit, a 0 detection circuit and an encoder for converting a decimal signal into a binary signal are included internally, but these are not directly related to the present invention. Since there is no such thing, detailed explanation will be omitted. Next, FIG. 17-e shows a flip-flop circuit 533, which is a D-type edge-triggered flip-flop used in the embodiment of the present invention, but is not limited to this. The function of this D-type edge-triggered flip-flop (hereinafter simply referred to as FF) is that when a change from 0 to 1 is applied to the CP terminal 536 at the terminal 536, the current D Data of 1 or 0 at input terminal 535 is output and held. Further, the R input terminal 534 is a reset input terminal, and sets the output of the output terminal 538 to 0 regardless of the D and CP input terminals. Also, S input terminal 5
37 similarly makes the output terminal 538 1.
Here, the R and S input terminals generally exhibit their functions when they are set to 0, but in order to simplify the explanation hereinafter, they will be explained assuming that they function when they are set to 1. Further, the Q terminal 539 outputs a level opposite to that of the output terminal 538.

Each circuit using each of the above logic elements will be described in detail.

First, the control circuit corresponding to the copy selection section is
It is shown in Figure 8. In Fig. 18, the copy selection signals from the operation panel are: single-sided copy (hereinafter referred to as S copy), double-sided A copy (hereinafter referred to as A copy), double-sided B copy (hereinafter referred to as B copy), and double-sided automatic copy (hereinafter referred to as B copy). If each signal of (hereinafter referred to as AB copy) is terminal 149, 151, 153, 1
It is input as 1 from 55. In addition, if a half-size cassette signal (hereinafter referred to as HSCP) or a full-size cassette signal (hereinafter referred to as FSCP) is used as a signal for the loaded paper cassette, terminal 1
Entered as 1 from 45,147. Furthermore, the signal when the copy button is pressed (hereinafter written as CCP)
The signal when the copy stop button is pressed (see below)
CSP) and the copy number data signal (hereinafter referred to as MCD) set by the multi-copy dial are sent from terminals 159, 157, and 161, respectively.
They are input as 1 except for MCD, and MCD is input as a predetermined input group. Also, when there is paper in the cassette or in the stock section, the signal becomes 1 (hereinafter referred to as PDPE and PDPC), respectively, at terminal 150,
148. Further, from the terminal 163, the optical system is connected to the position detection device 137 in FIG. 16-a.
A copy count clock pulse signal (hereinafter referred to as CCCP) that generates 1 when passing the position of is input. Further, from the terminal 166, an A copy execution signal (hereinafter referred to as ACPL), which will also be described later, is inputted as 1 during execution of the A copy. First of all, the preset counter (hereinafter referred to as PSCNT) 20
When CCP is applied as 1 from the normal terminal 159 to the PRS terminal of 2 through the two-input OR gate 191, the MCD data applied from the terminal 161 to the PD terminal of PSCNT is stored inside the PSCNT circuit 202, and further At this time, the Q output terminal becomes 1, and this signal generates each command signal for B copy, A copy, full size S (single-sided) copy (hereinafter referred to as F copy), and half size S copy (hereinafter referred to as H copy). A and the second condition is that the copy paper or cassette loading signal is
7, 198, and 199, but first the output is a half-size copy command signal (hereinafter referred to as
A PDPE signal and an HSCP signal are applied to the input terminal of a gate 199 (written as HCCP). Next, the PDPE signal and the FSCP signal are applied to the input terminal of a gate 198 whose output is a full-size copy command signal (hereinafter referred to as FCCP), and the gate whose output is a double-sided A copy command signal (hereinafter referred to as ACCP). A PDPE signal and an HSCP signal are applied to the input terminal of 197. Furthermore, this second condition is applied to the output of the gate 196 whose output is a double-sided B copy command signal (hereinafter referred to as BCCP), so that it is determined whether there is copy paper in the half-size cassette or in the stock section. In order to satisfy this condition, first the PDPE signal and HSCP signal should be connected by two-input AND
is applied to each input terminal of gate 200, and gate 2
00 output and PDPC signal are two input OR gate 19
5 can be made in addition to gate 196.

Next, as a third condition, the signal from the copy selection dial (FIG. 5, 37) is
It is added to 97, 198, 199,
First, the S signal is applied to gates 199 and 198. Further, the A signal is applied to the input terminal of the gate 197 via the two-input OR gate 182, and the B signal is applied to the input terminal of the gate 196 via the two-input OR gate 185. In the case of copying, this third condition is AB
The AB copy selection signals that must be made during automatic copying are also provided by two-input AND gates 18.
OR gate 182, 18 as the output of 1,184
Gates 197, 196 through other input terminals of 5
However, in the sequence, AB
When copying, when the copy button is pressed, A
After copying is performed for the set number of sheets, B copy is executed again for the set number of sheets and ends. In order to perform this control, first, by applying the inverted signal via the BCCP inverter 192 and the CCP signal to each input terminal of the two-input AND gate 193, it is possible to detect that there is no B copy command (0) and the copy button is pressed. When the output of the gate 193 becomes 1, the FF203
At this time, the Q terminal of the FF 203 becomes 1. This Q output signal is added to the gate 181 as 1 and the other input terminal of the gate 181 is AB
Since the copy signal is added, gate 181
The output of is 1, which satisfies the third condition for A copy. Also, in the case of the final A copy, the Q of PSCNT
Even if the output terminal becomes 0 and ACCP becomes 0, the ACPL signal (A copy execution signal) does not become 0 yet, as will be described later, and at this time, the three-input AND gate 18
By adding the AB copy signal, the ACPL signal, and the inverted signal from ACCP inverter 187 to each input terminal of 6, the output becomes 1, which is applied to one input terminal of 190 of the two-input AND gate. CCCP is applied as 1 to the other input terminal via the two-input AND gate 194 during forward movement, that is, when OFL is 1. When the output of gate 186 is still 0 and is applied as 1 to one input terminal of two-input AND gate 188 via inverter 189, the output of gate 194 is applied to PSCNT via the other input terminal of gate 188. It is applied to the CP pin as a clock pulse. Therefore,
In the case of copies other than AB copy, the output of gate 188 is directly counted by PSCNT 202, but during AB copy, the output of gate 194 becomes 1 during the execution of the last A copy, and gate 188
Q is applied to the CP terminal of PSCNT202 via
When the output becomes 0, the output of the gate 197 becomes 0 as described above, and when the ACCP becomes 0, the gate 186
The output of gate 188 becomes 1, that is,
The signal applied to the CP terminal of PSCNT becomes 0,
Further, the output of the gate 190 becomes 1 and is applied as 1 to the PRS terminal of the PSCNT 202 via the OR gate 191, and the PSCNT 202 is set again and the Q output terminal becomes 1. At this time, the output of the gate 190 is further applied to the R terminal of the FF 203 and the Q output becomes 0, so the Q output of this FF 203 is inverted via the inverter 183 and becomes 1, and is added to one input terminal of the gate 184. Rare gate 18
The output of gate 181 is 1, and conversely, the output of gate 181 is 0.
Therefore, at this time, the third condition at gate 196 is satisfied, BCCP becomes 1, and ACCP does not become 1 this time. Therefore, the AB automatic copying is completed after further B copying is performed for the set number of copies.
Incidentally, in the PSCNT 202, the set number of sheets data is inputted from the terminal 161. The data given by the MCD signal and output from the DIS pin is PSCNT
A signal that indicates the number of clock pulses applied from the CP terminal after 202 is set by the signal applied to the PRS terminal, that is, the number of copies to be executed.
A terminal 175 is output as DISP to a display section (not detailed).

With the above process, terminals 173, 163, 17
Double-sided B copy command signal from 1,169 respectively
BCCP, double-sided A copy command signal ACCP, single-sided full-size copy command signal FCCP single-sided half-size copy command signal HCCP are output. Next, the steps of generating each copy execution signal and transport rotation signal will be explained with reference to FIG. 16b and FIG. 19. First, in FIG. 16b, 402 is a photosensitive drum, 401 is a micro switch for detecting the rotational position of the drum, and 40
3a, 403b, 404a, and 404b are cams that drive the microswitch 401, and are shown around the drum 402 for convenience, and an arrow 405 indicates the rotation direction. Here, when each cam reaches the actuator section of the microswitch 401 and drives the microswitch, a signal of 1 is generated by a pulse generation circuit (not shown) and applied to the control circuit. In this embodiment, the signal 1 generated by the cam 403a is the normal stop position of the photosensitive drum. This signal will be written as DHPA below. Further, 403b is used for detecting the rotational position of the photosensitive drum.
404a and 404b are provided, but the cam 403b
is located at a position rotated by 180 degrees from the cam 403a, and is provided to improve the time efficiency of half-size copying, and the 1 signal generated by the cam 403b, the details of which will be described later, will be hereinafter referred to as DHPB. Further, the cams 404a and 404b serve as timing pulses for the generation of each copy execution signal as will be described later by DHPA and DHPB, and generate a timing signal for starting the forward movement of the optical system after a certain period of time delay from the time when the copy execution signal is issued. , respectively below.
Write OSPA, OSPB. In addition, micro switch 4
02 may be a plurality of units corresponding to each cam in order to separate each signal, and in the following explanation, the DHPA, DHPB, OSPA,
OSPB is performed assuming that the signal lines have already been separated. In FIG. 19, first, terminals 169, 17
HCCP from 1,167,173 respectively,
FCCP, ACCP, BCCP signals are input, and FF
It is added to each D terminal of 228, 224, 225, and 226.

Each copy command signal is further provided by a 4-input OR gate 21
The output of gate 219 applied to each input terminal of 9 is first directly applied to one input terminal of two-input AND gate 217, and the output of gate 219 is applied to each input terminal of inverter 214,
It is also applied to the other inverted and delayed input terminal via 215 and 216. Therefore, when any copy command signal is generated and the output of gate 219 becomes 1, the output of gate 217 becomes inverter 2.
14, 215, 216 for the signal delay time and becomes 1 through the inverter 218.
added to one input terminal of the AND gate 223,
The other input terminal is connected to the DHPA from terminal 210.
signal is added, and the output of gate 223 is FF
It is added to each CP terminal of 228, 224, 225, and 226. Therefore, when the copy command signal is already 1, the four flip-flops are
DHPA is used as a clock, and when DHPA becomes 1 and the drum is in a stopped state, a clock pulse is generated with a delay of the aforementioned delay time from the rise of the copy command signal, and the Q output terminal becomes 1. At this time, in response to the generation of each copy command signal of HCCP, FCCP, ACCP, and BCCP, FF2
The Q outputs of 28, 224, 225, and 226 become 1, and the terminals 236, 231, 166, and 234 respectively.
to single-sided half-size, single-sided full-size, double-sided A, double-sided B copy execution signal (respectively
(written as HCPL, FCPL, ACPL, BCPL). These copy signals become 0 due to the DHPA generated after the corresponding copy command signal becomes 0. Also HCPL, FCPL, ACPL,
When the BCPL is further applied to each input terminal of the four-input OR gate 230, the output becomes a signal (hereinafter referred to as CPL) indicating the presence of any copy execution signal, and is output from the terminal 232 to the subsequent circuit. In addition, the output of the inverter 214 and the two-input OR gate 222
The output of is applied to each input terminal of the two-input AND gate 221, the output is applied to the D terminal of FF 227, the DHPA signal is applied to the CP terminal of FF 227, and the terminal is applied to each input terminal of gate 222. 213 to the transfer paper ejection roller (Fig. 1
2) Paper detection signal A (PDPA) located in the section and FF
By adding the output signal of 227,
When DHPA becomes 1, the Q output of FF227 is 0 without any copy command signal, that is, the output is 1, or the Q output of FF227 is 1 when the transfer paper is still being ejected. Then, the drum continues to rotate, the drum rotates once, and DHPA is activated again.
If the ejection of the transfer paper has been completed when this occurs, the value returns to 0. In other words, when the paper passes through and PDPA becomes 0,
Q of FF227 becomes 0 due to DHPA and stops.
Therefore, since the drum is stopped after confirming discharge, it is possible to prevent paper from remaining in the machine. This FF227 Q
The output is output from the terminal 235 as a transport rotation signal (hereinafter referred to as FFIL). In addition, the CPL and FIL signals are added to each input terminal of the two-input OR gate 229, and the output is output from the terminal 23 as a drum rotation signal.
3, but a circuit (not shown) prevents the drum from stopping at any position other than the position where DHPA is generated. Then the 16th
In Figure a and Figure 20, the optical system advance signal (hereinafter
(written as OFL) and backward signal (hereinafter written as OBL)
The generation process will be explained. First, in FIG. 10a, a signal that generates 1 at position 135, ie, optical system home position A (hereinafter referred to as OHPA), a signal that generates 1 at position 136, ie, optical system home position B (hereinafter referred to as OHPB), and position 1
Signals that generate 1 at 38 and 139, that is, the optical system home positions A and B (hereinafter referred to as 1, respectively)
(written as OBPA and OBPB) are input from terminals 211, 212, 267, and 268 in FIG. 14, respectively. Here, first, the Q output of FF281 is connected to terminal 16.
5 as DFL, and the output is output as OBL from terminal 290 via two-input AND gate 284, that is, satisfying another condition.
OHPB to each input terminal of AND gate 285,
BCCP, the output of gate 285, and OHPA are applied to each input terminal of a two-input OR gate 282, and the output of gate 282 is applied via inverter 283 to the other input terminal of gate 284. Therefore, the output of FF281 is 1
In other words, when the optical system is not moving forward, the optical system is at home position A, or in the case of double-sided B copying, the optical system is stopped even if it is at home position B. At this time, the output of the gate 284 becomes 1 and the optical system retreats.

Here, the OHPA signal is applied to the D terminal of FF281 via the two-input OR gate 278, and
OHPB, BCPL signal is two input AND gate 274
The output of the gate 274 and the output of the FF 281 are applied to the respective input terminals of the two-input AND gate 275.
The output of 75 is also applied to the D terminal of FF 281 via the other input terminal of gate 278, i.e.
If OHPA is 1 or B copy
If OHPB is 1 and not moving forward (OFL is 0)
Even if , 1 is added to the D terminal. At this time,
If CPL is 1, this is a two-input AND gate 28
Since it is applied to one input terminal of 0, the above
OSPA is connected to the FF281 via the three-input OR gate 279 and the other input terminal of the gate 280.
At this time, the Q output becomes 1 and the optical system moves forward. In addition, when half-size copying and double-sided B copying are performed continuously, in order to increase time efficiency, the OSPB that occurs when the drum rotates 180 degrees at the drum rotation position is also used to start the forward movement and start the copying process. can be executed. This means that the HCPL and BCPL signals are passed through a two-input OR gate 276 to a two-input AND gate 2.
In addition to one input terminal of gate 277, when the output of gate 276 is 1, OSPB is input through the other input terminal of gate 277 and further through gates 279 and 280.
It is added to the CP terminal of FF281 and the optical system can move forward again. In the case of double-sided B copying, after the optical system starts moving forward from home position A, it reaches optical system home position B, and the OHPB
becomes 1, the output of gate 274 becomes 1, and is applied to the CP terminal of FF 281 via gates 279 and 280. At this time, since the output terminal is 0, the output of gate 275 becomes 0, and therefore, ,
Since 0 is added to the D terminal of FF281, the Q output becomes 0 and forward movement stops, and at the same time the output of gate 275 becomes 1 again and gate 27
1 is again added to the D terminal via 8, and the optical system starts moving forward again due to the next generated OSPA or OSPB. That is, the optical system advancement timing can be synchronized with the rotational position of the photosensitive drum.
Next, the optical system is reversed (starting backward) as follows. First, HCPL and ACPL are applied to each input terminal of the two-input OR gate 271, and the gate 271
The output of gate 272 and OBPA are applied to each input terminal of the two-input AND gate 272, so in the case of half-size copying and double-sided A copying, when OBPA occurs, the output of gate 272 becomes 1 and the two-input OR
It is applied to the R terminal of the FF 281 via the gate 273, the Q output becomes 0, and the output becomes 1, stopping forward movement and at the same time starting backward movement. Also,
OBPB for full size copy and double-sided B copy
When becomes 1, FF281 is passed through gate 273.
1 is added to the R terminal of , and the optical system is inverted.

Next, FIG. 21 shows a transfer paper feed control circuit.
As mentioned above, in this embodiment, the timing of paper feeding is synchronized with the start of movement of the optical system, that is, when the optical system advances a certain distance from the home position. The signal from the position detection device that is now located a certain distance away from the optical system home position A is defined as a paper feed start pulse A (hereinafter referred to as PFSA). The signal from the position detection device existing at the position is used as paper feed start pulse B (hereinafter referred to as PFSB), and the position detection device generates a signal of 1 only while the optical system passes that position. Same as description. Furthermore, as mentioned above, in the case of B copying, transfer paper must be fed from the stock section shown in FIG. A signal (hereinafter referred to as PDPC) determines whether or not paper can be fed. Even if this PDPC is 0, if a half-size cassette is installed and there is transfer paper in it, paper will be fed from the cassette. Figure 21 shows that PFSA and OFL
and an inverted signal via the BCPL inverter 307 is applied to each input terminal of the three-input AND gate 305, so if PFSA becomes 1 while the optical system is moving forward during a copy other than B copy, the output of the gate 305 becomes 1. It is output from a terminal 312 via a two-input OR gate 311 as a signal (PFCC) instructing paper feeding from a cassette. Also, PFSB and
When OFL and BCPL are applied to each input terminal of the three-input AND gate 306, when the B copy optical system advances and PFSB becomes 1, the output of the gate 306 becomes 1, but if PDPC is 1 at this time, the gate Since the output of 306 and the PDPC signal are applied to each input terminal of the two-input AND gate 310, the output of the gate 310 becomes 1 and is output from the terminal 313 as a paper feed command signal (PFCP) from the stock section. . In addition, the gate 306 and the PDPC inverter 3 are connected to each input terminal of the two-input AND gate 308.
Since the signal via 09 is applied, when PDPC is 0, the output of gate 308 becomes 1, and the other input terminal of gate 311 becomes a command to feed paper from the cassette. Therefore, only B and AB copies of half-size paper can be copied in succession.

Next, in the case of double-sided A copying, the process control circuit that transports the paper that has been transferred to the stock section is shown in Figure 1.
This will be explained using FIGS. 22 and 23. First, in FIG. 22, the ACPL and OBPA signals input from terminals 166 and 268, respectively, are applied to each input terminal of a two-input AND gate 321.
1 output is connected to the S terminal of FF322, and
It is also added to the CP terminal of FF322, and the D terminal is shorted to ground and is always 0, so
When OBPA becomes 1, the Q output of FF322 becomes 0, but at this time, if double-sided A copy is being performed, gate 3
The output of 21 also becomes 1, and the Q output becomes 1 again.
Further, the Q output of the FF 326 becomes a high speed preparation position set command (hereinafter referred to as HPFC) together with a timer circuit to be described later, but at this time it becomes 0 and the output terminal becomes 1. Q output of this FF326 and FF3
26 are applied to each input terminal of a two-input AND gate 323, and the output of the gate 323 becomes 1 and is applied to the D terminal of the FF 324. Now number 1
When the signal from the paper detection device A24 (hereinafter referred to as PDPA) located at the paper ejection roller 22 in the figure rises to 1 by detecting paper, this signal is applied from the terminal 213 to the CP terminal of the FF 324, and D The terminal signal is output from the Q terminal, but in the case of A copy, by the time OBPA becomes 1, the previously copied transfer paper has already been ejected and PDPA has become 0, or the leading edge of the transfer paper is Since the paper has already passed through the paper detection device A24 and PDPA has already become 1, the Q output of FF322 is 1 again as described above.
After that, PDPA rises to 1 when the transfer paper of the copy made by the movement of the optical system at this time passes the paper detection device A24. As mentioned above, after the D terminal of FF324 becomes 1, PDPA
is connected from terminal 268 to the CP terminal of FF324.
When PDPA rises to 1, the Q output becomes 1, and this output is applied to the D terminal of the FF326. FF32
The PDPA signal is connected to the inverter 325 at the CP terminal of 6.
Since it is added via FF324, if PDPA rises to 0 after the output of FF324 becomes 1, FF3
The Q output of 26 becomes 1. This Q output is further outputted from the terminal 328 via a timer means (details omitted) DT (hereinafter simply referred to as DT), so that the Q output of the FF 326 becomes 1 as soon as it becomes 1, but the Q Even if the output falls to 0, it will remain at 1 for a predetermined period of time, which will be explained later, and then become 0.
Output as HPFC. When this HPFC occurs (when it becomes 1), the transfer paper can be set in the stock section through the following process. First, in the sequence, the transfer paper passes through the fixing device 20 in FIG.
2, when the transfer paper is moved in the direction of the tray 30, the passage of the transfer paper is confirmed by the paper detection device A24, and then the transfer paper is held in the paper ejection roller while the above-mentioned HPFC occurs. The rotation of the paper discharge roller 22 is stopped, and the guide plate 26 is moved. After the above-mentioned lateral shift correction control is completed, the roller 22 is reversed and the transfer paper is conveyed at high speed in the direction of the roller 672, and the PDPA is Even if HPFC becomes 0, if HPFC remains 1 for the predetermined period of time, each roller continues to rotate at high speed, and the transfer paper is set in the stock section. At this time, in Fig. 22, the transfer paper moves in the opposite direction to the discharge direction again to set the high-speed preparation position, and when PDPA becomes 1, the D terminal becomes 0 in FF324, so the Q output at this time is When the transfer paper comes out in the direction of the stock section and PDPA becomes 0, the Q output of the FF 326 becomes 0, and after the predetermined time elapses, HPFC becomes 0 and high-speed setting to the stock section is stopped. After that, repeat the set number of times. Therefore, even if papers are accumulated in the stock section, they can be set correctly one after another.

Next, an example of a control circuit for correcting the lateral shift will be explained with reference to FIGS. 7 and 23. First, while the transfer paper is caught by the paper ejection rollers 22 and 48,
When the HPFC stops with the rise of the HPFC, the paper detection device D70 (However, this device is
If no paper is detected by the paper detection device D70 (which is composed of a CdS 70, a lamp 71, and a shielding plate 93, and will be referred to as a paper detection device D70 in the following explanation), the lateral deviation correction control circuit causes the roller 2 to
The reversible motor 90 is driven so that the motors 2 and 48 move in the direction of arrow E in FIG. 7A. on the other hand,
If paper has already been detected, the reversible motor 90 is driven to move in the opposite direction, and the moment paper is detected and the moment paper is no longer detected.
rotation stops, and then the rollers 22 and 27 rotate at high speed until the HPFC is exhausted.
When HPFC returns to 0, the reversible motor 90 is driven again so that the rollers 22, 48 that have been moved for lateral deviation correction return to their original predetermined positions. however,
In this embodiment, the lamp 49 which was temporarily blocked at a predetermined position by the shielding plate 94 in the paper detection device A24 due to the rollers 22 and 48 being shifted laterally.
This was the position when the light returned to the position where it was detected by the CdS 24 again.

Figure 23 shows the lateral shift correction control circuit.
60, and the HPFC is connected to the CP terminal via a terminal 355. Therefore, when the terminal becomes 1, it indicates that the reversible motor 90 should move the rollers 22 and 48 in the direction of arrow E in FIG.
If so, a signal indicating that the vehicle should move in the opposite direction is output. Further, the FF 366 is a circuit for outputting the output terminal Q as 1 for only the time when the reversible motor 90 should rotate, regardless of the rotational direction of the reversible motor 90.

First, connect the D terminal to the power supply (1 signal), and
When a rising signal is applied to the terminal, a 1 signal appears at the Q terminal. First, to start the lateral shift correction, a rising signal of the HPFC input from the terminal 328 is applied to the CP terminal of the FF 366 via the OR gate 364, and the output terminal Q becomes 1. At this time,
The FF 365 stores whether or not the transfer paper is detected by the paper detector D70. That is, if it is not detected now, that is, FF36
If the output of FF 5 is 1, the AND gate 376 outputs Q and FF of FF 365 and 366, respectively.
When the condition that each signal of HPFC is high level is satisfied, a movement command signal in the horizontal left direction (in the direction of arrow E in FIG. 7B) is sent from the terminal 382 via the OR gate 380.
This control signal is output as SSLD, and the reversible motor 90 is driven by this control signal. Furthermore, when the transfer paper is detected by the paper detection device D70, the Q output of FF365 becomes 1, which
connected to one input terminal of AND gate 374;
The other two input terminals are ANDed in exactly the same state.
A lateral right direction movement command signal is sent from the output terminal of gate 374 via OR gate 379 from terminal 381.
Output as SSRD, reversible motor 90
is driven in the opposite direction. Next, when the transfer paper moves laterally to the left and is detected by the paper detection device D70, the signal PDPD from the terminal 360 rises. This signal is AND gate 3
Since the FF365 output terminal and the HPFC are each connected to the other two input terminals as 1 at this time, the signal at the output terminal rises at this time. Since this signal is connected to the R terminal of the FF 366 via the OR gate 372, the circuit 366 is reset at this time, the output terminal Q becomes 0, and the output SSLD becomes 0 via the AND gate 376 and OR gate 380. , and the lateral movement to the left stops. In addition, if the transfer paper is moving horizontally and to the right, PDPD
becomes 0, and this signal is inverted by the inverter 367. That is, it becomes a rising signal to 1, which is applied to one input terminal of AND gate 370. The other two input terminals are AND gate 371
The output of AND gate 370 rises and resets FF 366 via OR gate 372. Further, the signal from the output terminal Q falls, and the SSRD signal falls via the AND gate 374 and OR gate 379, and the lateral rightward movement stops.

Next, the sequence to return to the specified position is to first input two
The output of the AND gate 355 is normally 0, but by adding a signal via the HPFC inverter 362 and a signal via the inverters 362 and 363 to each input terminal, the output from the inverter 362 is applied after the HPFC falls. The output of the gate 355 becomes 1 after a delay of the signal delay time, and then becomes 0 again after the signal delay time of the inverter 363 has elapsed.
Return to The output of this gate 355 is passed through the OR gate 364 as a clock pulse to the FF 366.
It is applied to the CD terminal and the output terminal Q becomes 1 again.
As described above, at this time, HPFC has already become 0, and the signal that has become 1 via the inverter 368 is input to one terminal of the AND gates 375 and 377. Therefore, when the output terminal of the FF 365 is 1, that is, when the rollers 22 and 48 are moving to the left according to the above sequence,
This output is applied to the other input terminal of AND gate 375. When the Q output terminal of FF366 becomes 1, this is added to the other input terminal of AND gate 375, so at this time the output rises and SSRD rises again via OR gate 379 and moves horizontally to the right. Start. Through this movement, the roll reaches a predetermined position, and as described above, at this time, the light from the lamp 49 that was once blocked by the movement of the shielding plate 94 in the paper detection device A24 is irradiated onto the CdS 24 again. When the PDPA falling signal is input from the input terminal 345, a high level signal is output via the inverter 361.
Inputted to one input terminal of AND gate 373,
Furthermore, at this time, since the Q output of the FF 366 is input as a high level to the other input terminal, the signal of 1 from the inverter 361 is applied to the R terminal of the FF 366 via the OR gate 372.
The circuit 366 is reset and the output Q becomes 0.
Through AND gate 375, OR gate 379
SSRD falls. Furthermore, when the Q output of the FF 365 is at a high level, the SSLD rises through the AND gate 377 and the OR gate 380, and moves the displaced rollers 22 and 48 to the left to return to the predetermined position. In exactly the same way, SSLD becomes 0 and the reversible motor 90 is stopped.

Also, at this time, when the transfer paper passes the paper detection device A24 due to the high-speed preparation position setting and preparation position (stock section) paper feeding, if there is almost no movement amount for lateral deviation correction and the roller 22 ,4
If 8 remains in place, the PDPA signal will fall at this time. Therefore, the output of the gate 355 is set to 1 due to the fall of HPFC and becomes FF.
366, and even when the output Q rises, this rising signal is applied to the AND gate 373,
Since it is applied to the R terminal of circuit 366 via OR gate 372, output Q immediately returns to 0 and no lateral movement command SSRD or SSLD is generated.

An example of the electrical control circuit during copying has been described above, but the details have been omitted from the following to avoid complicating the explanation. The first is to reset all the outputs of each flip-flop once the power is turned on, and to generate the detection signal in each position detection device using a contact type switching element such as a micro switch. It is also omitted to explain that these all use chattering prevention circuits, although they do cause chattering. Furthermore, the driver circuits of each device that are driven according to each command are also omitted. Also, the control circuitry of the present invention does not appear in any of the circuits described herein.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of an apparatus showing one embodiment of the present invention, Figs. 2 and 3 are explanatory diagrams showing the relationship between double-sided copying and the optical system, Fig. 4 is an external view of the apparatus, and Fig. 5 is A diagram of the operation panel of the device, FIG. 6 is an explanatory diagram of placing a document on the document table, FIG. 7A is a perspective view of the mechanism for back side copying, and FIG. 8 is an explanatory diagram of the placement of originals such as books in the case of right binding and left binding, FIG. 9 is a perspective view of the paper feed stock section, FIG. 10 is a sectional view of the paper feed stock section, and FIG.
12 and 13 are cross-sectional views of another embodiment, FIG. 14 is an illustration of the paper feed stock section, and FIG. 15 is an illustration of the electrical control system of this embodiment. Block diagram, Figures 16a and 16b are explanatory diagrams of the position of the optical system and paper feed control, Figure 17 is an example of a digital logic circuit used in this embodiment, Figure 18 is a copy command signal generation circuit diagram, and Figure 19 is a block diagram. The figure is a copy execution signal generation circuit diagram, Figure 20 is an optical system movement control circuit diagram, and Figure 21 is a diagram of an optical system movement control circuit.
22 shows a paper feed command signal generation circuit diagram, FIG. 22 shows a high speed preparation position paper feed command generation circuit diagram, and FIG. 23 shows a lateral deviation correction control circuit diagram.

Claims (1)

[Scope of Claims] 1. Feeding a sheet from a storage section and
a first process means for conveying the sheet to a preparation position for imaging a second side of the sheet without subsequently ejecting the sheet; An image forming apparatus comprising a second process means for forming an image on two sides and then discharging the sheet, wherein the first process means includes a rotating means for conveying the sheet with the image formed on the first side to the preparation position; a control means for controlling the rotational operation of the rotation means, and a timer means, wherein the control means reversely rotates the rotation means during conveyance of the sheet having an image formed on the first surface, thereby causing the rotation direction of the sheet to move in the direction of movement of the sheet. , and the rotation means is rotated at high speed to bring the sheet with an image formed on the first surface to a preparation position at high speed, and the high speed rotation of the rotation means is terminated by the timer means. An image forming device characterized by: