JPS63225251A - Copying machine - Google Patents

Abstract

PURPOSE:To permit registration of the image of an original to the center of copying paper by controlling a process for forming an electrostatic latent image and feeding of the copying paper by the sizes of the copying paper and the original. CONSTITUTION:An original length sensor SE 1 and an original width sensor SE 2 are disposed near the original insertion port of a DF unit 202 to discriminate the size and direction of the original. The control of a margin calculation is executed by dividing the length of the copying paper by a magnification to calculate a scan length, comparing the scan length and the length of original imposing glass 16, calculating the value obtd. by dividing the difference therebetween by 2, i.e., the length l, as a margin is produced if the scan length is shorter, and calculating the timer value corresponding to the length l. The control of the process for forming the electrostatic latent image on a photosensitive drum 1 and the feed control to supply the copying paper at adequate timing to the drum 1 by using the result of the above-mentioned calculation of margin are executed in order to center the original so as to register the image of the original to the center of the copying paper.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a copying machine that forms an image of an original on a photoreceptor and transfers this image onto copy paper.

(Prior art and its problems) Generally, in this type of copying machine, one edge of the original is placed along the edge position of the original glass, so that the edges of the original and copy paper are aligned and copied. It has become so. In other words, alignment control is performed by a timing roller that feeds the copy paper so that the leading edges of the original and the copy paper coincide with each other. According to such control, when the original size is smaller than the copy paper size, or when reduced copying is performed even if they are the same size, the position of the copied image 41 is changed as shown in FIG. There is a problem in that the copy paper 42 is biased towards the leading edge side.

On the other hand, when a worker manually sets the original, he or she can adjust the position of the original so that the image on the copy paper is at the appropriate position, but such adjustment is cumbersome and is inaccurate.

For example, in a copying machine whose maximum scanning distance for an original is A3 size, when making a reduced copy of an A3 original onto A3 size copy paper, the position of the original is adjusted so that the image on the copy paper is at the appropriate position. It is practically impossible to do so.

Further, when using an automatic document feeder, it is difficult to stop the document at an arbitrary position, and it is common to position the document by hitting the reference edge.

Therefore, when using an automatic document feeder, a problem arises in that the image of the document cannot be created at a desired position on the copy paper.

(Technical means for solving the problem) The present invention is capable of aligning the original image to the center of the copy paper (centering) even when the original size is smaller than the copy paper size or when reduced copying is performed. To provide an electronic copying machine, the technical means for this purpose include a means for detecting the copy paper size, a means for inputting or detecting the original size, and a means for detecting the copy paper size so that the image of the original is at the center position or The present invention is characterized by comprising a control means for controlling the electrostatic latent image creation process and the feeding of the copy paper according to the copy paper size and original size so that the copy paper is positioned at an arbitrary position.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view schematically showing the structure of a copying machine equipped with a control device of the present invention, and the structure and operation of the copying machine will first be explained with reference to this diagram.

A photoreceptor drum 1 is supported at approximately the center of the main body of the copying machine 100 so as to be rotatable in the counterclockwise direction in the figure, and around it are an eraser lamp 2, a charging medium 3, an image edge and an inter-image eraser 4, a developing device 6, a transfer charger 7, a separation charger 8, a cleaning device 9, etc. are arranged in this order. The photoreceptor drum l has a photoreceptor layer provided on its surface, and this photoreceptor is uniformly charged by passing through the eraser lamp 2 and the charger 3, and is charged by the scanning optical system l.
It receives image exposure from O through the slit section 5, and an electrostatic latent image is formed on its surface. Image edge and inter-image eraser 4
has a plurality of light emitting diodes arranged in the image width direction, and removes unnecessary charges from the surface of the photoreceptor drum 1 during image formation.

The scanning optical system 10 is installed below the original glass 16 to be able to scan the original image, and includes a light source 17 and a movable mirror 11.
．． 12, 13, a lens 14, and a mirror 15. The light source 17 and the movable mirror 11 move integrally to the left at a speed of v/m (where m: copying magnification) with respect to the circumferential speed V of the photosensitive drum 1 (constant regardless of the same magnification or variable magnification). , and the movable mirror 12.13 is driven to move integrally to the left at a speed of v/2 m. In addition,
When changing the copying magnification, the lens 14 moves on the optical axis and the mirror 15 moves and swings to correct the optical path.

Copy paper is Copy I! Automatic paper feeding mechanism 20 having two upper and lower cassette mounting sections provided on the left side of the main body of No. 100 in the figure.
Alternatively, the paper is fed into the machine by a manual feed mechanism 30 provided above, and after being temporarily stopped by a timing roller 21, it is sent to a transfer section in synchronization with the image formed on the photoreceptor drum 1, The toner image is transferred by the transfer charger 7, separated from the surface of the photoreceptor drum 1 by the separation charger 8, and transferred to the fixing device 23 by the conveyor belt 22.
The image is fixed thereon, and finally it is discharged onto the tray 24.

After the photosensitive drum 1 has been transferred, toner and charges remaining on the surface thereof are removed by a cleaning device 9, an eraser lamp 2, etc., and the photosensitive drum 1 is ready for the next copying process.

Either the automatic paper feed mechanism 20 or the manual paper feed mechanism 30 is selectively used. The switching is performed by a sensor 3 that controls the opening/closing of the manual feed table 31, which is set to cover the manual feed slot 32 when closed and to open the slot 32 when opened, as well as to serve as a guide for manually fed sheets.
6, and in the “open” state, the paper insertion sensor 3
4 detects the insertion of paper, it enters the copy mode with manual paper feed, and switches to the copy mode with automatic paper feed by closing the manual feed table 31 or by a signal from the automatic paper feed selection operation described later or the numeric keypad operation for setting the number of copies. controlled so that Details of this control will be described later.

In the case of automatic paper feeding, the image forming system including the photoreceptor drum 1 is started by operating the print key psw (see FIG. 3) that starts the copying operation of the copying machine 100, and the image forming system including the photoreceptor drum 1 is started during preliminary drive for the photoreceptor drum 1. When the processing is completed, the paper feed rollers 25 and 26 are driven, and the scanning optical system 10 is started to be driven by a scan start signal output as the copy paper is transported, and the copy paper is fed in synchronization with the image forming operation. will be delivered. 2.3 sheets of copy paper are pushed out by the rotation of paper feed rollers 25, 26, and only the top copy paper is conveyed by the next-stage sorting mechanism 27, 28.

In the sorting mechanisms 27 and 28, upper rollers 27a and 28a are rotated in the paper feeding direction, and lower rollers 27b and 28b are rotated in the paper pushing direction, as shown in the figure, and the paper is pushed out together with the topmost paper by the paper feed roller. The subsequent sheets of paper are pushed back by the lower rollers 27b and 28b, and only the topmost sheet of paper is sent out toward the next intermediate rollers 29a and 29b. As will be described later, the intermediate rollers 29a and 29b are associated with the timing roller 21 at the next stage, and their driving is controlled.

On the other hand, in the case of manual paper feeding, when copy paper is inserted from the manual paper insertion slot 32 and the paper insertion sensor 34 detects this, the manual paper feed roller 33 rotates and feeds the copy paper into the machine. At the same time or with a slight delay, photoconductor drum 1 is
starts. Then, the manually fed copy paper is temporarily stopped by the paper leading edge output switch 35 and is on standby.
When the pre-WI drive process including the rotation of the photosensitive drum 1 is completed, the manual paper feed roller 33 rotates again, thereby feeding the paper into the machine.

In addition, each cassette mounting section of the automatic paper feeding mechanism 20 has size detection switches SWll-14 and SW21-24.
The operating state of the switch is changed by the arrangement of protrusions or magnets (not shown) provided on the loaded cassette, and the size of the loaded copy paper is determined by a 4-pin binary code. It has become. Many mechanisms are already known for determining the size of copy paper using a cassette containing copy paper, and a detailed explanation thereof will be omitted.

The copying machine 100 is equipped with an automatic document feeder (hereinafter referred to as ADF) 200, which can perform copying operations in conjunction with each other. ADF 200 is copy machine 1
When the switch SW1 detects that it is electrically connected to the 00 main body and installed at a predetermined position, the ADF
200 and copy@ioo control are associated with each other,
The operation mode of copying machine 100 is switched to ADF mode. ADF mode means that when the copy start key SSW provided on the ADF 200 is operated, the ADF 200 starts operating while the copying machine 100 remains in a standby state, and the original placed on the original tray 203 is transferred to the copying machine. 100 is fed along the top surface of the document placement glass 16 and stopped at a predetermined position, and a start signal is output from the ADF 200 to the copying machine 100 to start the above-mentioned copying operation, and the final scanning movement for that document is completed. Then, an operation signal is output from the copying machine 100 to the ADF 200, and the ADF 20
0 discharges the original onto the paper discharge tray 204. At this time, if the next original is on the original tray 203, the next original is also conveyed to a predetermined position at the same time as the paper is ejected.

The ADF 200 generally has a document feeding section A unit 201 that stocks documents and sends them out one sheet at a time, and conveys the sent document by sandwiching it between the top surface of the document glass 16 and stopping it at a predetermined position on the glass surface. It also includes a document transport section DF unit 202 that sends out documents on a glass surface to a paper discharge tray 204, and the DF unit 202 can also be used alone as a manual document conveyance device. Further, the DF unit 202 is attached to the top surface of the copying machine 100 so that the original glass 16 is exposed.
It can be opened and closed on the 00 main body, and can be used in the same way as a normal document cover.

The ADF 200 further includes an operating section and a sensor as shown in FIG. FIG. 2 is a plan view of the ADF 200, in which an operation section 250 is provided on the top surface of the DF unit 202, a mode setting key 251 and a mode display lamp 252.2.
It has 53.254. Mode display lamp 252.25
3.254 is lit up sequentially each time the mode setting key 251 is operated, and the control mode is accordingly switched to "automatic paper selection", "automatic magnification selection", and "manual", respectively. "Auto Paper Selection" mode fixes the copy magnification, determines the optimal copy paper size from the size of the inserted original and its magnification, and automatically selects the paper source.
This mode feeds copy paper from the selected paper feed section.

In the "Automatic magnification selection" mode, the size of the copy paper to be used is fixed, the corresponding copy magnification is calculated from the size of the inserted original and the size of the copy paper, and the copy magnification is automatically set using the magnification setting mechanism described later. This is the mode in which copying operations are performed with the setting set to .

Near the document insertion opening of the DF unit 202, there is a document length sensor SE1 positioned so that the document can be detected regardless of the size and orientation of the document to be inserted, and two sensors that can be detected or not detected depending on the width of the document. A document width sensor SE2 that changes the state is provided, and the size and orientation of the document are identified based on signals from these two sensors.

Various methods have been proposed to identify paper size, but
In this embodiment, the document length sensor SEI detects the document while it is being conveyed, and the detection time is measured. On the other hand, it is determined whether or not the document width sensor SE2 is detecting the document, and the document size is determined based on both signals. , a method of determining the orientation is adopted. In this method, if the original is a standard paper size, it is possible to identify most sizes using only the length signal, but for the A and B column paper sizes adopted in Japan, Even if the length signal is the same, the size may be different depending on the length and width, so a document width sensor SE2 is provided to determine this.

In the copying mechanism described above, the copying machine is equipped with the operation and control mechanism described below, and is controlled according to the states of various sensors and input paper inches.

FIG. 3 shows the arrangement of operation keys on the operation panel of the copying machine. The operation panel 50 includes a print key PSW for starting the copying operation, a numerical display device 52 capable of displaying 4-digit numerical values, "1", "2", etc.
Numeric keys 61 to 70 corresponding to each numerical value of "9" and "0"
, an interrupt key 80 for specifying interrupt copying, a clear stop key 81, a vapor selection key 82 for specifying the copy paper loaded in multiple stages by size, and an up and down key for changing and specifying the copy image density step by step. Down keys 83 and 84, and a group of keys 8 related to the copy magnification setting device
5 to 93 etc. are arranged. Note that each key corresponds to a normally open open/close switch in circuit terms, and in the circuit diagrams to be described later, the switches are indicated by numbers attached to each key.

The first magnification setting key group 85, 86, 87, 88 is arranged for the purpose of arbitrarily setting the magnification, and when the key 89 for switching the first magnification setting mode is operated, the copying machine is controlled. When any key is operated while the mode is switched to the first magnification setting mode, the numerical value input using the numeric keypad and displayed on the display device 52 is copied to the memory corresponding to the operated key. It is stored as a magnification.

For the second group of magnification setting keys 90, 91, 92, and 93, predetermined copy magnifications are stored in the corresponding memory in advance, and there is no need to set numerical values as in the case of the first group of keys. It is also contemplated that copying operations can be performed based on preset values. Therefore,
The preset copying magnification is, for example, a magnification that is considered to be commonly used for each destination at the factory shipping stage. This will be discussed later.

In this way, the first group of keys allows the user to arbitrarily set the required copying magnification, and the second group of keys allows the user to arbitrarily set the copying magnification required, and the second group of keys is used for commonly used copies, for example, A4-B5, B4→A4 for domestic specifications. ,A
3-A4, or A4→A3, etc., are given different roles in function so that the magnifications corresponding to them are freshened. However, since the numerical value given to the second key group is a general or calculated copying magnification, the actual copy obtained may be slightly different from that copying magnification due to mechanical or design errors. It may be different. For example, even if you select the same size as "x1", the actual size is rx 1.
004J or rx 0.996J. In such a case, switch the control mode of the copying machine to the second magnification setting mode by operating the second magnification setting mode switching key 94 shown in FIG.
It is possible to obtain a desired copying magnification by setting arbitrary numerical values in the memory corresponding to each of the keys 90 to 93 using the same operation as in the first magnification setting mode.

Switches and copying machines 100 corresponding to these individual keys
The various sensors provided in the ADF 200 are associated with a control mechanism 300 including a microcomputer system, as shown in FIGS. 4 to 8.

FIG. 4 shows the relationship among microprocessors (hereinafter simply referred to as CPLJ) 301 to 304 in the control mechanism 300. 301 is a phos that plays a central role in 11I'lH)
In the CPLI, as shown in FIGS. 6 to 8 showing the human output relationship, its serial out terminal 3out is connected to the serial in terminal Sin of each slave side CPU 302 to 304, and the serial in terminal Sin of the host CPU 301 is connected to the slave side CPU 302 to 304. Serial out terminal 5 of CPU 302-304
out and interrupt request terminal INReq are connected to each slave C.
PU interrupt terminal INT and clock output terminal CLKo
ut is the clock input terminal CLKin of each slave CPU
are connected to each other. The interrupt request terminal INTrsq of the host 1-CPU 301 becomes 1H'' at a predetermined cycle, and data blocks containing transfer data to each slave CPU 302 to 304 are sequentially sent to the pass line from its serial out terminal 5out in synchronization with the cycle with a clock signal. to each slave CPU 302-3.
In 04, the data is taken in from the serial in terminal Sin at the "H" timing assigned to itself, and the data is outputted from the serial out terminal 5out in accordance with the clock signal. When the terminal INReq of the host CPU 301 is “L”, each slave CPU 30
2 to 304 are configured to take in the read data, perform calculations, write new data to a register or the like as necessary, and wait for the terminal IN Treη of the host CPU 301 to become H''.

FIG. 5 shows the relationship between the host CPU 301 and the copying mechanism using electrical input/output connections.

The host CPU 301 is provided in the main body of the copying machine 100 and mainly controls a group of keys on the operation panel 50 and the display device 52.
etc. via a decoder 351, and performs determination of key manual power and control of display output of numerical values, light emitting diodes, etc.

There is also a key counter KC that measures the number of fed copies.
The mounting state of the sensor is determined by the input of the detection switch 5WIO. A RAM 352 is banked up by a battery 353, and stores variable data that should be retained even after the power is turned off, such as set magnification data, as will be described later.

FIG. 6 shows the master CPCl 302 and its input/output relationship. The master CPU 302 mainly controls the operation of the copying machine 100 and performs manual judgment of various sensors and switches in the copying machine, and also controls the lighting of each light emitting diode of the inter-image and image edge erasers 4 via the decoder 354.

FIG. 7 shows the ADFCPU 303 and its input/output relationship. ADFCPU303 is provided in ADF200,
It is connected to the mode setting key 251, the copy start key SSW, the original length sensor SEI, the original width sensor SE2, etc., and sends the human power information to the host CPU 301, and controls the lighting of the mode display lamps 252, 253, and 2540.

FIG. 8 shows an optical system CPU 30 related to control of the scanning optical system 10.
4 and its input/output relationship. The optical system CPU 304 is
(host) Receives magnification data via the CPU 301, and accordingly controls the speed control circuit 35 of the scanning drive DC motor M3.
6 and a step motor M4 for controlling the position of lenses and mirrors.
Exposure start switch 5W50 outputs a control signal to the drive control circuit 357 and is activated as the scanning system moves.
, the outputs of the timing switch SWS2 and the image leading edge switch 5WIOI are determined.

FIG. 9 is a flowchart generally showing the control contents and processing procedures in the host CPU 301, and details of individual controls are shown in FIGS. 10 to 20.

First, in FIG. 9, in steps #1 and #2, the magnifications for the memories Q1 to Q4 provided corresponding to the second group of magnification setting keys 90 to 93, which are mainly made at the time of machine assembly or at the time of factory shipment of the machine, are set. Preset processing is executed. The details of this process are shown in the 10th [ffl]. Initial switch sweo in step #l
is a switch that is placed in a normally inoperable position within a copying machine so that it can only be released during assembly at a factory or for service personnel, for example.
The process shown in FIG. 10 is executed only when this switch is operated.

In steps #3, #4, and #5, when the copying machine is not in a copying operation, a process for setting the magnification to each selection key 85-88 or 90-93 is executed.

Details of this process are shown in FIGS. 11 and 12.

In step #6, data for controlling the lens position and motor drive speed is transferred to the optical system CPU 304 for controlling the optical system in accordance with the magnification determined in step #5. When transferring this data, the optical system CPU3
In 04, this is processed by an interrupt. Step #6
The details are shown in FIG.

In step #7, when the copying machine is in the copying operation, in order to position the image 41 in the center of the copy paper 42, as shown in FIG. A margin calculation is performed to calculate the length l.

Details of this step are shown in FIG.

Step #8 shows processing for controlling paper passing based on the length E calculated in step #7. Details of this step are shown in FIG.

Step #9 shows processing when the "automatic magnification selection mode" is selected on the operation unit 250 of the ADF 200. Details of this step are shown in FIG.

In step #IO, other processing is performed.

Step #11 is a time determination step to ensure that the processing time of one routine of control steps executed in the CPU 301 is constant regardless of the processing content, and after waiting for a predetermined time amplifier, step Return to step 3 and repeat the above process.

The flowchart in FIG. 10 shows details of the initial setting process for presetting predetermined numerical values into the memories Q1 to Q4 corresponding to the second magnification setting key groups 90 to 93.

Note that the memories Q1 to Q4 and the memories Q5 to Q8 corresponding to the first magnification setting key group 85 to 88 are R in FIG.
It is set in a predetermined area within AM352.

The numerical values preset in the memories Q1 to Q4 are determined by the on/off state of the switch associated with the operation of the key shown at 95.96 in FIGS. 1 and 5, and specifically, , during machine assembly or factory shipping, the worker turns on and off switches 95 and 96 according to the combinations predetermined by the destination, etc., and closes the initial switch 5W60 (see Figure 1). By doing so, predetermined numerical values are preset in the memories Q1 to Q4. The processing in steps #204 to #207 is performed using the switch 95 stored in the host CPU 301.
．． Table 1 shows a process of storing magnification values for the on/off combinations of switches 95 and 96 in each memory Q1 to Q4.

When arbitrarily setting a numerical value as a copy magnification in the memo IJQ 1 to Q8 corresponding to the first table selection keys 90 to 93 or 85 to 88, the processes shown in FIGS. 11 to 13 are executed.

In FIG. 11(a), steps #501 and #502
Now, when the key 89 or 94 is operated to switch to the copy magnification setting mode, it is determined whether magnification setting is requested for the first or second key group. When the key 89 is operated, the mode is the first copy magnification setting mode, and '1' is set in flag A at step #503. When the key 94 is operated, the mode is set to the second copy magnification setting mode at step #504. Set flag B to "1".

When the key 89 or 94 is operated, the 1000th flag is set to 1 in steps #505 to #508 in either case.
”, and the process of setting the first place display to '0' is executed. That is, when the control of the copying machine is switched to the magnification setting mode, the numerical display device 52 displays "bbbO" (b is blank) and enters a standby state to receive human input from the 1000th digit.

If the numeric keypad is operated in this state, step #510
The type of key is determined in step #511 only when the rlJ key is 61, and 1'' is displayed in the 1000th place.

Note that here, 1 is used for convenience due to the relationship with the numerical display device 52.
Numerical values input as 000th place, 100th place, 10th place, and 1st place will be explained, but the numerical value as a magnification is treated as a decimal number with 3 digits after the decimal point and 4 significant digits.

If the input value is "0" or "2" to "9" in the state of "1000th flag force", step #513
Proceed to step #512 and display 01 in the 1000th place.0 Next, if the input is "0", step #512 is performed along with the case of "1".
Go to , set the 1000th flag to "01", set the 100th flag to "1" and wait for input to the 100th digit, the input will be "
In the case of "2" to "9", the 1000th place flag is set to "0" in step #515, and then the process proceeds to step #518, where the input numerical value is displayed in the 100th place digit.

The processing described above when the 1000th place flag is 1' is based on the premise that values in the range of 0.647 to 1.414 are treated as valid copy magnifications, and therefore, the 1000th place flag is Only "1" or "0" can be displayed. Moreover, by doing this, the key operation when inputting rOJ in the 1000th digit is simplified. Incidentally, even if such processing is executed, there may be a case where the numerical value inputted below the 100th place becomes a numerical value outside the range of the above-mentioned effective copying magnification. The processing at this time will be explained in the subroutine section of FIG. 11(b) and FIG. 12.

When a value is entered in the 1000th place digit, the 100th place flag becomes “1”, and when the numeric keypad is operated in this state, 10
The numerical value corresponding to the operated key is input to the 0th place digit, and in step #518 that value is displayed, and in step #519, the 100th place flag is set to "0" and the 10th place flag is set to '1'. Hereinafter, inputting the 10th place and the 1st place is also performed by operating the numeric keypad.

The flowchart of FIG. 11(b) shows the process of storing the numerical values that are manually input and displayed in the process of FIG. 11(a) into the memory corresponding to the selection key to be operated next.

In step #530, it is first determined whether the mode is the first magnification setting mode or the second magnification setting mode. Step #530 is executed only when either flag A or B is ``1'', so here, for example, only the determination of whether flag A is ``0'' is executed; If it is 1'', it is the first magnification setting mode, so the process proceeds to the stepness 544 and subsequent steps that determine the operation of the first selection key group 85 to 88, and when the flag A is not "1",
That is, when the flag B is 11'', it is the second magnification setting mode, so the process proceeds to step #53 and subsequent steps in which the operation of the second selection key group 90 to 93 is determined.

In the process shown in FIG. 11(b), in any magnification setting mode, the displayed numerical value is basically stored in the memory corresponding to the operated selection key. However, as described above, at this stage, a value that is not within the range of permissible copying magnifications may be displayed. Therefore, after determining the operation of each key, step #5
A subroutine indicated by 32 is executed to prevent numerical values outside the permissible range from being stored in the memory. The process of step #532 is shown in FIG.

In FIG. 12, if the display is not “O”, step #
At 560, it is determined whether the displayed numerical value is smaller than 0.647, and if it is smaller, step #56
2 sets the display to 0.647. Also, in step #563, it is determined whether the displayed numerical value is greater than 1.414, and if it is, the display is changed to 1.4 in step #564.
14.

Therefore, when explained in relation to FIG. 11(b),
When a predetermined selection key is operated in magnification setting mode, if the displayed value is outside the allowable range, the display is set to the allowable limit value, and then the displayed value is stored in the memory corresponding to that key. let When the process of storing numerical values in the memory is executed, the flag A is set to O'' in the first magnification setting mode, and the flag B is set to O'' in the second magnification setting mode, and the process proceeds to step #556.

Steps #556 to #558 are clear/stop key 8
1 (see FIGS. 3 and 5) is operated. When the clear stop key 81 is pressed, bbb 1 is displayed on the display device 52 in steps #557 and #558.
" is displayed and the flag ASB is set to "O". That is, when the clear stop key 81 is operated, the displayed numerical value is cleared and the magnification setting mode is canceled. , the numerical value "1" displayed is "l" as the standard setting value for the number of copies.

FIGS. 13(a) and 13(b) show the processing executed when the second selection key group 90-93 and the first selection key group 85-88 are operated, respectively.

In FIG. 13(a), when any of keys 90, 91, 92 and 93 is operated, light emitting diodes 9Qa, 91a, 92 provided corresponding to the respective keys are activated.
The one corresponding to the operated key among a and 93a (see FIG. 3) is lit, and then the numerical value stored in the memory is transferred to the optical system CPU 304 as magnification data.

In FIG. 13(b), when any of the selection keys 85 to 8 is operated, in this case, the corresponding light emitting diode is turned on as described above, and since the magnification is set to an arbitrary value, step #614 is activated. , #618, #622, #
At 626, the numerical values stored in the corresponding memories Q5-Q8 are displayed on the display device 52. This display is
For example, the setting is such that this is performed only when each key is pressed, and when the key is released, the number of copies set in another storage device is called up and displayed on the display device 52.

In the case of this first selection key group as well, the numerical value stored in the memory corresponding to the operated key is transferred to the optical system CPU 304 as magnification data. As a result, the optical system CPU 304 outputs the 'M control signal to the speed control circuit 356 and the step motor drive control circuit 357 based on the magnification data, thereby making it possible to execute the copying operation at the set copying magnification.

The flowchart in FIG. 15 corresponds to step #7 in FIG. 9 and shows control for margin calculation. First, in step #701, by dividing the copy paper length known from the cassette code by the magnification Calculate the scan length and store the calculation result in the A register.

Next, in step #702, the scan length is compared with 420 (that is, the length of the document placement glass 16 (full scan length)), and if the scan length is shorter, the second
There will be a blank space as shown in Figure 3, so step #703, #
In step 704, the difference between the scan length and the full scan length is calculated, and the value obtained by dividing this difference by 2, that is, the above-mentioned length l, is calculated (14th
(see figure), and store the calculation result in the A register.

Further, in steps #705 and #706, the timer value corresponding to the length l (i.e., length!+peripheral speed of the photoreceptor drum 1)
is calculated, stored in memory A, and returned.

The flowcharts in FIGS. 16(a) and 16(b) correspond to step #8 in FIG. 9, and are for centering the original image to the center of the copy paper. The control of the electrolatent image forming process (hereinafter referred to as image forming process) and the paper feeding control for feeding the copy paper 42 to the photoreceptor drum 1 at an appropriate timing are shown.

First, in steps #801 and #802, the switch 5W212 in front of the timing roller 21 is turned ON (
The leading edge of the copy paper 42 is detected and the switch 5W212 is turned on.
Set timer A at ). Then, in steps #803 and #804, the intermediate roller 29a or 29b is stopped when the cent time of the timer A ends.

In this state, the timing roller 21 is not operating yet, so the copy paper 42 forms a loop in front of the timing roller 21, the size of which is determined by the timer value, as shown in FIG. Wait in this state.

Next, in step #805, it is determined whether or not the contents of memory A are zero. If the contents of memory A are not zero, it is necessary to perform centering, and step #806 to Execute #809. In step #806, the image edge switch 5WIOI is used to detect that the scanning optical system 10 has reached the image edge.
Detect on-edge. Here, the leading edge of the image is the leading edge of the original glass 16, that is, the position of the leading edge where the original is positioned, and this position is first scanned by the scanning optical system 10 and formed on the photoreceptor drum 1. It becomes the tip of the electrostatic latent image.

If YES in step #806, step #807
Turn off the development function, transfer charger 7, and separation charger 8. This is done to do centering.
The electrostatic image formed on the photoreceptor drum 1 is not developed when it passes through the developing section for the first time, that is, during the first rotation of the photoreceptor drum 1, and the developing section is passed through the developing section for the second time. 9. Next, in step #808, timer E1 timer E2,
Then, the timer Z is set, and after this, when the set time ends, a predetermined process is performed. Here, the timer E is set to a time period until the latent image at the leading edge of the image reaches the irradiation area of the eraser lamp 2. This time is a value obtained by dividing the distance from the document image exposure point on the photoreceptor drum 1 to the irradiation area of the eraser lamp 2 by the circumferential speed of the photoreceptor drum 1. In addition, the timer E2 is set when the scanning optical system 10 finishes scanning the maximum length.
This is to turn on the inter-image eraser for erasing extra images beyond that, and the value obtained by dividing the maximum length of the document placed on the document glass 16 by the speed of the light source 17 is cented. The timer 2 is set with a time period until the latent image at the leading edge of the image reaches the original image exposure point again due to the rotation of the photosensitive drum 1.

In step #809, the value of timer W, which is a timer directly related to the centering operation in subsequent processing, is calculated. The value of timer W is determined from the time required for one rotation of photoreceptor drum 1, that is, the value of timer 2, and then the length! This is the value obtained by subtracting the value of memory A corresponding to .

In step #805, if the content in the memory is zero,
l for centering? Since there is no need for Il, steps #806 to #809 are not performed and step #8
When it is determined in step #822 that the timing switch SWS2 is on, the timing roller 21 is turned on and sheet feeding is started in step #823. Timing switch S WS2
is off, switch 5 is turned off in step #824.
If W212 is not off-edge and timer B has not been set or has not yet ended in step #826, then the copy paper 42 is present in the position of switch 5W212, or switch 5W212 and timing roller 21 This is the case where there is no copy paper 42 at the position , and the process returns without performing any processing by the timing roller 21 .

On the other hand, if the contents of the memory A are not zero in step #805 (if centering is to be performed), a determination is made in step #810 as to whether the timing switch SWS2 is on or off. In #811, the timing roller 21 is not turned on, but the timer W is set, and the timing roller 21 is turned on after the time set in the timer W has elapsed.The time of the timer W is ,
As mentioned above, the value is the value obtained by subtracting the value of the memory A corresponding to the length l from the time required for one rotation of the photosensitive drum 1, and the timing roller 21 moves one latent image by the amount stored in the memory. It is turned on relatively quickly relative to the rotation, and as a result, the copy paper 42 is fed that far forward, and the toner image after developing the latent image is transferred from the middle of the copy paper 42. Since the values in memory A are calculated so that the image from the original is formed in the center of the copy paper 42, centering is performed.

In step #813, it is determined whether or not the time set by timer E2 has elapsed. If YES, there is no original image to be imaged, so the inter-image eraser 4 is turned on in step #814. Step #814 is a judgment of timer E, and if timer E is not set or if timer E is still operating, the result is NO, and when timer E expires 68 times, the result is YES. If yes, proceed to step #815, turn off the charger 3 and eraser lamp 2, continue to hold the latent image that has been held without developing it, and move the held latent image to the irradiation position of the inter-image eraser. A timer E3 is set to measure the time. The time of the timer E3 is a value obtained by dividing the distance from the eraser lamp 2 to the inter-image eraser 4 by the circumferential speed of the photoreceptor drum 1. Step #816 is a judgment of the timer E3, and when the timer E3 ends, the result is YES, and if the inter-image eraser 4 is on, the process advances to step #817 to maintain the latent image, and the inter-image eraser 4 is turned on. Turn off.

Next, in step #818, the timer Z is judged, and if YES, in preparation for the latent image passing through the developing section, transfer charger section, and separation charger section for the second time, the developing function is started in step #819. The transfer charger 7 and the separation charger 8 are turned on (that is, the latent image is developed, transferred, and separated during the second pass, and a toner image is formed on the copy paper 42. In step #820, the timer is turned on. When the timer W is judged and the timer W ends, the timing roller 21 is turned on in step #821 to feed the copy paper 42, thereby performing centering as described above.
The processing after 21 is ONL is the processing from step #824 regardless of whether or not centering is performed.

In step #824, it is determined whether the switch 5W212 is off-edge. Detecting the off-edge means that the trailing edge of the copy paper 42 has passed the switch 5W212, and in step #825 (see FIG. 18), the trailing edge of the copy paper 42 has passed the switch 5W212. Furthermore, timer B is set until the timing roller 21 is reliably passed, and the process proceeds to step #826. In step #826, timer B is judged, and the result is YES at the end of timer B, and step #827
Turn off the timing roller 21 with Step #828
Turn on the charger 3 and eraser lamp 2 and return.

Note that the developing function can be turned off by moving the developing device 6 to the left as shown in FIG. Another method is to control the magnetic roller 6a.

FIG. 19 corresponds to step #9 in FIG.
This figure shows control in the "automatic magnification selection" mode using 0. "The automatic magnification selection mode was briefly explained in the operation of the ADF 200 in Fig. 2, but specifically, when this mode is selected by operating the mode selection key 251 shown in Figs. 2 and 7, ,A
When the information is transmitted from the DFCPU 303 to the host CPU 301 and determined in step #901, the following steps #902 to #908 are executed.

When it is determined in step #902 that the copy start switch SSW of the ADF 200 has been operated, the magnification and copy paper size identified using the method described above are encoded and stored in registers, and the appropriate The copying magnification is calculated, the calculation result is transferred to the optical system CPU 304, and the display light emitting diode 85a related to magnification selection is
-88a and 90a-93a are all turned off and a command is issued to the master CPU 302 to start copying. Therefore, in the "automatic magnification selection" mode, the copy magnifications set in advance in the memories Q1-Q8 are Regardless, the copying operation is executed at a magnification calculated based on the original size and the copy paper size.

Therefore, in this control, steps #909 and #91
0, the DF unit 202 was lifted (
When it is determined that SWI is off) or that the "automatic magnification selection" mode is canceled, steps #911 and #91
2, the light emitting diode 93a corresponding to the same magnification setting key 93 is turned on to display the image, and the optical system CP
A process of transferring data in the corresponding memory Q4 to U304 is executed.

As a result, when the user shows an intention not to continue copying in the "automatic magnification selection" mode, the magnification selection display is returned and the same magnification is selected as the standard magnification. In the same sense, the action of removing the key counter KC can also be considered to be an expression of the intention not to continue copying, but in this case,
Selection and display at the same size are performed through the process of the next step #10.

The size of the copy paper loaded in the paper feed unit 400 can be determined by, for example, a depth switch S provided on the unit body.
This can be determined by switching W31 to W34 according to a predetermined 4-bit size code.

FIG. 20 corresponds to step #10 in FIG. 9, and shows a process for changing the operating time of the paper feed roller for each paper feed unit according to the size of the copy paper being fed. .

Steps #1001 to #1005 show a process of turning on the paper feed roller of the selected paper feed unit when the paper feed request from the master CPU 302 becomes '1' during a copying operation.

Steps #1006 to #1012 are a timer for determining the operation duration of the paper feed roller according to the size signal of the copy paper loaded in the selected paper feed unit when the paper feed request is raised. (T-D) to (T-F) are set respectively, and each paper feed roller is stopped when the timer ends.

The timers (T-D) to (T-F) each operate even if the paper to be fed has already protruded close to the separating mechanism when paper feeding starts, due to the relationship with the paper feeding and sorting methods described above. The time is set in relation to the paper size so that the paper feed roller does not rotate after the trailing edge of the paper passes the paper feed roller section.

This control ensures that the paper feeding operation is not obstructed (,
Accidents such as double sheet feeding can be reliably prevented.

Note that the selection of the paper feed unit may be performed either by specifying the paper size and selecting the paper feed unit in which the paper is attached, or by sequentially specifying the paper feed units.

Furthermore, in the above embodiment, as shown in the flowchart of FIG. 15, the image length is determined from the copy paper length and the magnification.
It is practically applicable only in the case of reduced copying. However, if the size of the document can be detected by the ADF 200, the actual document length ID (step #701a) is used instead of the scan length, as shown in the flowchart in FIG. 21, which replaces the flowchart in FIG. This makes it applicable to full-size or even enlarged copies in some cases.

Further, according to the flowchart of FIG. 21, it is also possible to shift the position of the image 41 by an appropriate length from the center of the copy paper 42, as shown in FIG. That is, the shift amount ES can be set by, for example, providing a shift key on the keyboard, turning on this key, and manually inputting the shift amount IS using a numeric keypad.

Alternatively, as in the case of adjusting the exposure amount, a predetermined shift amount XS may be selected using a light emitting diode indicator and up/down keys.

In this case, the document length ID can be detected in various ways using a plurality of light emitting elements and light receiving elements provided on the document cover, or the size of the document can be manually determined.

In the embodiment described above, the copy paper 42 is larger than the original.
Although the description has been made for the case where the image 41 is made smaller than the copy paper 42 by performing reduction copying, it can also be applied to centering when the image 41 becomes smaller than the copy paper 42.

In addition, although we have described the centering of aligning the image 41 to the center of the copy paper 42, the value of the length l shown in FIG. (By this, it is possible to control the image 41 to be located at an arbitrary position along the traveling direction of the copy paper 42.)

(Effects of the Invention) According to the present invention, even when the original size is smaller than the copy paper size or when reduced copying is performed, the image of the original can be aligned to the center of the copy paper. therefore,
No effort is required to position the document for centering, and it is possible to easily center the image even when an automatic document feeder is used.

[Brief explanation of the drawing]

FIG. 1 is a sectional view schematically showing the configuration of a copying machine equipped with a control means of the present invention, FIG. 2 is a plan view of an automatic document feeder that works in conjunction with the copying machine, and FIG. 3 is an operation panel of the copying machine. FIG. 4 is a plan view showing the relationship between each CPU in a microcomputer system related to control of a copying machine, etc.; FIG.
8 are circuit diagrams showing the input/output relationship of each CPU, FIG. 9 is a flowchart generally showing the processing executed in the host CPU, FIGS. 10 to 16, and 1
9 and 20 are flowcharts for explaining the details of each step, and FIGS. 17 and 18 are enlarged partial views of the timing roller section in FIG. 1, and are explanatory diagrams showing the state of paper feeding control. , FIG. 21 is a flowchart showing another embodiment of step #7 in FIG. 9, FIG. 22 is an explanatory plan view showing the relationship between images and copy paper, and FIG. 23 is an image taken by a conventional copying machine. FIG. 3 is an explanatory plan view showing the relationship between the paper and the copy paper. 1... Photosensitive drum, 21... Timing roller,
29M, 29b... intermediate roller, 41... image,
42... Copy paper, 82... Paper selection key, 100
. . . Copying machine, 300 . . . Control mechanism, 301 . . . Host CPU, 302/771. CPU, 400
--Paper feed unit, 5WII~5W14.5W21~
5W24...Size detection switch, S WS2...
・Timing switch, 5W212...Switch for detecting front and rear edges of copy paper, SEI...Document length sensor, SE2
...Document width sensor, m...Copy magnification. Applicant: Minolta Camera Co., Ltd. Figure 2, Figure 4, Figure 3, Figure 5, Figure 7, Figure 5, 5. Engraving of the drawing (no changes to the content) Figure 12, 1! IWJ's Purification 11 (No change in content) Figure 13 (a) 斡薯-该σ Figure 16 (a) Figure 17 Figure 18 Figure 20 Figure 21 Figure 2251 Figure 23 Kushihata can erection procedure Main official document (method) Commissioner of the Patent Office Black 1) Akira Yu 1, Indication of the case 1988 Patent Application No. 59595 2, Name of the invention Copy machine 3, Person making the amendment Relationship to the case Applicant name: Minolta Camera Co., Ltd. 4, agent (K bond 81 Keisai gL6B)

Claims (1)

[Claims] In a copying machine that forms an image of an original on a photoreceptor and transfers this image to copy paper, there is a means for detecting the copy paper size, a means for inputting or detecting the original size, and a means for detecting the original size. 1. A copying machine comprising: control means for controlling an electrostatic latent image creation process and copy paper feeding according to the copy paper size and document size so that the copy paper is located at a central position in a traveling direction or at an arbitrary position.