JPH0466353B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image forming apparatus such as a copying machine having a variable magnification function.

[Technical Background of the Invention] Recently, various copying machines having variable magnification functions capable of reducing or enlarging copies have been developed and put into practical use. Here, for example, the basic operating principle of a copying machine using the document table moving method will be explained with reference to FIG. Light scanning is performed as the original platen 151 moves by irradiating the original, and the reflected light from the original is passed through mirrors 153, 154, 155, lens 156, and mirror 157 to a rotating surface that has been uniformly charged in advance. By guiding the photoreceptor onto the photoreceptor drum 158 inside, an electrostatic latent image is formed on the photoreceptor drum 158. This photosensitive drum 158
The upper electrostatic latent image is developed with toner, and this toner image is transferred onto paper P, completing one copying process.

In this case, the size of the copying machine is determined by the relative ratio (hereinafter referred to as speed ratio) between the traveling speed of the original (the moving speed of the document table 151) and the rotational speed of the photosensitive drum 158 in the traveling direction of the original. Also, regarding the direction perpendicular to the scanning direction, the lens 156
The optical path length from lens 156 to photoreceptor drum 1
It is determined by the ratio to the optical path length up to 58 (hereinafter referred to as optical path length ratio). Therefore, by changing the speed ratio and optical path length ratio, it is possible to copy a document at any desired reduction or enlargement ratio.

[Problems with the Background Art] However, at present, the magnification changing means for continuously changing the speed ratio and the optical path length ratio is very complicated, and it is difficult to provide general users with a method that allows reduction or enlargement at a certain rate. It's just that it's being done. In addition, there are also restrictions from the paper, for example, if the original is a size other than the specified size, there may be parts that cannot be copied even if you reduce it, or conversely, there may be parts that cannot be copied when you enlarge it, or it may be difficult to copy the entire original. Because of the need to do so, some people had to make copies that were extremely reduced in size, and it was impossible to make copies that filled the paper to fit the size of the paper.

[Object of the Invention] The present invention has been made in view of the above circumstances, and its purpose is to form an image of any size according to the wishes of the user, and to provide an apparatus with excellent operability. The object of the present invention is to provide an extremely convenient image forming apparatus.

[Summary of the Invention] In order to achieve the above object, the present invention includes a first magnification setting means that has at least two fixed magnifications and sequentially selects and sets the fixed magnifications using one magnification selection key, and a magnification up key or a magnification A second magnification setting means for setting an arbitrary magnification using a down key is provided, and the magnifications set by the first and second magnification setting means are displayed, and the magnification of the magnification changing means is controlled according to the settings. I made it so that
Furthermore, when shifting to fixed magnification selection by operating the first magnification setting means from a certain arbitrary magnification, selection is started from a fixed magnification close to the arbitrary magnification.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 show a two-color copying machine of an original platen movement type and equipped with a variable magnification function as an example of an image forming apparatus according to the present invention. That is, 1 is a copying machine main body, and on the upper surface of this copying machine main body 1 is provided a document table 2 that can freely move back and forth in the left-right direction (in the direction of arrow a in the figure). is provided so that it can be opened and closed freely. Here, the document table 2 is driven by a DC brush motor (hereinafter referred to as a scanning motor), not shown. Further, a paper feed cassette 4 is attached to the right side of the main body 1, and a paper discharge tray 5 is attached to the left side. The paper feed cassette 4 is detachably attached to a paper feed section 6 provided at the lower right side of the main body 1. In the paper feed section 6, 7 receives paper _P1 from inside the paper feed cassette 4.
8 is a pair of aligning rollers that convey the paper sent from the paper feed roller 7 (or the automatic paper feeder 11 described later). A detector 9 (consisting of, for example, a detection lever and a microswitch) for detecting paper is provided.
In addition, the cassette cover (top surface) of paper cassette 4
serves as a paper feed tray 10 for manually feeding paper as appropriate (possible when an automatic paper feeder 11 described later is not installed) or for automatically feeding paper. A paper width adjustment guide 12 is also provided on the paper feed table 10 on the paper insertion side of the automatic paper feeder 11. The automatic paper feeder 11 includes a paper feed tray 10
The paper P ₂ placed on top is continuously fed one by one to the paper feed section 5, and it is detachable from the right side of the main body 1, and the details will be explained later.

Further, a photosensitive drum 13 is disposed approximately at the center of the main body 1 . The photosensitive drum 13 is surrounded by an optical system 4, a charging charger 15, a two-color developing device 16, and a transfer charger 1.
7, a stripping charger 18, a cleaning device 19, a static elimination lamp 20, etc. are arranged in this order. Here, the developing device 16 is, for example, the first developing device 1.
The developing device 6 ₁ and the second developing device 16 ₂ are both magnetic brush type developing devices, and are each detachable from the main body 1 . The first developing device 16 ₁ and the second developing device 16 ₂ are selectively driven by a reversible motor (not shown) rotating forward or backward, and this allows the color to be colored black or not. 1
Colors such as red, yellow, blue, and green can be selectively developed. On the other hand, in the lower part of the main body 1, the paper P ₁ or P ₂ sent by the aligning roller 8 is placed on the photosensitive drum 13.
A paper transport path 22 leading to the paper discharge tray 5 via the image transfer section 21 is formed between the transfer charger 17 and the transfer charger 17 . The image transfer section 2 of this paper conveyance path 22
The aligning roller 8 is on the upstream side of 1, and the heat roller 23 as a fixing device is on the downstream side.
and a paper discharge roller 24 are provided.

Here, the optical system 14 includes an exposure lamp 26 whose back is surrounded by a lo reflector 25, a fixed mirror 27, mirrors 28 and 29 whose positions are moved according to the set magnification, a lens 30, and a fixed mirror 31.
The structure has the following features.

Accordingly, the photosensitive drum 13 is driven in the direction of the arrow b in the figure by a drive mechanism (not shown) in synchronization with the document table 2. First, an image of a document that is uniformly charged by the charging device 15 and uniformly irradiated with light by the exposure lamp 26 is formed on the photoreceptor drum 13 by the optical system 14 to form an electrostatic latent image. be done.
The formed electrostatic latent image is developed by the developing device 16 into a developer image, and is sent to the transfer charger 17 side. On the other hand, paper P ₁ or
P ₂ is supplied by aligning roller 8,
The developer image formed on the photosensitive drum 13 is transferred by a transfer charger roller 17 . The sheets P ₁ and P ₂ to which the developer images have been transferred are peeled off from the photoreceptor drum 13 by the peeling charger 18, passed through the paper conveyance path 22, and guided to the heat roller 23, where the transferred images are After being fused and fixed, the paper is discharged to the paper discharge tray 5 by the paper discharge roller 24. on the other hand,
After the developer images are transferred onto the sheets P ₁ and P ₂ , the residual toner remaining on the photosensitive drum 13 is removed by a cleaning device 19 .
The residual image on the photosensitive drum 13 is erased by the static elimination lamp 20, and the photosensitive drum 13 is prepared for the next copying operation.

In the main body 1, an upper frame and a lower frame (not shown) are once pivotally supported via a pivot (not shown), and the other ends of both frames are tilted at a desired angle, for example, about 30°. It is configured so that it can be opened at any time. The upper frame includes an optical system 14, a charger 15, an exposure lamp 26, and a developing device 1 around the photoreceptor drum 13.
6, a cleaning device 19, a static elimination lamp 20, etc. are attached by appropriate means, and furthermore, the document table 2 paper feed roller 7, the upper roller of the aligning roller 8, the upper roller of the heat roller 23, and the paper discharge roller 24. The upper roller is also attached to the upper frame to constitute the upper unit 1A.
The lower frame also includes a paper feed cassette 4, a lower roller of aligning roller 8, and a transfer charger 1.
7, the peeling charger 18, the lower roller of the heat roller 23, the lower roller of the paper discharge roller 24, the paper discharge tray 5, the main motor 32, etc. are attached by appropriate means to constitute the lower unit 1B. ing. After the front cover of the main body 1 is rotated and removed, it is configured so that it can be opened and closed substantially along the paper conveyance path 22 of the paper sheets P ₁ and P ₂ via a housing opening/closing device (not shown). The main motor 32 is a drive source for driving the photoconductor drum 13, the paper feed roller 7, the aligning roller 8, the heat roller 23, the paper ejection roller 24, and other conveyance systems, and as will be described later. The automatic paper feeder 11 is also driven.

Furthermore, an operation panel 33 is provided at the upper end of the entire surface of the main body 1, as shown in FIG.

FIG. 3 shows the automatic paper feeder 11 in detail. That is, 41 is a housing, and this housing 4
A paper feed cassette 4 is slidably inserted through the lower part of the paper feed cassette 1. The right side of the casing 41 is a paper insertion section 24, and when the leading end of the paper _P2 is inserted into the paper insertion section 42, the paper feed table 10 is inserted.
Paper _P2 is placed and set on top. A paper feed roller 43 is provided above the paper insertion section 42 in the housing 41, and there is a paper _P2 near the paper feed roller 43 (that is, there is no paper P2 on the paper feed table 10). A detector 44 (for example, consisting of a detection lever and a microswitch) is provided for detecting whether or not cassette ₂ is inserted. The paper feed roller 43 is attached to the tip of an arm 45 that rotates up and down about a rotation shaft of an upper separation roller 51, which will be described later, as a fulcrum. and,
A protrusion 46 is protruded from the fulcrum side of the arm 45, and the protrusion 46 is locked by a locking pawl 47 that rotates as required. As a result, the paper feed roller 43 is normally located above and away from the paper P ₂ , and when a solenoid (not shown) (hereinafter referred to as a pick-up solenoid) is turned on in response to a paper feed start command, the locking claw 47 rotates upward to release the locking of the protrusion 46, the arm 45 rotates downward under the weight of the paper feed roller 43, and the paper feed roller 43 is brought into pressure contact with the paper _P2 . It's summery. Further, an upper guide 48 is provided between the paper feed roller 43 in the housing 41 and the paper exit side.
A paper guide section 50 is formed by the lower guide 49 and the paper guide path 50, and the tip (left end) of this paper guide path 50 is guided onto the paper feed table 10 at the connection part with the main body 1. Further, the right end of the lower guide 49 extends to the bottom of the paper insertion section 42, and the leading end of the paper _P2 is placed on this extension. In the middle of the paper guide path 50, an upper separation roller 51 which is fixed, a lower separation roller 52 which moves up and down as necessary, and a relay roller 53 are provided in order from the paper feed roller 43 side. The lower separation roller 52 is normally located below and away from the upper separation roller 51, and when a solenoid (not shown) (hereinafter referred to as separation roller solenoid) is turned on, it moves upward and is moved to the upper separation roller 51. 51. The relay roller 53 also includes a lower guide 4.
A leaf spring 54 formed integrally with the tip (left end) of the sheet 9 is in sliding contact with the sheet, and the paper is conveyed between them. Each of the rollers 43, 51, 52, and 53 is driven by the main motor 32 in the main body 1 via a drive transmission mechanism (not shown) (consisting of a plurality of gears and a spring clutch that controls driving force on and off). Power is being transmitted.

Here, the operation of the automatic paper feeder 11 configured as described above will be explained. First, a predetermined number of sheets of paper _P2 are placed and set on the paper feed tray 10. In this case, the leading end of the paper P ₂ is inserted into the paper insertion section 42 and set. In this state, when the pick-up solenoid is turned on by the paper feed start command,
The paper feed roller 43 moves downward and comes into pressure contact with the paper _P2 . Thereafter, when the separation roller solenoid is turned on after a predetermined period of time has elapsed, the lower separation roller 52 moves upward and comes into pressure contact with the upper separation roller 51, and at the same time, the solenoid (hereinafter referred to as bypass supply) that controls the spring clutch By turning on the paper solenoid, the driving force from the main motor 32 is transmitted to the paper feed roller 43, separation rollers 51 and 52, and relay roller 5.
3 rotate, and paper feeding operation is started. That is, the uppermost sheet P ₂ is taken out by the paper feed roller 43 and sent to separation rollers 51 and 52. At this time, the paper feed roller 43
When multiple sheets of P ₂ are sent, the lower separation roller 52
rotates in the direction opposite to the arrow shown in the figure to perform a separation operation and transport only one sheet of paper _P2 . The paper conveyed by these separation rollers 51 and 52
P ₂ is guided to the relay roller 53. When _the paper P ₂ begins to be conveyed in this manner, the pick-up solenoid is turned off and the paper feed roller 43 returns to its original position. transported. The paper _P2 conveyed by the relay roller 53 and the leaf spring 54 is sent along the paper feed table 10,
The paper passes below the paper feed roller 7 on the main body 1 side and is sent to the aligning roller 8, where the detector 9 is turned on. When this detector 9 is turned on, the bypass paper feed solenoid is turned off after a predetermined period of time has elapsed, and the rotation of each roller 43, 51, 52, and 53 is stopped, and at the same time, the separation roller solenoid is turned off and the lower separation roller 52 returns to its original position. This completes the feeding operation for one sheet of paper _P2 . and,
When the number of copies is set to multiple copies, the paper feed roller 43 is restarted by a paper feed start command after a predetermined time has elapsed.
is lowered and the same operation as above is repeated. In this way, automatic paper feeding by the automatic paper feeding device 11 is performed.

4 to 9 show the optical system 14 in detail. This optical system 14 is integrated except for an exposure lamp 26 whose back is surrounded by a reflector 25 and mirrors 27 and 31.
That is, in FIGS. 4 and 5, 61,
A front frame and a rear frame 62 are provided parallel to the base assembly 63, and a guide plate 64 is provided on the front frame 61 to protrude toward the rear frame 62. The guide plate 64 is provided with the front side of the lens carriage 65 on which the lens 30 is mounted and the mirror 2.
The front side of a mirror carriage 66 on which mirrors 8 and 29 are mounted is slidably supported via guided members 67 and 68, respectively. On the other hand, a drive shaft 69 is disposed near the inner side of the rear frame 62 and parallel thereto. This drive shaft 69 is connected to the auxiliary frame 70 of the base assembly 63,
The drive shaft 6 is rotatably supported by bearings 71 and 73 attached to the drive shaft 6.
The rear ends of the lens carriage 65 and the mirror carriage 66 are attached via slidable guides 74, 7 and 75 which are fitted onto the outside of the lens carriage 65 and the mirror carriage 66, respectively.

Therefore, the lens carriage 65 on which the lens 30 is mounted, that is, the lens unit 76, is in the sixth position.
As shown in the figure, the guide plate 64 and drive shaft 69
It is in a state where it can reciprocate in the direction of arrow c in FIG. 5 using as a guide. Further, the mirror carriage 66 on which the mirrors 28 and 29 are mounted, that is, the mirror unit 77 is also connected to the fifth lens unit 76.
It is in a state where it can reciprocate in the direction of arrow c in the figure. Further, the drive shaft 69 is driven by a pulse motor (hereinafter referred to as a lens moving motor) 81 via gears 78, 79, and 80 that are in mesh with each other.

On the other hand, a cam assembly 82 is attached to the lens unit 76.
are fixed by screws, and a link assembly 83 is rotatably supported on the base assembly 63. Rollers 85 and 86 are attached to the L-shaped link 84 of the link assembly 83. They are respectively connected to elongated holes 90 of the bracket 89 of the mirror unit 77. Further, as shown in FIG. 7, a guide 91 is rotatably attached to the cam 87 and engages with a threaded portion 92 of the drive shaft 69. And the drive shaft 69
When the lens unit 76 is rotated, the lens unit 76, which is screwed to the cam assembly 82 via a guide 91, moves in the direction of arrow c.

Note that the magnification can be changed by moving the mirrors 28, 29 and the lens 30 to change the ratio of the optical path length from the document to the lens 30 and the optical path length from the lens 30 to the photosensitive drum 13 (optical path length ratio). This is done by changing the magnification in the direction perpendicular to the scanning direction of the document. That is, during reduction copying (at the maximum reduction magnification), the mirror 2 which is in an integral relationship with the lens 30 and the mirror 29
8 is at the solid line position in Figure 5, and when copying at the same size (magnification
It is arranged to be displaced to the position shown by the dashed-dotted line at the time of 100% magnification, and to the position shown by the dashed-dotted line at the time of enlarged copying (at the maximum magnification).

The lens unit 76 is moved along the following path. That is, the driving force of the lens moving motor 81 is transmitted to the drive shaft 69 via the gears 80, 79, and 78, and as the drive shaft 69 rotates, the guide 91 is moved. Lens unit 76, which is in integral relationship with assembly 82, is adapted to be moved. The amount of movement of the lens 30 is determined by the rotation angle of the lens movement motor 81. Furthermore, the mirror unit 77 is moved along the following path as the lens unit 76 moves. That is, as the cam assembly 82, which is in an integral relationship with the lens unit 76, moves, the roller 85, which is engaged with the arcuate hole 88 of the cam 87, moves, thereby causing the L-shape of the link assembly 83 to move. The link 84 is rotationally displaced, and the roller 8 attached to the L-shaped link 84
6 is also displaced. The mirror unit 77, which is in an integral relationship with a bracket 89 having an elongated hole 90 that engages with the roller 86, is moved.

The amount of movement of the mirrors 28 and 29 is determined by the amount of movement of the mirrors 28 and 29.
The rotation angle is determined by the rotation angle of the L-shaped link 84 of No. 3, and the rotation angle is determined by the shape of the arc-shaped hole 88 of the cam 87. FIGS. 8 and 9 illustrate these movements. That is, FIG. 8 shows the relationship between the cam assembly 82 and the link assembly 83. When the cam 87 moves a distance L in the direction of arrow d, the L-shaped link 84 is rotated by an angle α in the direction of arrow e. do. Note that 93 is a pivot point of the L-shaped link 84. 9 shows the relationship between the link assembly 83 and the bracket 89, and when the L-shaped link 84 is rotated by an angle α in the direction of the arrow e, the bracket 89 moves by a distance S in the direction of the arrow f. Become.

In addition, in FIG. 5, 94 is a photocoupler,
Reference numeral 95 denotes a light shielding plate for turning on and off the photocoupler 94, and these constitute a lens position detection switch 96 for detecting the same magnification position of the lens unit 76.

FIG. 10 shows the operation panel 33,
Copy key 101 for executing a copy operation, interrupt key 102 for specifying an interrupt mode for interrupt copying, numeric keypad 103 for setting the number of copies, copy color (for example, black, red, blue, green)
color selection key 104 for selecting the color that can be copied, color display section 105 for displaying available colors for copying, paper feed selection key 106 for selecting automatic paper feeding by the paper feed cassette 4 or automatic paper feeding by the automatic paper feeder 11, copy total Total counter 107 for counting the number of sheets, liquid crystal display section 1
06 is provided. The liquid crystal display section 108
These include a number display section 109 that displays the number of copies, a status display section 110 that displays various operating states such as paper jams and toner replenishment, and a warm-up display section 1.
11, ready display section 112, color display section 105
a color indicating section 113 that is provided corresponding to the selected color and indicates the selected color; a cassette paper feeding mode display section 114 that displays the automatic paper feeding mode by the paper feeding cassette 4;
It is composed of a bypass paper feeding mode display section 115 that displays the automatic paper feeding mode by the automatic paper feeding device 11, an automatic exposure mode display section 116, and a set roller amount display section 117 in the manual exposure mode. Also provided are an automatic exposure key 118 for setting the automatic exposure mode, a manual exposure key 119 for manually setting the exposure amount, and a magnification setting section 120 for setting the copying magnification. The magnification setting section 120 has a plurality of predetermined fixed magnifications (for example, 71%, 82%, 100%).
%, 122%) magnification selection key 1
21, an indicator (for example, a light emitting diode) 122-1 to indicate that these fixed magnifications have been selected;
25. Any copy magnification (e.g. 71% to 122%)
It is composed of a magnification down key 126 and a magnification up key 127 for setting the magnification, and a magnification display section 128 for displaying the set magnification. Note that the fixed magnification selection using the magnification selection key 121 changes from 71% to 82% to
It is possible to select in the order of 100% → 122% → 71% → ....

FIG. 11 schematically shows the control circuit. That is, 131 is a microcomputer (hereinafter referred to as microcomputer) as a main control section, which controls the entire copying machine. This microcomputer 13
1, various keys 101 to 104, 106, 118, 119, 1 on the operation panel 33 are operated via an input interface 132 such as a data selector.
Input switch 13 such as 21, 126, 127
3. Signals from various switches/detectors 134, etc. necessary for controlling the detectors 9, 44, lens position detection switch 96, etc. are supplied. Also,
From the microcomputer 131, various display systems (the liquid crystal display section 108, displays 122 to 125, magnification display section 128, etc.) 136 are connected via a display driver 135.
At the same time, a control signal is sent to an exposure lamp control circuit 137 that controls the exposure lamp 26. Also, from the microcomputer 131,
Various drive systems (the main motor 32, the developer drive motor, various electric appliances 15,
17, 18, static elimination lamp 20, various solenoids, etc.) 139, and the control circuit 1 of the scanning motor 140 that drives the document table 2.
41 and a control circuit 142 for the lens moving motor 81. Note that the scanning motor control circuit 141 is configured to control the scanning motor 140.
The scanning motor 140 is controlled to rotate accurately in synchronization with the main motor 32, and the rotational speed of the scanning motor 140 is controlled according to the set magnification. The circuit configuration is the same as that of the existing one.

12 and 13 show an example of a data conversion data table used for the magnification setting control of the present invention, which is provided in the microcomputer 131. That is, FIG. 12 shows the first data table for assigning arbitrary magnifications to corresponding magnification area codes. In this case, the magnification area code is "3" for magnification of 71%, "4" for magnification of 72% to 76%, and magnification of 77% to 81%.
is "5", magnification 82% is "6", magnification 83% to 90% is "7", magnification 91% to 99% is "8", magnification 100% is "9", magnification 101% to 110% is "10", magnification 111%~
Each is set to 122% "12". Also,
Figure 13 shows the second data table for converting magnification area codes to corresponding fixed magnifications. In the example, 71%, 82%, 100%, 122%) are stored.

Next, the operation of the above configuration will be explained with reference to the flowchart shown in FIG.
Now, when the power is turned on, the process proceeds to step S1. In step S1, the copying magnification is set to 100% by setting a magnification of 100% in a magnification register (not shown) provided in the microcomputer 131, and the process proceeds to step S2. In step S2, the magnification set in the magnification register is displayed on the magnification display section 128, and the process proceeds to step S3. In step S3, by referring to the first data table, the magnification area code set in the magnification register is stored in a magnification area code register (not shown, hereinafter referred to as a code register) provided in the microcomputer 131. Set and proceed to step S4. step
In S4, it is determined whether the magnification area code set in the code register matches the magnification area code of the fixed magnification, and if they match, the process advances to step S5. In step S5, the displays 122-
The display corresponding to the fixed magnification of the matched magnification area code among 125 is lit, and the process proceeds to step S6. If there is no match in step S4 above, jump step S5 and proceed to step S6.
Proceed to. In step S6, magnification selection key 121
It is determined whether or not the button has been pressed, and if it has been pressed, the process advances to step S7. In step S7, it is determined whether touch flags for remembering that the magnification selection key 121, magnification down key 126, and magnification up key 127 have been pressed have been set, and if they have not been set, the process advances to step S8. ,
If it has been set, proceed to step S9. step
In S9, it is determined whether or not the magnification selection key 121 has been pressed. If it has not been pressed, the process proceeds to step S30, which will be described later, to reset the touch flag; if it has been pressed, the process proceeds to step S10. In step S10, it is determined whether a predetermined period of time (for example, 1 second) or more has elapsed from point A (the point at which the process advances from step S7 to S9), and if it has not elapsed, the step is continued.
Return to S9, and when the time has elapsed, proceed to step S8. In step S8, it is determined whether the magnification area code in the code register is a multiple of "3" or not. If it is a multiple of "3", the process advances to step S11. In step S11, "3" is added to the magnification area code in the code register, and the process proceeds to step S12. In step S8, if the number is not a multiple of "3", the process advances to step S13. In step S13, divide the magnification area code in the code register by "3", if the remainder is "1", subtract "1" from the magnification area code in the code register, and if the remainder is "2", divide the magnification area code in the code register. "1" in the magnification area code within
and proceed to step S12. In step S12,
It is determined whether the magnification area code in the code register is "13" or more. If it is not "13" or more, the process proceeds to step S14, and if it is "13" or more, the process proceeds to step S15. In step S15, the magnification area code in the code register is set to "3" and the process proceeds to step S14. In step S14, the fixed magnification corresponding to the magnification area code in the code register is set in the magnification register by referring to the second data table, and the process proceeds to step S16. Step S16
Now, set the touch flag and follow the steps above.
Return to S2 and repeat the same operation as above.

That is, when the power is turned on, the copy magnification is automatically set to 100% (same size) and displayed on the magnification display section 120. Then, the magnification selection key 121
When is pressed, the mode shifts to fixed magnification selection setting.
In this case, if the magnification selection key 121 is pressed within a predetermined time (for example, within 1 second), fixed magnifications are sequentially selected and set each time the magnification selection key 121 is pressed, and the fixed magnification corresponds to the set fixed magnification. The display unit lights up to indicate that the fixed magnification has been selected and set, and at the same time the fixed magnification is displayed on the magnification display section 12.
Display on 8. Further, when the magnification selection key 121 is pressed for a predetermined time period, fixed magnifications are continuously selected and set at predetermined time intervals (for example, 1 second) while the magnification selection key 121 is pressed, and the magnification selection key 121 is released from being pressed. The moment becomes the newly set copy magnification.
Furthermore, in this case, when the magnification selection key 121 is pressed when an arbitrary magnification other than the fixed magnification is set, selection is started from the fixed magnification closest to the arbitrary magnification that was set immediately before. For example, magnification
When 90% is set, magnification selection key 121
When pressed, selection starts from the fixed magnification of 82%, which is closest to the 90% magnification.

On the other hand, if the magnification selection key 121 is not pressed in step S6, step S17
Proceed to. In step S17, press the magnification up key 12.
It is determined whether or not 7 is pressed down, and if it is pressed down, the process advances to step S18. In step S18,
It is determined whether or not the magnification down key 126 is pressed at the same time, and if it is pressed, the process proceeds to step S6.
Returns to , and if the button has not been pressed, proceeds to step S19. In step S19, it is determined whether the maximum magnification has been set (whether the magnification in the magnification register is equal to the maximum magnification), and if it has been set, step S6
Return to step S20 if the settings have not been completed. In step S20, it is determined whether the touch flag is set, and if it is not set, the process advances to step S21. In step S21, the magnification in the magnification register is increased by, for example, 1%, and the process proceeds to step S16, where the same operation as described above is repeated. If the touch flag is set in step S20, the process advances to step S22. In step S22,
The magnification up key 127 is pressed for a predetermined time (for example, 1
It is determined whether or not the button has been pressed continuously for more than 2 seconds. If the button has not been pressed, the process proceeds to step S16, and if it has been pressed, the process proceeds to step S23. In step S23, the magnification in the magnification register is set to
It increases at a rate of 10%/second and proceeds to step S16, where the same operation as described above is repeated.

On the other hand, if the magnification up key 127 is not pressed in step S17, the step
Proceed to S24. In step S24, it is determined whether or not the magnification down key 126 has been pressed, and if it has been pressed, the process advances to step S25. In step S25, it is determined whether the minimum magnification has been set (whether the magnification in the magnification register is equal to the minimum magnification), and if it has been set, the process returns to step S6, and if it has not been set, the process proceeds to step S26. . In step S26,
Determine whether the touch flag is set or not,
If not set, proceed to step S27. In step S27, the magnification in the magnification register is decreased by, for example, 1%, and the process proceeds to step S16, where the same operation as described above is repeated. In step S26 above,
If the touch flag is set, the process advances to step S28. In step S28, press the magnification down key 126.
Determine whether or not the button has been pressed down continuously for a predetermined period of time (for example, 1 second), and if it has not been pressed down, the
If the button has been pressed, the process advances to step S16; if the button has been pressed, the process advances to step S29. In step S29, the magnification in the magnification register is decreased at a rate of, for example, 10%/second, and the process proceeds to step S16, where the same operation as described above is repeated.

That is, since the currently set copy magnification is displayed on the magnification display section 128, if you want to increase the copy magnification beyond that magnification, press the magnification up key 12.
7, and if you wish to further decrease the magnification, press the magnification down key 126. And both keys 12
6,127, if the press is within a predetermined time (for example, within 1 second), the minimum magnification unit that can be achieved each time a key is pressed (for example, 1%)
The set magnification is increased or decreased using the steps 1 and 2, and the set magnification is sequentially displayed on the magnification display section 128. Also, both keys 1
26, 127 In either case, if the press exceeds a predetermined time, the set magnification is continuously increased or decreased at a predetermined rate (for example, at a rate of 10%/second) while the press is pressed, and which magnification is displayed. 128 sequentially. In this case, each time the content of the magnification display section 128 matches a predetermined fixed magnification, the display 122 to 1 corresponding to the fixed magnification
25 is turned on. And magnification up key 1
27 or the moment when the press of the magnification down key 126 is released becomes the newly set copy magnification.

On the other hand, if the magnification down key 126 is not pressed in step S24, step
Proceed to S30. In step S30, the touch flag is reset and the process advances to step S31. Step S31
Then, it is determined whether or not the copy key 101 has been pressed, and if it has not been pressed, the process advances to step S32. In step S32, it is determined whether or not any other key on the operation panel 33 has been pressed, and if it has been pressed, the process advances to step S33. step
In S33, processing is performed for the pressed key, and the process advances to step S34. In step S32, if no other key is pressed, step S33 is jumped and the process proceeds to step S34. In step S34, it is determined whether or not a predetermined period of time (for example, 30 seconds) or more has elapsed without any key operation on the operation panel 33. If it has not elapsed, the process returns to step S6 and the same operations as described above are repeated. In step S34, if a predetermined period of time has elapsed without any key operation, the process returns to step S1 and repeats the same operation.

That is, if the copy key 101 is not pressed within a predetermined time (for example, 30 seconds) after setting the copy magnification or after completing the previous copying operation, the set magnification is automatically returned to 100% (same size). be.

On the other hand, in step S31, the copy key 1
When 01 is pressed, a copying operation is performed according to the set copying magnification (the magnification set in the magnification register). In other words, when the setting of the copy magnification is completed as described above, the microcomputer 1
31 changes the optical path length from the original to the lens 30 and the optical path length from the lens 30 to the photosensitive drum 13 by driving the lens moving motor 81 in order to change the magnification in the direction perpendicular to the original scanning direction. The mirrors 28, 29 and the lens 30 are moved to positions corresponding to the set magnification. In this case, since a microcomputer is used as the main control unit 131 and a pulse motor is used as the lens moving motor 81, calculation of the amount of movement is very easy, and the number of pulses given to the lens moving motor 81 is very easy. By counting, the position can be determined accurately.

When the user sets the magnification, then sets the number of copies, and then presses the copy key 101, the microcomputer 131 starts the copying operation and drives the main motor 32 and scanning motor 140, respectively. The original set on the original platen 2 is optically scanned and an electrostatic latent image is formed on the photosensitive drum 13. These processes are as described above. In this case, the magnification in the original scanning direction is determined by the ratio (speed ratio) between the moving speed of the original platen 2 (original scanning speed) and the rotational speed of the photosensitive drum 13, as described above. Therefore, the microcomputer 131 operates the scanning motor control circuit 141 according to the magnification set in the magnification register,
By controlling the rotation speed of the scanning motor 140, the speed ratio is made to correspond to the set magnification.

For example, if the configuration is as explained above, 4
A first magnification setting means has two fixed magnifications and sequentially selects and sets the fixed magnification using one magnification selection key 121, and a second magnification setting means sets an arbitrary magnification using a magnification up key 127 or a magnification down key 126. By variably controlling the magnification ratio of the magnification changer (that is, the speed ratio and optical path length ratio mentioned above) according to the settings of the first and second magnification setting means, not only a specific fixed magnification but also an arbitrary magnification can be set. Magnification can be set extremely easily. Therefore, whereas previously it was only possible to reduce or enlarge copies to a specific size, it is now possible to make copies of any size according to the user's wishes, and it is now possible to make copies of any size according to the user's wishes. It is also possible to make large-sized copies, and it is very convenient and has excellent operability. Furthermore, when shifting from a certain arbitrary magnification to fixed magnification selection by pressing the magnification selection key 121, by starting the selection from the fixed magnification closest to the arbitrary magnification, for example, once the magnification is set to the same magnification (100%). Mirrors 28, 29 and lens 30
Not only can unnecessary movements of the user be eliminated, but also unnecessary operations by the user can be eliminated, resulting in even more convenience and excellent operability.

In the above embodiment, when shifting from an arbitrary magnification to fixed magnification selection by pressing the magnification selection key 121, the fixed magnification closest to the arbitrary magnification is selected, regardless of the direction in which the fixed magnification selection order progresses. Although the case has been described in which the selection is started from the fixed magnification, the selection may be started from the fixed magnification closest to the arbitrary magnification in the progression direction of the fixed magnification selection order. In this case, the contents of the first data table in FIG. 12 may be changed as shown in FIG. 15.

In addition, the speed ratio was changed by keeping the rotational speed of the photoconductor drum constant and controlling only the scanning speed of the document, but it is possible to change the speed ratio by controlling both the scanning speed of the document and the rotational speed of the photoconductor drum. It may also be done by Further, the variable magnification means is not limited to the advantageous structure of the embodiment described above, but may have another structure.

Further, although the description has been made using a copying machine as an example, the present invention is not limited thereto, and the present invention is not limited to this, but the present invention optically scans a document and creates an optical image obtained by this scanning.
An image is formed on the photoreceptor at a magnification set for the size of the document by exposing the photoreceptor to light through a variable magnification means whose magnification is controlled according to a preset image formation magnification. It can be applied to any image forming apparatus that performs

[Effects of the Invention] As detailed above, according to the present invention, an image can be formed in any size according to the user's wishes, and moreover, unnecessary movements of the zooming means and the user's Eliminates unnecessary operations and provides excellent operability.
An extremely convenient image forming apparatus can be provided.

[Brief explanation of the drawing]

Figures 1 to 14 show an embodiment of the present invention. Figure 1 is a perspective view showing the external appearance, Figure 2 is a longitudinal sectional front view showing the internal structure, and Figure 3 is an automatic paper feeder. 4 to 9 show the configuration of the optical system. FIG. 4 is a longitudinal side view, FIG. 5 is a plan view, and FIG. 6 is a front view of main parts. Figure 7 is a side sectional view of the main parts, Figures 8 and 9 are diagrams for explaining the operation of the main parts, Figure 10 is a plan view of the operation panel, and Figure 11 schematically shows the control circuit. The block diagram, FIGS. 12 and 13 are diagrams showing examples of data tables used for magnification setting control,
FIG. 14 is a flowchart for explaining the operation, FIG. 15 is a diagram showing an example of a data table in another embodiment of the present invention, and FIG. 16 is a main diagram for explaining the basic operating principle of the copying machine. FIG. 2... Original table, 13... Photosensitive drum, 14...
...Optical system, 26...Exposure lamp, 27, 28, 2
9...Mirror, 30...Lens, 31...Mirror, 81...Lens movement motor, 120...Magnification setting section, 121...Magnification selection key, 122-1
25...Display unit, 126...Magnification down key, 1
27...Magnification up key, 128...Magnification display unit, 131...Microcomputer, 140...Scanning motor, 141...Scanning motor control circuit, 142...
...Motor control circuit for lens movement.

Claims (1)

[Scope of Claims] 1. A document is optically scanned, and an optical image obtained by this scanning is sent to a photoreceptor through a variable magnification means whose magnification is controlled according to a preset image forming magnification. In an image forming apparatus that forms an image on a photoreceptor at a magnification set for the size of the document by guiding and exposing it to a first magnification setting means for selecting and setting a magnification;
a second magnification setting means for setting an arbitrary magnification using a magnification up key or a magnification down key; a display means for displaying the magnification set by the first and second magnification setting means; and the first and second magnification setting means. control means for controlling the magnification ratio of the magnification changing means according to the settings of the first magnification ratio.
An image forming apparatus characterized in that when shifting to fixed magnification selection by operating a magnification setting means, control is performed to start selection from a fixed magnification close to the arbitrary magnification. 2. The image forming apparatus according to claim 1, wherein the fixed magnification close to the arbitrary magnification is the closest fixed magnification regardless of the direction in which the fixed magnifications are selected. 3. The image forming apparatus according to claim 1, wherein the fixed magnification close to the arbitrary magnification is the fixed magnification closest to the fixed magnification in the advancing direction of the fixed magnification selection order. 4. The first magnification setting means can change the fixed magnification for each operation within a predetermined operation time, and if the operation time continues beyond the predetermined time, the fixed magnification can be changed according to the operation time. The image forming apparatus according to claim 1, wherein the image forming apparatus changes continuously. 5 The second magnification setting means is capable of changing the magnification by a certain unit within a predetermined operation time, and when the operation time continues beyond the predetermined time, the magnification is changed to a predetermined value according to the operation time. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus continuously changes at a rate of .