JPS6236654A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent the titled device from making the misformation of an image by moving variable power lens blocks and also moving an image to feed paper. CONSTITUTION:Copying magnification is coincident with the center of paper P supplied to the center of an original G by operating an original setting reference setting key on a panel 30, the variable power lens block 8 is moved in the (y) direction in accordance with the copying magnification and indicators 51, 52 are moved in accordance with the size of a paper cassette.The indicators 51, 52 are set up on the center position of a fixing scale 2x by driving a motor. Furthermore, the block 8 is moved in the (x) and (y) directions in accordance with the copying magnification and paper size. Consequently, copying can be attained on a practiced original setting position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image forming apparatus applied to, for example, an electronic copying machine.

[Technical Background of the Invention and Problems Therewith] As is well known, some electronic copying machines have a document set reference point at the center of the document table, and others have a document set reference point on one side of the document table. Since the setting standards for these originals are fixed by the copying machine, it is fine if the user uses a copying machine with which the setting standards are familiar, but if not, it may be difficult to use because the setting standards are different from normal ones. There is,
In some cases, there is a problem in that a copying error occurs, such as an image being formed only on a portion of the paper.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to allow originals to be set according to familiar standards, and even if the original setting standards change, the image forming area can be adjusted accordingly. An object of the present invention is to provide an image forming apparatus that can give instructions and prevent image forming errors.

[TR essential for invention]

The present invention makes it possible for the user to move, for example, a variable magnification lens block along a fixed scale that serves as a reference for setting an original, and to move an image formed on a sheet of paper supplied with a center reference. The document setting standard can be selected as required, and by moving a pointer provided at the bottom of the document table, the vertical image forming range for the document image can be indicated.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 4 and 5 schematically show an image forming apparatus of the present invention, such as a copying machine. That is, 1 is a main body of a copying machine, and a document table (transparent glass) 2 is fixed to the upper surface of the main body 1 to support a document. The document table 2 is provided with fixed scales 2X and 2y (the fixed scale 2y is shown in FIG. 1) along the width direction and the length direction of the document table, respectively, each indicating a document setting reference. Near the table 2, a document cover 11 and a work table 12, which can be opened and closed, are provided. The original placed on the original platen 2 is moved back and forth by an optical system consisting of an exposure lamp 4 and mirrors 5, 6, and 7 in the direction of arrow a along the lower surface of the original platen 2. It is designed to be exposed and scanned at times.

In this case, mirror 6.7 moves at half the speed of mirror 5 so as to maintain the optical exposure length. The light reflected from the original by the scanning of the optical system, that is, the light reflected from the original by the light irradiation of the exposure lamp 4, is reflected by the mirror 5.6.7, passes through the variable magnification lens block 8, and then passes through the mirror. 9 and guided to the photoreceptor drum 10,
An image of the original is formed on the surface of the photosensitive drum 10.

The photosensitive drum 10 rotates in the direction of arrow C in the figure, and the surface is first charged by a charging device 11, and then an image is exposed to slit light to form an electrostatic latent image on the surface. This static MM image is made visible by applying toner by a developing device 12.

On the other hand, the paper (image-forming object) P is taken out one by one from the selected upper paper feed cassette 13 or lower paper feed cassette 14 by the delivery roller 515 or 16, passes through the paper guide path 17 or 18, and then passes through the registration rollers. versus 19
and is guided to the transfer section by this pair of registration rollers 19. Here, the paper distribution paper cassettes 13 and 14 are removably provided at the lower right end of the main body 1, and one of them can be selected from an operation panel to be described later. The cassette size of each of the paper feed cassettes 13 and 14 is detected by a cassette size detection switch 602, respectively. This cassette size detection switch 60r
, 602 are constituted by a plurality of microswitches that are turned on and off in accordance with the insertion of cassettes of different sizes.

The paper P sent to the transfer section comes into close contact with the surface of the photoreceptor drum 10 at the transfer charger 2o, so that the toner image on the photoreceptor drum 10 is transferred by the action of the charger 20. Ru. The transferred paper P is electrostatically peeled off from the photoreceptor drum 10 by the action of a peeling charger 21 and conveyed by a conveyor belt 22, and then transferred to a fixing roller 23 as a fixing device provided at the end of the conveyor belt 22. The transferred image is fixed by passing through this area. After fixing, the paper P is transferred to a tray 25 outside the main body 1 by a pair of paper ejection rollers 24.
It is becoming more and more popular. After the photosensitive drum 10 has been transferred, the charge is removed by the charger 26, residual toner on the surface is removed by the cleaner 27, and afterimages are roughly erased by the charge removal lamp 28, so that the photoreceptor drum 10 returns to its initial state. It's starting to go back. Note that 29 is a cooling fan for preventing the temperature inside the main body 1 from rising.

FIG. 6 shows the operation panel 30 provided on the main body 1. 301 is a copy key for instructing the start of copying; 302
303 is a display unit that displays the operating status of each part and paper jams, etc.; 304 is a cassette selection key that selects the upper and lower paper feed cassettes 13 and 14; 305 is the selected cassette 306 is a magnification setting key for setting the copy enlargement/reduction magnification in a predetermined relationship, 307 is a zoom key for steplessly setting the enlargement/reduction magnification, and 308 is a display for displaying the set magnification. 30g is a density setting part for setting copy density. 30a and 30b are document setting bases t, respectively.
1! Setting keys 30c and 30d are light emitting display elements that indicate that the set reference setting keys 30a and 30b have been operated, respectively.

FIG. 7 shows an example of the configuration of a drive source for each drive section of the copying machine configured as described above, and is composed of the following motors. That is, 31 is a lens motor, which is a motor for moving the position of the lens block 8 that performs magnification change. 32 is a mirror motor, and the distance N between the mirror 5 and the mirror 6.7 is used to change the magnification.
This is a motor for changing the optical path length. 33 is a scanning motor, which connects the exposure lamp 4 and mirror 5;
This is a motor for moving the mirror 6.7 for scanning the original. A shutter motor 34 is a motor for moving a shutter (not shown) for adjusting the charging width of the photosensitive drum 10 by the charger 11 during zooming.

A developing motor 35 is a motor for driving the developing roller of the developing device 12 and the like.

36 is a drum motor, which is a motor for driving the photosensitive drum 10. Reference numeral 37 denotes a fixing motor, which is a motor for driving the paper conveyance path 22, the pair of fixing rollers 23, and the pair of paper discharge rollers 24. 38 is a paper feed motor, which is a motor for driving the delivery rollers 15 and 16. 39 is a paper feed motor;
This is a motor for driving the registration roller pair 19.

A fan motor 40 is a motor for driving the cooling fan 29.

FIG. 8 shows a drive mechanism for reciprocating the optical system. That is, the mirror 5 and the exposure lamp 4 are supported by a first carriage 411, and the mirror 6.7 is supported by a second carriage 422, and these carriages 411.412 are guided by guide rails 421.422 in the direction of arrow a. It can be moved in parallel. That is, the four-phase pulse motor 33 drives the pulley 43. An endless belt 45 is stretched between the pulley 43 and the idle pulley 44, and one end of a first carriage 411 that supports the mirror 5 is fixed to a midway portion of the belt 45. On the other hand, a second carriage 422 supporting the mirror 6.7
The guide portion 46 includes two grooves spaced apart in the axial direction of the rail 422.
Two pulleys 47.47 are rotatably provided, and a wire 48 is stretched between these pulleys 47.47. One end of this wire 48 is fixed to a fixing part 49, and the other end is fixed to the fixing part 49 via a coil spring 50. Further, one end of a first carriage 411 is fixed to a midway portion of the wire 48. therefore,
As the pulse motor 33 rotates, the belt 45 rotates and the first carriage 41! moves, and the second carriage 422 also moves accordingly. At this time, pulley 4
7. Since 47 acts as a movable pulley, the first carriage 4
1! In contrast, the second carriage 422 moves in the same direction at 1/2 the speed. Note that the first and second carriages 41
The moving direction of 1.412 is controlled by switching the rotation direction of the pulse motor 33.

Further, the first carriage 41 lid is moved to a predetermined position (home position according to the magnification) by driving a motor 33 according to the paper size and magnification. Then, when the copy key 30 is pressed, the first
The carriage 411 is first moved toward the second carriage 412, and then the lamp 4 is turned on and moved away from the second carriage 412. When scanning of the original is completed, the lamp 4 is turned off and the first carriage 411
is returned to the home position.

Further, on the document table 2, a copyable range corresponding to the specified paper is displayed. In other words, cassette selection key 3
If the paper size specified by 04 is (PxlPy) and the copy magnification specified by the magnification setting keys 306 and 307 is K, then the copyable range (X, ¥), ``x-
Px/KJ.

ry=Py/KJ. This copyable range (X%y)
As shown in FIG. 1, the X direction is indicated by pointers 51 and 52 provided on the back of the fixed scale plate 2x provided at the left end of the document table 2, and the 41! It is displayed by a scale 53 and a fixed scale 2y provided on the upper surface of the screen.

The fixed scale plate 2x is composed of a transparent part 2a and a white opaque part 2b. The width of the transparent portion 2a is the maximum copying width X8. As a result, the guideline 51.52
When it exceeds the maximum copying width X9, it moves to the lower part of the opaque portion 2b and is no longer visible to the operator.

As shown in FIG. 9, the above-mentioned pointer 51
It is provided on a belt 57 that is stretched between the As shown in the figure, the pointer 52 is provided on a belt 57' that is stretched between pulleys 54' and 55'. The pulleys 55°55' are rotated by motors 58,58-, respectively, and the motors 58,58-
The pointer 51.5 is driven individually according to the setting standard of center or one side, paper size and magnification.
The positions of the two and the distance between them can be changed. The range X indicated by the above-mentioned pointer 51.52 is the width in the vertical direction as the copyable cylinder surface, and the maximum movement Dffi of the pointer 51.52 is the width X A m a
It is X Bm a X.

For example, if the setting standard is center and the paper size is A4,
When the magnification is equal to the same magnification, the pointers 51, 52 are set at positions based on the center of the fixed scale 2x, as shown in Fig. 1 <a>, by rotating the motors 58, 58 individually. It has become so. Also, if the setting standard is one side, the paper size is A4, and the magnification is 1x, the motor 58
By individually rotating ゜58', the pointer 51゜5
2 is set at a position with reference to the end of the fixed scale 2y, that is, the fixed scale 2x, as shown in FIG. 1(C).

FIG. 10 shows a drive mechanism for the variable magnification lens block 8. As shown in FIG. The motor 31 is connected to a first carriage 411
A lead screw 61 disposed along the moving direction (X direction) is rotated. Bushes 631 and 632 provided at one end of the board 62 are screwed into this lead screw 61.
1 is rotated, the substrate 62 is moved in the X direction.

A guide member 621 is provided at the other end of the substrate 62, and the guide member 621 is slidably engaged with the guide rail 64. Further, the substrate 62 includes a substrate 62 .
A movable body 65 is provided, which is movable in a direction (X direction) orthogonal to the above, and to which the variable magnification lens block 8 is attached. That is, supports 651. are provided at both ends of the moving body 65.
652 are provided, and these supports 651, 652 are guided and held by guide members 661, 662 provided on the base plate 62. Further, a rack 653 is provided on the longitudinal side surface of the support body 651, and a pinion 68 rotated by a pulse motor 67 provided on the base plate 62 is meshed with this rack 653. Therefore, the variable power lens block 8 is moved in the X direction by driving the motor 67. Note that the micrometers 91 and 692 detect the initial positions of the substrate 62 and the moving body 65, respectively.

Next, the relationship between the operation of the variable magnification lens block 8 and the image formed will be explained. In FIG. 11(a), the focal length of the variable magnification lens block 8 is f, and the optical path length from the document table 2 to the variable magnification lens block 8 is ya1. Assuming that the optical path length is yb and the total optical path length from the document table 2 to the photosensitive drum 10 is yc, the optical formula is expressed as follows.

1/f-1/Va+1/Vb Also, the magnification is expressed as -yb/ya. Since the focal length f of the variable power lens block 8 is constant, it can be seen that in order to focus during variable power, it is necessary not only to change the total optical path length yC but also to change ya or yb. These ya and yb can be changed by moving the variable power lens block 8 in the y direction. Further, the total optical path length yc can be changed by moving the second carriage 412 and changing the position of the mirror 6.7.

On the other hand, as shown in FIG. 11(b), the distances between the document table 2, the variable magnification lens block 8, and the photosensitive drum 10 are kept constant, and the variable magnification lens block 8 is moved by the motor 67 in the X direction, for example, by a distance. When moving by Xl, the photosensitive drum 10
The upper image is moved by a distance #X2 given by:

X 2 = X I X V b / ya In the case of equal size copying, X 2 = 2Xt. In this way, by moving the variable magnification lens block 8 in the X direction, the center of the copied image can be moved.

FIG. 12 shows the overall control circuit, showing the main processor group 71 and the first . Second sub-processor group 72.
It is mainly composed of 73. The main processor group 7
Reference numeral 1 denotes a high-voltage transformer 76 that detects input from an input device 75 such as an operation panel 3o and various switches and sensors, such as the cassette size detection switches 601 and 602, and drives the various chargers, the static elimination lamp 28, and the The blade solenoid 27a of the cleaner 27, the heater 23a1 of the fixing roller pair 23, the exposure lamp 4, and each of the motors 31 to 40 are controlled to perform the above-mentioned close-up operation, and the motor 58.58'' is controlled. The guides 51 and 52 are moved in accordance with the copyable range, and the motor 67 is controlled to move the original image in accordance with a document setting standard, which will be described later.

Among the motors 31 to 40.67, motor 35.37
．． A toner motor 77 that supplies toner to the developer 40 and the developing device 12 is controlled by the main processor group 71 via a motor driver 78, and the motors 31 to 34 and 67 are controlled by the first sub processor group via a pulse motor driver 79. The motors 36, 39, 38, 58° 58- are controlled by the second sub-processor group 73 via a pulse motor driver 80. Further, the exposure lamp 4 is connected to the main processor group 7 via a lamp regulator 81.
1, and the heater 23a is controlled by the main processor group 71 via the heater control section 82. Then, from the main processor group 71, the first. 2nd subprocessor group 7
Drive and stop commands for each motor are sent to 2.73, and
A status signal indicating the drive/stop state of each motor is sent from the second sub-processor group 72, 73 to the main processor group 71. Further, the first sub-processor group 72 receives position information from a position sensor 83 that detects the initial positions of the motors 31 to 34.67.

FIG. 13 shows an example of the configuration of the main processor group 71. That is, 91 is a one-chip microcomputer (hereinafter simply referred to as microcomputer), which detects human input of keys on an operation panel (not shown) and controls various displays via an input/output board 92. Further, the microcomputer 91 is expanded by input/output ports 93-96. The input/output boat 93 is connected to a high voltage transformer 76, motor driver 78, lamp regulator 81, and other outputs, and the input/output boat 94 is connected to a size switch for detecting paper size and its individual inputs. A copy condition setting switch and its respective inputs are connected to the boat 95.

Note that the input/output port 96 is an option.

FIG. 14 shows an example of the configuration of the first sub-processor group 72. That is, 101 is a microcomputer, which is connected to the main processor group 71.

102 is a programmable interval timer for controlling the phase switching interval time of the pulse motor;
By setting a set value from 1, a count is performed based on the set value, and when the count is out, an end pulse is output to the interrupt line of the microcomputer 101. Said timer 10
A reference clock pulse is input to 2. Furthermore, the microcomputer 101 receives position information from the position sensor 83 and is connected to input/output boats 103 and 104. The input/output boat 104 is connected to the motors 31 to 31 through the pulse motor driver 79.
34.67 is connected. The input/output board 103 is used, for example, to output status signals of each pulse motor to the main processor group 71.

FIG. 15 shows the configuration of the second sub-processor details 73. That is, 111 is a microcomputer, which is connected to the main processor group 71.

112 is a programmable interval timer for controlling the phase switching interval time of the pulse motor;
By setting a set value from 1, it counts based on it, and outputs an end pulse when the count is out. This termination pulse is latched by the latch circuit 113, and its output is supplied to the interrupt line and input/output board input line of the microcomputer 111. Further, an input/output boat 114 is connected to the microcomputer 111, and motors 36, 38, 39, 58, 58- are connected to this input/output boat 114 via the pulse motor driver 80.

Figure 16 shows the control circuit of the pulse motor.
The input/output boat 121 (corresponding to the input/output boats 104 and 114 in FIGS. 13 and 15) has a pulse motor driver 1.
22 (corresponding to the pulse motor driver 79.80 in FIG. 12) is connected to the pulse motor driver 122, and the pulse motor 123 (the pulse motor 31 to 34.
．． 38, 39, 58, 58, 67) each winding A,
B, A, and B are connected.

Figure 17 shows a method for controlling the speed of a pulse motor.

Figure (a) shows the speed curve of the pulse motor, and Figure (b) shows the speed curve of the pulse motor.
) indicates the phase switching interval. As is clear from this figure, the phase switching intervals are long at first, gradually shorten, eventually become equal intervals, and then gradually lengthen again until they stop. In other words, this indicates the through-up and through-down of the pulse motor, starting from the self-starting region, being used in the high-speed region, and finally falling down. In addition, tl, t2
...tx indicates the time of the phase switching interval.

Next, the gist of this invention will be explained.

In this invention, the reference for setting the original can be selected by the setting keys 3a and 3b, such as the center of the fixed scale 2x of the original table 2, or one side of the fixed scale 2y, and the paper can be set on the fixed scale 2x of the original table 2. It is designed to be supplied with reference to the center of the area.

FIG. 18 shows the paper supply section described above.

In this manner, when the paper setting reference corresponds to the center of the document table 2, the delivery rollers 15 and 16 are configured to come into contact with the center of the paper. Therefore, when taking out the paper from the cassette, there is no so-called skew in the paper, so that paper can be fed satisfactorily. On the other hand, when the paper is fed from one side, the delivery roller does not come into contact with the center of the paper, so that the paper taken out from the cassette is likely to be skewed when the paper is fed.

In the above configuration, the operation will be explained. When the document setting standard setting key 30a of the operation panel 30 is operated, the document setting standard is set to the center of the fixed scale 2x. In this case, if the copying magnification is set to the same magnification as shown in FIG. 1(a), or if the reduced magnification is set as shown in FIG. 1(b), Since the centers of the sheets of paper P coincide with each other, the variable magnification lens block 8 adjusts the magnification as shown in FIG.
It is moved in the y direction shown in , but not in the x direction.

Further, in this case, the hands 51 and 52 are moved according to the size of the selected paper cassette.

That is, when the upper cassette in which A4 size paper is set is selected, the main processor group 71 uses the microcomputer 111 to drive the motors 58.about.58-, thereby producing the image shown in FIG. ), the pointers 51 and 52 are set at positions based on the center of the fixed scale 2x.

On the other hand, in the above state, when the document setting standard setting key 30b is operated, the document setting standard is set to the fixed scale 2y. In this case, as shown in FIGS. 1(c) and 1(d), even if the copying magnification is equal to or reduced, the center of the document and the center of the paper P do not coincide. For this reason,
The variable magnification lens block 8 is connected to the magnification setting key 306.
X according to the copy magnification set by and the paper size selected by the cassette selection key 304.
direction, y direction.

That is, the movement Dffi of the variable power lens block 8 is determined as follows. As shown in FIG. 2, the distance from the center of the document table 2 to one end of the fixed scale 2x is xi.
, the length from the center of paper P to one end is X2 (=P
/'2), the moving distance of the variable magnification lens block 8 according to the set magnification is y, the variable magnification lens block 8 at the same magnification (shown by a solid line), and the variable magnification lens at a predetermined copy magnification. The angle between the line connecting the centers of the blocks 8 (indicated by dotted lines) and the optical axis of the variable power lens block 8 shown by the solid line is θ, and the variable power lens block 8, document table 2, and paper shown by the dotted lines are θ. Letting the distances to P be a and b, respectively, the relationship between these is (Xo +
b-1/f The scaling factor has the following relationship: 1(-b/a Solving the above equation, it can be seen that x-F(K, Xa, f, P). Here, xa,
Since f is a constant determined by the copying machine, the above equation is transformed as x=F (KSP>).In other words, the moving distance In other words, once the magnification ratio and paper size are set, the amount of movement of the magnification changing lens block 8 can be determined.As a method for moving the magnification changing lens block 8, stores the number of pulses corresponding to x-F (K, P) in a storage unit such as a ROM, and when the variable magnification K and paper size P are input, the number of pulses corresponding to x-F (K, P) is The stored number of pulses may be read out and the motor 67 may be driven in accordance with this number of pulses.

Further, in this case, the hands 51 and 52 are moved according to the size of the selected paper cassette.

That is, when the upper cassette in which A4 size paper is set is selected, the main processor group 71 uses the microcomputer 111 to drive the motors 58° and 58', thereby producing the image shown in FIG. 1(C) or (d). ), set the pointers 51 and 52 at positions based on the fixed scale 2y.

FIG. 3 shows the operating state of the variable magnification lens block 8 according to the document set position, copy magnification, and paper size. FIG. 5A shows a case where an original G having a width of G2 is set in the center M and is copied at the same size onto a sheet P having a width of P2.

In the same figure (b), one side of the document G with a width of G3 is used as a reference, and the width is P.
This shows a case where a copy is made at the same size on paper P of s. FIG. 2C shows a case where an original @G with a width of G4 is used as a reference on one side, and an enlarged copy is made on a sheet P with a width of P4. The same figure (d
) shows the case where an original G having a width of Gs is used as a one-sided reference and an enlarged copy is made onto a sheet P having a width of Ps.

According to the embodiment described above, setting reference setting keys 30a and 30b for specifying the document setting position are provided, so that the user can specify the document setting position as required. Also,
When changing the setting position of the original, the vertical copy range of the original is displayed with a guide according to the change. Therefore, it is possible to perform copying at a familiar original setting position, and it is also possible to set the original according to the guideline, so it is possible to prevent copying errors due to incorrect setting of the original.

Also, the lens block 8 for variable magnification is used as a base for setting originals! 1!
Setting keys 30a, 30b1 and magnification setting key 30s
, and can be moved according to the operation of the cassette selection key 304, so that the image is always formed in the center of the paper. Therefore, even if the document setting standard changes, the paper can be sent out with the center standard, and there is no need to replace the cassette.

Roughly speaking, the setting reference for the paper P corresponds to the center of the fixed scale 2x, and the delivery rollers 15 and 16 are brought into contact with the center of the paper.

Therefore, the supplied paper is unlikely to be skewed, and the reliability of paper feeding is high.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without changing the gist.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to set originals according to familiar standards, and even if the original setting standards change, the image forming range can be specified accordingly, thereby preventing copying errors. It is possible to provide an image forming apparatus that can perform

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the image forming apparatus according to the present invention, and FIG. 2 is a partially cutaway plan view of only the main part showing the position where a document is set, and FIG. 2 is a plan view for explaining the moving state of the lens. 3 is a schematic configuration diagram shown to explain the movement state of the lens in various setting states, and FIGS. 4 and 5 show the configuration of the image forming apparatus.
Fig. 4 is an external perspective view, Fig. 5 is a side sectional view, Fig. 6 is a plan view showing the configuration of the operation panel, Fig. 7 is a perspective view showing the configuration of the drive section, and Fig. 8 is the drive of the optical system. FIG. 9 is a perspective view schematically showing the mechanism, FIG. 9 is a perspective view schematically showing the relationship between the pointer and the fixed scale plate and the pointer drive mechanism, and FIG. 10 is a perspective view showing the configuration of the variable power lens block. , a perspective view showing only the main parts, Fig. 11 is a diagram showing the relationship between the operation of the variable magnification lens block and the image formed, Fig. 12 is a block diagram showing the overall control circuit, and Fig. 13 is the main A configuration diagram of the processor group, FIG. 14 is a configuration diagram of the first sub-processor group,
Fig. 5 is a block diagram of the second sub-processor group, Fig. 16 is a schematic block diagram showing the control circuit of the pulse motor, Fig. 17 is a diagram for explaining the speed control method of the pulse motor, and Fig. 18 is a diagram of the paper FIG. 3 is a perspective view of the main parts of the delivery section. DESCRIPTION OF SYMBOLS 1... Main body, 2... Original table, 2X... Fixed scale, 2a... Transparent part, 2b... Opaque part, 8...
Lens block for variable magnification, 10...photosensitive drum, 30
...Operation panel, 30a, 30b...Set reference setting key, 51.52...Pointer, 58.58'...Motor, 71...Main processor group. Applicant's agent Patent attorney Takehiko Suzue (a) Figure 1 (C) (d) Figure 1 (a) Figure 3 (b) Figure 3 Figure 3

Claims (1)

[Claims] a scanning device that moves along the document table and optically scans the document placed on the document table according to the set reference; and an image carrier on which an image corresponding to the document image guided by the scanning device is formed. an image forming apparatus comprising a body, a supplying means for supplying a transfer material corresponding to the set reference center of the document, and a transfer means for transferring an image formed on the image carrier to the supplied transfer material. The apparatus includes: a changing means that is movable along the document setting reference and changes the imaging position of the image on the image carrier; a setting means that sets the document setting reference to the center or one side of the document table; The apparatus is characterized by comprising a control means that operates the changing means in accordance with the settings of the setting means and moves a pointer provided at the bottom of the document table that instructs the image forming range in the vertical direction with respect to the original image. Image forming device.