JPH068970B2 - Image forming device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image forming apparatus applied to, for example, an electronic copying machine.

[Technical background of the invention and its problems]

Generally, an electronic copying machine has a function of copying a document image as it is on a sheet or enlarging or reducing a document image for copying.

By the way, an original image may have an unnecessary portion. However, the conventional copying machine cannot copy the image by selectively erasing the original image.

[Object of the Invention]

The present invention has been made in view of the above circumstances, and an object thereof is to be able to erase an arbitrary portion of a document image to form an image, and to suppress an increase in size of the apparatus. It is an object of the present invention to provide an image forming apparatus which is possible and has excellent operability.

[Outline of Invention]

According to the present invention, for example, an original image is irradiated with spot light, the spot light is moved to specify an erasing range, and the photosensitive drum is irradiated with light corresponding to the specified erasing range to generate an electrostatic latent image or an electrostatic latent image. It erases the charge and forms an image.
In particular, the first and second references are provided at both ends of the platen, and a spot light source that is movable in a direction orthogonal to the moving direction of the scanning means is provided on the side surface of the second reference side of the scanning means. When specifying, the original is set on the second reference side, and when copying, the original is set on the first reference side.

Example of Invention

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

16 and 17 schematically show an image forming apparatus of the present invention, for example, a copying machine. That is, reference numeral 1 is a main body of a copying machine, and an original table (transparent glass) 2 for supporting an original is fixed to the upper surface of the main body 1. This manuscript table 2
First and second fixed scales 2 ₁ and 2 ₂ are provided at both ends in the longitudinal direction as a reference for setting a document. Openable original cover 1 ₁ and the work table 1 ₂ is provided in the further vicinity of the document table 2. The document set on the document table 2 is reciprocated in the direction of arrow a by the optical system including the exposure lamp 4 and the mirrors 5, 6 and 7 along the lower surface of the document table 2 during the reciprocation. It is designed to be exposed and scanned. In this case, the mirrors 6 and 7 move at half the speed of the mirror 5 so as to keep the optical path length constant. The reflected light from the original by the scanning of the optical system, that is, the reflected light from the original by the irradiation of the light from the exposure lamp 4 is reflected by the mirrors 5, 6 and 7 and then passes through the lens block 8 for zooming and further the mirror 9. It is reflected by and is guided to the photoconductor drum 10, and the image of the document is formed on the surface of the photoconductor drum 10.

The photosensitive drum 10 rotates in the direction of arrow c, the surface is first charged by the charging charger 11, and then the image of the original is slit-exposed to form an electrostatic latent image. The toner is attached by the developing device 12 to form a visible image. On the other hand, the paper (image-forming body) P is taken out one by one from the selected upper paper feed cassette 13 or lower paper feed cassette 14 by the feed rollers 15 or 16, and the paper guide path 1
It is guided to the registration roller pair 19 through 7 or 18 and is sent to the transfer portion by this roller pair 19. Here, each of the paper feed cassettes 13 and 14 is
Is detachably provided on the lower right end of the main body 1,
Either one can be selected on the operation panel described later. In addition, each of the above-mentioned paper feed cassettes 13 and 1
4 are cassette size detection switches 60 ₁ and 60, respectively
₂ , the cassette size is detected. The detection switches 60 ₁ and 60 ₂ are composed of a plurality of micro switches that are turned on / off according to the insertion of cassettes of different sizes.

On the other hand, the paper P sent to the transfer section is brought into close contact with the surface of the photoconductor drum 10 at the transfer charger 20, and
The toner image on the photosensitive drum 10 is transferred by the action of the charger 20. The transferred sheet P is peeled from the photoconductor drum 10 by the action of the peeling charger 21, is transported on the transport belt 22, and is sent to the fixing roller pair 23 as a fixing device provided at the end portion thereof. The transferred image is fixed by passing through this. Then, the paper P after fixing is
A pair of paper discharge rollers 24 discharge the paper to a tray 25 outside the main body 1. After the transfer, the photosensitive drum 10 is destaticized by the destaticizing charger 26, and the cleaner 27 removes the residual toner on the surface, and the destaticizing lamp 28 erases the residual image to restore the initial state. ing. Reference numeral 29 is a cooling fan for preventing the temperature inside the main body 1 from rising.

FIG. 18 shows the operation panel 30 provided on the main body 1. 30 ₁ is a copy key for instructing the start of copying, and 30
₂ performs such settings number of copies numeric keypad 30 ₃ display unit for displaying the jamming of each part of the operating state or the paper, 30
₄ upper, cassette selection key for selecting the lower sheet cassette 13, 30 ₅ cassette display unit to display the selected cassette, the magnification setting 30 ₆ to set enlargement copying, the reduction ratio in a predetermined relationship A key, 30 ₇ is a zoom key for continuously setting the enlargement / reduction ratio, 30 ₈ is a display unit for displaying the set magnification, 30 ₉ is a density setting unit for setting the copy density, and 30 _a , 30 _b , 30 _c , 30 _d are operation keys for moving a spot light source, which indicates an erasing position of an original document, which will be described later, 30 _e are position designation keys for inputting coordinate positions indicated by the spot light source, and 30 _f , 30 _g are erasing at designated positions, respectively. It is an erase range designation key for designating a range.

FIG. 19 shows an example of the drive source configuration of each drive section of the copying machine configured as described above, which is configured by the following motors. That is, reference numeral 31 is a lens motor, which is a motor for moving the position of the lens block 8 for varying the magnification. Reference numeral 32 denotes a mirror motor, which is a motor for changing the distance (optical path length) between the mirror 5 and the mirrors 6, 7 for changing the magnification. Three
A scanning motor 3 is a motor for moving the exposure lamp 4, the mirror 5, and the mirrors 6 and 7 for scanning a document. Reference numeral 34 denotes a shutter motor, which is a motor for moving a shutter (not shown) for adjusting the charging width of the charger 11 on the photosensitive drum 10 during zooming. A developing motor 35 is provided in the developing unit 12
It is a motor for driving the developing roller 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 includes the paper feed path 22, the fixing roller pair 23, and the paper discharge roller pair 24.
Is a motor for driving. Reference numeral 38 denotes a paper feeding motor, which is a motor for driving the delivery rollers 15 and 16. A paper feeding motor 39 is a motor for driving the registration roller pair 19. Reference numeral 40 denotes a fan motor, which is a motor for driving the cooling fan 29.

FIG. 20 shows a drive mechanism for reciprocating the optical system. That is, the mirror 5 and the exposure lamp 4 are supported by the first carriage 41 ₁ , and the mirrors 6, 7 are supported by the second carriage 41 ₂ , respectively. These carriages 41 ₁ , 41 ₂ are guided by guide rails 42 ₁ , 42 ₂ . Thus, it can move in parallel in the direction of arrow a. That is, the four-phase pulse motor 33 drives the pulley 43. This is between the pulley 43 and the idle pulley 44 endless belt 45 is stretched over one end of the first carriage 41 ₁ which supports the mirror 5 to the middle portion of the belt 45 is fixed. On the other hand, the rail 42 is attached to the guide portion 46 of the rail 42 ₂ of the second carriage 41 ₂ that supports the mirrors 6 and 7.
_A wire 48 is stretched between two pulleys 47, 47 spaced apart in the two axial directions. One end of the wire 48 is fixed to the fixed portion 49, and the other end is fixed to the fixed portion 49 via a coil spring 50. The first carriage 41 ₁ end in the middle portion of the wire 48 is fixed. Therefore, when the pulse motor 33 rotates, the belt 45 rotates and the first carriage 41 ₁
There moved, the second carriage 41 ₂ also moves with it. In this case, the pulleys 47, 47 to serve the Gado pulley, the second carriage 4 with respect to the first carriage 41 ₁
1 and ₂ move in the same direction at 1/2 speed. The moving directions of the first and second carriages 41 ₁ and 41 ₂ are controlled by switching the rotation direction of the pulse motor 33.

Further, a copyable range corresponding to the designated sheet is displayed on the document table 2. That is, if the paper size designated by the paper selection key 30 ₄ is (P _x , P _y ) and the copy magnification designated by the magnification setting keys 30 ₆ and 30 ₇ is K, the copyable range (x, y) Becomes x = _Px / Ky = _Py / K. Of the copyable range (x, y), the x direction is displayed by the pointers 51 and 52 arranged on the back surface of the document table 2, and the y direction is a scale provided on the upper surface of the first carriage 41 _1. It is designed to be displayed by 53.

The pointers 51 and 52 are, as shown in FIG.
It is provided on a wire 57 that is hung between 4, 55 via a spring 56. The pulley 55 is the motor 5
The motor 58 is driven in accordance with the paper size and the magnification, so that the distance between the policies 51 and 52 can be changed.

The first carriage 41 ₁ by the motor 33 is driven in accordance with the paper size and magnification, it is adapted to move to a predetermined position (home position corresponding to the magnification). When the copying key 30 ₁ is depressed, the first
The carriage 41 ₁ is first moved to the second carriage 41 in _two directions, then the lamp 4 is moved away from the ₂ second carriage 41 is lighted. When the scanning of the document is completed, the lamp 4 is turned off and the first carriage 4
1 ₁ is returned to the home position.

FIG. 22 shows an overall control circuit, which includes a main processor group 71 and first and second sub-processor groups 72 and 73.
Mainly composed of and. Main processor group 71
Is an operation panel 30 and various switches and sensors, for example, a high-voltage transformer 76 that detects an input from an input device 75 such as the cassette size detection switches 60 ₁ and 60 ₂ and drives the various chargers, the discharge lamp 28, and the cleaner. The blade solenoid 27a of 27, the heater 23a of the fixing roller pair 23, the exposure lamp 4, the motors 31 to 40, 58, etc. are controlled to perform the above-described copying operation, the spot light source 131, and the pulse motor 135. , Erase array 150, array driver 16
0, the memory 140 and the like are controlled to erase an unnecessary portion of the original. The spot light source 131, the pulse motor 135, the erasing array 150, and the array driving unit 16
0, the memory 140 will be described later.

Of the above-mentioned motors 31-40, 58, the motors 35, 3
7, 40 and the toner 77 for supplying toner to the developing device 12 are controlled by the main processor group 71 via the motor driver 78, and the motors 31 to 34 and 135 are
Controlled by the first sub-processor group 72 via the pulse motor driver 79, the motors 36, 39, 38, 58 are
It is controlled by the second sub-processor group 73 via the pulse motor driver 80. The exposure lamp 4 is controlled by the main processor group 71 via the lamp regulator 81, and the heater 23 a is controlled by the main processor group 71 via the heater controller 82. Then, a drive / stop command for each motor is sent from the main processor group 71 to the first and second sub-processor groups 72 and 73, and from the first and second sub-processor groups 72 and 73 to the main processor group 71, respectively. A status indicating the drive / stop state of the motor is sent. Further, in the first sub-processor group 72, the motor 31
Position information is input from the position sensor 83 that detects each of the initial positions 34 to 34.

FIG. 23 shows a configuration example of the main processor group 71. That is, reference numeral 91 is a one-chip microcomputer (hereinafter simply referred to as a microcomputer), which performs key input detection of an operation panel (not shown) and various display controls via the input / output port 92. Further, the microcomputer 91 is expanded by input / output ports 93 to 96. A high voltage transformer 76, a motor driver 78, a lamp regulator 81 and other outputs are connected to the input / output port 93, and a size switch for detecting the paper size and other inputs are connected to the input / output port 94. A copy condition setting switch and other inputs are connected to 95. The input / output port 96 is an option.

FIG. 24 shows a configuration example of the first sub-processor group 72. That is, 101 is a microcomputer, which is connected to the main processor group 71. Reference numeral 102 denotes a programmable interval timer for controlling the phase switching interval time of the pulse motor, which counts based on the set value set by the microcomputer 101, and when it counts out, the end pulse is an interrupt line of the microcomputer 101. Output to. A reference clock pulse is input to the timer 102. In addition, in the microcomputer 101,
The position information from the position sensor 83 is input, and the input / output ports 103 and 104 are connected. The motors 31 to 34 and 135 are connected to the input / output port 104 via the pulse motor driver 79. The input / output port 103 is used when outputting the status signal of each pulse motor to the main processor group 71.

FIG. 25 shows a configuration example of the second sub processor group 73. That is, 111 is a microcomputer, which is connected to the main processor group 71. Reference numeral 112 denotes a programmable interval timer for controlling the phase switching interval time of the pulse motor, which counts based on a set value set by the microcomputer 111, and outputs an end pulse when the count out occurs. This end pulse is latched by the latch circuit 113, and its output is supplied to the interrupt line and the input / output port input line of the microcomputer 111. Also, the microcomputer 111 has an input / output port 11
4 is connected to the input / output port 114 via the pulse motor driver 80.
39 and 58 are connected.

FIG. 26 shows a control circuit for the pulse motor, which includes an input / output port 121 (input / output port 1 shown in FIGS. 24 and 25).
(Corresponding to 04, 114) is a pulse motor driver 122
(Corresponding to the pulse motor drivers 79 and 80 in FIG. 22)
Is connected to the pulse motor driver 122 (the pulse motors 31 to 34, 36, 3).
Equivalent to 8, 39, 58, 135) each winding adjustment A, B,
Are connected.

FIG. 27 shows a speed control method for a pulse motor.
Figure (a) shows the speed curve of the pulse motor, and figure (b) shows the phase switching interval. As is clear from this figure, the phase switching interval is long at first, gradually shortened, then becomes evenly spaced, then gradually becomes longer again, and stops. In other words, this shows the slew up and slew down of the pulse motor.
It is about to fall. Note that t ₁ , t _2, ..., T _x indicate the time of the phase switching interval.

Next, the main part of the present invention will be described. Fig. 1 and 2
In the figure, the first carriage 41 ₁ of the second fixed scale 2 ₂ side surface, and, the light is blocked portion of the lamp 4 and the guide shaft 130 is provided along the ramp 4, this guide shaft A spot light source 131 as a means for instructing an erasing range of a document is movably provided at 130. This spot light source 131, as shown in FIG.
It is composed of light emitting elements 132 and 133 such as light emitting diodes or lamps provided facing the document table 2, and the light generated by the light emitting element 132 is applied to the document table 2 as spot light having a diameter d by the lens 133. It is supposed to be done. The spot light has a brightness that allows the document G set on the document table 2 to have a thickness of, for example, a postcard, to pass through. Further, the spot light source 131 is connected to a timing belt (toothed belt) 134 arranged along the guide shaft 130. The timing belt 134 is stretched around a pulley 136 and a driven pulley 137 provided on the rotation shaft of the pulse motor 135. Accordingly, the spot light source 131 by the pulse motor 135 is rotated is moved in a direction perpendicular to the first carriage 41 _first scan direction. Further, the first carriage 4 located at the end of the guide shaft 130 on the pulse motor 135 side.
The 1 ₁ is provided with a position sensor 138 consisting of a micro switch for detecting the initial position of the spot light source 131, for example, if the spot light source 131 is moved, first, the initial spot light source 131 is in contact with the position sensor 138 The position is detected.

Meanwhile, to specify the erase range of the original by using the spot light source 131, the document G as shown in Figure 3, is set copied side along the second fixed scale 2 ₂ as upward. At this time, the first carriage 41 ₁ corresponding to a predetermined reproduction scale, is stopped at a position indicating the copy range. Further, the dimension W between the _first and second fixed scales 2 ₁ and 2 ₂ is generally slightly larger than the maximum document size. For example, assuming that the maximum document size is A3, the long side of this document is 420 mm, so the first and second fixed scales 2
_1, the dimension W between _{2 2} becomes W = 420 + alpha. If the original is A4, it is half of A3, so A
When the long side of the four originals is l ₀ = 210, the dimension W is W = 2l ₀ + α. Thus, the dimension W is set with a margin of at least the distance α. This is because _{the 1} first carriage 41 is operated from a stopped state, which requires a certain distance to a stable speed.

Further, it provided the spot light source 131 to the first second fixed scale 2 ₂ side of the carriage 41 _1, and, when specifying the erasing range by setting along the document on the second fixed scale 2 _2, the copying machine main body It is possible to suppress the enlargement of the shape of No. 1 and specify the erasing range up to the maximum document size. That is, if you try to specify the erase range in the first fixed scale 2 ₁ side, as shown in FIG. 4, the spot light source 131
Is caused by the distance l _{b, in} which the optical axis cannot reach the edge of the first fixed scale 2 ₁ . That is, the first carriage 41 ₁ is moved from the edge intersections of the first fixed scale 2 ₁ between the optical axis and the platen 2 of the exposure lamp 4 when copying to the position of the distance l _a, the exposure lamp 4 from the position There is adapted to be moved in a direction away from the first fixed scale 2 ₁ is turned. Here, the distance l _a is the minimum distance required to constant speed from as stopped _{state 1} the first carriage 41 previously described. Therefore, when to move the optical axis of the spot light source 131 to the first fixed scale 2 _first edge, in which copying speed movement distance of the first carriage 41 ₁ is extended is reduced.
Moreover, since the many second moving distance of the carriage 41 ₂ interlocked ₁ and the first carriage 41, the distance l _c from the first fixed scale 2 _first edge to the side surface of the main body of the copying machine 1 is long, the body 1 This leads to an increase in the size of.

On the other hand, if to specify the erase range by setting a document to the second fixed scale 2 ₂ side as shown in FIG. 3, as shown in FIG. 5, a second fixed scale light axis of the spot light source 131 2 _Since it is possible to move to the edge of No. ₂ , the unspecified range can be minimized and the maximum document size can be specified.

Next, with reference to FIG. 3 and FIGS. 6 to 8, the operation of designating the erasure range of the original by the spot light source 131 will be described.

As shown in FIG. 3, when a document is set and the operation keys 30a to 30d described above are operated, the spot light source 131 is moved. That is, the operation keys 30b, pressing the 30d, the motor 33 is driven, the first carriage 41 ₁ and spot light source 131 (arrow y direction shown in FIG. 3) scanning direction
Be moved to. When the operation keys 30g and 30c are pressed, the motor 135 is driven, and the spot light source 131 is moved in the direction orthogonal to the scanning direction (arrow x direction shown in FIG. 3). The operator operates the operation key 30 _a to 30 _d while viewing the spot light transmitted through the document G, for example, 6
The position designation key _30e is pressed with the spot light moved to point S ₁ on the document G shown in FIG. Then, the coordinate position designated by S ₁ is stored in the main processor group 71 shown in FIG. Similarly with moving the spot light S ₂ points on the original G in position designation key 30 _e to Osuru, position of S ₂ points is stored in the main processor group 71. The position of this spot light is, for example, the pulse motor 33,
It can be detected by counting the number of driving pulses of 135. After that, when the erase range designation key _30f is pressed, a rectangular area (shown by diagonal lines) having diagonal points S ₁ and S ₂ is designated as the erase range as shown in FIG. 6 (a). Further, as shown in FIG. 6 (b), S ₃ points and S _{4 of the} document G are
When a point is specified and the erase range specification key 30 _g is pressed, S ₃ ,
A portion other than a square having S ₄ as a diagonal point is designated as an erasing range. Thus, the document G deletion range is specified, flipped in the y-direction as shown in FIG. 7 at the time of copying, is set along the first fixed scale 2 _1.

Meanwhile, pressing the erase range designation key 30 _f, 30 _g, calculated in the main processor group 71 is performed based on the specified two points located, a high level signal to the erasing range portion in the memory 140 "1 ", And the low level signal" 0 "is stored in the other portions. That is, this memory 14
In 0, for example, the capacitance in each column direction is substantially equal to the movement distance of the spot light source 131 in the x direction divided by the position resolution in the x direction, and the capacitance in each row direction is the movement distance of the spot light source 131 in the y direction divided by the position resolution in the y direction. It is constituted by a RAM substantially matched with, and in the case of FIG. 6A, as shown in FIG. 8A by the data supplied from the main processor group 71, as shown in FIG. In the case of b), as shown in FIG. 8 (b), the high level signal is stored at the address corresponding to the shaded portion, and the low level signal is stored at the other addresses. In this case, when as copying of the above-described original is turned over, because it is set along the first fixed scale 2 _1, mainly the y-direction central portion designated deletion range is the y direction in the document table 2 position Has been returned as. Therefore, the y-direction storage address of the high level signal and the low level signal is also converted correspondingly, and a predetermined signal is stored according to the converted address.

On the other hand, as shown in FIG. 9, an erasing array 150 as an erasing means is provided in proximity to the photosensitive drum 10, for example, between the charger 11 and the exposure section Ph. This erase array 15
0 indicates the photoconductor drum 10 as shown in FIGS.
A plurality of light shielding cells 151 in a direction orthogonal to the rotation direction of the
Are arranged, and the 12th cell is arranged inside each of these cells 151.
As shown in FIGS. (A) and (b), a light emitting element 152 including, for example, a light emitting diode is provided. Also. Each cell 151
The light emitting element 15 is provided in the opening facing the photoconductor drum 10 of
3 is provided. The number of light emitting elements arranged in the erasing array 150 is equal to the capacity of the memory 140 in the column direction. Here, when the distance between the light emitting elements 152 is P and the number is N, the total length of the erasing array 150 is Q = N × P.

The erase array 150 is driven by the array driver 160 described above. As shown in FIG. 13, the array driving unit 160 has a shift register 161 having the same number of bits as the column direction of the memory 140, and a store register 16 for holding the contents of the shift register 161.
2, on the respective output signals of the store register 162 is constituted by a switch circuit 164 comprising a plurality of switching elements 163 are turned off controlled, the movable contact piece 163 _a of the switch elements 163 is grounded, the fixed contact 163 _b is connected to each cathode of a light emitting element (light emitting diode) 152 that constitutes the erasing array 150. The anode of each of the light emitting elements 152 is connected to the power supply _Vcc through the current limiting resistor R.

Thus, to specify the erase range of document as described above, after setting along the first fixed scale 2 ₁ Turn the document, close the document cover 1 _1, pressing the copy key 30 _1,
First, as shown in FIG. 14, the first carriage 41 ₁ is first moved from the erasing range designation end position D _{1 in} the first fixed scale 2 ₁ direction. After that, the first carriage 41 ₁ is moved in the direction away from the first fixed scale 2 _1, and the photoconductor drum 10 is operated accordingly. When these are operated, the memory 140 is moved in the row direction (shown in FIG. 8).
The data for one column is sequentially read. The read data D ₁ is transferred to the shift register 161 of the array driver 160 by the clock signal CLK as shown in FIG. After one column of data has been transferred to the shift register 161, when the charged portion of the photosensitive drum 10 reaches the erasing array 150, the main processor group 71 outputs a latch signal LTH, and shifts according to this signal. The contents of the register 161 are supplied to the store register 162. That is, since the erasing array 150 is disposed between the charger 11 and the exposure unit Ph, the data for one column output from the memory 140 is, for example, the angle θ ₁ between the erasing array 150 and the exposure unit Ph. Therefore, assuming that the photosensitive drum 10 is rotating at the angular velocity ω, the output timing of the latch signal LTH is controlled so that it is supplied to the store register 162 before θ ₁ / ω. In addition, the switch circuit 16
Each switch element 163 of No. 4 has this store register 162.
Is controlled by each output signal of. That is, when the output signal of the store register 162 is high level, it is turned on, and when it is low level, it is turned off. As a result, the light emitting element 152 connected to each switch element 163.
Is turned on when the switch element 163 is on, and turned off when the switch element 163 is off. Therefore, of the charged portion of the photoconductor drum 10, the portion where the light emitting element 152 is turned on is discharged, and the removed portion is not exposed to an electrostatic latent image even after being exposed to erase the original image. It has been broken.
Thereafter, in the same manner, the data in the memory 140 is read out column by column and the image is erased. When such copying operation is completed, the first carriage 41 ₁ as shown in FIG. 14, is stopped at the position D ₂ showing the image forming range.

According to the above-described embodiment, unnecessary portions of the original can be designated and erased, which is convenient for editing the copied image.

Further, provided the spot light source 131 to the first second fixed scale 2 ₂ side of the carriage 41 _1, and, when specifying the deletion range, so that set along the document on the second fixed scale 2 _2. Therefore, it is possible to specify the erasing range up to the maximum document size, and it is possible to prevent the shape of the copying machine main body 1 from increasing in size.

Furthermore, to specify the erase range second scale 2 ₂ side, first
Because the document handling operation so that it becomes possible copying by setting Turn the document to the scale 2 ₁ side is natural, a transfer from the erasing range designating the copy, the operability with a setting error of the document can be prevented It is excellent.

Further, when the erasing range is designated, the copying surface of the document is set on the document table 2 as a table, and the document can be designated by the spot light passing through the document in this state, so that the designation operation is easy. It is easy to confirm the erase range.

Furthermore, since the provided spot light source 131 to the first carriage 41 _1, can be effectively used space, it is possible to suppress the size of the apparatus.

The present invention is not limited to the above embodiment.
For example, the arranging position of the erasing array 150 is not limited to the position between the charger 11 and the exposure unit Ph shown in FIG. 9, but may be formed between the exposure unit Ph and the developing unit 12 as shown in FIG. It is also possible to delete the formed electrostatic latent image according to the designation.

Also, the capacity of the memory 140 can be changed as required.

Of course, various modifications can be made without departing from the spirit of the invention.

〔The invention's effect〕

As described above in detail, according to the present invention, an image can be formed by erasing an arbitrary portion of a document image, and further, the first and second references are provided on the document table, and the instruction means is provided. The scanning means is provided so as to be movable on the second reference side, and when the position of the original is designated, the original is placed on the original table along the second reference. Therefore, it is possible to point at any position of the original within the scanning range of the scanning unit,
It is possible to prevent the device from becoming large.

Further, when the first and second points are designated on the original, the erasing area is defined by these two points, so that the designation operation is easy.

[Brief description of drawings]

1 to 14 show an embodiment of the main part of an image forming apparatus according to the present invention. FIG. 1 is a perspective view of the main part showing a spot light source, and FIG. 2 is a spot light source. FIG. 3 is a side sectional view of a main portion, FIG. 3 is a plan view showing a set state of a document, FIGS. 4 and 5 are side sectional views of the main portion for explaining the arrangement of spot light sources, and FIG. FIG. 7 is a plan view showing a document erasing range designation operation using a spot light source, FIG. 7 is a perspective view of a main part shown for explaining a document reversing direction, and FIG. 8 is a memory content. FIG. 9 is a side sectional view of an essential portion showing the arrangement of the erasing array, FIGS. 10 and 11 show the relationship between the erasing array and the photosensitive drum, and FIG. FIG. 11 is a perspective view showing only a main part, FIG. 11 is a front view showing only a main part, and FIG.
FIG. 2 shows the structure of the erase array. FIG. 2 (a) is a side sectional view, FIG. 2 (b) is a partially cutaway front view, and FIG.
3 figures circuit diagram showing a configuration of an array driver, FIG. 14 is a plan view for explaining the first carriage 41 _first operation, FIG. 15 of the main part showing another arrangement example of the erase array Side sectional views, FIGS. 16 and 17 show the structure of the image forming apparatus. FIG. 16 is a schematic perspective view, FIG. 17 is a side sectional view, and FIG. 18 is a plan view showing the structure of an operation panel. FIG. 19 is a perspective view showing the structure of a drive unit, FIG. 20 is a perspective view schematically showing a drive mechanism of an optical system, and FIG. 21 is a perspective view schematically showing a drive mechanism of a pointer. FIG. 23 is a block diagram showing the overall control circuit, FIG. 23 is a block diagram of a main processor group, FIG. 24 is a block diagram of a first sub-processor group, and FIG.
FIG. 5 is a block diagram of the second sub-processor group, FIG. 26 is a schematic block diagram showing a control circuit of the pulse motor, and FIG. 27 is a diagram for explaining a speed control method of the pulse motor. 1 ... Copier main body, 2 ... Original plate, 2 ₁ , 2 ₂ ... First and second fixed scales, 10 ... Photosensitive drum, 30 _a
~ 30 _d ... operation key, 30 _c ... position designation key, 30
_f , 30 _g ... Erase range designation key, 33 ... Scan motor, 41 ₁ ... First carriage, 71 ... Main processor group, 131 ... Spot light source, 132 ... Light emitting element, 133 ... Lens, 135 ... Pulse motor, 15
0 erasing array, 152 ... Light emitting element, 153 ... Lens, 160 ... Array driving unit, 140 ... Memory, P ...
… Paper, Ph… Exposure part.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-56-109364 (JP, A) JP-A-59-133567 (JP, A) JP-A-56-81865 (JP, A) JP-A-59- 88754 (JP, A) JP 58-43480 (JP, A) JP 61-105571 (JP, A) JP 61-112172 (JP, A) JP 61-151574 (JP, A) JP-A-61-156072 (JP, A) JP-A-60-123834 (JP, A) Actual development 59-151238 (JP, U)

Claims (3)

[Claims] 1. A document table on which a document is placed, a first reference which is provided at one end of the document table and defines a document placement position during image formation, and at the other end of the document table. A second reference is provided, which defines the placement position of the original when the area is designated, and an exposure lamp is placed, and the exposure lamp is turned on while moving from the first reference to the second reference direction. As a result, the document placed on the document table is exposed and scanned in accordance with the first reference, and scanning means for guiding light corresponding to the document image onto the image carrier to form a latent image, and scanning means on the image carrier are provided. An image forming unit that develops the formed latent image to form an image, and is provided on the scanning unit and at a position separated from the exposure lamp on the second reference side by a predetermined distance. It is movable in a direction perpendicular to the scanning direction and is movable in the second direction.
Instructing means for instructing an arbitrary position on the original by irradiating the original placed on the original table with a spot light having a predetermined diameter according to the reference, and a movement for moving the instructing means. Means, a position designating means for inputting position information on the document designated by the designating means, the designating means is moved by the moving means to designate a point on the document, and the position designating means Setting means for designating the first point and the second point by inputting position information of the designated point, and for setting an area defined by the designated first point and the second point. A plurality of light emitting elements are arranged facing the image carrier, and when the image is formed on the image carrier, the light emitting elements are selectively turned on in accordance with a region set by the setting unit. By the front An image forming apparatus, comprising: an erasing unit that prevents an image of the document corresponding to the inside or the outside of the recording area from being formed on the image carrier. 2. The image forming apparatus according to claim 1, wherein the instructing means comprises a light emitting element and a lens for irradiating the original surface with spot light. 3. The erasing means is arranged in the vicinity of the image bearing member along the longitudinal direction of the image bearing member, the computing means corresponding to the position of the document scanned by the area set by the setting member. The image forming apparatus according to claim 1, comprising a plurality of light emitting elements whose lighting is controlled by an output signal of the calculation unit.