JPS62145267A - Image forming device - Google Patents

Abstract

PURPOSE:To transmit light through all originals and to specify an erasure range without fail by using a light emitting diode with ultra high brightness as an erasing means. CONSTITUTION:Light irradiated by a spot light source 131 forms a spot with a diameter (d) on an original platen 2 and this spot light has ultra high brightness of >=1,500millicandela and is transmitted through an original almost as thick as a name card or postcard, or a stack of 10 originals of 64kg set on the original platen 2, i.e. any kinds of original which is used normally. An operator operates operation keys 30a-30d over a look at the spot light transmitted through the original G and then presses a position specifying key 30e, so that a specified coordinate position is stored in a main processor group. Then when an erasure range specifying key 30f is pressed, a rectangular area (hatched) having points S1 and S2 as diagonal points is specified as the erasure range.

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 copy frame.

[Technical background of the invention and its problems]

As is well known, a copying machine has the function of copying an original image directly onto a sheet of paper, or enlarging or reducing the original image and making a copy. Furthermore, recently, a device has been developed and put into practical use that erases a predetermined range of images (partial images) of a document before copying.

By the way, as a method of specifying the area to be erased, a light source for specifying the erasure area provided at the bottom of the document table is moved and illuminated on the original, in other words, the transmitted light is used to specify the area to be erased. It is designed to do this.

However, the brightness of the above light source is 200~3
Since 0.00 mm candela was used, the light could barely pass through one sheet of original (64g paper) as thick as copy paper, and it was difficult to transmit light through thick originals such as business cards and postcards. There was a problem in that it was not possible to specify the erasing range.

[Purpose of the invention]

This invention has been made in view of the above circumstances, and its purpose is to provide an image forming apparatus that can transmit light to all documents and that can always specify the erasing range. It is about providing.

[Summary of the invention]

In this invention, a light emitting diode with ultra-high brightness of 1,500 millicandela or more is used as the erasing means.

[Embodiments of the invention]

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

FIGS. 11 and 12 schematically show an image forming apparatus of the present invention, such as a copying machine. A document table (transparent glass) 2 for supporting a document is fixed to the top surface of the copying machine main body 1. Fixed scales 21 and 22 are provided at both ends of the document table 2 to serve as a reference for setting the document, and furthermore, a document cover 11 and a work table 12 which can be opened and closed are provided near the document table 2. Then, the above document table 2
The original placed on the exposure lamp 4, mirror 5.6.7
An optical system consisting of the following is reciprocated along the lower surface of the document table 2 in the direction of arrow a, thereby performing exposure scanning. In this case, mirror 6.7 is moved at 1/2 the speed of mirror 5 so as to maintain the light exposure length. The light reflected from the original by the scanning of the optical system, that is, the exposure lamp 4
The reflected light from the original due to the light irradiation is reflected by the mirrors 5, 6, and 5.
7, passes through a variable magnification lens block 8, is further reflected by a mirror 9, and is directed onto a photoreceptor drum 10.
The image of the document is formed on the surface of the photosensitive drum 10.

The photosensitive drum 10 is rotated in the direction of arrow C in the figure, and first, ? ! The surface is charged by the charging device 11. When this pattern image is exposed to slit light, an electrostatic latent image is formed on the surface. This electrostatic latent image is made visible by applying toner by the developer 12.

On the other hand, the paper (transfer material) 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 15 or 16, and the taken out paper is taken out from the paper guide path 17 or 18 and is guided to a pair of registration rollers 19, and guided to a transfer section by this pair of registration rollers 19. Here, the paper feed 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 601 and 602, respectively. The cassette size detection switches 601 and 602 are composed of a plurality of microswitches that are turned on and off according to the insertion of cassettes of different sizes.

The MP sent to the transfer section is brought into close contact with the surface of the photoreceptor drum 10 at the transfer charger 20, and
The toner image on the photoreceptor drum 10 is transferred by the action of 0. The transferred paper P is electrostatically peeled off from the photosensitive drum 10 by the action of a peeling charger 21, and is sent by a conveyor belt 22 to a fixing roller 23 as a fixing device provided at the end thereof. The transferred image is fixed by passing through this, and the fixed paper P is discharged to a tray 25 outside the main body 1 by a pair of paper discharge rollers 24 . Further, the photoreceptor drum 10 after the transfer is transferred to a charger 2 for removing static electricity.
6, residual toner on the surface is removed by a cleaner 27, and afterimages are erased by a static elimination lamp 28, so that the initial state is restored. Note that 29 is a cooling fan for preventing the temperature inside the main body 1 from rising.

FIG. 13 shows the operation panel 30 provided on the main body 1. 301 is a copy key for commanding the start of copying; 30
2 is a numeric keypad for setting the number of copies, etc.; 303 is a display unit for displaying the operating status of each part and paper jams; and 304
30s is a cassette selection key for selecting the upper and lower paper feed cassettes 13 and 14; 30s is a cassette display section for displaying the selected cassette; 306 is a magnification setting key for setting the copy enlargement and reduction magnification in a predetermined relationship; 307 30a is a display section that displays the set magnification, 30a is a density setting section that sets copy density, and 30a, 30b, 30c, and 30d are document erasers that will be described later. An operation key for moving the spot light source indicating the position, a position designation key 30e for inputting the coordinate position indicated by the spot light source, and erasure range designation keys 30f and 300 for designating the erasure range at each designated position.

FIG. 14 shows an example of the drive source configuration of each drive unit 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 for performing magnification change. Reference numeral 32 denotes a mirror motor, which connects the mirror 5 and mirrors 6 and 7 for variable magnification.
This is a motor for changing the distance (optical path length) between the A scanning motor 33 is a motor for moving the exposure lamp 4, the mirror 5, and 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. A paper feeding motor 39 is a motor for driving the registration roller pair 19. A fan motor 40 is a motor for driving the cooling fan 29.

FIG. 15 shows a drive mechanism for reciprocating the optical system. That is, the mirror 5 and the exposure lamp 4
is supported by a first carriage 411, and mirror 6.7 is supported by a second carriage 422, respectively, and these carriages 411, 412 are guided by guide rails 421, 422 and are movable in parallel in the direction of arrow a. Also, 4
The phase pulse motor 33 drives a 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,.

Two pulleys 47.47 are rotatably provided in the guide section 46 of the second carriage 422 that supports the mirror 6.7, spaced apart in the axial direction of the rail 422, and a wire is connected between these pulleys 47.47. 48 is hanging. One end of this wire 48 is fixed to a fixed part 49, and the other end is fixed to the fixed 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, by rotating the pulse motor 33, the belt 45 rotates and the first carriage 411 is moved, and accordingly, the second carriage 411 is moved.
Carriage 422 is also moved.

At this time, since the pulleys 47 and 47 serve as movable pulleys, the second carriage 422
are moved in the same direction at 1/2 the speed. Furthermore, first,
The direction of movement of the second carriages 411, 412 is controlled by switching the direction of rotation of the pulse motor 33.

Further, on the document table 2, a copyable range corresponding to the specified paper is displayed. That is, the cassette selection key 304
Let the paper size specified by (Px, Py) be,
If the copy magnification specified by the magnification setting keys 30a and 307 is K, the copyable range (X, l is [x-Px
/KJ.

rV-PV/Kl. This copyable range (X, y)
In the X direction, a pointer 51 provided on the back side of the document table 2
．． 52, and the y direction is indicated by a scale 53 provided on the upper surface of the first carriage 411.
and the distance between the fixed scales 21.

As shown in FIG. 16, the above-mentioned pointers 51 and 52
．． 55 via a spring 56. The pulley 55 is a motor 58
This motor 58
is driven in accordance with the determined copyable range in the X direction, thereby changing the distance between the hands 51 and 52.

Further, the first carriage 411 is moved to a predetermined position (home position according to the magnification) by driving the motor 33 according to the paper size and magnification. When the copy key 301 is pressed, the first 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 41
1 is returned to the home position.

FIG. 17 shows the overall control circuit.

The main processor group 71 includes a high-voltage transformer 76 that detects inputs from an input device 75 such as the operation panel 30clj 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, the blade solenoid 27a of the cleaner 27, and the heater 23a of the fixing roller pair 23.
, the exposure lamp 4, and each of the motors 31-40.
58, etc. to perform the above-mentioned copying operation, and also control the spot light source 131, pulse motor 135, memory 1
40. It controls the erasing array 150, array drive unit 160, etc. to detect the set position of the original and perform operations to erase unnecessary portions of the original. In addition, a spot light source 13, a pulse motor 135, and an erasing array 1501
The array driver 160 and memory 140 will be described later.

Among the above motors 31 to 40.58, motor 35.37
．． A toner motor 77 that supplies toner to the developing unit 40 and the developing device 12 is controlled by the main processor group 71 via a motor driver 78.
are controlled by the first sub-processor group 72 via a pulse motor driver 79, and the motors 36, 39, 38, 58
is controlled by the second sub-processor group 73 via the pulse motor driver 80. Further, the exposure lamp 4 is controlled by the main processor group 71 via the lamp regulator 81, and the heater 23a is controlled by the main processor group 71 via the heater control section 82. The main processor group 71 to the first and second sub-processor groups 72.7
Drive and stop commands for each motor are sent to the first motor. Second
From sub-processor group 72 and 73 to main processor group 7
1, a status signal indicating the driving or stopping state of each motor is sent. The first sub-processor group 72 also includes a position sensor 83 that detects each initial position of the motors 31 to 34.
Location information has been entered from.

FIG. 18 shows an example of the configuration of the main processor group 71. One-chip microcomputer 91 (hereinafter referred to as
The microcomputer (simply referred to as a microcomputer) detects human power on keys on an operation panel (not shown) and performs various display controls via an input/output board 92.

Further, the microcomputer 91 is expanded by input/output ports 93-96. A high voltage transformer 76, a motor driver 78, a lamp regulator 81, and other outputs are connected to the input/output capo 1-93, and a size switch for detecting paper size and other inputs are connected to the input/output boat 94. A copy condition setting switch and other inputs are connected to the output port 95. Note that the input/output port 96 is an option.

FIG. 19 shows an example of the configuration of the first sub-processor group 72. The microcomputer 101 is the main processor group 7
1 is connected. Programmable interval
The timer 102 controls the phase switching interval time of the pulse motor. When a set value is set from the microcomputer 101, the timer 102 starts counting reference clock pulses based on the setting value. When the timer 102 has counted out, the end pulse is sent to the microcomputer 101. It is configured to output to the interrupt line. The microcomputer 101 also includes the position sensor 8.
Position information from 3 is input, and input/output boats 103 and 104 are connected. The input/output boat 104 is connected to the motors 31 to 34.135 via the pulse motor driver 79. still,
The input/output board 103 is used, for example, when outputting status signals of each pulse motor to the main processor group 71.

FIG. 20 shows the configuration of the second sub-processor group 73. The microcomputer 111 is connected to the main processor group 71
is connected to. The programmable interval timer 112 controls the phase switching interval time of the pulse motor, and when a set value is set from the microcomputer 111, it starts counting reference clock pulses based on it, and when the count is out, it starts counting the end pulse. It is designed to be output. This end pulse is latched by the latch circuit 113, and its output is supplied to the interrupt line of the microcomputer 111 and the input/output port input line. Further, an input/output boat 114 is connected to the microcomputer 111, and this input/output boat 114 is connected to the pulse motor driver 8.
Motors 36.38.39.58 are connected via 0.

Figure 21 shows the control circuit of the pulse motor.
The input/output boat 121 (corresponding to the input/output boats 104 and 114 in FIGS. 19 and 20) has a pulse motor driver 1.
22 (corresponding to the pulse motor driver 79.80 in FIG. 17) is connected to the pulse motor driver 122.
6.38.39.58.135) each winding A.

B, A, and B are connected.

FIG. 22 shows a method for controlling the speed of a pulse motor. FIG. 3(a) shows the speed curve of the pulse motor, and FIG. 1(b) shows the phase switching interval.

As is clear from this figure, the phase switching interval is long at the beginning;
They gradually shorten, then become evenly spaced, then gradually lengthen again, and then 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. Furthermore, tl.

t2...tx indicates the time of the phase switching interval.

Next, the document image erasing means as the gist of the present invention will be explained. 1 and 2, a guide shaft 130 is provided in the first carriage 411 along the lamp 4 in a portion where the light of the lamp 4 is blocked. A spot light source 131 is movably provided on the guide shaft 130 as a means for indicating the erasing range of the original. This spot light source j131 is as shown in FIGS. 2(a) and (b).
The spot light source 131 is arranged so that its optical axis is perpendicular to the document table 2. This spot light m131 is generated by a light emitting element 131 such as a light emitting diode (LED) or a lamp.
a, and a lens 131b that guides the light generated by the light emitting element 131a toward the document table 2.

The lighting signal for the light emitting element 131a is supplied from the main processor group 71. The light emitted from the spot light source 131 is irradiated onto the document table 2 as a spot light having a diameter d, as shown in FIG.
1 that can transmit all documents that are normally used, including originals as thick as postcards and 10 sheets of 640 paper.
It has an ultra-high brightness of over 500 millicandela.

Further, the spot light source 131 is connected to a timing belt (toothed belt) 134 disposed along the guide shaft 130. This timing belt 134 is passed between a pulley 136 provided on the rotating shaft of a pulse motor 135 and a driven pulley 137. Therefore, by rotating the pulse motor 135, the spot light source 1
31 is moved in a direction perpendicular to the scanning direction of the first carriage 411. In addition, the pulse motor 1 of the guide shaft 130
The first carriage 41 located at the end of the 35 side! is provided with a position sensor 138 consisting of a microswitch that detects the initial position of the spotlight [131]. For example, when the spot light source 131 is moved, the spot light source 131 first comes into contact with the position sensor 138 and its initial position is detected.

Next, using FIGS. 3 to 5, the spot light source 13
A method of specifying the erasing range of a document using 1 will be explained. When specifying the erasing range of a document, the document G is set on the fixed scale 22 side with the copy side facing up, as shown in FIG. In this state, the operation keys 30a~
When 30CI is operated, the spot light source is moved with the light emitting element 731a turned on. That is, the operation key 30
b and 30d, the motor 33 is driven and the first carriage 411 and spot light #1131 are moved in the scanning direction (
(in the direction of arrow X shown in FIG. 3).

Also, when the operation keys 30a and 30c are pressed, the motor 135
is driven, and the spot light source 131 is moved in a direction perpendicular to the scanning direction (direction of arrow X shown in FIG. 3).

The operator operates the operation keys 30a to 30d while visually observing the spotlight transmitted through the document G, and presses the position designation key 30e after moving the spotlight to point S1 on the original IG shown in FIG. 4(a), for example. Press.

Then, the coordinate position specified by this Sl is stored in the main processor group 71 shown in FIG.

Similarly, when the position designation key 30e is pressed with the spotlight moved to 82 points on the original IG, the positions of the 82 points are stored in the main processor group 71. The position of this spot light can be detected, for example, by counting the number of drive pulses of the pulse motor 33.135. After this, Erasure V! When the enclosure designation key 30f is pressed, as shown in FIG. 4(a), S1 is pressed.

A rectangular area (indicated by diagonal lines) with 82 points as diagonal points is designated as the erasing range. Also, as shown in FIG. 4(b), if you specify points 83 and 84 on the original G and press the erase range designation key 3C1, the area other than the square with the diagonal point S3.34 will be set as the erase range. It is specified.

In this way, when the erasure range designation keys 30f and 300 are pressed, the main processor group 71 performs calculations based on the positions of the two designated points and the copy magnification, and the memory 140
A high level signal jl1## is stored in the erase range portion, and a low level signal ITOIT is stored in the other portions. That is, this memory 140 is constituted by, for example, a RAM whose capacity in each column direction is approximately equal to the movement distance of the spotlight 1l 1131 in the X direction divided by the position resolution in the y and X directions, and by the data supplied from the main processor group 71, In the case of Fig. 4 (a>), as shown in Fig. 5 (a), and in the case of Fig. 4 (b), as shown in Fig. 5 (b), the address corresponding to the shaded part High level signals are stored at addresses other than those, and low level signals are stored at other addresses.

The original G, whose erasing range has been designated as described above, is reversed in the X direction shown in FIG. Ru. Therefore, in this state, the original image and the erased data stored in the memory 140 are associated with each other.

On the other hand, as shown in FIG. 6, an erasing array 150 serving as erasing means is provided close to the photosensitive drum 10, for example, between the charger 11 and the exposure section Ph. As shown in FIGS. 7 and 8, this erasing array 150 is arranged on the photosensitive drum 10.
A plurality of light shielding cells 151 are arranged in a direction perpendicular to the rotation direction of the
are arranged, and inside each of these light-shielding cells 151, a light emitting element 152 made of, for example, a light emitting diode is provided as shown in FIGS. 9(a) and 9(b).

Furthermore, a lens 153 is provided in the opening of each cell 151 facing the photoreceptor drum 10 to focus the light from the light emitting element 152 onto the surface of the photoreceptor drum 10 . The number of light emitting elements arranged in this erasing array 150 matches, for example, the capacity of the memory 140 in the column direction. Here, if the distance between the light emitting elements 152 is P and the number of elements is N, the total length of the erasing array 150 is Q-NXP.

The erase array 150 is driven by the array driver 160 described above. As shown in FIG. 10, this array driving section 160 includes a shift register 161 having the same number of bits as the number of bits in the column direction of the memory 140, and a store register 16 in which the contents of this shift register 161 are held.
2. It is constituted by a switch circuit 164 consisting of a plurality of switch elements 163 that are controlled on and off by each output signal of this door register 162, and the movable contact pieces 163a of these switch elements 163 are grounded, and the fixed contacts 163b are connected to each cathode of the light emitting elements 152 constituting the erasing array 150, respectively. The anode of each of these light emitting elements 152 is connected to the power supply VCC through a current limiting resistor R, respectively.

After specifying the erase range of the original as described above, when the original cover 11 is closed and the copy key 301 is pressed, the first carriage 411 and the photosensitive drum 10 are operated, and the memory 140 is read in the row direction. Data for one column (as shown in FIG. 5) is sequentially read out. This read data D! is transferred to the shift register 161 of the array driver 160 by the clock signal CLK.

After one column of data is transferred to the shift register 161, the charged portion of the photoreceptor drum 10 is transferred to the erase array 15.
When the value reaches 0, the main processor group 71 outputs a latch signal LTH, and the data stored in the shift register 161 is supplied to the store register 162 in response to this signal. That is, the erase array 150 includes the charger 11 and the exposure section ph.
For example, one column of data output from the memory 140 is arranged between the erase array 150 and the erase array 150.
If the angle of the exposure section Ph is θl and the photosensitive drum 1o is rotating at each speed, the latch signal LTH is set so that it is supplied to the store register 162 before θ1/ω.
output timing is controlled.

Each switch element 163 of the switch circuit 164 is controlled by the output signal of the store register 162. That is, when the output level 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 elements 152 connected to each switch element 163 are turned on when the switch element 163 is on, and are turned off when the switch element 163 is off. Therefore, among the charged parts of the photoreceptor drum 10, the part where the light emitting element 152 is turned on is charge-free, and even if the charge-free part is exposed afterwards, no electrostatic latent image is formed, and the original image is not erased. It means that it was done. Thereafter, the data in the memory 40 is read out one column at a time in the same manner, and the image is erased.

As mentioned above, since the spot light from the spot light source 131a has an ultra-high brightness of 1500 millicandela or more,
A business card, a document as thick as a postcard, placed on the document table 2,
It is possible to see through a document made of 10 sheets of 640 paper, that is, all documents that are normally used, and it is possible to specify the erasing range even for a document as thick as 100 ml.

Note that this invention is not limited to the above embodiments.

For example, the arrangement position of the erasing array 150 is not limited to that shown in FIG. 6, but as shown in FIG. It is also possible to configure the data to be erased by

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide an image forming apparatus that can transmit light to all original documents and can always specify an erasing range.

[Brief explanation of drawings]

The drawings show an embodiment of an image forming apparatus according to the present invention, and FIG. 1 is a perspective view of a main part showing a spot light source, and FIG. 2(a) [)) is a main part showing a spot light source. FIGS. 3 and 4 are a side sectional view, and FIGS. 3 and 4 are plan views, respectively, for explaining the operation of specifying the erasing range of an original using a spot light source. FIGS. Figure 6 is a side sectional view of the main parts showing the arrangement of the erasing array, Figures 7 and 8'' respectively show the relationship between the erasing array and the photosensitive drum, and Figure 7 is a perspective view showing only the main parts. 8 is a front view showing only the main parts, FIG. 9 shows the configuration of the erasing array, and FIG. 8(a) is a side sectional view,
FIG. 10 is a circuit diagram showing the structure of the array driving section, FIG. 11 is a circuit diagram showing the structure of the image forming apparatus, and FIG. Fig. 11 is an external perspective view, Fig. 12 is a side sectional view, Fig. 13 is a plan view showing the structure of the operation panel, Fig. 14 is a perspective view showing the structure of the drive section, and Fig. 15 is the drive of the optical system. FIG. 16 is a perspective view schematically showing the mechanism; FIG. 16 is a perspective view schematically showing the pointer drive mechanism;
Fig. 17 is a block diagram showing the overall control circuit, Fig. 18 is a block diagram of the main processor group, Fig. 19 is a block diagram of the first sub-processor group, and the 20th factor is a block diagram of the second sub-processor group. , FIG. 21 is a schematic configuration diagram showing the control circuit of the pulse motor, FIG. 22 is a diagram shown to explain the speed control method of the pulse motor, and FIG. 23 is a diagram showing the main parts of another arrangement example of the erasing array. FIG. DESCRIPTION OF SYMBOLS 1...Main body, 2...Document stand, 10...Photosensitive drum, 30...Operation panel, 308-30d...Operation key, 30e...Position specification key, 30f, 30o...
・Erase range specification key, 71...main processor group,
131... spot light source, 131a... light emitting element,
135...Motor, 140...Memory, 150...Erase array, 160...Array drive unit,
P... Paper, Ph... Exposure section. (a) M2 Figure 3 '1 Engineering 154 Figure (a) (b) Figure 4n (a) (b) Figure 5 Figure 6 Figure 23v!J Figure 7 (a) (b) Figure 9 15 '. Figure 10 Figure 20 Figure 21

Claims (2)

[Claims] (1) A scanning device that optically scans a document placed on a document table; an optical system that forms an optical image obtained by the scanning device onto a charged image carrier; and the image carrier. In an image forming apparatus comprising a developing means containing a developer for developing an image formed on a body, and a transfer means for transferring the developed image onto a transfer material, a range for specifying a predetermined range on the original document. a specifying means, and 1 for erasing from the image carrier an image in the range specified by the range specifying means;
An image forming apparatus comprising: an erasing means having a luminance of 500 millicandela or more. (2) The image forming apparatus according to claim 1, wherein the erasing means is comprised of a light emitting diode.