JPS61255362A - Image forming device - Google Patents

Abstract

PURPOSE:To not only prevent a secret document from being copied but also inform the copying action of the secret document, by detecting a magnetic substance provided at one point or along one side of an original on which the secret document is described by means of a magnetic sensor which is provided on the 1st carriage and can make two-dimensional movement. CONSTITUTION:A guide shaft 130 is provided on the 1st carriage 411 along the section where the light of an exposure lamp 4 is intercepted and a magnetic sensor 131 is provided on the guide shaft 130 in a united but freely movable condition and can move in, for example, both x- and y-direction. The magnetic sensor 131 is composed of a case 131a fitted to the guide shaft 130 and a sensor unit 131b provided in the case 131a. Moreover, the magnetic sensor 131 is coupled with a timing belt (toothed belt) 134 provided along the guide shaft 130. When a pulse motor 135 is driven, the sensor 131 is moved in the direction intersecting the scanning direction of the 1st carriage 411 at right angles.

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 its problems]

-In particular, electronic copying machines have the ability to copy original images onto paper as they are, or to enlarge or reduce original images and copy them.

By the way, since conventional copying machines can copy confidential documents in the same way as normal documents, even if confidential documents are not taken out, confidentiality is not completely maintained.

Furthermore, it is convenient for practical purposes if it is known that a secret document is being copied.

[Purpose of the invention]

This invention was made based on the above circumstances,
The object is to provide an image forming apparatus that can prevent copying of confidential documents and can notify the copying of confidential documents.

[Summary of the invention]

This invention detects, for example, a magnetic body provided at one point or along one side of a document in which a secret document is written, using a magnetic sensor that is provided in one carriage and moves two-dimensionally, thereby stopping the copying operation and It is used to notify danger.

[Embodiments of the invention]

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

3 and 4 schematically show an image forming apparatus, such as a copying machine, according to the present invention. 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 a fixed scale 21 that serves 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. The original placed on the original table 2 is exposed to an exposure lamp 4 and a mirror 5.
．． By reciprocating the optical system 6.7 in the direction of arrow a along the lower surface of the document table 2, exposure scanning is performed during the reciprocation. 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 further passes through the mirror 9. The original image is reflected by the photoreceptor drum 10 and guided to the photoreceptor drum 10.
The image is formed on the surface of the

The photosensitive drum 10 rotates in the direction of arrow C in the figure, and the surface is first charged by the charging device 11, and then the image is exposed to slit light, thereby forming an electrostatic latent image on the surface. This electrostatic latent image is formed by toner being deposited by the developing device 12. ! It is now converted into four images.

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 15 or 16, passes through the paper guide path 17 or 18, and then passes through the registration roller. versus 19
and is guided to the transfer section by one pair of registration rollers. 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. Note that 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. 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 20, so that the toner image on the photoreceptor drum 10 is transferred by the action of the charger 20. . This transferred paper P is transferred to the peeling charger 2
1, the image is electrostatically peeled off from the photoreceptor drum 10 and conveyed by a conveyor belt 22, and is sent to a fixing roller 23 as a fixing device provided at the end of the conveyor belt 22, where the transferred image is transferred. It will be established. Then, paper P after fixing
is arranged to be placed on a tray 25 outside the main body 1 by a pair of paper ejection rollers 24. 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 the afterimage is erased by the snow removal lamp 28, so that the drum 10 returns to its initial state. It looks like this. Note that 29 is a cooling fan for preventing the temperature inside the main body 1 from rising.

FIG. 5 shows an operation panel 30 provided on the main body 1. 301 is a copy key for instructing the start of copying; 302
is a numeric keypad for setting the number of copies, etc., 303 is a display unit that displays the operating status of each part and paper jams, etc., 304 is a cassette selection key for selecting the upper and lower paper feed cassettes 13 and 14, and 30s 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 30a is a display for displaying the set magnification. A section 309 is a density setting section for setting copy density.

FIG. 6 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 for performing magnification change.

A mirror motor 32 is a motor for changing the distance (optical path length) between the mirror 5 and the mirror 6.7 for changing the magnification. 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. A drum motor 36 is a motor for driving the photosensitive drum 10. 37 is a fixing motor that connects the paper conveyance path 22 and the fixing roller pair 2.
3 and a motor for driving the paper discharge O-ra pair 24. Reference numeral 38 is a paper feed motor, which is connected to the feed rollers 15 and 16.
This is a motor for driving. A paper feeding motor 39 is a motor for driving the registration roller pair 19. 40 is a fan motor, which is connected to the cooling fan 29.
This is a motor for driving.

FIG. 7 shows a drive bridge 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, respectively, 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, two pulleys 47.47 are rotatably provided in the guide portion 46 of the second carriage 422 that supports the mirror 6.7 and are spaced apart in the axial direction of the rail 422. A wire 48 is strung around. 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, as the pulse motor 33 rotates, the belt 45 rotates, the first carriage 411 moves, and the second carriage 422 also moves accordingly. At this time, since the pulleys 47 and 47 act as movable pulleys, the first
The second carriage 422 is 1/1 of the carriage 411.
move in the same direction at a speed of 2.

Note that the moving directions of the first and second carriages 411 and 412 are controlled by switching the rotational direction of the pulse motor 33.

Further, on the document table 2, a copyable range corresponding to the specified paper is displayed. That is, the paper selection key 304
Assuming that the paper size specified by (1) is (1)
x/KJ.

ry-Py/Kl. This copyable range (X, V>
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.

As shown in FIG. 8, the above-mentioned pointers 51 and 52
．． 55 via a spring 56. The pulley 55 is a motor 58
This motor 58
The distance between the hands 51 and 52 can be changed by rotating the hands according to the paper size and magnification.

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. Then, when the copy key 301 is pressed, the first
The carriage 411 is first moved toward the second carriage 412, and then the lamp 4 is turned on and the carriage 411 is 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.

FIG. 9 shows the overall control circuit, in which the main processor group 71 and the first . It is mainly composed of a second sub-processor group 72 and 73. The main processor group 71 is
The operation panel 30 and various switches and sensors detect inputs from input devices 75 such as the cassette size detection switches 60r and 602, and drive the various chargers; A solenoid 27a1 controls the heater 23a1 of the pair of fixed rollers 23, the exposure lamp 4, and each of the motors 31 to 40.58 to perform the copying operation described above, and also drives the magnetic sensor 131 and the magnetic sensor 131, which will be described later. A pulse motor 135 is controlled to detect a secret document based on the output signal of the magnetic sensor 131, and accordingly, the operation of the copying machine itself is controlled or an alarm 139 consisting of, for example, a buzzer is sounded.

Among the above motors 31 to 40.58, motor 35.37
, 40 and the developing device 12, the toner motor 77 is controlled by the main processor group 71 via a motor driver 78, and
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 a lamp regulator 81, and the heater 23a is controlled by the main processor group 71 via a heater ILJ control section 82. From the main processor group 71, the first and second sub-processor groups 72
．． Commands to drive and stop each motor are sent to the first .
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.

FIG. 10 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. Also, 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 boat 93, and a size switch for detecting paper size and its respective inputs are connected to the input/output boat 94.
A copy condition setting switch and its respective inputs are connected to the input/output boat 95. Note that the input/output port 96 is an option.

FIG. 11 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 and amount of the pulse motor; when a set value is set from the microcomputer 101, it counts based on the value; and when it has counted out, it sends an end pulse to the interrupt line of the microcomputer 101. Output to. A reference clock pulse is input to the timer 102. 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 34 via the pulse motor driver 79. Note that the input/output board 103 is used, for example, when outputting status signals of each pulse motor to the main processor group 71.

FIG. 12 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, and 58 are connected to the input/output boat 114 via the pulse motor driver 80.

Figure 13 shows the control circuit of the pulse motor, and shows the input/output boat 121 (input/output boat 1 in Figures 11 and 12).
04.114) has a pulse motor driver 122
(corresponding to the pulse motor drivers 79 and 80 in FIG. 9) are connected, and the pulse motor 1 is connected to this pulse motor driver 122.
23 (the pulse motors 31 to 34, 36, 38, 39
．． 135) are connected to each other.

Figure 14 shows the speed control method of a pulse motor.
The figure (a) shows the speed curve of the pulse motor, and the figure (b) shows the phase switching interval. As is clear from this figure,
At first, the phase switching interval is long, gradually shortens, eventually becomes equal, then gradually becomes longer again, and then stops. That is, this indicates the slew-up and slew-down of the pulse motor, starting from the self-starting region, being used in the high-speed region, and finally falling down. In addition, t! , t2・
...tx indicates the time of the phase switching interval.

Next, a secret document detection means according to the gist of the present invention will be explained. In FIGS. 1A and 1B, a guide shaft 130 is provided in the first carriage 411 along a portion where the light of the exposure lamp 4 is blocked. This guide shaft 13
0, a magnetic sensor 131 is integrally and movably provided. For example, as shown in FIG.
It is possible to move in the direction. This magnetic sensor 1
Reference numeral 31 is composed of a case 131a attached to the guide shaft 130 and a sensor unit 131b provided inside the case 131a.

Further, the magnetic sensor 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 magnetic sensor 1
31 is moved in a direction perpendicular to the scanning direction of the first carriage 411. In addition, the pulse motor 91 of the guide shaft 130
A position sensor 138 consisting of a microswitch that detects the initial position of the magnetic sensor 131 is provided on the first carriage 411 located at the 35N end. This results in
For example, when the magnetic sensor 131 is moved, the lower end of the magnetic sensor 131 first comes into contact with the position sensor 138, so that the initial position is detected.

Further, as shown in FIG. 2, an identification portion ID made of a magnetic material is provided along one side of the document G in which a secret document is written. This identification section ID is made of, for example, an inconspicuous magnetic tape.

In the above configuration, the operation will be explained. As shown in FIG. 16, the first carriage 411 is normally stopped at a position Q farthest from the two fixed scales. Also,
The document G is set with the center of the fixed scale 21 as a reference. In this state, when the copy key 301 is operated, the first
The carriage 411 is returned to the fixed scale 21 at high speed. At this time, the magnetic sensor 131 is moved along a trajectory as shown in FIG. 16, that is, two-dimensionally.

As a result, the magnetic sensor 13 is
1 passes through the identification section ID, the output signal of the magnetic sensor 131 changes from a low level to a high level, for example. For example, as shown in FIGS. 17 and 18, even when a document is placed, the identification part ID is detected by the magnetic sensor 131 at point a or point B during the return operation.

When the main processor group 71 detects this signal, it is determined that the document set on the document table 2 is a confidential document. As a result, when the first carriage 411 reaches the fixed scale 21, the first carriage 411
operation will be stopped and no copying operations will be performed from now on. Also,
At this time, an alarm signal is output from the main processor group 71, and this signal is supplied to the alarm device 131. Therefore, this alarm 139 is sounded to notify the danger.

In this state, for example, after a predetermined period of time has elapsed, the first carriage 411 is again moved to the position farthest from the fixed scale 21 under the control of the main processor group 71, and the operation of the alarm 1139 is stopped. In addition,
If the set document is a normal document, it goes without saying that after the first carriage 411 is returned, a normal copying operation is performed from that position.

According to the above embodiment, the identification section 10 made of a magnetic material is provided on one side of the document, and the identification section ID is transferred to the first carriage 411.
A secret document is detected by detecting the two-dimensional movement of a magnetic sensor 130 provided in the copying machine, and the copying operation is stopped. Therefore, copying of confidential documents can be reliably prevented. What's more, if a secret document is detected, an alarm will sound. therefore,
You can learn about the act of copying secret documents.

Furthermore, since the identification section 10 is detected by two-dimensional movement of the magnetic sensor 131, the identification section 10 can be detected no matter how the document is set.

In this case, the magnetic sensor 131 is moved as shown in FIG. 19.

Furthermore, the first carriage 411 normally has a fixed scale 21
The machine is stopped at the farthest position from the machine, and when copying starts, first
A return operation is performed to detect the identification section ID of the document. Therefore, it has the advantage of fast detection speed.

In the above embodiment, the alarm device 139 is used as the notification means, but for example, this may be used as a transmitter, and the transmitter modulates the alarm signal and transmits it to a receiver located at another location.
The receiver may demodulate the alarm signal and cause an alarm to sound. With such a configuration, the act of copying a secret document can be known from a remote location. In addition, although an identification section IO made of a magnetic material was provided on one side of the document,
The present invention is not limited to this, and it may be provided in a part of the document, for example, as shown in FIG. In this case, the movement of the magnetic sensor during detection is performed minutely.

[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 prevent the copying of a secret document and can notify the user of the act of copying the secret document.

[Brief explanation of drawings]

1 to 19 show an embodiment of the present invention. FIG. 1(a) is a perspective view showing only the main parts of the image forming apparatus vIi, and FIG. 1(b) is a perspective view of the image forming apparatus iii. FIG. 2 is a side sectional view showing only the main parts; FIG. 2 is a diagram for explaining a manuscript in which a secret document is written; FIGS. 3 and 4 are diagrams showing the configuration of the image forming apparatus; FIG. 4 is a side sectional view, FIG. 5 is a plan view showing the configuration of the operation panel, FIG. 6 is a perspective view showing the configuration of the drive section, and FIG. 7 is the drive structure of the optical system. A schematic perspective view; FIG. 8 is a block diagram of the pointer drive mechanism; FIG. 11 is a block diagram of the first sub-processor group;
Figure 2 is a diagram showing the configuration of the second sub-processor group. Figure 13 is a schematic diagram showing the control circuit of the pulse motor. Figure 14 is a diagram for explaining the speed control method of the pulse motor. Figure 15 is the diagram of the magnetic sensor. FIGS. 16 to 191i21 are diagrams for explaining the movement state, respectively, are plan views for explaining the detection operation of a document in which a secret document is written, and FIG. 20 is a diagram showing the setting of the identification unit in another embodiment. FIG. 3 is a plan view for explaining the position. DESCRIPTION OF SYMBOLS 1...Main body, 2...Document stand, 30...Operation panel, 10...Photosensitive drum, 71...Main processor group, 131...Magnetic sensor, 135...Pulse motor, 138...Position sensor, 139...Alarm device,
ID...Identification section, P...Paper. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 (b) Figure 2 G Figure 3r:g Figure 6 Figure 8 Figure 12 Kyoutsu Figure 15 Figure 16 rl Figure 17! Figure 18 Figure 19

Claims (4)

[Claims] (1) In an image forming apparatus that optically scans a document placed on the document table by a scanning means that moves along the document table, and forms an image corresponding to a reflected light image from the document, horizontally along the document table provided in the means;
a detection means that moves two-dimensionally in the vertical direction and detects the identification portion of the secret document set on the document table; and a control means that stops the image forming operation when the detection means detects the secret document; An image forming apparatus comprising: a notification means that is driven by the control means when a secret document is detected by the detection means. (2) The image forming apparatus according to claim 1, wherein the detection means comprises a magnetic sensor. (3) The image forming apparatus according to claim 1, wherein the identification section is made of a magnetic material and is provided at one point or along one side of the document. (4) The scanning means is placed on standby at a position farthest from the reference position for setting the original, and the secret original is detected by the detection means when the operating means returns. The image forming apparatus according to item 1.