JPH0441330B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exposure scanning control device for an electrophotographic printing machine.

Conventionally, the exposure scanning system is moved forward parallel to the surface of the stationary document from the starting position to the ending position, and the photosensitive paper fed from the paper feeding section is moved at twice the speed of the exposure scanning system and at the same speed as the exposure scanning system. An electrophotographic engraving machine is used that sequentially exposes and projects an image of a document onto photosensitive paper by moving it forward in a direction.

Generally, this type of electrophotographic engraving machine includes an optical system drive motor and its drive control circuit for moving the exposure scanning system forward from a starting position to a terminal position when the photosensitive paper reaches a predetermined paper feeding position, and an optical system drive motor and its drive control circuit. The conventional lighting control circuit is equipped with a lighting control circuit for lighting an exposure lamp of an exposure scanning system for a certain period of time when the paper reaches the predetermined paper feeding position.
When the photosensitive paper reaches a predetermined paper feeding position, it operates regardless of whether the exposure scanning system itself is activated or not, so if the exposure scanning system does not operate due to a failure of the optical system drive motor. However, there was a problem in that the exposure lamp would turn on, causing damage to peripheral equipment due to overheating of the exposure lamp.

In view of the problems of the prior art described above, the present invention does not turn on the exposure lamp even when the photosensitive paper reaches a predetermined paper feeding position if the exposure scanning system does not operate due to a failure of the optical system drive motor. In this way, it is an object of the present invention to provide an exposure scanning control device that can prevent damage to peripheral equipment due to overheating of an exposure lamp.

According to the present invention, the above object is to move the exposure scanning system forward parallel to the stationary document from the starting end position to the final end position, and to move the photosensitive paper fed from the paper feeding unit at twice the speed of the exposure scanning system. In an electrophotographic engraving machine that exposes and projects the original image onto photosensitive paper by moving it forward in the same direction as the exposure scanning system,
a start sensor that detects that the photosensitive paper has reached a predetermined paper feeding position; a start end switch that detects that the exposure scanning system is at a starting end position; and a terminal end that detects that the exposure scanning system is at a terminal end position. a switch, an encoder that emits a continuous pulse signal in conjunction with the feeding operation of the photosensitive paper, a counter that counts the pulse signal from the encoder, and a a forward control circuit that moves the exposure scanning system forward; and a lighting control that lights up the exposure scanning system on the condition that the counter has counted a second predetermined number of pulses and the start end switch has not detected the exposure scanning system. a circuit, and the termination switch detects an exposure scanning system, or
On the condition that the counter has counted a third predetermined number of pulses, a signal is issued for clearing the counter and deactivating the advance control circuit and the lighting control circuit, and the start sensor detects photosensitive paper. This is achieved by an exposure scan control device for an electrophotographic engraving machine, which is characterized in that it is provided with an exposure scan end control circuit that requires the above conditions.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 1, the electrophotographic engraving machine has an electrophotographic engraving machine main body 1 consisting of a lower casing and an upper casing.
A translucent original platen 2 is fixed to the upper surface of the main body 1, a paper feed section 3 and a charging section 4 are provided at one end of the main body 1, and the main body 1 A developing section 5 and a fixing section 6 are provided on the other end side.

Below the document table 2, a scanning box 8 is mounted on a guide rail 7 disposed in the main body 1 parallel to the document table 2.
is provided so as to be able to reciprocate between a starting end position near the charging section 4 and a terminal end position near the developing section 5. As shown in FIG. 2, an optical exposure system 9 having an exposure lamp L ₁ , a focusing light transmitter 10 and an odd-numbered anti-tilt mirror 11 is supported on the scanning box 8 .
The exposure scanning system 9, together with the scanning box 8, is moved forward and backward by an optical system drive motor _M1 , as shown in FIG.

In FIG. 1, a paper feed roller device 13 for feeding photosensitive paper 12 one by one is provided in the paper feed section 3, and a charging section entrance roller device 14 is provided on the entrance side of the charging section 4. A developing section entrance roller device 15 is provided on the entrance side of the developing section 5, and a squeeze roller device 1 is provided on the exit side of the developing section 5.
6 is provided, and a paper discharge roller device 17 is provided on the exit side of the fixing section 6. Roller device 1
4 to 17 are rotationally driven by a main motor M ₂ , and the paper feed roller device 13 is rotationally driven by a paper feed motor M ₃ provided in the paper feed section 3 .

A photosensitive paper transport device 18 is provided between the charging section 4 and the developing section 5 for moving the photosensitive paper 12 forward at twice the speed of the exposure scanning system 9 in the same direction as the exposure scanning system 9. As shown in detail in FIGS. 2 and 4, the photosensitive paper conveying device 18 has two sets that move in the same direction and at the same speed as the exposure scanning system 9 and sandwich the photosensitive paper 12 before and after the exposure scanning system 9. roller devices 19, 20
As the scanning box 8 moves forward, both roller devices 1
9 and 20, and a rotation applying device 21 that applies rotation at a circumferential speed equal to the moving speed of the exposure scanning system 9.

The roller devices 19 and 20 include main rollers 22 and 23 located on the back side of the photosensitive paper 12, and a presser roller 2 that is pressed against the main rollers 22 and 23 by a spring (not shown) from the photosensitive side of the photosensitive paper 12.
It consists of 4 and 25. These main rollers 2
2 and 23 and press rollers 24 and 25 are each rotatably supported by the scanning box 8, and furthermore, the press rollers 24 and 25 are movable up and down.

A guide plate 26 for supporting the back surface of the photosensitive paper 12 is provided between both roller devices 19 and 20, and this guide plate 26 is fixed to the scanning box 8. The exposure scanning system 9 is arranged to form an inverted real image of the document surface directly on the photosensitive surface of the photosensitive paper 12 on the guide plate 26.

With reference to FIG.
7, and a pinion 28, 2 that meshes with the rack 27.
9, and the pinions 28 and 29 are connected to the main roller 2 via one-way clutches 30 and 31, respectively.
It is attached to 2 and 23. pinion 28,
The pitch circle diameter of 29 is equal to the diameter of the main rollers 22, 23, and the one-way clutches 30, 31
is the pinion 28, 29 accompanying the forward movement of the scanning box 8.
The main rollers 22 and 23 are formed to transmit only the rotation of the main rollers 22 and 23. Therefore, when the scanning box 8 moves backward from the developing section 5 side to the charging section 4 side, the rotation of the pinions 28 and 29 is not transmitted to the main rollers 22 and 23. The photosensitive paper conveyance speeds of the roller devices 13 to 17 are set to be approximately equal to the photosensitive paper conveyance speeds of the roller devices 19 and 20.

A fixed guide plate 32 is disposed below the scanning box 8 between the charging section 4 and the developing section entrance roller device 15, and extends substantially parallel to the document table 2.
The front end (left end in FIG. 1) of the fixed guide plate 32 slopes upward toward between the rollers of the roller device 15. Therefore, the front end of the photosensitive paper 12 sandwiched between the roller devices 19 and 20 is
It hangs downward until it reaches , but is guided by the fixed guide plate 32 and guided between the rollers of the roller device 15 . Further, the rear end of the photosensitive paper 12 held between the roller devices 19 and 20 hangs downward when separated from the charging section 4, but is received by the fixed guide plate 32.

The developing section 5 is provided with a pump motor _M4 for supplying developer to the photosensitive paper path, and the fixing section 6 is provided with a panel heater HT and its thermistor _R1 . A fixing unit fan motor F ₁ and an exhaust fan motor F ₂ are provided in the main body 1, and a device detects when the photosensitive paper 12 has reached a predetermined paper feeding position (in this case, the entrance of the charging unit 4). a start sensor PC ₁ that detects that the exposure scanning system 9 is at the starting position, a starting end switch S ₁ that detects that the exposure scanning system 9 is at the final position, a terminal end switch S 2 that detects that the exposure scanning system 9 is located at the final position, and a start sensor PC ₁ that detects that the exposure scanning system 9 is at the final position; An encoder 33 is provided which generates a continuous pulse signal in conjunction with paper movement. The encoder 33 consists of a disc 34 that rotates in conjunction with the roller device 14, and an encoder sensor PC ₂ that sandwiches the irregularities on the outer periphery of the disc 34. The encoder sensor PC ₂ rotates according to the rotation of the disc 34. It emits a continuous pulse signal.

Although not shown, a power switch _S3 , a power indicator lamp _L2 , a print switch _{S4, and a reload lamp L3 built} into the print switch _S4 are provided on the outer surface of the main body 1. ing.
Further, a door switch _S5 is provided within the main body 1 and is turned on when the upper casing of the main body 1 is closed with respect to the lower casing.

Referring to FIG. 5, the exposure scanning control device includes a counter CT that counts pulse signals from the encoder sensor PC ₂ of the encoder 33;
A forward control circuit 35 moves the exposure scanning system 9 forward on condition that the CT has counted a first predetermined number _of pulses; The lighting control circuit 36 turns on the exposure lamp _L1 of the exposure scanning system 9 on the condition that the exposure lamp L1 of the exposure scanning system 9 is not detected, and the termination switch _S2 detects the exposure scanning system 9, or the counter CT detects the third predetermined pulse. Counter CT on the condition that the number has been counted
emit a signal to clear the forward control circuit 35 and the lighting control circuit 36, and
It has an exposure scan end control circuit 37 that ends the transmission on condition that the start sensor PC ₁ detects the photosensitive paper 12.

The forward control circuit 35 includes a first decoder DEC ₁ that determines that the counter CT has counted a first predetermined number of pulses and issues a pulse signal;
It has a first latch circuit _FF1 that latches the pulse signal from the DEC ₁ , and a first drive circuit _DR1 that drives the drive motor _M1 of the exposure scanning system 9 forward by the output signal from the first latch circuit _FF2 . The reset terminal of the first latch circuit _FF1 is connected to the output terminal of the exposure scan end control circuit 37.

The lighting control circuit 36 includes a second decoder DEC ₂ that determines that the counter CT has counted a second predetermined number of pulses and issues a pulse signal;
A second latch circuit FF ₂ that latches the pulse signal from DEC ₂ , and an AND circuit G connected to the output terminal of the second latch circuit FF ₂ and connected to the start switch S ₁ via the first inverter INV ₁ . ₁ and
It has a second drive circuit DR ₂ that turns on the exposure lamp L ₁ of the exposure scanning system 9 in response to the output signal from the AND circuit G ₁ , and the reset terminal of the second latch circuit FF ₂ is connected to the exposure scan end control circuit 37 . is connected to the output terminal of

Here, the lighting control circuit 36 is further provided with a temperature sensor PC ₃ for the exposure lamp L ₁ , a converter C, and a temperature switch S ₆ .

The second predetermined number of pulses is set to a number (for example, 124) that is greater than or equal to the first predetermined number of pulses (for example, 112 in the case of 0.0124 seconds per pulse). In this case, a charger power source (not shown) for the charging section 4
HV can be set to be applied when the counter CT counts, for example, 8 pulses. Further, the third predetermined number of pulses is the exposure scanning system 9
When it reaches the position detected by the terminal switch S ₂ , the number is such that it has not yet reached the position (e.g. 1792)
Can be set to .

The exposure scan end control circuit 37 includes a third decoder DEC ₃ that determines that the counter CT has counted a third predetermined number of pulses and issues a pulse signal, and an output terminal of the third decoder DEC ₃ and a termination switch S ₂ 2 on the input side. OR circuit G ₂ connected to , and a third latch circuit that latches the detection signal of start sensor PC ₁
FF ₃ and a second inverter INV ₂ whose input side is connected to the output terminal of the third latch circuit FF ₃ , and the output terminal of the OR circuit G ₂ is connected to the third latch circuit FF _3.
The output terminal of the second inverter INV ₂ is connected to the reset terminal of the exposure scan end control circuit 37.
It constitutes the output terminal of.

Next, the operation of the apparatus of the above embodiment will be explained with reference to the timing chart shown in FIG.

When placing a document on the document table 2 and turning on the power switch _S3 , if the upper case is properly closed, the door switch _S5 will turn on and the power indicator lamp will turn on.
L ₂ , panel heater HT, main motor M ₂ , pump motor M ₄ , fan motors F ₁ and F ₂ and reload lamp L ₃ are turned on.

Next, when the print switch S ₄ is turned on, the paper feed motor M ₃ operates, and one sheet of photosensitive paper 1 in the paper feed section 3 is fed.
2 is sent to the charging section 4 side by the paper feeding roller device 13 and the developing section entrance roller device 14.

When the photosensitive paper 12 is detected by the start sensor PC ₁ on the entrance side of the charging section 4, the output signal of the exposure scan end control circuit 36 is input to the clear terminal of the counter CT, as shown in FIG. In order to
Counter CT starts counting pulses input from encoder _PC2 .

Here, the charging power of the charging section 4 is turned on with eight pulses, voltage is applied to the charging section 4, and the photosensitive paper 12 passing through the charging section 4 is negatively charged.

When the number of pulses is 112, the first drive circuit DR ₁ of the forward control circuit 34 of the optical system drive motor M ₁ is turned on, and the exposure scanning system 9 waiting at the starting position starts moving forward together with the scanning box 8. Exposure scanning system 9
With the start of forward movement, the start end switch _S1 is turned off, and the output signal from the inverter _INV1 is sent to the AND circuit _G1 . The second decoder DEC ₂ is the number of pulses
When 124 pieces are determined, a pulse signal is sent to the set terminal of the second latch circuit FF ₂ and the AND circuit G ₁
The output signal is sent to The second drive circuit DR ₂ is activated by the output signal from the AND circuit G ₂ ,
Turn on exposure lamp _L1 . According to the invention,
Optical system drive motor after actuation of start sensor PC ₁
If the exposure scanning system 9 does not move forward due to a failure of _M1 , etc., the start end switch _S2 will not turn off, so no output signal will be emitted from the AND circuit _G1 , and therefore the exposure Lamp _L1 is never turned on in such an abnormal situation.

The first predetermined number of pulses (here 112) is selected such that the scanning box 8 starts advancing before the front end of the photosensitive paper 12 reaches the roller arrangement 19. Therefore, the front end of the photosensitive paper 12 is located in the scanning box 8.
After starting to move forward, it catches up with the roller device 19 and is held by the roller device 19. In addition, photosensitive paper 1
If the scanning box 8 is stopped when the photosensitive paper 12 reaches the roller device 19, the front end of the photosensitive paper 12 reaches the roller device 1.
However, with the configuration as described above, the jamming phenomenon can be prevented and the transfer of the photosensitive paper 12 to the roller device 19 can be performed smoothly.

As the scanning box 8 moves forward, the roller device 19,
Since the main rollers 22 and 23 of 20 are rotated at a circumferential speed equal to the moving speed of the scanning box 8, the photosensitive paper 12 is rotated at the scanning box 8 at the roller devices 19 and 20.
The photosensitive paper 12 is transported at twice the moving speed of
Images of the document surface are sequentially projected onto the photosensitive surface of the document.

When the scanning box 8 reaches the end position, the end switch _S1
The detection signal of is sent to the OR circuit G ₁ and the OR circuit G ₁
The output signal from the second inverter INV 2 is sent to the reset terminal of the third latch circuit, and the output signal from the second inverter INV ₂ is sent to the clear terminal of the counter CT and the reset terminals of the first and second latch circuits FF ₁ and FF ₂ . each will be sent. Therefore, the counter CT is kept in a clear state, the first and second drive circuits DR ₁ and DR ₂ are kept in a de-energized state, the exposure lamp L ₁ is turned off, and the optical system drive motor M is kept in a de-energized state. ₁ forward movement is completed.

If the optical system drive motor _M1 breaks down during exposure scanning, the detection signal from the termination switch _S2 cannot be obtained, but in this case, the third decoder
Here, the DEC ₃ determines the number of pulses (1792) and sends an output signal to the OR circuit _G2 , so the exposure lamp _L1 will not remain lit.

When the optical system drive motor _M1 reaches the end position, it is then driven in reverse by a not-shown backward drive control circuit, and the scanning box 8 is moved backward toward the start position.

When the exposure scanning system 9 returns to the starting position, the starting end switch _S1 is turned on, and the main motors _M1 ,
The operations of the pump motor M ₄ , fan motors F ₁ and F ₂ , optical system drive motor M ₁ , reload lamp L ₃ and paper feed motor M ₃ are stopped. Thereafter, when the print switch _S4 is turned on, the main motor _M2 , paper feed motor _M3, etc. are operated again, and the next exposure scan control is performed.

Although one embodiment has been described above, the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention.

As explained above, according to the present invention, even when the photosensitive paper reaches a predetermined paper feeding position, the exposure lamp is not turned on if the exposure scanning system does not operate due to a failure of the optical system drive motor. Therefore, it is possible to provide an exposure scanning control device that can prevent damage to peripheral equipment due to overheating of the exposure lamp.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic sectional view of an electrophotographic engraving machine showing an embodiment of the present invention, FIG. 2 is a schematic sectional view of the inside of an exposure scanning system in the electrophotographic engraving machine shown in FIG. FIG. 1 is a perspective view showing the exposure scanning system conveyance device of the electrophotographic engraving machine shown in FIG. This figure is a main part electric circuit diagram of the exposure scanning control device of the electrophotographic engraving machine shown in FIG. 1, and FIG. 6 is a timing chart of the exposure scanning control device shown in FIG. 5. 1...Electrophotographic engraving machine body, 2...Document stand, 3
...Paper feeding section, 4...Charging section, 5...Developing section, 6...
...Fixing section, 8...Scanning box, 9...Exposure scanning system, 1
0... Focusing light transmission body, L ₁ ... Exposure lamp, 1
1...Odd number of times anti-tilt mirror, 12...Sensitive paper, M ₁
...Optical system drive motor, _M2 ...Main motor,
_M3 ...Paper feed motor, _PC1 ...Start sensor,
PC ₂ ... Encoder sensor, S ₁ ... Starting end switch, S ₂ ... Ending switch, CT... Counter, 3
4...Advance control circuit, 35...Lighting control circuit, 3
6...Exposure scan end control circuit.

Claims (1)

[Scope of Claims] 1. The exposure scanning system is moved forward in parallel to the stationary document from the starting position to the final position, and the photosensitive paper fed from the paper feeding section is exposed and scanned at twice the speed of the exposure scanning system. In an electrophotographic engraving machine that exposes and projects an image of a document onto photosensitive paper by moving forward in the same direction as the system, the electrophotographic engraving machine includes: a start sensor that detects when the photosensitive paper reaches a predetermined paper feeding position; and an exposure scanning system. a start end switch that detects that the exposure scanning system is at the end position; an end switch that detects that the exposure scanning system is at the end position; an encoder that emits a continuous pulse signal in conjunction with the feeding operation of the photosensitive paper; and the encoder. a counter that counts pulse signals from the; a forward control circuit that moves the exposure scanning system forward on the condition that the counter has counted a first predetermined number of pulses; and a forward control circuit that moves the exposure scanning system forward on the condition that the counter has counted a second predetermined number of pulses. and a lighting control circuit that lights up the exposure scanning system on the condition that the start end switch has not detected the exposure scanning system, and the termination switch has detected the exposure scanning system, or the counter has detected a third predetermined pulse. emitting a signal for clearing the counter and deactivating the advance control circuit and the lighting control circuit on the condition that the number has been counted; and on the condition that the start switch detects photosensitive paper, emitting the signal; 1. An exposure scan control device for an electrophotographic engraving machine, comprising: an exposure scan end control circuit for terminating the exposure scan. 2. The advance control circuit includes a first decoder that determines that the counter has counted a first predetermined number of pulses and issues a pulse signal, a first latch circuit that latches the pulse signal from the first decoder, and and a first drive circuit that drives a drive motor of the exposure scanning system forward by an output signal from the first latch circuit, and a reset terminal of the first latch circuit is connected to an output terminal of the exposure scan end control circuit. An exposure scanning control device according to claim 1, characterized in that: 3. The lighting control circuit includes a second decoder that determines that the counter has counted a second predetermined number of pulses and issues a pulse signal, and a second latch circuit that latches the pulse signal from the second decoder.
an AND circuit connected to the output terminal of the second latch circuit and connected to the start end switch via a first inverter; and a second drive that lights an exposure lamp of an exposure scanning system by an output signal from the AND circuit. The exposure device according to claim 1 or 2, characterized in that the reset terminal of the second latch circuit is connected to the output terminal of the exposure scan end control circuit. Scanning controller. 4. The exposure scanning control device according to claim 3, wherein the second predetermined number of pulses is set to be greater than or equal to the first predetermined number of pulses. 5. The exposure scan end control circuit includes a third decoder that determines that the counter has counted a third predetermined number of pulses and issues a pulse signal, and an input side connected to the output terminal of the third decoder and the termination switch. a third latch circuit that latches the detection signal of the start sensor, and a second latch circuit whose input side is connected to the output terminal of the third latch circuit.
an inverter, an output terminal of the OR circuit is connected to a reset terminal of the third latch circuit, and an output terminal of the second inverter constitutes an output terminal of the exposure scan end control circuit. An exposure scanning control device according to any one of claims 1 to 4, characterized in that: