JPS60238810A - Scanner - Google Patents

Abstract

PURPOSE:To extend a life of a driving means and a rotation supporting member, and also to save an energy by rotating the driving means of a scanning mechanism at a low speed at the time of non-scanning by a beam. CONSTITUTION:A write controlling circuit 102, a timer 103, ROMs 104 (program), 105 (data table), RAMs 106 (working), 107 (nonvolatile), etc. are connected to a microprocessor 101, and also an operation display part 111, various detectors 113 (microswitch, proximity switch, etc.), and a motor, a high voltage power source, a lamp, a solenoid, etc., and a laser scan motor 312, and a semiconductor laser 344 are connected through an input/output port 110, an input port 112, and an output port 114 and a driving circuit 115, and an input/output port 117 and a motor driving circuit 118, and a printing data write controlling circuit 119 and a laser modulation circuit 120, respectively. When a scan is not executed by a laser beam from the semiconductor laser 344, a rotation of the laser scan motor 312 is set to a low speed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention 1] The present invention relates to a scanning device that scans a recording medium with a beam to record information from an external device onto the recording medium.

[Technical Background of the Invention and Problems Therewith] In this type of scanning device, a beam is irradiated onto a rotationally driven polygonal rotating body, and the recording photoreceptor is scanned by the reflected beam.

However, since the polygonal rotating body rotates at high speed,
If this scanning device is constantly rotated while the recording device is turned on, the load on the motor that drives this multifaceted rotating body will increase, and the life of this motor and the bearings of the multifaceted rotating body will be shortened. Maintenance becomes complicated.

OBJECT OF THE INVENTION] The present invention has been made in view of the above circumstances, and aims to
／、Jigāru Main Chukyōsaba ((Maichi Kyoucho Structure) In addition to reducing the load on the propulsion means to save energy, we also aim to extend the lifespan of the parts that support high-speed rotation, making maintenance and management easier. The object of the present invention is to provide a scanning device that is easy to use.

[Summary of the Invention] A summary of the present invention for achieving the above object is that during effective scanning with a beam, the driving means that goes into the scanning mechanism is rotated at a steady high speed, and during standby, the driving means is rotated at a low speed. It is something to do.

(The following is a margin) [Embodiment of the Invention] Hereinafter, a description will be given with reference to an illustrated embodiment to which the present invention is applied.

FIG. 1 is a block diagram of a system for recording information on a recording medium by a laser beam. Information from a host system 1 (electronic computer, word processor main body, etc.) that supplies information is given to a data control unit 2. The data control unit 2 converts the information given from the host system 1 into data corresponding to dots and stores it in the page memory.

This stored dot image data is transferred to the print control unit 10.
Send to 0.

The print control section 100 writes the input dot image data onto a recording medium by modulating a laser beam, develops and transfers it, and prints the dot image data on a recording sheet.

FIG. 2 shows a detailed mechanical diagram of a printer 300 with a video interface.
It has a built-in printing control section 100 shown in the figure.

In FIG. 2, 300 is the printer body, 301 is
photoreceptor for recording information by laser beam,
Reference numeral 302 denotes a charge removal lamp for removing the charge on the photoreceptor 301 to an initial state, and is composed of a plurality of red LEDs. Numeral 303 is a static elimination lamp for increasing transfer efficiency, and like the static elimination lamp 302, it is composed of a plurality of red LEDs.

304 is a charger for uniformly charging the photoreceptor 301 to a predetermined potential; 305 is the photoreceptor 301;
A transfer charger 306 is for transferring the developed toner onto the paper, and a peeling charger 306 is for separating the paper after transfer from the photoreceptor.

307 is a developing device for developing an electrostatic latent image written on the photoreceptor 301 by a laser beam;
08 is a component of the developing device 307, which is a magnetic roller for adhering the toner to the electrostatic latent image on the photoreceptor 301, and rotates in the direction of the arrow; 309 is the developer of the magnetic roller; The A-toner probe 310, which is in contact with the developer and measures the specific toner density of the developer, is a cleaning blade that removes toner remaining on the photoreceptor 301 after transfer.

311 is the video data input from the data control unit,
A laser scanner unit 313 scans and modulates a laser beam onto the photoreceptor 301 for recording.
01 a polygonal rotating body such as an octahedral polygon mirror, 312 a scan motor 314 which is a driving means for rotating the polygon mirror 313 at high speed;
is an f 2 ·θ lens for keeping the scanning speed of the laser beam on the photoreceptor 301 constant. 315 and 3
Reference numeral 16 denotes a reflecting mirror for guiding the laser beam from the scanner unit 311 to the photoreceptor 301.

317 is an upper cassette that can hold 500 sheets of paper.
318 is an upper paper feed roller for taking out sheets of paper one by one from the upper cassette 317; 319 is an upper paper out switch for detecting that there is no paper in the upper cassette 317; and 320 is provided in the upper cassette 317. , an upper cassette size detection switch consisting of 4 bits for detecting a size identification mark. Reference numeral 321 indicates a lower paper feed roller, 323 indicates a lower paper out switch, and 324 indicates a lower cassette size detection switch. In addition, the upper section can store 250 sheets of paper from the lower section, and can also be used with cassettes.

326 is a manual feed switch that detects the paper inserted from the manual feed guide 325; 327 is a manual paper feed roller that conveys the paper after the insertion is confirmed by the manual feed switch 326; 32
Reference numeral 8 denotes a manual stop switch that detects the paper conveyed by the manual paper feed roller 327.

Reference numeral 329 denotes a registration roller for synchronizing the image developed on the photoreceptor 301 and the paper.

330 is a conveyor belt for conveying the paper separated by the peeling charger 306 to a fixing device; 331 is a fixing device for fixing the transferred toner on the paper;
332 is a fixing roller, 333 is a heater lamp for heating the fixing roller, 334 is a thermistor for detecting the surface temperature of the fixing roller, 335 is a discharge roller, and 336 is a sheet discharged from the fixing device 331. This is a paper ejection switch for detecting paper.

337 is a cooling fan for cooling the inside of the printer 300, and 338 is the charger 304 and the transfer charger 305. A high-voltage transformer that generates high voltages to be applied to the peeling charger 306, the developing device, and the magnet roller 308, respectively.

339 is a power supply device that generates DC voltages used for each control, and 340 is a PC board unit that controls the printer 300.

342 is a photoconductor 301 provided near the photoconductor 301;
A thermistor with extremely low thermal resistance is used in the drum temperature sensor to detect humidity.

FIG. 3 is a perspective view schematically showing a portion for recording information on the photoreceptor 301 using a laser beam. In FIG. 3, a laser beam emitted from a semiconductor laser 344 is corrected into parallel light by a collimator lens 343, and the parallel light is applied to one surface of an octahedron of a polygon mirror 313. Since the polygon mirror 313 is rotated at high speed in the direction of the arrow by the scan motor 312, the laser beam incident on the polygon mirror passes through the f/θ lens 314 and reaches the beam scanning range 3.
48 ranges are scanned from left to right. A part of the laser beam within the beam scanning range 348 is reflected by the reflecting mirror 3.
45 to a beam detector 346. Therefore, each time one horizontal scan by one surface of the polygon mirror 313 is performed, the beam detector 346 detects the laser beam being scanned. Further, the laser beam that is not incident on the reflection mirror 345 within the beam scanning range 348 is irradiated onto the photoreceptor 301 . In FIG. 3, the location where the laser beam is scanned on the photoreceptor 301 is shown at 349. 30
4 represents a charging charger, and 347 represents a sheet of paper. Incidentally, as shown in Fig. 2, the actual printer has an f/θ lens 3.
The laser beam that has passed through the laser beam 14 is not directly irradiated onto the photoreceptor 301, but is guided to the photoreceptor 301 by being reflected by reflection mirrors 315 and 316; however, for convenience in FIG.
6 is not shown in the figure, and the photoreceptor 301 is directly irradiated with a laser beam that has passed through the f/θ lens 314.

Here, the configuration of the reflecting mirror 345 will be explained with reference to FIG. 42. As shown in the figure, this reflecting mirror 345 is attached to a support member 456 that is positioned outside the beam incidence area with a screw 455 via a leaf spring 454, and a fine adjustment screw 457 is attached to the bottom of the leaf spring 454.
is provided so that the angle of the reflecting mirror 345 can be changed.

As is clear from FIG. 2, the laser scanner unit shown in FIGS. 3 and 42 is shielded from the outside to prevent the scanning beam from leaking. The results of beam detection by the beam detector 346 are displayed at appropriate positions on the scanning panel shown in FIG.

FIG. 4 is an explanatory diagram of the bus sensor 394 in front of the registration roller. Manual stop switch 3 in Figure 2
28 only detects manually fed paper, whereas the purpose of the registration roller front bus sensor 394 is to detect paper during paper feeding from a cassette. In FIG. 4, the paper fed from the upper cassette 317 and the lower cassette 321 by either the upper paper feed roller 318 or the lower paper feed roller 322 is fed along the paper guide plate to the registration roller 329. be done. At this time, if paper feeding is performed correctly, the light emitted from the light emitting diode 393 is blocked by the paper and the light emitted from the light emitting diode 393 is blocked by the registration roller (front,
No light for 4km. You can check the paper that has been fed. Furthermore, if the paper is not fed correctly, the paper does not reach the position of the registration roller front path sensor, and the light from the light emitting diode 393 continues to enter the registration roller front path sensor. , it is possible to recognize that paper has not been fed.

FIG. 5 shows a reversing tray 381 which is an optional unit.
FIG. Normally, the printer 300 is equipped with a non-reversible tray 397 as shown in FIG.

When such a non-reversing type is used, the first printing paper is on the bottom side, so the information delivery device (host system 1) has to send data from the last page, so the host There is a drawback that the method of filing information in system 1 becomes complicated. Therefore, the book reversing tray 381 is indispensable in order to compensate for the above-mentioned drawbacks.

In FIG. 5, the paper that has passed through the paper ejection roller 335 of the printer 300 is transported by transport rollers 382 and 383.
The sheet is stored in the tray 384 in an inverted form from when it passes the sheet discharge roller 335.

Therefore, since the printing side of the paper is on the bottom side, the first page is on the bottom side, but if you take out the paper from the tray 384 and turn the printing side of the paper on the front side, the first page will be on the top side and the last page will be on the bottom side. The page is on the lower side, and the above-mentioned drawbacks of the non-reversible tray 397 can be solved. In the figure, 385 is a paper stopper that can be slid according to the length of the printing paper in the conveyance direction. 388 is a paper holding actuator to prevent the paper stored in the tray from floating; 395 is a paper ejection switch to confirm that the paper is properly stored in the tray 384; and 391 is the presence or absence of paper in the tray 384. 392 is a tray sensor on the light receiving side. When the paper 390 is in the tray 384, the tray sensor 392 is not irradiated with light, and when there is no paper 390, the tray sensor 392 is irradiated with light, so that the presence or absence of the paper 390 can be detected.

The other side of the paper presence/absence and paper full detection section is shown in FIG. This causes the actuator 38 to rotate around the pivot point 386.
8 is provided, and a lever 398 is provided in series above,
The tip of the lever 398 is biased in one direction by a solenoid 389 as a separating means and a coil 387 as a releasing means, and the lever 398 is moved depending on the state in which paper is stored in the paper storage section 390. is detected by a detection means, for example, a plurality of sensors 401 and 402. In the various states of the actuator 388, the position al is "E paper full", the position a2 is "paper present", a
Position 3 is in the "out of paper" state. The separating means 38
Reference numeral 9 separates the actuator 388 at least while the paper 390 is being discharged into the paper output tray 384, and activates the solenoid in synchronization with the current state signal when the paper should be detected, for example, during a printing operation or when the paper is stopped. 389 is turned off,
The separation of the actuator 388 is released, and a detection operation is performed. Therefore, the discharging leading end of the paper 390 does not collide with the actuator 388, and the discharging operation is not hindered.

Note that each sheet of paper sent into the paper ejection tray is detected by a paper ejection switch 395, and the contents are counted by a paper ejection memory counter (RAM 107 in FIG. 13), which will be described later, to detect the number of sheets. When the paper becomes "full", it is displayed on the tray full lamp 358 in FIG. 6, and the memory counter is cleared.

FIG. 6 is a detailed diagram of the operation panel of printer 300.

In FIG. 6, 350 is a top cover of the printer 300, 351 is a front cover, and 352 is a maintenance cover.
If a paper jam or toner replenishment occurs, open it in the direction of the arrow and process it. Further, the maintenance cover 352 is
Although the front cover 351 has a structure that can be opened from the top, it cannot be opened unless the front cover 351 is opened in the direction of the arrow, to prevent the operator from operating incorrectly.

353 is a 6-digit mechanical counter, which is incremented by 1 each time a sheet of paper is printed. 354 is a select switch for selecting online/offline, and 355 is a select lamp that corresponds to the select switch 354 and lights up when online.

356 is a 1-digit seven-segment LED that displays the error details when a serviceman is called, the mode number when in maintenance mode, etc., and 357 is the printer 30.
A power lamp that indicates that the power is turned on.
Reference numeral 358 indicates a tray full lamp that indicates that the reversible tray unit 381 is full of printing paper, and reference numeral 359 indicates a color LCD display that displays details of the operating status of the printer. The total counter 353 to LCD display 359 described above are constantly operated or displayed. Next, the maintenance cover 352
This section explains the parts that cannot be operated without opening the . The following parts are to be operated only by service personnel.

403 is a maintenance cover for selecting maintenance mode and replacement mode, and 406 is an indicator lamp indicating that the system is in maintenance mode.

407 is an indicator lamp indicating that it is in exchange mode;
404 is a selection switch that selects the operation mode number in each mode; 408 is a selection lamp that indicates that the selection operation by the selection switch 404 is possible; 405 is a test print mode selection and the above-mentioned maintenance, replacement, and test print. 360 is a main exposure adjustment volume which will be described later, and 361 is a shadow exposure adjustment volume. Further, both volumes 360 and 361 have a structure in which an adjustment screwdriver is inserted and turned, and cannot be turned by hand with the maintenance cover 352 open.

FIG. 7 is a detailed diagram of the LCD display 359, and the function of each display segment will be explained below.

371.372 is a segment indicating the standby, ready state, etc. of the printer 300. When waiting until the fixing unit is ready, both 371 and 372 are lit, in the ready state, only 371 is lit, and during printing operation, both 371 and 372 are turned off. .

373 blinks when a jam occurs in the paper feeding section, and segments 1 to 373 indicating the paper feeding status also blink at the same time.

That is, the manual feed designation 365 blinks in the manual feed mode, the upper cassette 364 blinks in the upper cassette mode, and the lower cassette 363 blinks in the lower cassette mode.

374 blinks if there is a jam in the conveyance system (registration roller 329 or later). At this time, the paper feed segment also blinks at the same time, as in the case of a paper feed jam. 375, the toner collected by the cleaning blade 310 in FIG. 2 is a toner pack (not shown)! Blinks when fi is full. 37
6 is a toner hopper of the developing device 307 (not shown)
Flashes when the toner runs out. 377 and 378 blink when a serviceman error, which will be described later, occurs. 3
79 blinks when an operator call, which will be described later, occurs. 380 blinks if there is no paper in the selected cassette. 362 displays the size of the selected paper. For example, if the upper cassette side is selected and the
If it is a vertical paper cassette, A4-R lights up, and if 80 is selected in manual feed mode, 86 lights up. 363
364 lights up when the lower cassette is selected, 364 lights up when the upper cassette is selected, and 365 lights up when manual feed is selected. 366 represents the shape of the printer 300 and is always on; 367 represents the photoreceptor 301 and is always on; 368 is the printer 30
369 is lit at all times except when the conveyance section is jammed, and 368 is alternately lit when the conveyance section is jammed (when 374 is blinking). Reference numeral 370 indicates five segments that display the conveyance state of the paper, and one segment moves from the right side to the left side while lighting up.

FIG. 8 is a schematic block diagram of the data control section 2 in FIG. 1. The data control unit 2 converts the character code information and image information sent from the host system 1 into a dot-compatible page memory 20 that corresponds to the print area on the paper of the printer 300 and then stores the data. Further, the stored data on the page memory 20 is sent to the printer 300 to perform a printing operation.

The data control unit 2 is configured to accept two types of information. In other words, one is character code information (JISB
In this case, the character generator 15 generates a character pattern corresponding to the character code, and stores the dot information of the character pattern on the page memory 20. The other is image information, and in this case, it is already input in the form of dot information, so it is stored in the page memory 20 as is. Hereinafter, an overview of the data control section 2 will be explained with reference to FIG.

Information from the host system 1 is sent to the interface 50 via the signal line S01, and the information is further stored in the data latch 3.

Signal line 8 between interface 50 and host system 1
02 is sent from the host system 1. A data strobe signal and other control signal line 803 are a busy signal and status signal line from the data control device.

The format of the information sent from the host system 1 is shown in FIGS. 9 and 10. The format example in Figure 9 is for character code information, where a character identification code indicating that it is character code information and a paper size code indicating the size of the paper to be printed are placed at the beginning of one page. There is.

Thereafter, character code data is entered in the order of the first line, second line, . The character data for one line consists of a code indicating the character size, a character code, and an LF code indicating the delimitation of one line of data.

FIG. 10 shows a format for image information, in which an image identification code indicating image information and a paper size identification code indicating the size of paper to be printed are entered at the beginning of one page of data. After that, 1 line.

2 lines...The image data is arranged in the order of m lines. Furthermore, since the data for one line is specified by the paper size identification data, it is automatically determined by counting the specified data on the data control unit 2 side. There is.

The input information from the distributor 4 is processed as follows. The information that has entered the distributor 4 is always input from the distributor 4 to the decoder 5 via the output line S04. First, regarding the case of character code information, when the character identification code shown in FIG. The main control unit 6 determines that the input information is character code information, and sends the next paper size data to the distributor 4 via the signal line 806 to the basic code buffer 7III11 circuit 7.
command to input. Therefore, the paper size data is sent from the distributor 4 to the page code buffer 7 via the data [1807].
Input to the control circuit. The next 1st line, 2nd line...
...The data up to the nth row is sent from the distributor 4 to the data line 8.
It is input to the page code buffer 7 via 0B. At this time, the character code data is stored in a memory area on the base code puffer 9 designated by the address counter 8. When the input of character code information for one page into the page code buffer 1 is completed and the END code shown in FIG. 9 is detected by the decoder 5, the main control unit 6. END code detection is transmitted to the page code buffer 1 control circuit 7. When the page buffer control circuit 7 confirms through the signal line 809 that input of character codes for one page into the page code buffer is completed, the data is stored in the page memory 20 in units of dots.

FIG. 11 shows the correspondence between memory spaces on the page memory 20 and sheets. In FIG. 11, broken lines indicate the outside of each sheet. That is, 25 is the leading edge of the paper (common to all sizes),
24 is the left edge of the paper (common to all sizes), 28 is the right edge of A5 size paper, 27 is the right edge of A4 size paper, 26 is A3 size paper
The right edge of size paper, 31 is the rear edge of Δδ size paper, 30
29 indicates the rear end of A4 size paper, and 29 indicates the rear end of A3 size paper. 32 is a read address counter 19
and the address ADR of the write address counter 18 (
0,0) points. Here, ADH (0, O) indicates that both the vertical address (ADRV) and the horizontal address (ADR) -1> are 0'. In other words, the write address counter 18 and the read address counter 19 are made up of a vertical address (ADRV>) and a horizontal address (ADR, H), as shown in FIG.
1 arrow b), and ADRH is the horizontal address (
It is designed to represent arrow C) in Fig. 11.

43 is the last horizontal address of A3 size paper (A3) I
E), 44 is the horizontal address of A4 size paper (A4HE
), 45 is the horizontal address of A5 size paper (A58E)
It is. Similarly, 46 is the last vertical address of A3 size paper (A3VE), 47 is the vertical address of A4 size (A4VE), and 48 is the vertical address C of A5 size paper.
A5VE). 33 is A3 size vertical address ADRV=O, horizontal address ADRH=A38E point ADR (0, A3HE), 34 is TADR in the same way
(0, A4HE), 35G, tADR (0, A5HE)
are shown respectively. Also, 36 is A3 size (D vertical 7 do L
/SADRV= (A3VE).

Point ADR (A3VE) of horizontal address ADRH=O
, 0), 37 are similarly ADR(A4VE, 0), 3
8 indicates ADR(A5VE, O)u, respectively. 39 is A3
Size vertical address ADRV = A3VE, horizontal 7 address ADRH = A3HE point ADR (A3VE,
A31-IE), similarly 40 is ADR (A4VE)
, A4HE).

41 indicates ADR (A5VE, A5HE), respectively. Storing a character pattern as a dot image in the page memory 20 having the above-mentioned memory space is performed as follows. The character size data of the first line is read from the page code buffer 19 to the page code buffer control circuit 7 via the signal line S10. In this embodiment, there are two basic types of font sizes: 40x40 and 32x32 dots, and the page code buffer 7 control circuit 7
Then, the character size is determined based on the read character size code, and the determination signal is sent to the page memory control circuit 17 via the signal line S11 and to the character generator 15 via the signal line 313, respectively. Page memory control circuit 1
At 7, the line feed pitch and character pitch are controlled by the character size discrimination signal, and at the character generator 15, the character size area is switched.

The character code after the character size data is stored in the line address counter 11 in the line buffer 1o, which has a memory capacity for one line.
will be transferred to the specified area.

When the transfer of one line of character code data to the line buffer 1o is completed, the line address counter 11 returns to the initial address (
Return to 0). First, the first vertical line of the character font (line 57 in FIG. 11) is written into the page memory 2o once.

Here, the line/scan counter 13 has an initial value (0,
0), and the write address counter 18
The value of is ADR(0,0). row buffer 10
The character code data is sequentially read out in a constant cycle starting from the first digit, and is latched in the output latch 12 in order to synchronize with the line counter 13. The first character code (l T 1 character in this example) is output latch 1.
2, the character [-] and the output of the line/scan counter 13 are synthesized by the synthesis circuit 14 and input to the character generator 15 as a character pattern selection code. here,
To explain the configuration of the line/scan counter 13, the upper 6 bits are a counter that counts scanning lines, that is, a counter in the vertical direction of the character pattern.
The line feed pitch control line counter returns to "0".

The lower 3 bits serve as a counter in the horizontal direction of the character pattern, and in the case of a 40x40 dot font, it counts from 0 to 4 plus the character pitch control and returns to 0' (because the output of the character generator 15 is 8 bits parallel) ).

Below, the font size is 40X40. The operation in the case where the horizontal distance between characters is 8 bits and the vertical distance between two characters is 8 bits will be described. As mentioned above, the first character code ('
T') is set in the output latch 12, the character code and the output of the line/scan counter 13 are combined in the synthesis circuit 14, and the character generator 15 outputs the code as a character pattern selection code for the character generator 15.
is input. At this time, since the value of the line/scan counter is (0, O), the output of the character generator 15 contains the data (8 bits) of the ``0'' line in the vertical direction and the ``0'' line in the horizontal direction. ) is output.The output data of the character generator 15 is output from the output latch 1 in order to synchronize writing to the page memory 20.
-H is latched at 6 and written to the address on the page memory 20 designated by the write address counter 18 by the page memory control circuit 17. In this case, since the value of the write address counter 18 is ADR (0, 0), the data is written to the vertical address '0' and the horizontal address 'O'. Then, when writing of the 1-byte character pattern is completed, the value of the line/scan counter is (0, 1
>, and the value of the write address counter 18 also changes to A.
Changes to DR(0,1). Therefore, the character generator 15 outputs the data of the ``0'' line in the vertical direction and the ``1'' line in the horizontal direction.
is written to the ADR (0, 1) address. In this way,
When writing of the last data of vertical line '0' (data at '4'4') of one character pattern is completed, the value of the line/scan counter is (0,5), and the value of the write address counter 18 is becomes ADR(0,5). The horizontal spacing between characters is 8 dots (1 byte), so
All outputs of the character generator 15 are forced to O' by a command from the page code buffer 1 control circuit 7.
Then, 0' is written to the ADR (0, 5) address of the page memory 20, and after the write operation is completed, the row address counter is incremented by "1" and the next character code is output from the row buffer 10 to the latch 12. Also, the line/scan counter is set to (0, 0>, write address counter 1
8 becomes ADR (0, 6). Therefore, next is the page memory 20 of the data of the 0'th line in the vertical direction of the character pattern O'.
A write operation is performed. At this time, the write address counter 18 is ADR (0, 6), (0, 7), (0, 8).
, (0°9), and (0, A), and write character pattern data of 0 to the address specified by the writing address counter 18.

Then, the value of the write address counter 18 is (0°B),
When the value of the line/scan counter 13 becomes (0°5), 0' is written to the page memory 20 in the same way as described above, and after the write operation is completed, the row address counter becomes plus 1.
', and the next character code is set in the output latch 12 from the line buffer 10.

Further, the line/scan counter 13 becomes (0°0), and the write address counter 18 becomes ADR (0°C).

In this way, the character pattern data of the +01st line in the vertical direction is sequentially written to the page memory 20, and when the ``LF'' code is output to the output of the line buffer 10, the ``LF'' code is detected. The signal is transmitted to the page code buffer 1 control circuit 7 through the output line 814, and the character pattern writing operation from the character generator 15 is stopped. After that, the write address counter 18 is sequentially incremented by 1' and 0' is forcibly written into the page memory 20. Then, if the value of the write address counter 18 is currently designated as A3 size, AD
When the value of R(0,A3HE> is reached, that is, the 33rd point in FIG. The scan counter 13 is set to (1, O), respectively. Then, T', which is the first character code from the line buffer 10, is set to the output latch 12 again. The character pattern data for the line is written to the page memory 20. Similarly, the character pattern data is written in the vertical direction '2'.

When the write operation up to the 3'...'39' line is completed, the write address counter 18 registers ADR (28,
O), and the row address counter 11 is (O).

The line/scan counters 13 are each set to (28, O). This completes the writing operation of character pattern data for one line, but since the line feed pitch is every 48 lines, 0' is forcibly written into the page memory 20 for the remaining eight lines. When the writing of 0' for 8 lines is completed, the address value of the writing address counter 18 is changed to the point 61 in FIG.
30,0), the row address counter 11 is (0).

The line/scan counters are each set to initial values (0, 0). This completes all write operations including the line feed pitch for one line. Then, character code data for the next second line is transferred from the page code buffer 9 to the line buffer 110. When the transfer of character code data is completed, the row address counter 11 returns to the initial address (0). Thereafter, character pattern data on the second line is written in the same manner as writing the character pattern data on the first line. Therefore, when all the self-writing operations for the character pattern data on the second line are completed, the address value of the write address counter is ADR (60, 0), and the address value of the row address counter 11 is (O
), the line/scan counters are set to (0,0), respectively. In this way, the character codes of each line are sequentially patterned and the pattern data is written onto the page memory 20. Then, when an ``END'' code indicating the last line is detected from the line buffer, the data writing operation of the character pattern is stopped. Then, the page code buffer control circuit 7 forcibly sets the output of the character generator 15 to 0' via the signal line S13, and notifies the page memory control circuit 17 that writing of character pattern data has ended.

After receiving the write end signal, the page memory control circuit 17 selects the final memory address (39 point ADR (A3VE) in FIG. , A3
Then, 0' is written at point 39 in FIG. 11, and the entire writing operation of character pattern data for one page of the specified paper size to the page memory 20 is completed. Then, the write address counter 18 is initialized to ADR<0.0, the row address counter 11 is initialized to (0), and the line/scan counter 13 is initialized to (0,0>).

Next, a case where the data sent from the host system 1 is image information will be described. When the image identification code shown in FIG. 10 is input to the decoder 5, the output of the decoder 5 is input to the main control section 6 via the signal line S05. Main control section 6
Then, it is determined that the input information is image information, and the signal line 806 instructs the distributor 4 to input the next paper size data to the page memory control circuit 17.

Therefore, the paper size data is sent from the distributor 4 to the data line 807.
The data is input to the page memory control circuit 17 via the page memory control circuit 17. Next image data 1, 2. ...The image data up to the next one is sent from the distributor 4 to the page memory 20 via the data line 815.
is input. The method of inputting image data to the page memory 20 is performed as follows. When the page memory control circuit receives the paper size identification code, it stores the next image data at 32 points (address ADR (0, 0)) in FIG.
Set the write address counter 18 to 80R(
0, O). Then, the data length for one line in the horizontal direction is determined from the paper size identification code by referring to a table in the page memory control circuit 17. Therefore, if the paper size of the image information to be input into the page memory 20 from now on is A4, the data length of one line is the value up to 44 points (A4) - IE) in Fig. 11.
That is, 'A48E'. The length of the image information per line sent from the host system 1 is naturally 84HE', so the image data 1 in Figure 10
1 image data 2. ...The data length of the image data is °A
4VE', and the number m of image data is the value of 47 points in FIG. ADH (0, O) ~ 34 point ADR (0°A4HE), image data 2 is a 51 point line, image data 3 is a 52 point line...
...Image data m is a 37-point line, so the final address is 40-point ADR (A4VE, A4HE)
becomes. Image information is written into the page memory 20 while controlling the write address counter 18 in this manner.

The character pattern data 13 written in the page memory 20 in this manner is sequentially outputted to the latch 21 . Gate circuit 23. Data to be printed is sent to the print control unit via the interface 22 and the inter-7/8 bus 817. In FIG. 8, 817 is a status data line from the print control unit, 818 is a command data line for specifying the operation mode, etc. to the print control unit, S19 and S20 are strobe signal lines when sending command data and print data,
S21 is a busy signal line from the print control unit, S22
is the horizontal synchronization signal line from the print control section, S23 is the page end signal line that also indicates the end of print data, and S2
Reference numeral 4 denotes a ready signal line of the print control unit, S25 a print request signal line for notifying a printable state, and 826 a select signal line (2 lines) for specifying the data content of the data line in the interface bus 817.

Reference numeral 827 is a print start signal line that instructs the print control section to start a print operation.

To explain in more detail when data is sent to the print control unit, printing from the data control unit 2 is started via the start signal line 827.
In contrast, the print control section sends a horizontal synchronization signal 822.

This horizontal synchronizing signal 822 first sequentially sends out each data of the 32-point line in FIG. S2
2, the address is sequentially changed line by line according to the page end signal 823 from the print control unit.
This operation is repeated until the page end signal 823 is received, and the data in the designated area of the page memory 20 is sent to the print control unit.When the page end signal 823 is received, the data sending is forcibly stopped. In the print control section, the page end signal 823 is output at the same timing as the horizontal synchronization signal 822. Also, in correspondence with the memory addresses in Figure 11, the last line A3 of the memory area of the paper size has 46 points, and A4 has 47 points.
It is output from the print control unit at the same timing as the point or before it.

Further, in the page memory control circuit 17, the page memory 20
When the sending of print data starts, the values of the read address counter 19 and the write address counter 18 are always compared, and if the value of the read address counter 19 is larger, the sending of that data is finished. control is performed to permit write operations to the memory area that has been accessed. Therefore, the loss of writing time to the page memory 20 is greatly reduced.

FIG. 13 shows a block diagram of the print control section 100 in FIG. 1. In FIG. 13, 101 is the print control section 100.
A microprocessor 1102 for controlling each unit in the microprocessor 1102 is an interrupt control circuit for controlling interrupts to the microprocessor 101, and a command signal line 830. Page end signal line S29 from print data write control circuit 19. Interrupt request signals from each of the timeout signal lines 828 from the general-purpose timer 103 are sent to the microprocessor 10.
Tell 1. A general-purpose timer 103 generates basic timing signals for controlling paper conveyance, drum rotation processes, and the like. In this embodiment, this general-purpose timer 103 has five
It is set to m5ec. A ROM (read only memory) 104 contains all control programs for operating the print control section 100. 105
are the same <ROM and contain a data table different from that of the ROM 104. The contents of the data table are the 45th
Figure 45 (A) shows the address (4) in Figure 45 (A).
000, 4001> contains top margin control data and addresses (4002, 4003) for paper size A3
contains bottom margin control data and address (4004
, 4005> contain data for left margin control, and addresses (4006, 4007) contain data for right margin control, respectively. Similarly, the address (40
08-400F>, the top for paper size B4,
Contains bottom, left, and right margin control data. Margin control data corresponding to various paper sizes is included up to address ('4087). These margin control data are used as set data for a margin control counter in a print data write control circuit 119, which will be described later.

Addresses (4100 to 41FF) contain a table of command codes for specifying operations from the data control unit 2, and are used for checking command codes from the data control unit 2. The content of the command is a top/bottom margin change table.

These include a top margin adjustment table, a cassette upper/lower adjustment table, a cassette/manual feed adjustment table, etc. Addresses (4200 to 42FF) contain data on the charging characteristics of the photosensitive drum 301, including five types of data A to F. This data is then used for temperature correction control of the charging charger 304, which will be described later. Addresses (4300 to 43FF>) are a replacement data table that contains replacement cycle data for the photosensitive drum 301, the developer in the developing device 307, and the fixing roller 332.

The addresses (4400 to 47FF) are a control timer table containing various timer values for performing printing operations, such as each process timing and paper feed timing.

106 is a RAM (random access memory), which is a working memory, and includes a timer (TIM) A as shown in FIG.

B, . . . , 11 paper size register (stores cassette size data based on signals from cassette size detection switches 320 and 324, which will be described later), status register 6, and other contents. The microprocessor
101 compares the cassette size stored in the paper size register with the size of recording information (image data, etc.) from an external device sent from the data control unit 2, and if the cassette size is larger, the subsequent stage Print control unit 100 of
It is designed to issue printing operation commands to the printer. Therefore, it is possible to print even if the printing paper is larger than the size of the information sent from the outside, and the usability can be improved. Reference numeral 107 is a non-volatile RAM, and the data in the memory is retained even when the power is cut off. Further, the data contents in the nonvolatile generation RAM are shown in FIG. 45(B). In FIG. 45(B), the address (6000) contains the drum characteristic number input from the operation unit in the exchange mode, and the address (6100) contains the jam information at the time of jam occurrence. It is used to prevent forgetting to dispose of jammed paper inside the machine when the power is turned off. address(
6200) is a paper discharge tray counter that counts the sheets in the reversing tray 381, and is incremented by 1 each time one sheet of paper is sent to the reversing tray 381. When this count value reaches a predetermined value, the tray becomes full and a message is displayed on the operation unit to prompt the operator to take out the paper from the tray. Further, the main paper discharge tray counter is automatically cleared when paper is removed from the tray by the operator. Therefore, even if the power is turned off, the number of sheets remaining in the tray is maintained by the book counter.

Address (6300) is a drum exchange counter, which counts up by 1 for each print. When the value of this counter reaches the value of the replacement table (drum) shown in FIG. 45(A), the operator is informed by the display on the operation section that the drum should be replaced.

The address (6400) is the developer exchange counter, which is incremented by 1 for each print as in the case of drum exchange, and when the value of this counter reaches the value of the exchange table (developer) in Fig. 45 (A) above. displayed on the operation panel.

Address (6500) is a fixing roller replacement counter, which is incremented by 1 for each printing as in the case of drum replacement, and when it reaches the value in the replacement table (fixing roller) in FIG. 45(A), it is displayed on the operation unit. .

108 is a power supply sequence circuit, and the non-volatile generation RA
It has the function of preventing erroneous operation when turning on or turning off the power of M107. 399 is a power supply device that supplies power to the control section. Reference numeral 110 denotes an input/output boat that outputs display data to the operation display section 111 and reads data on each operation switch. Reference numeral 112 denotes an input port for reading input data from each detector 113 in the print control section 100. 116 is a motor, high voltage power lamp, solenoid,
Drive elements such as fans and heaters are shown. 115 is a drive circuit for the drive element 116; 114 is a drive circuit for the drive circuit 1;
is an output port that provides an output signal to 15. 312 is a laser scan motor for operating the laser beam, 118 is a drive circuit thereof, and 117 is an input/output board that provides a drive control signal to the drive circuit.

344 is a semiconductor laser, 120 is a laser modulation circuit that performs optical modulation of the semiconductor laser, and 346 is a beam detector that detects the light beam operated by the laser scan motor, and a PIN diode that responds at high speed is used. There is.

121 is a high-speed comparator for digitizing the analog signal from the beam detector and creating a horizontal synchronization pulse; 119 is a high-speed comparator for digitizing the analog signal from the beam detector; This is a print data write control circuit that controls writing to the test pattern and generates test pattern print data. 122 is an interface circuit that controls output of status data to the data control section 2, reception of command data and print data from the data control section 2, and the like.

The details of the main blocks in FIG. 13 will be explained below. Figure 14 shows various detectors 11 in Figure 13.
FIG. 3 is a detailed circuit diagram of No. 3. In FIG. 14, signals from various detectors are input to a multiplexer 139. In the multiplexer, a select signal 831 causes an 8-bit signal S32 to be input to the input port 112 in FIG.

Reference numeral 320 denotes an upper cassette size detection switch, which is composed of four switches r'cK so that the combination of these switches represents the paper size. Reference numeral 324 denotes a lower cassette size detection switch, which has the same configuration as the upper cassette size detection switch. Reference numeral 319 is a cassette upper paper out switch, which is turned on when the cassette runs out of paper. 323 is a lower paperless switch. 123 is a pass sensor in front of the registration roller, and a CDS light receiving element is used. In this sensor, a bias voltage is applied through a resistor (not shown), and the output voltage changes depending on the presence or absence of paper. Therefore, by inputting the output to the comparator 124 to which the reference voltage Vre "1" is applied, a signal for determining the presence or absence of paper can be obtained.

Reference numeral 326 indicates a manual feed switch for detecting paper from the manual feed guide 325, 336 indicates a paper ejection switch located on the fixing roller section, and 395 indicates a paper ejection switch located on the paper ejection tray section. Reference numeral 125 indicates a toner out detection switch for detecting the absence of toner in the toner box, and 126 indicates a toner full detection switch 1' which operates when the toner bag is full of toner.

Reference numeral 127 is a sensor for detecting the specific toner concentration of the developer (probe concentration detection sensor), and a photodiode is used. A bias voltage is applied to this sensor via a resistor, and the output voltage changes depending on the toner concentration. Therefore, by inputting the output to the comparator 128, since the reference voltage Vref 2 is applied to the other input terminal of the comparator 128, a signal of 1 or O is obtained when the toner concentration is above or below the specified value, respectively.

129 is 0N10FF by opening and opening the front cover.
130 is a temperature fuse provided in the fuser, 131 is a drive type 'IIA (+24VB)
) is an MC relay that turns 0N10FF. Since one side of the altitude fuse 130 is connected to the +24VA power supply, if the temperature fuse 130 is blown due to an abnormality in the fixing device, the MC relay 131 is turned off and the driving power is turned off. Moreover, the temperature fuse 130 is a resistor RO
1, and one side of the resistor RO1 is connected to the resistor RO2 and the input of the comparator 132. Further, a reference voltage Vref3 is applied to the other input of the comparator 132. Therefore, when the temperature fuse 130 blows, the input of the comparator 132 becomes Ov. Therefore, the comparator 132 outputs a temperature fuse blowout detection signal. Reference numeral 133 denotes a destination selector switch. Specifically, this switch is set to 0N10FF, so that the ON state is for domestic destinations (A and B sizes), and the OFF state is for U.S. destinations (legal and letter size). Therefore, for example, even if the code combinations of the upper or lower h set size switches (4 pieces) are the same, either the domestic or US paper size is selected depending on the state of this switch.

134 is a jam reset switch, which is installed inside the front cover. This switch is a switch that is turned ON for confirmation after the operator calls for a paper jam or full toner, after the operator clears the jam or replaces the toner bag. Therefore, unless this switch is turned ON after the above processing, the display of jam or full toner on the operation panel will not be cleared.A392 is a paper discharge tray sensor in FIG. 5 that detects the paper in the tray. A thermistor 334 detects the temperature of the fixing device, and is controlled so that the temperature detected by this thermistor is constant. Thermistor 33
The output of 4 is connected to the resistor RO3 and the input sides of comparators 136 and 137. Therefore, the input voltage of the comparator changes as the resistance value of the thermistor 334 changes due to temperature.

That is, as the temperature increases, the input voltage increases.

The other input terminal of the comparator 136 has a resistor RO6
A voltage divided by RO7 is applied, and the output of the comparator 136 changes depending on whether it is higher or lower than the divided reference voltage. Also, resistors RO6 and R
A resistor RO8 is connected to the connection point of O7, and one end of the resistor RO8 is connected to the collector of the transistor 138. Therefore, when this transistor 138 is turned on by the input signal (power save signal) 83, the comparator 136
The reference voltage of is lowered by resistor RO8, and the temperature control of the fuser is lower than when transistor 138 is at 0FFL. Therefore, the power consumption of the fixing device becomes low and the fixing device enters a power save state. Also, comparator 137
The reference voltage is given by the voltage division of resistors RO4 and RO5. Since the reference voltage of the comparator 137 is set much lower than the reference voltage of the comparator 136, it is possible to detect a temperature drop in the fixing unit due to heater disconnection or failure of the heater drive circuit during printer operation. . and output 8 of comparator 136
33 is input on one side to the multiplexer 139 and is read by the microprocessor-101. Note that this input signal is used to detect the ready state of the fixing device. The other signal is used as a drive signal for the fixing device heater lamp 333 in FIG.

342 is a drum temperature sensor that detects the temperature near the photoreceptor 301. The output side of thermistor 342 is connected to resistor R58 and the input of operational amplifier 270. Therefore, the resistance value of the thermistor 342 also changes depending on the temperature change near the photoreceptor 301. Therefore, operational amplifier 2
The input voltage of 70 also changes. The operational amplifier 270 outputs a low voltage when the temperature of the photoreceptor 301 is low, and a high voltage when the temperature is high. operational amplifier 2
70 is a voltage follower, and its output is
It is connected to the input of the A/D converter 271. Then, the output voltage of the operational amplifier 270 is converted into a digital value by the A/D converter 271 and read by the microprocessor 101 through the multiplexer 139. This A/D converted temperature data of the photoreceptor 301 is used for charge correction of the photoreceptor 301, which will be described later. 440
441 is a cassette/manual feeding adjustment switch, and 442 is a top margin adjustment switch.

FIG. 15 is a detailed block diagram of the drive circuit 115 and output element 116 in FIG. 13. In FIG. 15, 141 is a developer motor, and a DC-driven Hall motor is used. Reference numeral 140 is a driver for the developer motor, which performs PLL control. 143 is a fixing device motor, and a DC-driven Hall motor is used.

142 is a driver for the fuser motor 143;
Performs PLL control. 145 is a fan motor for cooling the inside of the machine, and a DC-driven Hall motor is used. 144 is a driver for the cooling fan motor, which is a PLL like the developer and fuser driver described above.
No speed control is performed. 147 is the photosensitive drum 30
1 drive motor, and uses a 4-phase pulse motor. 146 is a driver for the drum motor 147, which employs a constant current 1-2 phase excitation force type. The speed is approximately 1200 PPS, which is the speed at which vibrations are less likely to occur. 149 is a registration motor that drives the registration roller 329 and manual feed roller 327, and is a pulse motor. 148 is a driver for the registration motor, which uses a constant voltage two-phase excitation system. The speed is 40
It is about 0 PPS.

Note that when the registration motor 149 rotates in the normal direction, the registration roller 329 rotates, and when the rotation direction is reversed, the manual feed roller 327 rotates. These are transmitted via a one-way clutch.

151 is a lower paper feed roller 322 and an upper paper feed roller 3
The paper feed motor that drives 18 is a pulse motor. As above, pressure and reverse rotation are transmitted via a one-way clutch. Reference numeral 150 denotes a driver for the paper feed motor 151, which uses constant voltage two-phase excitation similarly to the registration motor driver 148. The speed is about 400PPS.

Reference numeral 302 denotes a static elimination lamp that removes residual charges on the photoreceptor 301 before charging, and is composed of a plurality of red LEDs. R10 is a current control resistor for the static elimination lamp 302, and 152 is a driver for the static elimination lamp 302.

A pre-transfer static elimination lamp 303 is placed in front of the transfer charger to increase transfer efficiency, and is composed of a plurality of red LEDs. R11 is a current control resistor for the pre-transfer static elimination lamp, and 153 is a driver for the pre-transfer defrosting lamp. Reference numeral 158 denotes a solenoid for a toner collection blade, and when this solenoid is turned on, the blade 310 is pressed against the photoreceptor 301. 154 is a driver for the blade solenoid 158. Reference numeral 159 denotes a toner replenishment motor for replenishing toner from the toner hopper to the developing device 307, and as this toner replenishing motor rotates, toner is replenished from the toner hopper to the developing device 307. The operation of the toner supply motor 159 is performed according to the output of the prologue concentration detection sensor shown in FIG. 14. 155 is a driver for the toner supply motor 159. 131 is an MC relay that operates in conjunction with the door switch similar to that shown in FIG. 14, and 156 is its driver. Then, as shown in Fig. 15, M
The power side common for the motor, lamp, etc. that excludes the C relay 131 is connected to the contact 163 of the MC relay 131, and the other contact is connected to the +24VB power supply.Therefore, when the MC relay 131 is ON, the motor and the lamp can be operated.

304 is a charger for charging, and the case of the charger is connected to the ground of the aircraft body.

The corona discharge wire of the charger is connected to the high voltage power supply 338.
is connected to the output terminal of the charging high voltage power supply 160,
An 0N10FF signal line 835 for high voltage output and an analog control signal line 836 for changing the high voltage output current are connected to the input of the high voltage power source for charging. Further, the analog control signal line 836 is connected to the D/A converter 165,
Data from the charging voltage control data line 837 from the microprocessor 101 is converted into an analog voltage by the D/A converter 165 to control the output current of the charging high voltage power source. Reference numeral 306 denotes a peeling charger, and the scraping charger 306 is connected to the output of the high voltage power source 161 for peeling. The high-voltage power source for peeling has an AC output.

Reference numeral 305 is a transfer charger for transferring the developed toner on the photoreceptor 301 onto a sheet of paper, and the transfer charger is connected to the output of the high-pressure N source 62 for transfer. In addition to the transfer charger output, the high-voltage transfer power source also incorporates a developer bias power source, and its output line 838 is connected to the developer magnet roller 308. This voltage applies a bias voltage to the magnet roller 308 to provide a developing bias. 33 is a heater lamp of the fixing device, one side of which is connected to one of the power sources of the ACI OOV.

The other end is connected to the second contact 164 of the MC relay 131, and the other end is connected to the heater drive circuit 166. Therefore, the heater lamp 333 is connected to the MC relay 1.
It operates only when 31 is ON. Also, heater drive circuit 1
Two input signals 833 and 839 are input to 66, and S33 is the thermistor 33 in the fixing device shown in FIG.
4, which is a density control signal for the fixing device. S
39 is a forced OFF signal for the heater lamp 333 from the microprocessor-101.

Figure 16 shows the laser scan motor 3 in Figure 13.
12 and its driving circuit 118. FIG. 16th
In the figure, 312 is a circuit diagram inside the laser scan motor. LO2, 103, and LO4 indicate motor coils, and 180, 181, and 182 are Hall elements that detect the position of the motor rotor, respectively. 183,18
4.185 is a comparator for the Hall elements 180, 181, 182, and its output is connected to the base of the power transistor 173, 172. It is connected through R27 and R26. Further, the power transistors 171, 172, 173
Between the base and emitter of is a base resistor R23, R
24 and R25 are connected to each other. As the rotor of the motor rotates, the ball elements 180, 181°18
2 turns on in the order of 180, 181, 182 (7). Therefore, the comparator 183.184, 185 (7) output also becomes 183, 184.185 (7) [LOWL/bell. Therefore, the power transistor is 173°172.171
(The laser scan motor 312 rotates by applying the driving voltage in the order of '0102.LO3°LO4 to DMk-ON.The output of the comparator 185 is passed through the diode DO2 to the resistor R30, the capacitor CO6, and the inverter 174. The output terminals Q1 and Q2 of the frequency dividing counter 175 are connected to the motor speed switching gates 177 and 176, and the outputs of the speed switching gates are connected to the motor speed switching gates 177 and 176. passes through OR gate 178 to PL
L (phase, lock, loop 1) control IC17) FG
Large input is connected. Here, it is assumed that the output terminal Q1 outputs a frequency obtained by dividing the input signal by four, and the output terminal Q2 outputs a frequency obtained by dividing the input signal by eight. Further, the output of the speed control signal line 840 and its inverted output are connected to one input of the speed switching gates 176 and 177. Therefore, when 840 is at the LOW level, the switching gate 177 is enabled, and the output of 01 of the frequency dividing counter is input to the FG of the PLL control IC 167, and S40 goes high.
When the level is IGH, the switching gate 176 is enabled,
The Q2 output of the frequency dividing counter 175 is the PLL control IC 167
FG large input is input. Note that the speed control signal line 840 is connected to the data control section 2.

The signal on the speed control signal line 840 specifies the frequency division ratio of the frequency division counter 175, and serves as a frequency division ratio designation signal. Furthermore, in this sense, the data control section 2 that outputs this frequency division ratio designation signal serves as speed setting means.

The data control unit 2 includes a timer (timer F, which will be described later), which is a timing means that starts counting after the printing operation is completed.
Equipped with: When no print information is input from an external device even after the timer has exceeded a certain time, the output of the speed control signal line 840 is set to HIGH.
It is designed to change from H level to LOW level. Next, to briefly explain the input/output signals of PLLIIJIllIC167, the P/S terminal (PLAY/5
TOP) stops at HIGH level and starts at LOW level. AGC at HIGH level.

The outputs from both terminals of the APC are at IIGH level.

FGIN is a rotary motor pulse signal input from the motor to be controlled, N1. N2 is the signal that switches the frequency division number of the reference frequency divider inside this IC, 33/45 is the motor rotation speed switching signal, CPOLIT is the crystal reference frequency division output signal, CPIN is the reference frequency input, L[) is When the rotation speed of the motor is within the lock range in the lock detection signal, a HIGH level is output, otherwise an OW level is output. AFC is the output of the motor's speed control system and is the output of the 8-bit D/A converter inside the PLLIC. APC is the output of the motor's phase control system and is the output of the PLLI.
This is the output of the 8-bit D/A converter inside C. Also P
×01 connected to LL IC167 is a crystal oscillator for reference frequency generation, COl.

GO2 is an oscillation capacitor.

The output terminals of AFC and APC of PLL control 10167 constitute an adder circuit with resistors R12 and R13, and operational amplifier 16.
It is connected to one side input terminal of 8. operational amplifier 168
A voltage obtained by dividing +12V by resistors R14 and R15 is applied to the + side input terminal of the switch. Further, a negative feedback circuit is formed by the resistor R16 and the capacitor CO3, and the capacitor CO3 in particular functions as a bypass filter. Therefore, the amplification degree of the operational amplifier 168 is such that it has a characteristic of attenuating inputs having a certain frequency or higher. operational amplifier 16
The output of 8 is a pulse width modulation switching regulator I.
It is connected to the ten input terminal of C169. 169 is a commercially available pulse width modulation switching regulator IC.
It is. This IC 169 and power transistor 170. The die A-DOI, the coil LO1, and the capacitor CO5 constitute a down switching regulator circuit. In the input/output of the IC 169, one terminal is a comparison reference voltage terminal, and a reference voltage obtained by dividing the voltage of the reference voltage output terminal VREF inside the IC 169 by resistors R17 and R18 is applied. The DEADT IME terminal regulates the maximum pulse width of the output, and connects the VREF to the resistors R19 and R.
A voltage divided by 20 is applied. C1,C
2 is an output terminal, and the pulse width changes depending on the voltage value of the input terminal. That is, when the + side input terminal voltage is lower than the one side input terminal voltage, the pulse width of CI and C2 on the LOW level side becomes small, and the width in which the power transistor 170 is turned on also becomes small.

Therefore, the voltage across the capacitor CO5 also becomes smaller.

Moreover, when the + side input terminal voltage is higher than the one side input terminal voltage, contrary to the above, the pulse width of C1 and C2 becomes large, and the voltage across the capacitor CO5 also becomes large.

The rotation speed control of the scan motor 312 will be explained below.

When the rotation start signal S42 of the scan motor 312 reaches the OW level, AFC and AP of the PLL control IC 167
Since the Ryokawa power of C is at the LOW level until the above-mentioned lock signal S41 is output, the operational amplifier 168 outputs a voltage of 1-11GI-Level. Therefore, the output pulse width of the regulator IC169 becomes large, and the voltage across the capacitor CO5 becomes about +16V. Since any one of the Hall elements 180, 181, 182 is turned on at the position where the motor rotor is stopped, motor coils LO2, L03, LO4
Among them, the coils corresponding to the Hall elements 180, 181, and 182 are excited, and the scan motor 312 starts rotating. The scan motor 312 then speeds up its rotation.

Since the level of the speed control signal line 840 is now HIGH, the Q2 output of the frequency division counter 175 is
It is applied to the FG input terminal of control 10167. Therefore, the frequency division counter 175 functions as an 8 frequency division circuit. FG
When the frequency of the signal applied to IN reaches approximately 96% of the reference frequency inside the PLLIC 169, the lock signal 841 of the LD terminal becomes HIGH, and the AFC and APC output levels are not fixed at the LOW level (OV) but are set to the PLLIC internal D/
Switched to the output voltage of the A converter. Therefore, from now on,
The scan motor 312 is controlled to a constant speed by the fast trace control system output AFC and the phase control system output APC.

Further, in this embodiment, when a print command is not received from the data control section 2 for a certain period of time (approximately 5 minutes), the scan motor enters a standby state and the output of the speed control line S40 becomes LOW level. Therefore, the frequency divider 175
Since the frequency is divided by 4, the scan motor is 4/8
In other words, the rotation speed becomes 1/2. This is to perform half-speed control as described above in order to prevent problems with reliability of the motor's bearings, etc., from occurring if the motor rotates at high speed for a long period of time. In this embodiment, the pressure is approximately 12.0OOrpa+ during printing operation, that is, during high-speed rotation, and approximately 60 during standby.
00 rEllll.

FIG. 17 is a detailed circuit diagram of the laser modulation circuit 120 and semiconductor laser 344 in FIG. 13. In FIG. It consists of a monitoring photodiode 260 which is a photodetection means for monitoring the output beam intensity. Reference numeral 257 is a high-frequency transistor serving as a current converting means (or first current driving means) for optically modulating the laser diode 259. The resistor R50 is a current detection resistor, 25B is a transistor serving as a second current driving means for passing a bias current to the laser diode 259, R51 is a current limiting resistor thereof, and R52 is a base current limiting resistor of the transistor 258. 254, 25
5.256 is a high-speed analog switch for modulating the laser diode 259, and each analog switch has a low voltage between the drain (D) and source (S) when a HIGH level voltage is applied to the gate (G). It becomes a resistance and turns on. LOW level voltage is gate (G)
On the other hand, when the voltage is applied to the voltage, the resistance becomes high and the voltage becomes OFF. The output power from the laser 259 has three levels in this laser printer. First, the laser diode 25 is turned on by turning on the analog switch 254 with the output P (ON) in order to almost completely remove the charges on the photoreceptor 301 in a portion corresponding to the white background on the paper.
9 is the output P (ON).

The second part corresponds to the black background on the paper, and is located on the photoreceptor 301.
In order to leave the electrical charge on the top as it is, the analog switch 2
By turning on 56, the laser diode 259
becomes output OFF, that is, P(OFF). The third one is for increasing the print density of one dot line with the output P (SH) between the first output P (ON) and the second output P (OFF), and by turning on the analog switch 255. The laser diode 259 outputs the output P(S
H) (Details of P (SH) will be explained later)
.

Resistors R42 and R43 are analog switches 254°255
．． Short circuit protection resistance when changing 0N10FF of 256, 249
, 250, 251 are the analog switches 254, 25
5.256 gate driver. CO9,010
, C11 is a speed-up capacitor, R47,
R48 and R49 are the gate drivers 249 and 250
．． 251 input resistance.

246 is a 3NAND gate, and when all three gate inputs become HIGH level, the output becomes LOW level, turning on the analog switch 254, and the laser diode 259 becomes in the output P (ON) state. 3
The first of the two input gates is connected to the output of the inverter 253, and the input of the inverter 253 is connected to the print data signal 547 (1-11G) (low level for printing at level, no printing). The second one is connected to the output of the inverter 252 and is connected to the output of the inverter 252.
The input of is connected to a shadow signal 848 (shadow on at HIGH level, off at LOW). The third is connected to a laser enable signal 549 (laser enable at HIGH level, laser forced OFF at LOW level). Therefore, the output of the NAND gate 246 is L.
The condition for reaching the OW level is when the laser enable signal 34
9 is HIGH, the shadow signal 848 is LOW, and the print data signal 847 is LOW. Next, 247 is 3N
When all three gate inputs of the AND gate become HIGH level, the output becomes OW level, turning on the analog switch 255 and turning on the laser diode 25.
9 is in the output P (SH) state. The first of the three input gates is connected to the shadow signal 848, and the second is connected to the inverter 25, which is the inverted signal of the print data signal 347.
3, the third is the laser enable signal 849
are connected to each. Therefore, the conditions under which the output of the NAND gate 247 becomes LOW level are when the laser enable signal 849 is HIGH, the shadow signal 848 is HIGH, and the print data signal S47 is LOW. Next, 248 is a 2OR gate, and when one of the two gate inputs becomes LOW level,
The output becomes OW level, and the analog switch 25
6 is turned ON, and the laser diode 259 becomes OFF state output P (OFF) state.

245 is a sample and hold IC, which converts the output of the laser diode 259 into the shadow output P(SH
) is used to control

ANALOG-INPLJT is the analog voltage input to sample, SAMPLEC is the hold capacitor CO8
The connection terminal 5TROBE is a sampling strobe signal terminal and is connected to the sample strobe signal 346. Reference numeral 237 is an operational amplifier having an FET input, and constitutes a voltage forwarder circuit. DO3 is a Zener diode that regulates the output of laser diode 259 to be within the maximum rating. Also, the resistor R40 and capacitor CO7 constitute an integrating circuit, and the resistor R41
is a discharge resistance that discharges the charge of the capacitor CO7 at a constant rate. 236 is an analog switch whose gate (G) is connected to a buffer y244, and the sample signal S45 is input to the input of the buffer 244. 253 is a transistor for level conversion, and R39 functions as a current limiting resistor when charging the capacitor CO7. R38 is a base current limiting resistor of the transistor 235, and 234 is a comparator serving as comparison means. This comparator has a hysteresis characteristic due to the action of resistors R34 and R35.

] The output voltage of the laser monitor amplifier N232 is applied to the input side of the amplifier 234 through the resistor R34. 232 is an amplifier for the output of the photodiode 260 that detects the optical output from the laser diode 259, and serves as current-voltage conversion means. Resistor R32°R33, VROI is the operational amplifier 23
This is a resistor that regulates the degree of amplification. Therefore Polycomb V
By changing R01, the amplification degree of the operational amplifier 232 can be changed. R31 is an output load resistance of the photodiode 260 in the semiconductor laser 344, and a voltage proportional to the output current of the photodiode 260 is obtained. Optical output P of photodiode 260
The relationship between short circuit current 1s (F) and O is shown in FIG.

In FIG. 19, is indicates the monitor current, and PO indicates the optical output of the laser diode 259. The output of P(ON) is approximately 6iw, the output of P(8)() is approximately 4mw, and the output of P(O
FF) is set to O. Also, LA-A and LA-B are 2
It represents the monitoring characteristics of a street laser diode. Normally, the volume VRO1 is adjusted so that the output voltage of the operational amplifier 232 is about 3.5 mW when the laser diode optical output is 5 mW. Therefore, the characteristics of both graphs LA-A and LA-8 in FIG. 19 can be adjusted by the volume VROI.

238 is a comparator for checking whether the laser diode 259 is emitting light, and the output voltage of the operational amplifier 232 is applied to the + side input. Also-
A voltage divided by resistors R36 and R37 (in this case, it is set to 2.0 mm) is applied to the side.

Therefore, the laser diode 259 emits light, and its output is about 2111 W bell, which changes from LOW level to HIGI-(
The level changes and a laser ready signal 843 is output. Further, a laser light amount setting voltage is applied to one input terminal of the comparator 234. The set voltage is given from either analog switch 240 or 241. That is, the analog switch 240 is turned ON when the laser output P (ON) is set, and the output voltage of the voltage follower 239 is applied to one side input of the comparator 234. A voltage divided by a main exposure adjustment volume 360 and a resistor R45, which is a first voltage variable means, is input to the input terminal of the voltage follower 239.
By varying 0, the voltage at one terminal of the comparator 234 also changes. Further, the analog switch 241 is turned on when the laser output P (SH) is set, and the output voltage of the voltage follower 239 is connected to the resistor R46 and the second
A shadow exposure adjustment volume 36 is a voltage variable means for
A voltage divided by 1 is applied to an example input terminal of the comparator 234. The above voltage follower 239, analog switches 240, 241, main exposure adjustment volume 360. Resistor R45, shadow exposure adjustment volume 361. The resistor R46 constitutes a light output setting means. Further, a circuit that compares the voltage detected by the monitor photodiode 260 and amplified by the monitor amplifier 324 with a set voltage by the comparator 234, and integrates the comparison value is referred to as an optical output stabilizing means.

The analog switches 240 and 241 are switched by a main exposure setting signal 844. That is, when the main exposure setting signal S44 is at a LOW level, the output level of the inverter 242 becomes a HIGH level, and the analog switch 241 is turned on. Further, when the main exposure setting signal 844 is at HIGH level,
The output of the buffer 243 becomes HIGH level and the analog switch 240 is turned on. Also, analog switch 2
40.241 output (S side) is voltage follower 2
61, and the output 850 of the voltage follower 261 is used to correct the threshold level of the horizontal synchronizing pulse detection comparator of the beam detection circuit, which will be described later.
is used.

Next, the current-output characteristics of the laser diode used in this printer will be explained. Figure 18 is I
It is a graph of F-PO characteristics. TC=0℃ is the IF-Po characteristic when the temperature of the laser diode 3440 case is 0℃,
Same < TC=25℃, when case temperature is 25℃, TC=50
°C is the IF-PO characteristic when the case temperature is 50 °C. Taking the characteristic of case temperature TC=25° C. as an example, when the current IF flowing through the laser diode 259 is gradually increased from O, the optical output PO starts to be output from a point of about 50 mA. Then, at the point of IF=68mA, the P(ON
), which is the optical output of 6111W.

Therefore, even in the case of TO-0°C, the optical output PO starts to be output at a point of about 40+nA, so by turning on the transistor 258, the bias current is always maintained when the laser enable signal 849 is at a HIGH level. IFB is supplied to reduce the power loss of the laser modulation transistor 257. Therefore, the operation of the laser modulation transistor 257 is guaranteed to be extremely stable even at high temperatures due to the action of the bias current IFB. In addition, if the amount of change in current required to modulate the laser is, for example, TC = 25°C, the value of lF25 - IFB should be used.Compared to directly driving the current of lF25 with the transistor 257, the light intensity stabilization will be described later. The accuracy of the movement can be improved considerably. Furthermore, as is clear from the graph, the output of the laser diode itself varies considerably depending on the temperature, so the light amount stabilizing circuit is required. In this laser light amount stabilizing circuit, the light amount from the laser diode 259 is detected by a monitor photodiode 260, and the short circuit current Is of the photodiode 260 is controlled so as to always be a constant amount. This is because, as is clear from FIG. 19, the monitor short-circuit current IS and the optical output PO of the laser diode 259 are in a perfect proportional relationship, so the monitor current I
If s is kept constant, the optical output PO is always kept constant. Furthermore, since the temperature-related drift of the photodiode 260 is very small, even if the temperature changes, the amount of change in optical output can be ignored. Next, the operation of the above-mentioned optical output stabilizing circuit will be explained using FIGS. 17 and 20.

In FIG. 20, when the laser enable signal S49 and the sample signal 845 both reach 1"I G l- level, the transistor 258 in FIG. 17 is turned on, and a bias current (approximately 30 mA) flows to the laser diode 259 through the resistor R51. .

Also, at this time, since the print data signal 847 and the shadow signal 848 are both at LOW level, the gate 2
Among the analog switches 254, 247, and 248, the inputs of only the gate 246 are all at HIGH level, so the output is at LOW level, and the analog switch 254 among the analog switches 254, 255, and 256 is turned on. Furthermore, when the sample signal S45 becomes 1-1rGH, the analog switch 236 is turned on. At this time, since the capacitor CO7 is not yet charged, the output of the operational amplifier 237 is Ov, and the base of the laser modulation transistor 257 is also Ov. Therefore, at this point, only the bias current flows through the laser diode 249, and the laser diode does not emit light, as can be seen from the characteristics shown in FIG. Since no laser is emitted from the monitoring photodiode 260 of the laser diode, the monitor current is is O, and since the output of the amplifier 232 is Ov, the output of the comparator 234 is at a LOW level. Transistor 235 is turned off.

Since the transistor 235 is OFF, the capacitor CO
7 is charged through resistors R39 and R40. The time constants of the resistors R39 and R40 and the capacitor CO7 during charging are selected to be about 20 to 50 msec. If this value is very small, the response of the stabilizing circuit will be too fast, and the fluctuations in the optical output level of the laser will become large. Moreover, if it is too large, the responsiveness will deteriorate and it will take time for the optical output to stabilize. As the capacitor CO7 is charged, the output voltage of the voltage follower 237 also gradually increases. Therefore, the laser modulation transistor 2
As the base voltage of 57 increases, current flows through the collector. At this time, the collector current 1c of the transistor 257 has a current value of (VB-VBE(SAT))/R50. The laser diode 259 receives the bias current IFB from the transistor 258 and the transistor 2.
An additional current IF with the current 1c from 57 flows. Then, the current 1c increases and the 7th turn of the laser diode 259
The laser diode 259 emits light when the current IF reaches approximately 50+n A (TC=25° C.). When the laser diode 259 emits light, the monitor current of the monitor photodiode 260 flows in accordance with the emitted light output, and the voltage at the ten terminals of the operational amplifier 232 increases, and the output voltage also becomes a value obtained by amplifying the input voltage. is output. Since the amplification degree of the operational amplifier 232 is adjusted in advance by the volume VRO1 so that the output voltage of the A bare amplifier 232 is approximately 0.5V with respect to the output How of the laser diode 259, the optical output of the laser diode 259 increases to approximately 2+11W. , when the output voltage of the operational amplifier 232 reaches approximately 1V, the output signal of the comparator 238, that is, the laser ready signal 343
changes from LOW to HIGH level. The main exposure setting signal 8 is input to one side input terminal of the comparator 234.
44 is at LOW level, a shadow exposure level (light output P(SH)) voltage is applied through the analog switch 241. This voltage is set according to the sensitivity characteristics of the photoreceptor 301, and the shadow exposure level voltage is set by a shadow exposure setting volume 361 in the operation section. now,
Voltage corresponding to an average optical output of 4 mw2. Ov
Suppose that Therefore, the optical output of the laser diode 259 increases, and the voltage at the input terminal of the comparator 234 increases to 2.
When the voltage exceeds 0■, the transistor 235 is turned on and the capacitor CO7 is discharged through the resistor R40. Therefore, the base voltage of the laser modulation transistor 257 also decreases, and the optical output of the laser diode 259 decreases to 4.
It becomes less than mw. When the optical output of the laser diode 259 becomes 4 mW or less, the voltage at the + side input terminal of the comparator 234 also becomes 2. When the voltage becomes lower than OV, the transistor 235 is turned off again.

Then, the capacitor CO7 is charged up again through the resistors R39 and R40. Then, the laser diode 259 again changes its optical output around 4n+w, and the comparator 234 repeats the 0N10FF operation at a constant cycle. Incidentally, since this comparator 234 has a hysteresis characteristic, the comparative judgment becomes stable and reliable judgment can be made. And the resistance R
39 and R40, the capacitor CO7
The voltage across the terminal approaches the value ①o1 in FIG. 20 and becomes stable.

After the laser ready signal 843 becomes HIGH level, the microprocessor 101 outputs a shadow level sample strobe signal 846 after a predetermined time t6 has passed through the output port. When the sample strobe signal is output, the sample hold IC 245
The voltage VO1 (FIG. 20) of the capacitor CO7 input to the NALOG-INPUT input terminal is sampled and held, and the voltage is stored in the hold capacitor CO8. Therefore, after the sample strobe signal is turned off, the control voltage VO for outputting the shadow level P (SH) is applied to the output 0LJT of the sample and hold IC.
1 continues to be output.

Next, when the sample hold operation for the shadow level P(SH) is completed, the microprocessor 101 switches the main exposure setting signal S44 to the HIGH level through the output port. Therefore, the output voltage of the voltage follower 239 is applied to one input terminal of the comparator 234 through the analog switch 240. Voltage follower 2
The main exposure level (light output P (ON)
) voltage is being output. This voltage is adjusted according to the sensitivity characteristics of the photoreceptor 301 by the main exposure setting knob 3 in the operation section.
Assume that the voltage set by 60 is currently outputting a voltage of 3.0 cm, which corresponds to an average optical output of 5 mw. Therefore, the output of the comparator 234 is LOW because the input terminal on one side is switched to 3.0■.
level, and the transistor 235 is turned off.

Therefore, as the capacitor CO7 is further charged up, the base voltage of the laser modulation transistor also increases, and the optical output of the laser diode 259 also increases.

When the optical output of the laser diode 259 becomes around 6+nW, the output voltage v232 of the operational amplifier 232 becomes about 3V. When the output voltage of the operational amplifier 232 becomes 3■ or higher, the output of the comparator 234 changes to HIG)-1 as in the case of setting the shadow level described above, and the transistor 23
5 is turned on, and capacitor CO7 is discharged through resistor R40. Therefore, the base voltage of the laser modulation transistor 257 also decreases, and the optical output of the laser diode 259 becomes 5+nw or less. When the optical output of the laser diode 259 becomes 6 mW or less, the voltage at the + side input terminal of the comparator 234 also becomes 3.0 ■ or less, and the transistor 235 is turned off again. Then, the capacitor CO7 is charged up again through the resistors R39 and R40, and the optical output of the laser diode 259 is 5mW.
That's all.

In this way, the comparator 234 repeats the 0N10FF operation at a constant cycle when the optical output of the laser diode 259 is around 6 mW. And the resistors R39 and R40
Due to the integral effect of
It becomes stable as it approaches figure VO2. When the setting of the main exposure level is completed, the microprocessor-01
The operation of a sunblink timer, which will be described later, is started to write print data to the photoreceptor 301. The sample timer is triggered one after another at a constant period T each time a laser beam detection signal, which will be described later, arrives, and outputs the sampling signal 845 only in a portion other than the print data write operation, that is, in the period shown in FIG. 20a. And print data 8
47 and shadow data 848, the sample signal 845 is at the OW level, so the analog switch 236 is turned off. Therefore, in the print area where the laser diode 259 is modulated by the print data D47 and the shadow signal 848, the optical output level of the laser diode 259 is P(ON), P(SH
), P (OFF). That is, firstly, when the print data signal S47 is OFF, that is, LOW level, and the shadow signal is OFF, that is, LOW level (the printing output is white), the NΔAND gate 246 is established, and only the analog switch 254 is turned ON, and the modulation signal is turned on. The main exposure level voltage VO2 is applied to the base of the transistor 257, and the laser diode 25
The optical output of No. 9 is P(ON)=6 mw. The second case is when the print data signal 847 is OFF and the shadow signal is ON (
The printing output is halftone) and NAND
The gate 247 is established, only the analog switch 255 is turned on, the output voltage VO1 of the sample and hold IC 245 is applied to the base of the modulation transistor 257, and the optical output of the laser diode 259 becomes P(SH).
=4 mw. Third, the print data signal 847 is ON,
When the shadow signal is OFF (the print output is black), the OR gate 248 is established and only the analog switch 256 is turned ON. Therefore, the base of the modulation transistor 257 is shot to GN() and becomes O■, so the optical output of the laser diode 259 is P(OFF)=
It becomes 0 and does not emit light. In this manner, the first printing is performed. When printing is finished, the microprocessor
101 is the main exposure setting signal 844 through the output port
is set to LOW level again, and the shadow exposure level P (SH
). Therefore, the voltage at one side input terminal of the comparator 234 becomes 2.0V, which is the setting voltage of the shadow exposure level. Therefore, the °c transistor 235 is turned on, the capacitor CO7 is discharged, and vco7 becomes smaller. In order to explain the optical output stabilization operation of the laser diode, it is assumed that the case temperature of the laser diode 344 increases by ΔT during the second printing operation. As is clear from the characteristic diagram in Figure 18, as the case temperature increases, the IF-Po characteristic curve of the laser diode shifts to the right, and when the same current is passed through the laser diode 259, the optical output po decreases. I end up. Therefore, in order to obtain the same optical output, I
F must be increased by the current ΔIF corresponding to the shift of the characteristic curve to the right. Therefore, the voltage VCO7 of the capacitor CO7 is higher than the first set voltage v01 by the above △IF.
The optical output of the laser diode 259 is set to P (SH) = 4 mw, which is the same as the first setting. and the first
Similarly to the second time, the sample strobe signal 846 causes the sample hold IC 245 to output the shadow exposure level P(
ON) is set. At this time as well, the operation corresponds to the temperature characteristics of the case of the laser diode 344, and the voltage of the capacitor 007 is set to VO4, which is higher by the correction voltage Δv2 due to the temperature rise, and after setting, printing is performed on the second row of the cylinder. In this way, the shadow exposure level P (
SH) and the main exposure level P(ON) are very accurately maintained at constant levels by the function of the stabilizing circuit, thereby making it possible to perform high quality printing. Incidentally, as described above, the main exposure level P (ON) performs a light amount stabilizing operation so that the light output is always kept constant except when printing data is being written. Furthermore, for the shadow exposure level, a sample bold operation is performed before the start of printing of each character, and unlike the main exposure level, a light amount stabilization operation during the print writing operation is not performed. This is because the circuit becomes complicated and expensive, and the shadow level is an auxiliary element compared to the fluctuation of the main exposure level, so even if it fluctuates a little, it does not have much effect on the print quality. In addition, when changing the setting voltage input to the comparator 234 according to the sensitivity characteristics of the photoreceptor 201, the adjustment is made by changing the main exposure setting volume 360. This main exposure setting volume 360 is adapted to vary the input voltage of the voltage follower 239. Therefore, by varying this main exposure setting volume 360, the light output setting voltage when P(ON>) can be adjusted. On the other hand, the light output setting voltage when P(S)() Resistor R46 and shadow exposure setting volume 3
61. Therefore, by adjusting the main exposure setting volume 360, P(ON
), the optical output setting voltage at P (SH) changes proportionally, and a constant relationship between recording density and applied voltage can be maintained. Therefore, when P(ON) as in the conventional case,
Adjustment is simplified without requiring the complicated operation of varying and adjusting the set voltage at the time of P(SH).

FIG. 21 is a detailed circuit diagram of the beam detection circuit 121 and beam detector 346 in FIG. 13.

In FIG. 21, 346 is a beam detector that uses a PIN diode with very fast response. Further, this beam detector 346 is connected to the photoreceptor 301 as shown in FIG.
The pulse width and pulse generation position must be extremely accurate.

Therefore, if the pulse width, pulse generation position, etc. vary with each beam scan caused by the rotation of the polygon mirror 313, the writing start point on the photoreceptor 301 will vary, resulting in poor print quality. The anode side of the beam detector 346 is connected through a load resistor R52 and a resistor R55 to one side input terminal of a high-speed comparator 262, which is a comparison means. In addition, the + side input terminal of the comparator 262 has resistors R53 and R5.
A voltage divided by 4 is applied through the resistor R56. Further, a capacitor C12 for noise removal is connected in parallel to the resistor R54. Further, R57 is a positive feedback resistor for providing hysteresis characteristics, and C13 is a feedback capacitor for applying feedback at high speed to improve the output waveform. In addition, a diode D4 is connected to the + side input of the comparator 262.
Threshold 1 hold variable voltage 8 through 0° resistor R57
50 is applied. This threshold variable voltage S
50 is the output of the analog switch 240 or the analog switch 241 (output of the optical output setting means) (see FIG. 17). FIG. 22 shows the relationship between the one-side terminal input waveform of the comparator 262, that is, the output waveform of the beam detector 346, the positive terminal voltage of the comparator 262, and the relationship between the output waveform of the comparator 262 at that time. When the laser beam passes over the beam detector 346 at high speed, a pulse current flows from the beam detector (PIN diode) to one input terminal of the comparator 262, as shown in FIG.
The waveform b is input. Assuming that the voltage at the + side input terminal of the comparator 262 is always a low voltage VO6 because the threshold variable voltage 850 is not applied, the output waveform of the comparator 262 is waveform a as shown in the dotted line. If the waveform is S, the output waveform will be as shown by the solid line. Here, waveform a is the photoreceptor 3
When the sensitivity of 01 is low and the laser output during the main exposure is 5i+w or more, the waveform is conversely when the sensitivity of the photoreceptor is high and the laser output is 5 mw or less. As can be seen from this output waveform, when the positive voltage of the comparator 262 is kept constant, the output waveform changes significantly depending on the amount of light incident on the beam detector 346. Therefore, the threshold variable voltage 850 is used to set the voltage of VO5 when the light intensity of the laser beam is large, and the voltage of VO5 when the light intensity of the laser beam is small.
By correcting the voltage to the voltage of O6, the second
As shown in Figure 2, the output waveform can be kept almost constant.

FIG. 23 (A>, <8) is a configuration diagram of the beam detector (PIN diode) 346. Figure 23 (A>, (
B) &N7410G; L light receiving element, 411 electrode wire, 412 mask plate, 413 laser scanning beam, 4
Reference numeral 14 indicates a light receiving element mounting base, and reference numeral 415 indicates an output lead wire. The PIN diode used in this example has a light receiving element shape of 2.5 x 2.5 mm and a response time of 4 n5.
It is from ec.

The laser beam 413 is scanned at a constant speed in the direction of the arrow in FIG. 23(A) by the rotation of the polygon mirror 313. When the laser beam 413 passes over the light receiving element 410, an output current flows according to the optical output of the laser beam 413. At this time, the input waveform of the one side input terminal of the comparator 262 in FIG. 21 becomes the waveform shown in FIG. 24. In FIG. 24, input waveform 1 is a waveform when there is no mask on the light receiving element 410, and noise is generated before and after the output waveform. This is mainly intended for cases where the light receiving element 410 itself is used for detecting light that is originally stationary or for detecting light that has a very slow speed even when it is being scanned, and the parallelism of the end surface of the light receiving element 410 is If the laser beam passes through the end face of a bad element, the output current becomes unstable. Therefore, in order to solve these problems, a mask 412 that does not allow the laser beam 413 to pass is attached on the light receiving surface of the light receiving element 410 to prevent the output waveform from breaking when the beam passes on the end surface. The mask 412
As shown in FIGS. 23(A) and 23(B), the light receiving element 410
The laser beam 413 has a structure in which a square window is opened in the end face part and the part not including the electrode wire 411 lead-out part.
The light is made to hit the light receiving element 410 only when it passes through the four corner windows. With such a structure, the accuracy, particularly the parallelism, of the window portion of the mask is increased, so that the input waveform to the comparator 262 can be a waveform that does not contain noise, as shown in input waveform 2 in FIG. 24.

FIG. 25 is a detailed circuit diagram of the print data write control circuit 119 in FIG. 13. The main functions of this print data write control circuit 119 are as follows:
The parallel print data 857 is serially converted to be written in a predetermined area on the photoreceptor 301 according to the size of the paper to be printed, and is sent to the laser modulation circuit 120. In addition, the print data S
A shadow signal for improving print quality is generated from the data contents of 57 and sent to the laser modulation circuit 120 together with the print data. Further, the laser modulation circuit 120 sends out signals necessary for setting the optical output. Further, a timing signal for controlling the output from the print data control section 2 is sent to the interface circuit 122. The other is to generate test I to print patterns necessary for maintenance.

In FIG. 25, 186 is an input/output port for transmitting and receiving signals necessary for control within the laser modulation circuit 120 and print data writing control circuit 119;
A counter/timer 188 controls the writing position of print data, test pattern generation, laser light output sampling, and the like. 189 is a crystal oscillator that serves as the reference clock for the image clock pulse and has an oscillation frequency of approximately 32M.
It is H2. 190 is a circuit for generating an image clock, which generates a pulse (approximately 8 MHz) corresponding to one dot, which is the minimum modulation unit of a laser beam. 191 is a control counter for serially converting print data in bytes (8 bits) received from the interface circuit; 192 is a circuit that generates a test pattern used during maintenance; 2
11 is test pattern data and interface circuit 1
a multiplexer for selecting print data from 22;
210 is a shift register that converts the 8-bit parallel data from the multiplexer 211 into serial data; 21
3,214 is a line memory for temporarily storing print data, and the memory capacity is 4096 bits; 212 is an address counter for the line memories 213 and 214; 215;
is a decoder for generating a signal for controlling the test pattern generation circuit. Numerals 226, 227, and 228 are knobs 70 for synchronizing print data and shadow data transmission timing.

Here, the details of the counters 187 and 188 will be explained. , 275 is a counter that determines the timing for correcting the amount of laser light for each line (horizontal scanning line), counts based on the reference clock signal 853, and generates a sample signal 875 used for correcting the amount of light and starting the line. 276 is a counter for determining the horizontal recording start position, which is counted based on the Q7 output (video first dot unit signal) S83 from the control counter 191 and outputs a horizontal recording start position (left margin) signal 884. . A counter 277 determines the recording end position in the horizontal direction, and counts based on the eighth dot unit signal 883, and outputs a write margin signal 885 indicating the data writing end position. Reference numeral 278 is a counter for positioning the start of recording in the vertical direction, and the count is performed based on the output of the gate 198 which uses the paper leading edge position (page top) signal 874 outputted from the input/output port 186 and the Q output of the flip-flop 204. The page top count output 876 is generated.

Numeral 279 is a vertical recording end positioning counter which counts based on the output of gate 198 as described above and outputs a page end count signal S77. 280
is a vertical test pattern control counter that counts based on the Q output of the flip 70 knob 240 and outputs a test pattern control signal 879.

FIG. 26 shows the interface circuit 12 in FIG.
2 is a detailed circuit diagram of No. 2. In FIG. 26, 263 is an input/output port that receives command data and print start command signals from the data control unit 2, and sends status data and ready status signals of the print control unit to the data control unit 2; 264 is an 8-bit latch for both command and print data.

265 is a transceiver/receiver for the Inter 7Ace data bus 859. Reference numeral 266 indicates a decoder for the data selection signal 860 that specifies data on the data bus 859, and reference numeral 269 indicates a control circuit for the BUSY signal that controls the data sending timing to the data control unit 2 when command data and print data are received.

Next, details of the interface signal will be explained. In FIG. 26, 859 is a bidirectional 8-bit data bus, and S60 is a data selection signal on the data bus 859.
Data on the data bus 859 is selected by a combination of two signals C0M and ID5TA. 861 is IPRDY
A signal indicating that the print control unit 100 is in a ready state.

S62 is IPREQ, a signal that allows the data control unit 2 to send the print start signal @I PRNT, and S63 is the IP
At END, the data control section 2 receives this signal and stops sending out the print data.

864 is IH3YN, a request signal to send one line of print data, S65 is IPRNT, a print start command signal, 83
0 is a strobe signal for commands and print data, abbreviated as l.
5TB, 866 is IBSY and the strobe signal S30
This is a signal that permits transmission of the status data and permission for the data control unit 2 to read the status data.

Commands and print data are sent to transceiver/receiver 26
The status identification signal 868 is output to the output line 872 of 5.
It is output when it is FF. Data on output line 872 is transferred to data latch 264 by strobe signal 830.
latched to. In the case of command data, the data is latched to the input/output port 263, and after the command is identified, the specified operation of the command is executed. In the case of print data, it is sent from an output line 859 to the print data write control circuit. Also, the status data is sent as follows. By receiving a status request command on the print control unit 100 side, the status contents corresponding to the command are set in the status data output 871 of the input/output port 263. The set status data S71 is input to the transceiver/receiver 265. The input data is output onto the data bus 859 when the status identification signal 868 is ON.

Details of the commands and statuses used in the print control section 100 are shown in FIG. 27.2.8.

In FIG. 27, SR1-SR6 are status request commands corresponding to status list 6 in FIG.

PSON is a power save command that reduces the power consumption of the fixing device 331, and PSOF is a command to cancel the power save state.When not recording, the power save command PSON reduces the power consumption of the fixing device 331 to save power, and when recording Sometimes power save cancellation command P
By SOF, '7-eA regular omtrm addition 8111
0 fixation can be achieved. C3TU is a cassette upper stage paper feed designation command, C3TL is also a lower stage designation command, VSYNC is a command to instruct the start of sending print data from the data control unit 2, MF1 to 9 are manual feed mode designation commands, and 78M1 to 4 are paper feed designation commands. Top/bottom margin specification command that specifies the printing start position of SOF
indicate commands for forcibly turning off shadow exposure.

In Fig. 28, during paper conveyance, the status indicates that paper is being fed and the paper is being conveyed into the printer, and the select switch ON is the select switch 354 of the operation unit.
The VSYNC request status indicates that the print control unit 100 has received a command to start printing and is now ready to receive print data, and the manual feed status indicates that the paper feed mode is manual feed mode. The status to notify, upper/lower cassette is the status indicating the status of the selected cassette in the cassette feeding mode, and top/bottom margin is the status of the top/bottom margin selected by the top/bottom margin commands (78M1 to 78M4). status, cassette size (
Upper row) and cassette size (lower row) are the statuses that indicate the size code of the installed cassette, Test/Maintenance is the status that indicates the test/maintenance state, Data resend request is when reprinting is required due to jam etc. During wait, the status indicates that the printer is in a warm-up state of the fixing unit. During power save, the status indicates that the printer is in power save mode by the power save command (PSON). Operator call indicates that an operator call factor of status 4 has occurred. Serviceman call indicates that a serviceman call factor of status 5 has occurred. Tray full indicates that there are more than a specified number of sheets in the paper output tray and the tray is full. Toner bag replacement indicates that the toner pack is full of toner. Paper jam indicates that paper has jammed inside the machine. No Toner indicates that there is no more toner in the toner hopper. Cover open indicates that the front door is not closed. A timing error indicates that there was a problem in transferring print data. Fuser failures include fuser heater burnout, temperature FLJS, E burnout, etc.
Indicates that there is a problem with the fuser. A laser failure indicates that the laser diode does not reach its specified output or that the beam detector is unable to detect the beam. Scan motor failure indicates that the scan motor does not reach the specified rotation speed even after a certain period of time has elapsed since startup, or that the scan motor deviates from the specified rotation speed for some reason after reaching the specified rotation speed.

Heat roller replacement indicates that the fixing roller counter shown in FIG. 15 has reached a specified value and that the fixing roller needs to be replaced. Drum replacement similarly indicates when the drum replacement counter reaches a specified value and the drum needs to be replaced, and developer replacement similarly indicates when the developer replacement counter reaches a specified value and the developer needs to be replaced. .

FIG. 29 shows the positional relationship between one scanning range of the laser beam including the beam scanning section 349 on the photoreceptor 301 in FIG. 3, and the beam detection position and data writing position that fall within the scanning range. FIG. In FIG. 29, 416 is the beam scanning start point, 417 is the beam scanning end point, and the beam that has reached the beam scanning end point 417 is moved to the next surface from the beam scanning starting point 416 at time O by the next surface of the polygon mirror 313. Begin beam scanning. 418 indicates the beam detection starting point of the beam detector 346, 428 indicates the left end surface of the photosensitive drum, and 429 similarly indicates the right end surface. 419 represents the left end surface of a sheet of paper size 80, and 420 similarly represents the right end surface. 421 represents the left end surface of a sheet of paper size A3, and 420 similarly represents the right end surface. 421 is the same A
The data writing start point 422 also indicates the data writing end point for the three sizes of paper.

423 is the left end surface of paper size 86, 424 is the right end surface, 425 is the data writing start point of the same size, 426
Similarly, each represents the end point of data writing. Also 42
7 represents the center point of the paper.

d4 is the distance from the beam scan 418 to the A3 size writing start point, d5 is the same < distance to the A6 size writing start point, d6 is the same < distance to the A6 size writing end point 426, d7 is A3 size Each represents the distance to the writing end point. d8 represents the distance from the beam detection point 418 to the right end surface 420 of A3 size paper. Further, d3 represents the range of one scan of the beam. d14. d9. dlo indicates the effective printing range in A3 and 80, respectively. As is clear from this drawing, the paper feed of this printer is always centered around the paper center point 427, so the starting point for printing from the beam detector position 418 differs depending on the paper size. It is necessary to write data after a lapse of time corresponding to the distance from when the detector 346 detects the beam to each writing start point. Instead of performing such control, this printer does not use a paper edge feed mechanism, so it is possible to print on the entire surface of the paper. In this embodiment, the left and right margins on the left and right sides of the paper are set to 3 mm, but it is possible to set them to O. Furthermore, conventional printers that perform edge-feed conveyance usually require a margin of about 8 to 10+U, which has the disadvantage that a considerable portion of the paper is not printed.

FIG. 30 shows the paper size and print area portion of FIG. 29 not only in the horizontal direction but also over the entire surface of the paper. In FIG. 30, 436 represents A6 paper and 437 represents A3 paper. 419,420°421.422,423,4
As for 24,425,426.427, the same positions as in FIG. 29 are shown. 430 represents the leading edge of the paper, 432 represents the data writing start point in the vertical direction of the paper, 431 represents the trailing edge of the A3 size paper, and 433 represents the end point of A3 size data writing. 434 represents the trailing edge of the paper for size 6, and 435 represents the end point of data writing for size ○.

Next, the operation of the component device will be explained with reference to the time charts of FIGS. 31 and 32.

Ready signal IPRDYO (361) of print control unit 100
becomes ready for printing.

At the same time, the print start signal IPREQO (862) becomes active. Next, the laser enable signal LDON1 (
849) rises to 1. This signal S49 causes the 17th
The transistor 258 shown in the figure is turned on. At this time, the second
The data flip 70 tabs 226 to 228 in FIG. 5 are not set, so the print data signal 847 and shadow signal 848 are both 0'. Since the laser enable 849 is '1', the print data is O', and the shadow signal 848 is 0', the gate 246 in FIG. do. Then, the monitor photodiode 260 operates, the operational amplifier 239 operates via the operational amplifier 232, and a laser ready signal LRDYI (843) is generated. Next, in synchronization with the horizontal periodic signal 1-1sYO (854), the counter 2
A sample signal sMPTo (s75) is generated from 75. This signal 875 is the distance d3 (distance of one line) between 416 and 417 in FIG. 29 that defines the paper size.
It is used to set the time corresponding to . This allows the light amount to be corrected for each line and is used as a line start signal. That is, this signal 875 opens the gate 193 in FIG. 25, the gate 194 generates a sample signal 845, and this sample signal S45
is connected to the analog switch 2 via the gate 244 in FIG.
36 is turned on, a correction signal is given to the laser diode 259, and thus light amount correction is performed for each line. PTCTO (876) is the output signal of a counter (page top counter) that determines the leading edge of the paper, and PE0 page 0 (877) is an output signal of the counter (page end counter) that determines the end position of the paper. When it is time to write the image, VSYN
Send the status of the C request to the external device. Due to the stiffness, a VSYNC command is issued, and when it is received, the PTO
P (873) is output and the number of 1-ISYNC lines begins to be counted from that point. Similarly, specify how many lines to write from that position (end position W). In order to be able to change this designated value, a top margin nT and a holatum margin nE are provided. When the above specification is made, PTQP is executed before the leading edge of the paper when VSYNC comes.
A signal is output. For example, if a margin of 5Ill is required, the number of lines including that margin is counted.

If the top margin is 10 nua, data corresponding to that amount will be set in the timer.

The position of the bottom can be determined in the same way. Once the data is set in the timer, the gate is opened and the count is started, and when the count is finished, it starts up. Gate 201 in FIG. 25 determines where to write in this way. LSTO (878) is the synchronization output of flip 70 tube 204 and is set by -1sYNc and reset when the sample timer signal rises. This reset line is connected to LDON in Figure 25.
The reset line is included in the signal (849) and normally does not work, but is forced to be reset. The reset generates the Q output of the flip 70 tube 204, and the clock generation circuit 190 operates to count the clocks from the oscillator 189.

This clock generation circuit 190 divides the frequency of the clock from the oscillator 189 by four, and outputs a bit-by-bit signal as a line start signal only while sT is set. This output becomes two types of signals S82 and 887 with different phases. As a result, synchronization for -lines is achieved. V
DATI is a print data signal (S47), which is output as serial data by the operation of the P/S conversion shift register 210. That is, the P/S conversion shift register 210
is operated by the signal S82 from the clock generation circuit 190, but when the load signal is not applied, the output 886 is O' (no laser writing), and when the load signal 888 is input, the output 886 is O'. Convert and output serially.

At this time, gates 207 to 209 provide 1 to 8 bits.
It will be loaded every cycle. Here, the generation timing of the load signal will be explained.

When there is a place where you actually want to write, data must be set every time the paper size changes, but the counter that controls this is the left margin counter 276 (Fig. 25).
Data are shown in Figure 29 d 9. dlo) and write margin counter 277 (data is 611.d12 in Figure 29).
). In this case, the set defines the distance between the left and right sides based on the center of the paper. H8YN
When the LST signal (878) is output in synchronization with the C signal, the flip-flop 196 is set, which causes the gate 19 to
8 sparkles and the counter 276 starts counting. In this case, the video clock is counted not every pit, but once every 8 bits. When the count output that comes out every 8 bits is set in accordance with the left margin Nl-... and the right margin NRm, tC counting is performed in synchronization with the LST signal (S78). Then, it starts up after setting and outputting the count number. Therefore, the gate 201 determines the vertical direction, and the gate 199 determines the horizontal direction, so that writing is performed at the point when the outputs of both gates become (1, 1). At this timing, the load signal is output, and the data S86 is serially converted from the shift register 210 and sent out.

Line memory out signal LMOT (880) is the output of OR gate 222. This controls which data from the line memories 213 and 214 is to be sent. That is, this sending timing is
Controlled by 03. That is, the output state of the flip 70 knob 203 changes every time a clock pulse is applied, and the gates 220 and 221 are opened alternately, so that the output DOLJT of the line memory 213 or 214 is alternately read out. . line memory 21
3. Timing of writing to 214 is also gate 217.2
18 are opened alternately and controlled. This is done in order to facilitate processing by allowing data to be written and read at the same time when a shadow method, which will be described later, is employed.

Next, LDAONl (381) will be explained with reference to FIG. 43.

In this type of recording device, if the laser is not emitted over the entire axial direction of the photoreceptor 301, it can only be emitted, for example, on small size paper (B5, A4, etc., such as paper 458 shown in FIG. 43). In many cases, printing is not performed, and as a result, toner and the like do not adhere to the area near both ends that are not used. Further, even for a large size paper (for example, paper 461 in FIG. 43), there is an unused area (the used area for small size paper 458 is also within the shaded area 459). If such an area is provided where toner does not adhere for a long period of time, there is a problem that when the blade scrapes off the adhered toner after recording, the contact resistance of the blade in the unadhered area becomes large and the surface of the photoreceptor is scratched. be. So with this device. As shown in the time chart of FIG. 31, the line data on signal LDAON1 (S81) is generated immediately after printing for one sheet of paper is completed, and the print data signal VDAT1 (S81) is generated within this generation period.
847), and by this operation, lines (images) 460 and 463 spanning the entire axial direction of the photoreceptor as shown in FIG. 43 are written after printing for one sheet of paper is completed. The above drawbacks have been eliminated. In this case, the timing of writing line data is the data LDATn− one before the final stage data LDATn in the data of the line memory out signal LMOTI (880).
The signal is generated when a predetermined time tx has elapsed from the falling edge of signal 1. Note that such lines are not necessarily written periodically after each sheet of paper has been printed, but can be set to be written every lot (for example, every 10 sheets or every 100 sheets). You may.

Next, with reference to Figures 33 to 36, we will discuss in detail the method used to make characters easier to see by adding shadows to printed characters (also called the shadow method). .

Determination as to whether or not to generate the shadow signal 348 is made by various gates 220 to 225 which alternately input data from the line memories 213 and 214, and three flip-flops 2.
26 to 228 and the gate 231 on the output side thereof. Among them, the flip 70 knob 227 is in the horizontal direction (
The flip-flop 228 contributes to determining a shadow based on a change in level in the vertical direction (line direction), and to determining a shadow based on a change in level in the vertical direction (vertical direction). That is, the serial data that is about to be written is read from the line memory 213 and is sent to the 7th lip buffer.
When the knob 226 is set, the data in the previous line direction is stored in the flip-flop 227, so for example, when the current data is rOl and the previous data is 1', the shadow signal 848 is output. . Similarly, the data of the previous line and the data of the current line are sent to the gate 223.
For example, when the data on the current line is 0' and the data at the same horizontal position on the previous line is 1', the flip 70 is set and a shadow signal is generated. still,
A shadow signal is also generated when both control flops 227 and 228 are set. This state is shown in FIG. 32 with shadow out signal 5OUTI (886), print data signal VDATI (847), and shadow signal 5DAT1 (
848).

FIG. 33 shows a conventional development pattern when the shadow method is not used, and FIG. 34 shows a development pattern when the shadow method is used. In this way, when the characters "謹" are printed, shadows are added to FIG. 32, making it very easy to read.

FIG. 36 is a characteristic diagram P that intersects a vertical line S1 with a horizontal line S2 and shows the relationship between exposure position and exposure energy in the upper right area of the figure.
AT1. PAT2 is shown in a characteristic diagram Q showing the relationship between the surface potential of the photoreceptor and exposure energy in the upper left area of the figure, and characteristic diagrams R1 and R2 showing the relationship between the exposure position and the surface potential in the lower left area of the figure.
are shown respectively. In this figure, among the characters in Figures 33 and 34, "8" in the X direction and 11 in the Y direction.
4 to 21''. As shown in the figure, the characteristics PAT1 and R1 of the pattern shown in FIG.
The characteristics PAT2 and R2 of the patterns shown in the figure are different. In particular, regarding the development characteristics, at a certain development level, the width D1 of R1 in FIG.
It can be seen that the width D2 of R2 in Figure 4 is larger. In addition, FIG. 35 is a characteristic diagram showing the relationship between the exposure position and the exposure energy, and the energy of P(ON) during laser irradiation is, for example, 6+++w, and the energy of P(S
The energy of H) is, for example, 4n+w.

The above shadow method can be summarized as follows.

In a device that records recording information (character information, etc.) on a recording photoreceptor by beam scanning in accordance with differences in beam intensity, serial binary input data is transferred to beams having first and second intensities (the P (ON) and P (OFF)), and when the input data has a specific relationship, the first or second intensity intermediate beam is replaced with the first or second intensity beam. The third intensity located at (
halftone) beam is used to record.
Determination of this specific relationship is possible when, for example, beam scanning is performed sequentially for each horizontal line. (b) determining that the recorded data changes to data that does not contribute to character formation, and scanning the unintentionally recorded data portion immediately after the change with a beam of a third intensity; and (b) scanning the current line in the horizontal line. The data is compared with the data of the previous line in the vertical direction corresponding to that position, and as in (a) above, when significant recorded data changes to unintentionally recorded data, the unintentionally recorded part immediately after the change is scanning with a beam of intensity.

Note that when adding the shadow, it may be applied regardless of the type of recorded information (for example, text information and image information), but
It is preferable to use this method only when dealing with textual information. In this case, as shown in the flowchart in Figure 55 (A), the microprocessor determines whether or not the flow is a "shadow" flow. For example, image information), "Shadow J is disabled and automatically executed.The command in this case is rsONFShadow0N10FF shown in Figure 27.
It is J. Or on the panel [Shadow 0N10F
An F+ switch may be provided so that the operator can select it arbitrarily.

By using the shadow method as described above, the recorded information is character information (in some cases, it is possible to add a "shadow", so the printing quality can be improved.Especially when recording with a high-density beam, conventional binary information can be It is possible to prevent lines from becoming blurred due to a decrease in printing density of one-dot lines, which was a drawback of the recording method based on beam intensity.As a result, the printing 11 degrees of one-dot lines is increased, making it suitable for high-dot kanji fonts such as 40x40 dot configurations. In addition, it is possible to increase the printing quality of polygon mirrors.Also, it is possible to widen the permissible range of vertical deflection of the beam on the photoreceptor due to "plane deflection" of the polygon mirror, making it easier to process polygon mirrors. , it also has the advantage of being inexpensive.

In addition to character information, the shadow may also be applied to simple graphic information.

Next, regarding charge correction, FIGS. 37 to 41 and 56
This will be explained with reference to the flowchart shown in the figure.

FIG. 37 shows an example of a configuration in the charging high voltage power supply circuit 160, which is a configuration example of the high voltage power supply 0N10FF signal 8.
35, a voltage control circuit 445 whose operation is controlled by the voltage control circuit 445, a step-up transformer 446 which applies a frequency output to the primary side and generates a high-voltage output from the secondary side, and a step-up transformer 446 which rectifies the output of the step-up transformer 446. a high-voltage rectifier circuit 447 that applies a rectified output to the charger 304; a current/voltage conversion circuit 450 that inputs the current flowing to the charger 304 and converts it into a voltage;
The operational amplifier 449 has one input as the output of the current/voltage conversion circuit 450 and the other input as the output of the control reference voltage generation circuit 448. The control reference voltage generation circuit 448 is controlled by an analog control signal 836 to output different control reference voltages. According to such a configuration, the output frequency of the voltage control circuit 445 is determined based on the output from the control reference voltage generation circuit 448, and a high voltage output is generated based on this, and the current of the charging charger at this time is determined. The output voltage is applied to the current/voltage conversion circuit 450, and the output voltage is compared with the reference voltage by the operational amplifier 449, and a control operation is performed so that the two match, so that the output applied voltage can be stabilized.

Here, the contents of the analog control signal 336 will be explained in detail.

As shown in FIG. 38, the photoreceptor 301 has a characteristic that its surface potential changes significantly with temperature changes.

In the figure, the horizontal axis represents temperature, and the vertical axis represents surface potential change △vO
This shows the type of drum: 451°452.45
Each type has different characteristics. Also, the 39th
The figure shows each drum 451, 452, 45 at a temperature of 25°C.
3 shows a characteristic diagram showing the relationship between the drum inflow current ID and the surface potential vO of No. 3, which is a proportional straight line. Therefore, in order to keep the surface potential constant, it is sufficient to change the drum inflow current 10. For example, in order to maintain a surface potential of 800V for the drum with characteristic 451 in FIG. Inflow current change m△ID′ corresponding to 0
(Various characteristic data of the photoreceptor is stored in the RAM 107). Here, since the inflow current ID and the output current have a corresponding relationship as shown in FIG.
By changing 6 to 2V, 4V, and 6V, the inflow current ID can be adjusted. Figure 41 shows
Analog input current (D/A converter 165 in Figure 15)
For example, if the temperature of the drum 301 is detected by the temperature sensor 342 (thermistor in FIG. 14) and the analog control signal S36 is applied in response to the temperature change. good.

The charging correction is performed based on the above contents, and its operation will be explained based on FIG. 56. 14th
When the thermistor 342 shown in the figure detects the temperature of the drum, the A/D converter 271 converts it to digital compensation, and when the data conversion is completed, the temperature data DTn and the temperature 25
A value 06 is read by subtracting the drum thirst data DT25 at ℃. Next, the reference data DV2 at a temperature of 25℃
5 is read, DV25+DΔV is calculated, and the calculation result DVn is output to the D/A converter 165. Then, referring to the RAM 107, the drum characteristic data at address r6000J shown in FIG.
, and further read the feedback error data DΔV8. Next, read the reference data DV25 at a temperature of 25°C,
It calculates DV25+DΔV and outputs the calculation result DVn to the D/A converter 165. Then, apply Vn to the analog input of the charging high voltage power supply 160 (836)
In addition, the control input signal 335 of the charging high voltage voltage #il 60
Turn on and perform correction. The above correction is repeated every time the temperature changes to keep the surface potential of the drum constant.

Note that the characteristics of the various photoreceptors (drums) stored in the nonvolatile RAM 107 can be specified by the operator from the outside. That is, as shown in the flowchart ① in FIG. 60, when it is determined whether or not to replace the drum,
If the drum is to be replaced, the drum characteristic number is set and the test key is turned on, after which the drum characteristic number is written in the drum characteristic number area of the non-volatile RAM 107. Therefore, thereafter, the characteristics of the drum currently in use are always selected, and corrections are made based on this.

When the charge correction described above is performed, the charge potential of the photoconductor is kept constant even if the temperature of the photoconductor changes due to changes in the external environment or temperature rise in the gas, so the charge potential based on temperature changes can be adjusted. It is possible to prevent defects such as fogging due to a decrease in print density, a decrease in print density, or an increase in charging potential, and it is possible to always provide clear prints. Further, in this embodiment, by inputting (external setting) information classifying the temperature characteristics of the photoreceptor, correction is performed accordingly, so that temperature correction of charging characteristics can be performed with extremely high accuracy. Therefore, variations in the temperature characteristics of the photoreceptor itself can be alleviated, and there is an advantage that the range of specifications for the photoreceptor can be expanded.

Next, the flowcharts shown in FIGS. 47 to 56 and the flowcharts shown in FIGS.
The operation of the entire apparatus will be explained with reference to the time charts shown in FIGS.

After the power is turned on, the door switch 129 is turned off.

Make sure that the paper ejection switch 336 is OFF, the manual stop switch 328 is OFF, the pass sensor 123 is OFF, the temperature fuse 130 is not disconnected, and the paper ejection tray 3 is turned off.
84 is confirmed to be full (FULL), and it is further confirmed whether the mode is test print mode, maintenance mode, or replacement mode. If there is no problem, the MC relay 131 will turn on, and the fuser heater lamp 333 will turn on.
ON, the scan motor 312 is driven to rotate at a low speed and timer A (TIMA) is started. Timer ATIMA
When TIMA counts a predetermined time t1, mechanical parts such as the drum motor and developer motor are turned on, and then when TIMA counts a predetermined time t2, the laser 344 is turned on. When time t25 is counted by TIMA, it is determined whether the laser is ready or not, and if yes (Y), then TIMA=t26 is counted and the transfer charger, laser, developer motor, and developer sleeve bias are each turned off. , and the drum motor and heat roller motor when the time surface is light at TIMA=t27.

The static elimination lamp and the pre-transfer static elimination lamp are turned off.

Next, at the timing of TIMA=t29, it is determined whether the scan motor is ready or H8YNC ready, and the answer is yes (Y).
If so, TIMA is stopped (see FIG. 47).

Next, a determination is made as to whether it is a “treyful in status 4”,
It is determined whether the "toner pack is replaced" or not, and whether there is "no toner" or not. If the paper is "tray full", the "tray full" flag is set to "0'" after paper is removed from the output tray, and the paper is ejected. Reset the tray counter and "Replace toner pack"
If so, a reset will be performed when the state returns to its original state, and in the case of toner replenishment, a reset will be performed when the state returns to normal.If the flow passes 0 or more, then "Status 3"
It is determined whether or not the mode is “power saving”, and the
), then it is determined whether "Paper out" in "Status 4" is detected, and if it is YES (Y), it is determined whether "cassette paper out detection is ON or not; if NO (N)", it is determined " The "out of paper" flag is set to "0", and if the "fixer is ready", the "status waiting" flag is set to "0". Next, IPRD
YON and IPREQON are determined, and it is determined whether "power saving" is in progress or "out of paper", and if there is no problem, ITMA starts. The registration motor 149 rotates in reverse at TIMA=t01, and stops at TIMA=t02. At this stage, the leading edge of the paper is held between the paper feed rollers.

Next, it is determined whether it is manual feed J or not, and if no (N>, it is determined whether it is rlPRNT ONJ or not, and yes (Y)
If so, NPREQ becomes 0FFJ, and the scan motor 312 is driven to rotate at high speed by setting the output of the speed control signal 840 to HIGI-level, and the timer F
Stop (TIMF). Next, timer E (TIM
E) is in operation or not, and if it is in operation, rTI
ME=t 30 is determined, and if yes (Y), TI
ME stop and transfer shaja 305. Peeling charger 306. The developing device motor 141 and the fixing device motor 143 are each turned on.

If rTIME is not 1.30J, TIME is stopped and the flow shifts to [F] (see FIG. 48).

Next, TIMA starts and plaid solenoid 158
turns on, rTIMA=t IJ, developer motor 1
41. Static elimination lamp 302. Pre-transfer static elimination lamp 303. Each of the drum motors 147 is turned on. rTIMA=
At t2J, the transfer charger 305. Fuser motor 143
becomes ON.

When rTIMA=t 3J, the peel charger 306 is turned on.
Then, when rTIMA=t4J, it is determined whether the scan motor 312 is at a constant speed, and if rYEsJ, T'1MA is restarted from O'. rN
If it is OJ, the above operation is performed after waiting for the scan motor 312 to reach a constant speed. Next, it is determined whether the cassette is in the "manual feed" mode, the upper or lower cassette, and if it is the upper cassette, the paper feed motor 151
rotates forward to feed the upper stage, and if it is the lower stage, ITEMA
=t After waiting until 5J, the paper feed motor 151 is reversed and lower paper is fed. Next, the laser 344 is turned on when rTIMA=t5J, and the charger 304 is turned on when rTIMA=t6. rTIMA=t
Check whether it is laser ready with 7J and select YES (Y).
), the "vSYNC request" flag in "Status 1" is set to 1'. Then timer B<TIMB
) and move to the flow of ◎ (this is the 49th step)
figure).

Next, the paper feed motor 151 is stopped at rTIMA=31J,
Determine if rVSYNC command received 1 and select YES (Y)
If so, it is determined whether or not rTIMB<t32J, and if yes (Y'), TIMB is stopped, the count of 1 page top "[page end counter"] is started, and image writing processing is performed. Timer 〇、D (TIMC
, D) and T at IT IMA=t 34J.
The IMA step 1 stops the paper feed motor 151. Next, register motor 149 at r'TIMc/D=t 35j
Forward rotation, total counter 354 ON, 1-TlMC
/D=t36" to determine whether the toner concentration is high or low. If the density is low, the toner supply motor 159 is turned on.

``Next page end interrupt'' is determined, and if YES (Y), an image writing end I PEND pulse is output.

The junction counter is set to +1, and "tray full", "drum replacement", and "developer replacement" are performed.

If "Heat Roller Replacement" is selected, each status will be displayed. Incidentally, if the determination result of ``receiving the I'VSYNC command'' is NO (N), then rTIMB=t46'' and the charger 304. C) FF, rTIMB=t47J and laser 344. Hack charger 304 OFF, rTIM
B=t 47J and laser 344. Hakukuchaja 3
06. Reset the developer motor 141 hOF, rTI
MB=t 48J and transfer charger 305. Turn off the fuser motors 143 and turn off the drum motors 147.rTIMB=t49J. Static elimination lamp 302. Learn to remove static electricity before transfer? nnG-P)lFtl, nFF-rT rM
B=j 50'', the plaid solenoid 158 is turned OFF.

Also, in the flow of rTIMB<t 32J, -(N)
If so, then it is determined that rTIMB<t 33J, and no (
N), TTMB stop and TIMA start. After that, turn on the plaid solenoid 158 and rT
At the stage of IMΔ-11J, the developer motor 141. Drum motor 147. Static elimination lamp 302. Pre-transfer defrosting lamp 30
3 are each turned ON. and rT+MA=t2J
When the transfer charger 305. Turn the fuser motor 143 to O.
When rTIMA=t3J, peel charge t3
Turn on 06. Next, it is determined whether rTIMΔ-t4,1 or not, and timer A is stopped by -H and restarted. The developer motor 141. Transfer charger 305. Hakuli Charger 306. Each of the fixing device motors 143 is turned on. When I'TIMA=t5J, the laser 344 is turned on, when rTIM=t6J, the charger 304 is turned on, and when rTIMA=t7J, it is determined whether or not the laser is ready, and if YES (Y), TIMA is stopped (see FIG. 50).

Next, it is determined whether the toner full detection switch 126J is ON or not, and if it is ON, a display is displayed. ”, and if it is not manual feeding, then it is determined that “specified cassette paper is out”, and if there is no paper, a message to that effect is displayed and the 5TPF (stop flag) is set to 1'. Next, timer E (TIM
E) and timer F (TIMF) are started. If the stop flag is 1', 5TPF is set to 0' and print ready IPRDY is turned OFF.

If 5TPF is not 1, it is determined whether it is "manual feed 1" or not, and if it is "manual feed 1", TIME stop, manual stop switch 328 OFF 1 manual feed "O"
, TIMB stop, cassette paper out detection switch ON
A determination is made as to whether or not the print request IP
REQ is turned ON, and the process moves to the flow shown in (2) in FIG. 48 (Fig. 51).

Next, the contents of the timer interrupt in each flow will be explained with reference to FIGS. 52 and 53.

This determines whether or not each of the timers A, B, C, D, and E is in operation, and when each timer is in operation, counts up. Read all hexagonal information in the port input reading part. Then, the timer is stopped when rTIMc10=t 38J, and it is determined whether FTIME=t 39J or not. From then on, the operation of timer E (TIME) is continued, and at each time, "toner replenishment motor 159J, r registration motor 149 ” to stop. Then rTIME
= t4, then determine whether rTIMA is in operation (
This is to determine whether the next sheet of paper will be printed). If TIMEA is in operation, TIME is stopped. When IrTIME=t41J, the charger 304 is turned off.

FTIME=t 42J and laser 344. Hakuli Charger 306. Each developer motor 141 is turned off. Transfer charger 305 with rTIME=t 43J
．． Turn off each fuser motor 143, rTIME
=t 44J, drum motor 147, static elimination lamp 302
．． The pre-transfer static elimination lamps 303 are each turned off (see FIG. 52).

rTIME=t 45J and plaid solenoid 158O
FF, TIME stop. Here, when the timer F measures 180 seconds from the start of time measurement, the output of the speed control signal line 840 is set to a LOW level, the C scan motor 312 is rotated at a constant speed, and the timer F is stopped.

After that, it is determined whether "the fuser temperature is normal" or not, "the fuser temperature is in the fuse stage", and "the scan motor 312 is ready".
, ``It is determined whether the door switch 129 is OFF or J, and various processes are performed depending on each state.

Next, the contents of the command interruption in each flow will be explained with reference to FIG. 54. When command interrupt processing starts, it is determined whether there is a "parity error" or not, and if it is an error, [Status DATA81J flag is set to 1].
This results in an [illegal command error]. If it is not a “parity error” [7-r-II/7T))-1#Q
Q 1 and AffillIPi are determined, and when they are within the range, an output corresponding to one of them is generated. If it does not correspond to any of the [Status Requests], it is determined whether the "Top/Bottom Margin j" is selected, and if so, the "Top/Bottom Margin" is specified and becomes 1' in the "Status Set", and rDATA21 to 11
” is specified. If it is not [l-tube/bottom margin], it is determined whether "manual feed specification" is specified or not.
If YES (Y), manual feed display and paper size display are performed next, and the paper size register is set. Then, with the manual feed status set, the status 1 roars rDAT△4
1'' flag becomes 1'', and then the flow shifts to status 4 where the paper out flag becomes 0''. If it is not "manual feed specification", it is determined whether "cassette specification" is selected, and if it is "cassette specification", the upper/lower display paper size is displayed, the paper size register is set, and the manual feed status relet is displayed. Status becomes 1 and DTA41
77g0', H\AI disconnected whether there is no cassette paper [7
>1, the flag becomes '1'. "Cassette specification"
If not, it is determined whether "select lamp 1 is lit" or not, and it is determined whether the online select lamp (external device, for example, the one specified by the host side) is lit. If YES (Y), the select lamp is lit. The lamp is turned on, and if the select 1 lamp is not turned on, it is determined whether the select lamp is turned off or not. If YES, the select lamp is turned off, and if NO (N), the process moves to the next flow.

Next, the flowcharts shown in FIGS. 55(A) to 55(C) will be explained.

In addition to the above-mentioned "shadow method", "power save" is included in FIG.

The fuser is controlled to the power save temperature and set to [Status 3 power save flag 1], and when power save is canceled, the scan motor 312 is turned on, the fuser is controlled to the normal temperature, and the [Status 3 power save flag is set to O].
”, and if it is “Start image data transfer”, it is shown in Figure 55 (B
), the process moves to the flow of (C).

The paper size register is read, the top margin table data (Dl) of the specified Mυ size is read,
It is determined whether the top/bottom margin designation is 5mm,
If NO (IN), the 1-tube/bottom margin change table data D2 is read. Next, the calculation of top margin table data D1+margin change table data D2 is performed, and the contents of the top margin adjustment switch (442 in FIG. 14) are read. Next, the top margin adjustment table data D3 corresponding to the switch is read, and the margin adjustment table data D3 is added to or subtracted from the value of Dl etc. (D1+D2), and the calculation result D4 is set in the page top counter 278.

And bottom margin table data D for the specified paper size
5 is read and the top/bottom margin specification is 51n1
11 or not, and if NO (N), the top/bottom margin change table data D2 is read, the bottom margin table data D5 and the margin change table data D2 are reduced, and the top margin The contents of the adjustment switch 442 are read, and the top margin adjustment table data D3 corresponding to the switch is read. Next, the margin adjustment table data D3 is added to or subtracted from the value of D5 or (D5-D2), and the calculation result D4 is set in the page counter 279. Next, the light margin table data D7 for the specified paper size is read, and a cassette/manual feed is determined. If the cassette is selected, it is determined whether it is the upper stage (reference) or not, and if it is not the upper stage, it is the lower stage.The content of the cassette upper/lower stage adjustment switch (44 in Fig. 14) is read, and the cassette upper/lower stage corresponding to the switch is read. Read adjustment table data D8. Add or subtract the above D8 to the value of the above D7, and the calculation result D9 or the above D7
is set in the write margin counter 277. If manual feed is specified, read the contents of the cassette/manual feed adjustment switch (440 in Figure 14), read the cassette/manual feed adjustment table data D10 corresponding to the switch, and then set the adjustment table data to the value of D7. D10 is added or subtracted, and the calculation result Dll is set in the write margin counter 277.

Next, left margin table data D1 for the specified paper size
2 is read, cassette/manual feed is determined,
If it is a cassette, it is determined whether it is the upper stage (reference) or not.
If it is not in the upper stage, it is determined that the cassette is in the lower stage, the contents of the cassette upper/lower stage adjustment switch 440 are read, and the cassette upper/lower stage adjustment table data D8 corresponding to the switch is read. The data D8 is added to or subtracted from the value of the D12, and the calculation result D13 or the data 012 is set in the left margin counter 276. In addition, in the case of manual feeding, the contents of the cassette/manual feeding adjustment switch 441 are read, the cassette/manual feeding adjustment table data 010 corresponding to the switch is read, and the data DIO and the data DI2 are read.
The calculation result D14 is set in the left margin counter 276.

The details of the cassette paper printing during the aforementioned flow are shown in the time chart of FIG. 57.

When the print start signal IPRNTφ (865) is output, the print start permission signal IPREQφ (S62) rises. After that, the developing device motor 141 etc. are turned on, and the time [4 to t]
8, the paper feed motor 151 operates to convey the paper in the cassette. At this time, the laser diode 344 is turned on at time t5, and data writing starts from time t7 (the diagonally shaded period from time t7 to t11 is the data writing period). At time t9, the registration motor 149 rotates and writes data to the photoreceptor. is transferred to paper. Data writing continues until time 11 when IPREQφ (S62) falls, and after time t111!111I, the registration motor 149 continues to rotate until 2 and then stops. The laser diode 344 then becomes t14'C-0FF.

FIGS. 58 and 59 are time charts for explaining the operation of printing on manual paper. In the following explanation, the differences from the above-mentioned case of printing on ceramic paper will be explained.

In FIGS. 58 and 59, the paper feed motor 151 is not used, and the registration motor 149 is rotated in reverse to drive the paper feed roller, and is used for paper conveyance, and the registration roller is driven by forward rotation. ing. In addition, both of them receive the print start command IPREQ after receiving the "manual feed command".
φ (862) is made to rise. FIG. 58 shows a case where paper is set in the manual feed guide before the "manual feed command" is generated, and when the manual feed switch 326 is turned on due to paper setting, the time tol
Afterwards, the registration motor 149 rotates slightly in reverse and stops with the leading edge of the paper added, and a "manual feed command" is issued.
At the time when PREQφ (S62) rises, the registration motor rotates in the reverse direction again to convey the paper to the transfer position and then stops. Therefore, it is possible to print on paper from the cassette before issuing the "manual feed command".

In the case shown in FIG. 59, the manual field switch 326 is turned on after the "manual feed command" is issued first, paper is set in the manual guide, and the manual field switch 326 is turned on. In this case, the registration motor 14 The two are continuously rotated in reverse to transport the paper to the transfer position.

In any case, the manual stop switch 328
The registration motor 149 is set to stop at time 121 after a predetermined period (time t 20 > lapse of a predetermined period of time) while the paper is turned off (time t 20 > time 121). "JAL\" will not occur even if the paper size is specified for cassette paper, so such consideration is not necessary. Therefore, even if the cassette paper runs out, the size of the information to be printed will be smaller than the size of the information to be printed. Printing can be performed by preparing a large-sized paper, and it is also possible to use paper of a size that does not meet the standard, increasing the utilization of the device.

The flow transitions from the flow shown in FIG. 47.

The contents of O20 will be explained with reference to FIG. 60.

When the test print mode is selected, the flow shifts to (2), and the print specified by the print mode No. is executed via the DEST key. When the maintenance mode is selected, the flow moves to ■, and the maintenance mode operation of No. specified via the test key is executed.
When the replacement mode is selected, the flow moves to O, and it is determined whether to replace the drum, whether to replace the developer, or whether to replace the heat roller, and to select the drum characteristic number set and whether to replace the heat roller, respectively.
``Developer Replacement No. Set'', ``Heat Roller N.''

SET” allows you to set the non-volatile generation RAM10 through the test key.
Predetermined data processing for 7 is performed.

FIG. 61 to FIG. 63 are correspondence diagrams showing correspondence between display numbers and respective contents.

(The following is a blank space) Note that the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the present invention. The recording medium is not limited to a photoreceptor, but may also be a photosensitive paper.

``Effects of the Invention'' As detailed above, according to the present invention, the driving means of the scanning mechanism is rotated at a low speed when the beam is not scanning, so the life of the driving means and rotational support member is greatly extended. It can be extended, and it can also save energy. In addition, the judgment as to whether to start this low-speed rotation is made based on whether information from an external device is input within a certain period of time after the end of the recording operation, that is, whether or not effective scanning is restarted within a certain period of time. By doing so, continuous recording operations can be continued without loss time.

(Margin below)

[Brief explanation of drawings]

FIG. 1 is a system block diagram showing the relationship between the device according to the present invention and external devices, FIG. 2 is a schematic sectional view of the print control unit (printer) in the system diagram, and FIG.・-A schematic perspective view showing the relationship between the laser scanner unit and the recording photoreceptor, FIG. 4 is a schematic diagram showing the paper feeding section shown in FIG. 2, and FIG. 5 is a schematic diagram showing the paper ejection section in FIG.
・Schematic diagram showing an example; FIG. 6 is a plan view showing the operation panel section of the device of the present invention; FIG. 7 is an enlarged plan view of the display section in FIG. 6; FIG. 8 is an enlarged plan view of the data control section in FIG. A block diagram showing an example; FIGS. 9, 10, and 12 are format diagrams of data handled by the data control unit, and FIG. 11 is a correspondence between the area of the recording unit in the data control unit and paper. Figure 13 is a block diagram of the printing control section in Figure 1.
Figure 4 is a detailed circuit diagram of each detector in Figure 13, and Figure 15.
The figure is a block diagram showing details of the drive circuit and output element in Fig. 13, Fig. 16 is a circuit diagram showing details of the motor drive circuit and laser scan motor in Fig. 13,
Figure 7 is a detailed circuit diagram showing the laser modulation circuit and semiconductor laser in Figure 13, Figures 18 and 19 are characteristic diagrams showing the relationship between the semiconductor laser and optical output, and Figure 20 is a detailed circuit diagram of the circuit in Figure 17. Time chart for operation explanation, 2nd
1 is a detailed circuit diagram showing the beam detection circuit and beam detector in FIG. 13, FIGS. 22 and 24 are waveform diagrams for explaining the operation of the circuit in FIG. 21, and FIGS. B
) are front and side views showing an example of the structure of the beam detector, FIG. 25 is a detailed circuit diagram of the print data writing control circuit shown in FIG. 13, and FIG. 26 is an interface in FIG. 13. A circuit diagram of the circuit, FIG. 27 is a relationship between command abbreviations and functions used in the device of the present invention, and FIG. 28 is an explanatory diagram showing the contents of status used in the device of the present invention.
Figure 29 is a relationship diagram of the beam scanning position and data writing position on the recording photoreceptor in Figure 3, and Figure 30 is a diagram of the relationship between the beam scanning position and data writing position on the recording photoreceptor in Figure 3.
31 and 32 are time charts for explaining the operation of the circuit in FIG. 25, and FIGS. 33 and 34 are for the paper Printing pattern diagram, Figure 35 and Figure 3
Figure 6 is a characteristic diagram showing the relationship between exposure position, exposure energy, surface potential, exposure energy, and exposure position to explain the exposure control operation in the circuit of Figure 25, and Figure 37 is the high voltage power supply for charging in Figure 15. Detailed block diagram of 3rd
8 to 41 are characteristic diagrams for explaining the operation of the circuit in FIG. 37, FIG. 42 is a schematic diagram showing the relationship between the laser scanner unit and the recording photoreceptor in FIG. 2, and FIG. Explanatory diagram showing the relationship between the recording photoreceptor and paper, No. 4
Figure 4 shows a modification of the paper ejection tray shown in Figure 5.
Figures (A), (8) and Figure 46 are detailed diagrams of data recorded in each recording device in Figure 13, Figures 47 to 54, Figure 55 (Δ), ([3), (C). 56 and 60 are flowcharts for explaining the physical operation of the apparatus of the present invention, FIGS. 57 to 59 are time charts for explaining the operation of the apparatus of the present invention, and FIGS. 61 to 63 are flow charts for explaining the operation of the apparatus of the present invention. FIG. 3 is a relationship diagram showing display numbers and their contents in the device of the present invention. 1... External device, 2... Speed setting means, 175...
・Frequency divider, 180.181.182...detection element, 301...
Recording medium (recording photoreceptor), 312... polygonal rotating body, 3
13... Drive means, 500... Drive control circuit, 540... Frequency division ratio designation signal output line. Agent Patent Attorney Masayoshi Misawa

Claims (2)

[Claims] (1) A multifaceted rotating body that scans a medium with a beam, a driving means for rotating this multifaceted rotating body, a detection element that detects the rotation of this driving means, and a detection element that detects rotation of this driving means. a frequency divider for dividing the detection signal of the frequency divider, a drive control means for controlling the drive voltage of the drive means so that the output frequency of the frequency divider matches a reference frequency, and a frequency division ratio of the frequency divider. and speed setting means for outputting a frequency division ratio designation signal that specifies a frequency division ratio, and the speed setting means outputs a frequency division ratio designation signal that causes the drive means to be at a low speed when the beam is not scanning, and the speed setting means outputs a frequency division ratio designation signal that causes the driving means to be at a low speed when the beam is not scanning. A scanning device characterized in that the driving means outputs a frequency division ratio designation signal that increases the speed. (2) The speed setting means has a timing means that starts timing after the end of the effective scan, and even after a certain period of time has elapsed, the speed setting means continues.
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2. The scanning device according to claim 1, wherein the scanning device outputs a frequency division ratio designation signal that increases the frequency.