JPS63213496A - Recorder - Google Patents

Abstract

PURPOSE:To smoothly start a pulse motor by a relatively small power even in its restart by interrupting the recording operation at a point except the maximum load torque. CONSTITUTION:When a continuous printing is conducted, a sheet feeding roller 402 might detect a paper jam according to a printing interval during rotation. A CPU turns ON a sheet feed solenoid drive signal at this time, simultaneously monitors the roller 402-rotating time (tc), and interrupts the sheet conveying drive after the time tc with respect to paper jam generated from the drive signal ON to the time tc. Accordingly, even if the paper jam occurs at any time, the roller 402 is always placed at a normal rotary position. Thus, the motor for driving the roller 402 can be restarted by a small torque.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a recording device that drives a load using a pulse motor.

[Prior art]

Conventionally, in this type of recording apparatus driven by a pulse motor, if a paper jam or failure is detected during recording operation, the drive apparatus is immediately stopped. However, if the load torque is the maximum when the recording operation is interrupted, the load torque will remain at the maximum even when the drive device is restarted after the cause of the recording operation interruption is removed.

The pull-in torque of a pulse motor is smaller than the pull-out, and if you try to start the pulse motor against the maximum load torque, you will need a very large amount of power, and if the pull-in torque is insufficient, the pulse motor will step out. The drive unit will not be able to start up.

〔the purpose〕

The present invention has been made in view of the above points, and it is an object of the present invention to provide a recording device that allows the device to restart smoothly.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a control circuit diagram of the laser beam printer in this embodiment, and in the figure, 201 is a one-chip microcomputer with built-in ROM (hereinafter referred to as CPU 201).
, ANO to AN7 are analog input cabotos, PA3
~PA7. PBO~PB7. PO2 is input port, PA
O, PA2. PCO~PC2, PC4~PC7゜PDO
NPD? , PFO to PF7 are output ports. 202
is a controller that receives signals from the host computer 213 and controls image formation for the printer. 20
4 is a pre-exposure lamp that uniformly erases the potential on the photosensitive drum 1008; 205 is a high-voltage unit that generates high voltage in response to a high-voltage drive signal from the CPU 201; and 206 is a high-voltage unit that contains toner and generates an image by receiving the laser from the semiconductor laser LS 201. 207 is the CPU 201
This is a fixing heater drive circuit that receives a fixing heater drive signal from the fuser heater drive circuit and turns on and off the gate of the triac Trl. 208 is the same as 201 (one-chip microcomputer with built-in ROM (hereinafter referred to as CPU 208),
In response to a control signal from the CPU 201, the amount of laser light and the drive of the pulse motor (Ml) are controlled. 209 is CPU20
a polygon motor drive circuit that receives a polygon motor drive signal from 1 and rotates the polygon motor M3 at a constant speed;
0 is a laser circuit that receives a laser drive signal from the CPU 208 and a laser control signal from a gate array 212, emits and receives a laser beam, and feeds back the amount of laser light to the CPU 201; 211 is the light received by the optical fiber 1009 in FIG. 10; This is a beam detection circuit that inputs the signal to the gate array 212. 212 is CPU20
The image width information sent from 8 and the controller 202.
A gate that controls the on/off of the laser according to the image signal during image formation, and monitors the polygon motor and beam detect signal in response to the beam detect signal and the signal from the polygon motor drive circuit. It is an array. Although the gate array 212 is shown separately as 212a and 212b in FIG. 1, they are actually composed of the same chip. In addition, the part surrounded by dotted lines in FIG. 1 corresponds to the control section (print controller) excluding the sensor and drive system.

FIG. 2 is a diagram showing a connection state between a low voltage source and a print controller.

In Figures 1 and 2, when the power switch of 5W181 is turned on, +5V is first output from the low voltage power supply of 101.
At the same time, a reset signal RESET (
A signal (hereinafter referred to as RESET signal) is output.

In response to the RESET signal, the CPU 201 starts control,
After completing the initialization of each unit of the main body, it is necessary to notify external devices such as the controller of the 202 that the power of the main body has been turned on (printer power ready signal PPRDY).
(hereinafter referred to as PPRDY signal). This PP
The RDY signal is also connected to the low voltage power supply 101 at +24VA, +
24VB and -5V output control signal REMOTE (
This signal is output as a REMOTE signal (hereinafter referred to as a REMOTE signal). The low voltage power supply 101 outputs +24V and -5V when this REMOTE signal becomes true.

The CPU 201 that outputs the PPRDY signal then outputs the motor drive signal DRMD to the CPU 208 for a certain period of time, during which time the CPU 208 outputs an excitation signal for the pulse motor.

In response to this, the low voltage power supply 101 initially rotates the pulse motor Ml, which is the drive motor of the paper conveyance system.

This is the photosensitive drum 1008 inside the EP cartridge 206.
This is to improve the fit between the gear of the paper conveyance system and the gear of the paper conveyance system. At this time, the CPU 201 connects the clutch 405 shown in FIG. 4 by outputting the registration solenoid drive signal REGD, and the registration roller 4 is driven by the motor.
Rotate 04. If there is residual paper in the paper transport unit and the initial rotation of the remote motor can transport the residual paper to the position of the paper ejection sensor PS201, the CPU 201 will detect that there is residual paper in the machine and automatically eject the remaining paper. , or a paper jam, which indicates to the operator that there is residual paper in the machine. In addition, the motor drive signal DRMD
is used together with the polygon motor drive signal 5CNON and the pre-exposure lamp drive signal PEXP, so the polygon motor M3 and the pre-exposure lamp 204 are also driven at the same time as the initial rotation of the motor. However, during this initial rotation of the motor, the laser is not output even if the polygon motor M3 starts up, so the beam detect signal nD indicating the beam scanning position is
(hereinafter referred to as BD signal) is not monitored.

After the initial rotation of the motor is completed, the CPU 201 detects the amount of toner remaining in the EP cartridge 206. first,
The high pressure unit 205 transfers the developing bias A from the CPU 20I.
C-minute drive signal DBAC (hereinafter referred to as DBAC), transfer high voltage drive signal HVTON (hereinafter referred to as HVTON signal)
and supplies a developing bias into the developing cylinder. At this time, the remaining toner amount detection sensor 220 installed inside the cartridge 206 detects the remaining amount of toner, and the high pressure unit 206 detects the remaining amount of toner.
5, the CPU 2 outputs the toner sense signal TSENS.
It is input to analog input port 01.

The control program of the CPU 201 does not detect the remaining amount of toner at the same time as outputting the high-voltage drive signal, but rather maintains a certain period of time and performs the detection after the high-voltage output has sufficiently risen. Further, the remaining amount of toner is detected also during printing operation, and the print signal PR from the controller 202 is detected.
NT (hereinafter referred to as PRNT signal), the primary high voltage P, the DC portion of the developing bias DB, and the transfer high voltage T are output from the high voltage unit 205 in this order, and for a certain period of time after the AC portion of the developing bias DB rises. Afterwards, toner remaining amount detection starts and ends at the same time as the DBAC signal from the CPU 201 is cut off. Since the remaining toner amount detection signal TSEMS fluctuates with each rotation period of the photosensitive drum 1008, the CPU
The control program 201 performs a detection method as shown in FIG. In FIG. 3, in step 300, it is determined whether or not the remaining amount of toner can be detected. If it is possible, the process proceeds to step 301. Already in step 301 the LED
When the insufficient remaining amount of toner is displayed by 200, no new detection of the remaining amount of toner is performed. No in step 301
If so, in step 302, counter 1 for determining whether or not the remaining toner amount is insufficient is reset. Next step 303. Step 3
At step 04, the average value counter 2 and buffer of the remaining toner amount detection signal are cleared. Next, if the continuous reading is not completed N times in step 305, the remaining toner amount detection signal TSENS is read in step 306, the integrated value is saved in the buffer in step 307, and counter 2 is counted in step 308. The process returns to step 305. If it has been read N times in step 305, step 30
Find the average value in step 9. The result is compared with a reference value for insufficient remaining toner, and if it is determined in step 310 that there is insufficient remaining toner, a counter l for determination is incremented in step 311. Step 3 if there is not enough toner remaining
Returning to step 02, the remaining amount of toner is detected again. Step 3
When the counter l counted up in step 11 reaches M times in a row, in step 313 the LED 200 is used to display the insufficient amount of toner remaining.

If it is not M times in a row, the counter is left as is, and the remaining toner amount detection is read again from step 303.

As described above, by taking the average value of the remaining toner amount detection signal TSEM and further determining whether the remaining amount of toner is insufficient M times consecutively, it is possible to cope with fluctuations in the remaining toner amount detection signal TSENS every 1008 cycles of the photosensitive drum, and moreover, it is ambiguous. It is possible to obtain a judgment result that is accurate. In addition, once the toner remaining amount is insufficient, once the cartridge 206 is replaced, the CPU 20
It is held until 1 makes a decision. A determination as to whether the cartridge 206 should be replaced is made as follows. FIG. 11 is a schematic diagram of the laser beam printer of this embodiment. In FIG. 11, the upper door 110 of the printer 401
Low-voltage power supply 1 interlocked with lever 1103 attached to 1
The micro switch 5W100 in 01 is the upper door 110
It turns off at the same time as 1 is opened, cutting off 24VB and motor drive 17) 24V power supply. CPU201 is the same 2
4VB・signal DC2,1' (hereinafter referred to as DC24
It detects that the DC 24v signal has become low level and determines that the upper door 1101 is opened. Since the upper door 1101 must be opened in order to replace the cartridge 206, the CPU 201 can predict that the cartridge 206 will be replaced when the upper door 1101 is opened.

Except under the conditions described below by opening the upper door 1101,
In order to ensure the safety and control reliability of the printer 401, the CPU 201 jumps to the beginning of the program to reset its own processing and redoes the b-period setting. At this time, the display of the insufficient amount of toner by the LED 200 is also reset, and after the upper door 1101 is closed, the first remaining amount of toner is detected again after the initial rotation of the motor.

When the upper door 1101 is closed, the lever 1103 attached to the upper door 1101 pushes the micro switch 5W100 in the low voltage power supply 101, and the CPU 20
24v is output from the low voltage power supply 101 which receives the REMOTE signal from microswitch 5.
Considering chattering caused by turning on and off the W100, or the fact that the upper door 1101 is incompletely closed due to operator error, the CPU 201 immediately starts up the printer 401 even if the DC 24V signal becomes high level. Wait until the upper door 1101 is completely closed after leaving the blank for a certain period of time before turning on the printer 40.
Launch 1.

Since the control program is reset when the upper door 1101 is opened, the PPRDY signal becomes false, but since +v5 from the low-voltage power supply 101 is rising, after the control program is reset, the PPRDY signal becomes false when the upper door 1101 is opened. I'll come back though. Therefore, the controller power ready CPRDY signal output from the controller 202 (
If the CPRDY signal (hereinafter referred to as CPRDY signal) is true, communication with the controller 2'02 is also possible. At this time, if there is a status request from the controller 202, the printer 401 replies to the controller 202 with the status that the upper door 1101 is being opened.

After the initial rotation of the motor Ml and the detection of the remaining amount of toner, the printer 401 enters a warming-up state.

At this time, if the controller 20°2 is connected, the printer 401 returns a status of Waiting in response to the status request from the controller 202. During warming up, the temperature of the fixing heater H1 of the fixing device 413 is adjusted.
The fixing roller 411 is heated to standby temperature T1. A pulse signal of the fixing heater drive signal FSRD (hereinafter referred to as FSRD signal) is sent from the CPU 201 to the power input section 20.
7, and the power input section 207 is output to the triac Trl.
is driven to heat the fixing heater H1. When the fixing roller 411 reaches the standby temperature T, the main body enters a stop state and returns the information to the controller 202.The wait status is canceled and the CPU 2 waits until the print operation starts.
01 controls the fixing heater H1 so that the standby temperature T is maintained. The printer 401 is the controller 202
Cassette paper feeding or manual paper feeding can be performed using a paper feeding mode designation command from . If no paper feed mode designation command is sent, the printer assumes cassette paper feed mode. In case of cassette paper feeding mode, when the following conditions are met, the controller 20
If the PRNT signal from 2 becomes true, the printing operation is started or continued.

(1) The EP cartridge 206 is set.

(2) The controller power ready CPRDY signal is true.

(3) No paper jam occurs.

(4) There is no failure or misprint in the fixing device, polygon motor M3, or beam detect signal BD.

(5) The cassette 408 is installed and paper is set inside.

The presence or absence of the EP cartridge 206 is determined by another control CPO 208 in the printer, and the drum sensitivity sensing frame 1102 of the EP cartridge 206 is controlled by a micro switch 5.
It is determined by turning on W210 and 5W211, and if there is no cartridge 206, it sends an EP cartridge no signal N0CRT (hereinafter N0C
RT signal) is output. If the N0CRT signal is false, the EP cartridge 206 is present.

The controller power ready signal CPRDY is a signal input from the controller 202.
This is the only signal that can detect the rising state of 02.

In (3) and (4) above, except for the fuser failure, printer 4
This is a condition that can be detected only when a print operation is performed at least once after 01 rises, and polygon motor failure occurs even if a certain period of time has passed after polygon motor drive signal 5CNON becomes true. The motor M3 does not rotate at a constant speed, and the polygon motor ready signal 5CNRDY (hereinafter referred to as 5CNRDY) from the polygon motor drive signal 209
signal) does not become true, or 5CN
This is a case where the RDY signal once becomes true and then remains in color for a certain period of time.

The misprint is due to an abnormality in the BD double signal obtained by the rotation of the polygon motor M3, and the CPU 201
Signal 13DERR (hereinafter referred to as BDERR signal) indicating that there is a D-fold signal abnormality: Judged when true is input, and furthermore, if the BDERR signal continues for a certain period of time, BDERR signal is detected.
D It is judged as a failure. Fuser failure is caused by thermistor Tl (l
The signal FSR of the temperature Tx of the fixing roller 411 detected by
TH (hereinafter referred to as FSRT I signal) is input to the CPU 201 and the FSRTH signal is outside the control temperature range, or when it is determined that the thermistor TH1 is disconnected or the fixing heater H1 is disconnected. It is. When the fuser malfunctions, the CPU 201 sends a signal FSERER signal (hereinafter referred to as FSERER) indicating that the fuser malfunction has occurred.
A signal (referred to as a signal) is output and charged up to the capacitor C211. The charge that has been charged up in the capacitor C211 is gradually discharged after the power is turned off, but if the power is turned on before reaching a certain level, it is determined that the fixing unit has failed again, and the charge is charged up in the capacitor C211 by the FSERER signal. The paper jam state is determined when a paper jam occurs based on jam detection timing, which will be described later.

As shown in FIG. 4, the paper cassette 408 has a top 412 attached to the tip of the paper cassette that turns on any one of the microswitches 5W201 to N5W203 to control the CPU 201 from PSIZEI to PSIZE3.
is input as a signal, and it is determined that a paper cassette is present. The position of the paper cassette frame 412 differs depending on the paper size handled, so microswitches 5W201 to 5W203 are
It is possible to detect up to 7 different paper sizes by determining whether this is on or off. Further, the presence or absence of paper in the paper cassette 408 can be detected by determining the signal PEMP from the paper sensor PS202.

When all of the above conditions are satisfied and a printable state is reached, a printable signal RDY (hereinafter referred to as RDY signal) is sent from the printer 401 to the controller 202. Further, if the above-mentioned conditions are not satisfied, the printer 401 can return the status of the above-mentioned conditions to the controller 202 as a status if there is a status request from the controller 202.

When a manual paper feeding command is sent from the controller 202, the printer 401 enters the manual paper feeding mode from printing the next page, and becomes ready for printing when the following conditions are met. Conditions (1) to (4) for printing in the cassette paper feeding mode described above are satisfied, the paper cassette 40B is installed, and paper 407 is set in the manual feed slot.

In FIG. 4, manual paper feeding is performed by feeding paper 407 along a manual feeding guide 406 on a paper cassette 408 to a paper feeding roller 4.
Paper cassette 4 must be inserted up to 02.
The structure is such that manual paper cannot be set without 08. Therefore, the CPU 201 first detects that the paper cassette 408 is installed using the paper cassette size detection signal PSIZEI-PSIZE3, and then detects the signal MPFS (hereinafter referred to as MPFS signal) from the manual paper detection sensor PS203 located at the manual paper feed port. ) is input to determine the presence or absence of manual paper. In the manual paper feed mode as well as in the cassette paper feed mode, the controller can return the print enable signal RDY or, if printing is not possible, the status.

FIG. 14 is a flowchart showing the determination of the presence or absence of paper depending on the above-mentioned paper feeding mode. In step 1401, the presence or absence of a paper feed cassette (related to the paper feed mode) is first determined based on the paper feed cassette size signal PSIZEI~3, and if there is a paper feed cassette, then in step 1402, whether or not the paper feed mode is manual If it is the manual paper feeding mode, the presence or absence of manual paper is determined in step 1403 based on the MPFS signal, which is a manual paper detection signal.

If there is paper, the controller 202 at step 1404
reset the paperless bit in the status sent to
If there is no paper, the paper out bit of the status is set in step 1408. Other printability conditions are checked in step 1405, and if printing is possible, the ready display is turned on in step 1406, and if printing is not possible, the ready display is turned off in step 1409. If the cassette paper feeding mode is selected, the presence or absence of paper in the cassette is determined in step 1407 based on the cassette paper detection signal PEMP. The subsequent procedure is the same as in manual paper feeding mode.

However, the analog input port RDYIN of the CPU 201
By setting the H signal to a low level using the SW 212, it is possible to check among the above-mentioned printable conditions such as presence or absence of the EP cartridge 206, presence or absence of paper jam, malfunction of the polygon motor or beam detect signal, misprint,
It is possible to set the printable state regardless of the presence or absence of the paper cassette 408 and the presence or absence of paper in the paper cassette. However, in the manual feed mode, printing is possible, and even if the print signal PRNT from the controller 202 is received, the printing operation will not start unless there is paper in the manual feed slot and the MPFS signal becomes true. Furthermore, even if the printable condition ignored signal RD\INH is set to low level to create a printable state, the above-mentioned conditions will continue to be detected, and if a printer status request is made from the controller 202, the detected results will be Return as status. This also applies before, during, and after the printing operation. After the printer 401 becomes ready for printing, when the controller 202 sends out the print signal PRNT, the CPU 201 receives it and controls the printing operation in the sequence shown in FIG. First, the motor drive signal DRMD° is set to true, and the paper transport motor M
Drive l. At the same time, polygon motor drive signal 5CNO
N, set the pre-exposure lamp drive signal PEXP to true. After that, -th high voltage HV I ON, developing bias DC minute DB
Each high voltage drive signal of DC and transfer high voltage HV T ON is turned on in sequence.

Furthermore, 10 seconds after the motor is driven, the paper feed solenoid 5L2
01 (paper feed drive signal CPUD (hereinafter referred to as CPU
D signal) is true. True period t of CPUD signal
cr'u is shorter than the time tc for the half-moon-shaped paper feed roller 402 to rotate once, but when the paper feed solenoid 5L201 is driven and the paper-feed clutch 410 is connected, the half-moon-shaped paper feed roller 402 rotates once and feeds paper. It is rotated by the driving force of the paper conveyance system until the clutch 410 is disengaged.

After turning on the CPUD signal, the CPU 201 sends a laser power control start signal APC3T (hereinafter referred to as A) to the CPU 208 in order to perform laser power control after confirming that the polygon motor is ready.
PC3T signal) is output. The CPU 208 is an AP
Upon receiving the C3T signal, the laser power is controlled by input/output to the laser drive circuit 210 to maintain a constant level. At this point, the printer is ready for image formation.

Next, the CPU 201 instructs the controller 202 to
Time t from D signal on. After that (variable depending on the rise condition of the polygon motor), a vertical synchronization signal request VSREQ (hereinafter referred to as the VSREQ signal) is output. controller 20
When the image output preparation is completed from 2, the vertical synchronization signal VSYN
C (hereinafter referred to as a VSYNC signal) is returned, and the CPU 201 is in a waiting state during that time. If the print signal becomes false during this time, the CPU 201 determines that printing has been canceled and enters post-processing of the printing operation to output a blank page. When the vertical synchronization signal VSYNC is sent from the controller 202, the CPU 201
In order to drive the registration roller driving solenoid 5L202 after a certain period of time t2 based on the leading edge of the NC ON signal,
Drive signal REG for registration solenoid 5L202
Make D signal true. Further, after t3 from the leading edge of the VSYNC signal being turned on, the DBAC signal is made true to drive the developing bias AC.

Furthermore, the image mask signal TOPER3 in the sub-scanning direction is set to VS
It turns off t4x seconds after the leading edge of the YNC signal and turns on t4 seconds depending on the paper size. While the both image mask signals TOPERS in the sub-scanning direction are on, the controller 2
Even if the image signal VDQ is input from 02, no image is formed because the laser is not output.

The paper conveyed by the registration roller drive reaches a paper discharge sensor PS201 installed near the fixing device. Therefore, the CPU 201 outputs the signal PDP (
It detects that the PDP signal (hereinafter referred to as PDP signal) is true and confirms that the paper has been correctly fed and conveyed. If V
If the FDP signal is false after a time t from the leading edge of the SYNC signal being turned on, it is determined that there is a delay jam. When the image signal transmission from the controller is finished and time t6 elapses from the leading edge of the VSYNC signal on, if the printer is in a printable state, the print request status is changed to recognize that it is possible to receive the next PRNT signal. Set. After transmitting the image signal, the controller 202 may make this status request and make the PRNT signal true. CPU201 is VS
If the next PRNT signal is not sent from the controller 202 by the time t7 after the leading edge of the YN (J" ON signal, or if the printer is no longer in a printable state, the printing operation will begin post-processing. If the PRNT signal is not sent by the time t7) If the signal becomes true, the print sequence from the CPUD signal on as described above is taken again.From the leading edge of the VSYNC signal on,
After time t8, the paper on which the image has been formed is transferred to the paper discharge sensor PS2.
Since it should have passed through 01, the CPU 201 is V.
Since the PDP signal is false after a time tT from the leading edge of the SYNC signal, it is confirmed that the paper has correctly passed through the paper discharge sensor PS201. If the FDP signal is true at this time, the CPU 201 determines that a retention jam has occurred. Normally, when a paper jam occurs, the paper transport drive is immediately interrupted,
A jam status is set to make the controller 202 recognize that a jam has occurred. However, when continuous printing is performed, a paper jam may be detected while the paper feed roller 402 is rotating depending on the printing interval. At this time, the CPU 201 turns on the paper feed solenoid drive signal CPUD and at the same time monitors the time tc for one rotation of the paper feed roller 402, and the time tc from the CPUD signal on.
Regarding paper jams that occurred during the time tc.
Afterwards, the paper transport drive is interrupted. The same goes for setting paper jam status. Therefore, no matter when a paper jam occurs, the paper feed roller 402 is always placed at the normal rotational position.

FIG. 13 is a flowchart showing the paper feed control and jam control described above.

If the print timer is on in step 1201, the print sequence is already in progress, so the process moves to step 1205. If the print timer is off in step 1201, the process moves to step 1202, and in steps 1202 and 1203, the PRNT signal is true. If the printer is ready to print, the print timer is turned on in step 1204. Otherwise, the timer is reset at 12 (step 1205 is the paper feed timing, and the paper feed timer is started in step 1206. After that, the print timer is turned on in step 1204. If a jam occurs during control, the jam flag is turned on only in step 1208 without handling the jam on the spot.After performing other control checks, step 1
If the jam flag indicating the occurrence of a jam is on in step 209, it is determined in step 1210 whether the paper feed timer is running. This paper feed timer is started at the time of paper feeding in steps 1205 and 1206, and counts the time tc during which the paper feed roller 402 is rotating, and is then cleared. If the paper feed timer is on in step 1210, the paper feed roller 402 is rotating, so the jam processing in step 1211 is not performed, and the paper feed roller 402 is rotated.
After the time tc at which the printer has stopped, the jam processing in step 1211 is performed. Jam processing involves resetting the timer, stopping the conveyance system, and setting the jam status.

If paper cassette 4 is inserted during image formation in cassette paper feed mode,
Even if the paper sensor PS202 in 08 indicates that there is no paper, or the microswitch 5W201-8W203 indicates that there is no cassette, the paper currently being formed is already being conveyed, and furthermore, the controller 202 The image being formed must be guaranteed. Therefore, the time from the leading edge of the vertical synchronization signal VSYNC signal ON for image formation to the end of image formation on the trailing edge of the paper is 1. -1
．． Until then, it does not sense the presence or absence of the paper cassette 408 or the presence or absence of paper in the paper cassette. Also from time t, -ty to time t.

Until then, even if no paper or no paper cassette is detected, the RDY signal indicating that printing is possible is maintained true, and after time t9, the RDY signal is made false. The same applies to the printable display. In addition, there is no paper cassette when in manual paper feed mode.
Alternatively, even if there is no manual paper, the RDY signal remains true until image formation is completed.

Similarly, even if the paper cassette 408 is removed during image formation and a paper cassette of another paper size is inserted, the paper size remains the same from the leading edge of the VSYNC signal on until time t before the paper size is switched. The front paper size should also be guaranteed to the controller 202 (paper size status is set).

The process is the same as when switching paper cassettes during image formation (even if the paper feeding mode is switched during image formation, the paper feeding mode and paper size before switching are guaranteed until the image formation is completed).

When a manual paper feeding command is output from the controller 202, the printer 401 enters manual paper feeding mode.

In the manual feed mode, if the print is possible as described above, the print signal PRN from the controller 202 is
T starts the print operation. If, as shown in Figure 6, the print signal PRNT signal is true and the printable conditions other than manual feed paper detection are in place, if paper is inserted into the manual feed slot, the printable conditions are in place and printing begins immediately. However, the printer's paper feeding operation
That is, the rotation of the paper feed roller 402 by the paper feed solenoid drive signal CPUD starts at time t1 from the completion of manually fed paper detection.
゜Do it later. Actually, the high voltage drive signal is HVTON, DB
D.C.

After the timing to make HVION true is completed, the CPU
D signal: becomes true. In the case of continuous printing by manual paper feeding, the paper feeding operation of the printer is performed tlo after manual paper detection is completed. The vertical synchronization signal VSY of the previous page is detected at a certain timing during the elapse of time t1° from the completion of manual feed paper detection.
When the leading edge of NC ON coincides with time t7, no post-processing of the print operation is performed, the CPUD signal is turned on after time tlO, and the print operation for the next page is directly started.

In the case of cassette paper feeding, there is a universal cassette that allows you to freely set the paper size set in the paper cassette 408, and can also feed envelopes and other thick paper. Also, in manual paper feeding, the paper width of the manual paper guide 406 of the paper cassette 408 can be varied, allowing envelopes and other thick paper to be fed. When using this universal cassette paper feeding mode or manual paper feeding mode, the CPU 201
When printing the next page, the vertical synchronization signal request signal VSREQ is sent from the paper feed solenoid drive signal CPU 201:
The time until the end is the time t when feeding paper from a normal cassette. Control is performed to further extend the time tw. In the first case, as shown in FIG. 6, printing is possible, and the paper feeding mode is universal cassette feeding or manual feeding, and the first sheet is printed by receiving the print signal PRNT from the controller 202. . The second and subsequent sheets are the same as the normal cassette feeding mode. The second case is when the paper cassette 408 is switched to the universal cassette during printing in the normal cassette paper feeding mode, or when the controller 202 sends a command to switch the paper feeding mode to the manual paper feeding mode. At this time, C
PU201 is the VSY of the page before switching as shown in Figure 7.
From the leading edge of the NCF signal ON until time t7, neither the next print signal request nor the paper feeding operation is performed, and after time t7 when the paper feeding mode is switched, the printing operation from the first sheet is controlled again.

The third case, as shown in FIG. 8, is when the printer is in a state where it can print by universal cassette paper feeding or manual paper feeding during post-print processing and receives the print signal PRNT from the controller. In the above three cases, the time required to print one sheet is longer than when feeding paper from a normal cassette.
only becomes longer. This time tw is the time required to store additional heat in the fixing device. When the printer displays an insufficient amount of toner or a paper jam occurs, the operator opens the upper door 1101 to deal with the problem.
Upper door! As described above, by opening 101, the control program of CPU 201 is temporarily reset. In addition, the controller power ready signal CPRD
Also when Y becomes false for a certain period of time, it is determined that the controller is down and the control program of the CPU 201 is temporarily reset. However, if the printer has already experienced a major failure such as a fuser failure, a polygon motor failure, or a beam detection signal detection failure when the upper door 1101 is opened, the control program will not be reset. Maintain failure mode.Also CPRDY
If the aforementioned delayed jam has already occurred in the printer when the signal becomes false for a certain period of time, the control program maintains the paper jam mode without being reset.

The above control sequence is as shown in FIG. If it is detected in step 901 that the upper door 1101 is open, it is determined in step 902 whether a failure has occurred. A failure can be determined by making the controller 202 recognize the failure as soon as the printable status signal RDY becomes false when the failure occurs (failure information is set in the status, so it can be determined by referring to the status). If there is a failure, control is performed during upper door oven in step 911, and the process moves to the next control.If there is no failure, reset preprocessing is performed in step 905.If it is not the upper door oven in step 901, step 903
It is determined whether the CPRDY signal has been false for a certain period of time, and if the controller is not down, the next control is executed. If the controller is down, it is determined in step 904 whether a delay jam has occurred. If a delay jam has not occurred, the process moves to step 905. There are two types of paper jams: the delayed jam mentioned above and the retained jam.
By setting a flag according to each detection timing, it is possible to determine which jam occurs. If there is a delay jam in step 904, the process moves to the next control. In step 907, a failure determination is made again, and if it is a failure, in step 908, the failure status is set again and other processing is performed. In step 909, the paper jam is determined again, and if the paper is jammed, the jam status is set and other processing is performed again. In the pre-reset process at step 905, if there is any necessary information after reset, the information is set in the RAM area of the CPU 201, jumps to the beginning of the control program at step 906, and is set by initializing the control program. .

Further, in the process in the upper door oven at step 911, the fixing heater drive signal FSRD (hereinafter referred to as FSRD signal) is turned off so that the fixing heater H1 is not driven. Furthermore, in the fixing heater control process in step 912, even if the FSRD signal is off, the thermistor TH
The control maximum value TmIIx of the temperature Tx of the fixing roller 411 based on the input of I is monitored. Therefore, the upper door 110
This means that the temperature Tx of the fixing roller 411 continues to be monitored even when the fixing roller 411 is opened.

FIG. 1.2 is a time chart showing the determination of activation and failure of the polygon motor M3.

When the 5CNON signal that starts the polygon motor M3 in response to the PRNT signal becomes true, the rotational speed of the polygon motor M3 increases. When the rotation speed approaches the specified rotation speed,
5CNRDY signal comes out.

When the polygon motor M3 locks in, hunting occurs and the rotational speed fluctuates around the specified rotational speed, so the 5CNRDY signal becomes intermittent.

Let this hunting period be t3. CPU201 is 5C
tb longer than ta from the time the NRDY signal becomes true once
Monitor the wait time CNRDY signal.

When the 5CNRDY signal becomes completely true during this time tb, it is determined that the polygon motor M3 has reached the specified rotation speed, and the VSREQ signal is output.

If the polygon motor M3 is hunting during the tb time, it is determined that the polygon motor M3 has not yet reached the specified rotation speed during the tb time, and the next tb dark time monitoring is started. If the CPU 201 does not determine that the specified rotation speed has been reached within the time tc after the 5CNON signal becomes true, it is determined that the polygon motor M3 is malfunctioning. When it is determined that the polygon motor M3 is malfunctioning, the paper that was previously fed by the paper feed roller is ejected out of the machine.

〔effect〕

As explained above, according to the present invention, since the recording operation is interrupted at a torque other than the maximum load torque, the maximum load torque is not reached even when restarting after the recording operation interruption factor is canceled, and the pulse motor is operated at a relatively low power. You can start it up smoothly.

[Brief explanation of the drawing]

Figure 1 is a control circuit diagram of the laser beam printer in this embodiment, Figure 2 is a relationship diagram between the low voltage power supply and printer controller, Figure 3 is a flowchart of the remaining toner amount detection method, and Figure 4 is a paper cassette and paper feed. Structure of the rollers, Figure 5 is a timing chart for normal cassette paper feeding, Figures 6, 7, and 8 are timing charts for universal cassette paper feeding or manual paper feeding, and Figure 9 is for when the top door is open. , a flowchart of part of the control method when the controller is down, Figure 1O is a schematic diagram of the laser scanning system, Figure 11 is a diagram of the main body when the upper door is opened, Figure 12 is the determination of activation of polygon motor M3 FIG. 13 is a flowchart showing paper feed control and jam control in this embodiment. FIG. 14 is a flowchart showing cassette mode and manual feed mode in this embodiment. 202: Controller or host computer, 20
4: Pre-exposure lamp, 205: High pressure unit, 206: E
P Cartridge, 207: Roasting heater drive circuit, 2
09: Polygon motor control, drive circuit, 21O: Laser drive circuit, 211: BD circuit, 212 Nigade array, 213: Reset circuit, R100 to R999: Resistor C
100~C999: Capacitor, 5W100~5W39
9: Switch, IC100~IC999: IC5PS
200~PS299: Photo sensor, l-11: Fixing heater, THI: Thermistor, 5L201~Sl, 20
2, Solenoid, TP200: Thermoswitch, Tr
i:,) Liac, Q100 to Q999: Transistor, Ml, M3: Motor, LS201: Semiconductor laser, 401 Ni printer main body, 402: Paper feed roller,
406: Manual feed guide, 404 Ni registration roller, 40
5 Clutch for registration roller, 407: Paper, 408
: Paper feed cassette, 409: Paper sense lever, 410:
Paper feed roller clutch, 411: Fixing roller, 1001
: Polygon mirror, 1003: Collimator lens, 10
04 Nijilintorical lens, 1005: Imaging lens,
1006: Beam detect mirror, 1007: Reflection mirror, 1008: Photosensitive drum, 1009: Optical fiber, 1101: Upper door, 1102 + frame for detecting sensitivity of photosensitive drum, 1103: 5W100 on/off lever.

Claims (1)

[Claims] In a recording device that drives a load with a pulse motor and is capable of detecting a cause for interrupting the recording operation, if the cause for interrupting the recording operation occurs when the load torque is approximately at a maximum, the recording device continues the recording operation and A recording apparatus characterized by comprising a control means for interrupting recording operation when the load torque is no longer approximately at its maximum.