JPH08241023A - Electrophotographic printer - Google Patents

Abstract

PURPOSE: To eliminate such failure that a power saving control action is executed while printing information is still held by a buffer by changing at least either of first and second set time by a set time change means. CONSTITUTION: When a signal is not received from an external equipment for the first set time or more, the power saving control action is executed. When such a state that the printing information is held by the buffer for the second set time or more is continued, the printing information is printed. When the first set time is equal to the second set time or the second set time is longer than the first set time, the second set time set to a time-out printing timer 52 is written and stored in a save memory 54 first. Next, the time one second shorter than the first set time in a power-save timer 51 is calculated and set to the timer 52 as the second set time. That means, the second set time with respect to the timer 52 is automatically corrected to the time one second shorter than the first set time in the timer 51 from the time saved in the save memory 54.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic printer having an electrophotographic printing process.

[0002]

2. Description of the Related Art Generally, an electrophotographic printer forms an electrostatic latent image based on information to be printed on the surface of the photoconductor by exposing it after uniformly charging the photoconductor. Toner, which is a developer, is adhered to develop, the developed toner image is transferred to a transfer paper, and then the transfer paper is thermally fixed by a heat fixing device to perform printing.

Such a printer is connected to a host computer, which is an external device, through an interface, receives information created or read by the host computer as print information, and temporarily stores it in a buffer.
Printing is performed by controlling each unit based on the print information in the buffer.

Conventionally, in the electrophotographic printer of this type, if the power save mode is set on the operation panel provided in the printer, the signal reception from the host computer is maintained for a certain period of time. It has been known that the printer automatically enters a power save mode to perform power saving control by, for example, stopping or reducing the power supply to the heater of the thermal fixing device that consumes a large amount of power.

[0005]

A printer in which print information received from a host computer via an interface is temporarily stored in a buffer and each unit is controlled based on the print information in the buffer to perform printing. In some cases, if the print information is retained in the buffer for a certain period of time due to a failure such as paper out or paper jam, after the failure is recovered, the print information is automatically printed based on the print information. Some have a time-out printing means for making them empty. Therefore, it has been considered to add the time-out printing means to the electrophotographic printer.

However, when the above-mentioned time-out printing means is added to the electrophotographic printer capable of setting the power save mode, a fixed time required to enter the power save mode, that is, a state in which no signal is received from the host computer, is set. If the fixed time required for the time-out printing means to operate is set longer than the duration, that is, the duration for which the print information is held in the buffer is set longer, the power saving is performed before the time-out printing means operates. Since the mode is entered, there is a problem that automatic printing cannot be performed by the time-out printing means until the power save mode is released.

The present invention has been made under such circumstances, and an object of the present invention is means for performing power saving control when a signal continues to be received from an external device for more than a first set time. And a means for printing the print information when the print information is held in the buffer for a second set time or longer continues, the power saving control is started while the print information is held in the buffer. It is an object of the present invention to provide an electrophotographic printer which can be prevented.

[0008]

SUMMARY OF THE INVENTION According to the present invention, print information received from an external device through an interface is temporarily stored in a buffer, the photosensitive member is uniformly charged, and then the print information is exposed based on the print information in the buffer. An electrostatic latent image is formed, a developer is attached to the electrostatic latent image for development, the developed image is transferred to transfer paper, and then the transfer paper is thermally fixed by a heat fixing device to perform printing. A means for controlling power saving when a signal is not received from an external device for a first set time or longer, and a print information is held when a print information is held in a buffer for a second or longer set time. In an electrophotographic printer that also has a unit for performing printing of a set time, a set time changing unit that changes the first set time and the second set time, and a first set time or a second set time by the set time changing unit. of Setting time comparing means for determining whether or not the second setting time is longer than the first setting time due to the change of the constant time, and the second setting time is longer than the first setting time by the comparing means. And a setting time automatic correction means for correcting at least one of the first setting time and the second setting time so that the second setting time becomes shorter than the first setting time. It is a thing.

[0009]

According to the present invention having such a configuration, at least one of the first set time and the second set time is changed by the set time changing means, whereby the second set time is set to the first set time. When it becomes longer than the time, at least one of the first set time and the second set time is automatically corrected so that the second set time becomes shorter than the first set time.

Therefore, the second time is always applied to the first set time.
The setting time of is shorter, so when the power saving control is continued when the signal is not received from the external device for the first setting time or longer, the print information held in the buffer is already printed out. And the buffer is empty.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to a laser printer having an electrophotographic printing process.

FIG. 1 shows the structure of a mechanical portion of a laser printer, and reference numeral 1 denotes a housing. The housing 1 is composed of an upper housing and a lower housing, and can be opened by rotating one end side of the upper housing upward with respect to the lower housing.

The casing 1 is provided with a photosensitive drum 2 at substantially the center thereof, and a motor 3 for driving the photosensitive drum 2 and various mechanical parts.

Around the photosensitive drum 2, a charging unit 4 including a charging charger in order in the rotation direction of the photosensitive drum 2, a developing device 5 including toner as a developer, a transfer unit 6 including a transfer charger, and a transfer paper. A charge removing charger 7 for removing the charge, a cleaning device 8 for cleaning the residual toner remaining after transfer, and a charge removing lamp 9 for removing the charge on the photosensitive drum 2 are arranged.

A laser scanner unit 10 is arranged above the photosensitive drum 2, and a laser beam from the laser scanner unit 10 is applied to the surface of the photosensitive drum 2 from between the charging section 4 and the developing device 5. It is designed to scan with.

The surface of the photosensitive drum 2 is made of a photoconductive material. During printing, the photosensitive drum 2 is rotated in the direction of the arrow in the drawing, the surface of the photosensitive drum 2 is uniformly charged by the charging unit 4, and then the surface of the photosensitive drum 2 is exposed by a laser beam from the laser scanner unit 10 and electrostatically based on print information. A latent image is formed. Then, the toner supplied from the developing device 5 is attached to the electrostatic latent image formed on the surface to form a toner image.

A paper feed cassette 11 is provided at one end of the housing 1.
Is provided, the transfer paper is sent out from the paper feed cassette 11 by the operation of the pickup roller 12 at the time of printing, and the transfer paper is conveyed to the position of the transfer section 6.

The transfer section 6 charges the transfer sheet and transfers the toner image formed on the photosensitive drum 2 from the surface of the photosensitive drum 2 to the transfer sheet by the electrostatic attraction, and the charge removing charger 7 transfers the transferred sheet. The transfer paper is designed to be neutralized.

A heat fixing device 13 including a heat roller and a pressure roller is provided on the other end side of the housing 1, and the transfer sheet from which the charge has been removed is heated and pressed by the heat fixing device 13 to be fixed. The paper is discharged to the outside by the paper discharge roller 14. Inside the casing 1, there are further provided a fan 15 for cooling the inside of the casing, a DC power source 16, an open detection switch 17 for detecting that the upper casing is opened, and the like.

FIG. 2 shows a circuit configuration. This laser printer is equipped with a one-chip microcomputer COM. The microcomputer COM includes a main microprocessor 21 that constitutes a main body of a control unit and controls printing operations, a ROM (read only memory) 22 that stores a control program for the microprocessor 21, and an external host computer. A RAM (ramdom access memory) 23 having a buffer for temporarily storing print information sent from the device, and an I / O port 24 for controlling input / output of data and signals to / from peripheral circuits described later are incorporated. There is. Then, the microprocessor 21
The ROM 22, the RAM 23, and the I / O port 24 are electrically connected to each other via a bus line 25.

The I / O port 24 is connected to the motor 3
Of signals from a motor drive circuit 26 for driving and controlling the laser scanner unit 10, the laser scanner unit 10, the charging unit 4, the transfer unit 6 and a charge removing charger 7 for supplying a high voltage, a toner empty sensor 28 and a toner full sensor 29. Toner sensor circuit 30 for input processing, operation panel 31 provided with various keys and indicators, paper sensor 32 for detecting transfer paper being conveyed, fan 1
5, an interface controller 33 and a heater controller 34 for controlling heat generation of the heater incorporated in the heat roller of the heat fixing device 13 are connected.

The open detection switch 17 is a DC power supply 16
From the motor drive circuit 26, the laser scanner unit 10, the high voltage power supply 27, and the fan 15 to the power supply line for supplying a voltage of 24 V, and when the upper housing of the housing 1 is opened, the power supply line is detected and detected. It is designed to be opened.

A well-known Centronics parallel interface 35 is connected to the interface controller 33, and the parallel interface 35 is connected to the interface controller 33.
A host computer 36, which is an external device, is connected to. The host computer 36 edits information input from a keyboard or read from a floppy disk into print information, and the parallel interface 3
5 to the interface controller 33.

As shown in FIG. 3, the operation panel 31 has a work switching means 41 and a power save (P
S) Mode switching means 42, timeout printing (PO) mode switching means 43, power save timer value input means 44
Each operation means of the time-out print timer value input means 45 is composed of various keys.

Here, the power saving mode means that when the signal reception from the host computer 36 does not continue for more than a first set time set in a power save timer 51 described later, the heat fixing device 13 is operated. In this mode, the heater incorporated in the heat roller is changed from a normal temperature control state to a low temperature control state to perform power saving control. The power save mode switching means 42 sets / cancels this power save mode. It is a means for switching alternately. The power save timer value input means 44 is means for setting time data corresponding to the first set time in the power save timer 51, and can set a time of 1 minute unit within a range of 1 minute to 60 minutes, for example. It has become.

It should be noted that instead of lowering the control temperature of the heater to perform power saving control, power supply to the heater may be completely stopped to perform power saving control. In addition, the power saving control may be performed on the other circuit parts simultaneously with the heater.

The time-out print mode is the RAM 23.
When the state in which the print information is stored in the buffer for more than the second set time set in the timeout print timer 52 to be described later continues, each unit is controlled based on the print information to perform printing, and the buffer is set to the empty state. The time-out print mode switching means 43 is a means for alternately setting / releasing the time-out print mode. Also, the timeout print timer value input means 4
Reference numeral 5 is a means for setting time data corresponding to the second set time in the time-out print timer 52, and is capable of setting a time in units of 1 second, for example.

The power save mode switching means 4
2, the timeout print mode switching means 43, the power save timer value input means 44 and the timeout print timer value input means 45 are executed in the setting work. Incidentally, the work switching means 41 is a means for switching between the setting work and the normal printing work.

Further, the operation panel 31 is
As shown in FIG. 3, the power save timer value display means 4
6. Each of the time-out print timer value display means 47 and the time-out print timer maximum value display means 48 is constituted by a display.

Here, the power save timer value display means 4
Reference numeral 6 indicates the first set time set in the power save timer 51 by the power save timer value input means 44. The timeout print timer value display means 47 displays the second set time set in the timeout print timer 52 by the timeout print timer value input means 45. The timeout print timer maximum value display means 48 displays the maximum value of the range of the second set time which can be set in the timeout print timer 52 by the timeout print timer value input means 45. In addition, these display means 46-4
In No. 8, the corresponding data may be displayed at least only when the setting job is selected.

The power save timer (PST) 51 and the timeout print timer (POT) 52 are formed in the RAM 23 as shown in FIG. RAM2
Reference numeral 3 denotes a buffer for storing print information, a maximum value memory (POTMAX) 53 for storing the maximum value of the second set time that can be set in the timeout print timer, and a save memory (for storing and holding time data. SM) 54, a flag memory 55 of a power save mode flag (PSMF) set during the setting period of the power save mode, a flag memory 56 of a timeout print mode flag (POMF) set during the setting period of the timeout print mode, the save A memory area such as a flag memory 57 of a save memory flag (SMF) set during the data save period is formed in the memory 54.

When the microprocessor 21 is powered on by turning on the power switch, as shown in FIG.
As the initialization process, the power save timer 51 has a first
Is set to an initial value T0, and the timeout print timer 52 is set to an initial value U0 as a second set time.
Set (U0 <T0). Also, the maximum value memory 53
To the initial value T0 set in the power save timer 51
Set a value that is 1 second shorter than. Further, each flag in each flag memory 55, 56, 57 is reset to "0". After that, each unit is controlled to execute the processing of the business selected by the business setting means 41.

Here, when the print job is selected by the job setting means 41, normal print job processing is executed. That is, when the print information is received from the host computer 36, the print information is temporarily stored in the buffer of the RAM 23 and then the print control is started.

In this printing control, the photosensitive drum 2 is rotated, and the charging unit 4, the laser scanner unit 10, the developing device 5, the transfer unit 6 and the charge eliminating lamp 9 are respectively operated, and the surface of the photosensitive drum 2 is buffered. The toner image is formed based on the print information of. Also, the pickup roller 1
2 is operated to feed the transfer paper from the paper feed cassette 11, the toner image is transferred to the transfer paper at the transfer unit 6, and the transfer paper on which the toner image is transferred is neutralized by the neutralization charger 7 and then heat-fixed. It is thermally fixed by heating and pressurizing in the device 13, and is discharged to the outside. In this way, printing on the transfer sheet based on the received print information is sequentially performed.

However, when a trouble such as paper shortage or paper jam occurs during the printing operation and the printing operation is temporarily stopped, print information is stored in the buffer. At this time, when the timeout print mode is set, that is, when the timeout print mode flag of the flag memory 56 is set, the microprocessor 21 stores the print information in the buffer for the timeout print timer 52. When the time set for is exceeded, the printing operation is automatically restarted after the failure recovery, and the printing information in the buffer is printed.

When the power save mode is set, that is, when the power save mode flag of the flag memory 55 is set, signal reception from the host computer 36 is set in the power save timer 51. It is determined whether or not the state of not exceeding the first set time continues. If it continues, power saving control is performed by changing the heater incorporated in the heat roller of the thermal fixing device 13 from the normal temperature control state to the low temperature control state.

On the other hand, when the setting work is selected by the work setting means 41, various setting work processes are executed according to the key input operation on the operation panel 31. Here, when the power save mode switching means 42 performs the power save mode switching operation, the processing shown in FIG. 6 is executed. That is, in ST61, the power save mode flag of the flag memory 55 is checked. And
If this flag is reset to "0", the setting of the power save mode is instructed, so the power mode flag is set to "1".

Next, at ST62, the timeout print mode flag of the flag memory 56 is checked. If this flag is reset to "0", the timeout print mode has not been set, and this process is terminated.

If the time-out print mode flag is set to "1" in ST62, the first set time set in the power save timer 51 and the time-out print timer 52 are set in ST63. The second set time is compared (set time comparison means). Then, if the second set time is shorter than the first set time, this processing is ended.

If the first set time and the second set time are equal to each other or the second set time is longer than the first set time in ST63, the timeout print timer 52 is set first. The previously set second set time is written and stored in the save memory 54. Next, a time shorter than the first set time in the power save timer 51 by 1 second is calculated,
The time-out print timer 52 is set as the second set time. That is, the second set time for the timeout print timer 52 is automatically corrected to a time shorter than the first set time in the power save timer 51 by one second from the time saved in the save memory 54 (automatic correction of set time). means).

Next, the maximum value memory 53 stores a time shorter than the first set time set in the timeout print timer 52 by 1 second. Then, the power save timer 51
The first set time of the operation time, the second set time of the time-out print timer 52, and the time stored in the maximum value memory 53, the display means 46, 47, 4 of the operation panel 31.
Display in 8 respectively. After that, if the save memory flag of the flag memory 57 is set to "1", this process ends.

On the other hand, when the power save mode flag is set to "1" in ST61, the power save mode setting is instructed to be canceled, so the power mode flag is reset to "0".

Next, at ST64, the timeout print mode flag of the flag memory 56 is checked. If this flag is reset to "0", the timeout print mode has not been set, and this process is terminated.

When the time-out print mode flag is set to "1" in ST64, the save memory flag of the flag memory 57 is checked in ST65. Then, if this flag is reset to "0", since the data is not saved in the save memory 54, this process ends.

At ST65, the save memory flag is "1".
If it is set to, the data saved in the save memory 54 is set in the timeout print timer 52 as the second set time. That is, the second set time saved in the save memory 54 by the previous set time correction means is returned to the timeout print timer 52.

Next, the timeout print timer 52
Then, the second set time set in the above is stored in the maximum value memory 53. Then, the second timer in the timeout print timer 52
The set time and the time stored in the maximum value memory 53 are displayed on the display means 47 and 48 of the operation panel 31, respectively. After that, if the save memory flag of the flag memory 57 is reset to "0", this process ends.

Further, when the time-out print mode switching means 42 performs the time-out print mode switching operation at the time of selecting the setting job, the processing shown in FIG. 7 is executed. That is, as ST71, the flag memory 56
Check the timeout print mode flag of. If the flag is reset to "0", the time-out print mode setting is instructed, so the time-out print mode flag is set to "1".

Next, in ST72, the power save mode flag of the flag memory 55 is checked. If this flag is reset to "0", the power save mode has not been set, so this processing ends.

When the power save mode flag is set to "1" in ST72, the first set time set in the power save timer 51 in ST73 and the timeout print timer 52 are set. The second set time is compared (set time comparison means). Then, if the second set time is shorter than the first set time, this processing is ended.

If the first set time and the second set time are equal or the second set time is longer than the first set time in ST73, the time-out print timer 52 is set first. The previously set second set time is written and stored in the save memory 54. Next, a time shorter than the first set time in the power save timer 51 by 1 second is calculated,
The time-out print timer 52 is set as the second set time (set time automatic correction means).

Then, the maximum value memory 53 stores a time shorter than the first set time set in the timeout print timer 52 by 1 second. Then, the power save timer 51
The first set time of the operation time, the second set time of the time-out print timer 52, and the time stored in the maximum value memory 53, the display means 46, 47, 4 of the operation panel 31.
Display in 8 respectively. After that, if the save memory flag of the flag memory 57 is set to "1", this process ends.

On the other hand, if the time-out print mode flag is set to "1" in ST71, the time-out print mode setting cancellation is instructed. Therefore, after resetting the time-out print mode flag to "0", This process ends.

When the time data Tx is input by the power save timer value input means 44 at the time of selecting the setting work, the power save timer 51 is instructed to change the first set time. Therefore, the processing shown in FIG. 8 is executed. That is, first, the first set time set for the power save timer 51 is changed to the input time data Tx. At this time, the first set time set in the power save timer 51 is displayed on the display means 46 of the operation panel 31.

Next, in ST81, the power save mode flag of the flag memory 55 is checked. If this flag is reset to "0", the power save mode has not been set, so this processing ends.

If the power save mode flag is set to "1" in ST81, the time-out print mode flag of the flag memory 56 is checked in ST82. If this flag is reset to "0", the timeout print mode has not been set, so this processing ends.

When the time-out print mode flag is set to "1" in ST82, the first set time set in the power save timer 51 and the time-out print timer 52 are set in ST83. The second set time is compared (set time comparison means).

When the second set time is shorter than the first set time, the save memory flag of the flag memory 57 is checked in ST84. Then, if this flag is reset to "0", since the data is not saved in the save memory 54, this process ends.

At ST84, the save memory flag is "1".
If it is set to ST85, the data saved in the save memory 54 in ST85, that is, the second set time saved in the save memory 54 by the previous set time correction means and the power save timer 51 are set. The first set time that is present is compared. Then, if the time saved in the save memory 54 is longer than the first set time set in the power save timer 51, this processing ends.

In ST85, the save memory 54 is stored for a time longer than the first set time set in the power save timer 51.
If the saved time is shorter, the time saved in the save memory 54 is set in the timeout print timer 52 as the second set time.

Next, the timeout print timer 52
Then, the second set time set in the above is stored in the maximum value memory 53. Then, the second timer in the timeout print timer 52
The set time and the time stored in the maximum value memory 53 are displayed on the display means 47 and 48 of the operation panel 31, respectively. After that, if the save memory flag of the flag memory 57 is reset to "0", this process ends.

In ST83, when the first set time and the second set time are equal to each other or the second set time is longer than the first set time, first, the timeout print timer 52 is set. The previously set second set time is written and stored in the save memory 54. Next, a time shorter than the first set time in the power save timer 51 by 1 second is calculated,
The time-out print timer 52 is set as the second set time (set time automatic correction means).

Next, the maximum value memory 53 stores a time shorter than the first set time set in the timeout print timer 52 by 1 second. Then, the power save timer 51
The first set time of the operation time, the second set time of the time-out print timer 52, and the time stored in the maximum value memory 53, the display means 46, 47, 4 of the operation panel 31.
Display in 8 respectively. After that, if the save memory flag of the flag memory 57 is set to "1", this process ends.

Further, when the time data Ux is input by the time-out print timer value input means 45 at the time of selecting the set work, the change of the second set time set in the time-out print timer 52 is instructed. So
The processing shown in FIG. 9 is executed. That is, it is determined whether or not the time data Ux input in ST91 is less than or equal to the maximum value of the setting range of the second set time stored in the maximum value memory 53. Then, when the input time data Ux is less than or equal to the maximum value, the second set time for the timeout print timer 52 is changed to the input time data Ux, and this process is ended.

If the time data Ux input in ST91 is larger than the maximum value, a buzzer sound or the like is used to notify that there is an input value error, the input time data Ux is cleared, and this processing ends. To do.

In the laser printer of this embodiment having the above-described structure, when the power is turned on by turning on the power switch, the power save timer 51 is set to the initial value T0 as the first set time, and the timeout print timer 5 is set.
An initial value U0 (U0 <T0) is set to 2 as the second set time. Further, a value shorter than the initial value T0 set in the power save timer 51 by 1 second is set in the maximum value memory 53. However, the power save mode and the timeout print mode are canceled.

Here, for example, when changing the first set time of the power save timer 51 to operate the power save mode, after selecting the set job by the job switching means of the operation panel 31, the power save timer value is set. The desired time data Tx is input by the input means 44. Further, the power save mode switching means 42 is switched. By doing so, the first set time of the power save timer 51 is changed from the initial value T0 to the input value Tx,
When the power save mode flag is set and the signal reception from the host computer 36 continues for the first set time Tx or longer, the heater incorporated in the heat roller of the heat fixing device 13 is in the normal temperature control state. Power saving control such as changing from the low temperature control state to the low temperature control state is performed.

In this state, when the time-out print mode is also to function, the time-out print mode switching means 43 is switched in the setting work. By doing so, the timeout print mode flag is set, and the timeout print mode functions.

However, since the first set time of the power save timer 51 is changed to be shorter, the second set time U0 set in the timeout print timer 52 is longer than the first set time Tx. In case of
The second set time for the timeout print timer 52 is automatically corrected from the initial value U0 to a time shorter than the first set time Tx by 1 second.

Therefore, when the time when the print information is stored in the buffer exceeds the time (Tx-1 second) set in the timeout print timer 52, the print operation is automatically restarted and the print information in the buffer is saved. Printing is performed. At this time, the first set in the power save timer 51
Since the setting time of is longer than the time when the time-out printing is performed, the problem that the power save mode is entered before the time-out printing is performed cannot occur.

Since the second set time U0 set in the timeout print timer 52 is longer than the first set time Tx of the power save timer 51, the second set time for the timeout print timer 52 is longer. When modified, the first set time U0 before modification is held in the save memory 54. Then, after that, for example, when the power save mode switching means 42 is switched to cancel the power save mode in the setting work, the time U0 saved in the save memory 54 is set as the second set time in the timeout print timer 52. It returns automatically.

Similarly, in the setting work, even when the power save timer value input means 44 changes the first set time for the power save timer 51 to be longer than the time U0 in the save memory 54, the save memory 54 still stores the same value in the save memory 54. The saved time U0 is automatically returned to the timeout print timer 52 as the second set time.

When the first set time for the power save timer 51 is changed again to be shorter than the time U0 in the save memory 54, the time is shortened by 1 second from the changed first set time. The second set time is automatically corrected.

The second of the timeout print timer 52
It is also possible to change the set time of. For example, now
An initial value T0 is set as the second set time, and it is assumed that the initial value T0 is changed to be larger than the initial value T0. In this case, in the setting work, the time data Ux after the change is input by the timeout print timer value input means 45. Then, it is determined whether the input time data Ux is less than or equal to the maximum value stored in the maximum value memory 53. If it is less than the maximum value, the input time data Ux is set in the timeout print timer 52. On the other hand, if a time longer than the maximum value is entered, an error will occur. Therefore, when the second set time is changed, a time larger than the first set time of the power save timer 51 will not be erroneously set.

As described above, the laser printer of this embodiment is
When the power save mode and the time-out print mode function at the same time, by changing the first set time for entering the power save mode, the second set time for time-out printing is longer than the first set time. If so, the second set time is automatically corrected so that the second set time is shorter than the first set time. In addition, the maximum value of the setting range of the second set time in which the time-out printing is performed is always regulated to be shorter than the first set time of entering the power save mode, and the time of the maximum value or more is set. I'm trying to ban it.

Therefore, the second set time in which the time-out printing is performed is always shorter than the first set time in the power save mode, so that the power saving control is started while the print information is held in the buffer. Can be reliably prevented. As a result, the time-out printing function can be effectively added to the conventional laser printer having the power save mode, and the practicality of the laser printer can be improved.

In the laser printer of this embodiment, the second set time in which the time-out printing is performed is shorter than the first set time in which the power save mode is entered.
When the set time is automatically corrected, the second set time before correction is stored and retained in the save memory 54. And
After that, when the power save mode is released or when the first set time of the power save timer 51 is changed to be longer than the time U0 in the save memory 54, the second set time is automatically stored in the save memory 54. I am trying to return to the time before the correction that was held. Therefore, it is not necessary to return the second set time in which the time-out printing is performed to a desired value, that is, the time before the automatic correction, and it is possible to remove the feeling of complication.

In the case where the second set time is corrected so that the second set time for time-out printing is shorter than the first set time for entering the power save mode, the second set time in the above embodiment is used. The set time is modified to be shorter than the first set time by 1 second, but the shortened time is not limited to 1 second and can be modified within a range not impairing the practicality. If the timeout print timer 52 can set the set time in units of 0.1 seconds, it may be shortened in units of 0.1 seconds.

Further, in the above embodiment, the maximum value of the second set time for the timeout print timer 52 is set.
If the second set time for the timeout print timer 52 is changed without defining this, the power save timer 5
When the changed second set time is longer than the first set time as compared with the first set time for 1, the time-out print timer 52 is automatically corrected to a time shorter than the first set time. It may be configured to set to.

In the above embodiment, the second set time for the time-out print timer 52 is set to be shorter than the first set time for the power save timer 51.
However, the first set time may be modified such that the first set time for the power save timer 51 is longer than the second set time for the timeout print timer 52.

Although the above-described embodiments have been described with respect to the application of the present invention to a laser printer, the present invention is not necessarily limited to this. Instead of the laser scanner unit 10, an EL (electroluminescence) element or an E element is used.
It can also be applied to a printer using a head array composed of LDs (light emitting diodes). In short, it can be applied to a printer which has an electrophotographic printing process and receives print information from an external device.

[0081]

As described above in detail, according to the present invention, when the signal reception from the external device continues for the first set time or longer, the power saving control means is provided, and the print information is secondly stored in the buffer. With a function that also prints this print information when it is held for more than the set time, it is possible to prevent the problem of entering the power saving control while holding the print information in the buffer, thus improving the practicality. The obtained electrophotographic printer can be provided.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.

FIG. 2 is a circuit block diagram of the same embodiment.

FIG. 3 is a functional block diagram of an operation panel in the embodiment.

FIG. 4 is a diagram showing a main memory area of a RAM according to the first embodiment.

FIG. 5 is a flowchart showing the main processing of the microprocessor in the embodiment.

FIG. 6 is a flowchart specifically showing a power save mode switching process of the setting job process shown in FIG.

FIG. 7 is a flowchart specifically showing timeout print mode switching processing in the setting job processing shown in FIG.

FIG. 8 is a flowchart specifically showing a power save timer value input process of the setting business process shown in FIG.

9 is a flowchart specifically showing a timeout print timer value input process of the setting business process shown in FIG.

[Explanation of symbols]

 2 ... Photosensitive drum 4 ... Charging part 5 ... Developing device 6 ... Transfer part 10 ... Laser scanner unit 13 ... Thermal fixing device 21 ... Microprocessor 31 ... Operation panel 33 ... Interface controller 34 ... Heater controller 35 ... Parallel interface 41 ... Business switching Means 42 ... Power save mode switching means 43 ... Timeout print mode switching means 44 ... Power save timer value input means 45 ... Timeout print timer value input means 51 ... Power save timer 52 ... Timeout print timer 53 ... Maximum value memory 54 ... Save memory

Claims (1)

[Claims] 1. A print information received from an external device through an interface is temporarily stored in a buffer, a photosensitive member is uniformly charged, and then an electrostatic latent image is formed by exposure based on the print information in the buffer. , A developer is attached to the electrostatic latent image for development, the developed image is transferred to a transfer paper, and the transfer paper is thermally fixed by a heat fixing device to perform printing. Means for performing power saving control when the state of not receiving the signal for more than the first set time continues, and means for printing this print information when the state of holding the print information in the buffer for the second set time or more continues In the electrophotographic printer having both, the setting time changing means for respectively changing the first setting time and the second setting time, and the first setting time or the first setting time by the setting time changing means. Setting time comparing means for determining whether or not the second setting time is longer than the first setting time by changing the setting time, and the second setting time is determined by the comparing means. If it is determined that the second set time is longer than the set time, at least one of the first set time and the second set time is corrected so that the second set time is shorter than the first set time. An electrophotographic printer, comprising: an automatic correction device for a set time.