JPH0667565A - Image forming device - Google Patents

Abstract

PURPOSE:To make the temperature of a fixing device at the time of standing by as low as possible by setting a control target temperature low for every printer language in an image forming device. CONSTITUTION:When a printer controller 200 receives the printer language from an external equipment 220, a CPU 202 generates dot data on a RAM 203. Simultaneously, an engine controller 250 changes the control target temperature of the fixing device 150 from the control target temperature at the time of standing by to that at the time of printing. The control target temperature at the time of standing by is set corresponding to the kind of the printer language in the device 150. For example, in the case the structure of the data of the printer language is complicated, processing time such as generating the dot data becomes comparatively long, so that the control target temperature at the time of standing by is set to a comparatively low value. Therefore, power consumption of the image forming device at the time of standing by is decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus such as a laser beam printer using an electrophotographic process, which has a heating type fixing device.

[0002]

2. Description of the Related Art Image forming devices such as laser beam printers are
The printer controller includes a printer controller that performs processing such as generation of dot data from input print data, and an engine controller that controls the engine based on the dot data. The engine also includes a sheet feeding device that feeds the sheet, an optical unit such as a laser, a transfer roller that transfers the toner to the sheet, and a fixing device that fixes the toner image formed on the sheet to the sheet. It is a thing. Further, the fixing device is configured to include a fixing roller having a heater therein and the like. In the conventional image forming apparatus, when the printing operation is not performed (at the time of standby), the temperature of the fixing device is lowered as compared with that at the time of printing operation for the reason of reducing power consumption. The temperature control of the fixing device in the conventional image forming apparatus is performed as shown in FIG. 4, for example. In this figure, the flowchart on the right side represents the operation in the printer controller, and the flowchart on the left side represents the operation in the engine controller.

First, after the printer controller receives print data (step S410), dot data is generated based on this print data. That is, print data edit processing is performed (step S411). Then, the printer controller transmits a print start signal to the engine controller (step S413), and thereafter receives the print data of the next page. On the other hand, in the engine controller, the temperature of the fixing roller remains at the standby control target temperature (for example, 1
The temperature is controlled to 60 ° C. (step S424). When the print start signal transmitted from the printer controller is received (YES in step S420), the print operation is started (step S421), and the temperature of the fixing roller is controlled to the print control target temperature until printing is completed. (Steps S422 and S423). When the sheet to which the toner is attached is conveyed to the fixing device, the temperature of the fixing device rises to the print control target temperature. In this way, after the printing operation is completed, the temperature of the fixing roller is controlled again to the standby control target temperature.

[0004]

In the above conventional image forming apparatus, after the print data editing process (dot data generation, etc.) is completed, the temperature of the fixing device is changed from the standby control target temperature to the printing time. Switching to the control target temperature. However, after the print data edit processing is completed, the time until the printing operation is performed is short.Therefore, if the standby control target temperature is set low, the temperature of the fixing roller when the sheet is conveyed to the fixing device The temperature control target temperature may not rise. That is, poor fixing such as low temperature offset may occur. Therefore, the standby temperature cannot be lowered, and the power consumption during standby cannot be sufficiently reduced.

[0005]

SUMMARY OF THE INVENTION Therefore, the present invention provides an image forming apparatus,
The purpose is to reduce the temperature of the fixing device during standby as much as possible.

[0006]

According to a first aspect of the present invention, there is provided an image forming apparatus, which comprises a receiving processing means for receiving and processing a printer language, and a fixing device whose temperature is controlled to a predetermined control target temperature. When the receiving processing means receives the printer language, the control means changes the control target temperature from the standby control target temperature to the printing control target temperature, and a setting means for setting the standby fixing temperature corresponding to the type of the printer language. , Is provided.

[0007]

In the image forming apparatus according to the first aspect of the present invention, when the reception processing means receives the printer language, the control means changes the control target temperature of the fixing device from the standby control target temperature to the printing control target temperature. To do. Then, the temperature of the fixing device rises toward the control target temperature during printing.
When the sheet reaches the fixing device, the temperature of the fixing device reaches the control target temperature during printing. Then, when the sheet to which the toner adheres passes through the fixing device, the toner is heated and fixed on the sheet.

When the data structure of the printer language received by the reception processing means is complicated, the processing time in the reception processing means becomes relatively long, so that it is possible to sufficiently secure the heating time of the fixing device. is there. Therefore, in such a case, even if the standby control target temperature is set to a relatively low value, the heating time becomes long, so the temperature of the fixing device when the sheet is conveyed to the fixing device is set to the printing control target temperature. Can be raised up to. In this way, by setting the standby control target temperature as low as possible for each printer language, it is possible to reduce the power consumption of the image forming apparatus during standby.

[0009]

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

As an embodiment of the image forming apparatus of the present invention, FIG.
A sectional view of the laser beam printer is shown in FIG. This laser beam printer has the following configuration.

Inside the main body cover 100, there are provided a paper feed tray 120 in which sheets are stored, an image forming cartridge 130 having a photosensitive drum 131, an optical unit 140, a fixing device 150, and the like. These are usually
It is called an engine.

A paper feed roller 122 is disposed near the paper feed tray 120, and the paper feed roller 122 has a function of conveying a sheet from the paper feed tray 120 to the image forming cartridge 130. The photosensitive drum 131 inside the detachable image forming cartridge 130 can rotate counterclockwise in the drawing, and a charging brush 135 is disposed near the photosensitive drum 131. This charging brush 135
Thus, the photosensitive drum 131 is charged to a predetermined potential. Further, the surface of the charged photosensitive drum 131 is irradiated with a laser beam from the optical unit 140 to form a latent electrostatic image. The optical unit 140 includes a semiconductor laser 141, a polygon mirror 142, and the like. The developing device 133 forms a toner image by attaching an insulating toner to the electrostatic latent image. Transfer roller 134
Has a function of transferring the toner image on the photosensitive drum 131 to a sheet. Further, a blade 13 that scrapes off the residual toner at a position where it contacts the photosensitive drum 131.
5 are provided. Above the photosensitive drum 131,
A fixing device 150 that fixes the toner on the sheet is provided.

The fixing device 150 comprises a fixing roller 151 having a heater formed of a halogen lamp therein, and a pressure roller 152 for pressing a sheet against the fixing roller 151. Further, above the fixing device 150, a transport roller 160 and a paper discharge roller 165 are provided. On the upper part of the main body cover 100, there is provided a paper discharge tray 102 for discharging the sheet conveyed through the conveyance roller 160 and the paper discharge roller 165. Also,
The main body cover 100 is provided with a door 101 that can be opened and closed. The door 101 is opened when, for example, replenishing the sheet to the sheet feeding tray 120. Body cover 1
An operation panel 103 is arranged on the front surface of 00. The operation panel 103 is configured to include a display unit made of liquid crystal, a feed switch, a mode selection switch, and the like. The operator operates the operation panel 103 to select the printer language to be used.

Although not shown in FIG. 1, an engine controller 250 for controlling an engine such as the image forming cartridge 130 and a printer controller 200 for generating dot data or the like based on print data are arranged in the main body cover 100. It is set up.

FIG. 2 is a block diagram of the printer controller 200 and the engine controller 250. In the printer controller 200, the I / F 201 receives print data from the external device 220 such as a personal computer. The type (printer language) of print data received by the I / F 201 varies depending on the type of the external device 220. The print data received by the I / F 201 is sent to the CPU via the data bus 206.
It is input to 202. The CPU 202 reads the font data corresponding to the print data from the font ROM 204 and generates dot data. The dot data is written in the RAM 203.

The CPU 202 outputs a video signal based on this dot data to the I / F 251 of the engine controller 250 via the I / F 205. In addition to the video signal, the printer controller 200 transmits to the engine controller 250 a print start signal indicating the start of printing, a mode signal indicating the type of printer language, and the like. On the contrary, the engine controller 250 sends horizontal and vertical synchronization signals to the printer controller 200.

Further, the printer controller 200 I
The operation panel 103 is connected to the / F 205. The operator uses this operation panel 1
By operating 03, the printer language corresponding to the external device 220 is selected.

In the engine controller 250, I
The video signal transmitted to the / F251 is the data bus 253.
Is input to the CPU 252 via. The CPU 252
The operation of the engine is controlled based on this video signal and the like. That is, a video signal is output to the optical unit 140 of the engine via the I / F 254, and the optical unit 130 modulates the laser beam according to this video signal. Further, the print operation of the engine is controlled by giving a control signal such as a print start signal to the engine.

From the I / F 254, the fixing device 150
The heater control signal is output to. The heater control signal is a signal for controlling the temperature of the heater that heats the fixing roller 151 of the fixing device 150. A temperature detection signal is output from the fixing device 150 to the I / F 254. This temperature detection signal is output from a temperature sensor provided on the fixing roller 151 and is a signal indicating the temperature of the fixing roller 151. The CPU 252 of the engine controller 250 gives a predetermined heater control signal to the fixing device 150 based on this temperature detection signal,
The temperature of the fixing roller 151 is controlled. In addition,
The control of the heater may be either on / off binary control, continuous value control using a PID parameter, or sample value control.

Next, the operation of the laser beam printer according to this embodiment will be described with reference to the flow chart shown in FIG.

In this figure, the flowchart on the right side shows the operation in the printer controller 200, and the flowchart on the left side shows the operation in the engine controller 250. First, the engine controller 20
0, the CPU 202 operates the operation panel 1
It is determined whether the printer language has been switched via 03 (step S301). When the printer language has been switched (YES in step S301), the printer controller 200 transmits the type of the switched printer language as a mode signal to the engine controller 250 (step S302).

Then, in the engine controller 250, since the determination result of step S350 is YES, the CPU 252 determines the control target temperature of the fixing device 150 in the standby state, that is, the standby control target in accordance with the type of the printer language. Change the temperature (step S35)
1). When a printer language having a complicated data structure of print data is selected, the time until the printer controller 200 generates dot data after receiving the print data becomes relatively long. For example, in a printer language such as Postscript, this time is approximately 10 seconds. On the other hand, when a printer language (PCPR201 etc.) having a relatively simple print data structure is selected,
The time required for the printer controller 200 to generate dot data after receiving print data is relatively short (for example, 2 seconds).

As described above, the time required to generate dot data differs depending on the type of printer language. That is, the time from the reception of print data to the conveyance of the sheet to the fixing device 150 differs depending on the type of printer language. Therefore, when a printer language having a complicated print data structure is selected, the time required to generate the dot data becomes long, and thus the heating time of the heater can be sufficiently secured. Therefore, when such a printer language is selected, low power consumption of the image forming apparatus can be realized by setting the standby control target temperature low.

When the engine controller 250 does not receive the mode signal because the printer language has not been switched (NO in step S350), the temperature of the fixing roller 151 is kept on standby without changing the standby control target temperature. Temperature control is performed so as to be equal to the hour control target temperature (step S352).

In the printer controller 200, when print data is sent from the external device 220 to the I / F 201, the CPU 202 sends a signal to the engine controller 250 to raise the temperature of the fixing roller 151 to the temperature for printing. (Step S304). When the engine controller 250 receives this signal (YES in step S353), the control target temperature of the fixing roller 151 is changed to a temperature suitable for fixing (control target temperature during printing). This print control target temperature is, for example, 20
It is about 0 ° C. Then, the engine controller 250
Controls the heat generation of the heater in the fixing roller 151 so that the temperature of the fixing roller 151 becomes equal to the control target temperature during printing (step S354). Therefore, the temperature of the fixing roller 151 starts to increase toward the print control target temperature.

At this time, in the printer controller 200, the CPU 202 reads the font data corresponding to the received print data from the font ROM 204 and generates dot data on the RAM 203. When the editing process such as dot data generation is completed (step S3)
05), the CPU 202 determines whether or not the engine is in a printable state (step S306). If the printer controller 200 determines that the engine is in a printable state (YES in step S306).
S), the printer controller 200 transmits a print start signal to the engine controller 250 (step S).
307). After that, the printer controller 200 waits for the print data of the next page to be transmitted.

When the engine controller 250 receives the print start signal (YES in step S355), the engine starts the print operation (step S35).
6). Then, the sheet feeding roller 122 conveys the sheet from the sheet feeding tray 120 to the image forming cartridge 130, and the toner image is transferred onto the sheet from the photosensitive drum 131 in the image forming cartridge 130. Then, this sheet is conveyed to the fixing device.

When the sheet is conveyed to the fixing device, the temperature of the fixing roller 151 has already reached the control target temperature during printing. Therefore, the toner on the sheet is fixed on the fixing roller 1.
It melts under the heat of 51 and settles on the sheet. The sheet on which the toner is fixed is ejected to the paper ejection tray 102 via the conveyance roller 160 and the paper ejection roller 165.
When the printing operation is completed in this way (YES in step S357), the process returns to step S350, and the engine controller 250 repeatedly executes the processes of steps S350 to 357.

Therefore, as described above, according to the image forming apparatus of this embodiment, the printer controller 200
Upon receiving the print data, the control target temperature of the fixing roller 151 is switched from the standby control target temperature to the print control target temperature. After that, the printer controller 200 generates dot data, and the sheet is fixed to the fixing device 1.
It is possible to secure a sufficient time until it is transported to 50. That is, the temperature of the fixing roller 151 can be raised to the print control target temperature within this time. Therefore, the standby control target temperature of the fixing roller 151 can be set low, and the power consumption of the laser beam printer during standby can be reduced.

In the laser beam printer according to this embodiment, the standby control target temperature is changed for each type of printer language. For example, in a printer language such as Postscript that requires a long time to generate dot data, the standby control target temperature is set sufficiently low (about 115 ° C.). Further, in a printer language for a personal computer, which can generate dot data in a short time, the standby control target temperature is set high (about 157 ° C.). In this way, by changing the standby control target temperature for each printer language, the standby control target temperature is set so that the temperature of the fixing roller 151 rises to the printing control target temperature immediately before the sheet reaches the fixing device 150. It can be set as low as possible.

By the way, if the standby control target temperature is set to a constant value regardless of the printer language as in the conventional image forming apparatus, when the sheet reaches the fixing device 150, the temperature of the fixing roller 151 is still high. However, since the temperature does not rise to the control target temperature during printing, problems such as improper fixing may occur. However, in the present embodiment, such a problem does not occur, and the standby control target temperature can be set as low as possible for each printer language. Therefore, the power consumption during standby can be further reduced.

In the present embodiment, the printer language is switched by using the operation panel 103, but it is also possible to switch the printer language by operating a dip switch or the like inside the laser beam printer.

[0033]

As described above, according to the present invention, in the image forming apparatus, by setting the standby control target temperature for each printer language as low as possible, the temperature of the fixing apparatus in the standby state can be set. Can be lowered. Further, since it is possible to stop the cooling fan and the like during standby, it is possible to reduce the noise generated from the image forming device.

[Brief description of drawings]

FIG. 1 is a sectional view of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram of a printer controller and an engine controller according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an operation of the image forming apparatus according to the embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of a conventional image forming apparatus.

[Explanation of symbols]

 150 fixing device 200 printer controller (reception processing means) 250 engine controller (control means, setting means)

Claims (1)

[Claims] 1. A reception processing means for receiving and processing a printer language, a fixing device whose temperature is controlled to a predetermined control target temperature, and a standby control target for the control target temperature when the reception processing means receives the printer language. An image forming apparatus comprising: a control unit that changes a temperature to a print control target temperature; and a setting unit that sets a standby fixing temperature in accordance with a printer language type.