JPH05257345A - Image forming device - Google Patents

Abstract

PURPOSE:To reduce driving load on each means provided for image formation and to start image formation with a short waiting time. CONSTITUTION:The device is constituted so that scanning drive control raising scanning W of light beam scanned by an optical unit 3 cycle a specified cycle, is started at a point when scanning start temperature lower than the specified temperature is reached while observing fixing temperature state of a fixing device 13 by an engine controller 25a when the fixing temperature of the fixing device 13 is risen by starting temperature control adjustment adjusting the fixing temperature of the fixing device 13 to a specified temperature according to the state of input of code data by a controller 26.

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 which transfers an image formed by scanning a light beam on a photoconductor to a recording medium to thermally fix the image.

[0002]

2. Description of the Related Art Conventionally, in this type of image forming apparatus, when code data of an image is input from an external device, the code data input by a video controller is analyzed, and an image to be printed is represented by a bit string video. The data is analyzed, video data in which the image to be printed is represented by a bit string is created, and stored in the bit map memory. During this time, the printer engine section waits for the print start command to be sent while the video controller section finishes developing the video data for one page while raising the temperature of the thermal fixing device to a temperature at which fixing can be performed. It is configured.

[0003]

However, in the above-mentioned conventional example, since the temperature of the heat fixing device is raised while the video controller develops the code data into the video data, the problems shown in the following (1) and (2) are encountered. There was a point.

(1) A process of raising a scanner motor for scanning a light beam, for example, a laser beam to a specified rotation, or applying a primary high voltage to uniformly charge the surface of the photosensitive drum and rotating the photosensitive drum for a specified time. If the processing time (hereinafter referred to as the pre-multi-rotation processing) takes longer than the temperature rise time of the fixing device, there is a problem that the effect of raising the temperature of the fixing device in advance disappears. ..

(2) If the scanner motor start-up process and the pre-multi-rotation process are directly performed at the same time as the temperature rise of the thermal fixing device, that is, after receiving the code data, the life of the scanner motor and the photosensitive drum is shortened. There was a problem that it became shorter.

The present invention has been made to solve the above-mentioned problems, and the scanning is started by causing the scanning means to start the scanning drive control in accordance with the fixing temperature rising state of the fixing means, or scanning is performed by the scanning means. Provided is an image forming apparatus capable of starting image formation in a short waiting time while reducing the driving load of each unit used for image formation by starting the fixing temperature control of the fixing unit according to the scanning cycle state of the light beam. The purpose is to

[0007]

In the image forming apparatus according to the present invention, there is provided first control means for starting temperature adjustment control for adjusting the fixing temperature of the fixing means to a constant temperature in accordance with the input state of the code data. While monitoring the fixing temperature state of the fixing unit, the temperature of which is raised by the first control unit, the scanning period of the light beam scanned by the scanning unit is raised to a constant period when the scanning start temperature lower than a predetermined temperature is reached. Second control means for starting scan drive control is provided.

Further, there is provided a third control means for starting the charging control of the charging means for uniformly charging the photosensitive member based on the scanning drive control completion state of the scanning means by the second control means.

Further, the first control means for starting the scan drive control for raising the scanning cycle of the light beam scanned by the scanning means to a constant cycle in accordance with the input state of the code data, and the first control means. While monitoring the scanning cycle change state of the light beam scanned from the driven scanning means, temperature adjustment control is performed to adjust the fixing temperature of the fixing means to a constant temperature when the fixing start-up cycle that is longer than the fixed cycle is reached. And a second control means for starting.

Further, there is provided a third control means for starting the charging control of the charging means for uniformly charging the photosensitive member based on the scanning drive control completion state of the scanning means by the first control means.

[0011]

In the first aspect of the invention, the first control means starts temperature adjustment control for adjusting the fixing temperature of the fixing means to a constant temperature according to the input state of the code data, and the fixing temperature of the fixing means rises. In doing so, the second control unit monitors the fixing temperature state of the fixing unit where the temperature rises, and the scanning cycle of the light beam scanned by the scanning unit is constant when the scanning start temperature lower than a predetermined temperature is reached. It is possible to start the scan drive control which is started in a cycle and start the latent image formation in the minimum waiting time.

Further, the third control means starts the charging control of the charging means for uniformly charging the photoconductor based on the scanning drive control completion state of the scanning means by the second control means, and charges the photoconductor. It is possible to reduce the drum driving load and the like.

In the second aspect of the invention, the first control means starts the scan drive control for raising the scanning cycle of the light beam scanned by the scanning means to a constant cycle in accordance with the input state of the code data, and performs the scanning. When the scanning period of the light beam scanned by the scanning means becomes shorter, the second control means monitors the scanning cycle change state of the light beam scanned by the scanning means, and the fixing period becomes longer than a fixed period. When the start-up cycle is reached, temperature adjustment control for adjusting the fixing temperature of the fixing unit to a constant temperature is started, and latent image formation can be started with a minimum waiting time.

Further, the third control means starts the charging control of the charging means for uniformly charging the photoconductor based on the completion state of the scanning drive control of the scanning means by the first control means, and charges the photoconductor. It is possible to reduce the accompanying drum driving load.

[0015]

【Example】

[First Embodiment] FIG. 1 is a sectional view for explaining the arrangement of an image forming apparatus according to the first embodiment of the present invention. In the figure, 1
Reference numeral 6 denotes a CPU, which receives coded image information (code data) from a host computer or the like via an interface 17 with an external device by executing a control program stored in the ROM 19. The received code data is input to the image processing unit 20, and the image processing unit 20 stores the code data in the RAM 21 and analyzes the code data. Reference numeral 18 is a RAM used as a register or the like. The ROM 22 stores font data corresponding to the value of the code data. The font data corresponding to the code data is read from the ROM 22, all the received code data is converted into video data consisting of dots, and the frame memory 23 To store. When one page of video data is stored in the frame memory 23, the CPU 1
6 is an engine unit 25 via the video interface 24.
The print command is sent to the engine section 25 and the video data stored in the frame memory 23 is sent to the engine section 25 in synchronization with the main / sub-scanning synchronization signal from the engine section 25. Two
Reference numeral 6 is a controller unit (controller),
It is composed of 4.

In the image forming apparatus thus constructed, the first control means (controller section 26) causes the fixing means (fixing device 1 which will be described later) according to the input state of the code data.
When the fixing temperature of 3) is started to start the temperature adjustment control for adjusting the fixing temperature to a constant temperature and the fixing temperature of the fixing device 13 rises, the second control means (engine controller 25a described later)
While the fixing temperature state of the fixing device 13 in which the temperature rises is monitored, the light scanned by the scanning means (the rotary polygon mirror rotatably driven by the scanner motor of the optical unit 3) when the scanning start temperature lower than the predetermined temperature is reached. It is possible to start scan drive control for raising the beam scanning cycle to a constant cycle, and start latent image formation in a minimum waiting time.

Further, the third control means (engine controller 25a in this embodiment) controls the charging of the charging means for uniformly charging the photosensitive member on the basis of the scanning drive control completion state of the scanning means by the second control means. By starting the operation, it is possible to reduce the load of driving the drum due to the charging of the photoconductor. In the present embodiment, the case where the functions of the first and second control means are fulfilled by the functional processing of the engine controller 25a is shown, but they may be configured by independent hardware.

FIG. 2 is a sectional view showing an example of the engine section 25 shown in FIG. 1. The same parts as those in FIG. 1 are designated by the same reference numerals.

In the figure, reference numeral 1 denotes a printer main body, which is a laser beam printer in this embodiment. Reference numeral 2 is a photosensitive drum for visualizing video data, and 3 is an optical unit, which modulates a laser beam by the video data sent through the video interface 24, and rotates the photosensitive drum 2 on the photosensitive drum 2 by a rotating polygon mirror. To scan. Reference numeral 4 is a folding mirror that reflects the laser light emitted from the optical unit (scanning unit) 3, and 5 is a charger, which uniformly charges the photosensitive drum 2. A developing device 6 develops the electrostatic latent image on the photosensitive drum 2 into a toner image. A transfer device 7 transfers the toner image on the photosensitive drum 2 to a recording medium.
A cleaner 8 collects the toner remaining on the photosensitive drum 2 after the transfer. A paper feed roller 10 is a paper cassette 9
Feed the paper stored in. A paper feed / conveyance roller 11 conveys the fed paper to a transfer position. A paper feed sensor 12 detects the presence or absence of fed paper. A fixing device 13 fixes the toner image transferred onto the sheet by heating and pressing. A paper discharge sensor 14 detects the presence or absence of the paper discharged from the fixing device 13. Reference numeral 15 is a paper discharge tray. 25a is an engine controller.

The printer preparation processing operation in the image forming apparatus according to the present invention will be described below with reference to FIGS. 3 and 4. For the sake of explanation, it becomes active when the signal is at "H" level.

FIG. 3 is a timing chart for explaining the first print preparation processing operation in the image forming apparatus according to the present invention.

FIG. 4 is a flow chart showing an example of the print processing procedure in the image forming apparatus according to the present invention.
It should be noted that (1) to (8) indicate each step.

The controller unit 26 is a host computer.
Wait until the image code data is received from an external device such as a printer (1), and when the code data is received (timing T1 shown in FIG. 3), the video interface is instructed to start the print preparation operation to the engine unit 25. A print preparation command is sent via 24 (timing T1, T2 shown in FIG. 3) (2). The image processing unit 20 develops the code data into video data and stores it in the frame memory 23 (3). Next, it is judged whether the development of the code data into the video data is completed for one page (4). If it is not completed for one page, the process returns to the step (3), and if it is completed for one page, the step (5 ), The print signal, which is a signal of the video interface 24, is set to the “H” level (timing T shown in FIG. 3 in order to instruct the engine unit 25 to start printing.
7). Next, the engine unit 25 recognizes that the print signal has become the “H” level, feeds the paper, and waits for the synchronization signal in the sub-scanning direction to be sent out via the video interface 24 (6 ), When the sub-scanning signal is transmitted, the print signal is set to the “L” level at timing T8 shown in FIG. 3 (7), and the engine is synchronized with the sub-scanning synchronization signal and the main-scanning synchronization signal transmitted from the engine unit 25. One page of video data is sent to the unit 25 (8), and when one page has been sent, the process returns to step (1).

FIG. 5 is a flowchart showing an example of a first print processing procedure by the engine unit 25 shown in FIG. Note that (1) to (17) indicate each step.

After the power is turned on, the engine unit 25 is fixed to the fixing unit 13.
In order to reduce power consumption and avoid excessive temperature rise,
The temperature is adjusted so that the standby temperature lower than the temperature required for fixing is maintained (1), and it is judged whether or not a print preparation command is sent from the controller 26 via the video interface 24 (2). If not, the process returns to step (1), and if it is sent, temperature control is started to raise the temperature of the fixing device 13 to the print temperature required for fixing (timing T2 shown in FIG. 3) (3). .. Next, it detects that the temperature of the fixing device 13 has reached the scanner startup temperature, and waits until the scanner startup temperature is reached (4). The scanner startup temperature is
It is set between the standby temperature and the print temperature, and the time from when the scanner motor starts driving upon detecting that the scanner startup temperature has been reached until the scanner motor reaches the specified rotation speed is set. The temperature is about the printing temperature.

Then, the driving of the scanner motor in the optical unit 3 to which the rotary polygon mirror is attached is started (timing T4 shown in FIG. 3) (5). Next, the laser APC is carried out while controlling the current supplied to the laser while monitoring the laser light amount to adjust the laser to the specified light amount (6). Then, the main scanning synchronization signal that determines the writing position of the image, which is the output of the optical sensor arranged outside the image area on the scanning line of the laser, is monitored to determine whether the scanning cycle has become constant.
(7) When the scanning cycle becomes constant, the photosensitive drum 2 is initialized. Therefore, the main motor is driven to rotate the photosensitive drum 2, and the primary charging high voltage is applied (timing T5 shown in FIG. 3) ( 8). Next, at least the time t ₂ seconds for the photosensitive drum 2 to rotate by one revolution is waited (9), and the photosensitive drum 2 is uniformly charged (timing T6 shown in FIG. 3).
Next, it is judged whether the temperature of the fixing device 13 has reached the print temperature (10). If the print temperature is reached, it is determined that the print preparation operation is completed, and the controller 2
Waiting until the print signal is sent from 6 (11), and when the print signal becomes the “H” level, it is assumed that all preparations for printing are completed, the paper feed roller 10 is driven, and the paper cassette 9 feeds the paper. Feed the (12). Next, it is determined whether the fed paper reaches the paper feed sensor 12 (1
3) When reaching the paper feed sensor 12, the sub-scanning synchronization signal is sent to the controller 26 via the video interface 24 (14). Then, a latent image for one page is formed on the photosensitive drum 2 based on the video data sent from the controller 26 (15), and after the latent image formation for one page is completed, a print command for the next page is sent. (16) whether or not the print signal is in the “L” level state, and if NO, returns to step (12) to perform the printing operation of the next page, and YES
If so, the paper on which the latent image is developed and transferred passes through the fixing device 13,
The discharge sensor 14 detects that the paper has been discharged to the outside of the machine, and stops the scanner motor and the main motor (17), and the step (1)
Return to.

As described above, when the code data is input to the printer, the temperature of the fixing device 13 is raised to the print temperature, and the temperature of the fixing device 13 is set to a predetermined temperature in consideration of the rise time of the scanner motor. Since the scanner motor is started after the fact that the printing is started is detected, the processing time after receiving the print command can be shortened and the time until the first sheet is printed out can be shortened.

In the above embodiment, after the temperature of the fixing device 13 reaches the printing temperature, the temperature of the fixing device 13 is continuously maintained at the printing temperature until the print signal becomes "H" level. As described above, as shown in the flow chart of FIG. 6, when the print signal is sent from the controller 26 for a certain period, that is, does not become the “H” level, the standby temperature lower than the temperature required for fixing once is maintained. By switching to temperature control,
An excessive temperature rise of the fixing device 13 and unnecessary rotation of the scanner motor may be stopped.

FIG. 6 is a flowchart showing another example of the first print processing procedure by the engine unit 25 shown in FIG. The same processes as those in the flowchart of FIG. 5 indicate the same step numbers, and common processes are omitted. Further, (21) to (32) indicate each step.

When the temperature of the fixing device 13 reaches the print temperature in step (10) shown in FIG. 5, the engine section 25 sets a timer for counting up for 1 minute (21). Next, it is judged whether or not the print start command is sent from the controller 26 (22), and if NO, it is judged whether or not the timer set in step (1) has counted up (2
3) If NO, the process returns to step (22), and if YES, the temperature of the fixing device 13 is returned to the standby temperature in order to prevent excessive temperature rise of the fixing device 13 and unnecessary rotation of the scanner motor.
Stop the scanner motor and main motor (24). Next, it is judged that the controller 26 sends a print start command (25). When the print start command (print signal is at "H" level) is sent, the process returns to step (3) shown in FIG. After the fixing device 13 is heated to the printing temperature and the scanner motor is started to perform the print preparation operation, the printing operation is performed.

In the above embodiment, the fixing device 13 is kept at a constant printing temperature (for example, 1) in accordance with the input state of the code data.
80 ° C.) and the temperature adjustment control for maintaining the same is performed first, and when the temperature is raised to a temperature lower than the print temperature, the scanning unit 3 is activated in parallel, so that the latent image is formed with the minimum waiting time. Although the case where it is possible to start the formation has been described, as shown in the second embodiment below, the scan unit 3 is started up in advance in accordance with the input state of the code data, and the predetermined scan cycle is started. When it reaches the fixing device 13, the fixing device 13 is set to a constant printing temperature (for example, 18
The temperature adjustment control for raising and maintaining the temperature may be performed in parallel, and the same effect can be expected. [Second Embodiment] In this embodiment, the first control means (CPU 16) performs scan drive control for raising the scanning cycle of the light beam scanned by the scanning means to a constant cycle in accordance with the input state of code data. When the scanning cycle of the light beam scanned by the scanning unit (scanning unit 3) starts to decrease, the second control unit (engine controller 25a) scans the light beam scanned by the scanning unit 3 While monitoring the cycle change state, temperature adjustment control for adjusting the fixing temperature of the fixing device 13 to a constant temperature is started when the fixing start-up cycle, which is longer than the constant cycle, is reached, and latent image formation is performed with a minimum waiting time. Allows you to get started.

Further, the third control means (engine controller 25a in this embodiment) controls the charging of the charging means for uniformly charging the photoconductor on the basis of the scanning drive control completion state of the scanning means by the first control means. By starting the process, it is possible to reduce the load of driving the drum due to the charging of the photoconductor.

The second print processing operation in the image forming apparatus according to the present invention will be described below with reference to the timing chart shown in FIG. 7 and the flowchart shown in FIG.

FIG. 7 is a timing chart for explaining the second print preparation processing operation of the image forming apparatus showing the second embodiment of the present invention.

FIG. 8 is a flow chart showing an example of the second print processing procedure by the engine unit 25 shown in FIG. Note that (1) to (17) indicate each step.

After the power is turned on, the engine unit 25 is fixed to the fixing unit 13.
In order to reduce power consumption and avoid excessive temperature rise,
The temperature is adjusted so that the standby temperature lower than the temperature required for fixing is maintained (1), and it is judged whether or not a print preparation command is sent from the controller 26 via the video interface 24 (2). If not, the process returns to step (1), and if it is sent out, the driving of the scanner motor in which the rotary polygon mirror in the optical unit 3 is mounted on the axis is started (timing T2 shown in FIG. 7).
(3). Next, the number of rotations of the scanner motor is judged based on the tack output from the scanner motor (4). For example, when a four-cycle tack signal is output per one rotation of the scanner motor (scanner motor rotation number ≧ N), N per second When a tack signal is input for / 4 cycles or more, proceed to step (5) and thereafter. It should be noted that the scanner rotation speed N is determined by combining the time t ₁ required for the scanner motor to reach the specified rotation speed from the rotation speed N and the pre-multi-rotation time t ₂ described later, so that the fixing device 13 rises from the standby temperature to the printing temperature. It is adjusted to be equal to the warming time t ₃ .

Next, temperature adjustment is started (timing T4 shown in FIG. 7) so as to raise the temperature of the fixing device 13 to the print temperature required for fixing (5). Next, wait until the scanner motor reaches the specified number of revolutions (6) .When the scanner motor reaches the specified number of revolutions, the current given to the laser is controlled while monitoring the light amount of the laser so that the laser reaches the specified light amount. Perform laser APC for adjustment (7). When the amount of laser light reaches the specified amount of light, the scanner motor is rotating as specified.Therefore, the main scanning synchronization signal that determines the image writing position, which is the output of the optical sensor placed outside the image area on the laser scanning line, also has the specified period. Become. Next, in order to initialize the photosensitive drum 2, the main motor is driven and the photosensitive drum 2
While rotating, the primary charging high voltage is applied (timing T5 shown in FIG. 7) (8). Next, at least the time t ₂ seconds for the photosensitive drum 2 to rotate by one revolution is waited (9) to uniformly charge the photosensitive drum 2 (timing T shown in FIG. 7).
6). Next, it is determined whether the temperature of the fixing device 13 has reached the print temperature (10). If the print temperature is reached, it is determined that the print preparation operation has been completed, and the controller 26 sends a print signal. Wait (1
1) When the print signal becomes "H" level, it is determined that the preparation for printing is completed, and the paper feed roller 10 is driven to feed the paper from the paper cassette 9 (12). Then
It is judged whether the fed paper reaches the paper feed sensor 12 (13), and when it reaches the paper feed sensor 12, a sub-scanning synchronization signal is sent to the controller 26 via the video interface 24 (14). Then, a latent image for one page is formed on the photosensitive drum 2 based on the video data sent from the controller unit (15), and after the latent image formation for one page is completed, a print command for the next page is sent. The print signal is in the “L” level state (16), N
If it is O, the process returns to step (12) to perform the printing operation for the next page, and if it is YES, the paper on which the latent image has been developed and transferred is the fixing device 1.
After passing 3, the paper discharge sensor 14 detects that the paper has been discharged to the outside of the machine, stops the scanner motor and the main motor (17), and returns to step (1).

As described above, the number of rotations of the scanner motor is adjusted in consideration of the time when the scanner motor is started at the time when the code data is input to the printer and the fixing device 13 is heated from the standby temperature to the printing temperature. It is possible to shorten the processing time after receiving a print command after that, because the temperature rise to the print temperature of the fixing device 13 is started by detecting that the rotation speed reaches the predetermined rotation speed before reaching the specified rotation speed. it can.

In the above embodiment, after the temperature of the fixing device 13 reaches the printing temperature, the temperature of the fixing device 13 is continuously maintained at the printing temperature until the print signal becomes "H" level. As described above, as shown in the flow chart of FIG. 6, when the print signal is sent from the controller 26 for a certain period, that is, does not become the “H” level, the standby temperature lower than the temperature required for fixing once is maintained. By switching to temperature control,
An excessive temperature rise of the fixing device 13 and unnecessary rotation of the scanner motor may be stopped. As a result, the fixing device 13
When a print command is not sent from the controller 26 for a certain period of time after the temperature reaches the print temperature, the controller 26 once returns to the standby state, so that excessive temperature rise of the fixing device 13 and unnecessary rotation of the scanner motor are eliminated. You can

[0040]

As described above, according to the present invention, the first control means for starting the temperature adjustment control for adjusting the fixing temperature of the fixing means to a constant temperature according to the input state of the code data,
A scan in which the scanning cycle of the light beam scanned by the scanning means is raised to a constant cycle when the scanning temperature reaches a scanning start temperature lower than a predetermined temperature while monitoring the fixing temperature state of the fixing means which rises in temperature by the first control means. Since the second control means for starting the drive control is provided, the latent image formation can be started in the minimum waiting time without forcing the scanning means to uselessly drive, and the first print time can be greatly shortened. ..

Further, the third control means for starting the charging control of the charging means for uniformly charging the photoconductor on the basis of the completion state of the scanning drive control of the scanning means by the second control means is provided. It is possible to prolong the service life of the photoconductor peripheral device that constitutes the image forming means and reduce the running cost without forcibly driving the photoconductor peripheral device that constitutes the means.

Further, the first control means for starting the scan drive control for raising the scanning cycle of the light beam scanned by the scanning means to a constant cycle according to the input state of the code data, and the first control means. While monitoring the scanning cycle change state of the light beam scanned from the driven scanning means, temperature adjustment control is performed to adjust the fixing temperature of the fixing means to a constant temperature when the fixing start-up cycle that is longer than the fixed cycle is reached. Since the second control means for starting is provided, the timing at which the scanning means has a constant cycle and the timing at which the fixing temperature of the fixing device becomes the print canopy temperature can be synchronized, and latent image formation can be performed with a minimum waiting time. Can start
First print time can be greatly reduced.

Further, the third control means for starting the charging control of the charging means for uniformly charging the photosensitive member on the basis of the completion state of the scanning drive control of the scanning means by the first control means is provided. It is possible to prolong the service life of the photoconductor peripheral device that constitutes the image forming means and reduce the running cost without forcibly driving the photoconductor peripheral device that constitutes the means.

Therefore, since the fixing unit and the scanning unit can be driven at appropriate timings with a small driving load, the waiting time of both at the start of the first printing can be shortened and the first printing time can be further shortened. And so on.

[Brief description of drawings]

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

FIG. 2 is a cross-sectional configuration diagram showing an example of an engine unit shown in FIG.

FIG. 3 is a timing chart illustrating a first print preparation processing operation in the image forming apparatus according to the present invention.

FIG. 4 is a flowchart showing an example of a print processing procedure in the image forming apparatus according to the present invention.

5 is a flowchart showing an example of a first print processing procedure by the engine unit shown in FIG.

FIG. 6 is a flowchart showing another example of the first print processing procedure by the engine unit shown in FIG.

FIG. 7 is a second image forming apparatus according to the second embodiment of the present invention.
8 is a timing chart for explaining the print preparation processing operation of FIG.

8 is a flowchart showing an example of a second print processing procedure by the engine unit shown in FIG.

[Explanation of symbols]

 1 Printer Main Body 3 Optical Unit 13 Fixing Device 16 CPU 25 Engine Section 26 Controller Section

Continuation of front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location G03G 15/20 109 (72) Inventor Hideki Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (4)

[Claims] 1. A scanning means for scanning and imaging a light beam, which is modulated and emitted based on inputted code data, on a photoconductor at a constant cycle, and a light beam which is scanned by the scanning means onto the photoconductor. An image forming apparatus comprising: an image forming unit that develops a formed latent image and transfers the latent image to a recording medium; and a fixing unit that heat-fixes the image transferred to the recording medium by the image forming unit at a constant temperature. First control means for starting temperature adjustment control for adjusting the fixing temperature of the fixing means to a constant temperature according to the input state of the code data, and fixing of the fixing means whose temperature is raised by the first control means. Scanning drive control for raising the scanning cycle of the light beam scanned by the scanning unit to the constant cycle when the scanning start temperature lower than a predetermined temperature is reached while monitoring the temperature state. An image forming apparatus comprising: a second control unit for starting the operation. 2. A third control means for starting the charging control of the charging means for uniformly charging the photosensitive member based on the scanning drive control completion state of the scanning means by the second control means. The image forming apparatus according to claim 1. 3. A scanning means for scanning and forming an image of a light beam, which is modulated and emitted on the basis of inputted code data, on a photoconductor by a rotary polygon mirror at a constant cycle, and a light beam scanned by the scanning means. An image forming means for developing the latent image formed on the photoconductor by the above and transferring it to a recording medium, and a fixing means for fixing the image transferred to the recording medium by the image forming means by heat and pressure at a constant temperature. In the image forming apparatus, first control means for starting scan drive control for raising the scanning cycle of the light beam scanned by the scanning means to a constant cycle in accordance with the input state of the code data, and the first control means. While observing the changing state of the scanning period of the light beam scanned by the scanning unit driven by the control unit, before the time when the fixing start-up period becomes longer than the fixed period is reached. An image forming apparatus comprising: a second control unit that starts temperature adjustment control for adjusting the fixing temperature of the fixing unit to a constant temperature. 4. A third control means for starting the charging control of the charging means for uniformly charging the photosensitive member based on the scanning drive control completion state of the scanning means by the first control means. The image forming apparatus according to claim 1.