JP2004012509A - Image forming apparatus and image forming preparation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of accurately discriminating the completion of exposure preparation without preliminarily rotating a polygon motor, and an image forming preparation method. <P>SOLUTION: The exposure preparing operation of an exposure device is started (S505), the elapsed time of the started exposure preparing operation is measured, and the completion of the exposure preparation is determined when the measured elapsed time T1 coincides with exposure preparation completion scheduled time Tp stored in a storage means in advance (S512). <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus such as a printer and a copying machine, and more particularly to realizing both a stable first copy time and a long life of the image forming apparatus by accurately predicting a rise time of a polygon motor and the like. It is about.
[0002]
[Prior art]
2. Description of the Related Art In recent years, a copying machine as shown in FIG. 1 is generally used as an electrophotographic image forming apparatus. A conventional image forming apparatus will be described with reference to FIG. Although not described in detail, 1R is a document reading unit for performing a document copying operation. Next, the image output unit 1P is roughly divided into an image forming unit 10 (four stations a, b, c, and d are arranged side by side and have the same configuration), a sheet feeding unit 20, and an intermediate transfer unit. 30, a fixing unit 40 and a control unit (not shown).
[0003]
Further, individual units will be described in detail. The image forming section 10 has the following configuration. Photosensitive drums 11a, 11b, 11c, and 11d as image carriers are pivotally supported at their centers, and are driven to rotate in the direction of arrows. Primary chargers 12a, 12b, 12c, and 12d, optical systems 13a, 13b, 13c, and 13d, and developing devices 14a, 14b, 14c, and 14d are arranged in the rotational direction of the photosensitive drums 11a to 11d so as to face the outer peripheral surfaces thereof. I have. In the primary chargers 12a to 12d, charges of a uniform charge amount are given to the surfaces of the photosensitive drums 11a to 11d. Next, the optical systems 13a to 13d expose the photosensitive drums 11a to 11d with light beams such as laser beams modulated according to the recording image signals, thereby forming electrostatic latent images thereon. Further, the electrostatic latent images are visualized by developing devices 14a to 14d each storing a developer (toner) of four colors such as yellow, cyan, magenta, and black. On the downstream side of the image transfer areas Ta, Tb, Tc, Td for transferring the visualized visual image to the intermediate transfer belt, the photosensitive drums 11a to 11d are not transferred to the transfer material by the cleaning devices 15a, 15b, 15c, 15d. The toner remaining on 11d is scraped off to clean the drum surface. According to the process described above, image formation using each toner is sequentially performed.
[0004]
The paper feeding unit 20 includes cassettes 21a and 12b and a manual tray 27 for storing the recording material P, pickup rollers 22a, 22b and 26 for feeding the recording material P one by one from the cassette or from the manual tray, and each pickup roller. A sheet feeding roller pair 23 and a sheet feeding guide 24 for conveying the recording material P sent out from 22a, 22b and 26 to the registration rollers, and the recording material P is transferred to the secondary transfer area in accordance with the image forming timing of the image forming unit. It consists of registration rollers 25a and 25b for sending out to Te.
[0005]
The intermediate transfer unit 30 will be described in detail. The intermediate transfer belt 31 (for example, PET (polyethylene terephthalate), PVdF (polyvinylidene fluoride), or the like is used as the material) includes a driving roller 32 that transmits drive to the intermediate transfer belt 31, and biasing of a spring (not shown). Thus, the intermediate transfer belt 31 is wound around a tension roller 33 that applies an appropriate tension to the intermediate transfer belt 31 and a driven roller 34 that faces the secondary transfer area Te with the belt interposed therebetween. Among these, a primary transfer plane A is formed between the drive roller 32 and the tension roller 33. The drive roller 32 has a surface of a metal roller coated with rubber (urethane or chloroprene) having a thickness of several mm to prevent slippage with the belt. The drive roller 32 is driven to rotate by a pulse motor (not shown). Primary transfer blades 35a to 35d are arranged behind the intermediate transfer belt 31 in primary transfer areas Ta to Td where the respective photosensitive drums 11a to 11d and the intermediate transfer belt 31 face each other. A secondary transfer roller 36 is arranged to face the driven roller 34, and forms a secondary transfer area Te by nip with the intermediate transfer belt 31. The secondary transfer roller 36 is pressed with an appropriate pressure against the intermediate transfer belt. A cleaning device 50 for cleaning the image forming surface of the intermediate transfer belt 31 is disposed on the intermediate transfer belt 31 and downstream of the secondary transfer region Te. The cleaning device 50 includes a cleaner blade 51 (made of a material). , Polyurethane rubber, etc.) and a waste toner box 52 for storing waste toner.
[0006]
The fixing unit 40 includes a fixing roller 41a having a heat source such as a halogen heater therein, a roller 41b pressed by the roller (the roller may also have a heat source), and a transfer material to a nip portion of the roller pair. A guide 43 for guiding P, an inner discharge roller 44 and an outer discharge roller 45 for further guiding the transfer material P discharged from the roller pair to the outside of the apparatus.
[0007]
The control unit includes a control board 70 for controlling the operation of the mechanism in each unit, a motor drive board (not shown), and the like.
[0008]
Next, an explanation will be given in accordance with the operation of the apparatus.
[0009]
When the image forming operation start signal is issued, first, the transfer material P is sent out one by one from the cassette 21a by the pickup roller 22a. Then, the transfer material P is guided between the paper feed guides 24 by the paper feed roller pair 23 and is conveyed to the registration rollers 25a and 25b. At this time, the registration rollers 25a and 25b are stopped, and the leading end of the paper strikes the nip. Thereafter, the registration rollers 25a and 25b start rotating at the timing when the image forming unit starts forming an image. The rotation timing is set so that the transfer material P and the toner image primarily transferred from the image forming unit onto the intermediate transfer belt 31 just coincide in the secondary transfer area Te.
[0010]
On the other hand, in the image forming section, when the image forming operation start signal is issued, a high voltage is applied to the toner image formed on the photosensitive drum 11d at the most upstream in the rotation direction of the intermediate transfer belt 31 by the above-described process. The primary transfer is performed on the intermediate transfer belt 31 in the primary transfer region Td by the primary transfer charger 35d. The primary-transferred toner image is transported to the next primary transfer area Tc. In this case, the image formation is performed with a delay of the time during which the toner image is conveyed between the respective image forming sections, and the next toner image is transferred with the registration on the previous image. Hereinafter, the same steps are repeated, and the toner images of four colors are primarily transferred on the intermediate transfer belt 31 after all.
[0011]
Thereafter, when the recording material P enters the secondary transfer area Te and comes into contact with the intermediate transfer belt 31, a high voltage is applied to the secondary transfer roller 36 in accordance with the passage timing of the recording material P. Then, the four color toner images formed on the intermediate transfer belt 31 by the above-described process are transferred onto the surface of the recording material P. Thereafter, the recording material P is accurately guided to the fixing roller nip by the conveyance guide 43. The toner image is fixed on the surface of the recording material by the heat of the roller pair 41a and 41b and the pressure of the nip. Thereafter, the recording material is conveyed by the inner and outer discharge rollers 44 and 45, and the recording material is discharged outside the apparatus.
[0012]
In such an image forming apparatus, preparation for rotation of the photosensitive drums (11a, 11b, 11c, 11d), preparation for exposure start of the optical system (13a, 13b, 13c, 13d), and development for the image forming section are usually performed. When all the preparations for the development start (14a, 14b, 14c, 14d) are completed, the image forming operation becomes possible.
[0013]
However, in recent copiers, it has been a major issue to shorten the time until the first copy is discharged, that is, the so-called first copy time, while realizing high productivity. Control that is performed in parallel and minimizes the preparation time until the start of the image forming operation is becoming common. For example, in the example of FIG. 1, the preparation for the exposure start of the optical system (13a, 13b, 13c, 13d) corresponds to the completion of the startup of the polygon motor, and it takes the longest time among the three preparation operations. Next, the preparation for starting the development of the developing devices (14a, 14b, 14c, 14d) corresponds to the rise of the image forming high voltage (also referred to as the developing high voltage) applied to the photosensitive drums (11a, 11b, 11c, 11d). However, it cannot start unless the preparation for rotation of the photosensitive drums (11a, 11b, 11c, 11d) is completed.
[0014]
Therefore, first, the start of the photosensitive drums (11a, 11b, 11c, 11d) and the start of the start of the polygon motor are performed in parallel, and after the photosensitive drum is started, control for starting the image forming high voltage may be performed. . In addition, if the state in which the image forming high voltage is started is continued for a long time, the life of the photosensitive drum is greatly reduced. Therefore, when the image forming high voltage is started, the polygon motor is preliminarily started in advance. Accordingly, it has been proposed to measure the time required for starting up the polygon motor and perform control to match the start-up timing of the image forming high voltage with the start-up completion timing of the polygon motor.
[0015]
[Problems to be solved by the invention]
However, in the above-described control, since the rising time of the polygon motor has a great effect on the temperature rise in the image forming apparatus, it is necessary to determine the operation preparation time of the polygon motor immediately before the image forming operation. It is necessary to frequently start the polygon motor, and there is a problem that the life of the polygon motor is shortened. Conversely, if the frequency of starting the polygon motor is reduced to know the operation preparation time, a difference from the rising time of the polygon motor at the time of the image forming operation occurs. Also, when the rise time of the polygon motor during image formation took a long time, the rise control of the polygon motor was completed before the polygon motor shifted to the steady rotation, and the polygon motor did not reach the steady rotation within a certain time Therefore, there is a problem that an error occurs.
[0016]
Further, unnecessarily increasing the predicted rise time of the polygon motor is directly related to the longer first copy time, and thus it is difficult to determine the predicted rise time of the polygon motor.
[0017]
The present invention has been made under such circumstances, and provides an image forming apparatus and an image forming preparation method capable of obtaining an accurate determination of completion of exposure preparation without preliminary rotation of a polygon motor. The purpose is.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, the image forming apparatus is configured as in the following (1) to (18), and the image forming method is configured as in the following (20) to (22).
[0019]
(1) An exposure device, and an image forming device that forms a toner image based on the latent image formed by the exposure device, and forms an image on the transfer material by fixing the toner image on the transfer material. In an image forming apparatus for printing,
Storage means for storing an expected exposure preparation completion time required from when the exposure apparatus starts the exposure preparation operation to when the exposure preparation operation is completed, and an elapsed time elapsed since the exposure apparatus started the exposure preparation operation. An image forming apparatus comprising: a measuring means for measuring; and a judging means for judging completion of exposure preparation when the elapsed time measured by the measuring means coincides with the expected exposure completion time stored in the storage means.
[0020]
(2) In the image forming apparatus according to (1), the elapsed time measured by the measuring unit is a time obtained by subtracting a start-up time of an image forming high voltage from a scheduled exposure preparation completion time stored in the storage unit. An image forming apparatus, comprising: means for starting the rise of the image forming high voltage when the image forming high voltage is matched, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation.
[0021]
(3) The image forming apparatus according to (1) or (2), wherein the exposing device includes a polygon motor and a laser exposing unit.
[0022]
(4) In the image forming apparatus according to (1) or (2), the image forming apparatus includes a high-voltage unit that generates the image forming high voltage, a developing unit, and a toner supply unit.
[0023]
(5) The image forming apparatus according to (1) or (2), wherein the exposure device is configured by a plurality of sets.
[0024]
(6) In the image forming apparatus according to (1) or (2), the image forming apparatus is configured by a plurality of sets.
[0025]
(7) In the image forming apparatus according to (1) or (2), the time required for the exposure device to complete the preparation for exposure is longer than the time required for the image forming device to complete the preparation for image formation. Forming equipment.
[0026]
(8) In the image forming apparatus according to (1) or (2), the storage unit has an exposure preparation completion time table storing a plurality of exposure preparation completion times, and the exposure device Based on the temperature and / or humidity in the image forming apparatus immediately before starting the preparation operation, one of the scheduled exposure preparation completion times in the scheduled exposure preparation completion time table is selected to determine the required exposure preparation completion time and Image forming apparatus.
[0027]
(9) In the image forming apparatus according to (1) or (2), the storage unit has an exposure preparation completion time table that stores a plurality of exposure preparation completion times, and the exposure apparatus performs exposure. An image forming apparatus which selects one of the plurality of expected exposure preparation completion times according to an image forming mode at the time of starting a preparation operation and sets the required exposure preparation completion time as a required exposure preparation completion time.
[0028]
(10) An exposure device, and an image forming device that forms a toner image based on the latent image formed by the exposure device, and fixes the toner image on the transfer material to form an image on the transfer material. In an image forming apparatus for printing,
Storage means for storing a scheduled exposure preparation completion time from when the exposure apparatus starts the exposure preparation operation to when the exposure preparation operation is completed, and measurement means for measuring an elapsed time since the exposure apparatus started operation Detection means for detecting the completion of operation preparation of the exposure apparatus; and when the elapsed time measured by the measurement means has elapsed by the expected exposure preparation completion time stored in the storage means, the detection means detects the exposure apparatus. If the completion of the operation preparation is detected, the completion of the exposure preparation is determined at the elapse of the time. If the completion of the operation preparation of the exposure apparatus is not detected by the detection means, the operation of the exposure apparatus is thereafter detected by the detection means. An image forming apparatus comprising: a determination unit configured to determine completion of an exposure preparation operation of the exposure apparatus when the preparation completion is detected.
[0029]
(11) In the image forming apparatus described in (10), the exposure preparation elapsed time measured by the measuring unit is obtained by subtracting the image forming high voltage rise time from the exposure preparation completion scheduled time stored in the storage unit. An image forming apparatus, comprising: means for starting the rise of the image forming high voltage when the time coincides with the setting time, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation.
[0030]
(12) The image forming apparatus according to (10) or (11), wherein the exposure device is configured by a polygon motor and a laser exposure unit.
[0031]
(13) In the image forming apparatus according to the above (10) or (11), the image forming apparatus includes a high-voltage unit that generates the image forming high voltage, a developing unit, and a toner supply unit.
[0032]
(14) The image forming apparatus according to (10) or (11), wherein the exposure device is configured by a plurality of sets.
[0033]
(15) In the image forming apparatus according to (10) or (11), the image forming apparatus is configured by a plurality of sets.
[0034]
(16) In the image forming apparatus according to (10) or (11), the time required for the exposure device to complete the preparation for exposure is longer than the time required for the image forming device to complete the preparation for image formation. Forming equipment.
[0035]
(17) In the image forming apparatus according to the above (10) or (11), the storage unit has an exposure preparation completion time table storing a plurality of exposure preparation completion times, and the exposure device Based on the temperature and / or humidity in the image forming apparatus immediately before the start of the preparation operation, one of the exposure preparation completion schedule tables is selected from the exposure preparation completion schedule table, and the necessary exposure preparation completion schedule is selected. Image forming apparatus.
[0036]
(18) In the image forming apparatus according to (10) or (11), the storage unit has an exposure preparation completion time table storing a plurality of exposure preparation completion times, and the exposure device An image forming apparatus which selects one of the plurality of expected exposure preparation completion times according to an image forming mode at the time of starting a preparation operation and sets the required exposure preparation completion time as a required exposure preparation completion time.
[0037]
(19) An exposure device, and an image forming device that forms a toner image based on the latent image formed by the exposure device, and fixes the toner image on the transfer material to form an image on the transfer material. An image forming preparation method in an image forming apparatus for printing,
Step A for starting the exposure preparation operation of the exposure apparatus, Step B for measuring the elapsed time of the exposure preparation operation started in Step A, and the exposure time stored in the storage means for the elapsed time measured in Step B. An image forming preparation method, comprising: determining the completion of exposure preparation when the preparation completion scheduled time is reached.
[0038]
(20) In the image forming preparation method according to the above (19), when the elapsed time measured in the step B coincides with a time obtained by subtracting a rise time of an image forming high voltage from the expected exposure preparation completion time, An image forming preparation method, further comprising a step D of starting the rise of the image forming high voltage, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation.
[0039]
(21) An exposure device, and an image forming device that forms a toner image based on the latent image formed by the exposure device, and fixes the toner image on the transfer material to form an image on the transfer material. An image forming method in an image forming apparatus for printing, comprising:
A step A for starting an exposure preparation operation of the exposure apparatus, a step B for measuring an elapsed time of the exposure preparation operation started in the step A, a step E for detecting completion of operation preparation of the exposure apparatus, If the completion of the operation preparation of the exposure apparatus is detected in step E when the elapsed time measured by the step elapses by the expected completion time of the exposure preparation stored in the storage means, the exposure preparation of the exposure apparatus is When the elapsed time measured in step F for determining the operation completion and the elapsed time measured in step B has elapsed by the scheduled exposure preparation completion time stored in the storage means, the completion of operation preparation of the exposure apparatus is detected in step E. If not, the completion of the exposure preparation operation of the exposure apparatus is determined when the completion of the operation preparation of the exposure apparatus is detected in step E. Image forming preparation method and a step G.
[0040]
(22) In the image forming preparation method according to the above (21), when the elapsed time measured in the step B coincides with a time obtained by subtracting a rise time of an image forming high voltage from the expected exposure preparation completion time, An image forming preparation method, further comprising a step D of starting the rise of the image forming high voltage, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation.
[0041]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to examples of an image forming apparatus. The present invention is not limited to the form of the apparatus, but can be implemented in the form of a method, supported by the description of the embodiments.
[0042]
【Example】
(Example 1)
The configuration of the “image forming apparatus” of the first embodiment is the same as the configuration of FIG. 1 used in the description of the conventional example, so the description is referred to and the description is omitted here. The same members as those in the conventional example are denoted by the same reference numerals.
[0043]
FIG. 2 is a block diagram illustrating a configuration of a control controller that controls the image forming apparatus according to the present exemplary embodiment, and includes a CPU 201, an image reader control unit 202, an image signal control unit 203, a printer control unit 204, a ROM 205, a RAM 206, and an operation panel. It comprises a control unit 207. The CPU 201 controls the document reading unit 1R via the reader control unit 202 by executing a program stored in the ROM 205. The image signal control unit 203 accumulates image data of a document read from the document reading unit 1R or image data input to the image signal control unit via the network, and outputs print data to the printer control unit 204. The CPU 201 controls an operation panel (not shown) via the operation panel control unit 207. 208 is an A / D converter, and 209 is a temperature sensor. Although not shown in FIG. 1, the temperature sensor 209 can measure the temperature inside the image forming apparatus. The CPU 201 measures the temperature in the image forming apparatus by converting the output value of the temperature sensor 209 into digital data through the A / D converter 208.
[0044]
FIG. 3 is a diagram describing the area allocation of the ROM 205 and the RAM 206. Reference numeral 301 denotes a ROM which includes an area 303 in which a program is stored, an area 304 in which defined parameters are stored, and a polygon motor start-up time prediction table 305 described later. Reference numeral 302 denotes a RAM, which includes a stack area 306 and a variable area 307 necessary for executing a program.
[0045]
FIG. 4 is a diagram showing a correlation characteristic between the temperature in the image forming apparatus detected by the temperature sensor 209 and the time required for the polygon motor to complete the start-up (corresponding to the expected preparation completion time in the claims). As shown in the graph 401, when the inside of the image forming apparatus is at a low temperature of less than 50 ° C., the polygon motor requires much time to start up. Also, when the temperature becomes 90 ° C. or more, the time required for starting up the polygon motor also becomes long. A graph 402 is obtained by approximating the graph 401 to a table. For example, if the output of the temperature sensor is 40 ° C. or higher and lower than 50 ° C., the rise time of the polygon motor can be predicted to be 4.0 seconds. The table 402 is stored in the startup table 305 shown in FIG. 3, and the CPU 201 refers to the table for estimating the startup time of the polygon motor.
[0046]
If there is a correlation characteristic between the environmental humidity and the rise time of the polygon motor, the characteristic may be checked in advance, stored in a table, and referred to when predicting the rise time of the polygon motor. Further, the table 402 in FIG. 4 may be used in the monochrome image forming mode, and a predetermined value may be added to each value in the table in the color image forming mode to be used for the polygon motor start-up prediction. This is because the polygon mode generally requires a longer rise time in the color mode than in the monochrome mode.
[0047]
FIG. 5 is a subroutine showing an image forming preparation operation in the present embodiment. Upon receiving the print start command, the CPU 201 first samples the temperature inside the image forming apparatus using the temperature sensor 209 (see step 502 (indicated as S502 in the figure), and so on). Next, a time Tp required for starting the polygon motor is obtained from the sampling temperature from the table 402 (step 503). Next, in step 504, the time Tk required for raising the imaging high voltage is obtained. Next, in step 505, the driving of the polygon motor is started. Although not particularly shown, the polygon motor starts up only the polygon optical motor of the black optical system (13d) when the print job is monochrome, and the polygon motors of all the optical systems (13a to 13d) when the print job is color. Start the motor. Next, in step 506, a counter T1 for measuring an elapsed time from the start of the start of the polygon motor is initialized. Subsequently, in step 507, driving of the photosensitive drums (11a to 11d), the developing devices (14a to 14d), and the intermediate transfer belt 31 is started. The counter T1 is counted up, and when the value of the counter has elapsed by subtracting the image forming high voltage rising time Tk from the predicted polygon rising time Tp (steps 508 and 509), the image forming high voltage is raised in step 510. Start raising. Next, in step 511, the counter T1 is further counted up. When the value of the counter becomes equal to the predicted polygon rise time Tp, the image forming preparation operation is completed, and the subroutine ends (step 513).
[0048]
FIG. 6 is a timing chart showing the image forming preparation operation described in FIG. When a print start command is input in step 602, the state is changed from the print stopped state to the print ready state. In the print preparation state, in step 603, the polygon motor changes from a stop state to a start state, and in step 604, the photosensitive drum, the developing device, and the intermediate transfer belt change from the stop state to a start state. As shown in FIG. 5, when (Tp−Tk) time elapses from the start of the polygon motor start, at 605, the image forming high voltage starts to be started from the stop. Since the image forming high voltage rises at the time Tk and the polygon motor also rises at the time Tp from the start of the start, after the time Tp, it is possible to shift from the image formation preparation stage to the image formation possible stage as indicated by 601.
[0049]
Since the exposure preparation time may vary depending on the image forming mode, one of the exposure preparation times may be selected as the exposure preparation time according to the image forming mode at the time of starting the exposure preparation.
[0050]
As described above, in the present embodiment, it is noted that the rise time of the polygon motor has a correlation with the temperature inside the apparatus of the image forming apparatus. The table representing the table is prepared in advance in the control unit of the image forming apparatus, and based on the table, an optimum polygon motor start-up prediction time is obtained from the temperature inside the apparatus measured immediately before the preparation operation of the image forming operation. It is possible to realize the control to match the voltage start-up completion timing with the polygon motor start-up completion timing, and it is possible to complete the preparation for image formation at the optimal timing in response to the fluctuating polygon motor start-up time. become.
[0051]
(Example 2)
The configuration of the “image forming apparatus” according to the second embodiment is the same as the configuration of FIG. 1 used in the description of the conventional example, and thus the description is referred to and the description is omitted. The same members as those in the conventional example are denoted by the same reference numerals.
[0052]
FIG. 7 is a block diagram illustrating a configuration of a controller that controls the image forming apparatus according to the present exemplary embodiment, and includes a CPU 701, an image reader control unit 702, an image signal control unit 703, a printer control unit 704, a ROM 705, a RAM 706, and an operation panel. It comprises a control unit 707. The CPU 701 controls the document reading unit 1 </ b> R through the reader control unit 702 by executing a program stored in the ROM 705. The image signal control unit 703 accumulates image data of a document read from the document reading unit 1R or image data input to the image signal control unit 703 via a network, and outputs print data to the printer control unit 704. . The CPU 701 controls an operation panel (not shown) via an operation panel control unit 707. Reference numeral 708 denotes an A / D converter, and 709 denotes a temperature sensor.
[0053]
Although not shown in FIG. 1, the temperature sensor 709 can measure the temperature inside the image forming apparatus. The CPU 701 measures the temperature in the image forming apparatus by converting the output value of the temperature sensor 709 into digital data through the A / D converter 708. 710 is a polygon motor control register, and 711 is a polygon motor. By operating the polygon motor control register 710, the CPU 701 can not only drive the polygon motor 711 but also monitor whether or not the rise of the polygon motor has been completed by using the register 710.
[0054]
The configurations of the ROM 705 and the RAM 706 are the same as those in FIG. The relationship between the output value of the temperature sensor, the output value of 709, and the estimated startup time of the polygon motor is the same as that in FIG.
[0055]
FIG. 8 is a subroutine showing an image forming preparation operation in this embodiment. Upon receiving the print start command, the CPU 701 samples the temperature inside the image forming apparatus by the temperature sensor 709 (step 802). Next, from Table 402, a time Tp required for starting the polygon motor is obtained from the sampling temperature (step 803). Next, in step 804, the time Tk required for the rise of the imaging high voltage is obtained. Next, in step 805, the driving of the polygon motor is started. Although not particularly shown, the polygon motor starts up only the polygon optical motor of the black optical system (13d) when the print job is monochrome, and the polygon motors of all the optical systems (13a to 13d) when the print job is color. Start the motor. Next, in step 806, a counter T1 for measuring an elapsed time from the start of the start of the polygon motor is initialized. Subsequently, in step 807, driving of the photosensitive drums (11a to 11d), the developing devices (14a to 14d), and the intermediate transfer belt 31 is started. The counter T1 is counted up, and when the value of the counter has elapsed by subtracting the image forming high voltage rising time Tk from the polygon predicted rising time Tp (steps 808 and 809), the image forming high voltage is raised in step 810. Start raising. Next, in step 811, the counter T1 is further counted up. When the value of the counter becomes equal to the predicted polygon startup time Tp (step 812), whether or not the polygon motor 711 has started is monitored by the polygon motor control register 710 (step 812). 813) When the start of the polygon motor 711 is completed, the image forming preparation operation is completed, so the subroutine is terminated (817). On the other hand, if the polygon motor 711 has not started, the count T1 is further counted up. If the counter exceeds the counter Terr for judging a polygon motor abnormality error, NG is returned in order to urgently stop the image forming preparation operation. To end the subroutine (steps 815 and 816).
[0056]
FIG. 9 is a timing chart illustrating an example of the image forming preparation operation described with reference to FIG. When a print start command is input in step 902, the state changes from the print stopped state to the print preparation state. In the print preparation state, at 903, the polygon motor changes from a stop to a rising state, and at 904, the photosensitive drum, the developing device, and the intermediate transfer belt change from the stop state to a rising state. As shown in FIG. 8, when (Tp-Tk) time has elapsed from the start of the polygon motor start, at 905, the image forming high voltage starts to be started from the stop. The image forming high voltage rises during the time Tk. If the polygon motor has not yet risen at this time, monitoring of the rise of the polygon motor by the register 710 is started. When the rising (lock signal) of the polygon motor is detected, the process can shift from the image formation preparation stage to the image formation enabled stage as indicated by 901.
[0057]
As described above, according to the present embodiment, when the polygon motor does not reach the steady rotation within the predicted time for starting the polygon motor, the rising completion signal indicating the completion of the rising of the polygon motor indicates the rising completion state. By monitoring the start of the polygon motor, it is possible to realize the control to match the start timing of the start of the image forming high voltage and the start of the polygon motor, and complete preparation for image formation. It becomes possible to do.
[0058]
【The invention's effect】
As described above, according to the first to ninth, nineteenth, and twentieth aspects of the present invention, the optimum timing can be obtained without rotating the polygon motor preliminarily, and in response to the rising time of the polygon motor that fluctuates. To complete the preparation for image formation. According to the tenth to eighteenth aspects of the present invention, even when the rising of the polygon motor takes a longer time than the predicted rising time, the rising signal of the polygon motor is monitored. Accordingly, preparation for image formation can be surely completed.
[0059]
According to the second, eleventh, twenty-second, and twenty-second aspects of the present invention, the start of the image forming high voltage can be completed simultaneously with the completion of the exposure preparation.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of an image forming apparatus (copier).
FIG. 2 is a diagram illustrating a configuration of a control controller according to the first embodiment.
FIG. 3 is a diagram showing area allocation of ROM and RAM.
FIG. 4 is a diagram illustrating a relationship between a polygon motor start-up time and a temperature sensor output.
FIG. 5 is a flowchart illustrating processing of an image forming preparation operation according to the first exemplary embodiment.
FIG. 6 is a timing chart of an image forming preparation operation in the first embodiment.
FIG. 7 illustrates a configuration of a control controller according to a second embodiment.
FIG. 8 is a flowchart illustrating processing of an image forming preparation operation according to the second embodiment.
FIG. 9 is a timing chart of an image forming preparation operation in the second embodiment.
[Explanation of symbols]
201 CPU
205 ROM
206 RAM
305 Startup time table

Claims (22)

An image having an exposure device and an image forming device for forming a toner image based on the latent image formed by the exposure device, and printing the image on the transfer material by fixing the toner image on the transfer material In the forming device,
Storage means for storing in advance an expected exposure preparation completion time required from the start of the exposure preparation operation to the completion of the exposure preparation operation, and a lapse of time since the exposure apparatus started the exposure preparation operation Measuring means for measuring the elapsed time; and determining means for determining that the exposure preparation is completed when the elapsed time measured by the measuring means coincides with the expected exposure preparation completion time stored in the storage means. Image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the elapsed time measured by the measuring unit coincides with a time obtained by subtracting a start-up time of an image forming high voltage from a scheduled exposure preparation completion time stored in the storage unit. An image forming apparatus, further comprising means for starting the rise of the image forming high voltage, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation. 3. The image forming apparatus according to claim 1, wherein the exposure device includes a polygon motor and a laser exposure unit. 3. The image forming apparatus according to claim 1, wherein the image forming apparatus includes a high-voltage unit for generating the image forming high voltage, a developing unit, and a toner supply unit. The image forming apparatus according to claim 1, wherein the exposure device includes a plurality of sets. 3. The image forming apparatus according to claim 1, wherein the image forming apparatus is composed of a plurality of sets. 3. The image forming apparatus according to claim 1, wherein a time required for the exposure device to complete the preparation for exposure is longer than a time required for the image forming device to complete the preparation for image formation. apparatus. 3. The image forming apparatus according to claim 1, wherein the storage unit includes a scheduled exposure preparation completion time table storing a plurality of scheduled exposure preparation completion times, immediately before the exposure apparatus starts an exposure preparation operation. 4. Selecting one of the scheduled exposure preparation completion times in the scheduled exposure preparation completion time table based on the temperature and / or humidity in the image forming apparatus to obtain a required expected exposure preparation completion time. Image forming device. 3. The image forming apparatus according to claim 1, wherein the storage unit includes an exposure preparation completion time table storing a plurality of exposure preparation completion times, and the exposure apparatus starts an exposure preparation operation. 4. An image forming apparatus, wherein one of the plurality of scheduled exposure preparation completion times is selected to be a required scheduled exposure preparation completion time in accordance with the image forming mode. An image having an exposure device and an image forming device for forming a toner image based on the latent image formed by the exposure device, and printing the image on the transfer material by fixing the toner image on the transfer material In the forming device,
Storage means for pre-storing an exposure preparation completion time from when the exposure apparatus starts the exposure preparation operation to when the exposure preparation operation is completed, and measures an elapsed time since the exposure apparatus starts operation. Measuring means, detecting means for detecting the completion of operation preparation of the exposure apparatus, and when the elapsed time measured by the measuring means has elapsed by the expected time of exposure preparation completion stored in the storage means, the detecting means When the completion of the operation preparation of the exposure apparatus is detected, the completion of the exposure preparation is determined at the elapse of the time. An image forming apparatus comprising: a determination unit configured to determine completion of an exposure preparation operation of the exposure apparatus when the completion of operation preparation of the apparatus is detected. 11. The image forming apparatus according to claim 10, wherein the exposure preparation elapsed time measured by the measurement unit is equal to a time obtained by subtracting a start-up time of an image forming high voltage from an exposure preparation completion completion time stored in the storage unit. An image forming apparatus, comprising: means for starting the rise of the image forming high voltage when the image forming high voltage is started, and completing the rise of the image forming high voltage almost simultaneously with the completion of the exposure preparation. The image forming apparatus according to claim 10, wherein the exposure device includes a polygon motor and a laser exposure unit. The image forming apparatus according to claim 10, wherein the image forming apparatus includes a high-voltage unit that generates the image forming high voltage, a developing unit, and a toner supply unit. The image forming apparatus according to claim 10, wherein the exposure device includes a plurality of sets. The image forming apparatus according to claim 10, wherein the image forming apparatus includes a plurality of sets. 12. The image forming apparatus according to claim 10, wherein a time required for the exposure device to complete the preparation for exposure is longer than a time required for the image forming device to complete the preparation for image formation. apparatus. The image forming apparatus according to claim 10, wherein the storage unit has an exposure preparation completion time table storing a plurality of exposure preparation completion times, immediately before the exposure apparatus starts an exposure preparation operation. Selecting one of the scheduled exposure preparation completion times from the scheduled exposure preparation completion time table based on the temperature and / or humidity in the image forming apparatus to obtain a required scheduled exposure preparation completion time. Image forming apparatus. 12. The image forming apparatus according to claim 10, wherein the storage unit has an exposure preparation completion time table storing a plurality of exposure preparation completion times, and the exposure apparatus starts an exposure preparation operation. An image forming apparatus, wherein one of the plurality of scheduled exposure preparation completion times is selected to be a required scheduled exposure preparation completion time in accordance with the image forming mode. An image having an exposure device and an image forming device for forming a toner image based on the latent image formed by the exposure device, and printing the image on the transfer material by fixing the toner image on the transfer material An image forming preparation method in a forming apparatus,
Step A for starting the exposure preparation operation of the exposure apparatus, step B for measuring the elapsed time of the exposure preparation operation started in step A, and the elapsed time measured in step B are stored in the storage means in advance. And C. judging completion of exposure preparation when the scheduled time for exposure preparation completion is reached. 20. The image forming preparation method according to claim 19, wherein when the elapsed time measured in the step B coincides with a time obtained by subtracting a start-up time of an image forming high voltage from the expected exposure preparation completion time. An image forming preparation method, further comprising a step D of starting a voltage rise, wherein the rise of the image forming high voltage is completed almost simultaneously with the completion of the exposure preparation. An image having an exposure device and an image forming device for forming a toner image based on the latent image formed by the exposure device, and printing the image on the transfer material by fixing the toner image on the transfer material An image forming preparation method in a forming apparatus,
A step A for starting an exposure preparation operation of the exposure apparatus, a step B for measuring an elapsed time of the exposure preparation operation started in the step A, a step E for detecting completion of operation preparation of the exposure apparatus, In the case where the completion of the operation preparation of the exposure apparatus is detected by the step E when the elapsed time measured by the step E is equal to the expected time of completion of the exposure preparation previously stored in the storage means, the exposure of the exposure apparatus In step F, which determines the completion of the preparation operation, and when the elapsed time measured in step B has elapsed by the expected exposure preparation completion time stored in the storage means, the completion of operation preparation of the exposure apparatus is detected in step E. If not, the completion of the exposure preparation operation of the exposure apparatus is determined when the completion of the operation preparation of the exposure apparatus is detected in step E. Image forming preparation method characterized by comprising the steps G that. 22. The image forming preparation method according to claim 21, wherein when the elapsed time measured in the step B coincides with a time obtained by subtracting a start-up time of an image forming high voltage from the expected exposure preparation completion time, the image forming height is adjusted. An image formation preparation method, further comprising a step D of starting voltage rise, wherein the rise of the image forming high voltage is completed almost simultaneously with the completion of the exposure preparation.

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