JPH0356979A - image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus that executes an image forming sequence while counting predetermined pulse signals.

[Conventional technology]

FIG. 14 is a sectional view showing an example of this type of image forming apparatus, and shows a full-color copying apparatus employing an electrophotographic recording system.

In the figure, 40 is a main body of the copying apparatus, and a transfer holder, that is, a transfer drum 13 is disposed approximately in the center. The transfer drum 13 is rotatably supported in the direction of the arrow in FIG. 14 (clockwise), and on the inner circumferential side of the transfer drum 13,
Transfer adsorption means, that is, adsorption charger 11, transfer V-electrifier 14. Charger for static elimination 17. A separation pressing roller 23 and a transmission type center (position sensor pair) 54 are respectively provided, and on the outer circumferential side of the transfer drum 13, the charge eliminating charger 17 is provided.
A static eliminating charger 18 is disposed facing the separation and pressing roller 23, and a charger 19. Separation claw 20
are arranged, and a position sensor pair 55 is arranged as a pair opposite to the position sensor pair 54. A transfer material adsorption means, that is, an abutting roller 12 is disposed facing the transfer drum cleaner 34 and the adsorption charger 11, and a photosensitive drum 2 and the like are disposed opposite the transfer charger 14, respectively. The contact roller 12 faces the downstream end of a paper feed guide 9 having a pair of registration rollers 10 for creating a certain amount of loop in the transfer material and sending out the transfer material at a predetermined timing. A pair of transmissive sensors 50 and 51 (pre-registration sensors) are disposed in the middle of the paper feed guide 9 to determine whether the fed transfer material is plain paper or an OHP film sheet.

At the upstream end of the paper feed guide 9, which branches into two directions,
Paper feed roller pair 24, big up roller 25, respectively
．． A paper feed roller pair 26 and a pickup roller 27 are provided. Further, a manual paper feed port 60, a manual paper feed length sensor 52, and a manual paper feed roller 53 are provided. A fixing roller 31. Pressure roller 30. A fixing device 22 having an oil sponge 32, a web 33, etc. is provided. A transfer material conveyance belt 21 is disposed between the fixing device 22 and the separation claw 20, and a motor 35 is disposed above the transfer material conveyance belt 21. The upper area of the copying apparatus main body 40 includes an original illumination lamp 4, a first mirror 5, a folding mirror 6. Lens system 7. A color image sensor 8 is provided respectively.

A developing means, that is, a horizontally movable developing device 1 is disposed in a lower region of the copying apparatus main body 40 in close proximity to the outer circumferential surface of the photosensitive drum 2 . Details of the horizontally moving developing device 1 will be described later.

The photosensitive drum 2 described above is rotatably supported in the direction of the arrow in FIG. As examples, the transfer drum 13, transfer charger 14, and horizontally moving developing device 1, which have already been described,
Cleaning member 16, primary charger 3, potential sensor 28
, the charger 15 for static elimination, the cleaning member 16, and the laser beam scanner unit 29 etc. are arranged in close proximity to the charger 15 for static elimination.

To be more specific about the horizontally movable developing device 1, the horizontally movable developing device 1 includes a movable body 1a that can be moved substantially horizontally in the lateral direction in FIG. It includes a developer IM, a cyan developer IC, a yellow developer IY, and a black developer IBK. Magenta developer IM, cyan developer IC, yellow developer IY,
Each black developer IBK has four
toner hoppers are arranged in parallel in the surface direction of FIG. They are connected by flexible means, and developer material can always be replenished even if the magenta developer IM, cyan developer IC, yellow developer IY, and black developer 1BK are moved in the horizontal direction by the movable body 1a. It is composed of

A case in which copying is performed in full color mode using the apparatus configured as described above will be described below. First, the outer peripheral surface of the photosensitive drum 2 is charged almost uniformly by the primary charger 3, and then an original (not shown) is scanned while being illuminated by the original illumination lamp 4. ．． Ra5. Folding mirror 6
．． A color image is formed on a single-shot sensor 8 via a lens system 7. The reflected light is color-separated by the color image sensor 8, and when a magenta signal is generated by the color separation, the magenta image signal is sent to the laser beam scanner unit 29.
The laser beam E emitted from the laser beam scanner unit 29 modulates the laser beam E and the laser beam modulated by the magenta image signal emitted from the laser beam scanner unit 29 performs image exposure, and an electrostatic latent image is formed on the outer peripheral surface of the photosensitive drum 2. It is formed.

The electrostatic latent image formed on the photosensitive drum 2 is developed in advance by a magenta developer 1M waiting at a development position facing the outer peripheral surface of the photosensitive drum 2 shown in FIG. .

On the other hand, the transfer material sent toward the transfer drum 13 at a predetermined timing via the paper feed gago 9 and the pair of registration rollers 10 is electrostatically transferred to the transfer drum 13 by the adsorption charger 11 and the contact roller 12. Wrapped around the outer surface.

The rotational speed of the transfer drum 13 described above is normally set to be synchronized with the rotational speed of the photosensitive drum 2, and the toner image formed on the outer peripheral surface of the photosensitive drum 2 by the magenta developer 1M is transferred to the transfer charger 14. is transferred onto the transfer material. The transfer drum 13 continues to rotate at the rotational speed described above, and prepares for transferring a toner image formed on the outer peripheral surface of the photosensitive drum 2 with toner of a new color (cyan color in FIG. 14). .

The photosensitive drum 2 is charged again by the primary charger 3 after the static electricity is removed by the charger 15 and the toner remaining on the photosensitive drum 2 is cleaned by the cleaning member 16.
It is electrically charged substantially uniformly by , and is subjected to image exposure by laser light E modulated by a cyan image signal.

On the other hand, the cyan developing device 1C waits at the above-mentioned developing position by moving the movable body 1a in the direction of the arrow in FIG. The electrostatic latent image formed is developed to form a cyan toner image. The same process is continued for the original image information corresponding to the yellow color and the original image information corresponding to the black color, and when the transfer of the toner images of the four colors to the transfer material is completed, the toner images are transferred onto the transfer material. 17. The four-color toner image is removed by the charger for static electricity removal.
After being neutralized in step 18 and re-charged by a charger 19, the transfer material is separated from the transfer drum 13 by a separating claw 20. The transfer material separated from the transfer drum 13 by the separation claw 20 is sent to the fixing device 22 by the transfer material conveyance belt 21, and a series of copying sequences are completed, and a desired full-color print image is obtained.

Figure 15(a). 14(b) is a perspective view and a cross-sectional view illustrating the structure of the transfer drum 13 shown in FIG. 14. FIG.

This color copying apparatus attracts copy paper to a cylindrical transfer drum 13 using an attraction charger 11. For example, for A4 size (short side), the first page is shown in Figure 15 (b).
The second sheet is sucked at a position 302 on the opposite side of the first sheet by 180 degrees so that its tip overlaps the cut 301 of the sheet. However, in the case of an OHP film sheet, if an attempt is made to overlap the leading edge of the OHP film sheet with the cut 301, which has a strong stiffness and weak suction force, it will easily peel off from the transfer drum 13, so it cannot be suctioned.

In addition, OHP film sheets are often fed without specifying the direction (longitudinal or short side), and when paper is fed in the longitudinal direction, it is necessary to If it is attracted from a certain position 302, it will hang on the frame 304.

Therefore, the fed copy paper is detected by the pair of transmissive sensors 50.
51, if it is determined that the film is an OHP film,
Even if there is a cut 301, there is a position 302 on the opposite side of 180 degrees.
A predetermined position where it can be adsorbed in the longitudinal direction, that is, O
The HP film sheet is suctioned from a suction position 303.

That is, it is adsorbed like a HP film sheet 305 in the longitudinal direction.

[Problem to be solved by the invention] In this way, the difference in the types of recording media to be fed is the first
It is determined based on the output detected by the pair of transmissive sensors 50 and 51 disposed immediately before the pair of registration rollers 10 shown in FIG. Ru. This transfer sequence timing control is performed in synchronization with a position signal (for example, 2 pulses per drum rotation) detected by a position sensor pair 54, 55 provided at a predetermined position on the transfer drum 13, provided inside the copying apparatus main body 40. This is achieved by controlling the drive of the pair of registration rollers 10 and the drive of the optical system motor using timing synchronized with count data counted by a counter circuit provided in a controller section (not shown).

For this reason, there is an inevitable waiting time until the type of recording medium is determined and the count data that determines the transfer timing for that recording medium is determined, which reduces the throughput of the entire device. was there.

Therefore, if the circumferential length of the transfer drum 13 is configured such that it can attract two sheets of A4 longitudinal hand-fed copy paper, for example, it is not necessary to determine the type of recording medium as described above, and the throughput can also be improved. However, it cannot be denied that an economical problem may arise in which the size of the device increases and the cost of the device increases significantly.

The present invention was made to solve the above problems, and it is possible to transfer the recording medium by performing counter processing in advance based on shared count data transmitted before the recording medium determination processing. It is an object of the present invention to provide an image forming device capable of improving throughput by significantly advancing the timing of transfer drive to a drum.

(Means for Solving the Problems) The image forming apparatus according to the present invention includes a changing means for arbitrarily changing and setting the counting conditions set in the counter means based on the output state of each sensor during the counting process by the counter means. It was established.

Further, a feeding unit that feeds a recording medium, a transfer drum unit that can hold a predetermined number of recording media fed by this feeding unit, and a first drum unit that determines the type of recording medium fed by the feeding unit. A sensor, a second sensor that detects a predetermined rotational position of the transfer drum unit, and a feeding timing changing device that arbitrarily changes and sets the counting condition set in the counter device based on the output states of the first and second sensors. It was established.

[Effect]

In this invention, during counting processing by the counter means, the changing means arbitrarily changes and sets the counting conditions set in the counter means based on the output state of each sensor, and before the counting conditions determined by the outputs of each sensor are determined. It is possible to start counting processing by the counter means.

Further, while the counting means starts a predetermined counting process based on the output of the second sensor, the feeding timing changing means is set in the counter means when the counting condition is determined based on the output of the first sensor. The counting conditions set are arbitrarily changed and set, and the control means is enabled to start driving the feeding unit when the changed counting process is completed.

(Embodiment) FIG. 1 is a block diagram illustrating the configuration of an image forming apparatus showing an embodiment of the present invention, in which 100 is a CPU, a ROM
Each part is comprehensively controlled based on a control program stored in 101. A RAM 102 mainly functions as a work memory and manages various status information.

103 is an interface circuit; 104 is a transfer drum home position sensor (transfer drum HP sensor);
Corresponding to the position sensor pair 54.55 shown in Figure 4,
Among the sensors of this invention, this one functions as a second sensor. 105 is a pulse encoder, 106 is a BD
A signal generation circuit 107 is an image processing circuit that performs predetermined image processing (shading correction, gamma conversion processing, etc.) on input image data.

On the 10th, among the sensors of the present invention, the pre-registration sensor functioning as the first sensor detects the type of recording medium being fed (plain paper and OHP film sheet in this embodiment). Reference numeral 109 denotes a manual feed length detection sensor, and 110 denotes a developing unit motor controller, which controls the driving of the developing roller 111. An optical system motor controller 112 controls the drive of the optical scanning system drive motor 113. 114 is a transfer drum sensor.

FIG. 2(a) is a block diagram illustrating the configuration of the optical system motor controller 112 shown in FIG.
is a microprocessor, and 502 is an external counter.

A pulse signal HPI is input to the external interrupt input terminal INT1. Further, a clock CLK of a constant period is sent from the microprocessor 501 to an external counter 5.
The count-up signal of the external counter 502 is input to the external interrupt terminal INT2 of the microprocessor 501 as the motor start signal MSTART. Further, the external counter 502 includes counters 503 and 504 having a time function, and these counters 503.
Control register 5 for setting modes such as start/stop of 504 and read/write of count value
05 etc.

Reference numeral 501a denotes a changing means that also serves as a feeding timing changing means, and controls each part according to the procedure of a flowchart described later.

That is, during counting processing by the counter means (counters 503, 504), the count conditions set in the counters 503, 504 are applied to each sensor (pre-register sensor 108).
．． The transfer drum HP sensor 104) can be arbitrarily changed and set based on the output state, and the counting process by the counter means can be started before the counting conditions determined by the outputs of each sensor are determined.

Further, a counting means (counter 5
03.504) starts a predetermined counting process, the first sensor (in this embodiment, the pre-register sensor 108)
When the count conditions are determined by the output of
3. When the count conditions set in 504 are arbitrarily changed and the changed count processing is completed, the control means (in this embodiment, the microprocessor 501
) is a feeding unit (registration roller pair 10 and motor 11
3, etc.).

As a result, before the count value for the external counter 502 is determined based on the sensor output of the transfer drum HP sensor 104, a pseudo count value (in this embodiment, a count value assumed to detect plain paper) is displayed on the external counter 502.
is set to start the count process, and when the regular count value for the external counter 502 is determined corresponding to each sensor output, the CPU 100 uses the changing means 501a to change the set count value to each pre-register sensor 108,
The microprocessor 501 performs an arbitrary change based on the sensor output state of the transfer drum HP sensor 104 (in this embodiment, counting processing using an OHP film sheet), and based on the count state of the external counter 502 based on the changed count value. The copying sequence is executed while controlling the drive timing of each unit (in this embodiment, the optical system motor, etc.) based on a flowchart described later.

FIG. 2(b) is a timing chart illustrating the control operation of the motor 113 shown in FIG. 2(a).

As you can see from this diagram, optical system motor controller 1
By providing a total of two counters, counters 503 and 504, in 12, it is possible to count any time as long as it is shorter than two periods of the pulse signal HP1.

The operation shown in FIG. 1 will be explained below.

The ROMI○1 has a built-in control program, etc., and also stores non-volatile fixed data. R.A.
The MI○2 stores various data given to the CPU 100 from the outside via the interface circuit 103, and is also configured to read out the various data stored by the CPU 100.

The interface circuit 103 is for connecting the CPU 100 and various external devices. The transfer drum HP sensor 104 is disposed within a region where one detection target (not shown) provided on the rotating transfer drum 13 can be detected. The transfer drum HP sensor 104 sends a predetermined pulse signal to a detection signal at a reference position set on the transfer drum 13 every time the object to be detected passes through the detection area of the transfer drum HP sensor 104 due to rotation of the transfer drum 13. It is designed to be output as . The transfer drum HP sensor 104 outputs a pulse signal HP (fifth
6) is output.

The pulse encoder 105 detects the rotational speed of the motor 35 that rotationally drives the transfer drum 13 and outputs a predetermined pulse signal. The BD signal generation circuit 106 is provided within the laser beam scanning unit 29 and outputs a well-known horizontal synchronization signal BD.

The image processing circuit 107 performs shading correction on the image signal from the color image sensor 8 of known technology, and performs processing such as brightness density conversion, scaling, and movement.

Front register sensor 108 (in this embodiment, a transmission type sensor pair (
The pre-registration sensor) 50 and 51) is a transmission type sensor, which is disposed immediately before the pair of registration rollers 10, and detects whether the fed transfer material is plain paper b) OHP film sheet. ．． Detect the presence of water. In particular, the OHP film sheet is as shown in Figure 3. As shown in Figure 4, there are A4 size short feed paper (Boat rate) and A4 size long feed paper (Landscape) depending on the paper feed direction, both of which have a detection band of 8 mm width at the leading edge in the feed direction. Since the light beam of the transmission type sensor does not pass through this portion, the leading edge of the OHP film sheet can be detected.

Further, it is possible to distinguish between a 014P film sheet and plain paper based on the difference in sensor input from plain paper, the entire paper of which does not transmit light.

The manual feed length detection sensor 109 detects the length of paper fed from the manual paper feed port 60.
The type of film sheet (A4 long feed or A4 short feed) can be determined by the detection output of this manual feed length detection sensor 109.

Further, the transfer drum sensor 114 detects whether the paper attracted to the transfer drum 13 has peeled off or not, and detects whether the paper has been attracted to the correct position.

A developer motor controller 110 controls the operation of the moving body 1a.

The optical system motor controller 112 controls the operation of the optical system. That is, the motor 113 drives and controls the document irradiation lamp 4 , the first straightening roller 5 , and the main folding roller 6 .

The optical system motor controller 112 also includes a CPU.
At 100, a pulse signal HP from the transfer drum HP sensor 104 that is determined to be necessary for document scanning is input as a pulse signal HPI.

Next, while referring to FIGS. 5 to 8 and FIGS. 9(a) and (b), the counters 503 and 504 shown in FIG.
The operation will be explained in detail.

5 and 6 show the counter 50 shown in FIG. 2(a).
FIG. 5 is a timing chart illustrating the operation of the counting process of 3.504. FIG. 5 corresponds to the operation timing according to the present invention, and for comparison, FIG. 6 shows the operation timing of the conventional system.

Components that are the same as those in FIG. 2(a) are designated by the same reference numerals.

FIG. 7 shows the counters 503 and 50 shown in FIG. 2(a).
4 is a flowchart showing an example of a count start routine of No. 4; Note that (1) to (5) indicate each step.

First, the microprocessor 50.1 sets the flag F-ST.
Determine whether ART is the initial value ('OJ) (1
), YES? A constant count value of the j-rubber counter 503 is set, and counting processing is started (2).

Next, set the flag F-START to "1" (3
) Return.

On the other hand, if the determination in step (1) is No, a count value is set in the counter 504 and counting processing is started (4). Then the flag F-STAR
Set T to "0" (5) and return.

FIG. 8 is a flowchart showing an example of a motor start routine for the motor 113 shown in FIG. 2(a).

Note that (1) to (6) indicate each step. When the motor start MSTART is input to the external interrupt input terminal INT2 of the microprocessor 501 by the counters 503, 504, etc. of the external counter 502, this flow starts and the flag F-STOP is set to the initial value, that is, "0".
” (1) If YES, stop the counter 503 (2) Flag F-STO
Set P to "1" (3), proceed to step (6), and start the motor 113.

On the other hand, if the judgment in step (1) is N'O, the counter 504 is stopped (4) Flag F-STOP
is set to "O" (5), -11-Ichiyuki 113 is started, and the process returns.

Figure 9(a). (b) is a flowchart showing an example of an image forming reed sequence in the image forming apparatus according to the present invention. Note that (1) to (15) indicate each step.

When the operator turns on the power, CPUIO○ starts this flow, and when the start key of the operation unit (not shown) provided on the copying machine main body 40 is operated,
Information such as paper feeding means, magnification, development color, etc. set on the operation unit is taken in (1).

At this time, it is assumed that the paper feeding means is manual paper feeding and a four-color full-color mode, that is, a mode in which development is performed using magenta, cyan, and yellow black toners, is selected.

The CPU ○○ outputs the BD signal from the BD signal generation circuit 106 and the pulse encoder 10 based on the pulse signal HP.
Various input/output devices (I/O) are controlled by counting the encoder output from 5.

Start key Manually starts the motor 35 of the transfer drum 13.
ONL, the operation is not executed until the pulse signal HP is input, and after the pulse signal HP is input, the paper feed signal FEED is turned ON.
Do N (2). As a result, the transfer material set in the manual paper feed port 60 is fed by the manual paper feed roller 53. . At the same time, the CPU 100 monitors the manual feed length detection sensor 109 to measure the length of the manually fed paper (3).

Here, assuming that plain paper is being fed, select position 301.
The delay time data DELDATA with respect to the pulse signal HPI is transmitted to the optical system motor controller 112 at the timing TMI shown in FIG. 5C so that an image can be output at the tip (4). This is a timing that precedes timing TTMI in FIG.

Next, when the leading edge of the paper that has been fed longer than the maximum paper size reaches the registration roller pair 10 from the manual feed length detection sensor 109 to the registration roller pair 10, the input of the manual feed length detection sensor 109 indicates that there is no paper. It has become. The fed paper is formed by a pair of paper feed rollers 24 to form a loop to remove the skew of the paper fed by the pair of registration rollers 10, and the fed paper is plain paper or an OHP film sheet. In order to check whether the
Wait until 0.51 manual paper is available (5). As mentioned above, the pre-register sensors 50 and 51 are transmission type sensors, and when an OHP film sheet is fed, only the leading edge of the paper is detected as being present, and after a certain period of time has elapsed, (6) When OHP film sheet detection passes the pre-register sensor 50.51 (7), if it is detected that there is no paper, it is determined that the fed paper is OHP film paper. (8) If it is detected that there is paper, it is determined that it is plain paper (9). After that, register roller 1
A loop is created at 0 (lO), and it waits at the position where the registration roller pair 10 is arranged until the timing matches the suction position.

Also, at this time, the manually fed paper size is A.
Since it is determined that the size is 4, the monitoring of the manual length sensor detection 109 is ended (1l).

Next, it is determined whether the detected paper is a ○HP film sheet (l2), and if YES, the transfer drum 13 is moved to position 3.
The optical system motor controller 11 controls the drive of the pair of registration rollers 10 so that 03 can be attracted to the top (l3).
A delay time change command of the pulse signal HP1 is transmitted at timing TM2 shown in FIG. 5 (14) so that the image can be outputted with position 303 as the leading edge (14), and the process moves to the next control. As a result, the count values of counters 503 and 504 are changed as described later.

On the other hand, if the judgment in step (12) is NO, position 3
Is it possible to output images by adsorption from 01? The drive of the stroller pair 10 is controlled (15), and the next control is started.

Note that the delay time change command described above is a 3-byte command. The first byte is data indicating the need to change the delay time, and the next two bytes indicate the value to be changed, that is, the increase/decrease data of the delay time.

FIG. 10 is a flowchart showing an example of a delay time changing procedure by the changing means 501a shown in FIG. 2(a). Note that (1) to (3) indicate each step.

First, it is determined whether the flag F-START is r, or not (1). If YES, the counter value of the counter 504 shown in FIG. 2(a) is changed based on the delay time increase/decrease data (2). ) Return.

On the other hand, if the judgment in step (1) is No, then in Figure 2 (
As shown in a), the counter value of the counter 503 is changed based on the delay time increase/decrease data (3) and the process returns.

As a result, the output timing of the motor start signal MSTART can be significantly shortened between the case shown in FIG. 5 and the case shown in FIG. It turns out.

In addition, in the above embodiment, changing the counter value! As explained above, due to state changes that occur during a copy sequence, a situation may occur in which the counting process must be canceled and the counting process must be executed again. The cancellation process will be explained below.

FIG. 11 is a timing chart illustrating an image forming sequence of an image forming apparatus showing another embodiment of the present invention.

Note that this corresponds to the case of monochrome continuous copy processing.

FIG. 12 is a flowchart showing an example of a counter cancellation processing procedure in the image forming apparatus according to the present invention. Note that (1) to (4) indicate each step.

First, the CPU 100 determines whether the pre-register sensors 50 and 51 have detected a paper out state for a certain period of time (1).
, (2) If No, move on to the next process, Y
If ES (recording medium conveyance delay has occurred), the command to cancel the pulse signal HPI is sent to the optical system motor controller 1.
12 (3), stops the delay time counter (see timings TM1 and M2 shown in FIG. 11), and outputs the next pulse signal HP as the pulse signal HPI (4).
), move on to the next process.

FIG. 13 is a flowchart showing an example of the processing procedure of the optical system motor controller 112 caused by a cancellation command in the image forming control device according to the present invention. In addition, (1) to (
5) shows each step.

First, it is determined whether the flag F-START is "O" (1). If YES, the counter 504 (functioning as the latest counter) is stopped (2), and the flag F-S is
Set TART to "1" (3) and return.

On the other hand, if the determination in step (1) is No, the counter 503 is stopped (4), the flag F-START is set to "O" (5), and the process returns.

[Effects of the Invention] As explained above, the present invention includes a changing means that arbitrarily changes and sets the counting conditions set in the counter means based on the output state of each sensor during the counting process by the counter means. It becomes possible to start the counting process of the counter means for controlling the driving timing of each unit used in the copying sequence before the count value or count condition is determined, and it is also possible to start the counting process of the counter means for controlling the drive timing of each unit used in the copying sequence. It becomes possible to interrupt the counting process during the counting process and restart the counting process to determine the timing adjustment again.

Therefore, it is possible to arbitrarily change or interrupt the processing timing during the counting process, and it is possible to arbitrarily change the setting of the control sequence before finalizing the counting process as in the conventional case.

Further, a feeding unit that feeds a recording medium, a transfer drum unit that can hold a predetermined number of recording media fed by this feeding unit, and a first drum unit that determines the type of recording medium fed by the feeding unit. A sensor, a second sensor that detects a predetermined rotational position of the transfer drum unit, and a feeding timing changing device that arbitrarily changes and sets the counting condition set in the counter device based on the output states of the first and second sensors. Because of this provision, the feeding timing of the recording medium in the image formation sequence can be made much earlier than in the past, resulting in an excellent effect of greatly improving the throughput of image output.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating the configuration of an image forming apparatus showing an embodiment of the present invention, FIG. 2(a) is a block diagram illustrating the configuration of the optical system motor controller shown in FIG. 1, FIG. 2(b) is a timing chart for explaining the control operation of the motor shown in FIG. 2(a), and FIGS. 3 and 4 are for explaining the transport mode of a PHP film sheet as a recording medium. FIGS. 5 and 6 are timing charts for explaining the counting process of the counter shown in FIG. 2(a), and FIG. 7 is a timing chart for explaining the counting process of the counter shown in FIG. FIG. 8 is a flowchart showing an example of a count start routine, and FIG. 9(a) is a flowchart showing an example of a motor start routine for the motor shown in FIG. 2(a).
) and (b) are flowcharts showing an example of the image forming sequence in the image forming apparatus according to the present invention, and FIG.
FIG. 2(a) is a flowchart showing an example of the delay time changing procedure by the changing means shown in FIG. FIG. 12 is a flowchart showing an example of the counter cancellation processing procedure in the image forming apparatus according to the present invention, and FIG. 13 is a flowchart showing an example of the processing procedure of the optical system motor controller caused by a cancellation command in the image forming apparatus according to the invention. , FIG. 14 is a cross-sectional view of the structure of an example of this type of image forming apparatus, and FIG. 15(a)
, (b) are a perspective view and a cross-sectional view illustrating the structure of the transfer drum shown in FIG. 14. In the figure, 10 is a registration roller pair, 13 is a transfer drum, and 5
0.51 is a transmission type sensor pair, 54.55 is a position sensor pair, 100 is a CPU, 501 is a microprocessor, 501a is a changing means, and 502 is an external counter. Figure 2 (a) 502. External counter 3 Figure 4 Figure 4 AJR size OHP paper 7 Figure 8 Figure 9 Figure (a) Figure 9 (b) Figure 10 Figure 12 Figure 13 Figure 14 Figure 1 4 10 Stroller Nana] 3 Transfer drum 5455 Elbow'/3〉Hi〉Saka 302

Claims (2)

[Claims] (1) It has a plurality of units for executing an image forming sequence, a plurality of sensors for detecting the state of the image forming sequence, and a counter means for counting a predetermined count value based on the output state of each sensor. In an image forming apparatus having a control means for controlling drive timing of each unit based on a count state by a counter means, during counting processing by the counter means, the count condition set in the counter means is changed to the output state of each sensor. An image forming apparatus characterized by comprising a changing means for arbitrarily changing settings based on the image forming apparatus. (2) Determine a feeding unit that feeds a recording medium, a transfer drum unit that can hold a predetermined number of recording media fed by this feeding unit, and the type of recording medium fed by the feeding unit. a first sensor that detects a predetermined rotational position of the transfer drum unit; a second sensor that detects a predetermined rotational position of the transfer drum unit;
2. The image forming apparatus according to claim 1, further comprising: a feeding timing changing unit that arbitrarily changes and sets the feeding timing based on the output state of the second sensor.