JPH0218574A - Copying machine - Google Patents

Abstract

PURPOSE:To speedily obtain a copy by enabling plural-sheet continuous copying operation without idling a drum with a quick print switch when only one copy is taken although the plural-sheet continuous copying operation is carried out after stabilization by pressing a main print switch. CONSTITUTION:A console panel 60 is equipped with a form selection operation part 67, a ten-key 64, and an external main print switch 61A and the quick print switch 61B of a display part 62, etc., for various pieces of information. When the copying operation is started with the switch 61A, the photosensitive drum 6 idles twice and the start of an optical scanning device S is delayed until electrostatic charging characteristics are stabilized to obtain copies of uniform picture quality at high speed. When only one copy is taken without considering any difference in picture quality, the operation is started with the switch 61B and the drum 6 starts the copying operation without reference to the stabilization time, so that the copy is obtained in the shortest time of image formation and paper feeding.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a copying apparatus, and particularly to a copying apparatus that can quickly copy only one sheet.

(Prior art) When multiple sheets are continuously copied in an electrophotographic copying device, especially a high-speed, high-volume copying device, although high-speed processing is performed, it takes time for the charged state of the photoreceptor drum to stabilize. Therefore, there will be a change in image quality between the first and second copies, or between copies up to about the 10th copy. To prevent this, in conventional high-speed copying machines, until the charged state of the photoreceptor drum stabilizes,
Charge and erase while rotating the photoconductor drum idly.
After repeating the process about three times, the copying operation is started.

(Problem to be solved by the invention) However, when idling as described above, for example, 5
Even with high-speed copying machines capable of copying at a rate of 0 sheets per minute or more, the user must wait more than 4 seconds before making the first copy. However, when copying only one sheet, there is a problem in that it is very inconvenient to have to wait for more than four seconds even though it is a high-speed copying apparatus.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, it is an object of the present invention to provide a copying apparatus that can quickly copy only one sheet.

(Means for Solving the Problems) In order to achieve the above object, the present invention makes the photoreceptor drum idle, repeats charging and erasing, stabilizes the charging and state of the photoreceptor drum, and then performs a copying operation. It is characterized by having a main print switch that starts the copying operation, and a quick print switch that starts the copying operation immediately without idle rotation.

(Function) Since the present invention has the above-mentioned configuration, when a plurality of sheets are to be continuously copied, by pressing the main print switch, the photosensitive drum rotates idly, repeats charging and erasing, and after stabilizing the charging state. The copying operation is started, and multiple copies of uniform image quality can be obtained at high speed. On the other hand, 1
When copying only one sheet, pressing the quick print switch will start the copying operation without idle rotation of the photoreceptor drum, allowing you to quickly obtain a copy, and since it is only a single sheet, the image quality will be different. There is nothing to worry about.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 9.

FIG. 2 shows a slit scanning type electrophotographic reproduction apparatus. Second
In the figure, an original M placed on a glass plate 1a of an original platen 1 is irradiated with an exposure lamp 2, and image light from the original M passes through a slit 3, and is transmitted through an imaging lens 4 and a plurality of mirrors 5a. ~ Via the imaging optical system ■ consisting of 5d, etc.
The image is projected onto the photosensitive drum 6, which is rotated counterclockwise in the figure at a constant circumferential speed of ■.

The exposure lamp 2, slit 3, and first mirror 5a that constitute the scanning device S scan the original M by moving to the left in the figure at a speed of V/n (where n is the copying magnification). Also, the second
In order to maintain a constant imaging optical path length by the imaging optical system I, the mirror 5b and the third mirror 5C are moved to the left in the figure at a speed V/2n, which is half the moving speed V/n of the scanning device S mentioned above. Move to.

The image light scanned by the scanning device S forms an image on the photoreceptor drum 6, and the negative charge on the surface is selectively annihilated depending on the brightness of the image light.
An electrostatic latent image of this image light is formed.

Around the photosensitive drum 6, there is a charging device 7 that uniformly charges the surface thereof, and an inter-image eraser 57 that removes charges before and after the electrostatic latent image formed by projection imaging by the imaging optical system I.
, a developing device 8 that attaches toner to the electrostatic latent image and visualizes it.
, a transfer device 9 that transfers the toner image onto the recording paper P, a separation device IO2 that separates the recording paper P from the photoreceptor drum 6, a blade-shaped blade that removes excess toner adhering to the surface of the photoreceptor drum 6 after the transfer. A cleaning device 11, an eraser lamp 12 for erasing charges on the surface of the photoreceptor drum 6 after transfer, and the like are provided.

On the other hand, the recording paper P is stored in paper feed trays 13a and 13b installed in the copying apparatus main body
3b, one sheet at a time is taken out by a pickup roller 14a or 14b, passed through a pair of separating rollers 15a or 15b, fed into a sheet feeding path 17 with three pairs of transport rollers 16a to 16c interposed therebetween, and then fed into a sheet feeding path 17 interposed with three pairs of transport rollers 16a to 16c. It is sent to the transfer device 9 in synchronization with the formation of an electrostatic latent image on the photoreceptor drum 6.

Further, a paper feed stacker 19 is attached to the side of the main body X of the copying apparatus. Three types of recording paper P are accommodated in the three stages of paper feed trays 20a to 2Oc of this paper feed stacker 19, and the size of the recording paper P accommodated in these paper feed trays 20a to 20c is specified. If the recording paper P of that size is taken out one by one from the paper feed tray 20a, 20b or 20c by the pickup roller pair 21a, 21b or 21c, and after passing through the sorting roller pair 22a, 22b or 22c-. , three conveyor roller pairs 23a-2
3c is fed into the auxiliary paper feed path 25 in the main body X of the copying apparatus through the paper feed path 24 interposed therein, and after being conveyed to the timing roller pair 18 by the conveyance roller pair 26,
The image is sent to the transfer device 9 in the same manner as above.

The paper feed trays 13a, 13b, and 20a to 20c are equipped with a frame sensor that detects a slit light-shielding portion formed on a paper guide plate and a recording paper in order to detect the size of the recording paper P stored therein and the empty state of the paper. P
Detection means 55a, 55b, and 56a to 56c are provided, each of which includes a reflective photosensor or the like that detects reflected light from the sensor.

After the toner image has been transferred, the recording paper P is separated from the photosensitive drum 6 and is sent to the fixing device 28 by the conveyance heald 27. The fixing device 28 heats and melts the toner of the toner image transferred to the recording paper P.
”Secondly fix it.

The recording paper P that has passed through the fixing device 28 is transferred to a pair of transport rollers 29
A bypass path 32 is guided by a first conveyance switching lever 30 that is configured to switch the conveyance direction according to the copying mode, and leads to a paper ejection path 31 to the outside of the copying apparatus main body X and an inlet of the transfer device 9. sent to either one.

That is, when copying one original M onto one side of recording paper P (
(Hereinafter, this copying will be referred to as one-sided copying).Regardless of the copying magnification or the number of copies, the recording paper P after passing through the fixing device 28 is fed into the paper ejection path 31, and is transferred to the copying apparatus main body X by the paper ejection roller pair 33. It is discharged outside.

On the other hand, when copying one or two originals M onto both sides of recording paper P (hereinafter, this copying is referred to as double-sided copying), and when copying a combination of them onto one side of recording paper P (hereinafter, this copying (referred to as composite copying), the fixing device 28
After passing through, the recording paper P is fed into the bypass path 32.

An intermediate tray 34 for temporarily docking the fed recording paper P is interposed in the bypass path 32. In the case of composite copying, two conveyor roller pairs 35a, 3
5b to the intermediate tray 34. On the other hand, in the case of double-sided copying, two pairs of transport rollers 37a and 37 are guided by the second switching lever 36 before the intermediate tray 34.
The paper is fed into the reversing path 38 with a tray interposed therebetween, and after being turned over, it is fed into the intermediate tray 34.

The recording paper P in the intermediate tray 34 is taken out by the pickup row pair 39 when the second copy operation is started in the case of double-sided copying, or the second copy operation in the case of composite copying, and is taken out by the pick-up roller pair 39. 40, the transfer bag N9
The paper is fed into the paper feed path 11 leading to the paper. In the case of double-sided copying and composite copying, the toner image is transferred to the recording paper P in the same manner as in the case of single-sided copying by synchronizing with the timing roller pair 18 and sending it to the transfer device 9, and the toner image is transferred to the recording paper P by the fixing device 28. After being fixed, the sheet is discharged to the outside of the copying apparatus main body X through a sheet discharge path 31 provided with a pair of sheet discharge rollers 33.

A sorter 42 having 20 bins 41 for storing a plurality of discharged recording sheets P in groups is attached to the side of the main body X of the copying apparatus on the paper discharge path 31 side. This sorter 42 includes a pair of paper ejection rollers 3 of the main body X of the copying apparatus.
A receiving roller pair 43 is provided opposite to the receiving roller 3 . and,
The recording paper P discharged from the main body χ of the copying apparatus passes through the pair of receiving rollers 43 and then is sent out onto the bin 41 via a conveyance path 44 in the sorter 42 .

On the other hand, above the document table 1, an automatic document feeder 46 equipped with an automatic reversing device 45 is provided. This automatic document feeder 46 takes out a plurality of documents M placed on the document tray 4'7 one by one with a pink unroller 48, separates the documents M that has been taken out, passes them through a pair of rollers 49, and then transports them. After the document M is conveyed to a fixed position on the glass plate 1a by the heddle 50 and the prescribed copying operation is completed,
The document output tray 5 is moved by the conveyance rollers 51a and 51b.
2. Discharge onto the top. Further, when performing double-sided copying etc. from a double-sided document M, the automatic reversing device 45 cooperates with the transport heald 50 to reverse the front and back sides of the document M after copying of one side is completed. Feed it to the fixed position of the glass plate 1a of the table 1.

FIG. 3 is a professional diagram of the control device of this copying machine. A CPU 70 consisting of a microcomputer, which is the main part of this control device, is connected to various keys on an operation panel 60 whose detailed arrangement is shown in FIG. The copy conditions are set and displayed based on the input. Note that the CPU 70 controls the CPU 70 when a copying operation is not performed within a predetermined period of time (for example, 3 minutes) after a special copying condition is set or after one copying operation according to the copying condition is performed. has a built-in auto-reset function that automatically returns the copy conditions to standard copy conditions.

Then, the CPU 70 controls a regulator 71 for the exposure lamp 2 and a DC drive for the scanning device S according to the above-mentioned copying conditions.
A controller 73 for the motor DM, a driving stepping motor SM for changing the conjugate length of the imaging optical system I
controller 74 for charging bag W7, transfer device 9, and separation device 10, controllers 75 to 77 for each of charging bag W7, transfer device 9, and separation device 10,
A clutch that controls a fixing temperature controller 78 for the fixing device 28, a regulator 79 for the eraser lamp 12, a regulator 72 for the inter-image eraser 57, and also, although not shown, for intermittent driving of various rollers for conveying the recording paper P. etc., respectively.

A controller 73 for the control DC motor DM of the scanning device S receives drive control signals from the CPU 70 in forward and reverse directions to control operations such as movement, reversal, and stopping of the scanning device S. Also, from this controller 73, a driving DC
A signal obtained by shaping the pulse signal from the optical encoder attached to the motor DM is output to the CPU 70, and the C
The PU 70 detects the position of the scanning device S using this signal.

The controller 74 for the driving stepping motor SM of the imaging optical system I receives a driving control signal from the CPU 70 in the forward and reverse directions, and moves the imaging lens 4 and the fourth mirror 5d to a position where the conjugate length provides a set magnification. move it to.

In the map, the same reference numbers as in FIG. 1 indicate keys and LEDs on the operation panel 60, respectively.

FIG. 1 shows a part of the operation panel 60. As shown in FIG. 61
is a print key for starting a copying operation, and has two print keys 61A and 61B.

The large main print key 61A is located on this operation panel 6.
The copying operation is configured to start a copying operation under copying conditions set by various keys of 0. The small quick print key 61B is used for standard copying conditions (
Normally, the copying apparatus is configured to promptly start copying, as will be described later, by copying only one single-sided copy of the same size on an A4-sized recording paper P with automatic density setting.

A display device 62 digitally displays various information such as the number of copies and copy magnification. Reference numeral 63 denotes a copy density setting section in which copy density can be set by pressing two keys 63a and 63b. 63c is an automatic density setting key, 63d is an automatic density setting display LED that indicates that the automatic density setting key has been operated, and 63e is a density display LED group that displays the set copy density in steps. 64 is a numeric keypad, and by pressing an arbitrary key, the number of copies and the copy magnification can be set.

Reference numeral 65 represents an interrupt key, and reference numeral 66 represents a clear stop key for canceling settings such as the number of copies inputted using the numeric keypad 64 and interrupting the copying operation. 67 is a paper selection operation section;
a is a selection key, and 67b is a group of LEDs that display the type of recording paper P selected. 68 is a standard magnification setting operation section;
A state in which the copy of the original M is enlarged or reduced equally both vertically and horizontally at one of three preset magnifications by pressing any one of the four keys 68A to 68D, and the same size as the original M. It can be switched to the state where it is performed. 68
A to 68d are LEDs that display the respective standard magnifications.

Although not shown in the figure, the operation panel 60 has a function that divides the document M into separate recording sheets P when copying double-page spreads of the correspondence document.
A book mode key for specifying the book mode to be copied, double-sided copying, composite copying, binding margin shift, partial erasing, partial trimming, and sorting mode, grouping mode, stack mode, and non-sort mode using the sorter 42. Various keys are provided for setting various copying conditions, such as switching the recording paper P corresponding to the size of the document M, and an LED is provided for displaying each copying condition.

Further, a selection switch for selecting the size of recording paper P when performing a copying operation using the quick print switch 61B is disposed at an appropriate location on the side surface of the copying apparatus main body χ. As a specific example, even if a slide switch 53 for selecting the size of the recording paper P is provided as shown in FIG. 4(a), it is not possible to select the size using the setting button 54 as shown in FIG. Alternatively, a setting button 55 for selecting a paper feed tray may be provided as shown in FIG. 4(C).

Further, a display device 69 for digitally displaying the size of the selected recording paper P is provided near the quick print switch 61B of the operation panel 60. The display device 69 is also configured to display this when the selected recording paper P is empty, and is configured to notify that a copying operation cannot be accepted.

Next, the operation will be explained using specific numerical examples.

When the copying operation is activated by the print key 61, the recording paper P is sent out from the paper feed tray 13a or 13b by the pick-up roller 14a or 14b. Assuming that the system speed is 350 mm/sec, the distance from the leading edge of the recording paper P stored in the paper feed tray 13a to the timing roller pair 18 is 360 mm. .03
It takes seconds.

When the recording paper P is sent to the timing roller pair 18, it is detected by a microswitch and the optical scanning device S starts. The distance between the standby position of the scanning device S and the document M is 40
mm, a latent image at the leading edge of the document begins to be formed on the photosensitive drum 6 after 0.11 seconds. The distance from the projection section on the photosensitive drum 6 to the transfer device 9 is 100 mm. The distance from the timing roller pair 18 to the transfer device 9 is 75
mm, so in order to match the leading edge of the recording paper P in the transfer device 9 with the leading edge of the document on the photoreceptor drum 6, 25/350=0 is set after the scanning device S starts scanning the leading edge of the document.
．． The recording paper P waits on the timing roller pair 18 for 07 seconds. The length from the timing roller pair 18 to the paper ejection roller pair 33 is 550 mm, for example, A4 size horizontal feed (length 21 mm).
In order to completely feed out the timing roller (0 mm), it is necessary to feed the timing roller 760 mm from the 1st, so it takes 2.17 seconds. In total, the minimum time required is 3.38 seconds.

By the way, when the copying operation is started by the print switch 61, the recording paper P is fed out and
After 1=1.14 seconds, a latent image begins to be formed on the photosensitive drum 6. However, if the copying apparatus is left stationary for more than 5 minutes, the photosensitive drum 6 must be charged and erased at least twice until its charging characteristics become stable.

Otherwise, after a dark copy image is obtained on the first copy, the image density decreases on the second copy and thereafter becomes stable. In order to prevent this initial change, a processing time of 1.91 seconds or more is required to rotate the photosensitive drum 6, which has a diameter of 100 mm, twice and further to feed it 40 mm from the charging section to the projection section.

When starting the copying operation with the main print switch 61A, the recording paper P is fed out and the timing roller pair 18
The total time of 1.03 seconds for the optical scanning device S to reach the leading edge of the document, 0.11 seconds for the optical scanning device S to reach the leading edge of the document, and 0.07 seconds for the waiting time at the timing roller pair IB is 1.21 seconds, and the above-mentioned charging characteristic stabilization time. Since it is shorter than 1.91 seconds, the start time of the optical scanning device S is delayed so that the charging characteristics of the photosensitive drum 6 are stabilized, and the copying operation is started after securing the charging characteristics stabilization time. As a result, in the main print switch 61A, the stabilization processing time after pressing the switch is 1.
It took a total of 4.15 seconds to print the first sheet, including 91 seconds, 0.07 seconds waiting time to align the leading edge with the paper, and 2.17 seconds the time it took to eject the recording paper P from the position of the timing roller pair 18. You will get a copy of Therefore, even if continuous copying is performed, there is no change in copy density.

On the other hand, when the quick print switch 61B is pressed, the copying operation is started regardless of the charging characteristic stabilization time of the photoreceptor drum 6.
You will receive a second copy.

Note that the longer the distance between the paper feed tray and the pair of timing rollers, the longer it takes, so when copying using the quick print switch 61B, it is preferable to feed paper from the paper feed tray that is the shortest distance away.

A timing chart of the above copying operation is shown in FIG.

In Fig. 5, the solid line is the main print switch 61A.
The virtual line shows the copying operation using the quick print switch 61.8.

Next, the control operation will be explained based on a flowchart.

FIG. 6 shows the main routine that controls the overall copying operation. When this main routine is started by turning on the power, first, all internal registers, flags, RAM, etc. of the CPU 70 are cleared, and initial settings are performed to set the copying conditions to standard conditions (step #1). Next, ① Set an internal timer to set the length of the routine (Step #2). Next, input processing is performed from switches, sensors, etc. provided on each key and other parts of the operation panel 60 (step #3). After that, a "key processing" subroutine is called to perform copying condition change setting processing based on the input from each key of the operation panel 60, which is the copying condition setting means of the input information. Step #4
), the quick print switch 61B is used to call the "quick copy paper selection process" subroutine for selecting the size of recording paper P for copying (step #5).
, followed by setting the display data by the display device 62.
Dataset" subroutine is called (step #6). Thereafter, it is determined whether the copying operation can be started, that is, whether any abnormality has occurred (Step #7). If there is no abnormality, control signals and display signals are output (Step #8). The copying process subroutine is called to perform copying operations under various copying conditions (step #10). On the other hand, if there is any abnormality in the judgment at step #7, the "abnormality processing" subroutine is called, which stops the operation of each device involved in the copying operation, displays the occurrence of an abnormality, etc. (step #9), and checks the cause of the abnormality. It will be in a state waiting for the reset button to be operated after being removed. After returning from the "copy processing" subroutine, the state of the copying device, that is, the presence or absence of developing toner in the developing device 8, the presence or absence of recording paper P in the paper feed trays 13a and 43b, or the temperature abnormality of the fixing roller in the fixing device 28 is checked. After counting up the internal timer in step #11L (step #12), the CPU waits until the internal timer times up (step #13). If the internal timer times up, the process returns to step #2 and the above-described operations are repeated thereafter.

In the key processing subroutine, as shown in FIG. 7, it is first determined whether a non-copying operation is in progress (step #2).
If a non-copying operation is not in progress, such as during a 1L copying operation, the process returns directly. If the non-copying operation is in progress, then it is determined whether the quick print key 61B is on-edge (
Step #22). If it is not on-edge, proceed to step #27 to determine whether the main print key 61A is on-edge, and if it is on-edge, set the normal copy flag to 1, and if it is not on-edge, proceed to step #26 to print other items. Performs key processing and returns. On the other hand, if the quick print key 61B is on-edge in step #22, it is determined whether there is recording paper P set for quick copy (step #2
3) If there is no paper, display paper empty (step #29) and return. If there is paper, it is then determined whether it is the same size (step #24), and if it is not the same size, a copy prohibition display is displayed (step #30).
) Return, and if it is the same size, set the quick copy flag to 1 (step #25), perform other key processing (step #26), and return.

In the quick copy paper selection processing subroutine,
As shown in FIG. 8, first, it is determined whether or not copying is in progress (step 431L). If copying is in progress, the process returns; if not, next, select which size of recording paper P by using the selection switch. (Step #32), and select the paper tray containing the selected paper size (Steps #33 to #36).
, displays its size (steps #37-40), and returns.

In the copy processing subroutine, as shown in FIG. 9, it is determined whether the quick copy flag is 1 (step #41), and if the quick copy flag is 1, a quick copy operation is performed (step #41). 42) Return and if the quick copy flag is not 1, next determine whether the normal copy flag is 1 (step #43)
, ■ If not, return as is; if 1, return after performing a normal copy operation (step #44). Note that the system speed of the copying machine may be increased during quick copying.

The system speed is usually determined by the maximum torque allowed by the scanning device S at the minimum magnification, the paper conveyance speed at the fixing unit that can prevent the surface temperature of the fixing device 28 from decreasing during continuous copying, and the paper transport speed during continuous copying. Although it is determined based on parameters such as the rotation speed of the photosensitive drum 60 to ensure the ability to replenish toner into the developing device 8, in the case of the same size and only a single copy as in the quick copy of this embodiment, Normally, the system speed can be increased by 50% and still be within the criteria of the above parameters and yield a successful copy.

In the above embodiment, quick copying is performed only when the copying magnification is equal to the same magnification, but even if the copying magnification is other than that, the magnification remains the same or it takes some time to change the magnification. It is also possible to change the size of the image to the same size and copy it.

(Effects of the Invention) As is clear from the above description, according to the copying apparatus of the present invention, when making continuous copies of multiple sheets, by pressing the main print switch, the copying operation is started after the charging state is stabilized. This allows you to quickly obtain multiple copies with uniform image quality, or when making a single copy without worrying about differences in image quality, you can press the quick print switch to eliminate idle rotation of the photoreceptor drum. The copying operation is started immediately, and copies can be obtained quickly.

[Brief explanation of the drawing]

1 to 9 show an embodiment of the copying apparatus of the present invention,
Figure 1 is a plan view of the operation panel, Figure 2 is a schematic overall configuration diagram, Figure 3 is a schematic diagram of the control device, and Figures 4 (a) to (C).
) is a front view of the quick copy paper size selection means, Figure 5 is a timing chart of the operation, Figure 6 is the main control flowchart, Figure 7 is a flowchart of key processing, and Figure 8 is the quick copy paper selection process. FIG. 9 is a flowchart of the copying process. 1A 1B Photoconductor drum - Charging device Eraser lamp Main print switch Quick print switch

Claims (1)

[Claims] (1) A main print switch that starts the copying operation after the photoconductor drum is rotated idly and repeatedly charged and erased to stabilize the charged state of the photoconductor drum, and a quick switch that starts the copying operation immediately without idle rotation. A copying device comprising a print switch.