JPS5976278A - Recording apparatus - Google Patents

Abstract

PURPOSE:To perform high quality image recording to the desired position of transfer paper at a high speed, by controlling the output of image data to an image support by a control signal obtained after rotating said image support for a predetermined time while further controlling the feeding of the transfer paper by the other signal after a predetermined time. CONSTITUTION:A control circuit 57 responds to the print signal from the computer 56 of an information output apparatus to revolve a photosensitive drum being an image support and charging devices 8, 9, 13, a developing device 11 and a cleaning apparatus 12 other than a transfer charging device 20 are turned ON. When the forward rotation of said drum 7 is performed for a predetermined time, a first control signal is supplied to the computer 56 from the circuit 57 to control the output of image data from the computer 56 to the drum 7 and, after a further predetermined time is elapsed, the feeding transfer paper 15 is controlled though a tractor 16 by the second control signal from the computer 56 and moved in synchronous relation to the drum 7 at a speed same to that of said drum 7. By this mechanism, high quality image recording can be performed to the desired position of the transfer paper at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention particularly relates to a recording device that is effective for quickly and accurately printing out character/graphic information from a computer or the like. An electrostatic latent image is formed on the support, and the electrostatic latent image is covered with colored particles (
To provide a recording device that outputs a high-quality hard copy at high speed by visualizing the image using toner), transferring the developed image to a continuous transfer member, and further fixing the image. Conventionally, mechanical impact printers have been widely used as output devices for electronic computers and the like. 2. Description of the Related Art Recent advances in electronic technology have increased the processing power of arithmetic units and storage devices, and as a result, there is a demand for output printers with capabilities that exceed those of conventional mechanical impact printers.

A variety of non-impact printers have been developed to meet these demands, but among them, printers that use information from a computer as an electrostatic latent image are known for their high speed, print quality, and low running costs. This electrostatic latent image is formed on a support such as a body, and is developed with toner. The developed image is transferred to plain paper, and the toner image on the plain paper is fixed and output. So-called transfer-based electrostatic recording and electrophotographic recording are excellent.

Generally, a recording device starts outputting data from an information output device and feeds paper in response to a print command. However, in transfer recording, if data output start and feeding are controlled in this way, it may not be possible to obtain a high quality recorded image. In other words, if data output is started at the same time as the photoconductor starts rotating in response to a print command, a latent image will be formed on the photoconductor without sufficient preparation for image formation on the photoconductor, which may result in poor image quality on the first sheet. . However, if you start data output after making sufficient preparations for image formation,
If feeding of the transfer paper is started based on a print command, the latent image formed on the photoreceptor based on the output data may not accurately match the transfer paper.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and provide a recording device that can record information at a desired position on a transfer sheet at high speed and with high quality. That is, in a recording apparatus having an image support, and a feeding means for feeding a transfer material to transfer the image formed on the support onto a transfer material. , an information output device for outputting image data to the image forming means; means for generating a rod 1 control signal after rotation of the support for a predetermined time after a print command; a first control means for controlling the information output device so as to output the information to the support; a means for generating a second control signal after a predetermined period of time after starting output of image data from the information output device;
The present invention is characterized in that it has a second control means for controlling the above-mentioned feeding means to feed the transfer material in accordance with a control signal.

The present invention will be described in detail below with reference to the M plane.

FIG. 1 is a schematic diagram for explaining the operation of an embodiment using an electrophotographic method. A laser beam 2 oscillated by a laser oscillator 1 is modulated according to an input signal from an information output device 56 to a modulator 3, and then scanned by a rotating polygon mirror 4 onto a drum-shaped photoreceptor 7 rotating in the direction of the arrow. Nii B! exposed to light. Note that other means such as a cathode ray tube, a plasma display, etc. can also be used for optical image exposure.

Various electrophotographic processes that have been proposed in the past can be applied to the present invention. Detailed explanation of.

The photoreceptor 7 basically has a conductive support, a photoconductive layer, and an insulating layer on the surface, and is uniformly charged in advance by a second corona charger 8, and then subjected to optical image exposure by the laser beam. At the same time, AC corona discharge is performed by the AC corona discharger 9, and the entire surface of the photoreceptor 7 is uniformly exposed by the full-surface exposure lamp 10. As a result, an electrostatic latent image according to the light image described in "1" is formed on the photoreceptor. Formed on the surface of the body 7.

This electrostatic latent image is formed by charged colored particles (toner) in the developing device 11.
It is developed with a developer mainly consisting of , and is visualized. The developed image is transported by a fan, which is a transfer material, transported by a tractor 16 which has a sprocket bin that engages with a sprocket on the transfer material side, and a first intermediate transport device 22 which has a suction fan 32 and a perforated belt 31. Transfer roller 1 is placed on hold paper 15 (hereinafter also referred to as transfer paper or simply paper).
9.21 and the electric field from the transfer corona discharger 20 to perform the transfer.

When there is no more information recorded on the photoreceptor 7 and the last part of the image has been transferred to the transfer paper, the transfer rollers 19 and 21 are released and the corona discharge for transfer is stopped, and the transfer paper 1
5 separates from the photoreceptor 7, the tractor 16 begins to reverse direction. As a result, the transfer paper in the conveyance heald 31-1- is pulled by the suction fan 32 and tension is applied to move it forward, and the transfer paper 15 is peeled off from the surface of the photoreceptor. Further, at the same time, the reverse tension applied to the transfer paper due to the reverse rotation of the tractor 16 is stronger, so the transfer paper 15 is moved backward, and is stopped after being moved back enough to prevent misalignment and blurring when restarting. Thereafter, when low recording is performed on the photoreceptor 7 again, the developed image on the photoreceptor 7 and the transfer roller 19
・21 presses the transfer paper 15 against the photoreceptor 7 again, applies voltage to the transfer corona discharger 20, and develops the trailing edge of the previously transferred image on the paper 15'' and the photoreceptor 7. The developed image on the photoreceptor 7 is transferred and recorded onto the transfer paper 15 as a continuous image with the leading edge of the image being continuous, that is, without any deviation or blurring at the image joint.

FIG. 2 is an enlarged view of the transition portion. A first transfer roller 19 and a second transfer roller 2 whose surfaces are covered with insulating rubber.
Reference numeral 1 is located close to the transfer corona charger 20, and the image is blurred due to spread of corona charge, that is, toner scattering and image that occur when a transfer electric field due to corona charge is applied before or after separation of the paper and photoreceptor. In addition to preventing blurring, by pressing the transfer paper against the photoreceptor, it eliminates defects caused by the transfer paper lifting, especially when using fan-hold paper as the transfer paper, image transfer defects caused by lifting from the photosensitive plate at the perforations. , functions to perform stable and uniform transfer.

On the other hand, during non-transfer, the first transfer roller 19 and the second transfer roller 21 are released from the pressure contact of the transfer paper 15 against the photoreceptor 7 by the first plunger 29 and the second plunger 30, and are positioned as shown by the broken line in the figure.

Furthermore, at the same time, the upper guide plate 28 , which is built into the same substrate (not shown) as the first transfer roller 19 , moves in the direction of peeling off the transfer paper 15 from the photoreceptor 7 when the first plunger 29 is released. Ensures peeling.

FIG. 3 is a schematic diagram illustrating a mechanism for transporting and returning transfer paper. In FIG. 3, the photosensitive drum 7 is driven by a drive motor 33,
Pulley 40.41, timing belt (or chain)
44, and driven by gears 46 and 47,
Further, the drive motor 33 conveys the transfer paper 15 by means of pulleys 42, 43, a timing belt 45, a transfer paper conveyance clutch (for example, a micro powder clutch) 37, and a tractor 16. The transfer paper 15 is fed in synchronization with the photosensitive drum 7 by the action of a clutch 37 that is controlled based on a pulse signal emitted by a rotary encoder 35 (described later).
7 is released, the reversing clutch 38 is turned on, and the drive of the paper return motor 34 is transmitted through the gears 50, 51, 52, 53, the tractor 16 is reversed, and the transfer paper 15 is returned. When the transfer paper 15 has been returned a predetermined distance by the row encoder 36, the stop clutch 39 is activated and the transfer paper 15 is stopped. When information is recorded on the photoreceptor again, the conveyance latch 37 is activated by a signal from the low reencoder 35, and synchronized transfer paper conveyance is resumed.

In FIG. 3, the conveyance and return by the tractor 16 when the transfer paper 15 is a fan-hold paper has been explained, but the tractor may be carried out by a pair of rollers, and if the transfer paper is a roll paper, the transport and return are explained. It is effective for

On the other hand, after the transfer is completed, the colored particles (toner) remaining on the photosensitive drum are removed by a cleaning device 12 in preparation for the next electrostatic latent image forming process.

The transfer paper that has passed through the transfer process is sent to a first intermediate conveyance device 22, a buffer device 23, a second intermediate conveyance device 24, and a heat roller type fixing device 25. The speed of the transfer paper up to the first intermediate conveyance device 22 is 1. The operation of the feed tractor 16 is completely synchronized with the movement of the photoreceptor. On the other hand, due to thermal changes in the diameter of the fixing roller,
The speed of the transfer paper passing through the fixing device due to the meandering correction operation of the transfer paper is slightly different from the paper feeding speed of the paper feed tractor 16. Minute errors accumulate, causing inconveniences such as the transfer paper being cut or being stuck in the middle of the idle feeding system.Buffer device 23
, the slack in the transfer paper is detected, and when the slack becomes larger than the specified value, the rotation i1 degree of the fixing roller is set lx
The above-mentioned disadvantages are solved by controlling the rotational speed of the fixing roller to be lowered when the slack becomes smaller than a specified value. In addition, in the fixing device, the transfer paper is
It is transported by two rollers while being protected from heat and pressure. At this time, the transfer paper is slightly skewed due to a slight difference in the balance of the pressure in the direction of the rotation axis, a difference in the diameter of the roller in the direction of the rotation axis, an unbalance between left and right expansion and contraction of the transfer paper, and the like. In the case of long continuous paper, minute amounts of skew are accumulated and become an impossible value. In the second intermediate conveyance device 24, the skew of the transfer paper is detected and corrected by changing the suction amount of the suction device and controlling the left and right balance of the pack tension, thereby causing the skew to accumulate. to prevent

FIG. 4 shows the fixing device in detail.

The transfer paper 15 having the transferred powder image on its surface is fixed and conveyed while being applied with heat and pressure by a fixing roller 61 and a pressure roller 64. The paper discharge rollers 77 and 78 always apply tension to the transfer paper 15 with a constant torque. The heating rollers 62 and 63 rotate while contacting the fixing roller 61 and apply heat to the fixing roller. Rotational drive is applied only to the fixing roller 61 by a drive motor (not shown). The heating rollers 62 and 63 and the pressure roller 64 follow the fixing roller. The fixing roller 61 is constructed by adhering heat-resistant thick releasable rubber (such as room temperature vulcanizable silicone rubber) to the surface of a metal cylinder.

The pressure roller 64 is constructed by adhering a thin heat-resistant elastic body to the surface of a metal cylinder. The heating rollers 62, 63 contain infrared rays and rays 79, 80 inside an aluminum cylinder whose surface is plated with chrome.

When the transfer paper 15 is not running, the pressure roller 64 is apart from the fixing roller 61, and the transfer paper is also
It is separated from the fixing roller 61. Further, the auxiliary heater 63 is also separated from the fixing roller 61. heating roller 62
contacts the fixing roller 61 and rotates together, applying heat to the surface of the fixing roller. The temperature on the surface of the heating roller 62 is detected by the thermistor 72, and the power applied to the heater 79 is controlled to keep the surface temperature constant.
The surface temperature of 1 is kept constant. In addition, the fixing roller 61
The surface temperature of the auxiliary heating roller 63 that is not in contact with the auxiliary heating roller 63 is similarly maintained at a constant value. These temperature controls are performed by a temperature control circuit 74 in a known manner.

The fixing operation is started as follows. First, the rotation of the fixing roller 61 is stopped, and then the pressure roller 64 is pressed against the fixing roller 61 via the arm 69 by the operation of the air cylinder 68.

Therefore, the transfer paper 15 is also pressed against the fixing roller. When the pressing operation is completed, the fixing roller stops rotating. At the same time, the auxiliary heating roller 63 is brought into contact with the fixing roller 61 by the force of the air cylinder 66 via the arm 65. This is done by the transfer paper 15 due to the fixing operation.
The heat carried away is supplied to the surface of the fixing roller 61 to maintain the surface temperature constant.

The fixing operation is completed in the following order. Fixing roller 61
After the rotation of the fixing roller 61 is stopped, the auxiliary heating roller 63 is separated from the surface of the fixing roller 61 by the operation of the air cylinder 66, and the pressure roller 64 is further separated from the fixing roller 61 by the operation of the air cylinder 68. At the same time, the separation piece 75 moves the transfer paper 15 to the fixing roller 6 by the operation of the solenoid 76.
It acts as if knocking it off the surface of 1. The transfer paper is subjected to back tension by the second intermediate conveyance section and ) JP 1. B
Due to the tension exerted by the roller 7778, it comes to the position shown by the dashed line. When the transfer paper is separated, the fixing roller 61 starts rotating again. Thus, the waiting state νζ is returned.

Through the series of operations described above, even when the transfer paper runs intermittently, complete fixing is performed without causing problems such as undefined magnification areas, image shift, and scorching of the transfer paper. Power,
Air is sent from the compressor 71 to the air cylinders 66, 68 via electromagnetic valves 69, 70. The operation of the air cylinder 66.6B is controlled by the solenoid valve 69.70.
One step is to switch between a state in which air is sent into the air cylinder and a state in which air in the air cylinder is released.

Front) Book light 11: The sequences of exposure, latent image formation, development, transfer, and fixing, and the timing control of the driving section necessary therefor, are performed by a control circuit 57 (FIG. 11).

FIG. 5 shows a timing chart for explaining the relationship between the main print signals and the operation of the drive section. First, the power is turned on to the apparatus, and steps such as preheating the fixing device and loading the transfer paper into a predetermined position are completed. Here, the information output device 56 in FIG. 1 is an output device of a computer. When the information to be recorded is prepared, the PRI is sent to the control circuit 57 on the recording device side.
It sends NT signals. In response to the PRINT signal, the control circuit 57 applies power to the motor that rotates the photosensitive drum.

At the same time, each charger except the transfer charger 20, the developer, the cleaning device, and the lamps start operating to prepare for latent image formation (pre-rotation).

When the pre-rotation is completed (dA), a DATA READY signal (first control signal) is sent from the control circuit 57 to the information output device 56 . The information output device 56 is a DATA
If the READY signal is "1", data transfer is started. During data transfer, the DATA signal is 1'', and at the same time a necessary modulation signal is sent to the modulator 3.

At the same time as the DATA signal goes low, the exposure position (the top of the ACC charger 9) where the beginning of the information to be recorded (Fig. 1) is exposed, becomes a high contrast electrostatic latent image, is developed and transferred. When the transfer paper reaches the position, it contacts the photosensitive drum and starts running at the same speed as the circumferential speed of the photosensitive drum, and at the same time voltage is applied to the transfer charger. As long as the start of movement to the contact position and the start of transfer corona generation are sufficiently short, dB = dC = dD - the time it takes for the photosensitive drum 7 to rotate from the exposure position to the transfer position.However, these The practical value of the rising time (several m8 to 1.00 m
dB (second control a) in consideration of these rising times in order to allow a
11 signals), dC, and dD are determined.

These relationships will be explained with reference to FIG.

As mentioned above, in order for the transfer to be performed perfectly, it is necessary that the speeds of the optical drum and the transfer J are the same, that the transfer paper and the transfer drum are in contact with each other, and that It is necessary that the strength of the transfer corona is sufficient, and in order to prevent the toner image from scattering, the transfer corona must not be applied to 1) 1j until the transfer paper comes into contact with the optical drum.

To add this condition to 1, first, the speed of the rolling paper (
It is sufficient to keep the speed of the tractor constant, then bring the transfer paper into contact with the photosensitive drum, and then remove the transfer corona. This series of operations inevitably results in blank areas that cannot be transferred onto the paper. In order to minimize this blank space, dB and dCldD are determined as shown in FIG. In this way,
The non-transferable area can be minimized by giving optimal timing to energize the transfer paper feeding means, transfer paper pressure contact means, and transfer electric field application means, taking into account the startup time of each of them. can. - Similarly, at the end of the transfer, the timing dB, di for releasing the energization is determined by taking into account the falling time of each of the above means.
, dJ are determined (Figure 7). Rise and fall times: Tractoria ~ 10m5, Transfer roller: 30~40m5
.

When the transfer corona was set to 80 to 100 ms, the blank space at the start and end of transfer could be kept within 1/2 inch at a peripheral speed of the photosensitive drum of 2000 inches/minute. Furthermore, in order to make the blank area smaller or zero, the transfer paper is moved back by the amount of the blank area when the transfer is completed, as described above.

Furthermore, if the transfer paper is fed intermittently even when the fuser is blown, a series of operations will be performed according to the sequence described above in order to complete the fixing. If the rise time and fall time of stopping, pressurizing the pressure roller, and releasing the pressure roller are not taken into account, the difference in conveyance of the transfer paper between the tractor and the fixing device will exceed the tolerance absorbed by the buffer device 23, and the transfer paper will be Something like a break occurs. FIG. 8 shows a preferable relationship between the movements of each element in the fixing device when the transfer is started, and FIG. 9 shows the movement when the transfer ends.

In this way, a series of recording operations is completed, and PRINT (, i becomes 0'' from the information output device. However, the control circuit maintains the printable state for a while (dO) and outputs DATA. The READY signal is set to 1". If the PRINT signal becomes 1" again during this period, information can be written immediately without requiring the pre-rotation time (dA).Even if the period of dO is exceeded, 1'RI
If the NT signal does not become 1", a sequence for stopping the photosensitive drum is performed (dP), and the photosensitive drum stops +LL and returns to the initial waiting state. dB, dC, dD. as shown in FIG. , dE, dF.

dG predetermines the pulses of the low reencoder 35, which generates the number of pulses proportional to the rotation of the photosensitive drum connected to the rotation shaft of the photosensitive drum, based on the rise of the DATA signal from 00'' to 11''. By counting the number of digits, it can be given with high accuracy. Similarly, dH
ldi, dJldKldM.

Similarly, dN is given by counting a fixed number of pulses from the rotary encoder 35 with reference to the fall of the DATA signal from 1'' to 0. Fig. 10 shows these counting circuits, and Fig. 11 shows these counting circuits. 2 shows an embodiment of a circuit for generating drive signals for each of the above-mentioned means.

The rotary encoder 35 (FIG. 3) generates a series of pulses by photoelectrically detecting holes in multiple discs provided on the rotating shaft of the photosensitive tram.

A repeating pulse is generated by the rotation of the photosensitive drum via a low-resolution encoder 101 and is input to a gate circuit 102 . The pulse passing through the gate 102 is sent to the counter 104.
and counted. Since the photoreceptor is endless, there is no need to apply a gate depending on the drum position. Setting devices 107 and 109 that set this count value and each drive machine timing
Comparators 106 and 108 determine whether the

When it wants, it generates coincidence pulses dBC, dI(C).

103 gates the pulse when the counter reaches the maximum value 10
2 and close the gate [It is a moving object, 103
The necessity of the 0 circuit is because, for example, when the counter is a 2-digit total, the drum pulse reaches 99, returns to 0, and starts counting 4 again, so the coincidence pulse may occur many times during the same mode. This is to prevent this. 110 is “PRINT” and “DATA” sent from the information output device 5G.
The print mode signal CMO1C as shown in Fig. 5 is generated by the signal.
This print mode generation circuit generates MI, CM2, data rising signal TRA1, and data falling signal TRB. This circuit is composed of two human input signal feeding gates, and a well-known circuit for detecting the leading and trailing ends of the signal DATA. For example, DataRea
Assuming that the time from the rise of the dy signal until the data is sent out is approximately the same, this can also be shown in FIG. FIG. 13 shows an example of 120 in FIG. 12. 105 is an OR circuit and TRA.

The counter 104 is reset by TRB and the gate 102
Open.

Next, the operation sequence of the tractor (in order) for paper feeding will be explained using an example (FIG. 11). As mentioned above (PRINT
When a signal is sent and the drum rotates, a drum pulse is sent from the low encoder.

After DATA READY lights up r) When the ATA signal is sent, a TRA pulse is sent from the mode generator 110, clears the counter 104, opens the gate 102, and generates the mode signal CMI. When the count value of the counter 104 matches the 1070 dB value of the setter, the comparator 106 sends a dBC pulse. JK flip-flop 113 is set when dBC and CMI match.

When the counter 104 reaches the maximum value, a coincidence pulse is generated from the counter 103, the gate 102 is closed, and the counter 104 stops advancing.

DATA (retain this state until 'fi disappears,
When the DATA signal disappears, the TRB signal is output and the counter 10
4 and open the gate 102. On the other hand mode occurrence 3
A mode signal CM2 is output from 2110. counter 10
4 advances and when it matches the set value dH of 109, a -2 change output dHC is output. This results in dHC.

When CM2 matches, the JK flip 70 knob 113 is turned on, the tractor drive signal disappears, and feeding is stopped.

Similarly, when the r) ATA signal is generated again, a tractor drive signal is generated with a delay of dB to start feeding, and the tractor drive signal disappears with a delay of dII. Signals for each drive machine other than the truck will be similarly explained.

As described above, in the present invention, since data is output by the first control signal output after the pre-rotation of the support for a predetermined period of time, an image can be formed on the support surface that has been sufficiently prepared for image formation, and the data output can be started. Since the transfer material is fed by the second control signal outputted after a predetermined time, there is no possibility that the image formed on the support and the transfer material will be misaligned. Therefore, high quality recorded matter can be obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an example of the recording apparatus of the present invention, FIG. 2 is a sectional view of the transfer section in FIG. 1, FIG. 3 is a schematic diagram of the transfer material feeding drive section, and FIG. 4 is a fixing device. 5 is a time chart of the recording apparatus according to the present invention, FIG. 6.7 is a characteristic diagram of the transfer element at the start and end of transfer, and FIG. 8.9 is a diagram showing the start of fixing.
Characteristic diagram of the anchoring element at the end, No. 10.11.12.13
The figure shows the first cycle for forming control signals. In figure 1, 7 is a photosensitive drum, 15 is a rolling paper, 16 is a tractor, and
0 is a transfer charger, 25 is a fixing roller, and 35 is a rotary encoder. Applicant Canon Co., Ltd.

Claims (1)

[Claims] In a recording apparatus having an image support, a means for forming an image on the support, and a feeding means for feeding a transfer material to transfer the image formed on the support onto a transfer material, the image forming means an information output device that outputs image data to the image data;
means for generating a first control signal after rotation of the support for a predetermined time after a print command; and controlling the information output device to output the image data to the work support using the first control signal. After a predetermined period of time has elapsed from the start of output of image data from the first control means and the L=+71 report output device, the second system is activated.
A recording apparatus comprising: means for generating a signal; and second control means for controlling the feeding means to feed the transfer material using the second control signal.