JPH01145678A - Transferring and releasing device for transfer material - Google Patents

Abstract

PURPOSE:To easily release a transfer material from a photosensitive body by specifying the absolute value of a voltage for a transfer corotron which is set by a 1st voltage setting means and the absolute value of a voltage for a separating corotron. CONSTITUTION:This device is provided with the 1st voltage setting means 20 which sets the values of voltages applied to the corotrons 6 and 7 while the periphery of the tip part of the transfer material 14 passes between the transfer corotron 6 and separating corotron 7, a 2nd voltage setting means 21 which sets the values of voltages applied to the two corotrons 6 and 7 while the remaining part of the transfer material passes between the transfer corotron 6 and separating corotron 7, and a voltage switching means 22 which switches the two voltage setting means 20 and 21 at preset timing. Then the circumference of the tip part of the transfer material 14 is set lower in voltage applied to the transfer corotron 6 than other part of the transfer material 14 to increase the voltage applied to the separating corotron 7. Therefore, corona discharge generated by the separating corotron 7 is increased at the tip part of the transfer material which is hard to separate from the photosensitive body. Consequently, the transfer material 14 is easily released from the photosensitive body.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device for transferring and peeling off a transfer material in an image recording apparatus, and in particular controls the output of a transfer corotron and a peeling corotron to The present invention relates to a transfer and peeling device for a transfer material, which allows the transfer material to be easily peeled off from a body.

(Prior Art) FIG. 4 shows an example of a conventional transfer device in an electrophotographic copying apparatus.

Generally, an electrophotographic copying apparatus has a transfer device as shown in FIG. In the center of the transfer device, a cylindrical photoreceptor 1 having a photoreceptor layer is arranged rotatably in the direction of an arrow 12.

Around the photoreceptor 1, a charger 2. LED head 3.
Developing device 4. Shoot 5. Transfer corotron 6, peeling corotron 7, peeling claw 8. The cleaner 9° static elimination lamps 10 are arranged counterclockwise in the stated order.

The transfer device having the above configuration performs the following operations.

First, the surface of the photoreceptor 1 is charged to a uniform potential by the charger 2. Then, on the charged photoreceptor 1,
By projecting an image with the LED head 3, an electrostatic latent image corresponding to the image is formed.

Next, the electrostatic latent image is converted into a toner image and developed by a developing device 4. The toner image is transferred onto the transfer material 14 conveyed from the chute 5 by the action of corona discharge, which is generated from the transfer corotron 6 and has an electric charge opposite in polarity to that of the toner.

A corona discharge having the same polarity as the photoreceptor 1 is generated from the peeling corotron 7 adjacent to the transfer corotron 6, and the transfer material 14 that is in close contact with the surface of the photoreceptor 1 is peeled off by the action of the corona discharge. .

The portion of the transfer material 14 that has not been peeled off from the photoreceptor 1 is
Furthermore, it is mechanically peeled off by a peeling claw 8 and discharged to a fixing device (not shown). Finally, after the toner image is transferred, the toner image remaining on the surface of the photoconductor 1 is removed by a cleaner 9, and the charge on the surface of the photoconductor 1 is neutralized by the neutralization lamp 10, and the transfer process is completed. .

As described above, generally, a toner image is transferred from the photoreceptor 1 to the transfer material 14 by the action of corona discharge generated by the transfer corotron 6, and the transfer material 14 is transferred to the transfer material 14 by the peeling corotron 7.
The photoreceptor 1 is peeled off from the surface of the photoreceptor 1 by the action of corona discharge generated in the process.

(Problems to be Solved by the Invention) The above-described conventional techniques had the following problems.

A constant high voltage (the polarity is determined by the polarity of the toner) is applied from a high voltage power source to the transfer corotron 6 and the peeling corotron 7, and a corona discharge is generated.

By the way, various materials such as plain paper, tracing paper, film sheet, etc. are used for the transfer material 14, and the thickness thereof also varies. Also, the ambient temperature at the time of copying.

Changes in humidity may also be considered.

Therefore, if the voltage applied to the transfer corotron 6 and the peeling corotron 7 is constant, it is not possible to obtain a sufficient peeling effect in response to the various materials and changes in the usage environment as described above. Sometimes.

If the peeling effect is not sufficient, the transfer material that is difficult to peel off will not be smoothly discharged from the transfer device, causing problems such as the transfer material becoming clogged in the transfer device.

The present invention has been made to solve the above-mentioned problems.

(Means and effects for solving the problem) In order to solve the above problem, the present invention provides that the vicinity of the leading end of the transfer material is
a first voltage setting means that sets a voltage value to be applied to each corotron while the remaining portion of the transfer material passes through the transfer corotron and the peeling corotron; The present invention is characterized in that it includes a second voltage setting means that sets a voltage value to be applied to each of the two corotrons, and a voltage switching means that switches between the two voltage setting means at a preset timing.

In the present invention having the above configuration, the voltage applied to the transfer corotron is lower near the leading end of the transfer material, and the voltage applied to the peeling corotron is higher, compared to other parts of the transfer material. ing.

Therefore, the corona discharge generated from the peeling corotron can be strengthened at the leading edge of the transfer material, which is difficult to peel off from the photoreceptor, so that the transfer material can be easily peeled off from the photoreceptor.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention.

17 is a control circuit consisting of a microcomputer, etc., and its functions are represented by a functional block diagram.

In the figure, the transfer material 14 is connected to a register roll 15,
As the presser roll 16 rotates, the photosensitive member 1 is conveyed through the chute 5 toward the photoreceptor 1 .

The register roll 15 is connected to a clutch 13, and starting and stopping of the clutch 13 is controlled by an on/off signal output from a register roll driving means 18.

That is, while the ON signal is output from the register roll driving means 18, the register roll 15 is rotated and the transfer material 14 is conveyed.

The ON signal from the register roll driving means 18 is also input to the first delay timer 23, and after the time set in the first delay timer 23 has elapsed, a time-up signal is output to the voltage switching means 22, and the time-up signal is outputted to the voltage switching means 22. A switching operation of the voltage switching means 22 is performed.

By the switching operation of the voltage switching means 22, switching from the first voltage setting means 20 to the second voltage setting means 21 is performed, and the voltage value set to the high voltage power supply 11 is changed to the setting value of the first voltage setting means 20. The voltage is then switched to the setting value of the second voltage setting means 21.

Further, the off signal of the register roll driving means 18 is the second one.
After the time input to the delay timer 24 and set in the second delay timer 24 has elapsed, the time-up signal of the second delay timer 24 is output to the voltage switching means 22,
The voltage switching means 22 is reset by the signal, and the voltage value set to the high voltage power supply 11 is changed to the second voltage setting means 21.
The voltage is switched from the value set in the first voltage setting means 20 to the value set in the first voltage setting means 20.

In this way, in response to the ON signal from the register roll drive means 18, a voltage of the value set in the first voltage setting means 20 is applied from the high voltage power supply 11 to the transfer corotron 6 and the peeling corotron 7.

The value of the voltage applied to each corotron from the high voltage power supply 11 is held at the value set in the first voltage setting means 20 until the first delay timer 23 times up. After the timer 23 times up, the pressure is switched to the value set in the second N & pressure setting means 21.

Then, the off signal of the register roll drive means 18 is output to the second delay timer 24, and after the time set in the second delay timer 24 has elapsed, the off signal is applied from the high voltage power supply 11 to the transfer corotron 6 and the peeling corotron 7. The voltage value set is again switched to the value set in the first voltage setting means 20.

That is, the transfer corotron 6 and the peeling corotron 7
The timing of switching the voltage value applied to is determined by the set values of the first delay timer 23 and the second delay timer 24.

The operation of one embodiment of the present invention having the above configuration will be explained with reference to the flowchart shown in FIG.

In the figure, first, when the control circuit receives a start signal, in step S1, the register roll driving means 1
8 is outputting an on signal.

If the register roll driving means 18 does not output an on signal, the process moves to step S8, and the voltage switching means 22
As a result, the value output from the high-voltage power supply 11 is set as the setting value of the first voltage setting means 20, and the process returns to step S1 again.

If the register roll driving means 18 is outputting an on signal and the determination in step S1 is affirmative, the process advances to step S2.

In step S2, the first delay timer 23 operates, and while the first delay timer 23 is operating, the voltages applied to the transfer corotron 6 and the peeling corotron 7 are as follows.
The value set in the first voltage setting means 20 is held.

When the first delay timer 23 times up (step S3), the transfer corotron 6,
The voltage applied to the peeling corotron 7 is changed by the voltage switching means 22 from the voltage value set in the first voltage setting means 20 to the second voltage setting means 21 . The voltage value can be changed to the voltage value set in .

After the voltage value is switched in step S4, it is determined in step S5 whether or not the register roll driving means 18 is stopped.

When the register roll driving means 18 is stopped, the judgment in step S5 becomes affirmative, and the process proceeds to step S6, where the second
Delay timer 24 operates.

The second delay timer 24 times up (step S7
), the process proceeds to step S8, and the value of the voltage applied from the high voltage power supply 11 to the transfer corotron 6 and the peeling corotron 7 is changed from the setting value of the second voltage setting means 21 to the value of the first voltage setting means 20. The setting value can be changed.

Next, the switching timing of the voltages applied to the transfer corotron 6 and the peeling corotron 7, the on/off signals of the register roll driving means 18, and the positional relationship with the transfer material 14 will be explained with reference to FIG.

In the figure, the vertical axis represents the DC applied voltage when the AC component is constant, and the horizontal axis represents the elapsed time.

In the figure and in the following explanation, the numerical values appended to the symbols of the curves representing changes in voltage value are examples of the voltage value of the DC power supply when the AC component is constant.

Note that since the polarity of the applied voltage is determined by the polarity of the toner, only the absolute value of the voltage is expressed here.

After the ON signal of the register roll driving means 18 is output at 8 points and the set time DT of the first delay timer 23 has elapsed, the voltage setting value changes from the setting value of the first voltage setting means 20 at the 0 point. , is switched to the setting value of the second voltage setting means 21.

When the setting value is switched, the high voltage value TCH set in the second voltage setting means 20 is applied to the transfer corotron 6, and the second voltage setting means 2 is applied to the peeling corotron 7.
A low voltage value DTCL, which is set to 0, is applied.

At point R, an off signal is output from the register roll driving means 18, and after the time dT set in the second delay timer 24 has elapsed, at point E, the transfer corotron 6 is turned off.
The voltage applied to the peeling corotron 7 is switched to a low voltage value TCL, which is set in the first voltage setting means 21, and the voltage applied to the peeling corotron 7 is set in the 1'B1 pressure setting means 20. , is switched to a higher voltage value DTCH.

That is, the value of the voltage applied to the transfer corotron 6 and the peeling corotron 7 in the range from the tip of the transfer material 14 is the value set in the first voltage setting means 20. The part after removing the part is
The value of the voltage applied while passing through the transfer corotron 6 and the peeling corotron 7 is determined by the second voltage setting means 21.
This is the value set to .

As a result of the inventor's experiments, the above range is 20 mm to 80 mm.
By setting the first delay timer 23 so that the time is 100 seconds, the transfer material 14 could be reliably peeled off from the photoreceptor 1.

The set value of the second delay timer 24 is longer than the time it takes for the rear end of the transfer material 14 to pass through the peeling corotron 7 after the off signal is output from the register roll drive means 18. It is sufficient to set a time shorter than the interval between when an off signal is outputted and when an on signal is outputted next.

In addition, when the output of each corotron is a superimposed DC component and AC component, either one of the DC component and the AC component, or both the DC component and the AC component may be switched. . Moreover, in the case of only the DC component, only the DC component is changed. In this embodiment, the first delay timer 23 and the second delay timer 2
An example has been described in which a signal for operating the register roll driving means 18 or for turning on the power supply opening/closing means 19 is obtained from the on/off state of the register roll driving means 18.

However, the signal is not limited to an on/off signal of the register roll driving means 18, and is not limited to an on/off signal of the register roll driving means 18, but a sensor that detects that the transfer material 14 has passed through the chute 5, for example, in the middle of the path from the register roll 15 to the photoreceptor 1. is provided, and the power supply opening/closing means 19. is operated by the on/off signal of the sensor. First delay timer 23. The second delay timer 24 may also be controlled.

According to this embodiment, as is clear from the above description, the voltage applied to the transfer corotron is lowered near the tip of the transfer material to suppress the output of the corona discharge generated from the transfer corotron, and conversely, By increasing the voltage applied to the peeling corotron and increasing the output of the corona discharge generated from the peeling corotron, static electricity accumulated on the transfer material is weakened, and the transfer material is easily peeled off from the photoreceptor.

(Effects of the Invention) As is clear from the above description, according to the present invention, the problem that the transfer material adheres closely to the photoreceptor and does not peel off after the transfer of the toner image is completed, and therefore, the transfer material The transfer material does not become clogged in the transfer device due to the material not peeling off.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram of an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of an embodiment of the present invention, and FIG.
The figure is a diagram showing the relationship between the position of the transfer material and the voltage of the DC component when the AC components of the transfer corotron and the peeling corotron are constant, and FIG. 4 is a diagram showing an example of a transfer device in an electrophotographic copying apparatus. DESCRIPTION OF SYMBOLS 1... Photoreceptor, 5... Chute, 6... Transfer corotron, 7... Peeling corotron, 11... High voltage power supply, 13... Clutch, 14... Transfer material, 15...・
Register roll, 18... register roll driving means,
20... First voltage setting means, 21... Second voltage setting means, 22... Voltage switching means, 23... First delay timer, 24... Second delay timer agent Patent attorney Hiraki 1 person outside of the connoisseur! 2 Figure

Claims (3)

[Claims] (1) In a transfer material transfer and peeling apparatus having a high voltage power source that applies high voltage to a transfer corotron and a peeling corotron, a first voltage setting means sets a first voltage value to the high voltage power source; a second voltage setting means for setting the second voltage value; a voltage switching means for setting one of the voltage values set in the first and second voltage setting means to the high voltage power supply; After detecting a signal indicating the start of conveyance of the transfer material toward the transfer corotron and the peeling corotron, the voltage switching means is operated after a predetermined time delay to change the voltage value from the first voltage value to the second voltage value. a delay timer for switching, the absolute value of the transfer corotron voltage set in the first voltage setting means is lower than the absolute value of the transfer corotron voltage set in the second voltage setting means; An apparatus for transferring and peeling a transfer material, characterized in that the absolute value of the peeling corotron voltage set in the first voltage setting means is higher than the absolute value of the peeling corotron voltage set in the second voltage setting means. (2) The signal indicating the start of conveyance of the transfer material is obtained from an ON signal of a register roll driving means that outputs a drive signal to a register roll provided for conveying the transfer material. A transfer material transfer and peeling device according to claim 1. (3) A signal indicating that conveyance of the transfer material has started is obtained from a signal that detects that the leading edge of the transfer material has passed through a sensor provided on a chute for conveying the transfer material. A transfer material transfer and peeling device according to claim 1.