JPH0141507B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic recording device that performs electrostatic recording by solid-state scanning using a charged particle flow modulation electrode.

An electrostatic recording device is a device that records on recording paper information output from a computer, information transmitted through a communication line, or an image signal of information obtained by converting a document image into an electrical signal using a solid-state image sensor such as a CCD. There are various types currently being proposed. In an electrostatic recording device, an electrostatic latent image corresponding to an image signal is formed on a charge carrier such as a photoreceptor, dielectric material, or recording paper. There is a type of electrostatic recording device that forms an electrostatic latent image on a dielectric material using an ion modulation electrode that modulates generated corona ions in accordance with an image signal. Figure 1 shows a schematic configuration of an example of this type of electrostatic recording device, in which an image signal obtained by photoelectrically converting an original image using a solid-state image sensor such as a CCD, and an electrical information signal from a computer or communication line are used. The signal is supplied to a signal processing circuit 1, processed there, and then supplied to an ion flow modulation electrode drive circuit 2. Reference numeral 3 denotes a control circuit including a clock generator that provides timing for outputting signals from the signal processing circuit 1 and the drive circuit 2.
The ion flow modulation electrode 4 has an insulating layer sandwiched between a common electrode 4a and a control electrode 4b, and has a plurality of ion passage holes 4c formed in one or more rows.
An image signal is given to b from the drive circuit 2. A corona wire 5a is placed above the ion flow modulation electrode 4.
A corona ion generator 5 incorporating a corona ion generator 5 is disposed, and a dielectric rotating drum 6 is disposed below the ion flow modulating electrode 4. Dielectric rotating drum 6
A developing device 7, a transfer electrode 8, a separation claw 9, a static elimination electrode 10, a developer scraping plate 11, etc. necessary for normal electrophotographic processing are arranged around the , and a fixing device 12 is further provided. . The amount of ions generated by the corona ion generator 5 passing through the ion passage hole 4c is controlled by the control signal applied to the control electrode 4b of the ion flow modulating electrode 4, so that the ions are recorded on the dielectric material of the rotating drum 6. An electrostatic latent image corresponding to the desired image information is formed. The electrostatic latent image thus formed is transferred onto the recording paper P by a transfer electrode developed with a developer in the developing device 7. Thereafter, the recording paper 4 is separated from the dielectric rotating drum 6 by a separating claw 9, fixed by a fixing device 12, and discharged from the apparatus.

By the way, the ion flow modulating electrode used in the electrostatic recording device has a large number of ion passing holes 4c formed in one or more rows, and the amount of ions passing through each passing hole 4c is determined by the common electrode 4a and the control electrode. 4
It is controlled by the voltage applied to b. Therefore, the control electrode 4b is independent for each passage hole, and is supplied with an image signal from the drive circuit 2. but,
Since the number of passage holes 4c is as large as, for example, 5 to 15 per mm, the number of wirings to the control electrodes corresponding to each passage hole 4c is enormous. If you try to increase the recording resolution, the number of wires will increase. Therefore, as shown in Fig. 2, all the passage holes and all the corresponding control electrodes are divided into a plurality of (for example, 15 to 16) groups G ₁ to G _o , and the control electrodes (for example, group G Control electrode 4 _{of b1 C e1} and control electrode 4 of group G ₂ C _e2 of _b2 ... Control electrode ₄ of group G _o
C _eo ) of _o ) are wired in common so that the same image signal is given at the same time, and the recording operation group (the group that controls the ion flow according to the electric image signal) is connected to the common electrodes 4 _a1 , 4
_a2 ...4 The number of wires can be reduced by controlling by the voltage applied to _ao (in this case,
The common electrode 4a is arranged facing the corona ion generator 5 as shown in FIG. ). This control method is known as a group control method or solid state scanning method. The group control method is advantageous because the configuration and capacity of the switching circuit, hold circuit, shift register, etc. that constitute the drive circuit that outputs the image signal to the control electrodes can be small.

However, in the electrostatic recording device using the group control method described above, the common electrodes 4 _a1 , 4 _a2 . . . of each group G ₁ , _{G 2} .
4 _ao and the control electrodes 4 _b1 , 4 _b2 , . . . , 4 _bo are divided at the same position, so there is a problem that the image density becomes non-uniform at the boundary between the electrodes. This will be explained with reference to FIG. FIG. 3 schematically shows the vicinity of the boundary between the two groups _G1 and _G2 of the divided ion flow modulating electrodes, and in this example, the common electrodes 4 _a1 and 4 _a2
In group _G1 , the passage of the ion current (positive ions) is blocked regardless of the voltage applied to the control electrode _4b1 , and in group _G2 , the passage of the ion current is controlled by the control electrode _4b2 . In such group control using positive ions, a common electrode 4 that allows the ion flow to pass through is used.
Since the potential of _a2 is higher than the potential of the common electrode _4a1 that blocks the passage of ion flow, some of the positive ions generated by the corona wire 5a in the region of group _G2 are transferred to the lower potential side as shown by the broken line. There is a tendency toward the common electrode _4a1 . Although not shown, group G ₂ and group G ₃
A similar phenomenon may occur at the boundary between
Therefore, at the boundary between each group, the ion flow passing through the ion passing hole 4c decreases, and the amount of charge held in the charge carrier decreases, resulting in a lower density of the recorded image and uneven image quality. be.

In view of the above points, the present invention divides the common electrode and control electrode of the charged particle flow modulation electrode into a plurality of groups in the arrangement direction of the charged particle flow passage holes, and each of the common electrode groups is connected to each opposing control electrode group. The same potential is applied to two adjacent common electrode groups corresponding to the control electrode group through which the charged particle flow should be allowed to pass.

The present invention will be explained below with reference to the drawings.

FIG. 4 shows the electrode arrangement of the charged particle flow modulating electrode of the electrostatic recording device according to the present invention, and shows the control electrode 4.
b is divided into n groups, and the common electrode 4a is (n+
1) It is divided into two groups, and both electrode groups are divided into two adjacent groups.
The two common electrodes, for example, 4 _a1 and 4 _a2 , are arranged so that the boundary between them is located at the center of the control electrode, for example, 4 _b1 . The drive circuit for the control electrode 4b includes a drive circuit 21 that drives the control electrode groups 4 _b1 , 4 _b3 , 4 _b5 .
The drive circuit 22 drives the control electrode groups 4 _b2 , 4 _b4 , 4 _b6 . . . These drive circuits 21 and 22 are supplied with an image signal from the signal processing circuit 1 (see FIG. 1), and are also supplied with a synchronization signal from the control circuit 3. This synchronization signal is also given to the drive circuit 23 of the common electrode 4a.

Next, signal application and operation to the ion flow modulation electrode configured as described above will be explained.

Now, in Fig. 4, in order to pass the positive ion flow only in the region of the control electrode group 4 _b2 , a high potential is applied to the common electrode groups 4 _a2 and 4 _a3 , and the image signal is applied to the other common electrode groups. A potential lower than that of the control electrode of the corresponding potential is applied. As a result, as shown in Figure 5,
The ion current (positive ions) is allowed to pass through the passage hole in the region of the control electrode group _4b2 without being deflected even at the boundary, as in the central region. But in this case,
Control electrodes 4 _b1 and 4 _b located on both sides of control electrode 4 _b2
Since the ion current tends to pass through the region ₃ as well, the drive circuit 21 is connected to both control electrodes 4 _b1 and 4 _b3 .
A potential is applied to prevent ions from passing through.

In this way, the amount of ion flow passing through the region of the control electrode group 4 _b2 becomes uniform, so that the concentration becomes uniform. Next, when the ion flow is caused to pass through the control electrode group 4 _b3 , a high potential is applied to the common electrode groups 4 _a3 and 4 _a4 , and a low potential is applied to the other common electrode groups. In this way, by scanning by sequentially switching the common electrode group, an electrostatic charge image corresponding to the image signal on the charge carrier is formed.

As explained above, in the present invention, the common electrode and control electrode of the charged particle flow modulation electrode are divided into a plurality of groups in the arrangement direction of the charged particle flow passage holes, and each of the common electrode groups divided in this way is Since the same potential is applied to two adjacent common electrode groups facing the control electrode groups which are arranged to be offset from each other to allow passage of the charged particle flow, In the region of each control electrode group, the amount of charged particle flow passing through becomes uniform, and the concentration becomes uniform. It goes without saying that the electrostatic recording apparatus according to the present invention has the advantage of group control. In the above embodiment, an ion flow was explained as a charged particle flow.
It goes without saying that charged ink mist or the like can also be used as a charged particle stream.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of an electrostatic recording device using an ion flow modulation electrode, Figure 2 is a schematic diagram showing the electrode configuration of a conventional ion flow modulation electrode, and Figure 3 is the operation of a conventional ion flow modulation electrode. FIG. 4 is a schematic diagram showing the electrode configuration of the ion current modulation electrode of the electrostatic recording device according to the present invention, and FIG. 5 is an explanatory diagram of the operation of the ion flow modulation electrode according to the present invention. 1... Signal processing circuit, 2, 21, 22, 23...
...Drive circuit, 3...Control circuit, 4...Ion flow modulation electrode, 4a...Common electrode, 4b...Control electrode,
4c... Ion passage hole, 5... Corona ion generator, 5a... Corona wire, 6... Rotating drum, 7... Development device, 8... Transfer electrode, 9... Separation claw, 10... Static elimination electrode , 11... Developer scraping plate, 12... Fixing device.

Claims (1)

[Claims] 1. Charged particle flow modulation comprising an insulating layer sandwiched between a common electrode and a control electrode for applying an image signal, and a plurality of charged particle flow passage holes penetrating the insulating layer and both electrodes arranged. dividing the common electrode and control electrode of the electrode into a plurality of groups in the arrangement direction of the charged particle flow passage holes;
Each of the common electrode groups divided in this way is arranged so as to be offset from each opposing control electrode group, and is opposed to the control electrode group whose passage through the charged particle flow is to be controlled in accordance with an image signal during recording. A potential is applied to two adjacent common electrode groups to allow the passage of the charged particle flow, and a potential to block the passage of charged particles is applied to the other common electrode group and another control electrode group. An electrostatic recording device characterized in that it is configured to form an electrostatic charge latent image on a charge carrier by performing the above operation every time switching is performed. 2. The electrostatic recording device according to claim 1, wherein the boundary between two adjacent common electrode groups is located at the center of each control electrode group.