JPH0825685A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To obtain an image forming apparatus capable of being efficiently produced with high accuracy by forming an aperture electrode element by mutually connecting a plurality of divided aperture electrode elements. CONSTITUTION:The passage of charged toner through apertures is controlled by an aperture electrode element 1 equipped with a plurality of apertures and an image is formed on the support positioned on the side opposite to a toner supply source through the aperture electrode element 1. In this image forming apparatus, the aperture electrode element 1 is formed by mutually connecting a plurality of divided aperture electrode elements 1a. The devided aperture electrode elements 1a have such a structure that the aperture electrode element 1 is divided in the direction crossing the arrangement direction of a plurality of apertures. Further, a dividing position is set between adjacent aperture electrodes. As a result, a highly accurate image forming apparatus suppressed in the generation of deficiency can be efficiently produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a copying machine, a printer,
The present invention relates to an image forming apparatus that can be used for plotters, facsimiles, and the like.

[0002]

2. Description of the Related Art Conventionally, as an image forming apparatus of this type, an electrode having a plurality of openings (hereinafter referred to as an aperture) is used, and a voltage is applied to the electrode based on image data. U.S. Pat. No. 3,689,935 discloses controlling toner particles so that they can pass through the aperture and forming an image on the support by the toner particles that have passed.

In this image forming apparatus, a flat plate made of an insulator, a continuous reference electrode provided on one surface of the flat plate, and a plurality of control electrodes insulated from each other formed on the other surface. An electric potential is selectively applied between the reference electrode and the control electrode and an aperture electrode body that is formed by stacking three electrodes and has at least one row of apertures that penetrates the three electrodes for each control electrode. Means for supplying, means for supplying charged toner particles such that the flow of the toner particles passing through the aperture is modulated by the applied potential, and the support and the aperture electrode body can move relative to each other, And a means for positioning the support in the toner particle flow path.

US Pat. Nos. 4,743,926 and 4,755.
837, 4780733, and 4814796.
Each specification discloses an image forming apparatus configured such that the control electrode of the aperture electrode body is oriented toward the support side and the reference electrode of the aperture electrode body is oriented toward the toner supply side. .

In contrast, US Pat. No. 4,912,489
In the specification, by arranging the reference electrode of the aperture electrode body toward the support side and the control electrode of the aperture electrode body toward the toner supply side, the voltage applied to the control electrode at the time of off There is described a technique capable of suppressing the above-mentioned to about 1/4 as compared with the image forming apparatus disclosed in the above-mentioned US patent.

The off state means that the toner particles are not adhered to the support, that is, the blank portion of the image is formed. On the other hand, the on state means that the support is on the support. This means the case where a toner image is formed on.

[0007]

However, the aperture electrode body used in the image forming apparatus as described above is
After forming a wiring to be a control electrode on an insulating sheet of about 25 μm, a hole is formed to form an aperture, and further, an IC is mounted. It is very difficult to form extremely fine wiring and to mount a large number of ICs, and in particular, a large number of wirings and openings corresponding to the number of pixels are formed in the longitudinal direction, and each IC is formed. Since it is necessary to form a connection point for connecting the wiring, there is a problem that it is very difficult to manufacture these with a high yield.

Therefore, a defect such as a connection defect is likely to occur, and if even one of the connection points with a large number of wirings or ICs is defective, the aperture electrode body cannot be used. There is a problem in that it must be carried out or discarded as a defect, which is very wasteful in the production process.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an image forming apparatus capable of producing with high accuracy and efficiency.

[0010]

In order to achieve this object, the image forming apparatus of the present invention controls an aperture electrode body having a plurality of apertures to control the passage of the charged toner through the aperture electrode body. In an image forming apparatus that forms an image on a support located on the side opposite to the toner supply source, the aperture electrode body is formed by connecting a plurality of divided aperture electrode bodies to each other.

Further, it is preferable that the divided aperture electrode body has a structure in which the aperture electrode body is divided in a direction intersecting with an arrangement direction of the plurality of apertures.

Further, it is desirable that the division position is set between the adjacent aperture electrodes.

[0013]

The image forming apparatus of the present invention having the above structure is
Since the aperture electrode body is formed by connecting the plurality of divided aperture electrode bodies to each other, it is possible to suppress the occurrence of defects and efficiently produce the electrodes.

Further, since the divided aperture electrode body has a structure in which the aperture electrode body is divided in a direction intersecting with the arrangement direction of the plurality of apertures, it is easy to form the divided aperture electrode body itself and the connecting process is also easy. Is.

Further, by setting the division position between the adjacent aperture electrodes, it is easy to carry out the connecting process, and an aperture electrode of high quality can be produced.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the image forming apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the outline of the image forming apparatus of this embodiment. As shown in FIG. 1, a cylindrical back electrode roller 22 is rotatably disposed on a chassis (not shown) above the aperture electrode body 1 with a gap of 1 mm. Support 20 inserted in the gap
Are configured to be transported. A toner supply device 10 is arranged below the aperture electrode body 1 along the longitudinal direction of the aperture electrode body 1, and the support body 20 conveyed by the back electrode roller 22 advances. The fixing device 26 is arranged at the front.

Next, the details of each of the above components will be described.

The toner supply device 10 comprises a toner case 11 which also serves as a housing of the entire device, a toner 16 accommodated in the toner case 11, a supply roller 12, a toner carrying roller 14 and a toner layer regulating blade 18. ing. Here, the toner carrying roller 14 carries the toner 16 and conveys it toward the aperture electrode body 1, and the supply roller 12 supplies the toner 16 to the toner carrying roller 14. The toner supply device 10 including the toner carrying roller 14
It constitutes the toner supply source of the present invention.

The supply roller 12 and the toner carrying roller 14 are rotatably supported by the toner case 11 in the directions of arrows a and b in FIG. Also,
Both are arranged in contact with each other.

Further, the toner layer regulating blade 18 is
The toner 16 is pressed against the toner carrying roller 14 so that the amount of the toner 16 carried on the toner carrying roller 14 is adjusted to be uniform on the surface, and the carried toner 16 is uniformly charged. It is configured.

Next, the structure of the aperture electrode body 1 of this embodiment will be described with reference to FIGS.

An overall perspective view of the aperture electrode body 1 is shown in FIG.
A detailed perspective view of the aperture portion is shown in FIG. 3, respectively.

As shown in FIG. 2, the aperture electrode body 1 is
On the holding member 5 on the plate, a plurality of divided aperture electrode bodies 1
It is held and fixed in the state where a is connected. In the case of the present embodiment, the recording head having an A4 size paper width is configured by connecting five divided aperture electrode bodies 1a.

In each divided aperture electrode body 1a, as shown in FIG. 3, a plurality of apertures 6 having a diameter of about 60 μm are formed in one row in the longitudinal direction of an insulating base material 2 made of polyimide having a thickness of 25 μm. A control electrode 4 having a thickness of 8 μm is formed for each aperture 6 on the upper surface of the base material 2. This aperture 6
The pitch is 125 μm in the case of 200 dpi, for example. Further, the control electrode 4 is connected to one end of the conductive wire portion 3, and the other end of the conductive wire portion 3 is connected to a drive IC 7 arranged on the base material 2.

Then, the aperture electrode body 1 of this embodiment is formed by connecting a plurality (five in this embodiment) of the divided aperture electrode bodies 1a configured as described above.

Next, the connecting portion of the divided aperture electrode body 1 will be described.

FIG. 4 shows a plan view of the aperture electrode near the connecting portion. A plurality of aperture electrodes 3a composed of the aperture 6, the control electrode 4 and the conducting wire portion 3 are set so that the connecting portion 9 is located between the adjacent aperture electrodes 3a in the aperture electrode body 1 arranged at a predetermined pitch. ing.
The connecting portions 9 are connected by means for integrating adjacent polyimide films. There are various methods such as an adhesive method, an adhesive tape method, and a diffusion bonding method. By either method, adjacent aperture electrodes can be integrated and formed so that continuous recording is possible.

Further, as shown in FIG. 4, since the connecting portion 9 is set between the adjacent aperture electrodes 3a and is set in the direction orthogonal to the arrangement direction of the apertures 6, the connecting process is performed. It is easy to apply and the finish of the aperture electrode body 1 becomes beautiful.

As shown in FIG. 1, the aperture electrode body 1 has the toner carrying roller 1 at the aperture position of the insulating member 2 with the control electrode 4 facing the support 20 side.
It is pressed against 4.

The positional relationship between the aperture 6 of the aperture electrode body 1 and the toner carrying roller 14 will be described in detail.

As shown in FIG. 6, each aperture 6 is arranged so that its center line 30 passes through the uppermost portion of the peripheral surface of the toner carrying roller 14 and the central shaft 32 of the toner carrying roller 14. There is. According to this, each aperture 6
Based on the uppermost part of the peripheral surface of the toner carrying roller 14,
By being evenly arranged on the left and right, the distribution of the toner 16 passing through each aperture 6 can be made uniform in the entire area within the aperture. Also, the wall surface of the aperture 6 and the toner 1
6 is parallel to the flight direction, so that the toner 16 can be stably
Can be made to fly to the support 20 side.

Further, the aperture electrode body 1 itself is shown in FIG.
As shown in FIG. 3, the toner holding roller 14 is pressed against the toner carrying roller 14 so as to bend at the same angle to the left and right about the aperture 6, so that the contact area between the aperture electrode body 1 and the toner carrying roller 14 can be increased. At the same time, the periphery of the lower portion of the aperture 6 can be pressed uniformly to the left and right, so that unevenness in the density of the toner 16 can be suppressed as much as possible.

A control voltage applying circuit 8 is connected between the control electrode 4 and the toner carrying roller 14.
The control voltage application circuit 8 is configured to apply a voltage of 0 V or +50 V to the control electrode 4 based on the image signal. Further, the back electrode roller 22
A DC power supply 24 is connected between the toner carrying roller 14 and the toner carrying roller 14, and this DC power supply can apply a voltage of +1 kV to the back electrode roller 22.

Next, the operation of the image forming apparatus configured as described above will be described.

First, the toner carrying roller 14 and the supply roller 12 rotate in the directions of arrows a and b in FIG.
Are rubbed against the toner carrying roller 14 and carried on the toner carrying roller 14 in a state of being negatively charged. The carried toner 16 is thinned by the toner layer regulating blade 18 and is negatively charged, and then is conveyed toward the aperture electrode body 1 by the rotation of the toner carrying roller 14. Then, the toner 16 on the toner carrying roller 14 is supplied to the bottom of each aperture 6 while being rubbed by the base material 2 of the aperture electrode body 1.

Here, in accordance with the image signal, a voltage of +50 V is applied from the control voltage applying circuit 8 to the control electrode 4 corresponding to the portion forming the image. As a result, the control electrode 4 is formed near the aperture 6 corresponding to the image forming portion.
The electric potential difference between the toner carrying roller 14 and the toner carrying roller 14 forms an electric field from the control electrode 4 toward the toner carrying roller 14. Due to this electric field, the toner 16 charged negatively
Receives an electrostatic force in the direction of higher potential and is drawn from the toner carrying roller 14 through the aperture 6 to the control electrode 4 side. The extracted toner 16 further flies toward the support body 20 due to an electric field formed between the support body 20 and the aperture electrode body 1 by the voltage applied to the back electrode roller 22, and the support body 20 is supported. Deposit on top to form pixels.

Further, a voltage of 0V is applied from the control voltage applying circuit 8 to the control electrode 4 corresponding to the part where the image is not formed. As a result, since no electric field is formed between the toner carrying roller 14 and the control electrode 4, the toner 16 on the toner carrying roller 14 does not receive an electrostatic force and does not pass through the aperture 6.

Then, the support 20 is fed by one pixel in the direction perpendicular to the aperture row while the toner 16 forms one row of pixels on the surface thereof.

By repeating the above process, a toner image is formed on the entire surface of the support 20, and then the formed toner image is fixed on the support 20 by the fixing device 26.

As is clear from the above description, the support 2
The aperture electrode body 1 plays an extremely important role in the process of forming an image on the image display device 0, and the voltage data is reliably controlled from the drive IC 7 to the control electrode 4 by the transmitted image data. The aperture 6 needs to be accurately formed. Even if it is installed in a normal fax machine with 200 dpi and 1728 holes, 1728
All the apertures 6 and the control electrodes 4 must be accurately formed, and the wiring of the conductive portion 3 must be surely connected to each IC. Therefore,
In manufacturing the aperture electrode body 1, it is very difficult to create such a large number of mechanisms without defects. However, as shown in this embodiment, a plurality of divided aperture electrode bodies 1a are connected to form the aperture electrode body 1 of a desired size, and the aperture electrode body 1 is configured as one recording head, so that its manufacture is extremely easy. become. That is, since the divided divided aperture electrode body 1a is downsized,
Since a manufacturing apparatus having a small moving stroke can be used in flowing the manufacturing line, accuracy can be improved and yield can be improved.

Further, inspection is performed for each divided aperture electrode body 1a, and even if a defect occurs and repair is not possible, it is sufficient to discard the divided aperture electrode body 1a in small units, and the amount of waste can be suppressed as compared with the conventional one. You can When assembled to the holding member 5, only the non-defective products that have passed the inspection for each divided aperture electrode body 1 can be assembled to form the aperture electrode body 1. Therefore, even with a long head, high accuracy and high efficiency are achieved. It can be formed well.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention.

For example, although the control voltage of the aperture corresponding to the non-image portion is set to 0V in the above embodiment, it may be a negative voltage. In this case, an image with less fogging can be obtained.

Further, in this embodiment, as shown in FIG. 4, the connecting portion 9 is set so as to be located between the adjacent aperture electrodes. However, as shown in FIG. 5, the connecting portion 9 is formed on the aperture electrode. You may set so that it may be located. Furthermore, the connecting portion may be set diagonally over the plurality of aperture electrodes. In this case, since the connecting portion is dispersed over the plurality of aperture electrodes, the connecting portion can be made relatively inconspicuous.

[0046]

As is apparent from the above description, the image forming apparatus of the present invention forms an aperture electrode body by connecting a plurality of divided aperture electrode bodies to each other, so that a defect occurs. It is possible to efficiently produce an image forming apparatus with high accuracy.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an image forming apparatus of this embodiment.

FIG. 2 is a perspective view showing a configuration of an aperture electrode body of this embodiment.

FIG. 3 is an enlarged perspective view of the vicinity of the aperture of the aperture electrode body.

FIG. 4 is a plan view showing a connecting portion of an aperture electrode body.

FIG. 5 is a plan view showing a connecting portion of an aperture electrode body.

FIG. 6 is a diagram schematically showing a configuration of an aperture electrode body and a toner carrying roller used in the image forming apparatus of this embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aperture electrode body 6 Aperture 9 Connection part 10 Toner supply device 14 Toner carrying roller 22 Rear electrode roller

Claims (3)

[Claims] 1. An aperture electrode body having a plurality of apertures is used to control the passage of charged toner through the aperture plate, and an image is formed on a support located on the opposite side of the aperture electrode body from the toner supply source. The image forming apparatus, wherein the aperture electrode body is formed by connecting a plurality of divided aperture electrode bodies to each other. 2. The image forming apparatus according to claim 1, wherein the divided aperture electrode body has a structure in which the aperture electrode body is divided in a direction intersecting with an arrangement direction of the plurality of apertures. . 3. The image forming apparatus according to claim 1, wherein the division position is set between adjacent aperture electrodes.