JPS6384944A - Static recording head - Google Patents

Abstract

PURPOSE:To improve ion derivation efficiency by providing a head in which an ion flow course is formed between opposed insulation members, an ion generation part in which a high frequency high voltage is applied between both discharging electrodes and an ion flow control which controls the passage and interruption of generated ions. CONSTITUTION:A static recording head is composed of a head 10 in which an ion flow course 13 is formed between flat insulation members 11, 14, an ion generation part 20 provided at an outlet of the ion flow course 13 and an ion flow control 30. If a high frequency high voltage 23 is applied to each discharging electrode 21, 22 of the ion generation part 20, a differently oriented electric field is alternately formed in the range of an overlapping part. At that time, air breaks down dielectrically near the edge 22a of an upper discharging electrode 22, and positive and negative ions generate alternately from the edge 22a. Then generated ion groups 40 are gradually trapped and proliferated following the high-speed change of polarity of an applied voltage. Immediately these ions reach the ion flow control 30 provided at almost the same position as the ion generation part 20. Thus it is possible to eliminate an ion loss on the way to the ion flow control.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electrostatic recording head, and particularly to an electrostatic recording head in which a pair of discharge electrodes are arranged in a polymerized manner with an insulating layer interposed therebetween as an ion generating section. This invention relates to improvements in electrostatic recording heads.

[Prior Art] As a conventional electrostatic recording head, for example, Japanese Patent Application Laid-Open No. 59-1
There are those published in the publications No. 64154 and No. 59-190854. As shown in Fig. 4, an ion generator is constructed of a discharge wire 1 and a shield 2 surrounding the discharge wire 1, and an ion discharge path 3 is provided in the shield 2, and an ion discharge path 3 is provided for introducing compressed air. An air introduction path 4 is opened, and an appropriate number of control electrodes 5 are arranged in the ion exhaust path 3 in accordance with the pixel density.

In this type, a DC high voltage 7 is applied to the discharge wire 1.
When this is applied, a discharge occurs between the discharge wire 1 and the shield 2, and a large amount of ions are generated around the discharge wire 1 and guided to the ion exhaust path 3 side together with the introduced compressed air. At this time, when an appropriate image control signal 8 is applied to the control electrode 5, the ion flow passes or is blocked depending on the presence or absence of an electric field at each control electrode 5 portion. ! Static W1 according to pressure
A latent image is formed.

[Problems to be Solved by the Invention] However, in such a conventional electrostatic recording head, ions generated around the discharge wire 1 are directed radially toward the shield 2, and Since only a portion is taken out to the ion exhaust path 3 side together with the compressed air, there is a problem that a sufficient absolute amount of ions cannot be secured, making it unsuitable for high-speed recording.

As a means to solve this problem, for example, the one shown in FIG. 5 can be considered. This includes a head body 10 in which an ion flow path 13 is formed between a flat insulating member 11 and an insulating member 12 having a semi-cylindrical recess, and a flat insulating member 11 facing the ion flow path 13. The ion generating section 20 includes a pair of radiation RM poles 21 and 22 which are provided in a part and to which a high frequency high voltage 24 is applied and which are arranged in a superimposed manner with an insulating layer 23 interposed therebetween, and an ion generating section 20 in the vicinity of the exit of the ion flow path 13. A control electrode 31 corresponding to the pixel density and a counter control electrode 3 opposite thereto are located between the resupply edge members 11 and 12.
2, and an ion flow control section 30 which controls passage and interruption of the ion flow generated in the ion generation section 20 by appropriately applying an image control signal 33 between both control electrodes 31 and 32. Incidentally, reference numeral 35 is a DC bias power supply that applies a predetermined electric field between the exit portion of the head body 1G and the recording medium 6 to guide, for example, only positive ions toward the recording medium 6 side.

According to this type, releasell111! When the high frequency high voltage 24 is applied between the poles 21 and 22, the radiating RM pole 21 and 22
Electric fields with different directions are alternately formed between them. At this time,
As shown in FIG. 6, the ion flow path 1 is
The air near the edge portion 22a of the discharge electrode 22 facing 3 undergoes dielectric breakdown, and positive and negative ions are alternately generated from this edge portion 22a.
Since the polarity of the applied voltage changes rapidly, the ion group is gradually trapped and multiplied, and the ion group is immediately carried away to the recording medium 6 side together with the compressed air introduced into the ion flow path 13. Therefore, the absolute amount of ions reaching the recording medium 6 is set to be larger than that of the type shown in FIG.

However, in this type, after the ions are generated in the ion generator 20, the generated ions are transferred to the ion flow controller 3.
Since the configuration is such that the two are functionally separated from each other from the viewpoint of controlling at 0, the ion generation section 20 and the ion flow control section 30 are necessarily separated by a certain distance along the ion flow path 13! They will be spaced apart from each other. In this case, some of the ions generated in the ion generation section 20 collide with the wall surface etc. in the ion flow path 13 until reaching the ion flow control section 30 and are neutralized. The absolute amount of ions actually taken out decreases by the loss of ions until reaching 30, and by that amount,
This was an obstacle to achieving high-speed records.

[Problems to be Solved by the Invention] The present invention has been made by focusing on the above-mentioned problems. The present invention provides an electro-recording head.

That is, the present invention has a head main body in which an ion flow path is formed between opposing insulating members, a pair of discharge electrodes on one insulating member, which are arranged overlapping each other with an insulating layer interposed therebetween, and a discharge electrode between the two discharge MWi electrodes. An ion generating section to which a high frequency and high voltage is applied, and control electrodes are arranged on the other insulating member facing the ion generating section according to the pixel density, and each control electrode also serves as one of the discharge electrodes. and an ion flow control section to which an image control signal is applied between the counter electrode and the ion flow control section to control passage or interruption of the ion flow generated in the ion generation section.

In such technical means, the shape and size of the insulating member constituting the head body may be selected as appropriate, but the ion generation section and the ion flow control section may be provided at approximately the same location due to design. Therefore, it is not necessary to ensure a very long ion flow path. In addition, regarding the ion generation section, if it is of a type that applies high frequency and high voltage between discharge electrodes arranged with an insulating layer in between, the size of the discharge electrodes and the arrangement II will depend on the required generation ion company. However, in order to further improve the ion generation rate, it is necessary to change the design on the side facing the ion flow path.
! It is desirable to design the electrode so as to expand the area of the edge portion that essentially functions as an ion generation portion by providing a large number of notch recesses in the electrode. Furthermore, ion 1t4
T! As part 11, an image control signal is applied at least to the 11111 electrode side provided on the insulating member facing the ion generating part, and one of the discharge electrodes that is maintained at the ground potential is selected as the opposing control 1ffi pole. Just do it like this. Furthermore, as a method for transferring the generated ions to the recording medium side, compressed air is introduced into the ion flow path,
An electric field for guiding ions may be formed in advance between the head and the recording medium, or the like may be selected as appropriate.

[Operation] According to the technical means as described above, a pair of ion generators 1! When a high frequency and high voltage is applied between the electrodes, air dielectric breakdown occurs at the edge portion of the discharge electrode facing the ion flow path, and a large amount of ions are generated from this portion. Many of the generated ions immediately pass through and are blocked by the ion flow control unit installed at approximately the same location as the ion generation unit, and the passed ions move toward the recording medium to maintain a predetermined electrostatic potential. form an image.

[Embodiments] Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.

1 to 3, the basic structure of the electrostatic recording head is: a head body 10 in which an ion flow path 13 is formed between flat insulating members 11 and 14;
The ion generating section 20 is provided at the exit of the ion flow path 13, and the ion flow control section 30 is also provided at the exit of the ion flow path 13.

In this embodiment, the ion generating section 20 is provided with a lower discharge electrode 21 on one insulating member 11 facing the ion flow path 13, and an upper A discharge electrode 22 is provided, and a high frequency high voltage 24 is applied between both discharge electrodes 21 and 22. More specifically, the lower discharge electrode 21 is formed into a substantially rectangular shape, and is screen-printed with gold paste on the insulating member 11, and then shaped into a predetermined shape by a photolithography process. It is something that defines. Further, the insulating layer 23 is provided in a range that covers the lower discharge electrode 21, and is formed by screen printing and baking with glass paste, for example. Furthermore, the above upper number i! The electrode 22 is formed by screen-printing a gold paste onto the insulating layer 23 and then defining it into a predetermined shape through a photolithography process.

In this embodiment, the upper number '11? ! !
The poles 22 are arranged so as to overlap the entire area of the lower discharge electrode 21 except for one side edge, and the upper discharge electrode 22 is arranged so as to overlap the entire area except for one side edge of the lower discharge electrode 21. has been done.

The upper few WIW poles 22 have a large number of four notches 25 in the range where they are combined with the lower discharge electrode 21, and the group of the notches 25 is formed in a comb shape. Furthermore, each cut recess 25 is configured with a density of, for example, about 4 pieces/m, and each cut recess 25 and the cut recess 25
The width dimensions of the respective branch portions 26 formed therebetween are set to be approximately equal.

The ion flow control section 30 also controls the upper discharge electrode 2.
A pixel band r!
1 (for example, 12 lines/m)
It consists of a pole 31 and an opposing control m+ electrode 34 which also serves as the base portion 2γ of the upper discharge electrode 22 and is kept at ground potential, and each control 211'R pole 31 receives an image control signal 33 according to the image pattern. is applied. Incidentally, reference numeral 35 is a DC bias power supply similar to the conventional example.

Therefore, according to the electrostatic recording head according to this embodiment, the high frequency a is applied to each discharge electrode 21 and 22 of the ion generating section 20.
i! When the pressure 24 is applied, electric fields with different directions are created alternately in the overlapping area of each discharge electrode 21,22. At this time, the upper discharge electrode 22 facing the ion flow path 13
Dielectric breakdown occurs in the air near the edge portion 22a, and positive and negative ions 40 are alternately generated from this edge portion 22a, and as the polarity of the applied voltage changes rapidly, the generated ion 40 group is gradually trapped and multiplied. Ru. Particularly, in this embodiment, firstly, since the edge portion 22a is composed of the inner edge of the cut recess 25 and the protruding edge of the branch portion 26, the area of the edge portion 22a, in other words, the generation of ions 40. The area is sufficiently wide, and
The amount of ions 40 produced can be increased, and secondly,
Since the substantial overlapping area between the discharge electrodes 21 and 22 is reduced by the presence of the notch recess 25, the capacitance between the discharge electrodes 21 and 22 is set to be small. Accordingly, the current for charging and discharging the insulation 1[23] is suppressed to a relatively small value, and the discharge electrode 21.2
The power consumed between the two can be reduced.

The ions 40 generated by the ion generating section 20 are
immediately reaches the ion flow control section 30 provided at approximately the same location as the ion generation section 20. At this time, when an appropriate image control signal 33 is applied to the control electrode 31, an electric field is generated between the control electrode 31 to which the image control signal 33 is applied and the counter control electrode 34 in a direction perpendicular to the ion flow path 13. will be formed. Then, the corresponding ion 40 portion moves toward the control 611 electrode 31, 34 side by the electric field, and is neutralized and disappears at that portion, so that the ion flow is blocked in the electric field forming portion, while the ion flow is blocked in the electric field non-forming portion. The ions 40 pass toward the recording medium 6 together with the compressed air guided into the ion flow path 13, and an electrostatic latent image is formed on the recording medium 6 based on the ion flow. At this time, since the distance between the ion generation section 20 and the ion flow control section 30 is set to approximately zero, there is no possibility that the generated ions 40 are lost on the way to the ion flow control section 30. effectively avoided.

In addition, as the loss of ions 40 is suppressed, it is no longer necessary to set the ion flow rate unnecessarily high, and the compressed air flow can be reduced accordingly, making it possible to downsize the compressed air generator. You can also do it.

In the above embodiment, if the formation density of the notch recesses 25 of the upper discharge T1 electrode 22 is set to be thinner than the pixel density, even if the distribution of the amount of ions produced from the upper discharge electrode 22 varies to some extent, the Variations are effectively absorbed, and it becomes possible to make the ions m passing through each pixel corresponding portion of the ion flow control section 3G approximately equal. At this time, the potential of the electrostatic latent image dots can be kept approximately uniform, and density unevenness in the developed toner image can thereby be reliably avoided. Further, in the above embodiment, if the lower discharge electrode 21 is also formed with a notched recess similar to the upper discharge electrode 22, and the substantial overlapping area of both discharge electrodes 21 and 22 is reduced as much as possible, the discharge can be improved. By further reducing the capacitance between the electrodes 21 and 22, the power consumption between the discharge electrodes 21 and 22 can be further reduced.

[Effects of the Invention] As explained above, the electrostatic recording head according to the present invention has an ion generating section with high ion generation efficiency, and moreover, ions are generated at approximately the same location in the ion flow path. Since the ion flow control section is provided with a section and an ion flow control section, it is possible to eliminate the loss of ions on the way from the ion generation section to the ion flow control section. can be immediately guided to the ion flow control section and sent to the recording medium.Therefore, it is possible to ensure a sufficient absolute amount of ions, and accordingly higher speed recording can be realized.

Further, according to the present invention, one of the discharge electrodes, which is a component of the ion generation section, is also used as a component of the ion flow III control section, so that the head configuration can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of an electrostatic recording head according to the present invention, FIG. 2 is a cross-sectional view taken along line nm in FIG. 1, and FIG. 3 is a view taken from the n-direction in FIG. 4 is a cross-sectional explanatory diagram showing an example of a conventional electrostatic recording head, FIG. 5 is a cross-sectional explanatory diagram showing another example of a conventional electrostatic recording head, and FIG. It is an arrow view seen from the middle ■ direction. [Explanation of symbols] (10)...Head body (20)...Ion generating portion (21, 22)...Discharge electrode (23)...Insulating layer (25)...Notch recess (30) )...Ion flow control section (31)...Control electrode (34)...Opposed control tlllli electrode Patent applicant Fuji Xerox Co., Ltd. Agent
Patent Attorney Nakamura Konamizo (2 others) Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1) A head main body in which an ion flow path is formed between opposing insulating members, and a pair of discharge electrodes on one insulating member are arranged overlappingly with each other with an insulating layer interposed therebetween, and both discharge electrodes are provided. An ion generating section between which a high frequency and high voltage is applied, and control electrodes are arranged on the other insulating member facing the ion generating section according to the pixel density, and each control electrode also serves as one of the discharge electrodes. An electrostatic recording head comprising: an ion flow control section to which an image control signal is applied between a counter control electrode formed of a ion generator and an ion flow control section that controls passage or interruption of an ion flow generated in an ion generation section. 2) Claim 1, characterized in that the discharge electrode on the side facing the ion flow path has a large number of notch recesses.
The electrostatic recording head described in Section 1.