JPS62227755A - Ink nozzle for static acceleration-type ink jet recording - Google Patents

Abstract

PURPOSE:To miniaturize and reduce the cost of an ink nozzle by constituting one end of a flat multicore cable for an ink nozzle in a sandwich form using a support plate and an ink guide. CONSTITUTION:A flat multicore cable 1 consists of a electroconductive fine wire 5 arranged on the upper surface of a support plate 2 which is stuck to the former in an integral assembly with one end of the cable formed on a straight line. Further the end of each electroconductive fine wire 4 is exposed on the one end and this end is allowed to operate as an electric charge injection electrode. The support plate 2 and an ink guide 3 are formed with an electric insulation material such as glass or ceramic. The ink guide 3 consists of the tip of a plate-shaped member with almost the same width as the flat multicore cable 1, the tip tapering into a wedge form. In addition, a groove 7 extending at right angle with the axial line of the electroconductive fine wire 4 on a surface opposed to the flat multicore cable 1, while a long hole 8 is formed in such a way that it may be connected to the groove 7 from the opposite surface. Consequently the one end of the flat multicore cable is used as an electric charge injection electrode, and the other is connected to a high potential pulse generation means directly. For these reasons, the cost involved can be reduced and the device be miniaturized.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an ink nozzle for electrostatic acceleration type inkjet equipped with a slit-shaped ink ejection port used in printer devices, copying devices, etc. .

(Prior Art) Electrostatic acceleration type inkjet recording devices in which ink ejection ports are formed in the shape of slits have been known. Since this recording device is less likely to cause ink clogging and is capable of high-speed recording, it is desired to be put to practical use in copying machines.

As a conventional technology of an electrostatic acceleration type inkjet recording device having a slit-shaped ink jetting port, for example, Japanese Patent Laid-Open No. 56-4
There is one disclosed in No. 467. This device consists of a slit-shaped ink jetting port with a large number of electrodes arranged on the inner surface of the slit, a back electrode provided opposite to the slit-shaped ink jetting port, and a large number of electrodes arranged inside the slit-shaped ink jetting port. means for applying a voltage pulse corresponding to a recording signal to the electrode of the recording signal. The ink near the electrode selected from a large number of electrodes in the ink ejection port and to which a voltage pulse is applied is attracted and accelerated toward the back electrode by the electrostatic field formed between the selected electrode and the back electrode, and is placed between the electrodes. Ink dots are formed on the printed recording paper.

This type of electrostatic acceleration type inkjet recording device has a slit-shaped inkjet nozzle, so it has the advantage of being easier to maintain compared to other types of inkjet recording devices. Since it is possible to arrange a large number of electrodes at high density, there is an advantage that ink ejection control can be performed at high density.

By the way, conventionally, a large number of electrodes disposed within a slit-shaped ink jetting port have been removed by etching only a predetermined portion forming the slit-shaped ink jetting port, as disclosed in Japanese Patent Laid-Open No. 56-42664, for example. They were created using a method of forming a conductive material or a method of applying a conductive material only to a predetermined portion of a plate-like member. Therefore, the connection between the many electrodes arranged inside the slit-shaped ink jetting port and the voltage pulse generation source for applying voltage pulses to each of these electrodes is done by soldering lead wires or by using commercially available connectors. I was doing a lot of things.

However, the arrangement density of electrodes in the vicinity of the slit-shaped ink ejection ports is generally about 4 electrodes/rrm to 10 electrodes/rrm, and the number of man-hours required to connect lead wires to each of these electrodes is large. There was a drawback that manufacturing costs could not be reduced.

In addition, in the conventional technology in which a connector is used to connect the electrode disposed inside the slit-shaped ink ejection port and the voltage pulse generation source, in order to facilitate connection with the connector, the electrode arrangement density at the connection part is set to at least one electrode/electrode. It is necessary to make it ytra. Therefore, if the electrode pattern shape is devised so that the electrode array density at the connection part of the connector is sparser than the electrode array density at the ink jet nozzle, the length of the electrode array at the connection part with the connector will be reduced to slit-like ink jet nozzle. slit length of 4
There was a problem in that the recording device became larger by 10 times or more.

(Problems to be Solved by the Invention) As described above, in the conventional electrostatic acceleration type inkjet recording ink nozzle, a plurality of electrodes arranged inside the slit of the slit-shaped ink ejection port and a voltage pulse generation source are used. There was a problem in that the connections were weak, which made it impossible to reduce costs and downsize.

In view of these circumstances, it is an object of the present invention to provide an ink nozzle for electrostatic acceleration type inkjet recording that can be miniaturized and reduced in cost.

[Structure of the Invention] (Means for Solving Problems) The ink nozzle according to the present invention is constructed by sandwiching one end of a flat multicore cable between a support plate and an ink guide. The flat multicore cable has one end of conductive IIII covered with an electrically insulating material lined up and fixed on a plane, and the end face of the conductive thin wire is exposed at one end, and these end faces are arranged in a straight line. It has become a thing.

(Function) In the present invention, each conductive thin wire constituting the flat multicore cable functions as a charge injection electrode. Each of the conductive thin wires is electrically insulated from each other by a coating of electrically insulating material, and has sufficiently high mechanical strength compared to metal foil or the like, so that one end side can be arranged with high density. On the other hand, since each thin conductive wire at the other end is flexible, it can be directly connected to high voltage pulse generating means.

The oil-based ink supplied from the ink guide can smoothly reach one end of the cable through the grooves between the conductive thin wires of the flat multicore cable.

Since the end face of each thin wire is exposed at one end of the cable, charges are injected when the ink comes into contact with this end face.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an external view of an ink nozzle for electrostatic acceleration type inkjet recording according to this embodiment, and FIG. 2 is an enlarged view with a portion of the main part cut away.

This ink nozzle consists of a flat multicore cable 1 and a support plate 2 provided to sandwich one end of the flat multicore cable 1.
and an ink guide 3.

The flat multicore cable 1 is made by covering a plurality of thin conductive wires 4 with an electrically insulating material 5, arranging them so that one end is lined up in a straight line, and bonding the electrically insulating materials 5 together. configured. When forming this flat multicore cable 1,
It is desirable that the conductive thin wires 5 are arranged on the upper surface of the support plate 2 and fixedly integrated with the support plate 2. Then, after fixing and integrating,
One end of the flat multicore cable 1 is formed into a straight line by polishing one end, etc., and each conductive I [BFii
The end face of No. 4 is exposed to the above one end face. This end face functions as a charge injection electrode. Note that when forming the flat multicore cable 1, the adhesive may be solidified while the conductive thin wire 4 is being tightened between the support plate 2 and the ink guide 3. However, in this case, it is necessary to prevent the adhesive from protruding into the ink guiding portion between the ink guide 3 and the flat multicore cable 1. Furthermore, spacers 6 may be placed on both sides of the flat multicore cable 1 in order to ensure a predetermined gap in the portion that guides the ink.

The conductive thin wire 4 is not particularly limited as long as it is a material that is electrically conductive, has high tensile strength, and is not easily broken even when bent, and is used, for example, as a material for forming a multineedle electrode for electrostatic recording. A thin nickel metal wire is preferred because it can be directly soldered to the output terminal of the voltage pulse generation source and is resistant to rust. Further, its length is set to be sufficient for connection to the output terminal of the voltage pulse generation source.

The support plate 2 and the ink guide 3 are made of an electrically insulating material such as glass, ceramic, or a glass fiber reinforced synthetic resin plate. The ink guide 3 is a flat multicore cable 1
The distal end of the plate-like body having approximately the same width as 1 is formed into a wedge shape whose thickness gradually decreases, and a conductive thin wire [14's axial center line A groove 7 is formed extending perpendicularly to the groove 7, and an elongated hole 8 is formed so as to communicate with the groove 7 from the opposite surface. By filling ink through the elongated hole 8, the groove 7 functions as an oil pot. Note that the ink guide 3 may have a wedge-shaped distal end slightly retracted from one end of the flat multicore cable 1 as shown in the figure. This limits the amount of ink that adheres to the tip, making it possible to form sharp dots.

In the ink nozzle configured as described above, when the grooves 7 of the ink guide 3 are filled with ink, the ink is transmitted through the plurality of grooves formed between the flat multicore cable 1 and the ink guide 3 by capillary action. The ink oozes out to the end surface of the flat multicore cable 1, which serves as an ink spout. Since the ink covers the end face of each conductive thin wire 4, when a high voltage pulse is selectively applied to the conductive thin wire 4 by a voltage pulse generation source, the in-phase 1! ! Charge is injected into the ink that contacts the end surface of 4,
Further, the charged ink is attracted and accelerated toward the back electrode by an electrostatic field between the ink nozzle and the back electrode (not shown) generated by the high voltage pulse.

As a result, ink dots are formed on the recording paper disposed between the ink nozzle and the back electrode.

Next, the results of two practical examples actually conducted by the inventors will be shown.

<Example 1> A nickel metal thin wire with a diameter of 80 mm was used as the conductive thin wire, and a polyurethane resin was used as the insulating material covering the thin wire. A flat multicore cable having a width of 50 m at one end was formed by disposing 402 of these conductive thin wires at a spacing of 8 wires per shoe. This flat multicore cable was adhesively fixed to the upper surface of a support plate made of a glass plate having a length of 50 m, a width of 80 m, and a thickness of 21 m using an epoxy resin adhesive.

Next, epoxy 5Ill series adhesive was applied to both sides of the flat multicore cable 1, which was adhesively fixed on the glass plate.
A 0 m polyester film was placed thereon, and an ink guide was further pressed against it to integrate it. As an ink guide, a groove for an ink reservoir with a width of 50M, a length of 10M%, and a depth of 1 inch was provided on a glass plate with a width of 80 #l1l11, a length of 22NR, and a thickness of 2mm, and the tip side of the groove was formed into a wedge shape. I used something.

Note that the gap between the flat multicore cable and the support plate, which is formed on the opposite side of the slit-shaped ink jetting port, was filled with an adhesive to prevent ink from leaking.

The tip of the thus obtained bonded body was polished with sandpaper so that the end surfaces of the conductive thin wires were exposed on the same plane. The sandpaper used was one on which alumina powder with a particle size of 1 or less was coated and fixed. The distance from the tip of the ink guide to the tip of the flat multicore cable is approximately 3
0AI! It was set to n.

The conductive thin wire of the ink nozzle obtained in this way is
An inkjet recording experiment was conducted by soldering each output terminal of a high voltage pulse generation source.

In this inkjet recording experiment, the conductivity was 0.005μ
3/r:m 1 Ink with a surface tension of 32 dyn/c JR1 viscosity 12 cst was used, the distance between the slit-shaped ink jet port and the back electrode was 0.4 m, and the peak value of the voltage pulse applied to the nickel metal thin wire was -300 ■. Pulse width is 2
A voltage pulse with a peak value of +2100 V, a pulse width Q, 5 m5 ec, and a repetition frequency of 1 kpps was applied to the back electrode at 5 m5 ec. As a result, on the recording paper,
Ink dots corresponding to the voltage pulses applied to the thin nickel metal wire were formed.

<Example 2> No member is inserted between the support plate forming the slit-shaped ink jetting port and the ink guide to maintain a constant distance between the two plates, and the tip of the ink guide is set 0.3 InI from the tip of the support plate.
An ink nozzle similar to that of Example 1 above was prepared except that it was moved back by about n.

When an inkjet recording experiment similar to that described above was conducted using this ink nozzle, good recording dots were obtained in this case as well.

[Effects of the Invention] As described above, according to the present invention, one end of the flat multicore cable can be used as a charge injection electrode, and the other end can be directly connected to the high voltage pulse generation means. This eliminates the step of connecting lead wires to each lead wire one by one, reducing costs, and does not increase the size of the connecting portion, contributing to miniaturization of the entire device.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of an ink nozzle for electrostatic acceleration type inkjet recording according to an embodiment of the present invention, and FIG. 2 is an enlarged perspective view with a portion of the ink nozzle cut away. 1... Flat multicore cable, 2... Support plate, 3...
Ink guide, 4... Conductive thin wire, 5... Electrically insulating material, 6... Spacer, 7... Groove, 8... Long hole.

Claims (2)

[Claims] (1) A flat multicore cable in which one end of a conductive thin wire coated with an electrically insulating material is lined up and fixed on a plane, the end surface of the conductive thin wire is exposed at one end, and these end surfaces are arranged in a straight line. and a support plate for supporting the flat multicore cable, and an ink guide that is provided so as to sandwich one end of the flat multicore cable between the support plate and stores ink therein. An electrostatic acceleration type inkjet recording ink nozzle featuring: (2) The ink guide is characterized in that a groove extending in a direction perpendicular to the axis of the thin conductive wire is provided as an ink reservoir on the surface facing the flat multicore cable. The ink nozzle for electrostatic acceleration type inkjet recording according to item 1.