JPS6082357A - Charged electrode structural body for inkjet recorder - Google Patents

Abstract

PURPOSE:To preclude short-circuiting between adjacent electrodes preventing ink fouling on an charged electrode due to scattering of ink at the starting or stopping of ink jetting with a simple construction by making the bore diameter of an ink absorbing member smaller than that of the charged electrode to absorb scattering ink by an ink absorbing member. CONSTITUTION:In the making of a charged electrode 1, a plateshaped body 2 made of an insulating material is bored and a metal electrode section 3 is formed by plating or other means to be connected to an electric circuit with a lead section 4. On both sides of the charged electrode 1 thus made, spacers 5 and 5 are arranged which are made of an insulating material such as resin and bored concentric with the holes of the charged electrode. It is desired that the diameter of the holes 6 of the spacer 5 should be larger than the bore diameter of the charged electrode 1. The diameter of holes 5 of an ink absorbing member is desirably smaller than the bore diameter of the charged electrode 1. To secure the sufficient bore and pitch accuracy, a stainless sintered metal is desired to be etched. Keep plates 9 and 9 made of an insulating material are arranged with a notch enough to be free from ink fouing due to scattering of ink. These members are assembled integral so as to make the holes on these members concentric with each other utilizing a pin hole 10 for positioning or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a charging electrode structure for preventing staining of charging electrodes in a multi-nozzle inkjet recording apparatus.

In Juren's multi-nozzle inkjet recording device, as the nozzles are mounted at a high density, the nozzle pinch interval has become extremely narrow, and the charged electrode interval has become narrow as well. Due to the ink scattering, the charging electrode becomes dirty, causing corrosion of the electrode, damage due to discharge breakdown, and electrical short circuit between adjacent electrodes.

Conventionally, in order to prevent damage to charging electrodes due to electrochemical causes, electrodes were made of corrosion-resistant noble metals (
(Japanese Unexamined Patent Publication No. 133434/1983).

A charging electrode made of stainless steel that is sufficiently resistant to damage caused by discharge breakdown has been proposed (Japanese Unexamined Patent Publication No. 55-3988), but in both cases, the charging electrode made of metal is exposed. Contamination occurs due to ink scattering when ink jetting starts and stops, resulting in electrical short circuit between adjacent electrodes.

In addition, a plurality of dielectric sheets each having an opening through which an inkjet flow passes and a charging electrode formed around it are laminated,
A dielectric sheet that does not have an electrode pattern on the outermost layer and has an opening concentric with the opening so as not to expose the charging electrode part (Japanese Patent Application Laid-Open No. 13731/1989), made of a photosensitive material. A plurality of layers is exposed through a mask to 1 (q source) and the exposed areas of the photosensitive material layer are etched to form a pattern of apertures and conductor tracks such that each aperture is concentric. Similar layered bodies with an opening in the outermost layer but without a conductor pattern are stacked and bonded by heating to prevent exposing the charged electrode part (Japanese Patent Application Laid-Open No. 53-8241!5).
has been proposed, but such electrodes are very expensive and, if the ejection direction changes due to partial clogging, the ink directly collides with the charging electrode, causing damage to the adjacent charging electrode. There are disadvantages such as ink flowing into the ink, blocking the ink flying path, and further worsening ink flying.

Furthermore, when starting and stopping ink jetting, the time required for the transient state of the ink flow to subside and to reach a stable state, the lower deflection plate and charging electrode are evacuated from the vicinity of the ink droplets, and the movable gutter is positioned on the nozzle plate. This device prevents ink from adhering to electrodes by trapping ink during periods of non-operation, thereby preventing the occurrence of electrical short circuits (Japanese Patent Laid-Open No. 56-467).
No. 68) has been proposed, but the mechanism becomes extremely complicated.

Kaida: The present invention was developed in view of the above circumstances, and has a simple configuration that prevents ink stains on charging electrodes due to ink scattering when starting or stopping ink jetting, and prevents the occurrence of electrical short circuits between adjacent electrodes. This is what we are trying to prevent.

(2) The structure of the present invention will be described below based on Examples.

The figure shows an embodiment of the charging electrode structure according to the present invention, in which the charging electrode 1 is formed by drilling holes in a plate-like body 2 made of an insulating material, forming a metal electrode part 3 by plating or other means,
The lead portion 4 connects to an electric circuit. Spacers 5.5 made of an insulating material such as resin and having a hole concentric with the hole in the charging electrode are arranged on both sides of the charging electrode l. The diameter of the hole 6 of the spacer 5 is desirably larger than the hole diameter of the charging electrode 1, and may have a structure with a notch like a holding plate. After the spacers 5, 5, an ink absorbing member 8.8 having a hole 7 concentric with the hole in the charging electrode 1 is arranged. It is desirable that the diameter of the hole in the ink absorbing member is smaller than the diameter of the hole in the charging electrode 1. This ink absorbing member may be made of porous plastic, but in order to ensure sufficient hole diameter and pitch accuracy, it is preferably etched stainless steel sintered metal.

A holding plate 9.9 made of an insulating material is disposed after the ink absorbing member 8.8 and has sufficient notches to prevent ink from being contaminated by ink scattering when ink jetting is started or stopped. Note that these members are connected to the positioning pin hole 10.
etc., it is assembled integrally so that the holes of each member are concentric.

In such a configuration, even when the ink flow is unstable at the time of starting or stopping ink jetting, the diameter of the hole in the ink absorbing member is smaller than the hole diameter of the charging electrode 1, so that the scattered ink is absorbed into the ink absorbing member 8. Even if the ejection direction changes due to partial clogging, the ink is absorbed by the ink absorbing member and does not stain the adjacent charged parts with ink.

Background of the Invention As described above, according to the present invention, the ink scattering flow at the time of starting or stopping ink jetting is absorbed by the ink absorbing member, and it is possible to prevent the occurrence of electrical short circuits due to ink stains on the charging section, and also to prevent partial Even when the ejection direction changes due to clogging, the ink absorption of the ink absorbing member prevents the adjacent charged parts from being contaminated with ink and secondary ink scattering. By contacting other ink absorbing members after assembly, it is possible to prevent the ink absorbing members from becoming saturated with ink.

[Brief explanation of the drawing]

The figure is a diagram showing one embodiment of a charging electrode structure according to the present invention. DESCRIPTION OF SYMBOLS 1... Charging electrode, 3... Metal electrode part, 4... Lead part, 5... Spacer, 8... Ink absorption member. 9... Pressing plate.

Claims (1)

[Claims] An inkjet recording device comprising: a charging electrode that charges ink droplets through an opening through which an inkjet flow passes; and an ink absorbing member having an opening whose central axis is aligned with the central axis of the charging electrode opening and which is smaller than the charging electrode opening. Charged electrode structure.