JPS6335353A - Printer head device - Google Patents

Abstract

PURPOSE:To prevent the missing of dot caused by shortage of ink in the tip end of a wire, by a method wherein a step portion on the wire is positioned within the area of an ink layer forming chamber when the wire is dormant and within a cylinder when the wire is operating. CONSTITUTION:An ink supply guide 7 is provided with an ink chamber 7B at the upper portion thereof; a wire guide hole 7A is divided into halves by an ink layer forming chamber 7C disposed on a wire support portion to form a guide hole 7b, which forms a cylinder portion 7d at the portion connecting with a guide small hole portion 7a. With the start of printing, an armature 3 is driven by a solenoid magnet 2, whereby a wire 6 moves from a dormant position to a printing position. At this time, a step portion 6C of the wire 6 pushes out an ink, contained in the cylinder portion 7d through the ink layer forming chamber 7C, toward a printing surface out of a space between a small diameter portion 6a of the wire 6 and the guide small hole portion 7a. With the wire6 returning to the dormant position, an ink 10A contained in the ink forming chamber 7C is sucked through an ink path 7F due to negative pressure and flows into the cylinder portion 7d. In this manner, a constant amount of ink is pushed out to the tip end portion of the wire 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer head device, and particularly to a printer head device suitable for a wire-driven dot printer.

[Conventional technology]

Many dot printers are configured to drive a plurality of wires to apply an impact force to paper via an ink ribbon, thereby performing predetermined printing. There are other dot printers that form dot characters and the like by wire drive without using an ink ribbon. In this method, ink is attached to the tip of a wire to perform printing.

[Problem that the invention seeks to solve]

Dot printers that use ink ribbons require an ink ribbon and an ink ribbon drive device in the printer head device, which has the disadvantage that the entire device tends to be complicated and large.

On the other hand, the method of printing by applying liquid ink directly to the wire has a disadvantage in that the method of applying the ink is difficult, and dots are likely to be missing. Many of these conventional printer head devices that use ink adhesion utilize only the capillary phenomenon that occurs between the wire and its guide hole when guiding the liquid ink to the tip of the wire. In this example, paper powder attached to the tip of the wire adhered to the inner wall of the guide hole, causing clogging, resulting in unstable ink supply.

[Purpose of the invention]

The present invention improves the disadvantages of the conventional example, and in particular, adopts a method of forcibly moving ink to the tip of the wire, thereby almost completely eliminating accidents of missing dots caused by insufficient ink at the tip of the wire. The purpose is to provide a printer head device that can perform the following steps.

Means for Solving Problem C] The present invention includes a plurality of wires, an electromagnetic magnet section that individually drives each wire via an armature, a wire guide that slidably supports each wire, and an ink supply. Comes with a guide.

The ink supply guide is arranged at the printing end portion of the wire. The ink supply guide is provided with an ink layer forming chamber and a cylinder portion for drawing ink into the wire guide hole.

A stepped portion is formed at a predetermined position on the wire to be slidably fitted into the cylinder portion from the ink layer forming chamber side. A structure is adopted in which the stepped portion on the wire is located within the area of the ink layer forming chamber when the wire is at rest, and located within the cylinder when the wire is in operation.

(Embodiments of the Invention) Hereinafter, a first embodiment of the present invention will be described based on FIGS. 1 and 2.

The print head device of the ink dot printer in this first embodiment has a main body part IA and a nose part IB, as shown in FIG. A plurality of electromagnetic magnets 2 for driving wires corresponding to the number of dots formed by the wires 6 are housed in the main body IA. Inside the nose portion IB, an ink supply guide 7 is disposed at the tip, and wire support guides 8, 9 are disposed at the middle. Each of the plurality of wires 6 is slidably supported by each of these guides 7.8 and 9. Each wire 6 has one end connected to an armature 3 driven by an electromagnetic magnet section 2 . Therefore, the wire 6 operates integrally with the operation of the armature 3. The other end of each wire 6 is arranged on the printing surface of the ink supply guide 7.

Specifically, each of the wires 6 is connected to an ink supply guide 7.
They are slidably supported in wire guide holes 7A formed in the wire guide holes 7A, and are arranged at predetermined intervals in the vertical direction of FIG. 1, with their printed ends facing the printed surface.

In this case, the wire guide hole 7A formed in the ink supply guide 7 is actually formed by a small guide hole 7a on the printing surface side and a normal guide hole 7b communicating with the inside of the nose portion IB. Each tip of the wire 6 also connects to the printing side small diameter portion 6a via the step portion 6C corresponding to the guide small hole portion 7a.
It has a two-stage structure including a normal diameter portion 6b and a normal diameter portion 6b.

As shown in FIG. 2, an ink tank 10 is disposed above the nose portion IB. The ink IOA in the ink tank 10 is guided to the ink supply guide 7 through a bendable vibrator 11.

As shown in FIG. 1, the ink supply guide 7 has an ink chamber 7B in the upper part and an ink layer forming chamber 7B in the wire support part.
It has C. The ink chamber 7B and the ink layer forming chamber 7C communicate with each other via an ink passage 7F which is formed narrowly. This ink passage 7F normally does not allow ink to pass through due to capillary action, and It allows ink to pass through only when pressure is applied.

The ink layer forming chamber 7C is formed by a thin plate-shaped ink filling gap that is perpendicular to the normal guide hole 7b portion of the wire guide hole 7A that supports the wire 6. The dimension in the thickness direction of the ink layer forming chamber 7C is set to such a thickness that the ink IOA is stopped from flowing down and held by its own surface tension.

The part of the normal guide hole 7b of the wire guide hole 7A, which is doubled by the ink layer forming chamber 7C, is connected to the guide small hole 7a on the printing surface side, forming a cylinder part 7d. The normal diameter portion 6b of the wire 6 described above is inserted into the cylinder portion 7d so as to have a piston function.

Here, the small diameter portion 6a of the wire 6 has a predetermined dot diameter necessary for printing, and is guided and slidably supported by the guide small hole portion 7a. When the wire 6 is at rest, the normal diameter portion 6b of the wire 6 is located in the ink layer forming chamber 7C or the normal guide hole 7b.

When the wire 6 moves to the right in FIG. 1 while the wire 6 is being driven, the normal diameter portion 6b of the wire 6 enters the cylinder portion 7d.

Next, the operation of the first embodiment will be explained.

When printing starts, the armature 3 is first driven by the electromagnetic magnet 2, and the wire 6 moves from the rest position to the printing position. At this time, the stepped portion 6C of the double structure of the wire 6 is connected to the piston head. The wire serves to forcibly push out the ink that has entered the cylinder portion 7d from the ink layer forming chamber 71 to the printing surface side through the gap between the small diameter portion 6a of the wire 6 and the guide small hole portion 7a. 6 returns to the rest position, the ink I in the ink layer forming chamber 7C
OA is drawn in through the ink passage 7F by negative pressure,
It flows into the cylinder portion 7d.

Therefore, in this embodiment, a certain amount of ink is forcibly pushed out to the tip of the wire 6.
The supply of ink to the tip of the wire 6 becomes reliable, and it becomes possible to apply a stable and constant amount of ink for dot printing to the dot printing part of the wire 6, which is different from mere adhesion of ink. Since it is a forced adhesion, clogging caused by external paper dust etc. can be almost completely eliminated, and an ink dot printer head with clear printing and high reliability can be provided. In addition, when the ink thermally expands, the pressure is dispersed because the ink layer forming chamber 7C has a relatively large thin plate shape, so that the pressure does not concentrate on the wire guide hole 7A.
Therefore, the flow of ink from the ink chamber 7B is temporarily suppressed.

As described above, since the first embodiment has various advantages, a printer using this eliminates the need for an ink ribbon and its feeding mechanism, and therefore has a simpler structure. This has the advantage that failures are significantly reduced and the entire device can be provided at a relatively low cost.

[Second example] Next, a second embodiment will be described based on FIG.

Here, the same reference numerals are used for the same constituent members as in the first embodiment described above.

In the embodiment shown in FIG. 3, the wire 6 has a two-stage structure at its tip, similar to the case shown in FIG. A small center hole 6h is provided in the small diameter portion 6a of the wire 6 along the central axis from the end surface thereof. This center small hole 6
In this embodiment, the depth of h is at least the step portion 6 of the wire 6.
There is a 0 part. A communication hole 6k is provided in a portion of the wire 6 near the stepped portion 6C to communicate the outer periphery of the wire 6 with the center hole 6h.

The other configurations are the same as those of the first embodiment described above.

Even in this case, in addition to having the same effect as the first embodiment described above, ink is applied to the printed end of the wire 6 through the communicating small hole 6 and the center small hole 6h to the cylinder portion 7.
This can be effectively performed in a state similar to direct ejection from inside the ink to the tip, which has the advantage of completely eliminating the occurrence of white characters due to ink smearing or the like.

〔Effect of the invention〕

Since the present invention is configured and functions as described above, it is possible to forcibly and reliably send liquid ink to the tip of the wire by the action of the ink layer forming chamber, the cylinder section, and the stepped section on the wire. Therefore, it is possible to provide an unprecedented and excellent printer head device that can almost completely eliminate accidents such as clogging caused by insufficient ink at the tip of the wire and contamination of paper dust.

[Brief explanation of the drawing]

FIG. 1 is an enlarged partial sectional view of a printer head device according to a first embodiment of the present invention, FIG. 2 is a partially sectional front view showing a printer head device equipped with the printer head device shown in FIG.
The figure is an enlarged partial sectional view showing the tip portion of the wire in the second embodiment. 2... Electromagnetic magnet part, 3... Armature, 6... Wire, 6a... Small diameter part of wire, 6C... Step part. , 6h...
・Center small hole, 6k...Communication small hole, 7...
...Ink supply guide, 7A...Guide hole, 7
C...Ink layer forming chamber, 7d...Cylinder section, 7F...Ink passage as means for supplying ink, 8, 9...Wire guide . Figure 1 [D

Claims (2)

[Claims] (1) A printer head device comprising a plurality of wires, an electromagnetic magnet unit that individually drives each wire via an armature, and a wire guide and an ink supply guide that slidably support each wire. The ink supply guide is disposed at the printed end portion of the wire, an ink layer forming chamber is provided in the ink supply guide, and a cylinder for drawing ink is inserted into the wire guide hole formed in the ink supply guide. A stepped portion is provided at a predetermined position on the wire and is slidably fitted into the cylinder portion from the ink layer forming chamber side. What is claimed is: 1. A printer head device, characterized in that the printer head device is located within the area of the layer forming chamber and is located within the cylinder when the wire is in operation. (2) A printer head device comprising a plurality of wires, an electromagnetic magnet unit that individually drives each wire via an armature, and a wire guide and an ink supply guide that slidably support each wire. The ink supply guide is disposed at the printed end portion of the wire, an ink layer forming chamber is provided in the ink supply guide, and a cylinder for drawing ink is inserted into the wire guide hole formed in the ink supply guide. A stepped portion is provided at a predetermined position on the wire and is slidably fitted into the cylinder portion from the ink layer forming chamber side. The wire is located within the region of the layer forming chamber and is located within the cylinder when the wire is in operation, and a center small hole is provided at the tip of the wire with a predetermined depth on the central axis from the tip of the wire. . A printer head device characterized in that the wire is provided with a communication hole that allows the center hole and the ink layer forming chamber to communicate with each other when the wire is at rest.