JPH07148967A - Multi-needle record head - Google Patents

Abstract

PURPOSE:To obtain a multi-needle record head capable of suppressing floating or cutting of a conductive wire and breaking of the insulation coating by a method wherein a tensile strength of the conductive wire of the multi-needle record head formed by being detached from a winding jig is set in a specific range. CONSTITUTION:A conductive wire to be a record needle is wound around a winding jig having straight section in a cross sectional circumference in such a manner that the wire is stringed and wound at least to the straight section in a prescribed pitch to be cured together with an auxiliary electrode by a resin and to be detached therefrom, thus forming a multi-needle record head. In this head, a tensile strength of the conductive wire is set in a range of 30kg/mm<2>. When the tensile strength is lower than 30kg/mm<2>, cutting of the wire due to the tension applied on the conductive wire in the winding action is markedly generated. When greater than 50kg/mm<2>, floating thereof is easily generated and a problem of breaking of a coating thereof easily occurs. The tensile strength may be preferably set in a range of 35kg/mm<2>-45kg/mm<2>. When taking the value of the tensile strength in the range, the conductive wire for the record electrode is deformed along a shape of the winding jig, so that the floating is not generated in a record electrode structure section and it can be wound around the winding jig being adhered thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-needle recording head suitable as an electrostatic recording type recording head. More specifically, the present invention relates to improvements in recording electrodes of a multi-needle recording head.

[0002]

2. Description of the Related Art A multi-needle recording head used in an electrostatic recording system, for example, a double-sided control type multi-needle recording head, is shown in FIG. Recording electrodes 101a and M.times.N second recording electrodes 101b arranged in parallel with the recording electrodes 101a at a predetermined interval are arranged at a high density with a constant pitch, and the respective end surfaces are exposed to electrically It is fixed by an electrode support block 103 such as an insulating resin. First and second recording electrodes 101
In order to simplify the driving circuit, a and 101b are arranged once for each wiring electrode which can be grouped and are once arranged on the wiring substrate 10.
4 and the wiring patterns on the wiring board 104 are used to connect to the drive circuit for each group. For example, the first and second recording electrodes 101a,
One of the terminals 101b of the wiring board 104 is formed by collecting N conductive wires (hereinafter, referred to as recording electrode conductive wires or simply conductive wires) 101, each of which constitutes a recording electrode belonging to the same group from N recording electrode groups. , 105m are integrated into M terminals 105a, ..., 105m.

As a method of efficiently manufacturing such a multi-needle recording head in a state in which the recording electrode lead wires are classified for each group, a multi-needle recording jig 301 as shown in FIG. 5 is used. A technique for manufacturing a recording head has been previously proposed by the present inventors (JP-A-2-239953).
issue). The winding jig 301 used in this manufacturing method has a prismatic shape with a substantially octagonal cross section, and a cavity groove 305 is provided on one surface of which the control electrode 102a (or 102b) is set and resin is poured. The recording electrode lead wires are tensioned at a constant pitch so as to cross the cavity groove 305, and the periphery thereof is solidified with resin.

The winding jig 301 is provided with conductive wire holding grooves 309 for arranging the conductive wires 101 on the jetty portions 306, 307, 308 at the edge of the cavity groove 305 at a constant pitch, and on both side wall surfaces of the winding jig 301. It is provided with an orientation pin 302, a bundling pin 303, and a turn pin 304 for hooking the conductive wire 101 and allowing it to be routed in an arbitrary direction and position. Cavity groove 305 of this winding jig 301
After setting one control electrode 102a or the like in the inside, connect one continuous conductive wire 101 to the pins 302, 303, 3 on both sides.
No. 04 is alternately entwined and continuously wound so as to cross the cavity groove 305, and the conducting wires 101 of the recording electrodes belonging to the same group are entwined with the same bundling pin 303 and turn pin 304 so as to be M × N-th at a constant pitch. The conductor wire 101 that constitutes one recording electrode 101a is stretched. At this time, back tension is applied to the winding machine 310 because the pitch cannot be guaranteed unless the conductive wire 101 is held with a uniform tension.

Similarly, the other control electrode and the second recording electrode conducting wire are set on the other winding jig (not shown). Then, the pair of winding jigs are butted against each other, and the cavity grooves 305, 3 of the two winding jigs 301 facing each other are formed.
Resin is poured into one space constituted by the groove 05 to form the electrode support block 103, and the cavity groove 305,
The recording electrode conducting wire 101 that crosses 305 is solidified to form the first and second recording electrodes 101a and 101b with a fixed positional relationship.

Therefore, each jetty portion 306, 307, 3
The pitch of the conducting wire holding grooves 309, ..., 309 of No. 08 influences the pitch of the recording electrodes 101a and 101b, and each conducting wire holding groove 309 ,.
It is important to ensure that the conductor wire 101 is fitted in the wire 309, and a highly accurate wire is required.

[0007]

However, no matter how high the accuracy of the winding jig is prepared, the arrangement relationship of the recording electrode lead wires 101 may be misaligned, resulting in a problem that the staggered arrangement cannot be performed. there were. As a result of various studies conducted by the present inventors on this point, the winding jig 3 having an angular shape
When the lead wire 101 for the recording electrode is wound around 01, the lead wire 101 cannot be deformed along the shape of the winding jig 301 if the lead wire 101 has a high tensile strength like a general nickel wire as the lead wire 101 for the record electrode. It has been found that there is a possibility that the recording electrode conductive wire 101 does not enter the conductive wire holding groove 309 of the jig 301 and floats. In particular, in the case of a two-piece winding jig in which the portions forming the recording electrodes 101a and 101b are arranged in the center of the jig, the lead wire 101 is remarkably lifted and vertically displaced. Or the slack is generated as shown in FIG. 7 and the linearity of the conductive wire 101 (deviation in the left-right direction) is deteriorated. Therefore, as shown in FIG. 8, the upper and lower die winding jigs 30
Recording electrode lead wires 101 respectively wound around 1, 301,
The staggered arrangement relationship of 101 is distorted, and when the head is used, the staggered arrangement relationship between the first recording electrode 101a row and the second recording electrode 101b row is distorted as shown in FIG. This may lead to poor electrode accuracy. This poor electrode accuracy has a problem in that dot unevenness occurs during printing. Furthermore, when the tensile strength of the conductive wire 101 is high, the insulating coating may be damaged at the edge portion of the nozzle of the winding machine.

On the other hand, when a conductor wire having a low tensile strength, such as a copper wire, is used in order to make sure that the wire jig is tightly wound around a predetermined position at a predetermined pitch, the wire breaks due to back tension. May occur.

According to the present invention, when winding the recording electrode conducting wire at a constant pitch using a winding jig having a straight cross-section outer periphery, the conducting wire is not lifted or broken, and the insulation coating is not damaged. An object is to provide a multi-needle recording head.

[0010]

In order to achieve the above object, the present invention provides a winding jig having a straight portion at the outer circumference of a cross section, and a conductor wire serving as a recording electrode is wound around at least the straight portion at a predetermined pitch. After that, harden it with resin together with the auxiliary electrode,
In the multi-needle recording head formed by removing from the winding jig, the tensile strength of the conductive wire is 30 kg / mm ^{2 to} 50 kg / m.
The range is set to m ² . Tensile strength is 30k
If it is lower than g / mm ² , the tension applied to the conductor wire during winding may cause a rapid disconnection, resulting in 50 kg /
If it exceeds mm ² , the conductor may start to float and the coating may be easily damaged. More preferably, the tensile strength is set to ^{35kg / mm 2 ~45kg / mm 2} .

[0011]

When the tensile strength in the above range is taken, the recording electrode conductor wire is deformed along the shape of the winding jig, and moreover, it is adhered to the winding jig without causing a rise in the portion constituting the recording electrode. Can be wrapped around. Also, the tension during winding does not cause disconnection.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described in detail below with reference to the embodiments shown in the drawings. In the multi-needle recording head of the present invention, the structure and manufacturing method of the head itself are not particularly important, and therefore detailed description thereof will be omitted.

The present invention is disclosed in a winding jig having a linear portion on the outer periphery in cross section, for example, a winding jig as shown in FIG. 5 previously proposed by the present inventor or Japanese Patent Application No. 4-291941. At least the recording electrodes 101a, 1 of the wound winding jig
01b, one continuous conductive wire 101 to be the recording electrodes 101a and 101b is wound around the linear portion having the cavity groove 305 for casting a resin at a predetermined pitch, and then hardened with a resin together with the auxiliary electrode. When applied when creating a multi-needle recording head as shown in FIG. 4, the manufacturing efficiency is greatly improved. Regarding the manufacturing method and the head structure, for example, JP-A-2-79953 or Japanese Patent Application No. 4-291941 can be referred to.

Here, the conductor is not limited to Ni or Cu as its material, and its tensile strength is 30 kg.
/ Mm ^{2 to} 50 kg / mm ² , more preferably 35 kg
/ Mm ^{2 to} 45 kg / mm ² of conductive material may be used. That is, as shown in FIG. 1, the tensile strength of the conductor wire is 45 kg / mm.
^{When the number of} wires exceeds ² , the conductor 101 starts to float, especially 50
If it exceeds kg / mm ² , the conductor may float, which is a practical problem for a multi-needle recording head. Moreover, the same applies to damage to the insulating coating of the conductive wire 101 as shown in FIG. Further, as shown in FIG. 2, when the tensile strength becomes lower than 35 kg / mm ² , wire breakage starts to occur due to the tension applied to the conductor wire during winding, and when it becomes lower than 30 kg / mm ² , wire breakage easily occurs rapidly. . Also, the conductor 101
The insulating coating is also not particularly limited, and is, for example, urethane coating.

It should be noted that the above-mentioned embodiment is an example of the preferred embodiment of the present invention, but the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention.

[0016]

As is apparent from the above description, the multi-needle recording head of the present invention has a tensile strength of a conductive wire of 30 kg / mm ^2.
Since it is set in the range of up to 50 kg / mm ^2, the wire for the recording electrode can be easily deformed along the shape of the winding jig to prevent the recording electrode from being lifted up in the winding jig. While tightly wound, the tension does not cause wire breakage. In addition, the insulating coating of the conductor is not damaged.

[Brief description of drawings]

FIG. 1 is a graph showing a relationship between a conductor tensile strength and a conductor float.

FIG. 2 is a graph showing the relationship between the tensile strength of a conductive wire and the number of breaks in the conductive wire (per head).

[Fig. 3] Conductor tensile strength and number of coating damages (per head)
It is a graph which shows the relationship with.

FIG. 4 is a perspective view showing an example of a multi-needle recording head.

5 is a perspective view showing an example of a winding jig for manufacturing the multi-needle recording head of FIG.

FIG. 6 is a front view for explaining a state where a conductor wire floats on a winding jig.

FIG. 7 is a plan view illustrating a state in which the linearity is deteriorated due to the floating wire on the winding jig.

FIG. 8 is a schematic diagram for explaining pitch irregularity of the recording electrode conductor when the conductor floats on the winding jig.

FIG. 9 is a schematic diagram for explaining an electrode precision defect when the conductor wire floats on the winding jig.

[Explanation of symbols]

 101 Lead wire for recording electrode 301 Winding jig

Claims (1)

[Claims] 1. A winding jig having a straight portion on the outer circumference of a cross section, a conductive wire serving as a recording electrode is erected and wound around at least the straight portion at a predetermined pitch, and then hardened with a resin together with an auxiliary electrode. In the multi-needle recording head formed by detaching from the tool, the tensile strength of the lead wire is 30 kg / mm ²
A multi-needle recording head having a weight of -50 kg / mm ² .