JPH08118719A - Multiple needle recording head - Google Patents

Abstract

PURPOSE: To prevent the short-circuit between first and second recording electrodes and to facilitate the decision of the continuity failure of a disconnection by eliminating the entangling between the first and second electrodes. CONSTITUTION: In a multiple needle recording head, first and second recording electrodes 1 and 2 are arranged in a zigzag state at a predetermined pitch, fixed by an electrode support block 5. Wires 6, 6 for forming the electrodes 1 and 2 are drawn from the block 5 and grouped. Then, each N pieces of the wires 6, 6 are gathered to one, wired to a circuit board 9, and then a separating member 11 is disposed between the wire 6 for forming the electrode 1 and the wire 6 for forming the electrode 2 when the group is connected to an external driving circuit.

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 an improvement in the connection structure of recording electrode needles of a multi-needle recording head to a wiring board.

[0002]

2. Description of the Related Art A multi-needle recording head used in an electrostatic recording system is, for example, as shown in FIGS. 4 and 5, two rows of wire rods 310 for recording electrodes arranged at high density with a constant pitch. Recording electrodes 101a and 101b, and control electrodes 102a and 102b composed of two columns of blocks corresponding thereto.
Are solidified by an electrode supporting block 103 such as an electrically insulating resin. Here, each recording electrode 1
01a and 101b are provided so as to be collectively connected to the drive circuit for each recording electrode that can be grouped in order to simplify the drive circuit (not shown). Therefore, the wire rods 310 are bundled for each group, and the binding portions 105 and 107 are bundled.
Are once connected to the wiring board 109 and then connected to the drive circuit for each group.

A multi-needle recording head having such a structure has a drum-shaped winding jig which has a groove for casting an electrically insulating resin on its surface and which can be wound with a wire material across the groove. A technique is known in which two of them are used to enable efficient production (JP-A-2-239953). As shown in FIG. 6, the winding jig 301 for winding is used for the control electrode 102.
a, 102b are set and resin casting grooves 305, 305 for pouring resin for the electrode support block, and a jetty portion 30 at the edge thereof so as to cross the resin casting grooves 305, 305
Recording electrode wire rod 31 formed on 6, 307, 308
, 309 for arranging 0 and 310 at a constant pitch, and pins 302 for hooking the wire rod 310 on both side wall surfaces of the winding jig 301 so that the wire rod 310 can be routed in any direction and position. It comprises 303 and 304. Resin casting groove 305 of the winding jig 301,
After setting the control electrodes 102a and 102b in the 305, the pins 30 on both sides outside the resin casting grooves 305 and 305
2, 303, 304 are sequentially entwined with one recording electrode wire 310, and continuously wound so as to cross the resin casting grooves 305, 305, and are bundled for each recording electrode belonging to the same group at a constant pitch. The M × N recording electrode wire rods 310 are stretched over the resin casting grooves 305, 305.

The wire rod 310 is wound around the winding jig 301 by reciprocating linear movement of the wire rod guide means 311 of the winding machine 312 in the axial direction (the direction shown by the arrow in FIG. 6) and the winding jig 301. Nozzle 3 of the wire rod guide means 311 while applying a certain amount of tension to the recording electrode wire rod 310 by a back tension mechanism (not shown) by utilizing the swinging or rotation of the nozzle 3.
It is carried out mechanically by pulling the wire rod 13 and hooking the wire rod 310 on the predetermined pins 302, 303, 304 and the wire rod holding grooves 309 ,.

The winding machine 312 shown in FIG.
Nozzle 313 for guiding the supply of the wire rod 310 to 01
And a first motor 315 for rotating a feed screw 314 for reciprocating the nozzle 313 along the winding jig 301, and swinging the winding jig 301 when winding the wire 310. And a second motor 316 for rotating, a control device 317 for controlling the first and second motors 315, 316, and the like.

Then, the wire rod 310 is butted against another winding jig 301 (not shown) around which the wire rod 310 is wound, and the two resin casting grooves 305, ...
The electrode support block 103 is formed by pouring resin into the space formed between the electrodes. Butt 3 for resin casting
05, ..., 305, the recording electrode wire 310 and the control electrodes 102a and 102b are arranged in the center in parallel with each other and in a fixed positional relationship, and the electrode support block 103 is formed around them. Resin is injected.

The wire rods 310, which are bundled in groups between the pins, are bundled by soldering. The bundling portions 105 and 107 bundled by soldering are then cut and removed from the pins 304, 303 and 302.
After that, the electrode support block 103 and the wire material 310 are removed from the winding jig 301, and the binding portions 105 and 107 are soldered to the terminals of the wiring board 109.

[0008]

However, in this wire connection structure, as shown in FIG. 5, when the wire rod 310 is detached from the pin of the winding jig 301, the wire rod 310 is released from the tensioned state, and the wire rod 310 is free from each tension. Since it shrinks in the direction, the overlapping of the wire rods becomes more complicated, the entanglement between the first wire rod 310 and the second wire rod 310 increases, and is there a disconnection even in the case of defective conduction or disconnection? It becomes difficult to determine whether or not there is a poor continuity, and it takes time to repair it. For example, when an attempt is made to search for a broken wire rod from one recording electrode group, the wire rod of the other recording electrode group is also entangled and pulled, so that the searching operation takes time. Further, a wire that has not been accidentally broken may be taken out to break a normal wire. Also,
Since there are spots X where the wire rods 310 of the first recording electrode 101a and the wire rods 310 of the second recording electrode 101b intersect each other, the first and second wire rods are damaged when the insulating coating of the wire rods is damaged. There is a possibility of causing a short circuit between them.

It is an object of the present invention to provide a multi-needle recording head that reliably prevents a short circuit between the first recording electrode side wire and the second recording electrode side wire. It is another object of the present invention to provide a multi-needle recording head in which the entanglement between the first recording electrode side wire and the second recording electrode side wire is eliminated. A further object of the present invention is to provide a multi-needle recording head with improved workability when removing the wire from the winding jig.

[0010]

To achieve the above object, the first aspect of the invention is to arrange the first recording electrodes and the second recording electrodes in a zigzag pattern at a constant pitch and harden them with an electrode support block. In the multi-needle recording head in which the wire rods forming the first and second recording electrodes are pulled out from the electrode support block and are collectively connected to the drive circuit for each group,
A separating member is arranged between the wire material that constitutes the first recording electrode and the wire material that constitutes the second recording electrode, which is pulled out from the electrode support block. Further, in the invention of claim 2, the separating member is made of an electric insulating material.

[0011]

Therefore, in the multi-needle recording head according to claim 1,
The wire member forming the first recording electrode and the wire member forming the second recording electrode are reliably separated by the separating member, and the wire members do not come into contact with each other. Further, in the multi-needle recording head according to claim 2, since the separating member is made of an electric insulating material,
Even if the insulation of the wire is broken, electrical insulation is surely performed.

[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.

1 and 2 show an embodiment of the multi-needle recording head of the present invention. This multi-needle recording head has no features in the basic structure of the electrode support block 5 itself including each electrode except for the structure of the wiring lead-out portion 12 between the electrode support block 5 and the wiring substrate 9. The conventional multi-needle recording head shown has the same head structure. This multi-needle recording head is also of the same surface control type, and has two rows of recording electrodes 1 and 2 and two corresponding rows of control electrodes 3 and 4 arranged at a high density with a constant pitch and electrically insulating resin. Electrode support block 5
Is hardened by. Further, the wire rods 6 and 6 forming each of the recording electrodes 1 and 2 are drawn out from the electrode support block 5, and are grouped by the recordable electrodes, that is, the wire rods 6 that can be grouped in order to simplify the drive circuit thereof. Then, the binding portion 7 is once connected to the wiring board 9, and thereafter,
Each group is provided so as to be connected to the drive circuit.

Here, as the wire 6 for the recording electrode, for example, a wire having an electrically insulating coating, for example, a wire coated with urethane is used. The wire rods 6 are pulled out from the electrode support block 5 and bundled in groups to form a wiring board 9
Be soldered to. Then, the first recording electrode 1 and the second
The separating member 11 is arranged at least between the portions of the respective wire rods 6 and 6 forming the recording electrode 2 that are drawn out from the electrode supporting block 5.

Incidentally, the separating member 11 is not particularly limited to the material, and the first recording electrode side wire 6 and the second recording electrode side wire 6 can be used.
It is sufficient if it can block the gap between the recording electrode side wire 6 and the recording electrode side wire 6, but if there is a possibility that the insulating coating of the wires 6 and 6 may be damaged, an insulating material or an insulating film is applied. Use is preferred. Further, as the separating member 11,
It is preferable to use a material having a dielectric constant lower than that of air.
Further, it is preferable to connect the wires 6 and 6 to the wiring board 9 in a form that does not cause tension, that is, in a loosened form as in this embodiment, in order to reduce the stray capacitance between the wires 6 and 6. .
With such a structure, the entanglement between the first and second recording electrode wire rods 6 and 6 is eliminated, and
The floating capacitance between the second recording electrode and the second recording electrode can also be reduced.

A multi-needle recording head having such a structure uses a winding jig as exemplified in FIG. 6, for example, to perform a winding method disclosed in Japanese Patent Laid-Open No. 2-239953, or a drawing method. Not another winding method (for example, Japanese Patent Application No. 5-216
897). For example,
A case where a single winding jig as shown in FIG. 3 is used will be described as an example. After the block of the control electrode 3 or 4 is arranged in the resin casting groove 22 of the winding jig 21, the wire rod holding groove formed in the jetty portions 23, 23 so as to cross the resin casting groove 22 (illustration) Wire rod 6 at a constant pitch using (omitted)
Wrap around. At this time, the wire rods 6 are sorted into groups by utilizing the pins 24, 25, 28 and 29 protruding around the winding jig 21 and bundled between the pins 26 and 27. For example, in the case of molding a head of 1 m at 400 dpi, there are 55 sets with 128 sets as one set, 7040 in total.
Each wire 6 is wound around each winding jig 21 and 21, and one wire serves as a first recording electrode and the other wire serves as a second recording electrode.

Next, as shown in FIG. 3, the two winding jigs 21 and 21 on which the wire 6 is wound are butted against each other via a spacer, and the resin casting grooves 22 and 22 are electrically insulating resin 30.
Is injected to harden the wire 6 to form the electrode support block 5. Then, the wire rods 6 divided into groups of N pieces (55 pieces) between the third pin 26 and the fourth pin 27 are
Bind by soldering. This soldering is performed manually or automatically.

Then, double-sided tapes 13 and 14 are attached to the fourth pins 27 side of the binding portions 7 and 8, and the double-sided tape 1 is further attached.
After the separation member 11 is attached to the sheet 3, the bundled binding portions 7 and 8 are cut. After that, for example, a bundle of the wire rods 6 of the one recording electrode 1 is first placed on one surface of the wiring substrate 9 with the separating member 11 attached, and the binding portion 7 is soldered to the terminal 10. After that, the wiring board 9 is turned over, the bundle of the wire rods 6 of the other recording electrode 2 is placed on the other surface, and the binding portion 8 is soldered to the terminal 10. In this way, the wires 6 and 6 and the separating member 11 have a structure in which the separating member 11 is centered and overlapped as shown in FIG. When the manufacturing method and structure of this embodiment are adopted, the separating member 11 has the double-sided tape 1 as shown in FIG.
It is sandwiched between 3, 14 and fixed, and double-sided tape 1
Due to the functions of 3, 14, the soldering work of the binding portions 7, 8 to the terminals 10 is extremely efficient, and the different recording electrodes 1,
It is performed without disconnection due to the entanglement of the wire rods 6 and 6 between the two. That is, it becomes possible to remove the wire rod 6 from the winding jig 21 without firmly fixing the wire rod 6 like a piece of cloth before removing the wire rod 6 from the winding jig 21. Even if it is removed from the pin 27 of 21 and the tension is released and it becomes loose and swelled, the double-sided tapes 13, 14
The binding portions 7 and 8 are fixed at predetermined positions by the action of, and the overlapping of the wire 6 with the separating member 11
Therefore, the work of soldering the binding portions 7 and 8 to the wiring board 9 can be performed very efficiently.

Further, this structure has different recording electrodes 1 and 2.
A constant space is secured between the two wire rods 6 and 6 between them and the separating member 11. Further, the wire rods 6 and 6 are connected in a tension-free form, that is, in a loosened form, as in the first embodiment. ing. For this reason, as shown in FIG. 2, the wire rod 6 of the wire routing portion 12 swells into a closed shape, and the stray capacitance is further reduced.

The above-described embodiments are examples of preferred embodiments of the present invention, but the present invention is not limited thereto and various modifications can be made without departing from the gist of the present invention. For example, the separating member 11 preferably has elastic film-like electrical insulation, but is not limited thereto. Although not shown, the electrode support block 5 may be molded by resin casting in two stages, and the end of the separating member 11 may be embedded in the electrode support block 5. In this case, in order to secure the pitch accuracy of the wire rod in the portion functioning as the recording electrode, the mold is cast to a depth of about half of the electrode support block 5 (primary casting). next,
The separating member 11 is inserted between the wire rods 6 and 6 between the first and second recording electrodes 1 and 2, and the wire rods 6 for both electrodes are pushed into the already solidified half of the electrode support block, and then left. Pour the resin in to perform the second casting. In the multi-needle recording head completed by this method, the separation member 11 is held by the electrode supporting block 5, and the portion which does not function as a recording electrode in the electrode supporting block 5 is loosened to reduce the floating capacitance between the wires 6 and 6. It becomes a structure to do.

[0021]

As is clear from the above description, in the multi-needle recording head according to the first aspect, the wire member forming the first recording electrode and the wire member forming the second recording electrode are reliably separated by the separating member. Since they are not separated and come into contact with each other, even if the insulating coating of the wire is damaged, a short circuit does not occur between the first and second wire. In addition, since the first and second wire members are completely separated without being entangled with each other, even when the recording electrode has poor continuity or disconnection, the first recording electrode side and the second recording electrode side are Since it is possible to clearly distinguish between the two, it is easy to determine and identify whether the disconnection is a poor conduction, and the repair work does not take time. Further, even when each wire rod is removed from the drum-shaped winding jig, the wire rod on the first recording electrode side and the wire rod on the second recording electrode side do not get entangled with each other, so that the work is easy.

Further, in the multi-needle recording head of the second aspect, since the separating member is made of the electric insulating material, the electric insulation is more surely performed and the short circuit can be surely prevented.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a multi-needle recording head of the present invention.

FIG. 2 is a cross-sectional view of the multi-needle recording head of the present invention.

FIG. 3 is an explanatory diagram showing an example of a method for manufacturing a multi-needle recording head according to the present invention.

FIG. 4 is a perspective view showing a conventional multi-needle recording head.

FIG. 5 is a cross-sectional view of a conventional multi-needle recording head.

FIG. 6 is a perspective view for explaining a winding method of a conventional multi-needle recording head.

[Explanation of symbols]

 1 1st recording electrode 2 2nd recording electrode 5 Electrode support block 6 Wire rod 7,8 Bundling part 9 Wiring board 10 Terminal 11 Separation member

Claims (2)

[Claims] 1. A first recording electrode and a second recording electrode are arranged in a zigzag pattern at a constant pitch and are solidified by an electrode supporting block, and the wire material constituting each of the first and second recording electrodes is formed by the electrode. In a multi-needle recording head that is pulled out from a support block and collectively connected to a drive circuit for each group, a wire rod that is pulled out from an electrode support block and that constitutes the first recording electrode and a wire rod that constitutes the second recording electrode. A multi-needle recording head, characterized in that a separating member is arranged between them. 2. The multi-needle recording head according to claim 1, wherein the separating member is made of an electrically insulating material.