JP2004063373A - Terminal connection method for micro coaxial cable assembly - Google Patents

Abstract

An object of the present invention is to provide a terminal connection method for a micro coaxial cable assembly which simplifies terminal connection of a center conductor of a micro coaxial cable and improves connection workability.
A collective connection pad (13) integrally formed with a plurality of rows of wirings (12a, 12b) is provided on a substrate (10), and a plurality of micro coaxial cables (52a, 52b) preliminarily soldered on the pad (13). Are separated from each other, and the jig 1 that covers the pads 13 and the central conductors 62a, 62b, and transmits the laser beams L1 and L4 is superposed on the pads 13 and the central conductors 62a, 62b. Irradiate the jig 1 with the laser beam L1, irradiate the center conductors 62a, 62b,... With the laser beam L1 transmitted through the jig 1 to melt the solder, and connect the pads 13 to the center conductors 62a, 62b,. Then, the pad 13 between the center conductors 62a, 62b,... Is cut by the laser light L4.
[Selection diagram] FIG.

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a terminal connection method for a micro coaxial cable assembly used for a medical ultrasonic diagnostic apparatus or the like.
[0002]
[Prior art]
The micro coaxial cable assembly is composed of a plurality of micro coaxial cables. As an example, there is a probe cable 51 as shown in FIG. 6 for connecting a main body of a medical ultrasonic diagnostic apparatus and a probe. .
[0003]
The probe cable 51 is composed of a plurality of micro coaxial cables 52 (16 in FIG. 6) to form a micro coaxial cable unit 53, and a plurality of micro coaxial cable units 53 (12 in FIG. 6). The outer periphery of the combined micro-coaxial cable unit 53 is covered with a sheath 54, the outer periphery of the sheath 54 is covered with a shield conductor 55, and the outer periphery of the shield conductor 55 is covered with a jacket 56.
[0004]
Although the structure is slightly different depending on the specifications of the cable, the number of micro coaxial cables used for one probe cable is about 50 at least and more than 2000 at most.
[0005]
As shown in FIG. 7, the micro coaxial cable 52 includes a plurality of conductors 61 (seven conductors in FIG. 7) to form a center conductor 62, and the outer periphery of the center conductor 62 is covered with an insulator 63. The outer periphery is covered with a shield conductor 64, and the outer periphery of the shield conductor 64 is covered with a jacket 65. For the central conductor 62, according to the American Electric Wire Standard, 44AWG (seven strands of a 20 μm conductor) to 46AWG (seven strands of a 16 μm strand) have become mainstream. The outer diameter a of the center conductor 62 is about 60 μm in the case of 44 AWG, and about 48 μm in the case of 46 AWG.
[0006]
The terminal connection of the probe cable 51 includes connection to the board on the apparatus main body side and connection to the board on the probe side. As can be seen from the fact that the center conductor 62 is extremely thin, it is a very labor-intensive operation. is there.
[0007]
The conventional method of connecting a terminal of a micro coaxial cable assembly is a method in which all operations are performed manually. First, the jacket 56, the shield conductor 55, and the sheath 54 at the end of the probe cable 51 are peeled off and the micro coaxial cable unit 53 is exposed. Thereafter, at the terminal of the micro coaxial cable 52 in the micro coaxial cable unit 53, the jacket 65, the shield conductor 64, and the insulator 63 are similarly peeled and removed, exposing the center conductor 62, and confirming conduction one core at a time. They were arranged in line with the wiring pitch of the board on the diagnostic device main body side and the probe side, and were manually soldered.
[0008]
[Problems to be solved by the invention]
However, in the conventional method, the terminal of the center conductor 62 of the micro coaxial cable 52 is connected to the FPC (FPC) because there is no appropriate jig for aligning the terminals of the plurality of micro coaxial cables 52 and connecting to the board. When connecting to a flexible printed circuit board) or a printed circuit board, alignment between the respective lines is also performed manually.
[0009]
At that time, if the center conductor 62 is hazy, it takes a long time to correct it, and there is a problem that the connection workability is poor. Further, as the wiring pitch is becoming narrower, the importance of alignment of the center conductor is increasing.
[0010]
Therefore, an object of the present invention is to provide a terminal connection method for a micro coaxial cable assembly that simplifies terminal connection of the center conductor of the micro coaxial cable and improves connection workability.
[0011]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and the invention of claim 1 relates to a method in which a plurality of micro coaxial cables to be connected to a plurality of micro coaxial cables to be connected thereto are peeled off from a plurality of lines formed on a substrate. In the method in which the center conductors are overlapped and welded, a collective connection pad integrally formed with the plurality of rows of wirings is provided on a substrate, and the plurality of micro coaxial cables preliminarily soldered are provided on the pads. The peeled center conductor is placed, and a jig that covers these pads and the center conductor and transmits laser light is superposed and aligned, and the jig is irradiated with laser light to irradiate the center conductor. The laser beam transmitted through the jig is irradiated to melt the solder, the pad and the center conductor are connected by soldering, and then the pad between the center conductors is cut with a laser beam. It is a method.
[0012]
According to a second aspect of the present invention, there is provided a method for superimposing and welding the separated central conductors of a plurality of micro coaxial cables to be connected to wirings formed in a plurality of rows on a substrate. A collective connection pad integrally formed with the wiring of the column is provided, and the separated center conductors of the plurality of micro coaxial cables are placed on the pad, and these pads and the center conductor are covered with these. A jig that transmits laser light is overlapped and aligned and held, and the jig is irradiated with laser light, and the pad and the center conductor are irradiated with laser light transmitted through the jig to partially melt the pad and the pad. This is a method for connecting a micro coaxial cable assembly in which a pad between the center conductors is cut with laser light after welding connection between the center conductor and the center conductor.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.
[0014]
First, a board suitable for terminal connection of the micro coaxial cable assembly will be described with reference to FIG. FIG. 1 is a plan view of an FPC as a connection board according to the present invention.
[0015]
As shown in FIG. 1, the substantially convex FPC 10 is provided on the diagnostic apparatus main body side or the probe side, and has a substantially band-shaped and flexible insulating film 11 and a flexible insulating film 11 formed on the insulating film 11. And wiring patterns.
[0016]
The wiring pattern has a wiring pitch P1 of 0.15 mm (upper side in FIG. 1) facing one edge of the insulating film 11 so as to be connected to the outside, and the other end facing the center of the insulating film 11. A plurality of lines for signal lines 12a, 12b... Formed in a plurality of rows with a wiring pitch P2 of 0.2 mm (the lower side in FIG. 1), and a plurality of lines are formed integrally with the other ends of these wires 12a, 12b. , A central central conductor collective connection pad 13 connected collectively to the separated central conductor of the micro coaxial cable, a ground strip-shaped wiring 14 formed along the wirings 12a, 12b,. A rectangular shield conductor collective connection pad 15 integrally formed at the other end of the wiring 14 along the central conductor collective connection pad 13 and connected collectively to the separated shield conductors of a plurality of micro coaxial cables. Going on.
[0017]
The other ends of the wirings 12a, 12b... And the pads 13 are orthogonal to each other, and the wirings 12a, 12b. The other end of the wiring 14 and the pad 15 are orthogonal to each other, and the entirety of the wiring 14 and the pad 15 are formed substantially in an L shape.
[0018]
FIG. 2 is a perspective view of a jig for aligning and connecting the micro coaxial cable terminals. FIG. 3 is a sectional view taken along line 3A-3A of the jig shown in FIG. FIG. 4 is a bottom view of the jig shown in FIG.
[0019]
As shown in FIGS. 2 to 4, the jig 1 for aligning and connecting the micro coaxial cable terminals according to the present invention is a probe mainly used in a medical ultrasonic diagnostic apparatus or the like as a micro coaxial cable assembly. The covering insulating material layer and the like of the plurality of micro coaxial cable terminals constituting the cable are superimposed on the removed central conductor.
[0020]
The jig 1 integrally covers and holds the center conductors, and places the aligned and held center conductors on central conductor collective connection pads provided on a board on the main body side or the probe side of the diagnostic apparatus. It is used when connecting.
[0021]
The jig 1 has a substantially rectangular jig main body 2 formed of quartz as a laser light transmitting material capable of transmitting laser light, and a center provided at the other end of a plurality of rows of wirings formed on a substrate. The conductor collective connection pad and the peeled center conductor of the plurality of micro coaxial cable terminals are welded and connected to each other by laser light.
[0022]
Also, on one surface of the jig body 2, a cross section as a groove portion which is superimposed on the peeled center conductors of a plurality of micro coaxial cable terminals and which integrally covers and holds the center conductors has a substantially U-shape. The U-shaped grooves 3a, 3b,... Are formed so that the U-shaped grooves 3a, 3b,... Are respectively formed along the lateral direction of the jig main body 2, and the adjacent U-shaped grooves 3a, 3b,. The main body 2 is formed to have a predetermined interval p along the longitudinal direction.
[0023]
The laser light transmitting material is not limited to quartz, and any material may be used as long as it transmits laser light and has a small attenuation of the transmitted laser light.
[0024]
The dimensions of the U-shaped grooves 3a, 3b,... Are the outer diameter of the center conductor (a described in FIG. 7), the shape of the wiring pattern connected to the central conductor collective connection pad on the substrate, and the wiring pitch of the wiring pattern (FIG. It may be determined according to P2) described in. For example, considering the fillet shape when the center conductor is soldered to the substrate, the maximum width w is about twice the outer diameter a of the center conductor, and the depth h is 1.5 to 2 times the outer diameter a of the center conductor. Preferably, the predetermined interval p is equal to the wiring pitch of the wiring pattern connected to the central conductor collective connection pads on the substrate.
[0025]
The U-shaped grooves 3a, 3b,... Are formed on one surface of the jig main body 2 by, for example, forming the jig main body 2 in a rectangular shape and then etching. By using the etching, the predetermined interval p can be set to a narrow pitch of less than 0.5 mm, for example, 0.3 mm or 0.2 mm, which is difficult to machine. The shape of the groove is not limited to the U-shaped grooves 3a, 3b, and may be, for example, a V-shaped groove having a substantially V-shaped cross section or a rectangular groove.
[0026]
As will be described later with reference to FIG. 5, when the central conductor and the central conductor collective connection pad on the substrate are soldered, for example, a fundamental wave of a YAG laser (wavelength: 1064 nm) is preferable. The wavelength is not limited to the fundamental wave of the YAG laser as long as it can melt.
[0027]
Further, as will be described later with reference to FIG. 5, when the central conductor and the central conductor collective connection pad are welded, for example, the second harmonic (532 nm wavelength) of a YAG laser is preferable as the wavelength of the laser beam. The wavelength is not limited to the second harmonic of the YAG laser as long as the wavelength can melt the center conductor.
[0028]
Further, as will be described later with reference to FIG. 5, when the center conductor is connected to the central conductor collective connection pads and then the central conductor collective connection pads between the respective center conductors are cut, as described later with reference to FIG. The fourth harmonic (wavelength 266 nm) is preferred, but the wavelength is not limited to the fourth harmonic of a YAG laser as long as the wavelength can cut the central conductor collective connection pad.
[0029]
Next, a method of connecting a terminal of the micro coaxial cable assembly will be described.
[0030]
FIG. 5 is a diagram illustrating a terminal connection method of a micro coaxial cable assembly using a connection board according to the present invention and a jig 1 for aligning and connecting micro coaxial cable terminals. As shown in FIG. 5, each micro coaxial cable 52a, 52b,... Connected to the FPC 10 is the same as the micro coaxial cable 52 described with reference to FIG.
[0031]
First, a connection method when the terminals of the central conductors 62a, 62b... And the central conductor collective connection pad 13 are soldered will be described.
[0032]
Prior to connection with the FPC 10, the jackets 65a, 65b,... Of the terminals of the micro coaxial cables 52a, 52b,..., The shield conductors 64a, 64b, and the insulators 63a, 63b. The shield conductors 64a, 64b are respectively exposed, and the stripped center conductors 62a, 62b... And the stripped shield conductors 64a, 64b... Are preliminarily soldered.
[0033]
The pre-soldered central conductors 62a, 62b,... Are placed on the central conductor collective connection pads 13 of the FPC 10, and these are inserted into the U-shaped grooves 3a, The jigs 1 for aligning and connecting the micro coaxial cable terminals with the U-shaped grooves 3a, 3b... Facing downward so as to cover 3b. The shield conductors 64a, 64b... Are located on the shield conductor collective connection pads 15.
[0034]
At this time, since the central conductor collective connection pad 13 on the FPC 10 also plays a role of positioning when the jigs 1 are stacked, even if the wiring pitch of the wirings 12a, 12b. , The center conductors 62a, 62b,... Can be easily aligned and held in alignment with the other ends of the wirings 12a, 12b,.
[0035]
.. And the pad 13 are irradiated with a fundamental wave L1 of a YAG laser from above the jig 1 to melt the solder, and the terminals of the center conductors 62a, 62b. Solder connection.
[0036]
Then, by irradiating the fourth harmonic L4 of the YAG laser from above the jig 1 to the pad 13 between the lines of the center conductors 62a, 62b,..., The portion is cut, and the center conductors 62a, 62b,. I do. Finally, when the shield conductors 64a, 64b,... And the pads 15 are separately soldered, the micro coaxial cables 52a, 52b,.
[0037]
Next, a connection method when the terminals of the central conductors 62a, 62b,... And the central conductor collective connection pad 13 are welded will be described.
[0038]
Similarly, the center conductors 62a, 62b,... Are exposed to form the separated center conductors 62a, 62b,..., And the separated center conductors 62a, 62b. The central conductors 62a, 62b,... Are aligned and held on the central conductor collective connection pads 13 so as to coincide with the other ends of the wirings 12a, 12b,.
[0039]
Here, the center conductors 62a, 62b,... Are irradiated with the second harmonic L2 of the YAG laser from above the jig 1 onto the pads 13 to melt the center conductors 62a, 62b,. The pads 13 are welded and connected together.
[0040]
In the FPC 10 according to the present invention, a central conductor collective connection pad 13 is formed. After connecting the central conductors 62a, 62b to the pad 13, the pad 13 between the central conductors 62a, 62b. Since the cutting is performed at the fourth harmonic L4, alignment and maintenance of the center conductors 62a, 62b... And terminal connection can be simplified.
[0041]
Further, in the jig 1 according to the present invention, since the U-shaped grooves 3a, 3b... Are formed in the jig main body 2, the center conductors 62a, 62b. Since the predetermined interval p between the U-shaped grooves 3a, 3b,... Can be a narrow pitch of less than 0.5 mm, which is difficult to machine, a narrow pitch line such as a 0.3 mm pitch or a 0.2 mm pitch can be used. It becomes possible.
[0042]
Since the jig body 2 is formed of quartz, the center conductors 62a, 62b,... Can be easily aligned and held while keeping the center conductors 62a, 62b,. Since the jig main body 2 is transparent, visibility during work can be improved.
[0043]
By using the FPC 10 and the jig 1 in this manner, the pre-soldered center conductors 62a, 62b... Can be easily aligned and held, and the center conductors 62a, 62b. By irradiating the wave L1, the terminals of the central conductors 62a, 62b... And the central conductor collective connection pad 13 are collectively connected by soldering, and the pad 13 between the central conductors 62a, 62b. Since the lines of the central conductors 62a, 62b are insulated by cutting with the wave L4, terminal connection of the central conductors 62a, 62b... Can be simplified, and connection workability can be improved.
[0044]
Therefore, the center conductors 62a, 62b,... Can be kept aligned and the terminal connection can be automated.
[0045]
The center conductors 62a, 62b... Which are not subjected to preliminary soldering are aligned and held by using the jig 1, and the center conductors 62a, 62b... Are irradiated with the second harmonic L2 of the YAG laser via the jig 1. Are connected to the terminals of the central conductors 62a, 62b,... And the central conductor collective connection pads 13 by welding, and the pads 13 between the central conductors are cut with the fourth harmonic L4 of the YAG laser to thereby form the central conductor 62a. , 62b... Are insulated, so that it is not necessary to use solder for connecting the center conductors 62a, 62b..., And the terminal connection of the center conductors 62a, 62b. be able to.
[0046]
Therefore, the center conductors 62a, 62b,... Can be kept aligned and the terminal connection can be automated.
[0047]
In this case, the terminals of the center conductors 62a, 62b,... Are melted and joined to the FPC 10, so that the mechanical and electrical reliability of the terminal connection is improved as compared with the case of soldering.
[0048]
In the above embodiment, the center conductors 62a, 62b,... Are placed on the FPC 10, and the jig 1 is overlapped with the center conductors 62a, 62b, so that the U-shaped grooves 3a, 3b. In the example described above in which the conductors 62a, 62b are aligned and held, the jig 1 is stacked on the FPC 10 so that the wirings 12a, 12b... And the U-shaped grooves 3a, 3b. The center conductors 62a, 62b... May be inserted into the 3a, 3b.
[0049]
Also, the jig 1 has the U-shaped grooves 3a, 3b... Facing upward, the center conductors 62a, 62b... Are mounted on the U-shaped grooves 3a, 3b, and the center conductors 62a, 62b. The FPC 10 may be mounted on the jig 1 to align and hold the center conductors 62a, 62b,. In this case, the central conductors 62a, 62b... And the central conductor collective connection pad 13 are irradiated with laser light from below the jig 1.
[0050]
【Example】
(Example 1)
The center conductor is exposed by peeling off the jacket, outer conductor, and inner insulator of the micro coaxial cable, preliminarily soldering the exposed center conductor, and using the jig 1 according to the present invention to collectively carry out the center conductor of the FPC 10. After aligning and holding the center conductor on the connection pad, and irradiating the center wave of the YAG laser from above the jig 1 to collectively solder the center conductor, the pad between the lines of the center conductor is connected to the YAG laser. Four harmonics were irradiated and cut, and each center conductor was insulated.
[0051]
(Example 2)
Similarly, the center conductor is exposed, the center conductor is aligned and held on the FPC 10 using the jig 1 according to the present invention, and the second harmonic of the YAG laser is irradiated from above the jig 1 to collectively center the center conductor. After the conductors were collectively welded, the pads between the lines of the center conductor were cut by irradiating the fourth harmonic of the YAG laser to insulate between the center conductors.
[0052]
(Comparative example)
Similarly, the center conductor was exposed, and as described in the prior art, the conductors were arranged one by one according to the wiring pitch of the substrate while confirming the continuity one by one, and soldered manually.
[0053]
Working accuracy and working time were investigated for the terminal processed products manufactured based on Examples 1 and 2 and Comparative Example. As a result, the working accuracy of each of Example 1 and Example 2 was equivalent to that of the comparative example, and the operation time was shorter than that of the comparative example. Also, the method of the comparative example was difficult unless a skilled worker, but the methods of Example 1 and Example 2 were possible even for beginners.
[0054]
【The invention's effect】
As is clear from the above description, the present invention exerts the following excellent effects.
[0055]
(1) The center conductor of the micro coaxial cable can be aligned and maintained, and the terminal connection can be mechanized and automated.
[0056]
(2) Terminal connection of the center conductor of the micro coaxial cable can be simplified, and connection workability can be improved.
[0057]
(3) The center conductor can be connected to the substrate without using solder. In this case, since the terminal of the center conductor is melted and joined to the substrate, the mechanical and electrical reliability of the terminal connecting portion is improved.
[Brief description of the drawings]
FIG. 1 is a plan view of a substrate according to the present invention.
FIG. 2
It is a perspective view of a jig concerning the present invention.
FIG. 3
FIG. 3 is a sectional view taken along line 3A-3A of the jig shown in FIG. 2.
FIG. 4
FIG. 3 is a bottom view of the jig shown in FIG. 2.
FIG. 5 is a diagram illustrating a terminal connection method of the micro coaxial cable assembly according to the present invention.
FIG. 6 is a sectional view of a probe cable.
FIG. 7 is a sectional view of a micro coaxial cable.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Jig 2 Jig main body 3a, 3b ... U-shaped groove 10 FPC (substrate)
12a, 12b... Wiring for signal line 13 Pad for central conductor collective connection L1 Fundamental wave of YAG laser L2 Second harmonic of YAG laser L4 Fourth harmonic of YAG laser

Claims (2)

In a method in which a plurality of micro-coaxial cables to be connected to the wiring formed in a plurality of rows on a substrate are overlapped and welded and connected to each other, the plurality of micro-coaxial cables are integrally formed with the plurality of rows of wirings on the substrate. A plurality of pads for collective connection are provided, and the center conductors of the plurality of micro coaxial cables, which have been pre-soldered in advance, are placed on the pads, and the pads and the center conductor are covered with a laser beam. The jigs that transmit the jig are overlapped and held in alignment, and the jig is irradiated with laser light, the center conductor is irradiated with the laser light transmitted through the jig to melt the solder, and the pad and the center conductor And connecting the pads between the center conductors with a laser beam after soldering. In a method in which a plurality of micro-coaxial cables to be connected to the wiring formed in a plurality of rows on a substrate are overlapped and welded and connected to each other, the plurality of micro-coaxial cables are integrally formed with the plurality of rows of wirings on the substrate. A jig for placing the separated central conductors of the plurality of micro coaxial cables on the pads, and covering these pads and the central conductor to transmit the laser light over the pads and the central conductor. The jig is irradiated with laser light, the pad and the center conductor are irradiated with laser light transmitted through the jig to partially melt the jig, and the pad and the center conductor are welded and connected. And then cutting the pad between the center conductors with a laser beam.

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