This application claims priority from Japanese Patent Application No. 2018-113124 filed on Jun. 13, 2018, the entire contents of which are incorporated herein by reference.
The present invention relates to an inner conductor terminal and a coaxial cable terminal unit using the inner conductor terminal.
Description of Related Art
A coaxial cable terminal unit is widely known in the related art, which includes an inner conductor terminal that is connected to a mating terminal and is conductively connected to an inner conductor of a coaxial cable, a dielectric that accommodates and retains the inner conductor terminal, and an outer conductor terminal that is internally provided with the dielectric and is conductively connected to an outer conductor of the coaxial cable.
When such a coaxial cable terminal unit is used as, for example, a terminal of an antenna wire (coaxial cable) for an in-vehicle radio, a technique of mounting a chip-type electronic element on an inner conductor terminal is known (see, for example, Patent Document 1: JP-A-2004-71208). For example, a chip capacitor for adjusting electrostatic capacity and improving noise resistance is mounted as the electronic element.
Specifically, the inner conductor terminal described in the above document is separately provided with a connection terminal at a tip end portion that is connected to a mating terminal, and a crimping terminal at a base end portion that crimps the inner conductor of the coaxial cable. The chip-type electronic element is mounted on a base end portion of the connection terminal and a tip end portion of the crimping terminal by soldering, so as to couple the base end portion of the connection terminal with the tip end portion of the crimping terminal in a separated state. In order to protect the chip-type electronic element, peripheries of the base end portion of the connection terminal, the tip end portion of the crimping terminal, and the chip-type electronic element are covered with a molded portion formed of resin.
[Patent Document 1] JP-A-2004-71208
In the inner conductor terminal described in the above document, the adhesion force in adhesion portions is relatively small. The adhesion portions are respectively located between the molded portion formed of resin and the base end portion of the connection terminal formed of metal, and between the molded portion formed of resin and the tip end portion of the crimping terminal formed of metal. Therefore, when an external force is applied to either or both of the connection terminal and the crimping terminal constituting the inner conductor terminal during insertion of the mating terminal or routing to the vehicle, the external force is likely to transmit to solder that connects and fixes the base end portion of the connection terminal and the tip end portion of the crimping terminal to the chip-type electronic element. As a result, an excessive stress acts on the solder, which may reduce reliability of electrical connection via soldering.
One or more embodiments provide an inner conductor terminal, which can maintain good electrical connection reliability and is provided with a chip-type electronic element, and a coaxial cable terminal unit using the inner conductor terminal.
In an aspect (1), one or more embodiments provide an inner conductor terminal including a connection terminal, a crimping terminal, a chip-type electronic element, and a molded portion. The connection terminal includes a connection portion that is connected to a mating terminal at a tip end portion thereof. The crimping terminal includes an inner conductor crimping portion that crimps an inner conductor of a coaxial cable at a base end portion thereof. The chip-type electronic element is mounted on a base end portion of the connection terminal and a tip end portion of the crimping terminal so as to couple the base end portion of the connection terminal with the tip end portion of the crimping terminal. The molded portion covers peripheries of the base end portion of the connection terminal, the tip end portion of the crimping terminal, and the chip-type electronic element. At least one of the base end portion of the connection terminal and the tip end portion of the crimping terminal includes a convex portion or a recessed portion on a surface thereof. The molded portion covers a periphery of the convex portion or enters the recessed portion.
In an aspect (2), each of the base end portion of the connection terminal and the tip end portion of the crimping terminal has a flat-plate shape. The recessed portion includes a through hole penetrating in a plate thickness direction. The inside of the through hole is filled with the molded portion.
In an aspect (3), the through hole includes a protruding portion extending from an inner wall surface of the through hole toward a radially inner side.
In an aspect (4), a coaxial cable terminal unit includes the inner conductor terminal according to any one of the aspects (1) to (3), a dielectric, and an outer conductor terminal. A terminal accommodation chamber accommodating and retaining the inner conductor terminal is formed through the dielectric. The outer conductor terminal includes a shell portion internally provided with the dielectric at a tip end portion thereof and an outer conductor crimping portion crimping an outer conductor of the coaxial cable at a base end portion thereof.
According to the aspect (1), the molded portion covers the periphery of the convex portion provided on a surface of the base end portion and/or a surface of the tip end portion of the crimping terminal, and/or enters the recessed portion. Therefore, when an external force is applied to the inner conductor terminal, a part of the external force is received by a portion adhered to a lateral surface of the convex portion and/or a lateral surface of the recessed portion in the molded portion. As a result, compared with the case where the convex portion and the recessed portion are not provided, an excessive stress is less likely to act on an electrical connection portion (typically solder) that connects and fixes the base end portion of the connection terminal and the tip end portion of the crimping terminal to the chip-type electronic element. Accordingly, it is easy to favorably maintain the reliability of the electrical connection.
According to the aspect (2), the inside of the through hole is filled with the molded portion. Therefore, when an external force (in particular, a tensile force or a compressive force along the axial direction) is applied to the inner conductor terminal, a part of the external force can be received by a portion adhered to an inner wall surface of a through hole in the molded portion. As a result, an excessive stress is less likely to act on the electrical connection portion. Accordingly, it is easy to favorably maintain the reliability of the electrical connection.
Further, when the soldering is performed by a reflow method that is an electrical connection method, a part of molten solder drops, due to the action of gravity, through the through hole, even when an excessive amount of solder paste is placed on the mounting surfaces for the chip-type electronic element on the base end portion of the connection terminal and the tip end portion of the crimping terminal. Therefore, it is easy to properly maintain the amount of solder used for electrical connection.
According to the aspect (3), it is easy to favorably maintain the reliability of the electrical connection not only when a tensile force or a compressive force along the axial direction is applied to the inner conductor terminal, but also when a bending moment, which is in a direction in which one of the connection terminal and the crimping terminal is rotated with respect to the other one of the connection terminal and the crimping terminal around the axis of one of the through holes, is applied to the inner conductor terminal. That is, when such a bending moment is applied to the inner conductor terminal, a part of the bending moment is received by the portion adhered to a lateral surface of the protruding portion in the molded portion. As a result, an excessive stress is less likely to act on the electrical connection portion, compared with the case where the protruding portion is not provided on the inner wall surface of the through hole. Accordingly, it is easy to favorably maintain the reliability of the electrical connection.
According to the aspect (4), the molded portion covers the periphery of the convex portion, which is provided on a surface of the base end portion of the connection terminal and/or a surface of the tip end portion of the crimping terminal, and/or enters the recessed portion. Therefore, when an external force is applied to the inner conductor terminal, a part of the external force acts on a portion adhered to a lateral surface of the convex portion and/or a lateral surface of the recessed portion in the molded portion. As a result, compared with the case where the convex portion and the recessed portion are not provided, an excessive stress is less likely to act on an electrical connection portion (typically solder) that connects and fixes the base end portion of the connection terminal and the tip end portion of the crimping terminal to the chip-type electronic element. Accordingly, it is easy to favorably maintain the reliability of the electrical connection.
According to one or more embodiments, it is possible to provide an inner conductor terminal, which can maintain good electrical connection reliability and is provided with a chip-type electronic element, and a coaxial cable terminal unit using the inner conductor terminal.
The present invention has been briefly described as above. Details of the present invention is clarified by reading a mode for carrying out the present invention described below with reference to the accompanying drawings.
An inner conductor terminal 10 according to the embodiment of the present invention and a coaxial cable terminal unit 1 using the inner conductor terminal 10 will be described with reference to the drawings. For convenience of description, in an axial direction of the terminal unit 1, a side (left side in
As illustrated in
An antenna wire for an in-vehicle radio is typically assumed as the coaxial cable 80 that is connected to the terminal unit 1. Therefore, a chip-type electronic element 60 for adjusting electrostatic capacity and improving noise resistance is mounted on the inner conductor terminal 10 used for the terminal unit 1. Hereinafter, components constituting the terminal unit 1 will be described in order.
First, the inner conductor terminal 10 is described. The inner conductor terminal 10 has a function of being connected to the mating terminal (not illustrated), and being conductively connected to the inner conductor 81 of the coaxial cable 80. As illustrated in
The connection terminal 40 formed of metal includes, at a tip end portion thereof, a cylindrical connection portion 41 that is connected to the mating terminal. The mating terminal (male terminal) is inserted into a hollow portion (through hole) of the connection portion 41. A base end portion 42 of the connection terminal 40 has a flat-plate shape (strip shape) extending in the axial direction. A through hole 43 (in particular, see
The crimping terminal 50 formed of metal includes, at a base end portion thereof, an inner conductor crimping portion 51 that is formed by a pair of crimping pieces for crimping the inner conductor 81 of the coaxial cable 80. A tip end portion 52 of the crimping terminal 50 has a flat-plate shape (strip shape) extending in the axial direction. A through hole 53 (in particular, see
The chip-type electronic element 60 is mounted on the mounting surfaces of the base end portion 42 and the tip end portion 52 so as to couple the base end portion 42 with the tip end portion 52. The base end portion 42 of the connection terminal 40 and the tip end portion 52 of the crimping terminal 50 are spaced apart from each other by a predetermined distance and disposed to face each other in the axial direction. More specifically, between the pair of electrode portions 61 provided on both sides of the chip-type electronic element 60, one electrode portion 61 is mounted on the mounting surface of the base end portion 42 by soldering, and the other electrode portion 61 is mounted on the mounting surface of the tip end portion 52 by soldering. In this way, the chip-type electronic element 60 electrically connects the base end portion 42 of the connection terminal 40 with the tip end portion 52 of the crimping terminal 50 in series. A chip capacitor is typically mounted as the chip-type electronic element 60. Alternatively, a chip resistor, a chip diode, a chip inductor, or the like may be mounted as the chip-type electronic element 60.
The molded portion 70 is a molded body formed of resin, which covers the peripheries of the base end portion 42 of the connection terminal 40, the tip end portion 52 of the crimping terminal 50, and the chip-type electronic element 60 so as to be adhered to the entire outer periphery thereof. The molded portion 70 mainly has a function of protecting the chip-type electronic element 60. The configuration of the inner conductor terminal 10 has been described above. The manufacturing method of the inner conductor terminal 10 will be described below.
Next, the dielectric 20 will be described. The dielectric 20 has a function of accommodating and retaining the connection terminal 40 of the inner conductor terminal 10 and being accommodated and retained in the outer conductor terminal 30 to maintain the inner conductor terminal 10 and the outer conductor terminal 30 in an insulated state. As illustrated in
Next, the outer conductor terminal 30 is described. The outer conductor terminal 30 has a function of accommodating and retaining the dielectric 20 and conductively being connected to the outer conductor 83 of the coaxial cable 80. As illustrated in
The mating terminal (male terminal) is inserted into an opening 34 on a tip side of the shell portion 31. The outer conductor crimping portion 32 includes: a pair of crimping pieces 35, which are located at a tip side and crimp the outer conductor 83 of the coaxial cable 80; and a pair of crimping pieces 36, which are located at a base end side and crimp the outer sheath of the coaxial cable 80. The accommodation portion 33 includes a bottom wall and a pair of side walls, and has a box shape whose top is opened.
The components constituting the terminal unit 1 illustrated in
As illustrated in
Next, the manufacturing method of the inner conductor terminal 10 illustrated in
Next, as illustrated in
A reflow method is typically adopted as a method of soldering. When the reflow method is adopted, a part of molten solder drops, due to the action of gravity, through the through holes 43 and 53 respectively formed in the base end portion 42 and the tip end portion 52, even when an excessive amount of solder paste is placed on the mounting surfaces of the base end portion 42 of the connection terminal 40 and the tip end portion of the crimping terminal 50. Therefore, it is easy to properly maintain the amount of solder used for electrical connection.
Next, as illustrated in
Next, the pair of bridge portions 90 connecting the connection terminal 40 with the crimping terminal 50 are cut and removed. Accordingly, the inner conductor terminal 10 illustrated in
As illustrated in
First, a mode is assumed as a comparative example to describe the actions and effects. In the mode, as illustrated in
In general, an adhesion force in adhesion portions is relatively small. The adhesion portions are respectively located between the molded portion 70 formed of resin and the base end portion 42 of the connection terminal 40 formed of metal, and between the molded portion 70 formed of resin and the tip end portion 52 of the crimping terminal 50 formed of metal. Therefore, in the comparative example, when a compressive force along the axial direction is applied to the inner conductor terminal 10 as indicated by an arrow in
In contrast, as illustrated in
As described above, according to the inner conductor terminal 10 and the terminal unit 1 of the embodiment of the present invention, the insides of the through holes 43 and 53 (recessed portions), which are respectively provided at the base end portion 42 of the connection terminal 40 and the tip end portion 52 of the crimping terminal 50, are integrally filled with the molded portion 70. Therefore, when an external force (in particular, a tensile force or a compressive force along the axial direction) is applied to the inner conductor terminal 10, a part of the external force is received by the portion 71 adhered to the inner wall surface of the through hole 43 and the portion 72 adhered to the inner wall surface of the through hole 53 in the molded portion 70 (see
Further, when the soldering is performed by the reflow method, a part of molten solder drops, due to the action of gravity, through the through holes 43 and 53, even when an excessive amount of solder paste is placed on the mounting surfaces of the base end portion 42 of the connection terminal 40 and the tip end portion 52 of the crimping terminal 50. Therefore, it is easy to properly maintain the amount of solder used for electrical connection.
The present invention is not limited to the above-described embodiment, and various modifications can be adopted within the scope of the present invention. For example, the present invention is not limited to the above-described embodiment, but can be appropriately modified, improved, and the like. In addition, materials, shapes, dimensions, numerals, disposition locations or the like of constituent elements in the above-described embodiment are optional and not limited as long as the object of the present invention can be achieved.
In the above embodiment, the through holes 43 and 53 (recessed portions) are formed in the base end portion 42 of the connection terminal 40 and the tip end portion 52 of the crimping terminal 50, respectively. The inside of the through hole 43 is integrally filled with the portion 71 of the molded portion 70, and the inside of the through hole 53 is integrally filled with the portion 72 of the molded portion 70 (see
In the present embodiment, when an external force (in particular, a tensile force or a compressive force along the axial direction) is applied to the inner conductor terminal 10, a part of the external force is also received by the portion 71 adhered to an inner wall surface of the notch 44 and the portion 72 adhered to an inner wall surface of the notch 54 in the molded portion 70. As a result, an excessive stress is less likely to act on the solder H (see
Further, as illustrated in
In the present embodiment, when an external force (in particular, a tensile force or a compressive force along the axial direction) is applied to the inner conductor terminal 10, a part of the external force is also received by the portion 71 adhered to a lateral surface of the convex portion 45 and the portion 72 adhered to a lateral surface of the convex portion 55 in the molded portion 70. As a result, an excessive stress is less likely to act on the solder H (see
Further, as illustrated in
In the present embodiment, it is easy to favorably maintain the reliability of the electrical connection not only when a tensile force or a compressive force along the axial direction is applied to the inner conductor terminal 10, but also when a bending moment, which is in a direction in which one of the connection terminal 40 and the crimping terminal 50 is rotated with respect to the other one of the connection terminal 40 and the crimping terminal 50 around the axis of one of the through holes 43 and 53, is applied to the inner conductor terminal 10. That is, when such a bending moment is applied to the inner conductor terminal 10, a part of the bending moment is received by the portion 71 adhered to a lateral surface of the protruding portion 46 and the portion 72 adhered to a lateral surface of the protruding portion 56 in the molded portion 70. As a result, an excessive stress is less likely to act on the solder (see
Further, in the above-described embodiment and embodiments illustrated in
The characteristics of the embodiments of the above inner conductor terminal 10 and the terminal unit 1 according to the present invention will be briefly summarized and listed in the following [1] to [4].
[1] An inner conductor terminal (10) comprising:
a connection terminal (40);
a crimping terminal (50);
a chip-type electronic element (60); and
a molded portion (70),
wherein the connection terminal (40) includes a connection portion (41) that is connected to a mating terminal at a tip end portion thereof,
wherein the crimping terminal (50) includes an inner conductor crimping portion (51) that crimps an inner conductor (81) of a coaxial cable (80) at a base end portion thereof,
wherein the chip-type electronic element (60) is mounted on a base end portion (42) of the connection terminal (40) and a tip end portion (52) of the crimping terminal (50) so as to couple the base end portion (42) of the connection terminal (40) with the tip end portion (52) of the crimping terminal (50),
wherein the molded portion (70) covers peripheries of the base end portion (42) of the connection terminal (40), the tip end portion (52) of the crimping terminal (50), and the chip-type electronic element (60),
wherein at least one of the base end portion (42) of the connection terminal (40) and the tip end portion (52) of the crimping terminal (50) includes a convex portion (45, 55) or a recessed portion (43, 44, 53, 54) on a surface thereof, and
wherein the molded portion (70) covers a periphery of the convex portion (45, 55) or enters the recessed portion (43, 44, 53, 54).
[2] The inner conductor terminal (10) according to the above-described [1],
wherein each of the base end portion (42) of the connection terminal (40) and the tip end portion (52) of the crimping terminal (50) has a flat-plate shape,
wherein the recessed portion includes a through hole (43, 53) penetrating in a plate thickness direction, and
wherein the inside of the through hole (43, 53) is filled with the molded portion (70).
[3] The inner conductor terminal (10) according to the above-described [2],
wherein the through hole (43, 53) includes a protruding portion (46, 56) extending from an inner wall surface of the through hole (43, 53) toward a radially inner side.
[4] A coaxial cable terminal unit (1) comprising:
the inner conductor terminal (10) according to any one of the above-described [1] to [3];
a dielectric (20); and
an outer conductor terminal (30),
wherein a terminal accommodation chamber (21) accommodating and retaining the inner conductor terminal (10) is formed through the dielectric (20), and
wherein the outer conductor terminal (30) includes a shell portion (31) internally provided with the dielectric (20) at a tip end portion thereof and an outer conductor crimping portion (32) crimping an outer conductor (83) of the coaxial cable (80) at a base end portion thereof.
1: terminal unit
10: inner conductor terminal
20: dielectric
21: terminal accommodation chamber
30: outer conductor terminal
31: shell portion
32: outer conductor crimping portion
40: connection terminal
41: connection portion
42: base end portion
43: through hole (recessed portion)
44: notch (recessed portion)
45: convex portion
46: protruding portion
50: crimping terminal
51: inner conductor crimping portion
52: tip end portion
53: through hole (recessed portion)
54: notch (recessed portion)
55: convex portion
56: protruding portion
60: chip-type electronic element
70: molded body (molded portion)
80: coaxial cable
81: inner conductor
83: outer conductor
Number | Date | Country | Kind |
---|---|---|---|
2018-113124 | Jun 2018 | JP | national |