JP2004335125A - Lead wire for connection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead wire for connection improvable in heat resistance, voltage withstanding characteristics, flexibility at a low temperature, mechanical strength and other characteristics through improvement of the structure of an insulating body and a sheath layer, suitable, for instance, for a lead wire of a discharge lamp such as a metal halide lamp as a light source for a vehicular lighting device. <P>SOLUTION: The lead wire for connection is constituted of an insulating electric wire with an insulating body made of a polymer material having heat resistance and voltage withstanding characteristics applied onto the outer periphery of a conductor, and a sheath layer made of a polymer material having heat resistance and mechanical strength applied onto the outer periphery of the insulating wire and it is characterised by having a voltage withstanding property of 10 kV of direct current voltage and a flexibility of 250 mm or less at minus 40°C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００３９】
本実施の形態によるリード線（実施の形態１乃至実施の形態４）は全ての評価項目に対して合格基準を満たしており、耐熱性、耐電圧特性、低温可とう性及び機械的強度をバランス良く兼ね備えている。比較例１は低温での可とう性が劣っている。
【００４０】
尚、本発明は上記の実施の形態に限定されるものではない。例えば、本発明の接続用リード線は、シース層の外周に導電性を有するスリーブを形成しても良い。こうすることにより、接続用リード線から発生するノイズを効果的に除去することができる。
【００４１】
【発明の効果】
以上詳述したように本発明によれば、絶縁体やシース層の構成を改良することにより耐熱性、耐電圧特性、低温時における可とう性、機械的強度などの特性を向上させることが可能な、例えば、車輌用灯具の光源であるメタルハライドランプ等の放電ランプのリード線として好適な接続用リード線を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態を示す図で、接続用リード線の概略断面図である。
【図２】耐電圧特性の評価状態を示す説明図である。
【図３】低温可とう性の評価状態を示す説明図である。
【符号の説明】
１ 接続用リード線
２ 導体
３ 絶縁体
４ 絶縁電線
５ シース層[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to, for example, a lead wire connected to a discharge lamp such as a metal halide lamp which is a light source of a vehicle lamp, and in particular, by improving the configuration of an insulator or a sheath layer, heat resistance, withstand voltage characteristics, and low temperature. The present invention relates to a device for improving characteristics such as flexibility at the time and mechanical strength.
[0002]
[Prior art]
Heat resistance that can withstand the high temperature (about 120 to 125 ° C.) of the discharge lamp is applied to a lead wire connected to a discharge lamp such as a metal halide lamp used as a light source of a vehicle lamp when the discharge lamp is turned on. Withstand voltage characteristics that can withstand a DC voltage of about 10 kV to 25 kV, flexibility from the viewpoint of workability of assembling a discharge lamp to a lamp, mechanical strength that does not damage even if it comes into contact with other components (scratch resistance ), Etc. are required.
[0003]
Conventionally, as a lead wire satisfying such characteristics, for example, there is a lead wire disclosed in Patent Document 1. The lead wire disclosed in Patent Document 1 has a rubber composition in which an inner coating layer and an outer coating layer sequentially formed on a conductor circumference both contain a tetrafluoroethylene-α-olefin copolymer as a main component. It was done.
[0004]
This connection lead wire has properties such as heat resistance, withstand voltage characteristics, assembly workability and mechanical strength.In addition, it does not generate harmful gases such as siloxane gas when exposed to high temperatures, Even if a high voltage is applied in the applied state, there is no problem such that a hole is formed in the insulator or the sheath layer.
[0005]
[Patent Document 1]
JP-A-9-204820
[Problems to be solved by the invention]
In recent years, among discharge lamps used in automobiles, among other vehicle lamps, a movable discharge lamp in which the discharge lamp itself can move up, down, left, and right in three dimensions has begun to be used from the viewpoint of improving safety.
[0007]
Therefore, for example, when the lead wire disclosed in Patent Document 1 is applied to this movable discharge lamp, the lead wire disclosed in Patent Document 1 becomes hard in a low-temperature atmosphere, and thus the discharge lamp is There is a risk that it will be difficult to move.
[0008]
The present invention has been made in order to solve such problems of the prior art, and an object of the present invention is to improve the structure of an insulator and a sheath layer to thereby improve heat resistance, withstand voltage characteristics, and low temperature. For example, it is an object of the present invention to provide a connection lead wire that can improve characteristics such as flexibility and mechanical strength and is suitable as a lead wire of a discharge lamp such as a metal halide lamp which is a light source of a vehicle lamp. .
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a connecting lead wire according to claim 1 of the present invention comprises: an insulated wire having a conductor covered with an insulator made of a polymer material having heat resistance and withstand voltage characteristics; A sheath layer made of a polymer material having heat resistance and mechanical strength coated on the connection lead wire, wherein the lead wire has a withstand voltage characteristic of a DC voltage of 10 kV or more. , -40 ° C. is 250 mm or less.
[0010]
Here, as the polymer material forming the insulator, a material having heat resistance and withstand voltage characteristics is used. For example, a silicone rubber mixture, a crosslinked polyethylene mixture, an ethylene-tetrafluoroethylene copolymer (ETFE), a tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA) And fluorine resins such as polytetrafluoroethylene (PTFE).
[0011]
As the polymer material constituting the sheath layer, a material having heat resistance and mechanical strength is used. For example, ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), polytetrafluoroethylene (PTFE) , A fluororesin such as polyvinylidene fluoride (PVDF), a composition containing a tetrafluoroethylene-α-olefin copolymer as a main component, a polyetheretherketone (PEEK), a polyphenylene sulfide (PPS), a polyimide, a polyurethane elastomer composition Products, polyester elastomer compositions and the like. In the present invention, various additives such as a cross-linking agent and a flame retardant may be appropriately compounded for the purpose of further improving heat resistance, voltage resistance, flame retardancy and the like with these polymer materials as main components. It is possible.
[0012]
Therefore, according to the first aspect of the present invention, since the insulator and the sheath layer are both formed of a heat-resistant polymer material, they deteriorate even when exposed to a high temperature of about 120 to 125 ° C. during actual use. There is no. In addition, since it has a withstand voltage characteristic of DC voltage of 10 kV or more, it is used in applications where a high voltage of DC voltage of about 10 kV to 25 kV is applied when the discharge lamp is turned on, for example, a metal halide lamp which is a light source of a vehicle lamp. And the like can be suitably used as a lead wire. In addition, since the flexibility at -40 ° C is 250 mm or less and has excellent low-temperature flexibility, it can be suitably used as a lead wire of a movable discharge lamp in which the discharge lamp itself can move three-dimensionally. can do. Further, since the sheath layer is formed of a polymer material having mechanical strength, the sheath layer is not damaged even if it comes into contact with other components.
[0013]
A connecting lead according to claim 2 of the present invention is the connecting lead according to claim 1, wherein the insulated wire has a flexibility at -40 ° C of 180 mm or less. is there.
[0014]
In the present invention, an insulated wire is designed by appropriately combining a conductor configuration and a constituent material of an insulator so as to satisfy flexibility at a low temperature. The constituent material of the conductor configuration and the insulator is not particularly limited as long as the above properties are satisfied. If the above characteristics are not satisfied, the low-temperature flexibility of the connection lead wire obtained by the present invention tends to decrease.
[0015]
Therefore, according to the second aspect of the present invention, the flexibility of the insulated wire at −40 ° C. is 180 mm or less, and the insulated wire has extremely low temperature flexibility, so that the discharge lamp itself can move three-dimensionally. It can be particularly preferably used as a lead wire of a movable discharge lamp.
[0016]
According to a third aspect of the present invention, there is provided a connecting lead according to the first or second aspect, wherein the insulator is made of a silicone rubber mixture.
[0017]
Therefore, according to the third aspect of the present invention, since the insulator is formed from the silicone rubber mixture and the insulated wire has extremely excellent low-temperature flexibility, the discharge lamp itself can move three-dimensionally. It can be particularly preferably used as a lead wire of a type discharge lamp.
[0018]
The connecting lead according to claim 4 of the present invention is the connecting lead according to claim 1, 2 or 3, wherein the sheath layer has a bending elastic modulus (MPa) × −40 ° C. It is characterized by being formed from a polymer material such that a numerical value represented by a cross-sectional area (mm ² ) becomes 4 × 10 ⁴ N or less.
[0019]
Here, as described above, as the polymer material constituting the sheath layer, for example, ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene -Perfluoroalkyl vinyl ether copolymer (PFA), fluororesin such as polytetrafluoroethylene (PTFE), composition containing tetrafluoroethylene-α-olefin copolymer as a main component, polyetheretherketone (PEEK) , Polyphenylene sulfide (PPS), polyimide, polyurethane elastomer composition, polyester elastomer composition and the like.
[0020]
In the present invention, a sheath layer is formed by coating the above polymer material on the outer periphery of the insulated wire. The thickness of the sheath layer is not particularly limited as long as it satisfies the above values (the value expressed by the flexural modulus (MPa) at −40 ° C. × cross-sectional area (mm ² ) is 4 × 10 ⁴ N or less). Not done. If the value exceeds the above value, the low-temperature flexibility of the connection lead wire obtained by the present invention tends to decrease.
[0021]
When forming the sheath layer, it is preferable to take measures for improving the adhesion between the insulator and the sheath layer. Examples of such measures include a conventionally known method such as a method using an adhesive and a method of performing a primer treatment. By taking such measures, it is possible to effectively prevent wrinkles from being generated on the sheath layer surface.
[0022]
Therefore, according to the invention of claim 4, the sheath layer is made of a polymer such that the numerical value represented by the flexural modulus (MPa) × cross-sectional area (mm ² ) at −40 ° C. becomes 4 × 10 ⁴ N or less. Since it is made of a material, properties such as heat resistance and mechanical strength can be further improved without impairing the excellent low-temperature flexibility of the insulated wire. In addition, when forming the sheath layer, various polymer materials can be selected in consideration of the intended use, cost performance, and the like, so that there is also an effect that product variations are widened.
[0023]
The connection lead wire according to claim 5 of the present invention is the connection lead wire according to claim 1 or claim 2 or claim 3 or claim 4, wherein the sheath layer is made of a polyurethane elastomer composition or a polyester elastomer. It is characterized by comprising a composition.
[0024]
Here, examples of the polyurethane elastomer composition include polyester urethane elastomers (adipate type, caprolactone type, polycarbonate type) and those containing a polyether type urethane elastomer as a main component. The system type is particularly preferable because of its excellent heat resistance.
[0025]
In addition, as the polyester elastomer composition, a copolymer type in which the hard segment is an aromatic polyester, the soft segment is an aliphatic polyether, and a copolymer type in which the hard segment is an aromatic polyester and the soft segment is an aliphatic polyester are commercially available. However, any of these may be used. Further, hard segments and soft segments having various polymerization ratios are known.
[0026]
Therefore, according to the fifth aspect of the present invention, since the sheath layer is formed from the polyurethane elastomer composition or the polyester elastomer composition, heat resistance and mechanical properties can be maintained without impairing the excellent low-temperature flexibility of the insulated wire. Properties such as strength can be further improved. Further, since the sheath layer can be formed to be thin, the cost performance is further improved.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In this embodiment, it is assumed that the present invention is applied to a connection lead wire of a discharge lamp such as a metal halide lamp which is a light source of a vehicle lamp.
[0028]
First embodiment A connection lead 1 according to a first embodiment of the present invention has a configuration as shown in FIG. First, there is a conductor 2 having a cross-sectional area of 0.5 mm ² (outer diameter 1.0 mm) obtained by assembling and twisting 21 tin-plated annealed copper wires (TA) having an element wire diameter of 0.18 mm. As the body 3, a silicone rubber mixture is extrusion-coated with a thickness of 1.25 mm to form an insulated wire 4 having an outer diameter of 3.5 mm. The silicone rubber mixture of the insulator 3 is crosslinked. Further, on the outer periphery of the insulated wire 4, a polycarbonate-based polyurethane elastomer composition (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: Rezamin P890) as the sheath layer 5 has a thickness of 0.15 mm and a flexural modulus at −40 ° C. (MPa) × cross-sectional area (mm ² ) = 1.8 × 10 ⁴ N]. The connection lead wire 1 has such a configuration, and its finish outer diameter is 3.8 mm.
[0029]
Second Embodiment According to a second embodiment of the present invention, the connecting lead wire 1 has a configuration as shown in FIG. First, there is a conductor 2 having a cross-sectional area of 0.5 mm ² (outer diameter 1.0 mm) obtained by assembling and twisting 21 tin-plated annealed copper wires (TA) having an element wire diameter of 0.18 mm. As a body 3, a silicone rubber mixture is extrusion-coated with a thickness of 0.5 mm to form an insulated wire 4 having an outer diameter of 2.0 mm. The silicone rubber mixture of the insulator 3 is crosslinked. Further, on the outer periphery of the insulated wire 4, a polycarbonate polyurethane elastomer composition (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: Rezamin P890) as the sheath layer 5 has a thickness of 0.3 mm and a flexural modulus at −40 ° C. (MPa) × cross-sectional area (mm ² ) = 2.2 × 10 ⁴ N]. The connection lead wire 1 has such a configuration, and its finish outer diameter is 2.6 mm.
[0030]
Third Embodiment A connection lead 1 according to a third embodiment of the present invention has a configuration as shown in FIG. First, there is a conductor 2 having a cross-sectional area of 0.5 mm ² (outer diameter 1.0 mm) obtained by assembling and twisting 21 tin-plated annealed copper wires (TA) having an element wire diameter of 0.18 mm. As the body 3, a silicone rubber mixture is extrusion-coated with a thickness of 1.25 mm to form an insulated wire 4 having an outer diameter of 3.5 mm. The silicone rubber mixture of the insulator 3 is crosslinked. A polyester elastomer composition (manufactured by Toyobo, trade name: Perprene S1002) as the sheath layer 5 is further provided on the outer periphery of the insulated wire 4 with a thickness of 0.15 mm [bending elastic modulus (MPa) at −40 ° C. × cross section). Area (mm ² ) = 1.0 × 10 ⁴ N]. The connection lead wire 1 has such a configuration, and its finish outer diameter is 3.8 mm.
[0031]
Fourth embodiment A connection lead 1 according to a fourth embodiment of the present invention has a configuration as shown in FIG. First, there is a conductor 2 having a cross-sectional area of 0.5 mm ² (outer diameter 1.0 mm) obtained by assembling and twisting 21 tin-plated annealed copper wires (TA) having an element wire diameter of 0.18 mm. As a body 3, a silicone rubber mixture is extrusion-coated with a thickness of 0.5 mm to form an insulated wire 4 having an outer diameter of 2.0 mm. The silicone rubber mixture of the insulator 3 is crosslinked. A polyester elastomer composition (manufactured by Toyobo, trade name: Perprene S1002) as the sheath layer 5 is further provided on the outer periphery of the insulated wire 4 with a thickness of 0.3 mm [bending elastic modulus (MPa) at −40 ° C.) × shear. Area (mm ² ) = 1.3 × 10 ⁴ N]. The connection lead wire 1 has such a configuration, and its finish outer diameter is 2.6 mm.
[0032]
Here, in order to evaluate the characteristics of a total of four types of lead wires obtained as described above, evaluation tests as shown below were performed on heat resistance, withstand voltage characteristics, low-temperature flexibility, and mechanical strength, respectively. went. The results are shown in Table 1. For comparison, a lead wire having the configuration disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 9-204820) was prepared as Comparative Example 1, and a similar evaluation test was performed.
[0033]
Comparative Example 1
First, there is a conductor 2 having a cross-sectional area of 0.5 mm ² (outer diameter 1.0 mm) obtained by assembling and twisting 21 tin-plated annealed copper wires (TA) having an element wire diameter of 0.18 mm. As a body 3, a rubber composition containing a tetrafluoroethylene-α-olefin copolymer as a main component is extrusion-coated with a thickness of 0.9 mm to form an insulated wire 4 having an outer diameter of 2.8 mm. Note that the insulator 3 is crosslinked. The outer periphery of the insulated wire 4 is further extrusion-coated with a 0.6 mm-thick rubber composition containing a tetrafluoroethylene-α-olefin copolymer as a main component as a sheath layer 5. The finish outer diameter of the lead wire 1 is 4.0 mm.
[0034]
The evaluation method is as follows.
Heat resistance Each sample was left in a high-temperature bath maintained at 125 ° C. for 14 days, taken out, and wound around a mandrel having a diameter of 3.8 mm six times to check for cracks. Those having no cracks were judged as acceptable.
[0035]
First, the sheath layer and the insulator of about 25 mm at both ends of the sample cut to a length of 1050 mm are peeled off, and the conductors are twisted with each other. Then, the portion of the insulator and the sheath layer of the sample is immersed in water. Let it. Next, a DC voltage is applied between the conductor and the ground to increase the voltage to 10 kV and 25 kV at a speed of 500 v / sec, and then the state is maintained for 30 minutes. Those that survived were considered acceptable. FIG. 2 is an explanatory diagram illustrating an evaluation state of the withstand voltage characteristics.
[0036]
Low temperature flexibility First, after stripping off about 25 mm of the sheath layer and the insulator at both ends of the sample cut to a length of 1050 mm, mark the center of the sample, and furthermore mark lines at 250 mm each on the left and right from the center point pull. Next, after tying the conductors at both ends, the sample is left for 1 hour in a low-temperature bath maintained at -40 ° C. Then, this sample was hooked on a mandrel having a diameter of 13 mm placed in a low-temperature tank so that the center point thereof came, and a load of 20 g was applied to the lower end, and the distance between the marked lines after 1 minute was measured. Those having this distance of 250 mm or less were accepted. Table 1 also shows numerical values obtained when the same evaluation was performed at normal temperature (25 ° C.). FIG. 3 is an explanatory diagram showing an evaluation state of low-temperature flexibility.
[0037]
Mechanical strength (scratch resistance)
The evaluation of the scratch resistance was performed according to the cut-through test CSA C22.2 No. 03 (1996 version). Those having a dielectric breakdown strength of 78.4 N or more were accepted.
[0038]
[Table 1]

[0039]
The lead wire according to the present embodiment (Embodiments 1 to 4) satisfies the acceptance criteria for all evaluation items, and balances heat resistance, withstand voltage characteristics, low-temperature flexibility, and mechanical strength. Well combined. Comparative Example 1 is inferior in flexibility at low temperatures.
[0040]
Note that the present invention is not limited to the above embodiment. For example, in the connection lead wire of the present invention, a conductive sleeve may be formed on the outer periphery of the sheath layer. This makes it possible to effectively remove noise generated from the connection lead wire.
[0041]
【The invention's effect】
As described in detail above, according to the present invention, it is possible to improve characteristics such as heat resistance, withstand voltage characteristics, flexibility at low temperature, and mechanical strength by improving the configuration of the insulator and the sheath layer. For example, it is possible to provide a connection lead wire suitable as a lead wire of a discharge lamp such as a metal halide lamp which is a light source of a vehicle lamp.
[Brief description of the drawings]
FIG. 1 is a view showing an embodiment of the present invention and is a schematic sectional view of a connecting lead wire.
FIG. 2 is an explanatory diagram showing an evaluation state of withstand voltage characteristics.
FIG. 3 is an explanatory diagram showing an evaluation state of low-temperature flexibility.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Connection lead wire 2 Conductor 3 Insulator 4 Insulated wire 5 Sheath layer

Claims (5)

An insulated wire in which an insulator made of a polymer material having heat resistance and withstand voltage characteristics is coated on the outer periphery of the conductor, and a sheath layer made of a polymer material having heat resistance and mechanical strength coated on the outer periphery of the insulated wire Wherein the lead wire has a withstand voltage characteristic of a DC voltage of 10 kV or more, and has a flexibility at -40 ° C. of 250 mm or less. Lead wire. The connection lead according to claim 1, wherein the insulated wire has a flexibility at -40C of 180 mm or less. 3. The connection lead according to claim 1, wherein the insulator is made of a silicone rubber mixture. 4. The connection lead according to claim 1, 2, or 3, wherein the sheath layer has a numerical value expressed by a flexural modulus at 40 ° C. (MPa) × a cross-sectional area (mm ² ) of 4 × 10. A connection lead wire formed of a polymer material so as to be ⁴ N or less. 5. The connection lead according to claim 1, wherein the sheath layer is made of a polyurethane elastomer composition or a polyester elastomer composition.

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