Shielded wire and wire harness
A shielded wire includes an electrical wire including a conductor portion and a covering portion, a shield braid in which electrically conductive wire members are braided, and which covers an outer circumference of the electrical wire, a tubular sheath disposed on an outer circumference of the shield braid and made of an insulating resin.
1. A shielded wire comprising:
an electrical wire including a conductor portion and a covering portion;
a shield braid in which electrically conductive wire members are braided, and which covers an outer circumference of the electrical wire; and
a tubular sheath disposed on an outer circumference of the shield braid and made of an insulating resin,
wherein D1 is an inner diameter of the sheath in a state where the sheath is disposed on the outer circumference of the shield braid,
wherein t is a thickness of the sheath in the state where the sheath is disposed on the outer circumference of the shield braid,
wherein E is a modulus of elasticity of the sheath,
wherein μ A is a coefficient of static friction between the shield braid and the electrical wire,
wherein μ B is a coefficient of static friction between the shield braid and the sheath,
wherein F max is a value of a load which, in a fatigue test where a load is repeatedly applied to the shield braid in an axial direction of the braid, is obtained when an electrical resistance value of the shield braid is increased by 10% with respect to an initial value at a timing when the load is repeatedly applied 5 million times,
wherein D2 is an inner diameter of the sheath in a free state, and
wherein D2 satisfies following relational expression (1)
D
1
-
D
1
2
F
max
×
10
4
π
tE
(
μ
A
+
μ
B
)
≦
D
2
<
D
1.
(
1
)
2. A wire harness comprising the shielded wire according to claim 1 .