Circuit board, electronic device having the circuit board and method of manufacturing the electronic device
A circuit board includes a substrate having opposite upper and lower surfaces, and an insertion hole extending through the upper and lower surfaces and having an expansion hole portion and an insertion hole portion connected to and communicating with each other. The insertion hole has a maximum width measured from one end of the insertion hole portion passing radially through the centers of the insertion hole portion and the expansion hole portion to one end of the expansion hole portion that is radially opposite to the one end of the insertion hole portion. The maximum width is greater than a hole diameter of the insertion hole portion, while the hole diameter of the insertion hole portion is greater than a hole diameter of the expansion hole portion. An electronic device having the circuit board and a method of manufacturing the same are also disclosed.
1 . An electronic device, comprising:
a circuit board including
a substrate having an upper surface and a lower surface opposite to each other, and an insertion hole extending through said upper surface and said lower surface, said substrate including a base layer and two copper foil layers respectively covering upper and lower sides of said base layer and respectively serving as said upper surface and said lower surface of said substrate, said insertion hole having an expansion hole portion and an insertion hole portion connected to and communicating with each other, said insertion hole having a maximum width measured from one end of said insertion hole portion passing radially through the center of said insertion hole portion and the center of said expansion hole portion to one end of said expansion hole portion that is radially opposite to said one end of said insertion hole portion, said maximum width being greater than a hole diameter of said insertion hole portion, said hole diameter of said insertion hole portion being greater than a hole diameter of said expansion hole portion, and
a conductive layer disposed in said insertion hole and electrically connected to said copper foil layers; and
an insert member inserted into said insertion hole of said circuit board and including an axially extending terminal post, at least two protruding arms extending radially and outwardly from two diametrically opposed sides of said axially extending terminal post and resting on said upper surface of said substrate, and at least two protruding legs that extend upwardly and inclinedly from said two diametrically opposed sides of said axially extending terminal post, that are spaced apart from and located below said protruding arms and that abut against said lower surface of said substrate, a maximum distance measured from a free end of one of said at least two protruding legs to a free end of the other one of said at least two protruding legs being smaller than said maximum width of said insertion hole but greater than said hole diameter of said insertion hole portion.
2 . The electronic device as claimed in claim 1 , further comprising a solder body soldered between said insert member and said conductive layer of said circuit board.
3 . The electronic device as claimed in claim 2 , wherein said conductive layer has a cylindrical portion electroplated on a wall surface of said substrate that defines said insertion hole, and two annular portions that extend outwardly, radially and respectively from upper and lower ends of said cylindrical portion, that respectively surround upper and lower ends of said insertion hole and that are respectively electroplated on said copper foil layers, said solder body being soldered between said protruding arms and an upper one of said annular portions of said conductive layer, between said axially extending terminal post and said cylindrical portion of said conductive layer, and between said protruding legs and a lower one of said annular portions of said conductive layer.