초록 ▼

An electromagnetic sensor formed by integral resin molding of a sensing device in which a pointed protrusion and an apertured protrusion for positioning capable of complementally engagement to each other are provided one at an axial end face of the sensing device and the other at an inner surface of

An electromagnetic sensor formed by integral resin molding of a sensing device in which a pointed protrusion and an apertured protrusion for positioning capable of complementally engagement to each other are provided one at an axial end face of the sensing device and the other at an inner surface of a molding die. A plurality of circumferentially spaced apart axially extending portions in an intimate contact with an inner circumference of the molding die are provided to the outer circumference at a lower portion of a bobbin of the sensing device. The positioning protrusion on an axial end face of the sensing device is shaped such that the size in a direction perpendicular to a streamline of the resin is gradually decreased as it is away from a resin injection gate. The sensing portion is positioned stably in the molding die, resin molding can be applied as far as the top end of the pole piece to provide protection, and water proofness of the sensor is improved by intact contact with the resin.

대표청구항 ▼

[ What is claimed is:] [1.] An electromagnetic sensor formed by inserting a sensing device into a molding die and injecting a molten resin, thereby covering a periphery of the sensing device with the resin, said sensing device comprising a bobbin defining an axis and a radial direction, coils wound

[ What is claimed is:] [1.] An electromagnetic sensor formed by inserting a sensing device into a molding die and injecting a molten resin, thereby covering a periphery of the sensing device with the resin, said sensing device comprising a bobbin defining an axis and a radial direction, coils wound around the bobbin and a pole piece which is inserted through the bobbin along said axis and in which a lower portion of the pole piece is formed into a top end adapted to conform to a shape of a pulsar gear, said bobbin comprising:a plurality of axially extending portions disposed at a lower circumference of said bobbin, said axially extending portions being circumferentially spaced apart from each other and protruded radially so as to be substantially in an intimate contact with an inner circumferential wall of a recess formed contiguous with a bottom surface of a bobbin receiving portion of a molding die, thereby defining an axial gap between each of the adjacent extending portions for allowing the molten resin to flow around a second periphery of the top end; wherein the bobbin has a lower radial flange for engagement with a plurality of protrusions axially protruding from a bottom surface of the bobbin receiving portion of the molding die.