Miniature inductor with molded cover

摘要

A miniature variable inductor comprises a coil soldered to a pair of connecting skids. These skids are clipped to two oppositely disposed lateral walls of an injection-moulded plastics cover in the shape of a hollow die. A solid part of the cover and a hollow space lie between these two walls. A central opening through these walls, the solid part of the cover and the hollow space defines a housing for a movable ferromagnetic core. There is a screwthread on at least part of this core. The coil is disposed in the aforementioned hollow space coaxially with the central opening, encapsulated in resin. The central opening has a threaded portion where it passes through the solid part of the cover. This threaded portion is complementary to the thread on the core.