Reflowable circuit protection device

摘要

A circuit protection device includes a substrate with first and second electrodes connected to the circuit to be protected. The circuit protection device also includes a heater element. A sensing element facilitates an electrical connection between the first and second electrodes. A flux material is provided around the sensing element. In a preferred embodiment, the flux contains a first component that is a polar material and a second component that is a non-polar material. A spring element exerts a force on the sensing element. The sensing element resists the force applied by the spring element. Upon detection of an activation, or fault, condition, the sensing element loses resilience and no longer resists the force exerted by the spring element, resulting in the spring element severing the electrical connection between the first and second electrodes. The flux allows the spring element to sever the electrical connection without dragging the sensing element.

主权项

1. A circuit protection device comprising:
a substrate comprising a first electrode and a second electrode; a sliding contact disposed on the substrate; a sensing element electrically coupled to the first electrode, the second electrode and the sliding contact; a flux disposed around the sensing element in the form of a film; and a spring element, wherein the spring element is disposed in an opening of the substrate and held in tension by the sliding contact; wherein the sensing element resists a force exerted on the sliding contact by the spring element on the sensing element until, upon detection of an activation condition, the sensing element loses resilience and the force exerted on the sliding contact by the spring element causes the spring element to sever the electrical connection.