Electrical PTC heater ensuring even dissipation has leaf spring - has rectangular cavity in carrier to accommodate heating element and contact plates

摘要

A PTC heater element comprises an aluminium profile with an electrically insulated heating element set between contact plates, with a pressure spring. The profile (1) has a rectangular cross-section cavity and the upper wall of this is deformed inwardly so as to press the element assembly (2, 3) together. On this wall, a leaf spring (5) is anchored into the profile and presses against the deformed-inward wall. Pref. the spring is held in longitudinal grooves. The upper wall of the cavity is pref. of reduced thickness compared with the other walls. ADVANTAGE - Constant output at both sides even after long operation.