| 摘要 |
PURPOSE:To enable the contact pressure of a heat responsive element to be easily controlled by installing the fixed piece and the bimetal piece of the heat responsive element, at least one of which is movable through an adjusting plate, on a base plate made of a heat-resisting insulator. CONSTITUTION:Usually, first of all, auxiliary discharge is set up between a main electrode 2a and an auxiliary electrode 6 through the first bimetal 17 and the second bimetal 18. Next, simultaneously with the operation of the first bimetal 17, main discharge between main electrodes 2a and 2b substitutes for the former auxiliary discharge to light a lamp. Here, if the movable contact and the fixed contact of the first bimetal 17 are fused as a result of certain causes, the operation of the second bimetal 18 initiates discharge between lead wires, which leads to the fusing of the lead wires to stop current and protect a ballast from damages. Besides, the fixed pieces and the bimetal pieces of the bimetals 17 and 18 are movable on the surface of a base plate 26 through an adjusting plate, and thus they can be finely adjusted. |
