| 摘要 |
<p>A thermal switch reduces the power loss and heat generated in a current limit resistor after limiting inrush current, can self-hold a non-return state even when the temperature of the current limit resistor drops, and quickly returns when a power switch is turned off. A movable plate (8) is divided by an elongate opening (23) into a narrow width portion (21) and a wide width portion (22). The narrow width portion (21) is heated by conduction current split through a first terminal (3) and a second terminal (4), which are used for short-circuiting both ends of the current limit resistor when the movable plate (8) operates as the thermal switch (10) so as to close a contact point. The narrow width portion (21) thereby keeps a bimetal (9) warm by a small amount of localized heat to self-hold a non-return state and rapidly cools down the current limit resistor. When the power switch is turned off, heat generated in the narrow width portion (21) is rapidly cooled down, so that the thermal switch (10) returns quickly. This allows the current limit resistor to effectively function even when the power is turned on again at an early stage.</p> |
