THERMAL ACTUATOR

摘要

A known thermal actuator includes a capsule (1), which contains a diaphragm (4) controlling the position of a stem (7). A thermal expansion substance like wax (5) is contained in the capsule which operates as a thermostat in a thermostatically controlled valve such as a thermostatically controlled mixing valve. The stem (7) of the actuator is connected with a valve body movable between two valve seats for hot and cold medium, respectively, and the capsule is placed in the area of the mixed medium for transmitting the heat of the mixed medium to the thermal expansion substance. In order to present a simple and more effective actuator that can react promptly at changes of temperature and which does not require an extra temperature sensor, the capsule consists of an oblong cup-like sensor body (1), the surface of which is at least partly deformed (8, 9; 13; 14) in such a way that its thermal transmittance area is increased.