| 摘要 |
<p>A fabric press comprises a press with a heating element (11) a temperature sensor (17), and a microprocessor based controller programmed to apply electrical power initially to the element for a boost period during which the press temperature is limited to a boost temperature, and then at the end of the boost period, to reduce the applied power and thereafter to control the power to maintain the press temperature substantially at a lower normal temperature. The controller comprises microprocessor (14) which supplies trigger signals to a triac (12), the signals being timed to be applied at the zeros of the a.c. supply voltage and to switch the heater power for complete cycles of the supply voltage.</p> |
