| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide electric equipment such as a blower and a ventilator capable of coping even with a small air volume variation in a process of air volume constant control, reducing an air volume variation even when a pressure loss temporarily changes, and capable of realizing the air volume constant control by shortening even convergence time. <P>SOLUTION: This blower is operated with the constant air volume by using a supply electric current to an inverter circuit and a rotating speed detected by a rotating speed detecting means, and comprises a low voltage DC voltage converting means 8 composed of a chopper circuit, an electric current detecting means 21 for detecting an electric current supplied to the inverter circuit 6, and a supply electric current value control means 22 for performing feedback control while varying voltage outputted from the low voltage DC voltage converting means 8 by controlling a low voltage DC voltage valve changing means 14 to control an average electric current value supplied to the inverter circuit 6 detected by the electric current detecting means 21 constant in an indicated electric current value, and provides a characteristic of reducing the air volume variation to a load change. <P>COPYRIGHT: (C)2007,JPO&INPIT |
