| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce air cutting sound by securing the limit of deflection of a spiral wire member due to a pushing force from the front surface of a fan guard so as to be lower than a given value and reduce the number of radial wire members for the fan guard. SOLUTION: The pitch of a spiral wire member 7a for a fan guard 5a is set so as to be wide near the center of the fan guard 5a and so as to be narrow near the outer periphery of the fan guard 5 whereby the limit of deflection of the spiral wire member 7a due to a pushing force from the front surface of the fan guard can be secured so as to be lower than a given value while the number of radial wire members can be reduced whereby air cutting sound or hissing sound of a fan can be lowered.</p> |
