| 摘要 |
<p>A device for sensing an rpm of a lifting reel drum for a ceiling type air conditioner is provided to precisely sense a drum rpm of a lifting reel by first and second optical sensors and sensor holes, thereby precisely lowering a grill at a desired position. A device for sensing an rpm of a lifting reel drum for a ceiling type air conditioner includes a plurality of sensor holes(100) disposed at edge parts of one of right and left sides of a drum(70) by a uniform interval and rotating in the same direction with the drum. First and second optical sensors(200,210) are positioned at both sides of the sensor holes, and sense passing of the sensor holes to recognize an rpm of the drum, so that the first and second optical sensors transmit the drum rpm to a printed circuit board.</p> |
