| 摘要 |
<p>The element in a roller shutter has an elongated rectangular-sectioned hollow body, with elongated hook-sectioned extension on one side, and open cavity with slit on the other side for hook engagement. The cavity contains a U-sectioned modulating unit, and the slit is bounded by an elongated, inward-protruding lug acting together with the hooked piece. This lug (8) is hook-shaped in cross-section, with the modulating unit (2) led round it inside and outside. A trough (14) for engagement by the end (18) of the extension is formed in the modulating unit, near the lug. At an interval from its end the extension has an arc-shaped piece (17) with radius matching the interval. Noise attenuation is improved during any movement between linked shutter elements.</p> |
