| 摘要 |
<p>The mobile shutter (5) overlaps an armour plated fixed shutter, so that, when it moves up to the top, it completely closes off the counter position. The shutter slides in the strong frame risers (3), is guided by rollers, (9) and lodges in the top frame traverse (11). The hydraulic jack (5) is placed behind the counter position. It has a smooth continuous action, can be operated by push button or foot pedal, and can work as a result of sudden load noises such as breaking glass or the sound of a security alarm.</p> |
