| 摘要 |
<p>The protective screen includes vertical blind slats which are suspended from a horizontal rail over the counter dividing staff from customers. Within a casing over the counter there is also a movable screen (1) which is normally held up away from the counter. The screen is held up by remotely controlled locking elements (2). In the event of an alarm, the movable screen may be released so that it slides down shutting off the counter. Its weight is sufficient to rotate the blind supports so that the blinds are closed. The rate at which the screen descends is controlled by pneumatic braking cylinders (6). These are adjusted to control the rate at which the air escapes from the cylinder, regulating the speed of descent.</p> |
