| 摘要 |
<p>1. A method for automatically slowing down and stopping the slewing, change of reach and, optionally, the hoisting action, of machinery used on building sites, such as cranes, not provided with auxiliary slowing mechanisms, the method including measurement of the angle of orientation, of the length of travel of the truck, and, optionally, of the height of the hoist, and also including comparison of the measured values with predetermined values which depend on the limits of forbidden zones over which the load must not be carried, or dangerous zones, this measurement and comparison serving to determine the moment at which the movement of the machinery must be slowed down before being stopped altogether, should this prove necessary, characterised in that the angular speed (V) of slewing of the machinery is measured and that the value of this measurement is used in order to determine the force of the braking action, brought about by counter-slewing, a signal controlling the slowing down being sent to a relay acting upon the motor or motors of the machinery, either to bring it to a stop before it reaches the limit of the forbidden zone over which the load or the jib must not be carried, or to impose a speed reduction when crossing a dangerous zone.</p> |
