| 摘要 |
A braking apparatus is provided for braking the rotating part of a hoisting machine. The braking apparatus includes one or more brakes, which contain altogether at least one movable brake shoe, spring elements for activating the brake by moving the brake shoe forward, at least two electromagnets, which, when magnetized by a magnetizing current, apply a force of attraction to bodies conducting magnetic flux. The electromagnets are fitted to release the brake by pulling the brake shoe backwards by resisting the spring elements. The brake is fitted to be activated by reducing the magnetizing current of the electromagnet. The braking apparatus includes a power supply circuit for the electromagnets, which contains controllable power supply interrupting devices. The electromagnets are connected to the power supply circuit in such a way that the supply of magnetizing current to each electromagnet can be interrupted by means of at least two different interrupting devices. |
