Elevator structure and brake system therefor

A method for operating a movable apparatus along a structure that defines a vertical pathway, and for stopping the movable apparatus along the pathway, the movable apparatus supported for movement along the vertical pathway, comprising the steps of:

• (a) providing a brake rail secured to the structure along the vertical pathway, the brake rail having along one edge thereof a multiplicity of regularly spaced teeth that define gaps between successive teeth;
• (b) providing a brake device secured to the movable apparatus, the brake device including a rotor having an outer cylindrical surface and a central axis of rotation, and including a helical thread on the outer cylindrical surface for loosely engaging the gaps in the brake rail,
• (c) providing an apparatus drive mechanism for powering the vertical movement of the movable apparatus;
• (d) moving under power the movable apparatus along the pathway;
• (e) rotating the rotor so that the thread loosely engages successive gaps in the brake rail and out of contact with the teeth of the brake rail during movement of the moveable apparatus;
• (f) moving the movable apparatus under power of the apparatus drive mechanism along the pathway to, and stopping and hovering under power at, a stop position, at which the rotor is rotationally stationary;
• and
• (g) rotating the thread of the rotor, with the moveable apparatus in the stop position, into contact and engagement with a top landing surface of a tooth on the brake rail.