Caster for shopping trolleys - is suitable for use on escalators and has brake formed by projection on hub of secondary roller meshing with teeth on main roller

摘要

The caster (1), esp. for shopping trolleys, has main (8) and secondary (31) rollers. The secondary roller, which fits in the longitudinal grooves of escalators, rotates on a vertically moving hub (20) and is held constantly against the floor by a spring. On escalators, rotation of the main roller is prevented by a projection (28) on the moving hub meshing with teeth (12a) on the main roller. The clearance between the projection and teeth, when meshing, is at least three deg. USE/ADVANTAGE - The brake can operate at higher roller speeds.