摘要 |
An exemplary elevator braking device comprises a brake housing. A plurality of rollers are supported by the brake housing. The rollers are arranged to be positioned on opposite sides of a guiderail. The rollers are selectively moveable between a first position in which the rollers are spaced apart a first distance and a second position in which the rollers are spaced apart a second, smaller distance so that the rollers engage and roll along opposite sides of the guiderail. At least one biasing member is supported by the brake housing. The biasing member is associated with at least one of the rollers and biases the associated roller toward the other roller in the second position. A plurality of braking surfaces are supported by the brake housing. At least one braking surface is associated with each of the rollers. Each braking surface engages a periphery of the associated roller that faces the side of the guiderail. Friction between the periphery of the associated roller and the braking surface provides a stopping force. |