Patent ID: 7624967

Claim:
An opposed-rope driven telescoping mast assembly comprising: a stationary support; a longitudinal mast comprising a longitudinal section joined to move relative to the stationary support; a drive assembly having a weight that counterbalances at least a portion of the weight of the longitudinal section, the drive assembly comprising: a frame pivotally joined to the stationary support; a rotatable drum assembly mounted to the frame; and a first rope and a second rope, the first rope being joined to the drum assembly and to the longitudinal mast to pull the longitudinal section in a first direction, the second rope joined to the drum assembly and to the longitudinal mast to pull the longitudinal section in a second direction; a sensor operably coupled to the drive assembly to sense overload tension in the first rope or the second rope by movement of the drive assembly; and a spring joined to the drive assembly to support at least a portion of the weight of the longitudinal section.