US Patent 9676602 Aerial lift with safety device

A safety device for an aerial lift (10) having operator controls (23) for maneuvering its basket (20) to a desired location and including at least one passive normally closed safety switch (30)(130), e.g. an emergency switch, operable to cut electrical supply and prevent further movement of the basket (20), the safety device comprising a switch activation device (27,160,170) extending across the basket proximate to the controls (23) and an auxiliary safety switch (26) connected in series with the safety switch (30,130) with its contacts C1 normally closed (switch on) unless caused to open (switch off) by operation of the switch activation, thereby cutting off the electrical supply.