Safety device for an aerial lift
AssigneeBlue Sky Access Ltd.
InventorPaul Cummings
Life of this patent
Estimating the term…
Abstract
An aerial lift having a basket or cage having a control panel for an operator standing in the basket to maneuver the basket to a desired location, a safety switch means operable to prevent further movement of the basket in unsafe conditions, and a safety device comprising a load cell or strain gauge on the cage and an auxiliary safety switch operatively connected to the load cell via an amplifier is connected in series with the safety switch means, the auxiliary switch being operable to cut off power to the safety switch means when the sensed load on the cage exceeds a predetermined value, typically if the load strikes a stationary object.
Claims11
An aerial lift comprising:
- a basket or cage with controls which permit an operator standing in the basket or cage to maneuver the basket or cage to a desired location;
- a safety switch which needs to be closed before the controls become operable;
- and
- a safety device including a load cell or strain gauge and an auxiliary safety switch operatively connected to the load cell or strain gauge and connected in series with the safety switch, the auxiliary safety switch being operable to cut off power to the safety switch when a load value is sensed that exceeds a predetermined load value indicating a hitting event;
- wherein the basket or cage has a floor surrounded by a safety barrier, and the load cell or strain gauge of the safety device is fixed to a material storage rack, for use in supporting lengths of material, secured within the safety barrier and standing on the floor of the basket or cage;
- wherein a plurality of aligned cradles for use in supporting lengths of material are mounted on the material storage rack, and at least one load cell or strain gauge is operatively located between a respective cradle and the material storage rack;
- wherein each cradle has a downwardly extending tubular leg which is mounted on a spigot mounted on the material storage rack, and each of said load cells or strain gauges is located to sense loads acting between said tubular leg and said spigot of the respective cradle.
Dependencies are inferred from the claim text.