Patent attributes
A hoist system for handling a 400 Hz cable used for aircraft electrical servicing, that utilizes electrical circuitry where wire rope position sensing is accomplished using a grounding circuitry. The system employs an AC drive that relies on circuit completion through “sinking logic.” Electrically connected are wire rope guide rollers, a control pendant, a bridge horizontal control relay, which is in electrical communication with a horizontal bridge lock-out bar. The wire rope is used as an electrical conductor for control voltage only. A lower limit contact bar extends above a plane between the wire rope guide rollers and the take-up spool, as serves to prevent the wire rope from rewinding in a reverse manner on the take-up spool. A horizontal bridge lock-out bar extends above a plane between the wire rope guide rollers and the take-up spool and is used to allow or inhibit horizontal bridge movement.
