Vehicle mounted aerial lift

Claim 1

An aerial boom system for a fire-fighting vehicle comprising: an elongated boom mounted on the vehicle; power means for selectively raising and lowering the boom to a desired elevation; a conduit on the vehicle for carrying a flowable fire-retardant material to the outer end of the boom; an elongated hollow piercing nozzle coupled to the conduit and having a tapered point with at least one orifice therein for expelling the fire-retardant material; mounting means on the outer end of the boom for supporting the hollow piercing nozzle; drive means coupled to the mounting means for independently moving the hollow piercing nozzle in both a horizontal and a vertical plane; the hollow piercing nozzle extending beyond the end of the boom such that the hollow piercing nozzle can be used to penetrate a wall of a structure from a remote distance and enable a fire-retardant to exit the at least one orifice into the interior of the structure; and a slip clutch mounted between the outer end of the boom and the drive means such that undesirable forces on the elongated nozzle that may occur when piercing a structure are limited to a predetermined value in the Y plane perpendicular to the piercing direction of the elongated nozzle so as to protect the piercing nozzle, mounting, and drive means from damage.