A powered jib boom attachment usable with mobile cranes, boom truck cranes, and telescopic boom assemblies having a telescopic crane boom with a distal tip, said jib boom attachment comprising:
- a jib boom mounting bracket having a lower portion and fixed connection to the distal tip of a telescopic crane boom;
- a jib boom rotation base in pivoting connection with said jib boom mounting bracket, allowing up and down vertical articulation of said jib boom rotation base relative to said jib boom mounting bracket, said jib boom rotation base having a bottom portion and a top surface positionable into a horizontal plane;
- a rotation bearing drive assembly having an upper portion rotatable up to approximately 360-degrees relative to a lower portion, said lower portion having fixed connection with said top surface of said jib boom rotation base, said rotation bearing drive assembly fully operational to provide approximately 360-degrees of rotation regardless of the boom angle of an attached telescopic crane boom, said jib boom mounting bracket staying in fixed in orientation to the connected telescopic crane boom distal tip during all rotation of said rotation bearing drive assembly and while transferring bending and torsion loads from said jib boom member to the connected telescopic crane boom;
- a jib boom support structure having fixed connection to said upper portion of said rotation bearing drive assembly, said jib boom support structure having a surface remote from said rotation bearing drive assembly in a geometric plane substantially parallel to that of said top surface of said jib boom rotation base, wherein when said top surface of said jib boom rotation base is in a horizontally-extending plane said surface of said jib boom support structure remote from said rotation bearing drive assembly is also in a horizontally-extending plane;
- a jib boom member having an upper surface and fixed connection to said jib boom support structure that places said upper surface of said jib boom member in the same geometric plane of said surface of said jib boom support structure remote from said rotation bearing drive assembly;
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- a linear leveling actuator connected between said lower portion of said jib boom mounting bracket and said bottom portion of said jib boom rotation base, said connection of said linear leveling actuator to said jib boom mounting bracket below said pivoting connection of said jib boom rotation base to said jib boom mounting bracket, said linear leveling actuator having a cylinder articulating said bottom portion of said jib boom rotation base up and down in response to out-of-level orientations of said top surface of said jib boom rotation base resulting from out-of-level orientations in said upper surface of said jib boom member, said linear leveling actuator automatically extending and contracting different amounts in response to each instance of out-of-level positioning experienced by said jib boom member, with said extension and contraction being proportional to the amount of out-of-level positioning said jib boom member attains and also being commenced as often as needed to maintain said top surface of said jib boom rotation base in a horizontally-extending plane, said linear leveling actuator also extending and contracting while a telescopic crane boom having fixed connection to said jib boom mounting bracket is raised and lowered;
- an electronic leveling sensor in fixed association with said jib boom rotation base and also in electrical communication with said linear leveling actuator;
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- power supply means adapted for providing power to operate said electronic leveling sensor and said linear leveling actuator, said power supply means associated with said jib boom rotation base and in electrical communication with said electronic leveling sensor and said linear leveling actuator, wherein when a change in load placed upon said jib boom member causes out-of-level positioning in said jib boom member and also in said jib boom support structure having fixed connection to said jib boom member, said top surface of said jib boom rotation base in a geometric plane substantially parallel to that of said jib boom support structure deviates from its horizontal plane, said electronic leveling sensor in fixed association with said jib boom rotation base senses said deviation and electrically communicates with said linear leveling actuator, causing said linear leveling actuator to automatically extend and contract a proportional amount in response and push or pull said jib boom rotation base an appropriate amount to cause said top surface of said jib boom rotation base, said jib boom support structure, and said jib boom member to regain level orientation in a horizontally-extending plane, with said automatic extension and contraction of said linear leveling actuator in response to out-of-level positioning in said jib boom member further occurring during articulation of the telescopic crane boom to which said jib boom mounting bracket has a fixed connection.