US 4,453,672 A · Vehicle mounted aerial lift

Abstract

A lower boom is pivotally mounted on a turntable and moved upwardly and downwardly by a hydraulic cylinder, the lower end of which may be pivoted on the same pivot shaft as that on which a pair of links are pivoted. The outer ends of the links are pivotally connected to the lower end of a knee joint, preferably formed of heavy plate and attached to the inner end of an upper boom, while the outer end of the lower boom is pivotally attached to the knee joint above the links. An extensible boom, hydraulically moved inwardly and outwardly of the upper boom, may carry a workman's basket and/or a hydraulic nozzle, as for extinguishing fires. The distance between the pivotal connections of the links and the lower boom to the turntable, the relative length of the lower boom and links and the distance between the pivotal connections of the outer ends of the lower boom and the links to the knee joint or upper boom are preferably proportioned so that the outer end of the extensible boom, at any set position, will rise in a generally vertical line, as the lower boom is elevated. During such movement, the knee joint will remain on the opposite side of the center line of the turntable from the extensible boom and basket, thereby contributing materially to the balance of the structure and thereby, in many installations, avoiding the use of jack legs or outriggers. A special line for supplying water to the nozzle consists of pipes attached to the upper and lower boom, an extensible pipe within the upper boom pipe, hose connections between the pipes and between the lower end of the lower boom pipe and a supply pipe. The latter includes special fittings permitting the turntable to move through 360.degree. or more.

Claims18

Dependent claims

An aerial lift for a vehicle, comprising:

a support pivotally mounted on said vehicle for movement about an upright axis;
a lower boom whose inner end is pivotally connected to said support and extending generally horizontally in a storage position;
means for moving said lower boom upwardly and downwardly about the pivotal connection thereof and disposed at an acute angle to said lower boom in said storage position, said moving means being pivotally connected to said support and to said lower boom;
an upper boom whose inner end is pivotally associated with the outer end of said lower boom and which extends in a generally horizontal storage position above said lower boom;
link means whose inner end is pivotally connected to said support and whose outer end is pivotally associated with the inner end of said upper boom;
and
the relationship of the lengths between pivots of said lower boom and said link means, the distance between the pivotal connections of said lower boom and said link means to said support and the distances between the points of pivotal association between said lower boom and said link means with said upper boom being such that the outer end of said upper boom will be raised generally vertically as said lower boom is raised.

4 more elements

An aerial lift for a vehicle, comprising:

a pivotal support mountable on said vehicle;
a lower boom whose inner end is pivotally connected to said support;
means for moving said lower boom upwardly and downwardly about the pivotal connection thereof and pivotally connected between said support and said lower boom;
link means pivotally connected at the inner end thereof to said support and disposed on opposite sides of said moving means;
an upper boom whose inner end is pivotally associated with the outer end of said lower boom and said link means;
an extensible boom movable outwardly and inwardly from the upper end of said upper boom;
means for moving said extensible boom relative to said upper boom;
a device for accomplishing an objective connected to the outer end of said extensible boom;
and
joint means attached to the inner end of said upper boom, pivotally connected to the outer end of said lower boom at a position below said upper boom and pivotally connected to the outer end of said link means at a position below said pivotal connection to said lower boom, said joint means being formed of relatively heavy material to assist in counterbalancing the weight of said extensible boom and said device for accomplishing an objective.

7 more elements

Dependencies are inferred from the claim text.

Vehicle mounted aerial lift

Life of this patent

Vehicle mounted aerial lift

Life of this patent

Abstract

Claims18