Boom articulating mechanism for aerial devices
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jul 29, 1986
Grant Date -
N/A
app pub date -
Nov 16, 1984
filing date -
Nov 16, 1984
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
In a truck mounted overcenter aerial device having an articulating boom assembly, a mechanism for articulating the upper boom relative to the lower boom. A star wheel on the upper boom is acted upon by a pair of linkages powered by hydraulic cylinders mounted on the lower boom. The linkages are pinned at their outer ends to the star wheel so that the upper boom is pivoted in opposite directions when the cylinders are extended and retracted. Each linkage includes pivotally connected links which fold up on the star wheel against stop surfaces as the linkage is extended. The stop surfaces are arranged to control the angular speed of the upper boom and the torque applied to it by the linkages as desired during each angular segment of articulation. The hydraulic control circuit for the cylinders includes counterbalance holding valves which maintain both linkages under tension at all times to avoid any slack or jerkiness when the boom goes overcenter.
First Claim
Other Claims data not available