Hydraulic crane hoist control lever velocity limiting device

摘要

An apparatus for controlling hoist control lever velocity on hydraulic cranes. The device is connected to the hoist control lever via a linkage. The device contains a housing which defines a fluid circuit. A slidably mounted pressurizing component communicates with the fluid circuit and is connected to the linkage. The fluid circuit contains a flow restricting device. When the hoist control lever is moved from a first position, wherein the hoist is stationary to a second position, wherein the hoist is moving, the linkage exerts an inward force on the pressurizing component moving the pressurizing component from a neutral to a pressurizing position. Such movement in turn induces a pressure build-up within the fluid circuit. Flow restricting device within the fluid circuit exerts a back pressure on the pressurizing component thereby through the actions of a the pressurizing component and the linkage limits the velocity of the hoist control lever. Biasing device acting on the pressurizing component provides an outward force to aid in return of the pressurizing component from a pressurizing position to a neutral position.