Apparatus for controlling cargo handling position
AssigneeToyo Unpanki Co., Ltd.
InventorNobuo Masano
Life of this patent
Estimating the term…
Abstract
An apparatus for controlling the angular position of the booms of an earthwork vehicle such as a wheeled tractor loader includes a shock absorber, by which the hydraulic pressure to be applied to a cargo handling valve for changing the position of a valve spool therein is lowered so as to lessen the shocks which are felt when the booms come to a stop position.
Claims1
An apparatus for controlling cargo handling position, comprising a cargo handling valve for controlling a cargo handling device such as a hydraulic cylinder, a control valve connected to said cargo handling valve through a fluid pressure circuit adapted to provide said cargo handling valve with hydraulic pressure for changing the position of a valve spool therein, a retainer for holding said control valve in a position adapted to spontaneously let fall a boom, another retainer for holding said control valve in a position adapted to hold said boom in an uppermost position, a position sensor for detecting the rise and fall of said cargo handling device, a presetting unit for presetting the uppermost and lowermost stop positions of said cargo handling device, a shock absorber for reducing the hydraulic pressure applied through the fluid pressure circuit, and a controller for controlling said retainers and said shock absorber on the basis of signals taken from said position sensor and said presetting unit, said controller having a function of storing the signals taken from said presetting unit, a function of comparatively evaluating the signals taken from said presetting unit and those taken from said position sensor, a function of controlling said shock absorber by feeding a control signal thereto for effecting a hydraulic pressure drop on the basis of the result of said comparative evaluation, and a function of controlling said retainers by feeding signals thereto for releasing said retainers when said shock absorber has been fed with said control signal.
Dependencies are inferred from the claim text.