Patent ID: 8322797
Filing Date: 2012-12-04
Classification: B60T,F16D

Abstract:
1. A hydraulic device for actuating the braking of work vehicles, comprising: at least one delivery duct, which can be connected to a pressurized branch of a hydraulic circuit whereby said pressurized branch includes an accumulator; at least one discharge duct, which can be connected to a discharge and recovery branch of the hydraulic circuit; at least one feed duct for feeding a hydraulic actuator of a braking system released by elastic means; at least one control valve, which is interposed between said delivery duct, said discharge duct and said feed duct and which is movable on command between at least one first position, in which said delivery duct is connected to said feed duct in order to contrast the action of said elastic means, and at least one second position, in which said discharge duct is connected to said feed duct in order to avoid contrasting the action of said elastic means, said control valve being a three-way slide valve having three positions and a closed center; safety means for emergency deactivation of the braking system, which comprise auxiliary means for pumping pressurized liquid in said feed duct; said control valve being configured such that, when said feed duct and said delivery duct are mutually disconnected, liquid drawn from said discharge duct fills the accumulator of said pressurized branch, whereby said auxiliary means for pumping pressurized liquid in said feed duct are operable with said control valve in any position: and said safety means comprising a duct for connecting said delivery duct to said discharge duct or to an auxiliary duct which can be connected to an auxiliary reservoir; said auxiliary pumping means being arranged along said connecting duct and being actuatable in order to pump pressurized liquid into said feed duct when said control valve is in said first position.