Patent ID: 7878422
Filing Date: 2011-02-01
Classification: F15B

Abstract:
1. A variable dampening rate suspension system for a vehicle and a boom sprayer vertically movably mounted on the vehicle and oriented transversely to a direction of travel of the vehicle, which suspension system includes: a hydraulic system with a hydraulic pressure source; a pair of lift assemblies each including upper and lower lift arms with proximate and distal ends, each lift arm being connected at its proximate end to said vehicle and at its distal end to said boom sprayer; each said lift assembly including a hydraulic lift cylinder connected to the vehicle and the boom sprayer and adapted for vertically moving the boom sprayer relative to the vehicle structure by extending and retracting; a diaphragm-type hydraulic accumulator connected to the hydraulic pressure source and the lift cylinder; and a hydraulic flow restrictor valve disposed between and fluidly connected to the accumulator and the lift cylinder for variably restricting flow therebetween; said flow restrictor valve being adjustable between closed and open positions and providing for variable flow rates of hydraulic fluid therethrough; said flow restrictor valve comprising a needle valve including an adjustment knob and adapted for providing a firmer ride in a more closed position and a softer ride in a more open position; and a control block connected to said hydraulic pressure source, said lift cylinder and said restrictor valve, said control block controlling hydraulic fluid flow from said pressure source to said lift cylinder and said restrictor valve.