초록 ▼

An active suspension system for use with a mass suspended relative to a movable structure and subject to external forces such as the chassis of off-road vehicles, and in particular the hull of heavy combat vehicles, has a passive hydropneumatic suspension system (PHSS) connected to a servopump and a

An active suspension system for use with a mass suspended relative to a movable structure and subject to external forces such as the chassis of off-road vehicles, and in particular the hull of heavy combat vehicles, has a passive hydropneumatic suspension system (PHSS) connected to a servopump and an accumulator, and wherein the servopump transfers fluid energy between the accumulator and the suspension system, in accordance with sensed operating conditions which are inputted to a processor whose output commands the velocity of the servopump to control the pressure and volume relationships of the PHSS and accumulator to improve the ride of said vehicle and to substantially reduce energy requirements when operating off-road.

대표청구항 ▼

An active hydropneumatic suspension system for a sprung mass of a vehicle supported on the unsprung mass of a roadwheel, the active hydropneumatic suspension system statically supporting the sprung mass of a vehicle with a predetermined force and at a predetermined position relative to the unsprung

An active hydropneumatic suspension system for a sprung mass of a vehicle supported on the unsprung mass of a roadwheel, the active hydropneumatic suspension system statically supporting the sprung mass of a vehicle with a predetermined force and at a predetermined position relative to the unsprung mass of the roadwheel while dynamically controlling force between the sprung mass of the vehicle and the roadwheel so as to control the position of the sprung mass of the vehicle when subject to the motion of the roadwheel, to inertial force acting on the sprung mass of the vehicle as the vehicle is driven, and to external force acting on the sprung mass of the vehicle as the vehicle is either driven or is stationary, comprising: a passive suspension system means for resiliently supporting said sprung mass of the vehicle at the predetermined static position including a hydraulic actuator having a first volume of pressure fluid at a predetermined static pressure; said hydraulic actuator having a first end and a second end; said first end connected to said sprung mass of the vehicle and said second end connected to said roadwheel; servopump means for transferring fluid; a hydropneumatic accumulator separate from said passive suspension system; said hydropneumatic accumulator containing a volume of pressure gas having a static pressure equal to the static pressure of the pressure fluid in said hydraulic actuator and said hydropneumatic accumulator further having a second volume of pressure fluid; first and second fluid conduit means for connecting said passive suspension system means, said servopump means and said hydropneumatic accumulator in series fluid flow relation; pressure conditioning means including said hydropneumatic accumulator for resiliently equilibrating said servopump means and said servopump means including means for transferring pressure fluid between said first volume of pressure fluid in said hydraulic actuator of said passive suspension system means and said second volume of pressure fluid in said hydropneumatic accumulator; power supply means for providing an energy requirement to control and to drive said servopump means for transferring pressure fluid between said hydraulic actuator and said hydropneumatic accumulator which energy requirement is proportional to the differential pressure across said servopump means between said first and second fluid conduit means whereby pressure in either said hydraulic actuator or said hydropneumatic accumulator serves to balance pressure across said servopump means for reducing the energy required to operate said servopump means during transfer of pressure fluid by said servopump means between said first volume of pressure fluid in said hydraulic actuator of said passive suspension system and said second volume of pressure fluid in said hydropneumatic accumulator; detector means for sensing one or more motions including the absolute motion of said sprung mass of the vehicle, the absolute motion of said roadwheel and the relative motion of said sprung mass of the vehicle to said roadwheel; and control system means operative in response to said sensed motions for conditioning said servopump means to vary flow of pressure fluid by said servopump means between said first and second fluid conduit means to control the transfer of pressure fluid between said first volume of pressure fluid in said hydraulic actuator of said passive suspension means and said second volume of pressure fluid in said hydropneumatic accumulator to dynamically control the force acting between said sprung mass of said vehicle and said roadwheel for controlling the relative position of said sprung mass of said vehicle to said roadwheel at low frequencies of relative motion between said sprung mass of said vehicle and said roadwheel to thereby improve equilibration of said sprung mass of the vehicle so as to improve vehicle handling and for controlling the absolute position of said sprung mass of the vehicle at higher frequencies of motion of either or both of said sprung mass of said vehicle and said roadwheel to thereby improve stabilization and isolation of said sprung mass of the vehicle so as to improve the ride quality of vehicle while minimizing the energy requirements during operation of said servopump means to be proportional to the pressure differential across said servopump means rather than proportional to a higher absolute pressure in said hydraulic actuator.