Patent ID: 6144907
Filing Date: 2000-11-07
Classification: B60G

Abstract:
Apparatus comprising:a construction machine vehicle having a left front tire, a right front tire, a left rear tire, and a right rear tire, each of said tires having a spring constant;a left front suspension cylinder mounted on a left front side of said vehicle; said left front suspension cylinder having a cylinder chamber for absorbing vibration of said left front tire by an internal pressure of the cylinder chamber of said left front suspension cylinder;a right front suspension cylinder mounted on a right front side of said vehicle, said right front suspension cylinder having a cylinder chamber for absorbing vibration of said right front tire by an internal pressure of the cylinder chamber of said right front suspension cylinder;at least one change-over valve;at least one accumulator, each accumulator being connected through one of said at least one change-over valve to at least one of said left front suspension cylinder and said right front suspension cylinder;a vehicle speed sensor for sensing a speed of said vehicle and providing a speed signal responsive thereto; anda controller for receiving said speed signal, for comparing a vehicle speed, as represented by said speed signal, with a vehicle speed setting range, and for actuating said at least one change-over valve to provide fluid communication between each one of said left front suspension cylinder and said right front suspension cylinder and one of said at least one accumulator if said vehicle speed is within said vehicle speed setting range, thereby altering a characteristic frequency of each of said left front suspension cylinder and said right front suspension cylinder.