Patent ID: 6041597
Filing Date: 2000-03-28
Classification: B23Q,Y10S

Abstract:
A balance weight system for a unit, comprising:a cylinder,a piston rod having a first end adapted to be secured to the unit to move therewith, the piston rod further including a second end with a piston head slidably received in the cylinder and separating the cylinder into a lower chamber for containing hydraulic oil and an upper chamber for containing air,a tank including hydraulic oil contained in a lower part thereof and a working gas contained in an upper part thereof,a tube having a first end in the hydraulic oil in the lower part of the tank and a second end communicated with the lower chamber of the cylinder, the working gas exerting a pressure on the hydraulic oil to supply the piston rod with a force sufficient to uphold the unit, andmeans for moving the unit in a vertical direction.