| 摘要 |
PURPOSE: A variable weight type counterweight is provided to ensure improved strength and efficient use of internal space because a case is made by casting and no scrap is filled in the case. CONSTITUTION: A variable weight type counterweight comprises a cast-iron case(110), an injection port(120), and a discharge valve(130). The cast-iron case, which is installed on heavy equipment, has a hollow structure to be filled with for controlling weight and a thickness to occupy 50~70% of the total weight of the counterweight. The injection port is formed on the top of the cast-iron case to fill water into the internal space of the cast-iron case. The discharge valve is formed on the bottom of the cast-iron case and opened to discharge the water when needed to reduce the weight of the counterweight. |
