| 摘要 |
A gas cushion apparatus is provided with a support member that can hold a blank, gas pressure cylinders that push the support member upwards, a hydraulic cylinder whose upper rod is connected to the support member, a pneumo- hydraulic converter for secondary lifting with a piston that partitions the interior thereof into an oil chamber communicating with the oil chamber on the side of the aforementioned rod of the hydraulic cylinder and a gas chamber, a check valve that allows oil to flow from the oil chamber on the side opposite to the above-mentioned rod to the oil chamber on the side of the aforementioned rod, and a drain port communicating with the oil chamber on the side of the above-mentioned rod of the hydraulic cylinder; when the die passes the bottom dead center point, the drain port is closed, and when the die is traveling from the bottom dead center point to the top dead center point, the pressure in the gas chamber of the pneumo-hydraulic converter for secondary lifting is decreased, thus the piston is moved to the gas chamber side.
|
