Die cushion apparatus
US6804983B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2002 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Jun 26, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21D24/02
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A gas cushion apparatus with a support member to 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 into an oil chamber communicating with the oil chamber on the side of the 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.