US2899246A
US2899246A US2899246DA US2899246A US 2899246 A US2899246 A US 2899246A US 2899246D A US2899246D A US 2899246DA US 2899246 A US2899246 A US 2899246A Authority US United States Prior art keywords swing jaw shafts shaft bushing Prior art date Legal status (The legal status is an assumption and is not a legal conclusion.