Description     Claims  

US3804763A   [0002]  [0003]  [0016] 
US4031118A   [0002]  [0004]  [0016] 
GB2111526A   [0002]  [0005]  [0016] 
DE2360117A   [0003] 
US2002032127A   [0003] 
US4466894A   [0008]