Description     Claims     Drawing  

US2664852A   [0003] 
WO2012081738A   [0003]  [0005] 
US3059612A   [0004] 
US3581766A   [0005] 
WO2013143692A   [0005] 
GB1220020A   [0006] 
WO2015067662A   [0007]  [0010] 
US3408224A   [0009]