Description     Claims     Drawing  

US3220392A   [0004] 
US3367312A   [0006] 
US3786792A   [0007]  [0010] 
US3809033A   [0008]  [0009] 
US5564385A   [0009] 
US6234143B   [0010] 
US6253730B   [0011]  [0016] 
US3520287A   [0013] 
US4572114A   [0014]  [0016] 
US20050211206A   [0015] 
US20070175441A   [0015] 
CN2011001505W   [0016] 
US20100170472A1   [0017]