In FIG 9, angular relationships between {HEAD ~ a dust bag} 34 and {TAIL ~ walls} 65, 65 of a housing 63 are achieved by creating a non rectangular housing 
In FIG 9 , angular relationships between { HEAD ~ a dust bag } 34 and { TAIL ~ walls } 65 , 65 of a housing 63 are achieved by creating a non rectangular housing
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH