when said support frame is at the closed position, the upper ends and {HEAD ~ the lower ends} of {TAIL ~ said oblong holes} of said side support frame are so positioned as to maintain a predetermined gap relative to said coupling shaft; and 
when said support frame is at the closed position , the upper ends and { HEAD ~ the lower ends } of { TAIL ~ said oblong holes } of said side support frame are so positioned as to maintain a predetermined gap relative to said coupling shaft ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH