determining means for determining {TAIL ~ a criterial position} of the ejector pins where the detected elastic force of the springs is equivalent to {HEAD ~ the retaining force} of the brake means; and 
determining means for determining { TAIL ~ a criterial position } of the ejector pins where the detected elastic force of the springs is equivalent to { HEAD ~ the retaining force } of the brake means ; and
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH