A tray housing driving mechanism 18, further comprising a switch engaging {HEAD ~ said first drawer} to terminate movement at {TAIL ~ an extreme limit} of movement of said first drawer 
A tray housing driving mechanism 18 , further comprising a switch engaging { HEAD ~ said first drawer } to terminate movement at { TAIL ~ an extreme limit } of movement of said first drawer
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH