The support plate may be provided with a rib frame structure including a plurality of ribs in a horizontal direction corresponding to a direction of the first tilt shaft and a plurality of {HEAD ~ ribs} in a vertical direction corresponding to a direction of {TAIL ~ the second tilt shaft} 
The support plate may be provided with a rib frame structure including a plurality of ribs in a horizontal direction corresponding to a direction of the first tilt shaft and a plurality of { HEAD ~ ribs } in a vertical direction corresponding to a direction of { TAIL ~ the second tilt shaft }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL