adj.成直角的(正交的)
Wall type:the exterior of fan has two terminals ,one side is bell-mouthed type, the other side is 90 degree rightangle flange type. 壁式：风扇外形两端一边是喇叭口型，一边是90.
Some Netizen said that, the train hard place designs nobody nature tomanifest in two points: One is the seat back cushion has the rightangle; 有网友说，火车硬座设计无人性化体现在两点：一是靠背成直角；
