There is provided a motor including a rotating member coupled with a shaft and rotating in connection with the shaft, and a fixing member having the shaft inserted thereinto to support the shaft and including a round part whose outer surface corresponding to the rotating member is formed to be rounded to thereby allow oil to be sealed between the round part and the rotating member. Adjacent to the hermetic joint, there is a gap between adjacent surfaces of the body and sensor unit, which gap facilitates an easier assembling procedure and which facilitates transportation of gases away from the hermetic joint zone when the body and sensor unit is assembled e. A pair of pull ropes extends through the housing and the slats, and connects the shaft to the bottom rail.