Coupling device and belt transmission device comprising same

The utility model provides a connecting device and a belt transmission device comprising the same, the connecting device is used for connecting a main shaft and a belt pulley, the connecting device comprises a spline housing body, the spline housing body is a hollow cylinder, and the outer surface of the spline housing body is provided with an outer spline matched with a key groove of the belt pulley; an inner spline matched with a main shaft key groove is arranged on the inner surface of the spline housing body; the supporting bearing sleeves the outer surface of the spline housing body and is used for supporting the spline housing body; the bearing fixing seat is provided with a through cavity extending in the axial direction of the supporting bearing, the through cavity comprises a first through hole and a second through hole which are coaxially arranged, the diameter of the first through hole is larger than that of the second through hole, the first through hole is used for containing the bearing, and the