US Patent 10532621 Mounting structure for suspension arm, and working vehicle

A suspension arm A-shaped in a plan view includes legs receiving therebetween front and rear surfaces of a vertical member arranged in a travel direction of a working vehicle. The legs of the suspension arm and the surfaces of the vertical member each have a hole. An attaching structure includes: a cantilevered pin inserted into the hole of each of the legs and the corresponding hole of the vertical member to hold the leg of the suspension arm such that the suspension arm is pivotable; and a retaining mechanism provided to a frame to prevent the pin from coming off the vertical member. The pin includes a projection extending radially outward at a base end in an insertion direction. The retaining mechanism includes: a holding portion holding the projection in a rotation direction of the pin; and a cover portion covering the projection in the insertion direction of the pin.