Vehicle suspension spring device and vehicle suspension system having the same

A vehicle suspension spring device comprising:

• a leaf spring unit including a plurality of leaf springs disposed and connected in a lateral direction of a vehicle, and a connection part provided to connect the plurality of leaf springs;
• a pair of first coupling parts provided at opposite ends of the leaf spring unit in a longitudinal direction and rotatably coupled to a pair of axles on which opposite wheels of the vehicle are mounted;
• and
• a pair of second coupling parts provided at two points between the opposite ends of the leaf spring unit in the longitudinal direction to be rotatably coupled to a subframe of the vehicle,
• wherein a first coupling part of the pair of first coupling parts is provided at an outer end of an outermost leaf spring of the plurality of leaf springs,
• wherein a second coupling part of the pair of second coupling parts is provided between the plurality of leaf springs,
• wherein the connection part includes a pair of connection members provided at ends of the plurality of leaf springs corresponding to each other and coupled to each other, and a fastening member for coupling the connection members,
• wherein the fastening member is fastened in a front-rear direction of the vehicle to couple the connection members,
• wherein an elastic body is provided to elastically support the connection members in the front-rear direction of the vehicle, and includes a first rubber bushing installed in the connection part to support the fastening member,
• wherein a rotation shaft is coupled to the subframe in the front-rear direction of the vehicle,
• wherein the second coupling part includes a second rubber bushing provided to rotatably support the rotation shaft, and a bushing coupling hole provided on the leaf spring unit so that the second rubber bushing is coupled, and
• wherein the second rubber bushing elastically supports the leaf spring unit around the bushing coupling hole and the subframe.