A hybrid holding device used in a milling machine, comprising a base with mounting structures for detachably fastening the hybrid holding device securely onto a workbench of the milling machine in a fixed stationary position. The hybrid holding device further includes moveable multi-jaw assembly that includes at least three jaws that directly receive and securely hold a workpiece without an adapter.

A wheel rim chuck has a chuck seat (10) and multiple soft jaws (20). The soft jaws are arranged radially at equiangular intervals and slidably mounted on the chuck seat (10). Each soft jaw (20) has a claw (21) having a protrusion (211), a clamping groove (213), and an inclined plane (216). The protrusion (211) protrudes from a side of the soft jaw (20) away from the chuck seat (10). The clamping groove (213) is recessed in a side of the protrusion (211) facing the center (111) of the chuck seat (10) and having a side wall (214) and a bottom wall (215). The inclined plane (216) extends longitudinally and obliquely from the bottom wall (215) away from the side wall (214) of the clamping groove (213).

A hybrid holding device used in a milling machine, comprising a base with mounting structures for detachably fastening the hybrid holding device securely onto a workbench of the milling machine in a fixed stationary position. The hybrid holding device further includes moveable multi-jaw assembly that includes at least three jaws that directly receive and securely hold a workpiece without an adapter.