Abstract: A coil-winding method comprises: winding first coil clockwise around first, counterclockwise around second, and clockwise around third swath along mandrel, hooks grouped into swaths; winding second coil clockwise around between first arid second hooks of first to between first and second hooks of second swath, counterclockwise around from between first and second hooks of second to between first and second hooks of third swath, clockwise around between first and second hooks of third to between first and second hooks of first swath; winding third coil clockwise around between second and third hooks of first to between second and third hooks of second swath, counterclockwise around from between second and third hooks of second to between second and third hooks of third swath, clockwise around between second and third hooks of third to between second and third hooks of first swath; and releasing wound coils.

Abstract: A coil winding apparatus to fabricate a coil-wound article comprises a mandrel having an outer periphery, first and second side ends through which is axially formed an orifice to define an inner periphery. Slots are radially formed along each side section of the outer periphery to allow communication between the inner and outer peripheries. Grooves are circularly formed to intersect the slots. Upright portions of the hooks are radially aligned with the slots to enable their reciprocal movements through the slots. Retainer members sustain the hooks by the holes. Elastic rings are worn in and along the grooves to elastically maintain each upright portion of the corresponding hooks below the outer periphery of the mandrel. Adjusters are detachably inserted through the orifice to allow the upright portions to remain above the outer periphery of the mandrel.

Abstract: A method of forming a coil-wound article comprises: winding a first coil by laps clockwise around a first swath, counterclockwise around a second swath, and clockwise around a third swath of hooks out of slots along an outer periphery of a mandrel, wherein the hooks are collapsibly protruded from within the mandrel through the slots and consecutively grouped into the first to third swaths each at least having a first to third hook; winding a second coil by laps clockwise around from between the first and second hooks of the first swath to between the first and second hooks of the second swath, counterclockwise around from between the first and second hooks of the second swath to between the first and second hooks of the third swath, and clockwise around from between the first and second hooks of the third swath to between the first and second hooks of the first swath; winding a third coil by laps clockwise around from between the second and third hooks of the first swath to between the second and third hooks