Method for fabricating molded coil
View Patent ↗There is provided a system for readily and efficiently fabricating a wound coil composed of a bobbinless coil. The system includes a coil winding device having an upper jig to which an upper plate is attached and a lower jig to which a lower plate is attached which are provided so as to be relatively displaceable and a tension device for applying predetermined tension to a wire rod fed from a wire rod supplying source. The coil winding device is provided with a claw section having first through third split claws that function as a winding section around which the wire rod is wound between the upper and lower plates and that slide in a radial direction when the upper jig is assembled coaxially with the lower jig.
1. A coil winding method for forming a stacked coil by winding a wire rod supplied from a nozzle to a claw section provided between upper and lower plates, wherein an upper jig to which the upper plate is attached is coaxially joined with a lower jig to which the lower plate is attached and the upper and lower jigs are supported so as to be integrally rotated in a predetermined direction, comprising steps of:
drawing the wire rod along a guide groove formed on an under surface of the lower plate after securing a winding beginning portion of the wire rod by a first winding securing section of the lower plate;
forming the stacked coil by winding the wire rod around the peripheral surface of the claw section after drawing the wire rod from an outer peripheral portion of the lower plate to an inner peripheral portion thereof by exposing the wire rod from an under surface of the lower plate to an upper surface thereof; and
securing a winding ending portion of the wire rod to a second winding securing section of the lower plate after drawing the wire rod from the inner peripheral portion to the outer peripheral portion along the upper surface of the lower plate;
wherein the winding beginning portion of the wire rod secured to the first winding securing section and the winding ending portion of the wire rod secured to the second winding securing section are disposed so as to cross from each other at the upper and under surfaces of the lower plate.
2. The coil winding method as set forth in claim 1 , wherein a plurality of projections that project in the radial outward direction is provided around the outer peripheral portion of the upper plate, a plurality of projections that project in the radial outward direction is provided around the outer peripheral portion of the lower plate, the projections of the upper and lower plates are disposed so as not to be vertically superimposed, the projections of the upper plate and the projections of the lower plate are woven alternately along a peripheral direction by a weaving wire after securing the winding ending portion of the wire rod to the second winding securing section of the lower plate.
3. The coil winding method as set forth in claim 1 , wherein the claw section is composed of a plurality of split claws and at least one split claw has a groove formed so as to guide the wire rod along the peripheral direction.