Abstract: A rotational coupling includes a hub assembly configured for rotation about a rotational axis. The hub assembly includes a hub disposed about the axis and configured to receive a shaft and a disc extending radially outwardly from the hub. An armature and electromagnet are disposed on opposite axial sides of the disc. The electromagnet is fixed against rotation. A bearing is disposed between the hub and the electromagnet. The hub assembly and electromagnet are separated by an air gap on an outboard side of the bearing. A debris shield is axially aligned with, and extends across the radial length of, the air gap and, in some embodiments, is at least partially disposed within the air gap. The shield has a fixed end coupled to one of the hub assembly and electromagnet during assembly and a free end configured to engage the other through a spring force and/or electromagnetic attraction.

Abstract: A bobbin wound coil for an electromagnetic coupling includes a bobbin having a cylindrical body disposed about a central axis, end flanges disposed at each axial end of the body and a terminal connector on an exterior side of one of the end flanges. The terminal connector includes a body defining a central cavity and a post extending from an exterior surface of the body of the terminal connector. A coil includes a beginning portion extending through the body of the terminal connector and the end flange on which the terminal connector is located, an end portion extending through the body of the terminal connector and the end flange, and a center portion extending between the beginning portion and the end portion and wound about the cylindrical body of the bobbin. One of the beginning portion and the end portion of the coil is wound about the post.

Abstract: A bobbin wound coil for an electromagnetic coupling includes a bobbin having a cylindrical body, end flanges disposed at opposite ends of the body and a terminal connector defining a central cavity bordered, in part, by inner and outer walls and a side wall extending between the inner and outer walls. A coil has a beginning portion extending through first openings in the inner and outer walls, an end portion extending through second openings in the inner and outer walls, and a center portion wound about the bobbin body. The first and second openings in the inner wall divide the inner wall into first and second circumferential end sections and a center section. A portion of one of the circumferential end sections and the center section is spaced from the side wall to define a recess configured to receive one of the beginning and end portions of the coil.

Abstract: A bobbin wound coil for an electromagnetic coupling includes a bobbin having a cylindrical body, end flanges disposed at opposite ends of the body and a terminal connector on an exterior side of one of the end flanges. A coil has a beginning portion extending through first openings in the terminal connector and an end flange and an end portion extending through second openings in the terminal connector an end flange. The second openings in the terminal connector and end flange are forward and rearward, respectively, of the corresponding first openings in a circumferential direction. A section of the beginning portion extends between the first openings in the terminal connector and end flange and a section of the end portion extends between the second openings in the terminal connector and end flange such that section of the end portion crosses over the section of the beginning portion.