Method and apparatus for assembly of cassette pulley

Apparatus for assembling a cassette pulley including a hub part and a flange part, said hub part having a plurality of recesses arranged around a hub center and wherein some of said recesses are formed with a hub assembly hole, said flange part having a plurality of projecting pins each adapted to be received in a respective one of the assembly holes of the hub part when the hub and flange parts are relatively oriented about the hub center in a selected assembly orientation, said apparatus comprising:

• a hub holder having a plurality of hub holding stub shafts adapted to be received in hub recesses for holding and orienting a hub part in any one of a predetermined number of orientations,
• an alignment sensing aperture in said hub holder positioned with respect to the hub holding stub shafts for alignment with an aperture in a hub part when such hub part is in at least one of said orientations thereof and positioned to be out of alignment with all of the holes in the hub part when the hub part is in another of said orientation thereof,
• an orientation sensing station,
• means for moving said hub holder to said orientation sensing station,
• means at said orientation sensing station for directing a light beam along a path extending through the alignment sensing aperture of a hub holder at said station,
• sensor means at said orientation sensing station for receiving a light beam passing through said hub holder aperture,
• an assembly station,
• a flange holder at said assembly station,
• means at said assembly station for feeding a flange to said flange holder with a predetermined orientation,
• means for moving said hub holder to said assembly station,
• means at the assembly station responsive to said light sensor means for controlling relative orientation of said hub and flange parts to a predetermined assembly orientation, and
• means at the assembly station for assembling the flange part to the hub part.

A method of assembling a cassette pulley having a pulley flange part in the form of a substantially flat disc having a plurality of assembly pins mutually spaced about a disc center and projecting from the plane of the disc, and including a pulley hub part having a plurality of radial reinforcing ribs extending radially from a hub center and dividing the hub into a plurality of recessed areas, alternate ones of said recessed areas having an assembly hole, and each of said assembly holes configured and positioned to receive a respective one of said assembly pins of said cassette pulley flange part when said parts are in one of a selected group of relative orientations about an orientation axis extending axially of said hub part, said method comprising the steps of:

• loading the hub part upon a hub support in one orientation of first and second groups of orientations,
• projecting a light beam along a sensing path at an orientation detection station,
• moving the hub support and thereby moving a hub part on the hub support along a path in which one of the holes in a hub part on the support intersects said sensing path if the hub part on the hub support at said orientation detection station is in an orientation of said first group of orientations, and wherein none of the holes in the hub part on the hub support intersect the sensing path when the hub part is in an orientation of said second group of orientations,
• detecting passage of said light beam through a hole in a hub part on said hub support at said orientation detection station,
• moving the hub support and a hub part thereon to an assembly station,
• loading a flange part upon a flange support at the assembly station with a predetermined assembly orientation, and
• changing the relative orientations of said hub support and flange support according to whether or not passage of a light beam through a hole in a hub part was detected.

For use with a cassette pulley hub part having a plurality of mutually adjacent recesses circularly arranged around the center of the hub part, some of said recesses having assembly holes and the others having no assembly holes, a method of orienting the hub part to align the assembly holes with assembly pins of a flange that is to be assembled to the hub part, said method comprising the steps of:

• loading the hub part upon a hub part holder having a plurality of holder stub shafts respectively received in different ones of said recesses to thereby hold the hub part on the holder in one orientation of first and second groups of orientations with respect to the holder,
• providing an alignment hole in the holder between some of said holder stub shafts,
• directing a light beam along a path extending through the alignment hole of the holder, and
• determining whether or not the light beam passes through the holder alignment hole to thereby signal whether or not an assembly hole of the hub part is in alignment with the alignment hole, one of said alignment holes being aligned with the hub part holder alignment hole in each position of said first group of orientations and said alignment hole being blocked by said hub part in each position of said second group of positions of said hub part relative to said holder, whereby detection of passage of the light beam through the alignment hole indicates a relative orientation of the hub part with respect to the holder that is one of said first group of orientations.

A method of assembling a cassette pulley having a flange part and a hub part, said parts being required to have a predetermined relative rotational orientation about an orientation axis for assembly of the parts to one another, a first one of said parts having a hole there through, said method comprising the steps of:

• loading said first part upon a support having a hole therein,
• holding the first part on the support in one of a group of different orientations about the orientation axis, said support hole being aligned with the hole in said first part when said first part is in at least one of said different orientations,
• sensing alignment of the hole in the first part with the hole in the support, thereby sensing if the first part on the support has one orientation or another relative to the support, and
• controlling relative orientation of the flange part and hub part according to sensed alignment of said holes.