Conveyor idler and support structure and methods for constructing the same
This invention provides an idler for use in conveyor systems and associated shaft and support structure that reduces the potential for infiltration of contaminants into the bearing assemblies at the opposing ends of the shaft. By use of stampings, co-molded polymer with sealed metal end caps, press-fit end shafts and stamped-metal support structures a more contamination-resistant and efficiently constructed idler assembly is provided. A hollow shaft center section can be used. The polymer defines at least three sealing structures. The shaft defines a multi-piece unit, with the end shafts press-fit onto the center shaft section and held in place by the bearing subassemblies—affixed to the idler sleeve. The support framework includes three stamped and/or cut, and folded sheet metal pieces—a center section with a pair of opposing central risers that engage end shafts, and two opposing, separately attached, end risers, that engage outermost idler end shafts.
1. An idler for a conveyor comprising:
a shaft having shaft ends extending outwardly from each of opposing ends of the idler;
a bearing assembly operatively connected to the shaft and an idler sleeve;
end caps that are, respectively, affixed to the idler sleeve at each of the opposing ends, the end caps including a co-molded polymer seal that rotatably engages each of the shaft ends, the polymer seal defining at least three discrete sealing structures that prevent contaminants from outside the end caps from confronting the bearing assembly, the at least three discrete sealing structures defining a rotating non-contacting seal between each of the end caps and respective of the shaft ends, a rotating labyrinth seal half that confronts a stationary, intermeshed labyrinth seal half and a stationary contacting seal on the intermeshed labyrinth seal half that confronts a rotating face of the subassembly.
2. The idler as set forth in claim 1 wherein the end caps, subassembly and co-molded polymer seal are constructed and arranged to capture contaminants on an inner surface of the idler sleeve remote from the bearing assembly using centrifugal force.
3. The idler as set forth in claim 2 wherein the shaft further comprises a center section between the shaft ends, wherein the center section of the shaft defines one of a hollow and a solid core shaft and the shaft ends are press-fit onto opposing ends of the center section.
4. The idler as set forth in claim 3 wherein each of the shaft ends define either (a) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from inside-out, (b) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from outside-in, or (c) a two-piece unit with a bearing seat onto which the bearing assembly is press-fit from each of opposing directions.
5. The idler as set forth in claim 1 wherein the subassembly defines a pair of confronting stampings, one of which is affixed to the idler sleeve on an inside surface thereof, the stampings together defining opposing drawn pockets that receive the bearing assembly therein in a press-fit.
6. The idler as set forth in claim 1 wherein the shaft further comprises a center section between the shaft ends, and wherein the center section is hollow and includes a sensor operatively connected with a processor that determines at least one of status and performance of the idler.
7. A shaft assembly for supporting an idler comprising:
a center section constructed from at least one of a hollow tube and a solid core shaft; and
a pair of shaft ends, press-fit around the outer diameter of each of opposing ends of the center section, the shaft ends including seats for bearing assemblies, respectively, wherein the bearing assemblies are adapted to rotatably support an idler sleeve.
8. The shaft assembly as set forth in claim 7 wherein the shaft ends each include a surface, outward of the bearing seat, that confronts a seal of an end cap, the end cap being affixed adjacent to a respective outer end of the sleeve.
9. The shaft assembly as set forth in claim 8 wherein the bearing assemblies are interconnected to subassemblies that extend to, and are affixed to, an inside surface of the sleeve.
10. The shaft assembly as set forth in claim 7 wherein each of the shaft ends define either (a) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from inside-out, (b) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from outside-in, or (c) a two-piece unit with a bearing seat onto which the bearing assembly is press-fit from each of opposing directions.
11. The shaft assembly as set forth in claim 10 wherein (a) includes a flange to stop axial motion of the bearing assembly, located on a side of the bearing assembly that is inward toward the center section, (b) includes a flange to stop axial motion of the bearing assembly, located on a side of the bearing assembly that is outward from the center section, or (c) includes a flange on each of two pieces, engage each side of the bearing assembly.
12. The shaft assembly as set forth in claim 7 wherein the shaft ends are constructed from a powdered/sintered metal.
13. The shaft assembly as set forth in claim 7 wherein an outer end of each of the shaft ends includes a keyway slot for engaging a riser in a support frame.
14. The shaft assembly as set forth in claim 13 wherein at least one of the shaft ends defines a distally extended keyway, with at least one flat and the riser includes a receiving slot that fully surrounds and conforms to a shape of a cross section of the keyway when the keyway is inserted axially into the receiving slot.
15. An idler for a conveyor comprising:
a shaft having shaft ends extending outwardly from each of opposing ends of the idler; and
a bearing assembly operatively connected to each of the shaft ends respectively, and the bearing assembly being operatively connected, via a subassembly, to an idler sleeve, the subassembly defining a pair of confronting stampings, one of which is affixed to the idler sleeve on an inside surface thereof, the stampings together defining opposing drawn pockets that receive the bearing assembly therein in a press-fit.
16. The idler of claim 15 , further comprising end caps that are, respectively, affixed to the idler sleeve at each of the opposing ends, the end caps including a co-molded polymer seal that rotatably engages each of the shaft ends.
17. The idler of claim 16 , wherein the polymer seal defines at least three discrete sealing structures that prevent contaminants from outside the end caps from confronting the bearing assembly.
18. The idler of claim 17 , wherein the at least three discrete sealing structures define a rotating non-contacting seal between each of the end caps and respective of the shaft ends, a rotating labyrinth seal half that confronts a stationary, intermeshed labyrinth seal half and a stationary contacting seal on the intermeshed labyrinth seal half that confronts a rotating face of the subassembly.
19. The idler as set forth in claim 18 wherein the end caps, subassembly and co-molded polymer seal are constructed and arranged to capture contaminants on an inner surface of the idler sleeve remote from the bearing assembly using centrifugal force.
20. The idler as set forth in claim 19 wherein the shaft further comprises a center section between the shaft ends, wherein the center section of the shaft defines one of a hollow and a solid core shaft and the shaft ends are press-fit onto opposing ends of the center section.
21. The idler as set forth in claim 20 wherein each of the shaft ends define either (a) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from inside-out, (b) a one-piece unit with a bearing seat onto which the bearing assembly is press-fit from outside-in, or (c) a two-piece unit with a bearing seat onto which the bearing assembly is press-fit from each of opposing directions.
22. The idler as set forth in claim 15 , wherein the shaft further comprises a center section between the shaft ends, and wherein the center section is hollow and includes a sensor operatively connected with a processor that determines at least one of status and performance of the idler.