Claims
- 1. A doffer unit for cotton picking machines comprising a hub portion adapted to drivingly engage a driveshaft, a ring portion concentric with said hub portion and a plurality of circumferentially spaced, radially extending lugs carried by said ring and disposed on one planar side of said unit and wherein said doffer lugs are comprised of a vulcanized millable polyurethane elastomer.
- 2. The doffer unit of claim 1 wherein said millable polyurethane elastomer is sulfur cured.
- 3. The doffer unit of claim 1 wherein said millable polyurethane elastomer is peroxide cured.
- 4. The doffer unit of claim 1 wherein the polyurethane in said millable polyurethane elastomer is a polyether or polyester based polyurethane.
- 5. The doffer unit of claim 1 wherein said polyurethane is a polyester type.
- 6. The doffer unit of claim 1 wherein said vulcanized polyurethane elastomer has a tensile strength of between about 3800 to 4200 psi., a modulus at 300% extension of 900 to 1800 psi, an elongation at break of about 350 to 650, a Shore A hardness of 60-75 and a DeMattia flexure of less than about 30/32 inch after 35,000 cycles.
- 7. The doffer unit of claim 1 wherein said doffer lugs are formed by injection molding of said millable polyurethane elastomer.
- 8. The doffer unit of claim 1 wherein said millable polyurethane elastomer is compression molded at a temperature ranging from about 280.degree. F. to about 310.degree. F. for about 15 to 30 minutes.
- 9. The doffer unit of claim 1 wherein said millable polyurethane elastomer is derived from a formulation comprised of a polyester-urethane having a number average molecular weight of between about 10,000 to 50,000 in combination with a sulfur or peroxide curing agent, accelerator, activator, lubricant and a filler.
- 10. A cotton picking unit having a plurality of doffers and arranged to doff cotton and associated matter from a plurality of cooperating spindles, said doffers comprising a doffer unit for cotton picking machines comprising a hub portion adapted to drivingly engage a drive shaft, a ring portion concentric with said hub portion and a plurality of circumferentially spaced, radially extending lugs carried by said ring and disposed on one planar side of said unit and wherein said doffer lugs are comprised of a vulcanized millable polyurethane elastomer.
Parent Case Info
This application is a continuation of application Ser. No. 595,334, filed Mar. 30, 1984, now abandoned.
US Referenced Citations (6)
Continuations (1)
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Number |
Date |
Country |
Parent |
595334 |
Mar 1984 |
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