Power Transmission Belt

• US 20080207371A1
• Filed: 03/01/2007
• Published: 08/28/2008
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: Hutchinson (Welltower, Inc.)
• Original Assignee: Hutchinson (Welltower, Inc.)
• Inventors: Sonntag, Philippe, Varin, Herv'e, Dieudonne, Marie
• Granted Patent: US 8,262,522 B2
• Time in Patent Office: Days
• US Class Current: 474/263
• CPC Class Codes: F16G 5/06 with reinforcement bonded by the rubber
• CPC Class Codes: F16G 5/20 with a contact surface of special shape, e.g. toothed

Abstract

The invention relates to a ribbed power transmission belt exhibiting a toothing made of elastomer based on ethylene/α-olefin elastomer, characterized in that at least the sides of the toothing are coated with a film made of at least partially crosslinked thermoplastic comprising at least 30% of at least one low-density polyethylene having a molecular weight of between 50 000 and 200 000 g/mol.

The invention also relates to a manufacturing process which makes use of the application of a said thermoplastic film in the noncrosslinked or at least partially crosslinked state.

Claims

1. A ribbed power transmission belt exhibiting a toothing made of elastomer based on ethylene/α

-olefin elastomer, wherein at least the sides of the toothing are coated with a film made of at least partially crosslinked thermoplastic comprising at least 30% of at least one low-density polyethylene having a molecular weight of between 50 000 and 200 000 g/mol.

2. The belt as claimed in claim 1, wherein said low-density polyethylene has a molecular weight of between 50 000 and 150 000 g/mol.

3. The belt as claimed in claim 1 wherein the degree of crosslinking of the thermoplastic is between 50% and 100%.

4. The belt as claimed in claim 1, wherein said film comprises between 30% and 90% of said low-density polyethylene.

5. The belt as claimed in claim 4, wherein said film comprises between 75% and 90% of said low-density polyethylene.

6. The belt as claimed in claim 1, wherein the film is composed of a blend of polyolefins comprising said low-density polyethylene.

7. The belt as claimed in claim 1, wherein the film is composed of a copolymer based on said low-density polyethylene.

8. The belt as claimed in claim 1, wherein said ethylene/α

-olefin elastomer is an EPDM or an EPM.

9. The belt as claimed in claim 1, wherein the film exhibits a thickness of between 10 μ

m and 500 μ

m.

10. The belt as claimed in claim 1, wherein said film comprises a filler formed of particles of carbon black.

11. The belt as claimed in claim 1, additionally comprising particles and/or fibers which are embedded in said film.

12. The belt as claimed in claim 1, wherein the particles have a particle size and/or the fibers have a length of between 15 μ

m and 200 μ

m, and wherein the fibers having have an aspect ratio between 1 and 100.

13. The belt as claimed in claim 11, wherein at least some particles and/or fibers are made of graphite and/or of molybdenum disulfide and/or of PTFE and/or FEP and/or PFA and/or PVDF.

14. The belt as claimed in claim 11, wherein at least some particles and/or fibers are made of viscose and/or of polyamide, and/or of polyester and/or of polyimide and/or of polysulfone and/or of polyethersulfone and/or of polyetherimide and/or of polyoxymethylene and/or a polyetherketone and/or of acrylic fibers.

15. A process for the manufacture of a ribbed power transmission belt having toothing made of elastomer based on ethylene/α

-olefin elastomer, said process comprising applying in the noncrosslinked or at least partially crosslinked state, to a surface made of toothing rubber a thermoplastic film comprising at least 30% of at least one low-density polyethylene having a molecular weight of between 50 000 and 200 000 g/mol.

16. The process as claimed in claim 15, wherein the applying step is carried out on the toothing rubber in the raw state, before formation of the toothing by molding in a Hydramold and vulcanization of the belt.

17. The process as claimed in claim 16, including incorporating particles and/or fibers are in said film in the noncrosslinked or at least partially crosslinked state.

18. The process as claimed in one claim 16, including depositing particles and/or fibers at the surface of the film in the noncrosslinked or at least partially crosslinked state which are incorporated in the film during the vulcanization of the belt in the Hydramold.

19. The process as claimed in one claim 17, wherein at least some particles and/or fibers are made of graphite and/or of molybdenum disulfide and/or of PTFE and/or FEP and/or PVDF.

20. The process as claimed in one claim 16, wherein at least some particles and/or fibers are made of polyester and/or of polyimide and/or of polyamide, and/or of viscose and/or of polysulfone and/or of polyethersulfone and/or of polyetherimide and/or of polyoxymethylene and/or a polyetherketone and/or of acrylic fibers.