High temperature flexible thermoplastic composites for endless belt driving surfaces
AssigneeThe Gates Corporation
InventorsScott L. Ciemniecki, Ronald A. L. Rorrer, Harry D. Visser
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Abstract
Endless belts having driving surfaces comprising a high temperature flexible thermoplastic composite. More particularly, an endless toothed belt having a high temperature-, abrasion- and noise resistant cover element, and which comprises from about 60 percent to about 100 percent by weight of the composite of a high temperature flexible thermoplastic material and from about 0 percent to about 40 percent by weight of the composite of a frictional modifier system, and methods for constructing such belts. Such belts include elastomeric body portions which may preferably be formed from suitable polyurethane materials.
Claims28
An endless belt having a driving surface portion, and characterized in that said driving surface portion comprises a high temperature flexible thermoplastic composite, said high temperature flexible thermoplastic composite having a melting point higher than about 150° C., and comprising from about 60 percent to about 100 percent by weight based on the total weight of said composite of a high temperature flexible thermoplastic material, and from about 0 percent to about 40 percent by weight based on the total weight of the composite of a frictional modifier system.
An endless toothed belt, comprising;
- a. a tensile-loaded body portion comprising an elastomeric material;
- b. a plurality of spaced teeth bonded with and disposed along the inner periphery of said body portion;
- and
- c. a layer of wear-resistant fabric positioned substantially along the periphery of the alternating teeth and land portions of said belt, and characterized in that a high temperature flexible thermoplastic composite layer is positioned substantially along and bonded to at least a portion of the outer surface of said wear-resistant fabric, said composite layer exhibiting a lower coefficient of friction than that of said elastomeric material, and a melting point greater than about 150° C., said high temperature flexible thermoplastic composite comprising from about 60 percent to about 100 percent by weight based on the total weight of said composite of a high temperature flexible thermoplastic material, and from about 0 percent to about 40 percent by weight based on the total weight of said composite of a frictional modifier system.
In an endless toothed belt, comprising;
- a) a tensile-loaded body portion comprising a polyurethane/urea elastomer;
- b) a plurality of spaced teeth bonded with and disposed along the periphery of said body portion;
- c) a layer of wear-resistant fabric positioned substantially along the periphery of the alternating teeth and land portions of said belt;
- the improvement comprising a high temperature flexible thermoplastic composite layer positioned substantially along and bonded to at least a portion of the outer surface of the wear-resistant fabric and forming the driving surface of said belt, said composite layer exhibiting a lower coefficient of friction than said polyurethane/urea elastomer, and a melting point greater than about 150° C., said high temperature flexible thermoplastic composite comprising a flexible nylon 6-based alloy and from about 15 percent to about 18 percent by weight based on the total weight of said composite of a frictional modifier system comprising polytetrafluoroethylene.
In an endless toothed belt, comprising;
- d) a tensile-loaded body portion comprising polyurethane/urea elastomer;
- e) a plurality of spaced teeth bonded with and disposed along the periphery of said body portion;
- f) a layer of wear-resistant fabric positioned substantially along the periphery of the alternating teeth and land portions of said belt;
- the improvement comprising a high temperature flexible thermoplastic composite layer positioned substantially along and bonded to at least a portion of the outer surface of the wear-resistant fabric and forming the driving surface of said belt, said composite layer exhibiting a lower coefficient of friction than said polyurethane/urea elastomer, and a melting point greater than about 150° C., said high temperature flexible thermoplastic composite comprising a flexible nylon 6-based alloy and a frictional modifier system comprising from about 15 percent to about 20 percent by weight based on the total weight of said composite of polytetrafluoroethylene, and from about 1 percent to about 2 percent by weight based on the total weight of said composite of silicone.
In a process for constructing an endless toothed belt having a tensile-loaded body portion comprising a castable polyurethane material, a plurality of spaced teeth bonded with and disposed along the periphery of said body portion, a layer of wear-resistant fabric positioned substantially along the periphery of the alternating teeth and land portions of said belt, comprising the steps of:
- a) bonding a laminate layer to at least one side of a wear-resistant fabric layer;
- b) forming a notched mold cavity defined by a mold mandrel and an outer shell having a notched portion;
- c) wrapping the bonded wear-resistant fabric about a surface of the mold cavity such that the laminate layer is adjacent the notched mold portion;
- d) applying a tensile layer about said wear-resistant fabric;
- e) introducing a substantially liquid castable polyurethane material into said mold cavity, and;
- f) polymerizing said polyurethane material to form a belt, the improvement comprising said laminate layer being in the form of a high temperature flexible thermoplastic composite, said composite exhibiting a lower coefficient of friction than that of said elastomeric material, and a melting point greater than about 150° C., said high temperature flexible thermoplastic composite comprising from about 60 percent to about 100 percent by weight of said composite of a high temperature flexible thermoplastic material and from about 0 percent to about 40 percent by weight of said composite of a frictional modifier system.
Dependencies are inferred from the claim text.