Elastomer-free fabric surface for power transmission belt tooth facing
AssigneeThe Gates Rubber Company
InventorJohn D. Redmond, Jr.
Life of this patent
Estimating the term…
Abstract
An endless positive drive belt is described having a tensile-loaded castable elastomeric body supporting circumferentially spaced cogs or teeth. The alternating land and teeth portions of the belt carry a layer of wear-resistant fabric, the outer surface of which is free of elastomer due to the preferred presence of a bonded layer of elastomer impervious material during the casting operation. A method for producing the belt using the elastomer impervious material is described.
Claims16
In an endless positive drive power transmission belt comprising a body portion composed of a liquid cast elastomeric material, a tensile layer disposed longitudinally within the body portion and forming a bond therewith, a plurality of spaced teeth bonded with and disposed along the inner periphery of the body portion to form alternating teeth and land portions, and a layer of wear-resistant fabric positioned substantially along the periphery of said alternating land and teeth portions of the belt, the improvement comprising a layer of elastomer impervious material bonded so it adheres to at least a portion of the total thickness of the wear-resistant fabric and positioned along the outer, sprocket-engaging face of the teeth and land portions of the belt, adapted and arranged such that the sprocket-engaging face of the belt is substantially free of cast elastomer and exhibits a relatively low coefficient of friction compared with the cast elastomer.
In an endless positive drive power transmission belt comprising a body portion composed of a liquid cast polyurethane material, tensile cord disposed longitudinally within the body portion and forming a bond therewith, a plurality of spaced teeth bonded with and disposed along the inner periphery of the body portion to form alternating teeth and land portions and a layer of wear-resistant polyamide fabric positioned substantially along the periphery of said alternating teeth and land portions of the belt, the improvement comprising a thin layer of polymeric sheeting impervious to the flow of polyurethane during casting of the belt, said polymeric sheeting bonded to one side only of the wear-resistant nylon fabric and positioned along the outer, sprocket-engaging face of the teeth and land portions of the belt, the outer surface of the wear-resistant fabric being substantially free of the cast polyurethane to a depth of at least 20% below the outer surface of the wear-resistant polyamide fabric.
An endless positive drive power transmission belt adapted to be engaged in a cooperating sprocket(s) comprising:
- a body portion comprising a liquid cast elastomer material;
- a tensile section embedded within the body portion and extending longitudinally with respect to the intended direction of travel of the belt;
- a plurality of spaced teeth disposed along the inner periphery of the body portion and containing said elastomeric material therein;
- a band of wear-resistant fabric comprised of fibers positioned along the outer surface of the teeth, the fibers on the outermost, sprocketengaging surface of the fabric band being substantially free from total encapsulation by said elastomeric material.
In a polyurethane liquid cast positive drive power transmission belt having a polyurethane body, a tensile section disposed within said body, and a series of polyurethane-containing teeth integral with the body and positioned along the inner peripheral surface of the belt and having an outer fabric surface bonded to the teeth as well as land portions between the teeth, the improvement comprising:
- said fabric having an outer, sprocket engaging surface substantially free of polyurethane, the coefficient of friction of said sprocketengaging surface being substantially less than the coefficient of friction of the polyurethane.
In a cast positive drive power transmission belt having a cast elastomeric body, a tensile section disposed within said body, and a plurality of cogs integral with the body and positioned in spaced relation along the inner periphery sprocket-engaging surface of the belt and having a fibrous fabric cover formed on the cogs, the improvement comprising:
- an outermost at least partially removable layer attached to said fabric cover which is impervious to the cast elastomer and which isolates the cast elastomer from the outer surface of the cogs to the extent that the outermost fibers of the fabric cover are substantially free from total encapsulation by the cast elastomer.
In a positive drive power transmission belt having an elastomeric body portion, a tensile band embedded in the body, and a plurality of teeth integral with the body and containing an elastomeric material which is of the same or different material as said elastomeric body portion and which possesses a determined coefficient of friction, the teeth being positioned along the inner periphery sprocket-engaging surface of the belt and having a fibrous cover formed over the teeth and land portions between the teeth, the improvement comprising:
- said fibrous cover having its outer, sprocket-engaging surface substantially free of said elastomeric material of the teeth, said free outer surface of the fibrous cover exhibiting a coefficient of friction which is substantially less than the determined coefficient of friction of the elastomeric material of the teeth.
Dependencies are inferred from the claim text.