LIGHTWEIGHT REINFORCED CONVEYOR BELT STRUCTURE
Conveyor belts formed of a composite fabric structure. The fabric structure has a base reinforcing layer made of a network that includes high tenacity fibers. The composite fabric structure also includes a surface layer formed of rubber. The base layer and the surface layer are bonded together, preferably through the use of a bonding layer.
1 . A conveyor belt structure comprising
a) at least one surface layer formed of a rubber composition; and
b) a reinforcing base layer formed by a fibrous network having at least 10% high tenacity fibers; and
c) each surface layer bonded to one of the surfaces of the base layer.
2 . The conveyor belt structure of claim 1 wherein the high tenacity fibers have a tenacity of at least about 25 grams per denier and a tensile modulus of at least 1200 grams per denier.
3 . The conveyor belt structure of claim 1 wherein the high tenacity fibers are selected from the group consisting of high modulus polyethylene, aramid, polybenzazole, liquid crystal copolyester, and blends thereof.
4 . The conveyor belt structure of claim 1 wherein the fibrous network includes at least 50% high tenacity fibers.
5 . The conveyor belt structure of claim 1 wherein the fibrous network includes at least 75% of high tenacity fibers.
6 . The conveyor belt structure of claim 1 wherein the fabric base comprises a woven fabric.
7 . The conveyor belt structure of claim 1 wherein the rubber comprises a natural rubber.
8 . The conveyor belt structure of claim 1 wherein the rubber comprises a composition selected from the group consisting of natural rubber and styrene butadiene; natural rubber and polybutadiene; and natural rubber, styrene butadiene and polybutadiene.
9 . The conveyor belt structure of claim 1 wherein the surface layer is bonded to the reinforcing base layer by a thermoplastic material.
10 . The conveyor belt structure of claim 9 wherein the high tenacity fibers are high molecular weight polyethylene fibers and the rubber comprises a blend of 80% natural rubber and 20% styrene butadiene.
11 . The conveyor belt structure of claim 1 and further including a bonding layer between the base layer and each surface layer.
12 . The conveyor belt structure of claim 11 wherein the bonding layer comprises ethylene vinyl acetate.
13 . The conveyor belt structure according to claim 1 wherein a surface layer formed of a rubber composition is bonded to each surface of the reinforcing base layer by a bonding layer.
14 . The conveyor belt structure according to claim 1 wherein the structure comprises multiple reinforcing base layers separated by at least one layer of the rubber composition.
15 . A conveyor system comprising
a) a conveyor belt arranged around a support structure and driven by a drive mechanism;
b) a drive mechanism connected to and driving the support system for moving the conveyor belt between a loading end and a discharge end;
c) the conveyor belt comprising
i) at least one surface layer formed of a rubber composition;
ii) a reinforcing base layer formed by a fibrous network having at least 25% high tenacity fibers; and
iii) each surface layer bonded to one of the surfaces of the base layer.
16 . The conveyor system of claim 15 wherein the high tenacity fibers have a tenacity of at least about 25 grams per denier and a tensile modulus of at least 1200 grams per denier.
17 . The conveyor system of claim 15 wherein the high tenacity fibers are selected from the group consisting of high modulus polyethylene, aramid, polybenzazole, liquid crystal copolyester, and blends thereof.
18 . The conveyor system of claim 15 wherein the fibrous network includes at least 50% high tenacity fibers
19 . The conveyor system of claim 15 wherein the fibrous network includes at least 75% of high tenacity fibers.
20 . The conveyor system of claim 15 wherein the high tenacity fibers comprise ultra high molecular weight polyethylene fibers.
21 . The conveyor system of claim 15 wherein the fabric base comprises a woven fabric.
22 . The conveyor system of claim 15 wherein the rubber comprises a natural rubber.
23 . The conveyor system of claim 15 wherein the rubber comprises a composition selected from the group consisting of natural rubber and styrene butadiene; natural rubber and poly butadiene; and natural rubber, styrene butadiene and poly butadiene.
24 . The conveyor system of claim 15 wherein the surface layer is bonded to the reinforcing base layer by a thermoplastic material.
25 . The conveyor system of claim 24 wherein the fabric base comprises high molecular weight polyethylene fibers and said rubber comprises natural rubber.
26 . The conveyor belt structure of claim 25 and further including a bonding layer between the base layer and each surface layer.
27 . The conveyor system of claim 26 wherein the bonding layer comprises ethylene vinyl acetate.
28 . The conveyor system according to claim 15 wherein a surface layer formed of a rubber composition is bonded to each surface of the reinforcing base layer by a bonding layer.
29 . The conveyor system according to claim 15 wherein the conveyor belt comprises multiple reinforcing base layers separated by at least one layer of the rubber composition.