V-ribbed belt with improved noise properties
V-ribbed belts are formed by thermoplastic shaping and contain ribs that run at least on a first side in a longitudinal direction of the V-ribbed belt. The first side contains a layer composed of a textile warp-knit fabric made up of two different yarns. The warp-knit fabric is constructed from a first yarn composed of filaments with a module of more than 5N/1000 dtex, and a second yarn composed of filaments with a module of less than 2 cN/1000 dtex, both based on 5% extension. The first and second yarns form a coherent network and the yarns do not twine around one another. V-ribbed belts can be formed using an elastic warp-knit fabric, whose extension is based on the construction of the knitted fabrics. The belts maintain better noise reduction both in the new state and after a relatively long service life.
1. A V-ribbed belt ( 1 ) of elastomer material ( 2 ) with embedded tensile load-bearing elements ( 3 ),
which has ribs ( 5 ) of a substantially wedge-shaped cross section that extend at least on one side in the longitudinal direction of the V-ribbed belt ( 1 ) and are formed by thermoplastic shaping,
and this first side has a layer of a textile warp-knitted fabric ( 7 ) comprising two different yarns ( 12 , 13 ),
wherein the warp-knitted fabric ( 7 ) is constructed from a first yarn ( 12 ) composed of filaments with a modulus of more than 5N/1000 dtex, based on 5% extension, and
a second yarn ( 13 ) composed of filaments with a modulus of less than 2 cN/1000 dtex, based on 5% extension,
the first yarn ( 12 ) and the second yarn ( 13 ) in each case forming a coherent network and the yarns ( 12 , 13 ) not being twined around one another and wherein the warp-knitted fabric ( 7 ) is constructed in counternotation.
2. The V-ribbed belt as claimed in claim 1 , wherein the second yarn ( 13 ) is an elastane with a weight per length ratio of 2 to 6 dtex.
3. The V-ribbed belt ( 1 ) as claimed in claim 1 , wherein the warp-knitted fabric ( 7 ) is knitted with two guide bars on the basis of the following pattern, namely guide bar 1 ( 16 ) with the first yarn ( 12 ) in closed plain weave of the sequence 1-0-1/1-2-1 and guide bar 2 ( 17 ) with the second yarn ( 13 ) in closed tricot weave of the sequence 2-3-2/1-0-1.
4. The V-ribbed belt ( 1 ) as claimed in claim 1 , wherein a noise-reducing antifriction coating ( 8 ) is applied to the warp-knitted fabric ( 7 ).
5. The V-ribbed belt ( 1 ) as claimed in claim 4 , wherein the noise-reducing antifriction coating ( 8 ) is made of a color other than that of the warp-knitted fabric ( 7 ) or the elastomer material ( 2 ).
6. The V-ribbed belt ( 1 ) as claimed in claim 4 , wherein the noise-reducing antifriction coating ( 8 ) is constructed from a flexible carrier layer and low friction particles.
7. The V-ribbed belt ( 1 ) as claimed in claim 6 , wherein the flexible carrier layer predominantly consists of polyurethane.
8. The V-ribbed belt ( 1 ) as claimed in claim 6 , wherein the low friction particles consist of fluorine-containing polymers.
9. The V-ribbed belt ( 1 ) as claimed in claim 6 , wherein the low friction particles consist of PTFE.
10. The V-ribbed belt ( 1 ) as claimed in claim 1 , wherein the V-ribbed belt ( 1 ) has ribs ( 6 ) of a substantially wedge-shaped cross section extending on their second side, opposite from the first side, in the longitudinal direction of the V-ribbed belt ( 1 ), which ribs are formed from the elastomer material of the V-ribbed belt ( 1 ) by machining.
11. The V-ribbed belt ( 1 ) as claimed in claim 10 , wherein the V-ribbed belt ( 1 ) has ribs ( 6 ) of a substantially wedge-shaped cross section extending on their second side, opposite from the first side, in the longitudinal direction of the V-ribbed belt ( 1 ), which ribs are formed from the elastomer material of the V-ribbed belt ( 1 ) by grinding.
12. The V-ribbed belt ( 1 ) as claimed in claim 1 , wherein the warp-knitted fabric ( 7 ) has an electrical conductivity.
13. The V-ribbed belt ( 1 ) as claimed in claim 12 , wherein the warp-knitted fabric has an electrically conductive surface coating of a vapor-deposited metal.
14. The V-ribbed belt ( 1 ) as claimed in claim 12 , wherein the warp-knitted fabric ( 7 ) is constructed from electrically conductively coated yarns ( 12 , 13 ).
15. The V-ribbed belt ( 1 ) as claimed in claim 14 , wherein the electrically conductive yarns ( 12 , 13 ) are vapor-coated with a metal.
16. The V-ribbed belt ( 1 ) as claimed in claim 15 , wherein the electrically conductive yarns ( 12 , 13 ) are vapor-coated with silver.