Toothed belt having a woven fabric layer and method for making the same

Patent metadata

Field	Value
Publication number	US-10962087-B2
Application number	US-201716093090-A
Country	US
Kind code	B2
Filing date	Jan 19, 2017
Priority date	Apr 12, 2016
Publication date	Mar 30, 2021
Grant date	Mar 30, 2021

Abstract

A toothed belt includes a toothed profile made of a base material and defining a toothed profile drive side and a far side facing away from the drive side. A woven ply has a thickness and is applied to the far side of the toothed profile. The woven ply has a first side in contact with the far side causing the base material to penetrate the woven ply at least partly at the first side thereof. The woven ply has a second side facing away from the first side. A coating of plastic on the second side causes the plastic to penetrate the woven ply at least partly at the second side. The base material and the plastic each penetrate the woven ply to an extent to cause the woven ply to be free of the base material and the plastic in an inner lying thickness region thereof.

First claim

The invention claimed is:

1. A method for making a toothed belt from thermoplastic polyurethane, the toothed belt comprising: a toothed profile defining a toothed profile drive side and a far side facing away from said drive side; said toothed profile including a base material; a woven ply having a predetermined thickness and being applied to said far side of said toothed profile; said woven ply having a first side in contact with said far side causing said base material of said toothed profile to penetrate said woven ply at least partly at said first side thereof; said woven ply having a second side facing away from said first side; a coating of polymer on said second side of said woven ply causing said polymer to penetrate said woven ply at least partly at said second side; and, said base material and said polymer each penetrating said woven ply to an extent to cause said woven ply to be free of said base material and said polymer in an inner lying thickness region thereof with reference to said predetermined thickness; the method comprising the steps of:
a) first extruding the base material of the toothed belt;
b) during the extrusion of the corresponding exit die of the extruder, incorporating strengthening elements or tensile elements into the extruded material;
c) forming the resultant precursor together with tensile elements between a forming wheel provided with the negative of the tooth pattern on its outer circumference and a belt that runs around the forming wheel with removal of heat to yield the finished toothed belt, where the belt wraps around the forming wheel over a wrap angle of about 200° under pressure;
d) shortly before the precursor enters the wrapping arc of the forming wheel, running a woven ply onto the forming wheel and then indenting together with the precursor into the shapingly toothed outline of the forming wheel; wherein:
i) the woven ply, on its side facing the forming wheel, before running into the forming wheel, has been provided with a coating of polymer, preferably polyethylene, such that the woven ply has been penetrated up to a penetration depth of 5 to 50% of the ply thickness (weave thickness) by the polymer coating;
ii) the coated woven ply has then been preformed such that it already has essentially the geometry of the toothed form of the forming wheel even before it runs into the forming wheel;
e) intermeshing then the woven ply preformed with the toothed form on the forming wheel and indenting into the shapingly toothed outline of the forming wheel together with the precursor; and,
adjusting the viscosity of the base material of the toothed belt that includes thermoplastic polyurethane such that the polymer-coated woven ply preformed with the toothed form is indented into the precursor such that the woven ply is not penetrated by polyurethane in the inner lying thickness region.

2. The method of claim 1 , wherein the coated woven ply is preformed such that a defined texture or crimping of the warp threads of the weave that forms the woven ply is conserved.

Assignees

• Contitech Antriebssysteme Gmbh

Inventors

• Kucharczyk Andre
• Goeser Hubert

Classifications

• F16G1/28

  with a contact surface of special shape, e.g. toothed · CPC title

• B29D29/08

  Toothed driving belts · CPC title

• F16G1/10 Primary

  with textile reinforcement · CPC title

• B29K2105/0845

  Woven fabrics · CPC title

• B29K2075/00

  Use of {PU, i.e.} polyureas or polyurethanes {or derivatives thereof}, as moulding material · CPC title