Method and apparatus for continuous production of reinforced profile belts

Claim 1

A method for continuously producing reinforced profile belts of extruded rubber or plastic material provided with a stretch resistant insert strip, wherein an extruded rubber or plastic material stream passes between two circulating endless loop halves of a divided former which converge along a portion of their lengths to define a closed former segment, comprising the steps of: (a) drawing the insert strip centrally through an extruder outlet to encase it on all sides with a coating of rubber or plastic material, and (b) pulling the coated strip through a straight, closed former segment under tension allowing the coated strip to cool to centrally dispose the strip in a neutral zone of the finished belt and cover the strip on all sides by the rubber or plastic material.

Claim 2

A method for continuously producing reinforced profile belts of extruded rubber or plastic material provided with a stretch resistant insert strip, wherein an extruded rubber or plastic material stream passes between two circulating endless loop halves of a divided former which converge along a portion of their lengths to define a closed former segment, comprising the steps of: (a) drawing the insert strip centrally through an extruder outlet to encase it on all sides with a coating of rubber or plastic material, and (b) pulling the coated strip through a straight, closed former segment under tension allowing the coated strip to cool to centrally dispose the strip in a neutral zone of the finished belt and cover the strip on all sides by the rubber or plastic material.

Claim 4

An apparatus for producing toothed belts having a stretch resistant reinforcing insert strip encased in an extrudable elastic material such as rubber or plastic, comprising: (a) an extruder having an outlet nozzle through which an insert strip may be drawn to encase it in elastic material, and (b) a former disposed downstream of the extruder and including: (1) a pair of endless driven bands each supported around opposing spaced rollers and defining a straight, elongated mold chamber between two adjacent runs of said bands, one of said bands having a toothed outer surface, (2) an inlet funnel disposed at a nip zone between two of said rollers for feeding the encased insert strip into the former, and (3) a pair of converging guide means disposed behind and in engagement with said two adjacent band runs for decreasing the cross-sectional area of the mold chamber in a downstream direction to compensate for shrinkage as the elastic material cools during its passage through the chamber.

Claim 5

An apparatus for producing toothed belts having a stretch resistant reinforcing insert strip encased in an extrudable elastic material such as rubber or plastic, comprising: (a) an extruder having an outlet nozzle through which an insert strip may be drawn to encase it in elastic material, and (b) a former disposed downstream of the extruder and including: (1) a pair of endless driven bands each supported around opposing spaced rollers and defining a straight, elongated mold chamber between two adjacent runs of said bands, one of said bands having a toothed outer surface, (2) an inlet funnel disposed at a nip zone between two of said rollers for feeding the encased insert strip into the former, and (3) a pair of converging guide means disposed behind and in engagement with said two adjacent band runs for decreasing the cross-sectional area of the mold chamber in a downstream direction to compensate for shrinkage as the elastic material cools during its passage through the chamber.