US 4,042,443 A · Flexible matrix for forming a portion of a toothed power transmission belt

Abstract

A method and assembly for making a power transmission belt having driving teeth on opposite surfaces thereof and a tensile member embedded therein. The disclosure also relates to a belt made by the method and apparatus. The method includes providing separate toothed belt portions which will form the two halves of the belt, positioning the first belt portion on a grooved mandrel with the teeth of the first portion disposed within the grooves of the mandrel, applying a tensile member over the outer periphery of the non-toothed surface of the first portion, positioning the other belt portion over the tensile member with its toothed surface facing outwardly of the mandrel; aligning the teeth of the second portion in a predetermined position relative to the teeth of the first portion, retaining the configuration of the teeth of the second portion relative to the teeth of the first portion; and curing the belt portions into a molded integral structure with teeth on opposite surfaces and preferably having a wear-resistant facing covering the opposite toothed surfaces. The disclosed assembly includes means such as a grooved mandrel for maintaining the tooth configuration in the first belt portion and a flexible grooved matrix of special construction for maintaining the tooth configuration in the second belt portion.

Claims16

Dependent claims

A flexible grooved matrix used in combination with a rigid grooved mandrel for forming and retaining the tooth configuration of belt driving teeth of a previously formed toothed belt portion of a toothed power transmission belt, said matrix comprising:

A. a generally cylindrical body of flexible polymeric material;
B. reinforcing means including at least one circumferentially disposed reinforcing member embedded in said body;
C. an inwardly facing surface having a plurality of tooth-forming and retaining grooves disposed therein, said grooves extending generally axially of said matrix and having a plurality of lands alternating therewith with said grooves being of an opposite configuration to that of the teeth of the toothed belt portion so as to register therewith;
and
D. means at each axial end for registering and aligning said matrix grooves with the teeth of said previously formed toothed belt portion, said means comprising a plurality of teeth disposed in outer rows at each axial outer end of the matrix extending circumferentially thereof with each tooth extending axially thereof on said inwardly facing surface, said teeth being of an opposite configuration to that of the grooves of the mandrel so as to register therewith and protruding radially inwardly beyond the surface of said lands and said grooves and said lands extending axially between said outer rows.

2 more elements

In the manufacture of a toothed power transmission belt having transversely extending teeth on opposite surfaces thereof, the combination of:

A. a rigid cylindrical mandrel having a plurality of grooves in its outer peripheral surface extending axially thereof;
B. a first preformed belt portion of flexible polymeric material having a plurality of driving teeth on one surface thereof, said first belt portion surrounding said mandrel to form an endless belt sleeve with the teeth of said first portion lying within the grooves of the mandrel, said belt sleeve having a width less than the axial length of the mandrel so that a portion of the outer peripheral surface of the mandrel at each end is exposed;
C. a second preformed belt portion of flexible polymeric material having a plurality of driving teeth in one surface thereof, said second belt portion surrounding said first belt portion to form an endless belt sleeve with the teeth of said second portion facing outwardly of the mandrel, said belt sleeve having a width less than the axial length of the mandrel so that a portion of the outer peripheral surface at each end of the mandrel is exposed;
D. a flexible grooved generally cylindrical matrix surrounding said second portion, said matrix having a plurality of teeth provided in one surface thereof, said teeth disposed in outer rows at each axial end of the matrix with the teeth of each row extending axially of the matrix and facing inwardly of the mandrel, and a plurality of lands and grooves on the inwardly facing surface thereof extending axially between said rows of teeth, the teeth of said matrix having an opposite configuration to that of the grooves of the mandrel and the grooves of the matrix having an opposite configuration to that of the teeth of said second belt portion, said matrix having a greater axial length than the first and second belt portions and the teeth of said matrix protrude radially inwardly beyond the surface of said lands so that the teeth of said matrix face inwardly of the mandrel and mesh with the grooves of the mandrel in the exposed surface thereof and the grooves of said matrix mesh with the teeth of said second belt portion.

1 more element

Dependencies are inferred from the claim text.

Flexible matrix for forming a portion of a toothed power transmission belt

Life of this patent

Flexible matrix for forming a portion of a toothed power transmission belt

Life of this patent

Abstract

Claims16