Cogged V-Belt Manufacturing with Post-Vulcanization Cog Forming

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing methods for manufacturing cogged V-belts result in non-uniform flowing of unvulcanized rubber sheets, leading to recesses and potential cracks or peeling issues at the interface between rubber layers, which compromises the durability and reliability of the belt.

Innovation Solution

A method involving the formation of a vulcanized sleeve by laminating unvulcanized rubber sheets with short fibers oriented in the belt width direction, followed by cog formation using a water jet-processing machine, ensuring uniformity and preventing peeling between layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If unvulcanized rubber sheets are pressurized to flow and form cogs, then cogged V-belt structure is formed, but non-uniform flowing occurs causing recesses and potential cracks or peeling at rubber layer interfaces

Engineering Contradiction:
Improvecog formation processVSAvoiduniformity of rubber layer thickness
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by forming cogs after vulcanization rather than during the pressing process. The unvulcanized rubber sheets are first laminated uniformly, then vulcanized to create a stable structure, and finally cogs are formed on the vulcanized sleeve. This sequence prevents the non-uniform flowing and recess formation that occurs when attempting to form cogs during the pressing of unvulcanized rubber.

Inventive Principle:
Principle #10Preliminary action

2Shape

If unvulcanized rubber sheet flows into concave portion of drum, then cog shape is formed, but non-uniform flowing causes recesses on belt outer peripheral side

Engineering Contradiction:
Improvecog shape formationVSAvoiduniformity of compression rubber layer thickness
Core Design Contradiction:
ShapeVSManufacturing precision

Solution Approach 1:

The patent forms the cog shape after vulcanization by processing the vulcanized sleeve, rather than attempting to form the shape by flowing unvulcanized rubber into drum concavities. This approach ensures uniform thickness throughout the compression rubber layer while still achieving the desired cog shape, eliminating the recess formation problem.

Inventive Principle:
Principle #10Preliminary action

3Ease of manufacture

If compression rubber layer is formed by flowing unvulcanized rubber sheet, then belt structure is created, but cracks and peeling occur at interface with other rubber layers

Engineering Contradiction:
Improvebelt structure formationVSAvoidinterface bonding between rubber layers
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent performs vulcanization before forming cogs, which creates a stable, cross-linked rubber structure. This preliminary vulcanization prevents the non-uniform flowing that causes recesses and interface separation, thereby maintaining strong bonding between the compression rubber layer and other rubber layers while still enabling cog formation.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent inverts the conventional sequence by forming cogs after vulcanization rather than before. This reversal ensures that the rubber layers are already bonded and stabilized through vulcanization, preventing cracks and peeling at interfaces during the cog formation process.

Inventive Principle:
Principle #13The other way round (Inversion)

4Strength

If short fibers are oriented in belt width direction, then lateral pressure resistance is improved, but manufacturing complexity increases

Engineering Contradiction:
Improvelateral pressure resistanceVSAvoidfiber orientation control
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent achieves fiber orientation in the belt width direction by controlling the parameters of the vulcanization and subsequent cog formation processes. The specific combination of vulcanization temperature, pressure, and timing, followed by water jet processing, creates the desired fiber alignment that enhances lateral pressure resistance without requiring complex additional equipment.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances the lateral pressure resistance and durability of the cogged V-belt, reducing the occurrence of cracks and peeling, thereby improving the belt's performance under high loads and in continuously variable transmission systems.

Implementation Method 1

the plurality of cogs are formed in the compression rubber layer by a water jet-processing machine

Methodology Applied
Scientific EffectJet Erosion: Jet Erosion

Implementation Method 2

a vulcanized sleeve formation step of vulcanizing the unvulcanized sleeve after the unvulcanized sleeve formation step, thereby forming a vulcanized sleeve

Methodology Applied
Scientific EffectVulcanization:

Data Source

PatentEP3505791B1Method for manufacturing cogged v-belts
Publication Date: 2023.11.22 MITSUBOSHI BELTING LTD
  • EP3505791B1 patent drawingFigure 1
  • EP3505791B1 patent drawingFigure 2
  • EP3505791B1 patent drawingFigure 3

AI summary

The present invention pertains to a method for manufacturing cogged v-belts that are provided with, on the inner circumference of a belt, a plurality of cogs that are disposed to extend in the width direction of the belt and to be spaced apart from each other in the belt longitudinal direction, wherein the method for manufacturing cogged v-belts comprises: a unvulcanized sleeve forming step of forming an unvulcanized sleeve by layering a plurality of unvulcanized rubber sheets that contain at least an unvulcanized rubber sheet for a compression rubber layer that is a compression rubber layer disposed on the inner circumferential side of the belt and an unvulcanized rubber sheet for an expansion rubber layer that is an expansion rubber layer disposed on the outer circumferential side of the belt; a vulcanized sleeve forming step of forming a vulcanized sleeve by vulcanizing the unvulcanized sleeve after the unvulcanized sleeve forming step; and a cog forming step of forming the plurality of cogs on the compression rubber layer after the vulcanized sleeve forming step.