Tyre-changing machine bead breaking with non-rolling contact surfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional tyre-changing machines often damage tyres and rims during the bead breaking process, especially with run-flat tyres, due to intense force application and localized pressure, leading to potential perforation, cuts, and increased risk of breakage.
Innovation Solution
A tyre-changing machine with two adjustable support arms equipped with non-rolling contact surfaces that apply force symmetrically and incrementally along a large contact area to detach both beads simultaneously, reducing the risk of damage and allowing for secure multiple fittings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If traditional bead breaking devices apply intense force to detach the bead, then the bead detachment is achieved, but the tyre and rim may be damaged due to concentrated localized pressure
Solution Approach 1:
The bead breaking operation is divided into multiple sequential stages with progressively increasing force. The device applies force in increments rather than a single intense application, allowing the bead to detach gradually while distributing the mechanical stress over time and area, thereby preventing sudden concentrated pressure that could damage the tyre or rim.
Solution Approach 2:
The bead breaking device features adjustable and movable components that adapt to different tyre sizes and bead positions. The force application point can be dynamically repositioned around the tyre circumference, and the pressing force can be adjusted based on the specific tyre type (including run-flat tyres), allowing optimized force distribution that prevents localized damage while achieving effective bead detachment.
2Force
If pneumatic or hydraulic arms are used to press the tool against the bead, then the bead can be detached, but the procedure is time-consuming and requires multiple operations
Solution Approach 1:
The device combines multiple bead breaking operations into a single integrated tool that can work on both beads simultaneously or in rapid succession. The dual-arm design with coordinated movement allows the operator to detach both beads without requiring separate pneumatic or hydraulic arm operations, significantly reducing the total time required for the bead breaking procedure.
Solution Approach 2:
The bead breaking process is made continuous through the device design that maintains constant contact and progressive force application around the tyre. The movable arms and adjustable mechanisms allow uninterrupted working on both beads without requiring repositioning or resetting of equipment, eliminating idle time and maintaining continuous productive action throughout the bead breaking operation.
3Productivity
If rollers are used to apply force on the rotating tyre, then the bead can be detached, but the concentrated localized forces increase the risk of tyre damage
Solution Approach 1:
Instead of using rollers that concentrate force on small localized areas, the device segments the force application across multiple contact points around the bead circumference. The tool distributes the breaking force through a broader contact area using flattened or curved pressing surfaces, reducing peak stress concentrations that could cause tyre damage while maintaining effective bead detachment through cumulative force distribution.
Data Source
AI summary
The tyre-changing machine (10) for fitting and removing vehicle wheels comprises: - a bed (12) for resting on the ground; - a spindle (14) which extends from the bed (12) and on which is mountable a wheel (R) having a rim (C) and a tyre (PN) with two opposite flanks (F1, F2), the spindle (14) being configured to tighten the rim (C) on it and able to put in rotation the wheel (R) around an axis of rotation (A); and - two bead breaking tools (32, 42) which are movable one towards the other in the proximity of the spindle (14) along a bead-breaking direction (D1) substantially parallel to the axis of rotation (A) of the spindle (14), the bead breaking tools (32, 42) having respective non-rolling contact surfaces (34, 44) able to contact and push in use the opposite flanks (F1, F2) with the wheel (R) mounted on the spindle (14).