Sliding Cam Assembly Diffusion Bonding Wear Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for manufacturing sliding cam assemblies result in increased material and tooling costs due to excessive machining, and non-uniform hardness issues arise from electron beam hardening, particularly affecting the low cam near the high cam due to shadow effects.
Innovation Solution
A method involving separately forming and coupling a hollow tubular portion with a guide piece and cam piece using diffusion bonding, where the cam piece is fixed to the hollow tubular portion, allowing for optimal physical properties and minimizing machining waste and heat treatment, with a spiral guide groove on the guide piece for enhanced durability and cost-effectiveness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If a sliding cam and fixed cam are manufactured by machining a raw material in the shape of a round rod to conform to the shape of the cam, then the cam shape is achieved, but the machining quantities are excessively increased, which causes an increase in material costs and tooling costs
Solution Approach 1:
The cam is divided into two separate components: a hollow tube and a cam piece. The hollow tube is formed by extrusion or drawing processes, while the cam piece is separately manufactured and then coupled to the hollow tube. This segmentation allows each component to be optimized for its specific manufacturing process, reducing material waste and machining requirements.
Solution Approach 2:
The manufacturing approach changes from machining a solid round rod to a combination of extrusion/drawing for the hollow tube and separate cam piece fabrication. This parameter change in the manufacturing process significantly reduces material removal and machining quantities while achieving the required cam shape.
2Strength
If electron beam hardening (EBH) is performed on a material having been subjected to machining to improve the hardness of the surface of the cam, then the surface hardness is improved, but the hardness of a portion of the low cam close to the high cam is not uniform with other portions due to a shadow effect
Solution Approach 1:
The cam is segmented into a hollow tube and a cam piece that is coupled to it. The cam piece can be separately heat-treated to achieve uniform hardness without the shadow effect problem that occurs with the integrated cam design, as the separate piece allows for more controlled and uniform heat treatment processes.
Solution Approach 2:
The hollow tube acts as an intermediary structure that carries the cam piece. This separation allows the cam piece to be independently heat-treated with uniform hardness, while the hollow tube provides the structural framework, thus solving the non-uniform hardness issue caused by the shadow effect in integrated cam designs.
3Ease of manufacture
If a cam piece and guide piece are integrally formed and coupled to a hollow tubular portion through forced coupling and shape coupling, then the components are assembled, but the wear resistance requirement of the hollow tubular portion is not satisfied during repeated sliding
Solution Approach 1:
The coupling method changes from forced coupling and shape coupling to diffusion bonding. This parameter change in the joining process creates a metallurgical bond that provides superior wear resistance compared to mechanical coupling methods, while still allowing for separate manufacturing of the components.
Solution Approach 2:
The assembly creates a composite structure where the hollow tube, guide piece, and cam piece are joined through diffusion bonding. This composite construction combines the advantages of separate component manufacturing with the superior performance of a bonded joint, achieving both ease of manufacture and high wear resistance.
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 reduces machining time and costs, ensures wear resistance, and allows for optimal physical properties in the sliding cam assembly, maximizing durability and minimizing manufacturing expenses by enabling separate machining and eliminating the need for separate heat treatment.
Implementation Method 1
a cam piece 30 and a hollow tubular portion 10 which are coupled to each other through diffusion bonding
Data Source
AI summary
Disclosed is a method of manufacturing a sliding cam assembly. In particular, a requirement for wear resistance of a hollow tubular portion in which sliding takes place can be satisfied due to a cam piece being fixed to the hollow tubular portion by diffusion bonding while the sliding cam assembly repeatedly slides along a shaft, and each component can be separately machined and combined, thus minimizing an amount which is wasted at the time of machining, reducing the machining time, and rendering a separate heat treatment of a cam piece unnecessary.