Multi-piece Golf Ball Hardness Gradient for Distance and Spin
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Golf balls designed for amateur golfers with moderate head speeds often fall short in achieving optimal distance, spin rate, and feel, particularly when hit with drivers and irons, and lack sufficient scuff resistance.
Innovation Solution
A multi-piece solid golf ball with a rubber core and polyurethane cover, where the surface hardness of the ball is less than or equal to the surface hardness of the intermediate layer-encased sphere, and specific deformation times during impact tests, ensuring a balanced hardness profile and optimal layer thicknesses for enhanced performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the ball is made softer to improve feel and distance for moderate head speeds, then the spin rate on approach shots decreases
Solution Approach 1:
The patent applies local quality by creating distinct hardness zones within the core through the hardness gradient (center hardness 40-55 Shore C, surface hardness 65-80 Shore C). The softer center provides feel and distance for moderate head speeds, while the harder surface maintains spin rate on approach shots. This radial variation in material properties resolves the contradiction between soft feel and high spin rate.
2Reliability
If the cover is made harder to improve scuff resistance, then the feel at impact becomes less soft
Solution Approach 1:
The patent uses composite materials by combining polyurethane cover material with specific hardness characteristics (55-70 Shore D) with an ionomer intermediate layer (40-60 Shore D). This multi-material construction allows the cover to provide scuff resistance while the intermediate layer and core contribute to soft feel, resolving the contradiction between durability and comfort.
3Length of moving object
If the core is made larger to improve distance, then the spin rate on approach shots increases excessively
Solution Approach 1:
The patent applies local quality by creating distinct hardness zones within the core through the hardness gradient (center hardness 40-55 Shore C, surface hardness 65-80 Shore C). The softer center provides feel and distance for moderate head speeds, while the harder surface maintains spin rate on approach shots. This radial variation in material properties resolves the contradiction between soft feel and high spin rate.
4Device complexity
If the intermediate layer is made thinner to reduce complexity, then the balance between distance and spin rate deteriorates
Solution Approach 1:
The patent uses parameter changes by optimizing the intermediate layer thickness to 0.5-1.5 mm and adjusting its hardness (40-60 Shore D) to achieve the right balance. This specific parameter range allows the intermediate layer to effectively transition energy between the core and cover, maintaining both distance and spin rate performance without excessive complexity.
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
The golf ball achieves superior distance and spin rates, provides a soft feel, and exhibits improved scuff resistance, making it suitable for amateur golfers and extending its usability.
Implementation Method 1
the sum t1+t2 of the time t1 required from contact initiation between the driver and the ball for deformation of the ball to reach a maximum value and the time t2 required from the state of maximum ball deformation for the ball and driver clubface to separate is at least 705 microseconds
Data Source
AI summary
In a multi-piece solid golf ball having a core formed of a rubber composition, an intermediate layer formed of a polyurethane material and a cover, the ball satisfies the following condition: surface hardness of ball≤surface hardness of intermediate layer-encased sphere. When the ball is struck with a driver at a head speed of 40 m/s, the sum of the time t1 required from contact initiation between the driver and ball for deformation of the ball to reach a maximum value and the time t2 required from the state of maximum ball deformation for the ball and driver clubface to separate is at least 705 microseconds. This ball has an excellent flight performance when hit by low or moderate head-speed golfers, is receptive to spin on approach shots and has a good, soft feel at impact.