US 4,432,549 · Granted 1984-02-21
The Hollow Metal Golf Club That Changed Driver Design Forever
Before this patent, golf drivers were made solid or used wood. This invention showed how to cast a hollow metal driver in two pieces and weld them together, then position the weight strategically so the club doesn't twist or bend as much when you swing. It's basically engineering physics applied to sports equipment.
The plain-English version
What it protects
The claim covers a hollow golf driver made from cast metal (like stainless steel) that's built in two main pieces—one forming most of the club head with an opening, and a second piece that slots in and welds shut. What's specifically protected is the weight distribution method: making the driver heavier toward the sole (bottom) and toward the toe (outer end), which reduces twisting and deflection during the swing. Anyone manufacturing a hollow metal driver using this exact two-piece casting-and-welding approach with this weight-distribution strategy would be infringing.
Why it matters
This patent arrived during golf's transition from wood-headed clubs to metal, capturing a key manufacturing insight: hollow construction allowed manufacturers to redistribute mass precisely, improving performance and consistency. By controlling where weight sits in the club head, designers could reduce torque (unwanted rotation) and deflection (bending), which directly translates to straighter, more forgiving shots. This foundational approach became central to modern driver design across the industry.
Real-world use
Every modern metal golf driver in a pro shop or sporting goods store uses variations of this hollow, weight-distributed design principle—you can see the larger sole and strategic dimpling or backing that positions mass exactly where this patent describes.
Original USPTO abstract
An all metal hollow golf driver is formed by casting a first main part from metal, e.g., stainless steel, in the shape of practically a complete golf driver, except for an opening on one side of the driver body, e.g., the sole side. A second cast part fits within the opening and is weldable thereto to form a complete integral hollow metal golf driver. The weight (mass) of the driver is distributed in order to reduce its torque and/or deflection. The mass is distributed so that it increases from the top side toward the sole side and from the heel end toward the toe.
Patent details
- Publication number
- US 4,432,549
- Filing date
- 1979-01-26
- Grant date
- 1984-02-21
- Assignee
- Pro-Pattern, Inc.
- Inventor(s)
- ZEBELEAN; JOHN
- CPC class
- A63B53/04
Want to file your own patent?
Curious how golf equipment innovations get protected before they hit store shelves? Use our free patent scanner to see what's already claimed in the fitness-sports space before developing your next equipment idea.
Free patentability scan