Until the invention of the Phillips screw, American assembly lines, craftsmen, and consumers used regular, slotted-head screws. But that design was problematic for three reasons: it was difficult to align the driver with the screw aperture; the driver tended to slip from the open ends; and the slot required a closely matching bit. The cruciform drive addressed those problems. Although the Phillips screw became ubiquitous through its usefulness on the assembly line, it is unknown whether Thompson or Phillips originally intended the invention to specifically solve the challenges presented by regular head screws in manufacturing.
Thompson's original patent for a "Screw driver" U. S patent , filed by Phillips in and granted in , mentions driving "either by hand or by power-driven types of tool. By , twenty companies had licenses to produce Phillips screws worldwide.
By then the Phillips screw was in use by nearly every major American automobile manufacturer, as well as by railroad and airplane builders.
As the war effort gave, however, it also took away. Phillips Screw Company depended on licensing the design to foreign manufacturers to grow, and World War II restricted the countries that the company could reliably do business with.
In , for example, one licensee, the J. Osawa Company, was ramping up production in Kyoto, Japan; but by Japan had broken off trade relations with the United States, likely making it difficult for Phillips to collect license fees. Henry Phillips retired in In , the U. They were charged with patent pooling, cartel practices, price-fixing, and the suppression of competing technologies.
The case, United States v. Phillips Screw Co. District Court of Northern Illinois Chicago. The case was concluded in with a consent decree that dissolved the patent pool, likely making it difficult to protect the collection of patents that the company relied upon to protect its intellectual property. In any case, unlicensed companies had earlier begun to produce similar competing designs, some of which were convinced to buy into the licensing agreement.
Other manufacturers, however, said that their designs were not based on the Phillips design, but on the older, unprotected Frearson design. In the same year, a final refinement was patented on the Phillips drive system by an engineer from the American Screw Company; that patent expired in Henry Phillips died in his home at the Ione Plaza Apartments in Portland on April 13, ; he was sixty-eight years old. Although the Phillips drive system remains far and away the most widely used internal screw-driving system—industry estimates indicate that it is used in at least half of all internally driven screws—it is being steadily replaced by newer technologies.
From its current headquarters in Burlington, Massachusetts, the Phillips Screw Company continues to develop and license drive systems that are replacing its founding technology. A further advantage is that once the screw has reached its maximum torque, the screw driver "cams out": It pops out of the screw so the screw can't be overdriven, and the sides of the slot aren't damaged. It's not clear whether this was intended by design, but it's a helpful feature.
Henry Phillips patented his screwdriver and screw, and the technology related to them in However, the Phillips tool became so ubiquitous that in he lost the patent, although his name has remained linked to both the screwdriver and the screw.
Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Stripped fasteners and damaged screws were a common problem in construction sites before the invention of the Phillips screw.
Regular screws that typically had the mating surface exposed were prone to wear and tear. Adding pressure and further tightening would have only added to the problem and usually implied a potentially dangerous and costly situation. Once the Phillips screw came along, less pressure was applied to the individual points of the fasteners and constructors were able to avoid stripping. Because the Phillips screws integrate cross-shaped grooves over the head, it means builders have a greater surface area to work with.
In addition, the same traits ensure that the pressure is distributed evenly and better, leaving the fastener less exposed to normal wear and tear.
Other noteworthy advantages of the Phillips head screws Thanks to their unique features, the Phillips screws became a common sight in construction sites worldwide.
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