The evolution of screws and screwdrivers

The evolution of screws and screwdrivers

The evolution of screws and screwdrivers

A screw is any rod that has a corkscrew groove in its surface. Screws are used to hold two objects together. A screwdriver is a tool that turns (turns) a screw; A screwdriver has a point that fits over the head of a screw.

Early screw

Spiral tools became common around the first century AD, but historians don't know who invented them first. Early screws were made from wood and were used in wine presses, olive oil presses, and pressing clothes. The metal screws and nuts used to hold two things together first appeared in the fifteenth century.

In 1770, English toolmaker Jesse Ramsden (1735–1800) invented the first satisfactory screw-cutting lathe and became an inspiration to other inventors. In 1797, Englishman Henry Maudslay (1771-1831) invented a large screw-cutting lathe that could be used to mass-produce screws of precise dimensions. In 1798, the American mechanic David Wilkinson (1771-1652) also invented a machine for the mass production of metal-threaded screws.

Robertson screw

In 1908, Canadian P. L. Robertson (1879-1951) invented the square-drive screw, 28 years before Henry Phillips applied for a patent on his Phillips-head screw, which is also a screw with square shank. The Robertson screw is considered "the first grooved fastener available for manufacturing use". The design became a North American standard published in the Industrial Fastener Standards Book. The square head on the screw is an improvement over the slotted head because the screwdriver does not slip out of the screw head during installation. An early 20th century Model T built by Ford Motor Company (one of Robertson's early customers) used over seven hundred Robertson propellers.

Phillips screws and other enhancements

In the early 1930s, Oregon businessman Henry Phillips (1889–1958) invented the Phillips screw. Automakers now use car assembly lines. They need screws that can handle higher torques and provide tighter tightening. Phillips head screws are compatible with automatic screwdrivers used on assembly lines.

The hex or hex head of a screw has a hex hole that can be turned with a hex wrench. A hex wrench (or hex wrench) is a hexagonal-shaped turning tool (wrench) originally manufactured by William G. Allen of the Allen Manufacturing Company in Connecticut; the question of who first patented it is debatable.

In 1744, the flat-bladed staple drill was invented, the forerunner of the first simple screwdriver. Hand screwdrivers first appeared after 1800.

Screw types

Countless types of propellers have been invented to perform specific tasks.

  • A socket head screw has an outer head, usually a hexagon, designed to be driven with a wrench or wrench.
  • Wood cords have a tapered shank that allows them to penetrate undrilled wood.
  • A machine screw has a cylindrical shaft that fits into a nut or threaded hole and a small bolt.
  • Self-tapping screws have a cylindrical shank and sharp threads that cut their own holes, and are typically used in sheet metal or plastic.
  • A drywall screw is a special purpose self-tapping screw with a cylindrical shank that has proven to be useful far beyond its original application.
  • Set screws have no heads at all and are designed to be flush with or below the surface of the workpiece.
  • A hairpin is a wood screw with two pointed ends and no head. It is used to create hidden connections between two pieces of wood.
  • Screw head shape
  • Frying pan head: a frying pan with a beveled outer edge.
  • Cheese head: disc with a cylindrical outer rim.
  • Counterborer: conical, with a flat outer surface and a beveled inner surface, which allows it to sink into the material, which is typical for wood screws.
  • Pan or pan head screws: flat inside and convex outside.
  • Mirror screw head: countersunk head with threaded hole for attaching a separate screw-on chrome cover; for attaching to a mirror.
  • Screwdriver type

    There are many tools that allow you to drive screws into the material to be fixed. Hand tools used to drive slotted and Phillips screws are called screwdrivers. A power tool that does the same job is a screwdriver. Hand tools used to drive cap bolts and other types are called wrenches (used in the UK) or spanners (used in the US).

  • Slotted screws are tightened with a flathead screwdriver.
  • A Phillips or Phillips head screw has an X-shaped slot that is actuated by a Phillips screwdriver, originally developed in the 1930s for use with power wrenches, specially made so that the screwdriver will slip or stick out under load to prevent over tightening. .
  • The Pozidriv is a modified Phillips head screw that has its own screwdriver, similar to the Phillips head, but more resistant to slippage or protrusion.
  • The hex head or hex head of a screw has a hex hole that is screwed intohex wrench, sometimes called a hex wrench, or a power tool with a hex socket.
  • Robertson drive head screws have square holes and are driven in with a special power tool socket or screwdriver (this is an inexpensive version of a household hex key).
  • A Torx screw has a slotted socket and gets a slotted screwdriver.
  • The tamper-resistant Torx socket has a lip that prevents standard Torx drivers from being inserted.
  • Nintendo uses Tri-Wing screws on their Gameboys and no drivers are installed for them, preventing even minor home repairs on these devices.
  • nuts

    A nut is a square, round, or hexagonal piece of metal with internal threads. Nuts help hold things together and are used with screws or bolts.

    Sources and additional information
  • Institute of Industrial Fasteners. "IFI Fastener Standard Book", 10th edition, Independent OH: Industrial Fastener Institute, 2018.
  • Rebchinsky, Witold. "A Good Turn: A Natural History of Screwdrivers and Screws", New York: Scribner, 2000.