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Encyclopedia > Robertson screwdriver
Robertson screwdrivers
Robertson screwdrivers

A Robertson screwdriver is a type of screwdriver with a square-shaped tip with a slight taper (in the same way that flatheads, Phillips, Allen, and Torx have flat, ×-shaped, hexagonal, and hexagrammal tips, respectively). Image File history File linksMetadata Download high resolution version (1024x866, 82 KB) Picture of four Robertson screwdrivers (square bits) taken 16 October 2005 by Luigi Zanasi (myself) on my workbench using a Olympus digital camera. ... Image File history File linksMetadata Download high resolution version (1024x866, 82 KB) Picture of four Robertson screwdrivers (square bits) taken 16 October 2005 by Luigi Zanasi (myself) on my workbench using a Olympus digital camera. ... A basic screwdriver (slotted tip shown) A screwdriver is a device specifically designed to insert and tighten, or to loosen and remove, screws. ... In plane (Euclidean) geometry, a square is a polygon with four equal sides, four right angles, and parallel opposite sides. ... Phillips Head refers to the shape of the head of the screw as a plus sign. ... Allen keys of various sizes An Allen wrench, Allen key, hex key or hex head wrench is a tool used to drive Allen screws and bolts, which have a hexagonal socket in the head. ... TORX screw head design TORX, developed by Textron Fastening Systems (formerly Camcar Textron), is the trademark for a type of screw head characterized by a 6-point star-shaped pattern (in the same way that slotted heads, Phillips, Allen, and Robertson have flat, ×-shaped, hexagonal, and square tips, respectively). ... A regular hexagon In geometry, a hexagon is a polygon with six edges and six vertices. ... A hexagram (also known as sexagram or a magicians/sorcerers star) is a six-pointed star, a type of complex star polygon. ...

Robertson compared with other screws: (a) Slotted, (b) Phillips, (c) Pozidriv, (d) Torx, (e) Allen key, (f) Robertson, (g) Tri-Wing, (h) Torq-Set, (i) Spanner Head
Robertson compared with other screws:
(a) Slotted, (b) Phillips, (c) Pozidriv, (d) Torx, (e) Allen key, (f) Robertson, (g) Tri-Wing, (h) Torq-Set, (i) Spanner Head

Canadian P.L. Robertson invented the Robertson screw and screwdriver in 1908. He received a patent in 1909, and later applied for and received other patents. The last patent expired in 1964. Diagram of several different kinds of screw drive. ... Diagram of several different kinds of screw drive. ... Phillips Head refers to the shape of the head of the screw as a plus sign. ... The Pozidriv screw type is patented, similar to cross-head but designed not to slip, or cam out. ... TORX screw head design TORX, developed by Textron Fastening Systems (formerly Camcar Textron), is the trademark for a type of screw head characterized by a 6-point star-shaped pattern (in the same way that slotted heads, Phillips, Allen, and Robertson have flat, ×-shaped, hexagonal, and square tips, respectively). ... Allen keys of various sizes An Allen wrench, Allen key, hex key or hex head wrench is a tool used to drive Allen screws and bolts, which have a hexagonal socket in the head. ... Peter Lymburner Robertson (1879-1951) invented the square-drive screw, first produced in his Milton factory in 1908. ... Screws come in a variety of shapes and sizes for different purposes. ... 1908 (MCMVIII) was a leap year starting on Wednesday (link will take you to calendar). ... A patent is a set of exclusive rights granted by a state to a person for a fixed period of time in exchange for the regulated, public disclosure of certain details of a device, method, process or composition of matter (substance) (known as an invention) which is new, inventive, and... 1909 (MCMIX) was a common year starting on Friday (see link for calendar). ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ...


The drivers are famous for holding onto screws (you can start driving a screw horizontally into the wall, and leave the screwdriver in the screw while you have lunch), and allow for things like an angled screw driver and trim head screws. The references in this article would be clearer with a different and/or consistent style of citation, footnoting or external linking. ...


Robertson screwdrivers have a colour-coded handle for easy selection as different screw sizes require different size tips. The colours and their associated screw sizes are:

  • Orange (#00) — No. 1 & 2 screws (uncommon)
  • Yellow (#0) — No. 3 & 4 screws
  • Green (#1) — No. 5, 6 & 7 screws
  • Red (#2) — No. 8, 9 & 10 screws
  • Black (#3) — No. 12 and larger screws

Robertson had licensed the screw in England but the party with which he was dealing intentionally put the company under and purchased the rights from the trustee thus circumventing Robertson. He spent a small fortune buying back the rights. After that he refused to ever allow anyone to make the screws under license. When Henry Ford tried out the Robertson screws he found they saved considerable time in the production of cars but when Robertson refused to license the screws to Ford, he realised that the use of the screws would not be guaranteed and stopped using them. This largely explains why they never became established in the United States, despite being superior. This article or section does not cite its references or sources. ... A company is, in general, any group of persons, which are known as its members, united to pursue a common interest. ... Henry Ford (1919) Henry Ford (July 30, 1863 – April 7, 1947) was the founder of the Ford Motor Company and father of modern assembly lines used in mass production. ... This article or section does not cite its references or sources. ...


Today Robertson screws are almost unknown in the United Kingdom, scarce in the United States, where they are used mainly in theatrical set construction and account for 10% of screws sold, while being very common in Canada where 85% of the screws sold use the Robertson head.


See also


 
 

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