Robertson screw
![](https://upload.wikimedia.org/wikipedia/commons/thumb/f/fe/Robertson_screw.jpg/170px-Robertson_screw.jpg)
The Robertson screw is a screw with a square internal square head . It has always been rare in Europe, and is still common in Canada and the United States .
The output of the screwdriver is an external square. Similar to keys for hexagon socket , Robertson screwdrivers are also available with angled screwdriver blade.
The Robertson drive is named after its inventor, the Canadian Peter L. Robertson , who invented these screws and the appropriate screwdrivers in 1908 and applied for a patent. The inner square enables a good frictional connection and the screwdriver, unlike screws with a slot , does not slip out of the screw head as easily. Thus this system was more suitable for industrial use.
This also convinced the Ford Motor Company, one of Peter L. Robertson's first customers. In the Ford Model T -bolts Robertson were used on 700th
See also
Web links
- Robertson Inc. - Robertson Company website