A Higbee cut is a specific cut added to a screw thread to produce a blunt start, instead of the sharp end of the unmodified screw thread. It is named for its inventor Clinton Higbee. The presence of a Higbee cut on both male and female threads eliminates the chance of cross threading. A blunt start thread possessing a Higbee cut is also known as a convoluted thread.[1]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/7/70/Higbee_cut.svg/220px-Higbee_cut.svg.png)
Common Uses
editFire service
editThe Higbee cut is commonly used on fire hose couplings' threads.[2] The presence of the Higbee cut and the location of the start of the thread are often marked on couplings to assist with assembly.[3]
Thread gauges
editGauging used to inspect machine threads often includes a Higbee cut.[4]
History
editClinton Higbee invented and patented the blunt start thread in 1891.[5]
References
edit- ^ ASME B1.7-2006, Screw Threads: Nomenclature, Definitions, and Letter Symbols, The American Society of Mechanical Engineers, 2006-11-17, ISBN 0791830152
- ^ "The Higbee Thread". Fire Engineering Magazine. Vol. 1895 16, no. 13. 1895-03-30. Archived from the original on 2021-03-05. Retrieved 2021-03-04.
- ^ Wildland Fire Hose Guide. United States Department of Agriculture: Forest Service. August 1995. p. 5.
- ^ "Internal Threads". Quality Magazine. 2013-01-13. Archived from the original on 2020-11-30. Retrieved 2021-03-04.
- ^ US 447775, Clinton A. Higbee, "Screw bolt and nut", issued 1891-03-10