Index of K&E Slide Rule Patents

Patent Number	Issue Date	Subject of Invention	Inventor
219,246	Sept 02, 1879	Fuller's Calculator (Cylindrical Slide Rule)	George Fuller
249,117	Nov 01, 1881	Thacher Slide Rule	Edwin Thacher
460,930	Oct 06, 1891	Engineer's Duplex Slide Rule	William Cox
543,612	Jul 30, 1895	The Colby Stadia Slide Rule	Branch H. Colby
603,695	May 10, 1898	Triangular Frame Slide Rule	W.L.E. Keuffel
621,348	Mar 21, 1899	Dual Slide Slide Rule	W.L.E. Keuffel
651,142	Jun 05, 1900	Adjustable Mannheim Slide Rule Frame	W.L.E. Keuffel
773,235	Oct 25,1904	Watch Type Slide Rule	Elmer A. Sperry
907,373	Dec 22, 1908	Adjustable Duplex Slide Rule Frame	W.L.E. Keuffel
996,039	June 20, 1911	Magnifier for Slide Rule	W.L.E. Keuffel
1,012,660	Dec. 26, 1911	Calculating Device (watch type) assigned to Keuffel & Esser	George Lange
1,150,771	Aug. 17, 1915	The All Glass Slide Rule Runner	W.L.E. Keuffel
1,181,672	May 02, 1916	The Folded Celluloid Slide Rule Runner	W.L.E. Keuffel
1,487,805	Mar 25, 1924	Device for Making Vector Calculations	A.F. Puchstein
1,488,686	Apr 01, 1924	Log Log Duplex Slide Rule	A.W. Keuffel
1,875,927	Sept 06, 1932	Small Celluloid Slide Rule with Non-removeable Runner	A.W. Keuffel
1,904,474	Apr 18, 1933	Metal Guard for All Glass Slide Rule Runners	A.W. Keuffel
1,930,852	Oct 17, 1933	Adjustment Mechanism for Duplex Slide Rule	A.W. Keuffel
1,934,232	Nov 07, 1933	Refinement on Adjustment of the Mannheim Slide Rule	A.W. Keuffel
2,000,337	May 07, 1935	Slide Rule Case	A.W. Keuffel
2,086,502	July 06, 1937	The Metal Rimmed Improved Runner for Slide Rule	A.W. Keuffel
2,136,169	Nov 08, 1938	Slide Rule Indicator	A.W. Keuffel
2,143,559	Jan 10, 1939	Metal Reinforced Wood Slide Rule Frame	A.W. Keuffel
2,168,056	Aug 01, 1939	Slanted Lettering on Trig Scales	Carl Bernegan
2,170,144	Aug 22, 1939	The Log Log Trig Slide Rule	Lyman, Kells, et.al.
2,283,473	May 19, 1942	Special Mannheim Slide Rule (K&E Model # 4110)	John Tyler, et.al
2,285,722	Jun 09, 1942	Colored Lettering on Trig Scales	Lyman, Kells, et.al.
2,422,649	Jun 17, 1947	Rearragned Scales on Log Log Slide Rule (N4080/N4081)	James R. Bland
2,500,460	Mar 14, 1950	Range Markings on Log Log Scales	Herschel Hunt
2,534,695	Dec 19, 1950	Slide Rule Scale Placement	James R. Bland
2,602,574	Jul 08, 1952	Slide Rule Belt Carrier	Mangold & Zener