GB1493809A
(en )
1977-11-30
Push button keyboard members
GB728580A
(fr )
1900-01-01
US2091778A
(en )
1937-08-31
Keyboard construction and key control
GB1254639A
(en )
1971-11-24
Encoding keyboard
US2094883A
(en )
1937-10-05
Key control for auxiliary printing units
GB517202A
(en )
1940-01-23
Improvements in push-button switches
GB499496A
(en )
1939-01-24
Improvements relating to electric switches for use in alternating current circuits
GB121508A
(en )
1918-12-16
Improvements in or relating to Keyboards for Typewriters.
US1154355A
(en )
1915-09-21
Keyboard for computing-machines.
US2055623A
(en )
1936-09-29
Calculating machine
GB191517792A
(en )
1916-12-14
Improvements in and relating to Calculating Machines.
GB190922862A
(en )
1909-12-10
Improvements in Apparatus for Adding or Calculating.
US1094468A
(en )
1914-04-28
Adding-machine.
US1028149A
(en )
1912-06-04
Adding-machine.
GB191019976A
(en )
1911-08-24
Improvements in Cash Registers and Autographic Devices therefor.
GB190023854A
(en )
1901-03-09
Improvements in Typewriters.
SU117227A1
(ru )
1957-11-30
Многоклавишна клавиатура дл счетных машин
GB168537A
(en )
1921-09-08
Improvements relating to means for holding in close contact a movable truck and stationary cubicle of an electric switchboard or other relatively movable members
GB795089A
(en )
1958-05-14
Improvements in or relating to push-button switch assemblies for wireless sets and the like
GB694698A
(en )
1953-07-22
Improvements in or relating to a ten-key mechanism for an adding machine
GB189900449A
(en )
1899-11-25
An Improved Method of Controlling Certain of the Stops and Couplers in an Organ.
GB191019211A
(en )
1911-08-16
Improvements relating to Calculating Machines.
GB267045A
(fr )
GB199564A
(en )
1923-06-28
Improvements in press-button switches for electrical circuits
GB851509A
(en )
1960-10-19
Improvements in or relating to electric switch mechanisms