1857
Pianoforte-Action
Smooth repetitive key action.
Henry Steinway, Jr.
1858
Pianoforte-Action
Repetition improvement upon the earlier patent.
Henry Steinway, Jr
1859
Pianoforte
Improved securing and positioning of agraffes.
Henry Steinway, Jr
1859
Grand Piano
Overstringing layout for the grand piano.
Henry Steinway, Jr
1861
Pianoforte-Action
Further improvement on repetition and hammer escape.
Henry Steinway, Jr
1861
Pianoforte-Action
Further improvement on repetition.
Henry Steinway, Jr
1862
Improvement in Piano-Forte Actions
Reworded earlier patents with additional illustrations.
Henry Steinway, Jr
1862
Improvement in Piano-Forte Actions
Further improvement on repetition and other factors.
Henry Steinway, Jr
1866
Improvement in Piano-Fortes
Introduction of a single cast-iron plate for uprights.
William Steinway
1868
Improvement in Piano-Fortes
Improvements on securing the pin-block.
C.F. Theodor Steinway
1869
Improvement in Sound-Boards for Piano-Fortes
Addition of dowels to the bridge.
C.F. Theodor Steinway
1869
Improvement in Piano-Forte Actions
Adaption of 1868 patent to grands.
C.F. Theodor Steinway
1869
Improvement in Piano-Fortes
Improvement of one piece cast-iron plate on grands.
C.F. Theodor Steinway
1871
Improvement in Piano-Actions
Improvement on key movement.
C.F. Theodor Steinway
1872
Improvement in Duplex Agraffe Scales for Piano-Fortes
Improvement of agraffe scales.
C.F. Theodor Steinway
1872
Improvement in Piano-Fortes
Improvement of plate for grands.
C.F. Theodor Steinway
1872
Improvement in Piano-Fortes
Improvement of plate for uprights.
C.F. Theodor Steinway
1873
Improvement in Piano Sounding- Boards
Reinforced soundboard.
C.F. Theodor Steinway
1874
Improvement in Piano-Forte Attachments
Addition of sostenuto mechanism.
Albert Steinway
