Manual electronic keyboard

The manual electronic keyboard was the first device that generated an electrical output after the keys were depressed. The keys had a plunger mounted in a piezoelectric or piezoresistive electro-mechanical transducer housing. Its patent 3,464,531 was filed on May 16, 1967 and issued on September 2, 1969. <ref>US patent 3464531, Edward R. Herr, "Manual electronic keyboard", issued 1969-9-2, assigned to Edward M. Fletcher Jr. </ref> <ref> Manual electronic keyboard </ref>

Description

Manual electronic keyboard

• Inventor: Edward R. Herr
• Inventor: George E. Sumrall
• Patent number: 3464531
• Filing date: May 16, 1967
• Issue date: September 2, 1969

Summary

The manual electronic keyboard has a plurality of electronic keys arranged throughout the housing. Each key has a plunger mounted in a housing which contains piezoelectric or piezoresistive eletro-mechanical transducer from which a pair of terminals connects to. The plunger in each key is designed to be depressed so it bends or compresses the transducer which in turn generates an electrical signal.

Abstract

Figure 1 shows an electronic keyboard (10) attached to a mounting plate (11) and a plurality of receptacles (12) in which a plug-in sensing key is inserted in each each of the receptacles. The key (13) has a pair of contact plugs (14) (15) which makes contact with a pair of conductors (16) that as a result extend each of the receptacles (12) to an amplifier circuit (17). The amplifiers (17) are connected to a coding circuit (18) such as a diode matrix which has a number of output terminals (19) that produce a coded output on the lines (19), after the amplifiers (17) detect the operation of the key (13) mounted on the flexible cover (20).

Referenced by Patents

• US 5560724, Seiichi Iwasa & Makoto Yoshioka, "Keyboard having improved keytop", issued 1996-10-1 

• Keyboard having improved keytop

Images

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  Manual electronic keyboard

References

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