Patent · US Expired

Tactile aid to speech reception

US4250637A · kind A · utility

26Cited by
11References
17Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 13, 1979
Grant dateFeb 17, 1981
Priority date
Expiry dateJun 13, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09B21/009
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A speech signal is input to a microphone (10) and applied through a signal compressor (14) to a filter array (18) consisting of a high pass channel (20), a midfrequency channel (22) and a low pass channel (24). The outputs of the filter array (18) are precision rectified in rectifiers (28), (36) and (46). The rectified signals are applied to voltage controlled power drivers (54) and (56), where the output of the midfrequency channel (22) and the low frequency channel (24) are applied to the power driver (54) and the output of the high frequency channel (20) and the low frequency channel (24) are applied to the power driver (56). The power driver (54) drives vibrators (58) and (60) and the output of the power driver (56) drives a vibrator (62). To drive the vibrators (58) and (60), a random frequency signal at the output of a one shot multivibrator (38) is amplitude modulated by the output of the midfrequency channel (22). To drive the vibrator (62) the same random frequency signal is amplitude modulated by the output of the high pass channel (20).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.