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JPS574646A Expired / Lapsed JP ⏱️ 0.0 years remaining

Switch box system

Assignee: NEC Corp
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Filing: 1980-06-10
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Granted: —
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Expires: 2000-06-10
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Abstract

Abstract PURPOSE:To realize a use of a switch box for a blind operator, by detecting optically the on-and-off state of a lamp provided on the control face of the switch box and converting the on-and-off state into audible signals. CONSTITUTION:The on-and-off state of a lamp on the control face of a switch box is detected by a photoelectric detecting circuit PHOS containing a photodiode, a phototransistor and others and then converted into electric signals to be amplified by an amplifying circuit AMP. At the same time, the audible signals produced by an audible signal generating circuit OSC are converted into the variation of audible signals in accordance with the on-and-off state of the lamp on the control face through an audible signal control circuit ATCNT. This variation of audible signals is supplied to a telephone receiving circuit through a mixing circuit MIX and then sent to a telephone receiver R.

Inventors

  • 👤 Hideo Takahashi

Bibliographic Details

Application Number —
Jurisdiction JP
Data Source google_patents
Last Synchronized 2026-11-09 03:59
CPC Classifications
H; H04; H04M; H04M3/00; H04M3/60; H04M3/62

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Total Claims: 0
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