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Hitachi Ltd
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Hitachi Ltd
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Priority to JP10596675ApriorityCriticalpatent/JPS5230476A/en
Publication of JPS5230476ApublicationCriticalpatent/JPS5230476A/en
Indicating And Signalling Devices For Elevators
(AREA)
Abstract
PURPOSE: To putputs of a plurality of ultrasonic wave receivers are added in a first-stage amplifier, whereby a number detecting apparatus which is simple in circuit configuration and can simplify signal trensmission lines is provided.