JPS558185A - Monaural both-ear hearing device - Google Patents

Abstract

PURPOSE:To set normally the acoustic image outside the head of the hearer by installing the opening part, the timbal stretched out with in the chamber, the spring and the thin film blocking the hole on the partition wall each into the cylindrical case which is partitioned into two chambers with the partition wall. CONSTITUTION:Speaker 3 is attached to case 2, and the sound wave sent from the speaker is transmitted to ear fitting tool 19 and 20 via the tube. Cylindrical case 8 is partitioned into two chambers A and B via partition wall 10, and timbal 9 and 12 are stretched out at the opening part and the chambers with hole 11 on wall 10 blocked with thin film 18. Timbal 9 vibrates by the sound wave radiated from speaker 3, and the vibration is transmitted to spring 13 in the form of the mechanical vibration to radiate the sound wave before and after timbal 9. This sound wave is changed into the indirect sound which is delayed more by the fixed time than the direct sound radiated through the speaker and then radiated into chamber B1 and B2. Thus, the direct and indirect sounds are transmitted to the right and left ears of the hearer via branch tube 15 and 17 plus tool 19 and 20, and accordingly the acoustic image is recognized outside the hearer's head. In this case, film 18 prevents both the mixture of the direct sound and the reverse current of the indirect sound, thus avoiding impairment of the acoustic image's normal setting outside the head.