Matsushita Electric Industrial Co., Ltd.

Nobuhisa Atoji

Jiro Terada

Masami Tamura

Masashi Konno

Sumio Sugawara

Kazue Sato

Hiroshi Yamamoto

Mitsuhiro Hasegawa

Satoru Ibaraki

Takashi Matsumoto

Hiroyuki Naono

Takahisa Aoi

Shoichi Kusomoto

Shoichi Kusumoto

Angular velocity sensor

The invention relates to an angular velocity sensor used in posture control of a moving element or navigation system, and is intended to realize higher sensitivity, lower offset, lower offset drift, lower translation acceleration sensitivity, and higher impact resistance in a small size and at low cost. Being made of ceramic piezoelectric material or crystal material, the constitution comprises four parallel oscillating arms 12 to 15, or 112 to 115, and a support member 11, or 111 for supporting one end of the oscillating arms or both ends commonly, in which outer two oscillating arms 12, 15, or 112, 115 of a compound tuning fork 10, or 110 in a comb shape of which position of the inside root of two oscillating arms each on inside and outside to the support member 11, or 111 in the oscillating arm direction is matched or different are used in the driving side tuning for, while inner two oscillating arms 13, 14, or 113, 114 are used in the detecting side tuning fork so as to correspond between driving and detection.

A sealed headphone having an improved sound pressure versus frequency response characteristic is disclosed. The sealed headphone comprises a mounting plate having coupling apertures, an electro-acoustic transducer attached to one side of the mounting plate and a casing covering the transducer. A space defined by the rear side of the transducer and the casing communicates via the coupling apertures with another spaced formed on the opposite side of the mounting plate so as to form an acousto-mechanical resonance circuit within the headphone. By raising the parallel resonance frequency of the resonance circuit, a higher reproduced frequency limit of the headphone is achieved.

Sealed headphone

A headphone is designed to have two resonant peaks for simulating loudspeaker reproduction. The headphone comprises a housing in which an electroacoustic transducer with a diaphragm is positioned, wherein the housing is formed with a rearward cavity positioned adjacent to the diaphragm remote from the listener's ear to provide an acoustic compliance to the generated acoustic energy. In order to generate the two resonant peaks to simulate a sensation of realism as if the listener is hearing sound from a loudspeaker, the rearward cavity is communicated with the atmosphere through apertures. The acoustic compliance of the rearward cavity coacts with the apertures to produce two resonant peaks at frequencies corresponding to the frequencies of the peaks which occur in a signal from the loudspeaker.

Headphone with two resonant peaks for simulating loudspeaker reproduction

A microphone comprises a pair of electroacoustic transducing high polymer piezoelectric semi cylindrical shaped membranes having a single axis of elongation tangent to the curvature mounted in a housing facing each other. The membranes are electrically series connected to each other with a connection between the facing surfaces thereof and are of prescribed polarizations to generate an output which is substantially twice the voltage developed individually from each membrane when said membranes are caused to flex in opposite directions and substantially zero when said membranes are caused to flex in the same direction.

Microphone capable of cancelling mechanical generated noise

A binaural sound reproducing system for transmitting sound radiated from an electro-acoustic transducer through a sound wave transmission path such as a pipe to the left and right ears of a listener includes an acoustic reverberation unit comprising a mechanical-acoustic element. The sound radiated from the electro-acoustic transducer is applied to the acoustic reverberation unit to produce indirect sound with acoustic reverberation. The indirect and direct sounds radiated from the electro-acoustic transducer are mixed and transmited through a sound wave transmission path such as the pipe to the left and right ears of the listener so that the sound image felt by the listener is localized externally of the head of the listener.

Binaural sound reproducing system with acoustic reverberation unit

Growing community of inventors

Nara, Japan

Nobuhisa Atoji