Abstract: The invention is a low frequency ported loudspeaker system comprising a hollow rectangular enclosure, the enclosure having a woofer driver airtight mounted to an aperature of the enclosure, changes in air pressure of the invention's enclosure's interior air mass are reduced by the coaction of a liquid mass contained within an open-ended manometer type structure, inlet of open-ended manometer type structure being attached to the enclosure and is in pressure conveyance with the invention's interior air mass.
Abstract: A hydrostatic speaker includes an oscillator, a partition diaphragm disposed in the oscillator to divide the oscillator into two chambers, at least one of which chambers serves as a fluid chamber to cause the partition diaphragm to vibrate in response to external signals from a source, an acoustic sound radiation core connected with the partition diaphragm via a rod, a sensor for detecting fluid pressure in the fluid chamber and another sensor for detecting a movement of the partition diaphragm. The hydrostatic speaker is provided with a speaker driver which includes a fuild pressure controller connected to a pressure source for controlling the fluid pressure in the fluid chamber, and a control amplifier for controlling the fluid pressure controller in accordance with the external signals.
Type:
Grant
Filed:
June 5, 1989
Date of Patent:
October 22, 1991
Assignee:
Ishikawajima-Harima Heavy Industries Co., Ltd.
Abstract: A pneumatic loudspeaker with a continuous pressurized fluid flow modulated by an obstacle forming an integral part of a moving armature with an electromagnetic coil supported by a leakproof elastic membrane. The moving armature comprises a cylindrical support and a winding housed in a flat groove made in the body of the support, the winding and its support forming a rigid integral assembly, the winding being sandwiched between a first layer of glue coating the bottom of the flat groove and a second layer of the glue submerging the turns of the winding and endowing the assembly with a smooth and uniform surface.
Type:
Grant
Filed:
March 20, 1989
Date of Patent:
October 1, 1991
Assignee:
Bertin & CIE
Inventors:
Jean Julia, Ferdinand Pollet, Jean-Francois Foissey
Abstract: An acoustic detection device having a parabolic dish antenna for gathering ound waves and providing a first stage of amplification, an exponential horn located at the focus of the parabolic dish antenna for further acoustic amplification, a fluidic gainblock for a final stage of amplification, and acoustic earphones for listening. Either a hand operated latex bulb or a mechanical pump is used to pressurize a plastic fluid storage container that is used to supply fluid to the fluidic gainblock. Within the fluidic gainblock are four or more staged laminar proportional amplifiers having a bandwidth of 0 to 4,000 Hz.
Type:
Grant
Filed:
December 1, 1989
Date of Patent:
October 16, 1990
Assignee:
The United States of America as Represented by the Secretary of the Army
Abstract: An electrical blower is used to pass cooling air through a loudspeaker driver. The blower is connected in parallel to the leads between the amplifier and speaker such that the blower speed and cooling increases with increased power consumption and heat generation by the driver.