High-volume acoustic transducer
AssigneeWestinghouse Electric Corp.
InventorsFrancis S. McKendree, Dexter V. Wright, Peter D. Hill, Stanley S. Sattinger
Life of this patent
Estimating the term…
Abstract
A high-volume source for very low frequency applications in which conventional speakers are inadequate is disclosed. A presently preferred embodiment comprises a reservoir 32 with a pressure relief 33; a controller 34; a supply blower 36; an exhaust blower 38; a positive plenum 40; a negative plenum 42; an orifice plate with valving 44; a horn 46; and pressure transducers 48, 50, 52, 54, feeding detected pressure levels to the controller 34. An electrical command signal s(t) is also input to the controller. The command signal is a voltage analogous to the acoustic pressure or volume velocity to be output by the source.
Claims31
A high-volume acoustic transducer, comprising:
- (a) a positive plenum characterized by a positive pressure;
- (b) a negative plenum characterized by a negative pressure less than said positive pressure;
- (c) blower means coupled to said positive and negative plena for supplying a fluid to said positive plenum and withdrawing said fluid from said negative plenum, wherein said fluid comprises a member of a group consisting of:
- a gas, a mixture of gases, a mixture of combustion exhaust products, and air;
- (d) an orifice plate containing a plurality of valves for controllably releasing said fluid from said positive plenum and accepting said fluid into said negative plenum, said valves comprise a member of a group consisting of large area-modulatinq valves and on/off valves;
- and
- (e) a controller for controlling the operations of said valves in accordance with an electrical signal, wherein an acoustic signal generated by the high-volume transducer is analogous to said electrical signal, and wherein a fluid-to-fluid energy transfer takes place between said transducer and a surrounding environment.
A method for generating a high-volume acoustic signal which is analogous to an electrical signal, comprising the steps of:
- (a) maintaining the pressures (P.sub.1, P.sub.2) in first and second plena at prescribed levels, wherein said plena contain a working fluid, P.sub.1 is positive relative to a surrounding atmospheric pressure, and P.sub.2 is negative relative to the surrounding atmospheric pressure;
- and
- (b) generating a high-volume acoustic signal by controllably releasing said fluid from said positive plenum through a first set of valves and accepting said fluid into said negative plenum through a second set of valves;
- wherein said fluid comprises a member of a group consisting of:
- a gas, a mixture of gases, a mixture of combustion exhaust products, and air;
- said valves comprise a member of a group consisting of large area-modulating valves and on/off valves, and wherein a fluid-to-fluid energy transfer takes place between said transducer and a surrounding environment.
A system for generating a high-volume acoustic signal which is analogous to an electrical signal, comprising:
- (a) means for maintaining the pressures (P.sub.1, P.sub.2) in first and second plena at prescribed levels, wherein said plena contain a working fluid, P.sub.1 is positive relative to a surrounding atmospheric pressure, and P.sub.2 is negative relative to the surrounding atmospheric pressure;
- and
- (b) means for generating a high-volume acoustic signal by controllably releasing said fluid from said positive plenum through a first set of valves and accepting said fluid into said negative plenum through a second set of valves;
- wherein said fluid comprises a member of a group consisting of:
- a gas, a mixture of gases, a mixture of combustion exhaust products, and air;
- said valves comprise a member of a group consisting of large area-modulating valves and on/off valves, and wherein a fluid-to-fluid energy transfer takes place between said transducer and a surrounding environment.
A high-volume acoustic transducer, comprising:
- (a) a positive pressure plenum characterized by positive pressure;
- (b) blower means coupled to said plenum for supplying fluid to said plenum, wherein said fluid comprises a member of a group consisting of:
- a gas, a mixture of gases, a mixture of combustion exhaust products, and air;
- (c) an orifice plate containing a plurality of on-off valves for controllably releasing said fluid from said plenum;
- and
- (d) a controller for controlling the operation of said valves in accordance with an electrical signal, wherein an acoustic signal generated by the high-volume transducer is analogous to said electrical signal, wherein a fluid-to-fluid energy transfer takes place between said transducer and a surrounding environment.
Dependencies are inferred from the claim text.