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Current content: 157 337 350 patent documents

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1 247 852 documents amended

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EP 0209238 A3 19890308 - DOUBLE PISTON ACOUSTIC TRANSDUCER WITH SELECTABLE DIRECTIVITY

Title (en)

DOUBLE PISTON ACOUSTIC TRANSDUCER WITH SELECTABLE DIRECTIVITY

Publication

EP 0209238 A3 19890308 (EN)

Application

EP 86304398 A 19860610

Priority

US 74518485 A 19850614

Abstract (en)

[origin: EP0209238A2] A direction selective transducer which includes a center mass fixed between two active transducer element stacks and two head masses. The center mass couples the two stacks and allows the ratio of radiation produced by each head mass to be selected as desired by varying the amplitude and phase of drive voltages applied to the stacks. The transducer can also be used as a directional receiver.

IPC 1-7

H04R 17/10; B06B 1/06

IPC 8 full level

H04R 1/44 (2006.01); B06B 1/06 (2006.01); H04R 17/10 (2006.01)

CPC (source: EP)

B06B 1/0618 (2013.01)

Citation (search report)

[X] FR 2302656 A1 19760924 - FRANCE ETAT [FR]
[AD] US 3309654 A 19670314 - MILLER HARRY B

Designated contracting state (EPC)

FR GB IT

DOCDB simple family (publication)

EP 0209238 A2 19870121; EP 0209238 A3 19890308; JP S61289800 A 19861219

DOCDB simple family (application)

EP 86304398 A 19860610; JP 13638486 A 19860613