JPS55138998A - Speaker - Google Patents

Speaker

Info

Publication number
JPS55138998A
JPS55138998A JP4704179A JP4704179A JPS55138998A JP S55138998 A JPS55138998 A JP S55138998A JP 4704179 A JP4704179 A JP 4704179A JP 4704179 A JP4704179 A JP 4704179A JP S55138998 A JPS55138998 A JP S55138998A
Authority
JP
Japan
Prior art keywords
vibration
bobbin
speaker
movement
light
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP4704179A
Other languages
Japanese (ja)
Inventor
Takafumi Ueno
Tatsuo Fukuyama
Koshin Shimada
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP4704179A priority Critical patent/JPS55138998A/en
Publication of JPS55138998A publication Critical patent/JPS55138998A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/002—Damping circuit arrangements for transducers, e.g. motional feedback circuits

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Audible-Bandwidth Dynamoelectric Transducers Other Than Pickups (AREA)
  • Circuit For Audible Band Transducer (AREA)

Abstract

PURPOSE:Not only to exactly detect vibration without being influenced by disturbance but also to make a speaker small-sized, by detecting movement of a diaphragm by use of an optical fiber, and feeding back its detecting output to the vibration part in order to conrol the vibration part. CONSTITUTION:The photodetecting end 16a of the optical fiber 16 made of glass fiber flux is located opposite to the reflecting part of a bobbin 9 which has been formed in the vibration part, and the light emitting end 16b is located opposite to the photoelectric transducer of the control circuit 17 which has been provided at the outside of the speaker frame. And movement of a diaphragm is detected by receiving at the photoreceiving end 16a the light which is the reflected light from the light source 11 in the reflecting part of the bobbin 9, the detection output from the light emitting end 16b is amplified after being converted to an electric signal by the control circuit 17, it is fed back to the voice coil 5, movement of the bobbin 9 is controlled, and vibration is detected exactly by reducing the influence of disturbance with fiber 16 and also the whole speaker is made small-sized.
JP4704179A 1979-04-16 1979-04-16 Speaker Pending JPS55138998A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4704179A JPS55138998A (en) 1979-04-16 1979-04-16 Speaker

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4704179A JPS55138998A (en) 1979-04-16 1979-04-16 Speaker

Publications (1)

Publication Number Publication Date
JPS55138998A true JPS55138998A (en) 1980-10-30

Family

ID=12764073

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4704179A Pending JPS55138998A (en) 1979-04-16 1979-04-16 Speaker

Country Status (1)

Country Link
JP (1) JPS55138998A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1569497A1 (en) * 2004-02-25 2005-08-31 Harman Becker Automotive Systems GmbH Motional feedback loudspeaker

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1569497A1 (en) * 2004-02-25 2005-08-31 Harman Becker Automotive Systems GmbH Motional feedback loudspeaker

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