GB779476A - Improvements in or relating to sound reproducing devices and the manufacture thereof - Google Patents

Improvements in or relating to sound reproducing devices and the manufacture thereof

Info

Publication number
GB779476A
GB779476A GB2365355A GB2365355A GB779476A GB 779476 A GB779476 A GB 779476A GB 2365355 A GB2365355 A GB 2365355A GB 2365355 A GB2365355 A GB 2365355A GB 779476 A GB779476 A GB 779476A
Authority
GB
United Kingdom
Prior art keywords
piece
pole
spool
permanent magnets
coil
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.)
Expired
Application number
GB2365355A
Inventor
Huw Bryant Edwards
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.)
Ericsson Telephones Ltd
Original Assignee
Ericsson Telephones 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 Ericsson Telephones Ltd filed Critical Ericsson Telephones Ltd
Publication of GB779476A publication Critical patent/GB779476A/en
Expired 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
    • H04R11/00—Transducers of moving-armature or moving-core type
    • H04R11/02—Loudspeakers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R11/00—Transducers of moving-armature or moving-core type
    • H04R11/06—Telephone receivers

Abstract

779,476. Instruments for deaf persons. ERICSSON TELEPHONES, Ltd. Aug. 17, 1955, No. 23653/55. Class 40 (4). In an electromagnetic transducer having an armature 1 spot-welded to a magnetic acoustic diaphragm 2, a non-magnetic bush 4 soldered to the stem of polepiece 3 carries an annular pole-piece 5 to form with the base of pole-piece 3 a spool for the actuating coil and a pair of cheeks between which permanent magnets 6 are housed. An insulated block 8 carrying conductor sockets 7 is fastened into the base of pole-piece 3 and the permanent magnets which are magnetized through their depth terminate on each side of the block. Arcuate permanent magnets are shown but a number of bar magnets or a horse-shoe magnet may alternatively be used. The diaphragm is controlled by a minute hole in the annular pole-piece which connects with the air space around the sockets 7. The use of a jig in connection with the assembly is described and the coil 9 may be insulated from the spool either by the immersion of the spool in varnish before the coil is wound; or by the insulation of the stem and inner faces of the cheeks with waxed paper. The top end of cylindrical cover 10 is spun over the rim of earpiece 11 the centre of which is tapered to carry an ear plug. The instrument is stated to be sufficiently small to fit into the ear and numerous dimensions are given.
GB2365355A 1962-03-14 1955-08-17 Improvements in or relating to sound reproducing devices and the manufacture thereof Expired GB779476A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB973462A GB932276A (en) 1962-03-14 1962-03-14 Electro-acoustic transducers

Publications (1)

Publication Number Publication Date
GB779476A true GB779476A (en) 1957-07-24

Family

ID=9877738

Family Applications (2)

Application Number Title Priority Date Filing Date
GB2365355A Expired GB779476A (en) 1962-03-14 1955-08-17 Improvements in or relating to sound reproducing devices and the manufacture thereof
GB973462A Expired GB932276A (en) 1962-03-14 1962-03-14 Electro-acoustic transducers

Family Applications After (1)

Application Number Title Priority Date Filing Date
GB973462A Expired GB932276A (en) 1962-03-14 1962-03-14 Electro-acoustic transducers

Country Status (2)

Country Link
GB (2) GB779476A (en)
MY (1) MY6400093A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7106490A (en) * 1971-05-12 1972-11-14

Also Published As

Publication number Publication date
GB932276A (en) 1963-07-24
MY6400093A (en) 1964-12-31

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