Assembly comprising an electrostatic sound generator and a transformer

Patent metadata

Field	Value
Publication number	US-2017223464-A1
Application number	US-201715419085-A
Country	US
Kind code	A1
Filing date	Jan 30, 2017
Priority date	Jan 28, 2016
Publication date	Aug 3, 2017
Grant date	—

Abstract

An assembly of a transformer and an electrostatic sound generator is especially efficient if the resonance frequency of the diaphragm is in the frequency range in which the generator is operated, such as in the interval of 1-20 kHz. Then, a smaller transformer with a winding ratio of 5000 or less may be used for feeding the sound generator, making the assembly suitable for hearing aid purposes or in-ear products such as for pro audio use.

First claim

1 . A miniature assembly comprising a transformer and a sound generator,
the sound generator comprising a housing, a diaphragm and a back plate, wherein the diaphragm divides an inner space of the housing into a first and a second volume, the back plate is positioned in one of the first and second volumes, the diaphragm has a resonance frequency in the interval of 1-14 kHz, the transformer having a first conductor and a second conductor, the second conductor being connected to the signal generator, the first conductor having a first number of windings and the second conductor having a second number of windings, where a ratio of the first number of windings to the second number of windings is lower than 1:5000.

2 . An assembly according to claim 1 , wherein the back plate is a single back plate.

3 . An assembly according to claim 2 , the sound generator further comprising a signal input and a conducting area provided on or in one of the back plate and the diaphragm, the conducting area comprising a charge, where the signal input is connected to the other of the back plate and the diaphragm.

4 . An assembly according to claim 1 , further comprising a second back plate positioned in the other of the first and second volumes, the diaphragm being positioned between the back plate and the other back plate.

5 . An assembly according to claim 4 , the sound generator further comprising a signal input, a first conducting area comprising a first charge and a second conducting area comprising a second charge, where the first conducting area is provided on or in a first of the diaphragm, the back plate and the second back plate, the signal input is connected to a second of the diaphragm, the back plate and the second back plate, and the second conductive element is provided on or in a third of the diaphragm, the back plate and the second back plate.

6 . An assembly according to claim 1 , wherein the first conductor comprises no more than 1000 windings and the second conductor has no less than 10000 windings.

7 . An assembly according to claim 1 , further comprising a low frequency sound generator, the low frequency sound generator being configured to output sound in the frequency interval of 20 Hz-10 kHz.

8 . A n assembly according to claim 7 , further comprising a medium frequency sound generator, the medium frequency sound generator being configured to output sound in the frequency interval of 200 Hz-12 kHz.

9 . An assembly according to claim 1 , further comprising a second sound generator comprising a second housing, a second diaphragm and a second back plate, wherein
the second diaphragm divides an inner space of the second housing into a third and a fourth volume, the second back plate is positioned in one of the third and fourth volumes, the second diaphragm has a resonance frequency in the interval of 1-14 kHz, the transformer having a third conductor having a third number of windings, a second ratio of the first number of windings to the third number of windings being lower than 1:5000.

10 . An assembly according to claim 9 , further comprising a third housing comprising therein the housing and the second housing and having a sound outlet.

11 . An assembly according to claim 1 , further comprising a signal emitter configured to feed a signal with a frequency in the interval of 1-20 kHz to the first conductor.

12 . A method of operating the assembly according to claim 1 , the method comprising feeding an electrical signal comprising at least a portion within the frequency interval of 1-20 kHz to the first conductor.

13 . A method according to claim 12 , wherein the sound generator housing has a portion configured to be positioned at or in an ear canal of a person, the sound generator having a sound output in the portion, the feeding step comprising:
feeding an AC signal to the first conductor and feeding a sound signal from the sound output into one end of a cylindrical cavity with a diameter of 18.55 mm and a length of 6.6 mm, the sound signal having, at the other end of the cavity, at least 80 dB/V.

14 . A personal listening device comprising the assembly according to claim 1 .

Assignees

• Sonion Nederland Bv

Inventors

• Voss Rasmus
• Van Oosten Haico
• Groffen Camiel Eugène
• De Ruijter Laurens
• Van Gilst Koen
• Blom Frederik Cornelis

Classifications

• H04R19/005

  using semiconductor materials · CPC title

• H04R2201/003

  Mems transducers or their use · CPC title

• H04R19/04

  Microphones (H04R19/01 takes precedence) · CPC title

• H04R19/013

  for loudspeakers · CPC title

• H04R3/14

  Cross-over networks · CPC title