Electric-mechanical-acoustic-transducer and portable communication device including the same

• US 20030022702A1
• Filed: 07/23/2002
• Published: 01/30/2003
• Est. Priority Date: 07/25/2001
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Saiki, Shuji, Usuki, Sawako
• Granted Patent: US 7,194,287 B2
• Time in Patent Office: Days
• US Class Current: 455/567
• CPC Class Codes: H04R 11/06 Telephone receivers
• CPC Class Codes: H04R 2400/03 Transducers capable of generating both sound as well as tactile vibration, e.g. as used in cellular phones

Abstract

An electric-mechanical-acoustic-transducer includes a diaphragm; a movable section; a driving section for generating a driving force for vibrating the diaphragm and the movable section; and a suppression section for suppressing a sharpness (Q factor) of a vibration force obtained by the vibration of the movable section.

Claims

1. An electric-mechanical-acoustic-transducer, comprising:

a diaphragm;

a movable section;

a driving section for generating a driving force for vibrating the diaphragm and the movable section; and

a suppression section for suppressing a sharpness (Q factor) of a vibration force obtained by the vibration of the movable section.

2. An electric-mechanical-acoustic-transducer according to claim 1, wherein the movable section includes a magnetic circuit for supplying a magnetic flux to the driving section.

3. An electric-mechanical-acoustic-transducer according to claim 2, wherein the movable section further includes a weight integrated with the magnetic circuit.

4. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the movable section is provided so as to face the diaphragm, and

the suppression section is an elastic member provided oppositely to the diaphragm with respect to the movable section.

5. An electric-mechanical-acoustic-transducer according to claim 4, wherein the elastic member is a sponge.

6. An electric-mechanical-acoustic-transducer according to claim 4, wherein the elastic member is a spring.

7. An electric-mechanical-acoustic-transducer according to claim 1, further comprising a supporting section for supporting the diaphragm, wherein the suppression section includes:

a first magnet provided oppositely to the diaphragm with respect to the movable section which faces the diaphragm, and

a second magnet provided in contact with the supporting section so as to face the first magnet and magnetized oppositely to the first magnet.

8. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the suppression section is a suspension for supporting the movable section, and

the suspension is formed of a material having an internal loss coefficient equal to or greater than 0.01.

9. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the suppression section is a suspension for supporting the movable section, and

the suspension is formed of a composite material containing a polymeric material having a high viscosity.

10. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the suppression section is a suspension for supporting the movable section, and

the suspension is formed of a dislocation-type vibration damping alloy.

11. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the suppression section is a suspension for supporting the movable section, and

the suspension is formed of a laminate material containing at least two materials having different internal loss coefficients layered on each other.

12. An electric-mechanical-acoustic-transducer according to claim 11, wherein the suspension is formed of a damping steel plate formed of a laminate material containing a metal and a resin layered on each other.

13. An electric-mechanical-acoustic-transducer according to claim 11, wherein the suspension is formed of a vibration damping alloy which is a laminate material containing at least two metals layered on each other.

14. An electric-mechanical-acoustic-transducer according to claim 1, wherein:

the electric-mechanical-acoustic-transducer further comprises a supporting section for supporting the diaphragm,

the supporting section and the diaphragm have a space therebetween,

the electric-mechanical-acoustic-transducer further comprises a dividing section, coupled to the movable section and the supporting section, for dividing the space into two,

the supporting section has at least one air hole for communicating a space between the dividing section and the supporting section to an outside of the electric-mechanical-acoustic-transducer, and

the suppression section includes the dividing section, the supporting section and the at least one air hole.

15. A portable communication device, comprising:

a housing; and

an electric-mechanical-acoustic-transducer provided in the housing,

wherein;

the electric-mechanical-acoustic-transducer includes a diaphragm, a movable section, a driving section for generating a driving force for vibrating the diaphragm and the movable section, and a suppression section for suppressing a sharpness (Q factor) of a vibration force obtained by the vibration of the movable section, and

the housing has a sound hole for releasing a sound generated by the electric-mechanical-acoustic-transducer.