Speaker

Patent metadata

Field	Value
Publication number	US-11805367-B2
Application number	US-202217734319-A
Country	US
Kind code	B2
Filing date	May 2, 2022
Priority date	Mar 25, 2021
Publication date	Oct 31, 2023
Grant date	Oct 31, 2023

Abstract

A vibrating unit includes a diaphragm and a bobbin, and a voice coil is secured to the bobbin. A detecting unit includes a moving magnet and a magnetic sensor. An annular magnet support is secured to a front edge of the bobbin, and the moving magnet is positioned and secured to the magnet support. The magnetic sensor is secured to a drive supporting unit. The moving magnet is secured to the bobbin, with the magnet support therebetween. This facilitates mounting and positioning of the moving magnet.

First claim

What is claimed is:

1. A speaker comprising:
a vibrating unit including a diaphragm supported by a frame, a bobbin configured to vibrate with the diaphragm, and a voice coil disposed on the bobbin; and
a drive supporting unit including the frame and a magnetic circuit unit configured to apply a magnetic flux to the voice coil,
wherein the speaker includes a detecting unit including a moving magnet and a magnetic sensor; and
a magnet support made of a non-magnetic material is attached to the bobbin having a circular cylindrical shape, the magnet support extends along at least part of the bobbin in a circumferential direction, the moving magnet is secured to the magnet support, and the magnetic sensor is secured to the drive supporting unit.

2. The speaker according to claim 1 , wherein the magnet support has an annular shape extending along an entire circumference of the bobbin.

3. The speaker according to claim 1 , wherein a balancing mass is secured to the magnet support, the balancing mass being configured to eliminate imbalance in mass caused by securing the moving magnet to the magnet support.

4. The speaker according to claim 1 , wherein the magnet support is attached to extend along a front edge of the bobbin, the front edge being on a side of the bobbin opposite the voice coil.

5. The speaker according to claim 4 , wherein a phase plug supported by the magnetic circuit unit is provided in a region surrounded by the bobbin; and
an inner periphery of the magnet support serves as a positioning portion that determines a relative position with respect to the phase plug.

6. The speaker according to claim 1 , wherein the magnet support is secured to an outer periphery of the bobbin in a middle part of the bobbin in a front-back direction.

7. The speaker according to claim 6 , wherein a damper member is provided between the frame and the bobbin; and
the magnet support is attached to extend along a joint between the bobbin and the damper member.

8. The speaker according to claim 6 , wherein the magnet support is attached to extend along a joint between the bobbin and the diaphragm.

9. The speaker according to claim 1 , wherein the magnet support and the bobbin have a positioning structure configured to restrict relative displacement of the bobbin in the circumferential direction.

10. The speaker according to claim 1 , wherein a direction of a magnetic field applied from the magnetic circuit unit to the magnetic sensor crosses a direction of a magnetic field applied from the moving magnet to the magnetic sensor; and
a detection output based on a change in a direction of a composite vector of the two magnetic fields is obtained from the magnetic sensor.

11. A speaker comprising:
a vibrating unit including a diaphragm supported by a frame, a bobbin configured to vibrate with the diaphragm, and a voice coil disposed on the bobbin; and
a drive supporting unit including the frame and a magnetic circuit unit configured to apply a magnetic flux to the voice coil,
wherein the speaker includes a detecting unit including a moving magnet and a magnetic sensor;
a magnet support made of a non-magnetic material is attached to the bobbin having a circular cylindrical shape, the magnet support extends along at least part of the bobbin in a circumferential direction, the moving magnet is secured to the magnet support, and the magnetic sensor is secured to the drive supporting unit;
a direction of a magnetic field applied from the magnetic circuit unit to the magnetic sensor crosses a direction of a magnetic field applied from the moving magnet to the magnetic sensor; and
a detection output based on a change in a direction of a composite vector of the two magnetic fields is obtained from the magnetic sensor.

12. The speaker according to claim 11 , wherein the magnet support has an annular shape extending along an entire circumference of the bobbin.

13. The speaker according to claim 11 , wherein a balancing mass is secured to the magnet support, the balancing mass being configured to eliminate imbalance in mass caused by securing the moving magnet to the magnet support.

14. The speaker according to claim 11 , wherein the magnet support is attached to extend along a front edge of the bobbin, the front edge being on a side of the bobbin opposite the voice coil.

15. The speaker according to claim 14 , wherein a phase plug supported by the magnetic circuit unit is provided in a region surrounded by the bobbin; and
an inner periphery of the magnet support serves as a positioning portion that determines a relative position with respect to the phase plug.

16. The speaker according to claim 11 , wherein the magnet support is secured to an outer periphery of the bobbin in a middle part of the bobbin in a front-back direction.

17. The speaker according to claim 16 , wherein a damper member is provided between the frame and the bobbin; and
the magnet support is attached to extend along a joint between the bobbin and the damper member.

18. The speaker according to claim 16 , wherein the magnet support is attached to extend along a joint between the bobbin and the diaphragm.

19. The speaker according to claim 11 , wherein the magnet support and the bobbin have a positioning structure configured to restrict relative displacement of the bobbin in the circumferential direction.

Assignees

• Alps Alpine Co Ltd

Inventors

• Toita Hiroki
• Tachi Ryosuke
• Ito Ryo

Classifications

• H04R9/027 Primary

  Air gaps using a magnetic fluid · CPC title

• G01R33/072

  Constructional adaptation of the sensor to specific applications · CPC title

• H04R1/2803

  for loudspeaker transducers · CPC title

• H04R3/002

  Damping circuit arrangements for transducers, e.g. motional feedback circuits · CPC title

• H04R9/025

  Magnetic circuit · CPC title