Shielded speaker

• US 5,406,038 A
• Filed: 01/31/1994
• Issued: 04/11/1995
• Est. Priority Date: 01/31/1994
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Reiff, David E., Branan, Mac W.
• Primary Examiner(s): WINTERCORN, RICHARD
• Application Number:
  US08/188,976
• Time in Patent Office: 435 Days
• Field of Search: 181/167, 181/168, 181/157, 381/193, 381/202
• US Class Current: 181/167
• CPC Class Codes: G06F 1/182 with special features, e.g. for use in industrial environments; grounding or shielding against radio frequency interference [RFI] or electromagnetical interference [EMI]
• CPC Class Codes: H04R 7/122 comprising a plurality of sections or layers

Abstract

Briefly, according to the invention, there is provided a shielded speaker. The speaker (10) has a diaphragm (18) coated with a metal layer (28). The coated diaphragm prevents the transmission of unwanted electromagnetic or radio frequency radiation from the front side (22) of the speaker to the rear side (24) of the speaker. In an alternate embodiment of the invention, a shielded electronic device is provided. The device consists of a housing (40) that has an opening (42) for a speaker (10) and a shielding means (44) contained within the housing. The speaker has a diaphragm coated with a metal layer. Disposed within the housing is an electronic device that is susceptible to or emits electromagnetic radiation. The electronic device (46) is coupled to the speaker and the speaker is mounted in the housing such that the metal layer is electrically coupled (48) to the shielding means. The diaphragm with the coated metal layer effectively covers the speaker opening to prevent transmission of spurious electromagnetic or radio frequency radiation through the speaker opening. In the preferred embodiment of the invention, the metal layer is a sputtered coating and is applied to one side of the diaphragm.

Claims

1. A shielded electronic device that is susceptible to electromagnetic radiation or that emits electromagnetic radiation, comprising:

a housing having a speaker opening and a shielding means;

a speaker having front and back sides and a diaphragm coated with a metal layer;

the electronic device disposed within the housing and coupled to the speaker;

the speaker mounted in the housing with the metal layer electrically coupled to the shielding means, thereby covering the speaker opening to prevent transmission of spurious electromagnetic or radio frequency radiation through the speaker opening.

2. The shielded electronic device of claim 1, wherein the metal layer is electrically coupled to the housing shielding means with a conductive polymer.

3. The shielded electronic device of claim 2, wherein the speaker diaphragm is a plastic film.

4. The shielded electronic device as described in claim 2, wherein the metal layer prevents the transmission of spurious electromagnetic or radio frequency radiation through the diaphragm.

5. The shielded electronic device of claim 2, wherein the metal layer is a sputtered metal coating.

6. The shielded electronic device of claim 2, wherein the diaphragm is coated with the metal layer on one side only.

7. A communication device, comprising:

a housing having a speaker opening and a shielding means;

a speaker having front and back sides and a diaphragm coated with a metal layer;

a radio receiver disposed within the housing and coupled to the speaker;

the speaker mounted in the housing with the metal layer electrically coupled to the shielding means, and the speaker covering the speaker opening to prevent the ingress or egress of spurious radio frequency radiation through the speaker opening.

8. The communication device of claim 7, wherein the metal layer is electrically coupled to the shielding means with a conductive polymer.

9. The communication device of claim 7, wherein the speaker diaphragm is a plastic film.

10. The communication device of claim 7, wherein the metal coating is a sputtered metal coating.

11. The communication device of claim 7, wherein the diaphragm is coated with the metal layer on one side only.

12. The communication device of claim 7, further comprising a radio transmitter disposed within the housing, the communication device thereby comprising a two-way radio.