×

Microphone

  • US 4,850,016 A
  • Filed: 01/29/1988
  • Issued: 07/18/1989
  • Est. Priority Date: 01/29/1987
  • Status: Expired due to Fees
First Claim
Patent Images

1. A noise cancelling microphone for location inside a hollow microphone-containing portion of a telephone handset at an internal surface of an apertured wall of said containing portion, the whole of the outer surface of said wall being presented towards the mouth of the user when the handset is in use, said microphone comprising:

  • a housing having an open face adapted to be secured in contact with the internal surface of said apertured wall of the handset, said housing including an imperforate rear wall and imperforate side walls extending between said open face and said imperforate rear wall;

    tubular means formed within said housing to define a cavity extending at one end from said internal surface of said apertured wall to an open end of said tubular means within said housing, said open end of said tubular means being spaced from said imperforate side walls and from the imperforate rear wall of said housing;

    a diaphragm secured at its periphery inside said cavity for location substantially parallel to said internal surface of said apertured wall;

    said cavity being defined for location in relation to a first opening in a central region of said apertured wall to provide a first sound path to a front surface of said diaphragm; and

    a second opening in said apertured wall outside said tubular means to provide a second sound path, separate from said first sound path, which extends between said tubular means and the imperforate side walls of said housing to the open end of said tubular means and thence to a rear surface of said diaphragm;

    whereby, when the microphone is mounted in place, at least one opening in said apertured wall provides access to said front surface of said diaphragm and at least one further opening in said apertured wall provides access to said rear surface of said diaphragm.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×