The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 04, 1977
Filed:
Sep. 19, 1975
Robert L Propst, Ann Arbor, MI (US);
Michael A Wodka, Ypsilanti, MI (US);
Herman Miller, Inc., Zeeland, MI (US);
Abstract
Masking sound generating apparatus for use in a conventional room enclosure occupied by adult persons of average range of heights comprising a hollow enclosure having a top opening and a side opening, a speaker mounted inside the enclosure intermediate the top opening and the side opening and facing outwardly from the apparatus through the top opening, and a circuit in the enclosure operable to develop an electric signal which is converted to an audible sound signal emitted by the speaker. Modulation means are incorporated into the circuit to cyclically vary the amplitude of the sound signal which provides the masking sound signal with a pleasant, natural sound characteristic. The sound generating apparatus is located in the room at a height intermediate the head of a standing adult person and the ceiling, and is positioned so that the speaker faces in an upwardly direction to direct sound signals toward the ceiling. Other sound signals produced by the speaker eminate from the side opening to provide the masking sound with a slight undertone characteristic.