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:
Nov. 05, 2013
Filed:
Feb. 14, 2011
Alan Babb, Burnsville, MN (US);
Alan Babb, Burnsville, MN (US);
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A low frequency transducer arrangement includes at least one substantially annular magnet. A voice coil is disposed within and concentric with the magnet. A pole is disposed within and concentric with the voice coil. An air gap is defined between the magnet and the pole. The pole includes a bottom half having a downwardly facing axial recess. A plurality of first air passages extend laterally from the axial recess and fluidly interconnect the recess and the air gap. A top half has an upwardly facing axial recess. A plurality of second air passages extend laterally from the upwardly facing axial recess and fluidly interconnect the upwardly facing recess and the air gap. The first air passages and/or the second air passages are non-radially oriented.