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:
Jul. 15, 2014
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 a substantially cylindrical structure surrounding a pole piece. The pole piece and the substantially cylindrical structure define a substantially cylindrical air gap therebetween. Two opposite ends of the air gap are both open and separated from each other in an axial direction. A first magnet is disposed in either the pole piece or the substantially cylindrical structure. A second magnet is separated in the axial direction from the first magnet by a middle magnetic gap. The second magnet is disposed in either the pole piece or the substantially cylindrical structure. The first and second magnets provide flux in a same direction in the middle magnetic gap. A top magnetic gap is disposed axially adjacent the first magnet and opposite the middle magnetic gap. A bottom magnetic gap is disposed axially adjacent the second magnet and opposite the middle magnetic gap. A voice coil is at least partially disposed in the air gap and operates in the middle magnetic gap.