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:
May. 28, 2013
Filed:
Dec. 03, 2008
Michael Witonis, Brighton, MA (US);
Jay Seiter, Boston, MA (US);
Morgan Misek, Jamaica Plain, MA (US);
Joshua Filgate, Boylston, MA (US);
Jesse Kuhn, Somerville, MA (US);
Michael Witonis, Brighton, MA (US);
Jay Seiter, Boston, MA (US);
Morgan Misek, Jamaica Plain, MA (US);
Joshua Filgate, Boylston, MA (US);
Jesse Kuhn, Somerville, MA (US);
Northeastern University, Boston, MA (US);
Abstract
A sequential planetary stack transmission system is provided. The system includes a stack of planetary gear sets, each gear set including a sun gear engageable with a rotatable central shaft, and freely rotatable concentrically about the central input or output shaft when not engaged with the central shaft. A plurality of planet gears engage with the sun gear, and a ring gear engages with the planet gears. The ring gears form a ring gear barrel rotatable as a unit concentrically with respect to the central shaft. A shifting assembly within the hollow central shaft engages sequentially with the sun gears to provide a desired gear ratio. The planetary stack assembly and the shifting assembly are disposed within a case. The system is suitable for a variety of applications, and is particularly suitable for bicycles.