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:
Aug. 18, 2009
Filed:
Nov. 19, 2004
Detlef Plath, Meckenbeuren, DE;
Uwe Firzlaff, Uhldingen-Mühlhofen, DE;
Detlef Plath, Meckenbeuren, DE;
Uwe Firzlaff, Uhldingen-Mühlhofen, DE;
ZF Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A continuously variable transmission having an input cone pulley pair and an output cone pulley pair linked by and an encircling mechanism. One pulley of each pair is axially fixed and one pulley is axially displaceable to control the transmission ratio of the transmission. A recoil spring engages between the input moveable pulley and an axially fixed contact surface only when the transmission is in the low transmission ratio range for exerting a force to displace the input moveable cone pulley to a high transmission ratio to avoid damage to the transmission or starting clutch during towing.