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:
Apr. 04, 1989
Filed:
Nov. 16, 1987
Hans-Jurgen Dach, Friedrichshafen, DE;
Anton Ott, Tettnang, DE;
Zahnradfabrik Friedrichshafen AG, Friedrichshafen, DE;
Abstract
A planet wheel speed change transmission for motor vehicles arrayed in groups with one basic drive and one group drive associated therewith in series, where the basic drive consists of a speed change transmission with fixedly coupled partial drive and a sequence of gear ratios decreasing in principle from first to highest gear, and the group drive is shifted only once during the entire shift sequence and the number of gears in the basic drive is increased by a single gear, with shift clutches, brakes and free-wheel mechanisms for the automatic shifting of at least four forward speeds, where the shifting of the group drive occurs between two of the gears of the basic drive, or where the group drive is speed-reducing and then shifting occurs also ahead of the first gear of the basic drive and the transmission ratio of the group drive, when it is shifted, is created in dependence upon the gear ratios in the adjacent gears of the basic drive.