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. 28, 1981
Filed:
Jan. 19, 1979
Kenneth B Harmon, Carmel, IN (US);
General Motors Corporation, Detroit, MI (US);
Abstract
A transmission having a torque converter, lockup clutch, and a 5-speed planetary transmission having four planetary gearsets and six frictiondrive-establishing devices combined to provide five forward speed range drives having a large total gear ratio step, and a reverse drive having a moderate and a high gear ratio. The 1st or primary gearset, with the primary input to the sun gear, the ring gear braked, and carrier output, provides 1st range drive having the largest torque multiplication gear ratio. The 2nd, 3rd and 4th gearsets, the secondary gearsets, are used to provide a secondary input having decreasing torque multiplication gear ratios, to the ring gear of the 1st gearset which, with the primary input to the sun gear, provides 2nd through 5th range drives having decreasing gear ratios. The gear ratio steps between 1st, 2nd, and 3rd ranges are wide, and between 3rd, 4th, and 5th ranges are very close. The automatic controls provide torque converter drive in a portion or all of 1st and 2nd range drives and in a portion of 3rd range drive up to a transition output speed, and lockup drive above the transition output speed in 3rd range drive and all of 4th and 5th range drives, to maintain engine speed within a small engine working speed range between the peak torque speed and maximum governed speed.