Four speed ratio automatic power transmission.

摘要

A multiple speed transmission for an automotive vehicle includes three simple planetary gear units (16, 18, 20) and clutches and brakes applied and released selectively to produce four forward speed ratios and reverse drive. Two of the gear units produce three of the four drive torque delivery paths and the reverse drive torque delivery path. A third gear unit, located between a torque converter (26) and the first and second gear units, produces an overdrive speed ratio. A coast clutch (72) is engaged to produce an engine braking effect in each of three manually selected speeds; an overdrive brake (74) produces engine braking in the fourth speed automatic range.