Transmission structure

Abstract

[Problem] A hydromechanical continuously variable transmission capable of performing smooth switching among first to third gears in accordance with a vehicle speed is provided. [Solution] The present invention provides a gear shift output device which receives a continuously variable output in a first speed and a second speed by a planetary third element, input-side first to third transmission paths capable of transmitting driving source power to the planetary first or second element, and output-side first to third transmission paths capable of transmitting combined power from the planetary second or first element to the traveling output shaft. The first element serves as a reference power input section for inputting driving source power and the second element serves as a combined output section when a vehicle speed is a first gear in a range up to a first vehicle speed and a third gear in a rang equal to or larger than a second vehicle speed. The first element serves as the combined output section and the second element serves as the reference power input section when the vehicle speed corresponds to a second gear in a range between the first and second vehicle speeds. A rotation speed of the planetary second element is substantially the same between when an output of the gear shift output device corresponds to a second speed in the first gear and at a time of a second gear, and a rotation speed of the planetary first element is substantially the same between when an output of the gear shift output device corresponds to the second speed in the first gear and a time of a third gear.