To provide a torque converter capable of reducing transmission of judder vibration generated in a sliding engaging state of a lockup clutch to a speed-change mechanism side.
In the sliding engaging state in which a clutch plate 27 of the lockup clutch 15 is in sliding contact with a front cover 11 of a converter housing 13 with a rotation difference between them, a switching valve 39 housed in a valve chamber 38 of a displacement switching mechanism 35 allows an oil chamber 2c between the clutch plate 27 and a piston 34 to be communicated with a front side space 2b because a total of the energiging force of a coil spring 40 and a force based on a lockup exhaust pressure of the front side space 2b is larger than a force based on the lockup engaging pressure of a rear side space 2a. Therefore, the piston 34 displaces forward to come into friction contact with the clutch plate 27 because a hydraulic pressure in the rear side space 2a receiving pressure at the rear surface is higher than that in the oil chamber 2c receiving pressure at the front surface, thus reducing transmission of judder vibration to the input shaft 24 side of a speed-change mechanism.
SUZUKI AKITOMO
ITO KAZUYOSHI
KUROYANAGI TAKAMITSU
NAGAI HIROKI
Makoto Onda