Patent ID: 6679132
Filing Date: 2004-01-20
Classification: F16H,Y10T

Abstract:
A transmission comprising:a first shaft directly connected to a torque source to receive an output torque; a first rotational member coaxially provided with respect to the first shaft and unitarily rotatable with the first shaft; a first gear coaxially provided with respect to the first shaft and rotatable relative to the first shaft; a first clutch mechanism for engaging and disengaging the first rotational member and the first gear; a second rotational member coaxially provided with respect to the first shaft and unitarily rotatable with the first shaft; a second gear coaxially provided with respect to the first shaft and rotatable relative to the first shaft; a second shaft for engaging with the second gear; a second clutch mechanism for engaging and disengaging the second rotational member and the second gear; a gear member having a first gear portion and a second gear portion for effecting gear shifting; the first gear portion being engaged with the first gear; the second gear portion being engaged with the second shaft; at least one of the first gear and the second gear being positioned between the first rotational member and the second rotational member; the first clutch mechanism comprising a first piston axially movable relative to the first rotational member, a plurality of first rotational member friction plates fixed to the first rotational member and a plurality of first gear friction plates fixed to the first gear, the second clutch mechanism comprising a second piston axially movable relative to the second rotational member, a plurality of second rotational member friction plates fixed to the second rotational member and a plurality of second gear friction plates fixed to the second gear; the first piston being axially moved in accordance with hydraulic pressure supplied between the first rotational member and the first piston for engaging the first rotational member friction plates and the first gear friction plates, and the second piston being axially moved in accordance with hydraulic pressure supplied between the second rotational member and the second piston for engaging the second rotational member friction plates and the second gear friction plates; and wherein a moving direction of the first piston to engage the first rotational member friction plates with the first gear friction plates is the same as a moving direction of the second piston to engage the second rotational member friction plates and the second gear friction plates.