Patent ID: 6077185
Filing Date: 2000-06-20
Classification: F16H

Abstract:
A toroidal continuously variable transmission comprising:first and second toroidal speed change units disposed coaxially upon a main shaft, the first toroidal speed change unit having first and second power rollers sandwiched between a first input cone disk and a first output cone disk, which first disks are collinearly arranged, and the second toroidal speed change unit having third and fourth power rollers sandwiched between a second input cone disk and a second output cone disk, which second disks are collinearly arranged, the first and second input and output cone disks being collinear on a same axis of rotation;a first piston that drives the first power roller in a direction perpendicular to the rotation axis to change a gyration angle thereof;a second piston that drives the second power roller in a direction perpendicular to the rotation axis to change a gyration angle thereof;a third piston that drives the third power roller in a direction perpendicular to the rotation axis to change a gyration angle thereof;a fourth piston that drives the fourth power roller in a direction perpendicular to the rotation axis to change a gyration angle thereof;first and second opposing hydraulic chambers sandwiching the first piston to drive the first piston in mutually opposite directions;third and fourth opposing hydraulic chambers sandwiching the third piston to drive the third piston in mutually opposite directions;at least one chamber that drives each of the second and fourth pistons;a speed change control valve that supplies hydraulic fluid to the hydraulic chambers of the first, second, third, and fourth pistons;hydraulic fluid conduits connecting the first, second, third, and fourth chambers, and the chambers for the second and fourth pistons to the speed change control valve, the hydraulic fluid conduits including first, second, third, and fourth fluid conduits communicating respectively with the first, second, third, and fourth hydraulic chambers, wherein the first and third chambers fluidly communicate with each other through the first and third fluid conduits, and the second and fourth chambers fluidly communicate with each other through the second and fourth fluid conduits; anda damping element comprising an orifice provided in one of the first and second fluid conduits, and one of the third and fourth fluid conduits to provide resistance to a stroke thereof in response to an external disturbance.