Infinitely variable transmission
AssigneeNissan Motor Co., Ltd.
InventorHirofumi Shimizu
Life of this patent
Estimating the term…
Abstract
In an infinitely variable transmission (IVT) for use with a vehicle, an output gear (3B) of a fixed speed ratio transmission (3) is joined to a planet carrier (5B) of a planetary gear set (5), and a gear (4A) which outputs the rotation of a continuously variable transmission (2) is joined to a sun gear (5A) of the planetary gear set (5). A ring gear (5C) of the planetary gear set (5) is joined to an IVT output gear (7) via a final output shaft (6). The gears are made of helical gears, and the tooth trace directions of the gears are set so that when a torque for driving the vehicle forward is transmitted from the engine to the drive shaft (11), the thrust force acting on the IVT output gear (7) is opposite to the thrust force acting on the ring gear (5C).
Claims12
An infinitely variable transmission interposed between an engine and a drive shaft of a vehicle to transmit an engine torque to the drive shaft, comprising:
- a first shaft joined to the engine;
- a second shaft disposed parallel to the first shaft;
- a fixed speed ratio transmission comprising a first rotation element supported on the second shaft which outputs the rotation of the first shaft at a fixed speed ratio;
- a continuously variable transmission comprising a second rotation element supported on the second shaft which outputs the rotation of the first shaft at an arbitrary speed ratio, the first rotation element and second rotation element being supported free to rotate relative to each other;
- a planetary gear set disposed between the first rotation element and the second rotation element, the planetary gear set comprising a sun gear comprising a helical gear joined to the second rotation element, a planet carrier joined to the first rotation element and a ring gear which comprises a helical gear varying a rotation direction and a rotation speed according to a rotation speed difference between the sun gear and the planet carrier, the planet carrier supporting a planet gear comprising a helical gear meshed with the sun gear and the ring gear, and revolving around the sun gear together with the planet carrier;
- a final output gear comprising a helical gear joined to the ring gear and disposed between the planetary gear set and second rotation element;
- and
- a transmitting gear comprising a helical gear which meshes with the final output gear and transmits a rotation of the final output gear to the drive shaft,
- wherein the ring gear and the final output gear have tooth traces with which, when a torque is transmitted from the engine to the drive shaft, a thrust force exerted by the planet gear on the ring gear and a thrust force exerted by the transmitting gear on the final output gear act in opposite directions.
Dependencies are inferred from the claim text.