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US 7,252,608 B2Granted
Automatic transmission having at least two conical disk sets
AssigneeZF Friedrichshafen AG
InventorsMatthias Reisch, Olrik Weinmann, Bernhard Sich, Michael Ebenhoch
Life of this patent
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Abstract
An automatic transmission (1) is described, having a variator (5) that comprises at least two conical disk sets (2, 3), such that a wrap-around element (4) is guided via the conical disk sets (2, 3) for torque transmission with continuous variation of the transmission ratio. In this, the arrangement of the rotation axes of two conical disks of at least one conical disk set relative to one another can be varied.
Claims10
An automatic transmission with a variator, the transmission comprising:
- a belt coupled between first and second conical disks of a first disk set and first and second conical disks of a second disk set for torque transfer between the first and the second disk sets;
- wherein a continuously variable transmission ratio is determined by a ratio between a first radius of the belt, at the first disk set, and a second radius of the belt, at the second disk set;
- the first one of the conical disks of the first disk set being rotatable and axially fixed and tiltable on a shaft (7) and the second one of the conical disks of the first disk set being rotatable and axially moveable along the shaft;
- a tilt actuator acting on the first conical disks of the first disk set for varying a tilt angle between rotation axes of the first and the second conical disks, whereby
- a variation of the tilt angle between the axes of rotation of the first and the second conical disks of the first disk set causes the first radius of the belt, at the first disk set, and the second radius of the belt, at the second disk set, to one of increase and decrease along a generally spiral path from a first transmission ratio to a second transmission ratio;
- the first conical disk only tilts after achieving a certain contact pressure force between the first conical disk and the belt;
- and
- the rotatable and axially fixed and tiltable connection between the first conical disk and the shaft is elastic and the tilt actuator acts upon a bearing that supports the first conical disk to tilt the first conical disk relative to the second conical disk.
5 more elements
Dependencies are inferred from the claim text.