CVT transmission

Patent metadata

Field	Value
Publication number	US-10295030-B2
Application number	US-201415101909-A
Country	US
Kind code	B2
Filing date	Nov 28, 2014
Priority date	Dec 9, 2013
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A CVT transmission having an input drive, a continuously variable variator, a sub-transmission to achieve at least two operating ranges (low and high) each with continuously variable gear ratios, and having a direct-shift stage for switching between a first operating range (low) and a second operating range (high) with continuously variable gear ratios. For the first operating range (low) the sub-transmission includes a non-positive clutch, such as a friction clutch, and for the second operating range (high) it includes a positive clutch, such s a jaw clutch.

First claim

What is claimed is:

1. A CVT transmission comprising:
an input drive;
a continuously variable variator; and
a sub-transmission having a low operating range and a high operating range with continuously variable gear ratios;
wherein the sub-transmission in the low operating range includes a friction clutch, and in the high operating range includes a jaw clutch.

2. A CVT transmission according to claim 1 , further comprising a direct-shift stage, wherein the direct-shift stage bridges the variator and is operatively directly connected to the input drive.

3. A CVT transmission according to claim 2 , wherein the direct-shift stage includes a jaw clutch.

4. A CVT transmission according to claim 1 , wherein the sub-transmission is positioned between the variator and a differential.

5. A CVT transmission according to claim 1 , wherein the sub-transmission is a planetary transmission having a planetary gear set including a sun gear, a ring gear, and planet gears meshed with the ring gear and the sun gear, wherein the planet gears are rotatably supported on a planet carrier that is configured to non-rotatably connect to a transmission output shaft.

6. The CVT transmission according to claim 5 , wherein the friction clutch of the sub-transmission is operatively connected to the ring gear and the jaw clutch of the sub-transmission is operatively connected to the planet carrier.

7. A method for operating a CVT transmission having an input drive, a continuously variable variator, and a sub-transmission comprising:
switching from a first operating range to a second operating range of the sub-transmission, wherein the first operating range is achieved using a friction clutch and the second operating range is achieved using a jaw clutch; and
selectively coupling, via a direct-shift stage, the input drive to an output independently of a start-up element, wherein the direct-shift stage includes a jaw clutch.

8. A method according to claim 7 , further comprising: performing quick resets from the second operating range to the first operating range utilizing the friction clutch of the sub-transmission in a slipping condition.

9. A method according to claim 7 , further comprising: performing a quick reset of a transmission ratio utilizing the friction clutch of the sub-transmission in a slipping condition and simultaneously adjusting the variator.

10. A method according to claim 7 , further comprising: performing a quick reset of a transmission ratio utilizing the friction clutch of the sub-transmission, and slipping the friction clutch without adjusting the variator.

11. A method according to claim 7 , further comprising: performing a quick reset of a transmission ratio directly from the second operating range to the first operating range without using the direct-shift stage.

Assignees

• Schaeffler Technologies Ag

Inventors

• Walter Bernhard

Classifications

• F16H2200/2094

  using positive clutches, e.g. dog clutches · CPC title

• F16H61/662 Primary

  with endless flexible members · CPC title

• F16H2200/2005

  with one sets of orbital gears · CPC title

• F16H2200/2064

  using at least one positive clutch, e.g. dog clutch · CPC title

• F16H3/54

  one of the central gears being internally toothed and the other externally toothed · CPC title