Multi-speed planetary transmission

Patent metadata

Field	Value
Publication number	US-11788608-B2
Application number	US-202117802207-A
Country	US
Kind code	B2
Filing date	Feb 18, 2021
Priority date	Feb 25, 2020
Publication date	Oct 17, 2023
Grant date	Oct 17, 2023

Abstract

A multi-speed transmission including a plurality of planetary gearsets and a plurality of selective couplers to achieve at least ten forward speed ratios is disclosed. The plurality of planetary gearsets may include a first planetary gearset, a second planetary gearset, a third planetary gearset, and a fourth planetary gearset. The plurality of selective couplers may include a number of clutches and a number of brakes. The multi-speed transmission may have four planetary gearsets and seven selective couplers. The seven selective couplers may include three clutches and four brakes.

First claim

What is claimed is:

1. A transmission comprising:
at least one stationary member;
an input member rotatable relative to the at least one stationary member;
a plurality of planetary gearsets operatively coupled to the input member, each of the plurality of planetary gearsets including a first gearset component, a second gearset component, and a third gearset component, the plurality of planetary gearsets including a first planetary gearset, a second planetary gearset, a third planetary gearset, and a fourth planetary gearset, wherein a planet carrier of the third planetary gearset is fixedly coupled to a sun gear of the fourth planetary gearset;
an output member operatively coupled to the input member through the plurality of planetary gearsets and rotatable relative to the at least one stationary member; and
a plurality of selective couplers including a first number of clutches and a second number of brakes,
wherein the output member is fixedly coupled to the fourth planetary gearset and the input member is:
(i) fixedly coupled to the first planetary gearset;
(ii) selectively coupled through a first clutch of the plurality of selective couplers, when engaged, to both the second planetary gearset and the third planetary gearset; and
(iii) selectively coupled through a second clutch of the plurality of selective couplers, when engaged, to both the second planetary gearset and the third planetary gearset independent of the first clutch.

2. The transmission of claim 1 , wherein the first clutch, when engaged, couples the input member to the first gearset component of the second planetary gearset and to the first gearset component of the third planetary gearset.

3. The transmission of claim 2 , wherein the first gearset component of the first planetary gearset is a first sun gear, the first gearset component of the second planetary gearset is a second sun gear, the first gearset component of the third planetary gearset is a third sun gear, the first gearset component of the fourth planetary gearset is the sun gear of the fourth planetary gearset.

4. The transmission of claim 2 , wherein the second clutch, when engaged, couples the input member to the second gearset component of the second planetary gearset and to the third gearset component of the third planetary gearset.

5. The transmission of claim 4 , wherein the first gearset component of the first planetary gearset is a first sun gear, the first gearset component of the second planetary gearset is a second sun gear, the first gearset component of the third planetary gearset is a third sun gear, the first gearset component of the fourth planetary gearset is the sun gear of the fourth planetary gearset, the second gearset component of the first planetary gearset is a first planet carrier, the second gearset component of the second planetary gearset is a second planet carrier, the second gearset component of the third planetary gearset is the planet carrier of the third planetary gearset, the second gearset component of the fourth planetary gearset is a fourth planet carrier, the third gearset component of the first planetary gearset is a first ring gear, the third gearset component of the second planetary gearset is a second ring gear, the third gearset component of the third planetary gearset is a third ring gear, and the third gearset component of the fourth planetary gearset is a fourth ring gear.

6. The transmission of claim 1 , wherein the second clutch, when engaged, couples the input member to the second gearset component of the second planetary gearset and to the third gearset component of the third planetary gearset.

7. The transmission of claim 6 , wherein the first gearset component of the first planetary gearset is a first sun gear, the first gearset component of the second planetary gearset is a second sun gear, the first gearset component of the third planetary gearset is a third sun gear, the first gearset component of the fourth planetary gearset is the sun gear of the fourth planetary gearset, the second gearset component of the first planetary gearset is a first planet carrier, the second gearset component of the second planetary gearset is a second planet carrier, the second gearset component of the third planetary gearset is the planet carrier of the third planetary gearset, the second gearset component of the fourth planetary gearset is a fourth planet carrier, the third gearset component of the first planetary gearset is a first ring gear, the third gearset component of the second planetary gearset is a second ring gear, the third gearset component of the third planetary gearset is a third ring gear, and the third gearset component of the fourth planetary gearset is a fourth ring gear.

8. The transmission of claim 1 , wherein the second number is greater than the first number.

9. The transmission of claim 8 , wherein the second number is four and the first number is three.

10. The transmission of claim 1 , wherein the third gearset component of the first planetary gearset is a first ring gear, the third gearset component of the second planetary gearset is a second ring gear, the third gearset component of the third planetary gearset is a third ring gear, and the third gearset component of the fourth planetary gearset is a fourth ring gear, wherein
a first brake of the plurality of selective couplers, when engaged, fixedly couples the first ring gear of the first planetary gearset to the at least one stationary member;
a second brake of the plurality of selective couplers, when engaged, fixedly couples the second ring gear of the second planetary gearset to the at least one stationary member;
a third brake of the plurality of selective couplers, when engaged, fixedly couples the third ring gear of the third planetary gearset to the at least one stationary member; and
a fourth brake of the plurality of selective couplers, when engaged, fixedly couples the fourth ring gear of the fourth planetary gearset to the at least one stationary member.

11. The transmission of claim 1 , wherein the input member is fixedly coupled to the first gearset component of the first planetary gearset.

12. The transmission of claim 11 , wherein the output member is fixedly coupled to the second gearset component of the fourth planetary gearset.

13. The transmission of claim 1 , further comprising
a first interconnector which fixedly couples the second gearset component of the first planetary gearset and the third gearset component of the second planetary gearset together;
a second interconnector fixedly couples the second gearset component of the second planetary gearset and the third gearset component of the third planetary gearset together; and
a third interconnector which fixedly couples the first gearset component of the second planetary gearset and the first gearset component of the third planetary gearset together.

14. The transmission of claim 13 , wherein the first gearset component of the first planetary gearset is a first sun gear, the first gearset component of the second planetary gearset is a second sun gear, the first gearset component of the third planetary gearset is a third sun gear, the first gearset component of the fourth planetary gearset is the sun gear of the fourth planetary gearset, the second gearset component of the first planetary gearset is a first planet carrier, the second gearset component of the second planetary gearset is a second planet carrier, the second gearset component of the third planetary gearset is the planet carrier of the third planetary gearset, the second gearset component of the fourth planetary gearset is a fourth planet carrier, the thir

Assignees

• Allison Transm Inc

Inventors

• Patel Nayan
• Briceno Jorge F
• Rockey Conrad

Classifications

• F16H3/66 Primary

  composed of a number of gear trains without drive passing from one train to another · CPC title

• F16H2200/0069

  the gear ratios comprising ten forward speeds · CPC title

• F16H2200/2012

  with four sets of orbital gears · CPC title

• F16H2200/2048

  with seven engaging means · CPC title

• F16H2003/445

  without permanent connection between the input and the set of orbital gears · CPC title