US 6,656,078 B1Granted

Family of six-speed planetary transmissions having three planetary gearsets and three input torque-transmitting mechanisms

AssigneeGeneral Motors Corporation

InventorsMadhusudan Raghavan, Norman Kenneth Bucknor, Patrick Benedict Usoro

Life of this patent

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Abstract

A family of multi-speed planetary transmissions has three planetary gearsets each with three planetary members and five torque-transmitting mechanisms. The transmission also has two interconnecting members, one of which interconnects a member of each of the planetary gearsets, and the other of which interconnects two members of the planetary gearsets. All of the transmission family members include one member continuously connected with a stationary member or transmission housing. In each family member, the input shaft of the transmission is selectively connectible with the planetary gearsets through three of the torque-transmitting mechanisms. The output shaft of the transmission is continuously connected with at least one member of the planetary gearset. The torque-transmitting mechanisms are selectively engaged in combinations of two to establish at least six forward speed ratios and one reverse speed ratio.

Claims9

Dependent claims

A family of six-speed transmissions, each family member comprising:

an input shaft;
an output shaft;
a transmission housing;
a planetary gear arrangement including a first planetary gearset, a second planetary gearset, a third planetary gearset, a first interconnecting member, a second interconnecting member, and five torque transmitting mechanisms;
said first planetary gearset having a first member, a second member, and a third member, said second planetary gearset having a first member, a second member, and a third member, said third planetary gearset having a first member, a second member, and a third member;
said first interconnecting member continuously interconnecting said first member of said first planetary gearset, said first member of said second planetary gearset, and said first member of said third planetary gearset;
said second interconnecting member continuously interconnecting said second member of said first planetary gearset and said second member of said second planetary gearset;
said second member of said third planetary gearset being continuously interconnected with said transmission housing;
said output shaft being continuously interconnected with at least one member of one of said planetary gearsets;
a first of said torque transmitting mechanisms being operable to selectively interconnect said input shaft with a member of a first group consisting of said members of said first and second planetary gearsets;
a second of said torque transmitting mechanisms being operable to selectively interconnect said input shaft with a member of a second group consisting of said members of said second and third planetary gearsets;
a third of said torque transmitting mechanisms being operable to selectively interconnect said input shaft with a member of a third group consisting of said members of said first, second, and third planetary gearsets;
a fourth of said torque transmitting mechanisms being operable to either selectively interconnect one member of said third group with another member of said third group or selectively interconnecting said transmission housing with a member of a fourth group consisting of said members of said second and third planetary gearsets and said interconnecting members;
a fifth of said torque transmitting mechanisms being operable to selectively interconnect said transmission housing with a member of said third group;
and
said five torque transmitting mechanisms being operable in combinations of two to establish six forward speed ratios and one reverse speed ratio between said input shaft and said output shaft through said planetary gear arrangement.

13 more elements

A family of six speed transmissions, each family member comprising:

an input shaft;
an output shaft;
a transmission housing;
a first planetary gearset having first, second, and third members;
a second planetary gearset having first, second, and third members;
a third planetary gearset having first, second, and third members, said second member being continuously interconnected with said transmission housing;
said output shaft being continuously interconnected with a member of a group consisting of said third members of said first and second planetary gearsets;
a first interconnecting member continuously interconnecting said first member of said first planetary gearset, said first member of said second planetary gearset, and said first member of said third planetary gearset;
a second interconnecting member continuously interconnecting said second member of said first planetary gearset and said second member of said second planetary gearset;
a first torque transmitting mechanism selectively interconnecting said input shaft with said second interconnecting member;
a second torque transmitting mechanism selectively interconnecting said input shaft with a member of a group consisting of said third members of said first and second planetary gearsets;
a third torque transmitting mechanism selectively interconnecting said input shaft with said third member of said third planetary gearset;
a fourth torque transmitting mechanism selectively interconnecting a member of a group consisting of said transmission housing and said third member of said third planetary gearset with a member of a group consisting of said interconnecting members;
a fifth torque transmitting mechanism selectively interconnecting said transmission housing with a member of a group consisting of said third member of said third planetary gearset and said second interconnecting member;
and
said torque transmitting mechanisms being selectively engaged in combinations of two to establish at least six forward speed ratios and one reverse speed ratio between said input shaft and said output shaft through at least one of said planetary gearsets.

13 more elements

Dependencies are inferred from the claim text.

Facts

Application: 10/161,868Filed 4 Jun 2002
Published: US 2003/0224901 A14 Dec 2003
Granted: 2 Dec 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

F16H 3/666
Composed of a number of gear trains without drive passing from one train to another: with intermeshing orbital gears
F16H 3/66
Gearings having three or more central gears: composed of a number of gear trains without drive passing from one train to another
F16H 2200/0052
Characterised by the number of forward speeds: the gear ratios comprising six forward speeds
F16H 2200/201
Characterised by the number of sets of orbital gears: with three sets of orbital gears