Title of Invention

A MULTISPEED TRANSMISSION HAVING TEN OR MORE SPEEDS

Abstract A transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices may include clutches and brakes. Moreover, the torque transmitting devices are selectively engageable in combinations of at least four to establish at least ten forward speed ratios and at least one reverse speed ratio between the input member and the output member
Full Text A TRANSMISSION
HAVING TEN OR MORE SPEEDS
CROSS-REFFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S Provisional
Application No. 60/986,697 filed on November 09, 2007. The disclosure of the
above application is incorporated herein by reference.
FIELD
[0002] The invention relates generally to a multiple speed transmission
having a plurality of planetary gear sets and a plurality of torque transmitting
devices, and more particularly to a transmission having ten or more speeds, four
planetary gear sets and a plurality of torque transmitting devices.
BACKGROUND
[0003] The statements in this section merely provide background
information related to the present disclosure and may or may not constitute prior
art.
[0004] A typical multiple speed transmission uses a combination of
friction clutches or brakes, planetary gear arrangements and fixed
interconnections to achieve a plurality of gear ratios. The number and physical
arrangement of the planetary gear sets, generally, are dictated by packaging,
cost and desired speed ratios.

[0005] While current transmissions achieve their intended purpose, the
need for new and improved transmission configurations which exhibit improved
performance, especially from the standpoints of efficiency, responsiveness and
smoothness and improved packaging, primarily reduced size and weight, is
essentially constant. Accordingly, there is a need for an improved cost-effective,
compact multiple speed transmission.
SUMMARY
[0006] A transmission is provided having an input member, an output
member, four planetary gear sets, a plurality of coupling members and a plurality
of torque transmitting devices. Each of the planetary gear sets includes first,
second and third members. The torque transmitting devices are for example
clutches and brakes.
[0007] In another aspect of the present invention a transmission is
provided having an input member, an output member and first, second, third apd
fourth planetary gear sets each having sun gears, carrier members and ring
gears. The input member is continuously interconnected with the sun gear of the
first planetary gear set and the output member is continuously interconnected
with the carrier member of the third planetary gear set. Additionally, a first
interconnecting member continuously interconnects the carrier member of the
first planetary gear set with the sun gear of the third planetary gear set, a second
interconnecting member continuously interconnects the carrier member of the
first planetary gear set with the ring gear of the second planetary gear set and, a

third interconnecting member continuously interconnects the ring gear of the third
planetary gear set with the carrier member of the fourth planetary gear set.
Further, a first torque transmitting device is selectively engageable to
interconnect the carrier member of the second planetary gear set with the sun
gear of the fourth planetary gear set, a second torque transmitting device is
selectively engageable to interconnect the ring gear of the first planetary gear set
with the carrier member of the third planetary gear set, a third torque transmitting
device is selectively engageable to interconnect the ring gear of the first
planetary gear set with the sun gear of the fourth planetary gear set, a fourth
torque transmitting device is selectively engageable to interconnect the carrier
member of the second planetary gear set with the ring gear of the fourth
planetary gear set, a fifth torque transmitting device is selectively engageable to
interconnect the ring gear of the fourth planetary gear set with a stationary
member and a sixth torque transmitting device is selectively engageable to
interconnect the sun gear of the second planetary gear set with the stationary
member. The torque transmitting devices are selectively engageable in
combinations of at least four to establish at least ten forward speeo ratios and at
least one reverse speed ratio between the input member and the output member.
[0008] It is thus an object of the present invention to provide a
transmission having four planetary gear sets.
[0009] It is a further object of the present invention to provide a
transmission having ten forward speeds and at least one reverse.

[0010] It is a still further object of the present invention to provide a
transmission having four planetary gear sets, a plurality of coupling members and
a plurality of torque transmitting devices.
[0011] Further objects, aspects and advantages of the present
invention will become apparent by reference to the following description and
appended drawings wherein like reference numbers refer to the same
component, element or feature.
DRAWINGS
[0012] The drawings described herein are for illustration purposes only
and are not intended to limit the scope of the present disclosure in any way
[0013] FIG. 1 is a lever diagram of an embodiment of a ten speed
transmission according to the present invention;
[0014] FIG. 2 is a diagrammatic view of an embodiment of a ten speed
transmission according to the present invention; and
[0015] FIG. 3 is a truth table presenting the state of engagement of the
various torque transmitting elements in each of the available forward and reverse
speeds or gear ratios of the transmission illustrated in FIGS. 1 and 2.
DETAILED DESCRIPTION
[0016] The following description is merely exemplary in nature ana is
not intended to limit the present disclosure, application, or uses.

[0017] At the outset, it should be appreciated that in the particular
example provided, the ten speed automatic transmission of the present invention
has an arrangement of permanent mechanical connections between the
elements of the four planetary gear sets. A first component or element of a first
planetary gear set is permanently coupled to a first component or element of a
second planetary gear set and to a first component or eiemer-t of a third
planetary gear set. A second component or element of the third planetary gear
set is permanently coupled to a second component or element of the fourth
planetary gear set.
[0018] Referring now to FIG. 1. an embodiment of a speed
transmission 10 is illustrated in a lever diagram format. A lever diagram is a
schematic representation of the components of a mechanical device such as an
automatic transmission. Each individual fever represents a planetary gear set
wherein the three basic mechanical components of the planetary gear set are
each represented by a node. Therefore, a single lever contains three nodes:
one for the sun gear, one for the planet gear carrier, and one for the ring gear.
The relative length between the nodes of each lever can be used to represent the
ring-to-sun ratio of each respective gear set. These lever ratios, in turn, are used
to vary the gear ratios of the transmission in order to achieve appropriate ratios
and ratio progression. Mechanical couplings or interconnections between the
nodes of the various planetary gear sets are illustrated by thin, horizontal lines
and torque transmitting devices such as clutches and brakes are presented as
interleaved fingers.. If the device is a brake, one set of the fingers is grounded.

Further explanation of the format, purpose and use of lever diagrams can be
found in SAE Paper 810102, "The Lever Analogy: A New Tool in Transmission
Analysis" by Benford and Leising which is hereby fully incorporated by reference
[0019] The transmission 10 includes an input shaft or member 12, a
first planetary gear set 14 having three nodes: a first node 14A, a second node
14B and a third node 14C, a second planetary gear set 16 having three nodes: a
first node 16A, a second node 16B and a third node 16C, a third planetary gear
set 18 having three nodes: a first node 18A, a second node 18B and a third node
18C, a fourth planetary gear set 20 having three nodes: a first node 20A, a
second node 20B and a third node 20C and an output shaft or member 22.
[0020] The input member 12 is coupled to the second node 14B of the
first planetary gear set 14. The output member 22 is coupled to the third node
18C of the third planetary gear set 18. The first node 14A of the first planetary
gear set 14 is coupled to the first node 16A of the second planetary gear set 16
and to the first node 18A of the third planetary gear set 18. The second node
18B of the third planetary gear set 18 is coupled to the second node 20B of the
fourth planetary gear set 20.
[0021] A first clutch 26 selectively connects the second node 16B of
the second planetary gear set 16 with the first node 20A of the fourth planetary
gear set 20. A second clutch 28 selectively connects the third node 14C of the
first planetary gear set 14 with the third node 18C of the third planetary gear set
18. A third clutch 30 selectively connects the third node 14C of the first planetary
gear set 14 with the first node 20A of the fourth planetary gear set 20. A fourth

clutch 32 selectively connects the second node 16B of the second planetary gear
set 16 with the third node 20C of the fourth planetary gear set 20. A first brake
34 selectively connects the third node 20C of the fourth planetary gear set 20
with a stationary element or a transmission housing 50. A second brake 36
selectively connects the third node 16C of the second planetary gear set 16 with
a stationary element or the transmission housing 50.
[0022] Referring now to FIG. 2, a stick diagram presents a schematic
layout of the embodiment of the ten speed transmission 10 according to the
present invention. In FIG. 2, the numbering from the lever diagram of FIG 11 is
carried over. The clutches, brakes, and couplings are correspondingly presented
whereas the nodes of the planetary gear sets now appear as components ;of
planetary gear sets such as sun gears, ring gears, planet gears and planet gear
carriers.
[0023] For example, the planetary gear set 14 includes a sun gear
member 14B, a ring gear member 14C, and a planet gear earner member 14A
that rotatably supports a set of planet gears 14D (only one of which is shown).
The planet gears 14D are each configured to intermesh with both the sun ge,ar
member 14B and the ring gear member 14C. The planet carrier member 14A; is
connected for common rotation with a first shaft or intermediate member 42 and
a second shaft or intermediate member 44. The sun gear member 14B is
connected for common rotation with input shaft or member 12. The ring gear
member 14C is connected for common rotation with a third shaft or intermediate
member 46.

[0024] The planetary gear set 16 includes a sun gear member 16C, a
ring gear member 16A, and a planet gear carrier member 166 that rotatably
supports a set of planet gears 16D (only one of which is shown). The planet
gears 160 are each configured to intermesh with both the sun gear member 16C
and the ring gear member 16A. The ring gear member 16A s connected for
common rotation with second shaft or intermediate member 44. The planet
carrier member 16B is connected for common rotation with a fourth intermediate
member 48. The sun gear member 16C is connected for common rotation with a
fifth shaft or intermediate member 52.
[0025] The planetary gear set 18 includes a sun gear member 18A, a
ring gear member 18B, and a planet gear carrier member 18C that rotatably
supports a set of planet gears 18D (only one of which is shown). The planet
gears 18D are each configured to intermesh with both the sun gear member 18A
and the ring gear member 18B. The sun gear member 18A is connected for
common rotation with the first shaft or intermediate member 42 The ring gear
member 18B is connected for common rotation with a sixth shaft or intermediate
member 54. The planet carrier member 18C is connected for common rotation
with a seventh shaft or intermediate member 56 and output shaft or member 22.
[0026] The planetary gear set 20 includes a sun gear member 20A, a
ring gear member 20C, and a planet gear carrier member 20B that rotatably
supports a set of planet gears 20D (only one of which is shown). The set of
planet gears 20D are each configured to intermesh with both the sun gear
member 20A and the ring gear member 20C. The sun gear member 20A,is

connected for common rotation with an eighth shaft or intermediate member 58.
The planet carrier member 20B is connected for common rotation with sixth shaft
or intermediate member 54. The ring gear member 20C is connected for
common rotation with the ninth intermediate member 60.
[0027] The input shaft or member 12 is continuously connected to an
engine (not shown) or to a turbine of a torque converter (not shown). The output
shaft or member 22 is continuously connected with the final drive unit or transfer
case (not shown).
[0028] The torque-transmitting mechanisms or the clutches 26, 28. 30,
32 and the brakes 34 and 36 allow for selective interconnection of the shafts or
intermediate members, members of the planetary gear sets and the housing. For
example, the first clutch 26 is selectively engageable to connect fourth
intermediate member 48 with the eighth intermediate member 58. The second
clutch 28 is selectively engageable to connect the third intermediate shaft for
member 46 with the seventh intermediate shaft or member 56. The third clutph
30 is selectively engageable to connect the third intermediate shaft or member
46 with the eighth intermediate shaft or member 58. The fourth clutch 32 is
selectively engageabfe to connect the fourth intermediate member 48 with the
ninth intermediate member 60. The first brake 34 is selectively engageable to
connect the ninth intermediate member 60 with a stationary element or the
transmission housing 50 in order to prevent the ninth intermediate member 60
from rotating relative to the transmission housing 50. The second brake 36 is
selectively engageable to connect the fifth intermediate member 52 with a

stationary element or the transmission housing 50 in order to prevent the fifth
intermediate member 52 from rotating relative to the transmission Housing 50
[0029] Referring now to FIGS. 2 and 3, the operation of the
embodiment of the ten speed transmission 10 will be described It will be
appreciated that the transmission 10 is capable of transmitting torque from the
input shaft or member 12 to the output shaft or member 22 in at least ten forward
speed or torque ratios and at least one reverse speed or torque ratio with a triple
overdrive. Each forward and reverse speed or torque ratio s attained by
engagement of one or more of the torque-transmitting mechanisms (i.e. first
clutch 26, second dutch 28, third clutch 30, fourth clutch 32, first brake 34 and
second brake 36), as will be explained below. FIG. 3 is a truth table presenting
the various combinations of torque-transmitting elements that are activated for
engaged to achieve the various gear states. Actual numerical gear ratios of the
various gear states are also presented although it should be appreciated that
these numerical values are exemplary only and that they may be adjusted over
significant ranges to accommodate various applications and operational criteria
of the transmission 10. An example of the gear ratios that may be obtained using
the embodiments of the present invention are also shown in FIG. 3 Of course,
other gear ratios are achievable depending on the gear diameter gear teeth
count and gear configuration selected.
[0030] To establish reverse gear, the first clutch 26, the third clutch 3,0.
the first brake 34 and the second brake 36 are engaged or activated. The first
clutch 26 connects the fourth intermediate member 48 with the eighth

intermediate member 58. The third clutch 30 connects the third intermediate
shaft or member 46 with the eighth intermediate shaft or member 58. The first
brake 34 connects the ninth intermediate member 60 with a stationary element or
the transmission housing 50 in order to prevent the ninth intermediate member
60 from rotating relative to the transmission housing 50. The second brake 36
connects the fifth intermediate member 52 with a stationary element or the
transmission housing 50 in order to prevent the fifth intermediate member 52
from rotating relative to the transmission housing 50. Likewise, the ten forward
ratios are achieved through different combinations of clutch and brake
engagement, as shown in FIG. 3.
[0031] It will be appreciated that the foregoing explanation of operation
and gear states of the ten speed transmission 10 assumes, first of all, that all the
clutches and brakes not specifically referenced in a given gear state are inactive
or disengaged and, second of all, that during gear shifts, i.e., changes of gear
state, between at least adjacent gear states, a clutch or brake engaged or
activated in both gear states will remain engaged or activated.
[0032] The description of the invention is merely exemplary in nature
and variations that do not depart from the gist of the invention are intended to be
within the scope of the invention. Such variations are not to be regarded as a
departure from the spirit and scope of the invention.

What is claimed is:
1. A transmission comprising:
an input member;
an output member;
first, second, third and fourth planetary gear sets each having first, second
and third members;
a first interconnecting member continuously interconnecting the first
member of the first planetary gear set with the first member of the third planetary
gear set;
a second interconnecting member continuously interconnecting the first
member of the first planetary gear set with the first member of the second
planetary gear set;
a third interconnecting member continuously interconnecting the second
member of the third planetary gear set with the second member of the fourth
planetary gear set; and
six torque transmitting devices selectively engageable to interconnect one
of the first, second, and third members with at least one other of the first
members, second members, third members, and a stationary member and
wherein the torque transmitting devices are selectively engageable in
combinations of at least four to establish at least ten forward speed ratios and at
least one reverse speed ratio between the input member and the output member.

2. The transmission of claim 1 wherein a first of the six torque
transmitting devices is selectively engageable to interconnect the second
member of the second planetary gear set with the first member of the fourth
planetary gear set.
3. The transmission of claim 2 wherein a second of the six torque
transmitting devices is selectively engageable to interconnect the third member
of the first planetary gear set with the third member of the third olanetary gear
set.
4. The transmission of claim 3 wherein a third of the six torque
transmitting devices is selectively engageable to interconnect the third member
of the first planetary gear set with the first member of the fourth planetary gear
set.
5. The transmission of claim 4 wherein a fourth of the six torque
transmitting devices is selectively engageable to interconnect the second
member of the second planetary gear set with the third member of the fourth
planetary gear set.
6. The transmission of claim 5 wherein a fifth of the six torque
transmitting devices is selectively engageable to interconnect the thud member
of the fourth planetary gear set with the stationary member.

7. The transmission of claim 6 wherein a sixth of the six torque
transmitting devices is selectively engageable to interconnect the third member
of the second planetary gear set with the stationary member.
8. The transmission of claim 1 wherein the second member of the first
planetary gear set, the third member of the second planetary gear set, the first
member of the third planetary gear set and the first member of the fourth
planetary gear set are sun gears, the first member of the first planetary gear set,
the second member of the second planetary gear set, the third member of the
third planetary gear set and the second member of the fourth planetary gear set
are carrier members and the third member of the first planetary gear set, the first
member of the second planetary gear set, the second member of the third
planetary gear set and the third member of the fourth planetary gear set are ring
gears.
9. The transmission of claim 1 wherein the input member is
continuously interconnected with the second member of the first planetary gear
set and wherein the output member is continuously interconnected with the third
member of the third planetary gear set.

10. The transmission of claim 1 wherein two of the six torque
transmitting devices are brakes and four of the six torque transmitting devices
are clutches.
11. The transmission of claim 1 wherein the stationary member is a
transmission housing.

12. A transmission comprising:
an input member;
an output member;
first, second, third and fourth planetary gear sets each having first, second
and third members, wherein the input member is continuously interconnected
with the second member of the first planetary gear set and wherein the output
member is continuously interconnected with the third member of the third
planetary gear set;
a first interconnecting member continuously interconnecting the first
member of the first-planetary gear set with the first member of the third planetary
gear set;
a second interconnecting member continuously interconnecting the first
member of the first planetary gear set with the first member of the second
planetary gear set;
a third interconnecting member continuously interconnecting the second
member of the third planetary gear set with the second member of the fourth
planetary gear set; and
a first torque transmitting device selectively engageable to interconnect
the second member of the second planetary gear set with the first member of the
fourth planetary gear set;
a second torque transmitting device selectively engageable to
interconnect the third member of the first planetary gear set with the third
member of the third planetary gear set;

a third torque transmitting device selectively engageable to interconnect
the third member of the first planetary gear set with the first member of the fourth
planetary gear set;
a fourth torque transmitting device selectively engageable to interconnect
the second member of the second planetary gear set with the third member of
the fourth planetary gear set; and
a fifth torque transmitting device selectively engageable to interconnect
the third member of the fourth planetary gear set with a stationary member;
a sixth torque transmitting device selectively engageable to interconnect
the third member of the second planetary gear set with the stationary member,
and
wherein the torque transmitting devices are selectively engageable on
combinations of at least four to establish at least ten forward speed ratios and at
least one reverse speed ratio between the input member and the output member
13. The transmission of claim 12 wherein the second member of the
first planetary gear set, the third member of the second planetary gear set, the
first member of the third planetary gear set and the first member of the fourth
planetary gear set are sun gears, the first member of the first planetary gear set,
the second member of the second planetary gear set, the third member of the
third planetary gear set and the second member of the fourth planetary gear set
are carrier members and the third member of the first planetary gear set, the first
member of the second planetary gear set, the second member set, the third

planetary gear set and the third member of the fourth planetary gear set are ring
gears.
14. The transmission of claim 12 wherein the stationary member is a
transmission housing.

15. A transmission comprising:
an input member;
an output member;
first, second', third and fourth planetary gear sets each having sun gears,
carrier members and ring gears, the input member is continuously interconnected
with the sun gear of the first planetary gear set and wherein the output member is
continuously interconnected with the carrier member of the third olanetary gear
set;
a first interconnecting member continuously interconnecting the carrier
member of the first planetary gear set with the sun gear of the third planetary
gear set;
a second interconnecting member continuously interconnecting the carrier
member of the first planetary gear set with the ring gear of the second planetary
gear set;
a third interconnecting member continuously interconnecting the ring gear
of the third planetary gear set with the carrier member of the fourth planetary
gear set; and
a first torque transmitting device selectively engageable to interconnect
the carrier member of the second planetary gear set with the sun gear of the
fourth planetary gear set;
a second torque transmitting device selectively engageable ,to
interconnect the ring gear of the first planetary gear set with the carrier member
of the third planetary gear set;

a third torque transmitting device selectively engageable to interconnect
the ring gear of the first planetary gear set with the sun gear of the fourth
planetary gear set;
a fourth torque transmitting device selectively engageable to interconnect
the carrier member of the second planetary gear set with the ing gear of the
fourth planetary gear set; and
a fifth torque transmitting device selectively engageable to interconnect
the ring gear of the fourth planetary gear set with a stationary member;
a sixth torque transmitting device selectively engageable to interconnect
the sun gear of the second planetary gear set with the stationary member; and
wherein the torque transmitting devices are selectively engageable in
combinations of at least four to establish at least ten forward speed ratios and at
least one reverse speed ratio between the input member and the output member.
16. The transmission of claim 15 wherein the stationary member is a
transmission housing.

A transmission is provided having an input member, an output member, four planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes first, second and third members. The torque transmitting devices may include clutches and
brakes. Moreover, the torque transmitting devices are selectively engageable in
combinations of at least four to establish at least ten forward speed ratios and at least one reverse speed ratio between the input member and the output member

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=bMqwzS3XWPww0w4NwUI7+g==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 269823
Indian Patent Application Number 1741/KOL/2008
PG Journal Number 46/2015
Publication Date 13-Nov-2015
Grant Date 09-Nov-2015
Date of Filing 15-Oct-2008
Name of Patentee GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Applicant Address 300 GM RENAISSANCE CENTER DETROIT, MICHIGAN
Inventors:
# Inventor's Name Inventor's Address
1 CLINTON E. CAREY 215 RIVERVIEW AVENUE MONROE, MICHIGAN 48162
2 SCOTT H. WITTKOPP 6189 OAKHURST DRIVE, YPSILANTI, MICHIGAN 48197
3 JAMES M. HART 16011 HAGGERTY BELLEVILLE, MICHIGAN 48111
4 ANDREW W. PHILLIPS 4130 HOLLY LANE ROCHESTER, MICHIGAN 48306
PCT International Classification Number F16H3/62; F16H3/44
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/986,697 2007-11-09 U.S.A.