Title of Invention

GEAR AND CLUTCH ARRANGEMENT FOR MULTI-SPEED TRANSMISSION

Abstract A transmission is disclosed having an input member, an output member, three planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes a sun gear member, a planet carrier member, and a ring gear member. The torque transmitting devices include five clutches and one brake arranged within a transmission housing.
Full Text GEAR AND CLUTCH ARRANGEMENT FOR
MULTI-SPEED TRANSMISSION
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/984,550, filed on November 1, 2007, which is hereby
incorporated in its entirety 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 eight or more speeds,
three 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] Automatic power transmissions are currently in widespread use
in passenger vehicles and trucks. As is well known, the automatic transmission
provides a plurality of speed ratios in the forward direction and at least one speed
ratio in the reverse direction. The speed ratios are established through the use
of a plurality of planetary gearsets. The engagement of the gearsets is controlled

by a number of fluid-operated torque transmitting mechanisms, for example
clutches and brakes.
[0005] It has become a standard to provide at least four forward speed
ratios in automatic transmissions for use in passenger vehicles. More recently,
automobile manufacturers have increased the forward speed ratios to six and in
some instances seven or eight. This, of course, requires the addition of
planetary gearsets. However, it is desirable to minimize the number of torque
transmitting mechanisms to reduce cost and overall size of the transmission.
[0006] A number of the currently proposed eight speed planetary
transmissions provide three planetary gearsets and six torque-transmitting
mechanisms. One problem facing transmission designers and manufacturers is
the packaging of the planetary gearsets and the torque-transmitting mechanisms.
It is preferable to arrange the gearsets and torque-transmitting mechanisms in a
way that minimizes the overall size of the transmission as well as reduces
manufacturing complexity.
[0007] Therefore, there is a need for a new and improved multi-speed
transmission. The arrangement of the gearsets and the torque-transmitting
mechanisms of the transmission should minimize the size and manufacturing
complexity of the transmission.
SUMMARY
[0008] In an aspect of the present invention, a multi-speed
transmission is provided. The transmission has an input member, an output

member, a transmission housing, a first, second, and third planetary gear set,
five clutches and one brake.
[0009] The transmission housing has a first wall, a second wall, and a
third wall extending between the first and second walls. The third planetary gear
set is adjacent the first wall. The second planetary gear set is adjacent second
wall. The first planetary gear set is between the second and third planetary gear
sets. Each planetary gear set has a sun gear member, a ring gear member and
a planet carrier member supporting a plurality of planet gears each configured to
intermesh with at least one of the sun gear member and the ring gear member.
[0010] The output member is continuously interconnected with the ring
gear member of the third planetary gear set. The input member is continuously
interconnected with the sun gear member of the second planetary gear set.
[0011] The sun gear member of the first planetary gear set is
permanently coupled to the transmission housing. The planet carrier member of
the second planetary gear set is permanently coupled to the planet carrier
member of the third planetary gear set.
[0012] The transmission housing has a first area defined radially
inward from an outer periphery of the planetary gear sets and axially bounded by
the first wall and the third planetary gear set, a second area defined radially
inward from the outer periphery of the planetary gear sets and axially bounded by
the first and third planetary gear sets, a third area defined radially inward from
the outer periphery of the planetary gear sets and axially bounded by the first and
second planetary gear sets, a fourth area defined radially inward from the outer

periphery of the planetary gear sets and axially bounded by the second planetary
gear set and the second wall, and a fifth area defined radially inward from the
third wall and radially outward from the outer periphery of the planetary gear sets
and axially bounded by the first wall and the second wall.
[0013] The first of the five clutches is selectively engageable to
interconnect the input member with the planet carrier member of the first
planetary gear set. The second of the five clutches is selectively engageable to
interconnect the input member with the ring gear member of the second
planetary gear set. The third of the five clutches is selectively engageable to
interconnect the planet carrier member of the first planetary gear set with the sun
gear member of the third planetary gear set. The fourth of the five clutches is
selectively engageable to interconnect the ring gear member of the first planetary
gear set with the sun gear member of the third planetary gear set. The fifth of the
five clutches is selectively engageable to interconnect the ring gear member of
the first planetary gear set with the ring gear member of the second planetary
gear set. The brake is selectively engageable to interconnect the planet carrier
member of the third planetary gear set to the transmission housing.
[0014] The first of the five clutches is disposed in the third area. The
second of the five clutches is disposed in at least one of the third and fourth
areas. The third of the five clutches is disposed in the second area. The fourth of
the five clutches is disposed in second area. The fifth of the five clutches is
disposed in at least one of the third, fourth and fifth areas. The brake is disposed
in the first area.

[0015] The clutches and the brake are selectively engageable to
establish at least eight forward speed ratios and at least one reverse speed ratio
between the input member and the output member.
[0016] Further areas of applicability will become apparent from the
description provided herein. It should be understood that the description and
specific examples are intended for purposes of illustration only and are not
intended to limit the scope of the present disclosure.
DRAWINGS
[0017] The drawings described herein are for illustration purposes only
and are not intended to limit the scope of the present disclosure in any way.
[0018] FIG. 1 is a diagram of a cross-section of a transmission
according to the principles of the present invention.
DETAILED DESCRIPTION
[0019] The following description is merely exemplary in nature and is
not intended to limit the present disclosure, application, or uses.
[0020] Referring now to FIG. 1, an embodiment of a multi-speed
transmission is generally indicated by reference number 10. The transmission 10
includes a transmission housing 11, an input shaft or member 12, and an output
shaft or member 14. The input member 12 is preferably connected to an engine
(not shown) or to a turbine of a torque converter (not shown). The output
member 14 is preferably connected with a final drive unit (not shown) or transfer

case (not shown). In the example provided, the output member 14 is coaxial with
a longitudinal axis defined by the input member 12. Accordingly, the output
member 14 may exit on an opposite side of the transmission 10 as the input
member 12, thereby providing, for example, a rear wheel drive transmission
configuration.
[0021] The transmission 10 includes a first planetary gear set 16, a
second planetary gear set 18, and a third planetary gear set 20. The planetary
gear sets 16, 18, and 20 are connected between the input member 12 and the
output member 14. In a preferred embodiment of the present invention, the first
planetary gear set 16 is a planetary gear set that includes a sun gear member
22, a ring gear member 24 and a carrier member 28 that rotatably supports a set
of pinion gears 32, 34. Pinion gears 32, 34 are configured to intermesh with
each other, sun gear member 22 and ring gear member 24. Moreover, sun gear
member 22 is fixedly connected to the transmission housing 11 of the
transmission 10 for preventing rotation of sun gear member 22. Ring gear
member 24 is connected for common rotation with a first interconnecting shaft or
member 38 and a second interconnecting shaft or member 39. Carrier member
28 is connected for common rotation with a third interconnecting shaft or member
40 and a fourth interconnecting shaft or member 45.
[0022] The second planetary gear set 18 includes a sun gear member
42, a ring gear member 44 and a carrier member 46 that rotatably supports a set
of pinion gears 48. Pinion gears 48 are configured to intermesh with both sun
gear member 42 and ring gear member 44. Sun gear member 42 is connected

for common rotation with the input member 12 and a fifth interconnecting shaft or
member 43. Carrier member 46 is connected for common rotation with a sixth
interconnecting shaft or member 47. Ring gear member 44 is connected for
common rotation with a seventh interconnecting shaft or member 50.
[0023] The third planetary gear set 20 includes a sun gear member 52,
a ring gear member 54 and a carrier member 56 that rotatably supports a set of
pinion gears 58. Pinion gears 58 are configured to intermesh with both sun gear
member 52 and ring gear member 54. Sun gear member 52 is connected for
common rotation with an eighth interconnecting shaft or member 60. Ring gear
member 54 is connected for common rotation with the output member 14.
Carrier member 56 is connected for common rotation with the sixth
interconnecting member 47.
[0024] The transmission 10 includes a variety of torque-transmitting
mechanisms or devices including a first clutch 70, a second clutch 72, a third
clutch 74, a fourth clutch 76, a fifth clutch 78, and a brake 80. The first clutch 70
is selectively engagable to connect the fifth interconnecting member 43 with the
fourth interconnecting member 45. The second clutch 72 is selectively
engagable to connect the fifth interconnecting member 43 with the seventh
interconnecting member 50. The third clutch 74 is selectively engagable to
connect the third interconnecting member 40 with the eighth interconnecting
member 60. The fourth clutch 76 is selectively engagable to connect the second
interconnecting member 39 to the eighth interconnecting member 60. The fifth
clutch 78 is selectively engagable to connect the first interconnecting member 38

to the seventh interconnecting member 50. The brake 80 is selectively
engagable to connect carrier member 56 to the transmission housing 11 to
restrict rotation of carrier member 56.
[0025] The transmission 10 is capable of transmitting torque from the
input member 12 to the output member 14 in preferably at least eight forward
torque ratios and two reverse torque ratios. Each of the forward torque ratios
and the reverse torque ratios are attained by engagement of one or more of the
torque-transmitting mechanisms (i.e. first clutch 70, second clutch 72, third clutch
74, fourth clutch 76, fifth clutch 78, and brake 80). Those skilled in the art will
readily understand that a different speed ratio is associated with each torque
ratio. Thus, eight forward speed ratios may be attained by the transmission 10.
[0026] The transmission housing 11 includes a first end wall 102, a
second end wall 104, and a third wall 106. The third wall 106 interconnects
between the first and second end walls 102 and 104 to provide a space or cavity
108 in which the planetary gear sets 16, 18, and 20 and the torque-transmitting
mechanisms 70, 72, 74, 76, 78, and 80 are located. Further, the cavity 108 has
a plurality of areas or Zones A, B, C, D, and E in which the plurality of torque
transmitting mechanisms 70, 72, 74, 76, 78, and 80 are specifically positioned, in
accordance with the preferred embodiments of the present invention.
[0027] As shown in FIG. 1, Zone A is defined by the area or space
bounded: axially on the left by the first end wall 102, on the right by planetary
gear set 20, radially inward by a reference line "L" which is a longitudinal line that
is axially aligned with the input shaft 12, and radially outward by a reference line

"M" which is a longitudinal line that extends adjacent an outer diameter or outer
periphery of the planetary gear sets 16, 18, and 20. While reference line "M" is
illustrated as a straight line, it should be appreciated that reference line "M"
follows the outer periphery of the planetary gear sets 16, 18, and 20, and
accordingly may be stepped or non-linear depending on the location of the outer
periphery of each of the planetary gear sets 16, 18, and 20. Zone B is defined
by the area bounded: axially on the left by planetary gear set 20, axially on the
right by planetary gear set 16, radially outward by reference line "M", and radially
inward by reference line "L". Zone C is defined by the area bounded: axiaiiy on
the left by planetary gear set 16, axially on the right by planetary gear set 18,
radially outward by reference line "M", and radially inward by reference line "L".
Zone D is defined by the area bounded: axially on the left by planetary gear set
18, axially on the right by the second end wall 104, radially outward by reference
line "M", and radially inward by reference line "L". Zone E is defined by the area
bounded: axially on the left by the first end wall 102, axially on the right by the
second end wall 104, radially inward by reference line "M" and radially outward
by the third wall 106.
[0028] The torque transmitting mechanisms 70, 72, 74, 76, 78, and 80
are intentionally located within specific Zones in order to provide advantages in
overall transmission size, packaging efficiency, and reduced manufacturing
complexity. In the particular example shown in FIG. 1, the torque transmitting
mechanism 80 is in Zone A, the torque transmitting mechanisms 74 and 76 are in
Zone B, and the torque transmitting mechanisms 70, 72 and 78 are in Zone C.

[0029] However, the present invention contemplates other
embodiments where the torque transmitting mechanisms 70, 72, 74, 76, 78, and
80 are disposed in the other Zones. The feasible locations of the torque-
transmitting devices 70, 72, 74, 76, 78, and 80 relative to the Zones are
illustrated in Chart 1. An "X" in the chart indicates that the present invention
contemplates locating the particular torque transmitting device in the referenced
Zones. An "O" in the chart indicates that the present invention contemplates that
it is not feasible to locate the particular torque transmitting device in the
referenced Zone.

[0030] For example, the present invention provides that brake 80 may
be located in Zone A, but may not be located in Zones B, C, D or E. It should be
appreciated that each of the torque transmitting devices 70, 72, 74, 76, 78, and
80 may be located in a permissible Zone, as indicated in Chart 1, independently
of the location of any of the other torque transmitting devices 70, 72, 74, 76, 78,
and 80.
[0031] 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.

CLAIMS:
1. A transmission comprising:
an input member;
an output member;
a transmission housing having a first wall, a second wall, and a third wall
extending between the first and second walls;
a first, second and third planetary gear set disposed within the
transmission housing, wherein the third planetary gear set is adjacent the first
wall, the second planetary gear set is adjacent second wall, and the first
planetary gear set is between the second and third planetary gear sets, each
planetary gear set having a sun gear member, a ring gear member and a planet
carrier member supporting a plurality of planet gears each configured to
intermesh with at least one of the sun gear member and the ring gear member,
wherein the output member is continuously interconnected with the ring gear
member of the third planetary gear set, wherein the input member is continuously
interconnected with the sun gear member of the second planetary gear set,
wherein the sun gear member of the first planetary gear set is permanently
coupled to the transmission housing, wherein the planet carrier member of the
second planetary gear set is permanently coupled to the planet carrier member
of the third planetary gear set, and;
wherein the transmission housing has a first area defined radially inward
from an outer periphery of the planetary gear sets and axially bounded by the
first wall and the third planetary gear set, a second area defined radially inward
from the outer periphery of the planetary gear sets and axially bounded by the
first and third planetary gear sets, a third area defined radially inward from the
outer periphery of the planetary gear sets and axially bounded by the first and
second planetary gear sets, a fourth area defined radially inward from the outer
periphery of the planetary gear sets and axially bounded by the second planetary
gear set and the second wall, and a fifth area defined radially inward from the

third wall and radially outward from the outer periphery of the planetary gear sets
and axially bounded by the first wall and the second wall;
a first clutch selectively engageable to interconnect the input member and
the sun gear member of the second planetary gear set with the planet carrier
member of the first planetary gear set;
a second clutch selectively engageable to interconnect the input member
and the sun gear member of the second planetary gear set with the ring gear
member of the second planetary gear set;
a third clutch selectively engageable to interconnect the planet carrier
member of the first planetary gear set with the sun gear member of the third
planetary gear set;
a fourth clutch selectively engageable to interconnect the ring gear
member of the first planetary gear set with the sun gear member of the third
planetary gear set;
a fifth clutch selectively engageable to interconnect the ring gear member
of the first planetary gear set with the ring gear member of the second planetary
gear set;
a brake selectively engageable to interconnect the planet carrier member
of the third planetary gear set to the transmission housing;
wherein the first clutch is disposed in the third area, the second clutch is
disposed in at least one of the third and fourth areas, the third clutch is disposed
in the second area, the fourth clutch is disposed in second area, the fifth clutch is
disposed in at least one of the third, fourth and fifth areas, and the brake is
disposed in the first area; and
wherein the clutches and the brake are selectively engageable to establish
at least eight 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 the first clutch is disposed in
the third area, the second clutch is disposed in the third area, the third clutch is

disposed in the second area, the fourth clutch is disposed in the second area, the
fifth clutch is disposed in the third area, and the brake is disposed in the first
area.
3. The transmission of claim 1 wherein the second clutch is disposed
within the third area.
4. The transmission of claim 1 wherein the second clutch is disposed
within the fourth area.
5. The transmission of claim 1 wherein the fifth clutch is disposed
within the third area.
6. The transmission of claim 1 wherein the fifth clutch is disposed
within the fourth area.
7. The transmission of claim 1 wherein the fifth clutch is disposed
within the fifth area.
8. The transmission of claim 1 wherein the brake is disposed within
the first area.

9. The transmission of claim 1 wherein the first planetary gear set has
a first plurality of pinions and a second plurality of pinions rotatably supported by
the planet carrier member wherein the first plurality of pinions intermeshes with
the sun gear member and the second plurality of pinions intermeshes with the
ring gear member.

A transmission is disclosed having an input member, an output member, three planetary gear sets, a plurality of coupling members and a plurality of torque transmitting devices. Each of the planetary gear sets includes a sun gear
member, a planet carrier member, and a ring gear member. The torque transmitting devices include five clutches and one brake arranged within a
transmission housing.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=VRHkmmkHlgNT4ivjManfVw==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 269280
Indian Patent Application Number 1658/KOL/2008
PG Journal Number 42/2015
Publication Date 16-Oct-2015
Grant Date 13-Oct-2015
Date of Filing 25-Sep-2008
Name of Patentee GM GLOBAL TECHNOLOGY OPERATIONS, INC.
Applicant Address 300 RENAISSANCE CENTER, DETROIT, MICHIGAN
Inventors:
# Inventor's Name Inventor's Address
1 JAMES M. HART 16011 HAGGERTY, BELLEVILLE, MICHIGAN 48111
2 SCOTT H. WITTKOPP 6189 OAKHURST DRIVE, YPSILANTI, MICHIGAN 48197
3 ANDREW W. PHILLIPS 1052 CUTLER CIRCLE SALINE, MICHIGAN 48176
4 CLINTON E. CAREY 215 RIVERVIEW AVENUE MONROE, MICHIGAN 48162
PCT International Classification Number F16H3/44; F16H3/44
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/984550 2007-11-01 U.S.A.